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Suppose that you have an abstract for a scientific paper: we study surface and bulk properties of porous films produced by a model in which particles incide perpendicularly to a substrate , interact with deposited neighbors in its trajectory , and aggregate laterally with probability of order @xmath0 at each position . the model generalizes ballistic - like models by allowing attachment to particles below the outer surface . for small values of @xmath0 , a crossover from uncorrelated deposition ( ud ) to correlated growth is observed . simulations are performed in @xmath1 and @xmath2 dimensions . extrapolation of effective exponents and comparison of roughness distributions confirm kardar - parisi - zhang roughening of the outer surface for @xmath3 . a scaling approach for small @xmath0 predicts crossover times as @xmath4 and local height fluctuations as @xmath5 at the crossover , independently of substrate dimension . these relations are different from all previously studied models with crossovers from ud to correlated growth due to subsurface aggregation , which reduces scaling exponents . the same approach predicts the porosity and average pore height scaling as @xmath6 and @xmath5 , respectively , in good agreement with simulation results in @xmath1 and @xmath2 dimensions . these results may be useful to modeling samples with desired porosity and long pores . . And you have already written the first three sentences of the full article: a widely studied model for growth of porous films is ballistic deposition ( bd ) @xcite , in which the particles incide perperdicularly to the substrate and aggregate at the first contact with the deposit @xcite . bd was originally proposed to describe sedimentary rock formation @xcite and was extended to model thin film growth and related systems by considering other aggregation mechanisms , non - colimated particle flux , or polydispersivity of particle size @xcite . most works on the ballistic - like models address the scaling features of the outer surface of the deposits , particularly for the connections with kardar - parisi - zhang ( kpz ) @xcite roughening .. Please generate the next two sentences of the article

some works also connect the surface growth dynamics and the bulk properties of the porous deposits @xcite . this is an essential step for proposing models of porous materials , which have a large variety of technological applications , frequently in the form of thin films @xcite .

Suppose that you have an abstract for a scientific paper: we briefly overview the new features of planetpack2 , the forthcoming update of planetpack , which is a software tool for exoplanets detection and characterization from doppler radial velocity data . among other things , this major update brings parallelized computing , new advanced models of the doppler noise , handling of the so - called keplerian periodogram , and routines for transits fitting and transit timing variation analysis . . And you have already written the first three sentences of the full article: planetpack is a software tool that facilitates the detection and characterization of exoplanets from the radial velocity ( rv ) data , as well as basic tasks of long - term dynamical simulations in exoplanetary systems . the detailed description of the numeric algorithms implemented in planetpack is given in the paper @xcite , coming with its initial 1.0 release . after that several updates of the package were released , offering a lot of bug fixes , minor improvements , as well as moderate expansions of the functionality . as of this writing , the current downloadable version of planetpack is 1.8.1 . the current source code , as well as the technical manual , can be downloaded at ` http://sourceforge.net/projects/planetpack ` . here. Please generate the next two sentences of the article

we pre - announce the first major update of the package , planetpack 2.0 , which should be released in the near future . in addition to numerous bug fixes , this update includes a reorganization of the large parts of its architecture , and several new major algorithms .

Suppose that you have an abstract for a scientific paper: decoherence time has been calculated for an optical ion trap of be atoms in a bistable potential model . comparison has been made between decoherence time and zeno time for double well potential as a special case . zeno time is considered as a lower limit of decoherence time for sustainable quantum coherence . equality of the respective timescales provides a certain transitional temperature , below which decoherence can be asymptotically minimized . * pacs numbers : * 03.65.xp , 03.65.yz + * keywords : * dissipative quantum system , decoherence , zeno time . . And you have already written the first three sentences of the full article: quantum memory can store information in superposition states of a collection of two - level systems . optical ion trap by laser cooling has been prepared to construct quantum logic gates @xcite . in those systems , negative role played by quantum decoherence @xcite is quite significant . randomization of the quantum states produced by entanglement with environmental modes is inevitable in case of storage or processing of non - orthogonal states and environmental interaction allows leakage of some information to the environment @xcite . since it is practically impossible to disentangle the system from the environment , our main efforts are focussed on minimizing decoherence . in this attempt of decoherence minimization. Please generate the next two sentences of the article

, zeno dynamics plays a very significant role @xcite . quantum zeno effect @xcite is depicted as the complete freezing of the decay dynamics due to frequent measurement .

Suppose that you have an abstract for a scientific paper: gene set enrichment analysis ( gsea ) and its variations aim to discover collections of genes that show moderate but coordinated differences in expression . however , such techniques may be ineffective if many individual genes in a phenotype - related gene set have weak discriminative power . a potential solution is to search for combinations of genes that are highly differentiating even when individual genes are not . although such techniques have been developed , these approaches have not been used with gsea to any significant degree because of the large number of potential gene combinations and the heterogeneity of measures that assess the differentiation provided by gene groups of different sizes . to integrate the search for differentiating gene combinations and gsea , we propose a general framework with two key components : ( a ) a procedure that reduces the number of scores to be handled by gsea to the number of genes by summarizing the scores of the gene combinations involving a particular gene in a single score , and ( b ) a procedure to integrate the heterogeneous scores from combinations of different sizes and from different gene combination measures by mapping the scores to p - values . experiments on four gene expression data sets demonstrate that the integration of gsea and gene combination search can enhance the power of traditional gsea by discovering gene sets that include genes with weak individual differentiation but strong joint discriminative power . also , gene sets discovered by the integrative framework share several common biological processes and improve the consistency of the results among three lung cancer data sets . . And you have already written the first three sentences of the full article: microarray technology is an important tool to monitor gene - expression in bio - medical studies @xcite . a common experimental design is to compare two sets of samples with different phenotypes , e.g. diseased and normal tissue , with the goal of discovering differentially expressed genes @xcite . statistical testing procedures , such as such as the t - test and significance analysis of microarrays @xcite , have been extensively studied and widely used .. Please generate the next two sentences of the article

subsequently , multiple testing corrections are usually applied @xcite . a comprehensive review of such approaches are presented in @xcite .

Suppose that you have an abstract for a scientific paper: we present scaling relations between stellar - mass ( @xmath0 ) and the size of galaxies at @xmath1 for half- ( @xmath2 ) and 90 percent - light ( @xmath3 ) radii , using a deep @xmath4-band selected catalogue taken with the subaru telescope and moircs in the goods - north region . the logarithmic slope @xmath5 is independent of redshift in a wide mass range of @xmath6 m@xmath7 , irrespective of galaxy populations ( star - forming , quiescent ) . the offset change is @xmath8 percent . provided that optical light in the rest frame traces the stellar mass of galaxies , the universal relation demonstrates that the stellar mass was built up in galaxies over their cosmic histories in a similar manner on average irrelevant to galaxy mass . the small offset in each stellar mass bin from the universal relation shows weak size evolution at a given mass . there is a moderate increase of 3050 percent for @xmath2 and @xmath3 for less massive galaxies ( @xmath9 m@xmath7 ) from @xmath10 to @xmath11 , while the sizes remains unchanged or slightly decrease towards @xmath12 . for massive galaxies ( @xmath13 m@xmath7 ) , the evolution is @xmath14 % increase in @xmath3 from @xmath10 to @xmath12 , though that in @xmath2 is weaker . the evolution of compactness factor , @xmath15 , which becomes smaller at lower redshift , is suggestive of minor merging effect in the outer envelope of massive galaxies . [ firstpage ] galaxies : evolution galaxies : fundamental parameters galaxies : high - redshift infrared : galaxies . . And you have already written the first three sentences of the full article: the scale size of galaxies is one of the fundamental parameters to elucidate the history of galaxy formation and evolution . the change of size and stellar - mass relations over cosmic time would pose strong constraints on models of galaxy evolution . the observational relations between galaxy size and stellar mass have been studied in the local universe , based on the sloan digital sky survey ( shen et al .. Please generate the next two sentences of the article

2003 ; bernardi et al . 2011 ) . using rest - frame optical bands , which presumably trace the distribution of stellar mass in galaxies , many studies have investigated galaxy sizes at higher redshift as a function of stellar mass for massive galaxies ( @xmath16 m@xmath7 ) . for example ,

Suppose that you have an abstract for a scientific paper: we study the relaxation dynamics of systems of straight , parallel crystal dislocations , starting from initially random and uncorrelated positions of the individual dislocations . a scaling model of the relaxation process is constructed by considering the gradual extinction of the initial density fluctuations present in the system . the model is validated by ensemble simulations of the discrete dynamics of dislocations . convincing agreement is found for systems of edge dislocations in single slip irrespective of the net burgers vector of the dislocation system . it is also demonstrated that the model does not work in multiple slip geometries . _ keywords _ : defects ( theory ) , fluctuations ( theory ) , plasticity ( theory ) . And you have already written the first three sentences of the full article: the creation and motion of large numbers of crystal lattice dislocations is the most fundamental feature of crystal plasticity . during the last half century , the physical properties of individual dislocations and their interactions with localised obstacles have been studied extensively . on the other hand , the complex collective dynamics of strongly interacting many - dislocation systems is still far from being understood . fortunately , everyday plastic deformation processes very often proceed orders of magnitude slower than the typical relaxation times of the underlying dislocation system . these conditions often permit to study the problem in a quasistatic approximation @xcite . beyond the quasistatic limit , however , much less work has been devoted to studying the dynamics of collective dislocation motions which lead to the formation of metastable configurations , and to transitions between such configurations in driven dislocation systems .. Please generate the next two sentences of the article

however , such collective motions are crucial for understanding rapid dislocation processes which not only occur in shock loading but , in the form of dislocation avalanches , are a generic feature of the dynamics of driven dislocation systems @xcite . the first studies of dynamic relaxation processes in dislocation systems were performed by miguel et al . with the protocol of applying a constant external shear stress to well relaxed dislocation configurations @xcite .

Suppose that you have an abstract for a scientific paper: a theoretical model for the calculation of the phonon - drag thermopower , @xmath0 , in degenerately doped semiconducting single - wall carbon nanotubes ( swcnts ) is proposed . detailed calculations of @xmath0 are performed as a function of temperature , tube radius and position of the fermi level . we derive a simple analytical expression for @xmath0 that can be utilized to determine the free carrier density in doped nanotubes . at low temperatures @xmath0 shows an activated behavior characteristic of the one - dimensional ( 1d ) character of carriers . screening effects are taken into account and it is found that they dramatically reduce the magnitude of @xmath0 . our results are compared with previous published experimental data in bulk p - doped swcnt materials . excellent agreement is obtained in the temperature range 10 - 200 k for a consistent set of parameters . this is a striking result in view of the complexity of these systems . . And you have already written the first three sentences of the full article: thermopower , @xmath1 , is an important transport coefficient that offers valuable information about the electronic structure , the scattering processes and the mechanisms of carrier - phonon coupling in a system . in the last few years there has been growing experimental interest in @xmath1 of single wall carbon nanotubes ( swcnts ) . several groups have reported thermopower measurements on bulk swcnt materials ( e.g. , mats , fibers , films ) @xcite and on individual swcnts @xcite .. Please generate the next two sentences of the article

however , only modest progress has been made up to now in understanding the unique features of @xmath1 in these systems . interesting issues concerning the large positive thermopower ( @xmath2 80 @xmath3v / k ) in pristine samples @xcite , the change of sign of @xmath1 upon exposure to oxygen @xcite and the effect of carrier - phonon coupling @xcite on @xmath1 still remain open .

Suppose that you have an abstract for a scientific paper: relationships between the x - ray and radio behavior of black hole x - ray binaries during outbursts have established a fundamental coupling between the accretion disks and radio jets in these systems . i begin by reviewing the prevailing paradigm for this disk - jet coupling , also highlighting what we know about similarities and differences with neutron star and white dwarf binaries . until recently , this paradigm had not been directly tested with dedicated high - angular resolution radio imaging over entire outbursts . moreover , such high - resolution monitoring campaigns had not previously targetted outbursts in which the compact object was either a neutron star or a white dwarf . to address this issue , we have embarked on the jet acceleration and collimation probe of transient x - ray binaries ( jacpot xrb ) project , which aims to use high angular resolution observations to compare disk - jet coupling across the stellar mass scale , with the goal of probing the importance of the depth of the gravitational potential well , the stellar surface and the stellar magnetic field , on jet formation . our team has recently concluded its first monitoring series , including ( e)vla , vlba , x - ray , optical , and near - infrared observations of entire outbursts of the black hole candidate h1743 - 322 , the neutron star system aquila x-1 , and the white dwarf system ss cyg . here i present preliminary results from this work , largely confirming the current paradigm , but highlighting some intriguing new behavior , and suggesting a possible difference in the jet formation process between neutron star and black hole systems . . And you have already written the first three sentences of the full article: jets are found in accreting systems throughout the visible universe . for stellar - mass accretors , the evolution of such jets occurs on human timescales , and can be probed by resolved monitoring observations . x - ray binaries are one such class of objects , in which two distinct types of jets are observed , with a clear connection between the x - ray state of the source and the observed radio emission . from the flat radio spectra seen in the hard x - ray state , the presence of steady , compact , partially self - absorbed outflows. Please generate the next two sentences of the article

is inferred , which have been directly resolved in two black hole ( bh ) systems ( ( * ? ? ? * dhawan et al .

Suppose that you have an abstract for a scientific paper: we present a x - ray survey of the disrupted recycled pulsars ( drps ) , isolated radio pulsars with @xmath0 ms and @xmath1 g. these observations were motivated as a search for the immediate descendants of the @xmath2 central compact objects ( ccos ) in supernova remnants , three of which have similar timing and magnetic properties as the drps , but are bright , thermal x - ray sources consistent with minimal neutron star cooling curves . since none of the dprs were detected , there is no evidence that they are `` orphaned '' ccos , neutron stars whose supernova remnants has dissipated . upper limits on their thermal x - ray luminosities are in the range log @xmath3=31.8 - 32.8 $ ] , which implies cooling ages @xmath4 yr , roughly 10 times the ages of the @xmath5 known ccos in a similar volume of the galaxy . the order of a hundred cco descendants that could be detected by this method are thus either intrinsically radio quiet , or occupy a different region of ( @xmath6 ) parameter space from the drps . this motivates a new x - ray search for orphaned ccos among radio pulsars with larger @xmath7-fields , which could verify the theory that their fields are buried by fall - back of supernova ejecta , but quickly regrow to join the normal pulsar population . . And you have already written the first three sentences of the full article: the group of about @xmath8 so - called central compact objects ( ccos ) in supernova remnants ( snrs ) are distinguished by their steady surface thermal x - ray flux , lack of surrounding pulsar wind nebula , and non - detection at any other wavelength @xcite . three ccos are known pulsars , with periods in the range @xmath9 s , and spin - down rates that provide an estimate of their surface dipole magnetic field strength , which falls in the range @xmath10 g @xcite , smaller than that of any other young neutron star ( ns ) . this weak magnetic field is evidently the physical basis of the cco class .. Please generate the next two sentences of the article

the homogeneous properties of the approximately seven remaining ccos that have not yet been seen to pulse suggest that they have similar or even weaker @xmath7-fields than the known cco pulsars , and a more uniform surface temperature . that ccos are found in snrs ( of ages @xmath11 yr ) in comparable numbers to other classes of nss implies that they must represent a significant fraction of ns births , probably greater than that of magnetars , for example , as only 45 galactic snrs are known to host magnetars @xcite .

Suppose that you have an abstract for a scientific paper: strongly interacting fermi gases provide a clean and controllable laboratory system for modeling strong interparticle interactions between fermions in nature , from high temperature superconductors to neutron matter and quark - gluon plasmas . model - independent thermodynamic measurements , which do not require theoretical models for calibrations , are very important for exploring this important system experimentally , as they enable direct tests of predictions based on the best current non - perturbative many - body theories . at duke university , we use all - optical methods to produce a strongly interacting fermi gas of spin-1/2-up and spin-1/2-down @xmath0li atoms that is magnetically tuned near a collisional ( feshbach ) resonance . we conduct a series of measurements on the thermodynamic properties of this unique quantum gas , including the energy @xmath1 , entropy @xmath2 , and sound velocity @xmath3 . our model - independent measurements of @xmath1 and @xmath2 enable a precision study of the finite temperature thermodynamics . the @xmath4 data are directly compared to several recent predictions . the temperature in both the superfluid and normal fluid regime is obtained from the fundamental thermodynamic relation @xmath5 by parameterizing the @xmath4 data using two different power laws that are joined with continuous @xmath1 and @xmath6 at a certain entropy @xmath7 , where the fit is optimized . we observe a significant change in the scaling of @xmath1 with @xmath2 above and below @xmath7 . taking the fitted value of @xmath7 as an estimate of the critical entropy for a superfluid - normal fluid phase transition in the strongly interacting fermi gas , we estimate the critical parameters . our @xmath4 data are also used to experimentally calibrate the endpoint temperatures obtained for adiabatic sweeps of the magnetic field between the ideal and strongly interacting regimes . this enables the first experimental calibration of the temperature scale used in experiments on fermionic.... And you have already written the first three sentences of the full article: interacting fermionic particles play a central role in the structure of matter and exist over a very broad range of energies , from extremely low temperature trapped atomic fermi gases , where @xmath10 k @xcite , to very high temperature primordial matter , like quark - gluon plasmas , where @xmath11 k @xcite . for all of these systems , the most intriguing physics is related to very strong interactions between fermionic particles , such as the strong coupling between electrons in high-@xmath8 superconductors and the strong interactions between neutrons in neutron matter . current many - body quantum theories face great challenges in solving problems for strongly interacting fermi systems , due to the lack of a small coupling parameter . for example , the critical temperature of a superfluid - normal fluid transition in a strongly interacting fermi gas has been controversial for many years .. Please generate the next two sentences of the article

the critical temperature @xmath12 has been predicted to have values in the range between 0.15 and 0.35 by different theoretical methods @xcite . a complete understanding of the physics of strongly interacting systems can not yet be obtained from a theoretical point of view .

Suppose that you have an abstract for a scientific paper: i review the constraints imposed by the observed extragalactic background light ( ebl ) on the history of the stellar birthrate in galaxies . at faint magnitudes , the logarithmic slope of the galaxy counts is flatter than @xmath0 in all seven @xmath1 optical bandpasses of the _ hubble deep field - south _ imaging survey . the integration of the number counts provides a lower limit to the surface brightness of the optical extragalactic sky of @xmath2 , comparable to the intensity of the far - ir background from _ cobe _ data . if the initial mass function has a salpeter slope with a lower mass cutoff consistent with observations of m subdwarf disk stars , a lower limit of @xmath3 ( at hubble constant @xmath4 ) is derived for the visible ( processed gas @xmath5 stars ) mass density needed to generate an extragalactic background light ( ebl ) at a level of @xmath6 . the current ` best - guess ' estimate to @xmath7 is @xmath8 , about 16% of the nucleosynthetic baryon density . the contribution of quasar activity to the observed ebl is unlikely to exceed 20% . . And you have already written the first three sentences of the full article: recent progress in our understanding of faint galaxy data made possible by the combination of _ hubble space telescope _ ( _ hst _ ) deep imaging and ground - based spectroscopy has dramatically increased our knowledge of the evolution of the stellar birthrate in optically - selected galaxies from the present - epoch up to @xmath9 @xcite , @xcite , @xcite . the explosion in the quantity of information available on the high - redshift universe at optical wavelengths has been complemented by the measurement of the far - ir / sub - mm background by dirbe and firas onboard the _ cobe _ satellite @xcite , @xcite , @xcite , by the detection of distant ultraluminous sub - mm sources with the scuba camera @xcite , @xcite , and by theoretical progress made in understanding how intergalactic gas follows the dynamics dictated by dark matter halos until radiative , hydrodynamic , and star formation processes take over @xcite , @xcite , @xcite .. Please generate the next two sentences of the article

the ir data have revealed the ` optically - hidden ' side of galaxy formation , and shown that a significant fraction of the energy released by stellar nucleosynthesis is re - emitted as thermal radiation by dust @xcite , @xcite . the underlying goal of all these efforts is to understand the growth of cosmic structures , the internal properties of galaxies and their evolution , and ultimately to map the star formation history of the universe from the end of the cosmic ` dark age ' to the present epoch . in this talk

Suppose that you have an abstract for a scientific paper: we present a generalization of the multiphase chemical evolution model applied to a wide set of theoretical galaxies with different masses and evolutionary rates . this generalized set of models has been computed using the so - called _ universal rotation curve _ from @xcite to calculate the radial mass distribution of 44 _ theoretical _ protogalaxies . this distribution is a fundamental input which , besides its own effect on the galaxy evolution , defines the characteristic collapse time - scale or gas infall rate onto the disc . we have adopted 10 sets of values , between 0 and 1 , for the molecular cloud and star formation efficiencies , as corresponding to their probability nature , for each one of the radial distributions of total mass . thus , we have constructed a bi - parametric grid of models , depending on those efficiency sets and on the rotation velocity , whose results are valid in principle for any spiral or irregular galaxy . the model results provide the time evolution of different regions of the disc and the halo along galactocentric distance , measured by the gas ( atomic and molecular ) and stellar masses , the star formation rate and chemical abundances of 14 elements , for a total of 440 models . this grid may be used to estimate the evolution of a given galaxy for which only present time information such as radial distributions of elemental abundances , gas densities and/or star formation , which are the usual observational constraints of chemical evolution models is available . [ firstpage ] galaxies : abundances galaxies : evolution galaxies : spirals galaxies : stellar content . And you have already written the first three sentences of the full article: chemical evolution models ( cem ) @xcite were early developed to try to understand the origin of the radial gradients of abundances , observed in our galaxy ( mwg ) . most numerical models in the literature , including the multiphase model used in this work , explain the existence of this radial gradient by the combined effects of a star formation rate ( sfr ) and an infall of gas which vary with galactocentric radius in the galaxy . a radial decrease of abundances has also been observed in most spiral galaxies @xcite although the shape of the radial distribution changes from galaxy to galaxy . among other global trends. Please generate the next two sentences of the article

it is found that for isolated non - barred spirals the steepness of the radial gradient depends on morphological type , with later types showing steeper gradients @xcite , with other general galaxy properties as surface brightness and neutral and molecular gas fractions also playing a role @xcite . the radial gradient tends to be wiped out however for strongly barred galaxies which show flat abundance distributions @xcite .

Suppose that you have an abstract for a scientific paper: for short , high - intensity electron bunches , alkali - tellurides have proved to be a reliable photo - cathode material . measurements of lifetimes in an rf gun of the clic test facility ii at field strengths greater than 100 mv / m are presented . before and after using them in this gun , the spectral response of the cs - te and rb - te cathodes were determined with the help of an optical parametric oscillator . the behaviour of both materials can be described by spicer s 3-step model . whereas during the use the threshold for photo - emission in cs - te was shifted to higher photon energies , that of rb - te did not change . our latest investigations on the stoichiometric ratio of the components are shown . the preparation of the photo - cathodes was monitored with 320 nm wavelength light , with the aim of improving the measurement sensitivity . the latest results on the protection of cs - te cathode surfaces with csbr against pollution are summarized . new investigations on high mean current production are presented . . And you have already written the first three sentences of the full article: in the ctf ii drive beam gun , cs - te photocathodes are used to produce a pulse train of 48 electron bunches , each 10ps long and with a charge of up to 10nc @xcite . in ctf , the main limit to lifetime is the available laser power , which requires a minimal quantum efficiency ( qe ) of 1.5% to produce the nominal charge . although cs - te photocathodes are widely used , a complete understanding , especially of their aging process , is still lacking . spectra of the qe against exciting photons may help to understand the phenomenon .. Please generate the next two sentences of the article

according to spicer @xcite , the spectra of the quantum efficiency ( qe ) of semiconductors with respect to the energy of the exciting photons ( @xmath0 ) can be described as : @xmath1 where @xmath2 is the threshold energy for photoemission , c@xmath3 and c@xmath4 are constants . to measure the spectral response of photocathodes , wavelengths from the near uv throughout the visible are necessary . to attain these , an * o*ptical * p*arametrical * o*scillator was built @xcite . a frequency - tripled nd : yag laser pumps a betabarium borate ( bbo ) crystal in a double - pass configuration , as shown in fig.[fig : opo ] .

Suppose that you have an abstract for a scientific paper: we present an inelastic neutron scattering study on single - crystalline lifeas devoted to the characterization of the incommensurate antiferromagnetic fluctuations at @xmath0 . time - of - flight measurements show the presence of these magnetic fluctuations up to an energy transfer of 60 mev , while polarized neutrons in combination with longitudinal polarization analysis on a triple - axis spectrometer prove the pure magnetic origin of this signal . the normalization of the magnetic scattering to an absolute scale yields that magnetic fluctuations in lifeas are by a factor eight weaker than the resonance signal in nearly optimally co - doped bafe@xmath1as@xmath1 , although a factor two is recovered due to the split peaks owing to the incommensurability . the longitudinal polarization analysis indicates weak spin space anisotropy with slightly stronger out - of - plane component between 6 and 12 mev . furthermore , our data suggest a fine structure of the magnetic signal most likely arising from superposing nesting vectors . . And you have already written the first three sentences of the full article: the interest in the feas - based superconductors@xcite is ongoing after six years of extensive research as still no consensus has been achieved concerning the superconducting character and pairing mechanism . lifeas is special amongst the many feas - based superconductors , as superconductivity appears in the parent compound at elevated temperatures without doping or application of pressure . this particularity of lifeas most likely arises from its electronic structure with strongly reduced nesting between electron and hole fermi - surface sheets as it was first deduced from angle - resolved photoemission spectroscopy ( arpes ) @xcite . in the 1111 and 122 families. Please generate the next two sentences of the article

( named after their stoichiometry ) the fermi nesting conditions are excellent stabilizing a spin density wave ( sdw ) , which has to be suppressed by doping@xcite or the application of pressure@xcite in order to reach the superconducting state . lifeas does not exhibit any structural transition nor a magnetically ordered phase.@xcite theoretical calculations@xcite explain this fact by its poor fermi nesting properties and unusually shallow hole pockets around the @xmath2 point , which is in agreement with arpes experiments.@xcite the flat top of the hole pockets implies a large density of states around the @xmath2 point and in combination with small - momentum scattering vectors within the inner hole pocket this would favor ferromagnetic fluctuations and a triplet pairing mechanism.@xcite the symmetry of the order parameter has been a controversial subject , several reports using arpes , quasiparticle interference ( qpi ) or theoretical approaches favor an @xmath3 wave,@xcite while there is also support for a @xmath4-wave state.@xcite although the calculations in ref .

Suppose that you have an abstract for a scientific paper: by means of one - step model calculations the strong in - plane anisotropy seen in angle - resolved photoemission of the well - known iron pnictide prototype compounds and in their low - temperature antiferromagnetic phases is investigated . the fully - relativistic calculations are based on the korringa - kohn - rostoker - green function approach combined with the coherent potential approximation alloy theory to account for the disorder induced by co substitution on fe sites in a reliable way . the results of the calculations can be compared directly to experimental spectra of detwinned single crystals . one finds very good agreement with experiment and can reveal all features of the electronic structure contributing to the in - plane anisotropy . in particular the local density approximation can capture most of the correlation effects for the investigated system without the need for more advanced techniques . in addition , the evolution of the anisotropy for increasing co concentration @xmath0 in can be tracked almost continuously . the results are also used to discuss surface effects and it is possible to identify clear signatures to conclude about different types of surface termination . . And you have already written the first three sentences of the full article: nowadays the family of iron pnictides is a well - established and important prototype system for unconventional high - temperature superconductivity . starting with the first famous compound @xcite in 2008 , today several different sub - families with a wide structural variety are known . all different groups of iron pnictides share some common physical properties , such as their interesting and sometimes puzzling magnetic behavior .. Please generate the next two sentences of the article

most compounds show a phase transition at low temperatures from a tetragonal to an orthorhombic crystal symmetry which is typically accompanied by the formation of long - range antiferromagnetic order.@xcite it is common believe that the suppression of these phase transitions for example by chemical substitution is crucial for the emergence of unconventional superconductivity.@xcite although it is obvious that an understanding of the magnetic fluctuations in the iron pnictides is mandatory to unveil the physics underlying the superconductivity , this task has proven to be more complex than anticipated.@xcite for example , there was discussion in the literature whether the magnetic moments are better described by an itinerant@xcite or a localized@xcite model and there is up to now no consensus concerning the role of correlation effects@xcite . furthermore , the magnitude of the magnetic moments is difficult to reproduce within density functional theory ( dft ) and it is known to be quite sensitive to computational parameters.@xcite one of the most important experimental tools to get insight into the electronic structure of the iron pnictides is angle - resolved photoemission spectroscopy ( arpes ) . there are numerous publications on this topic , although it was shown that dft calculations have typically problems to reproduce all features of the arpes spectra correctly.@xcite this is often ascribed to strong correlation effects , although this question is still under discussion.@xcite another important difficulty which so far is often ignored is the connection between the magnetic phase of the iron pnictides and the resulting consequences for arpes .

Suppose that you have an abstract for a scientific paper: we give an exposition of the parametrization method of @xcite in the context of the multisymplectic approach to field theory , as presented in @xcite . the purpose of the formalism developed herein is to make any classical field theory , containing a metric as a sole background field , generally covariant ( that is , _ parametrized _ , with the spacetime diffeomorphism group as a symmetry group ) as well as fully dynamic . this is accomplished by introducing certain `` covariance fields '' as genuine dynamic fields . as we shall see , the multimomenta conjugate to these new fields form the piola kirchhoff version of the stress - energy - momentum tensor field , and their euler lagrange equations are vacuously satisfied . thus , these fields have no additional physical content ; they serve only to provide an efficient means of parametrizing the theory . our results are illustrated with two examples , namely an electromagnetic field and a klein gordon vector field , both on a background spacetime . . And you have already written the first three sentences of the full article: when one is dealing with classical field theories on a spacetime , the metric may appear as a given background field or it may be a genuine dynamic field satisfying the einstein equations . the latter theories are often generally covariant , with the spacetime diffeomorphism group as symmetry group , but the former often are considered to have only the isometry group of the metric as a symmetry group . however , @xcite ( see also @xcite ) indicated how theories with a background metric can be parametrized , that is , considered as theories that are fully covariant , if one introduces the diffeomorphisms themselves as dynamic fields .. Please generate the next two sentences of the article

the goal of this paper is to develop this idea in the context of multisymplectic classical field theory and to make connections with stress - energy - momentum ( `` sem '' ) tensors . as we shall see , the multimomenta conjugate to these new covariance fields form , to borrow a phrase from elasticity theory , the piola

Suppose that you have an abstract for a scientific paper: flagellated bacteria exploiting helical propulsion are known to swim along circular trajectories near surfaces . fluid dynamics predicts this circular motion to be clockwise ( cw ) above a rigid surface ( when viewed from inside the fluid ) and counter - clockwise ( ccw ) below a free surface . recent experimental investigations showed that complex physicochemical processes at the nearby surface could lead to a change in the direction of rotation , both at solid surfaces absorbing slip - inducing polymers and interfaces covered with surfactants . motivated by these results , we use a far - field hydrodynamic model to predict the kinematics of swimming near three types of interfaces : clean fluid - fluid interface , slipping rigid wall , and a fluid interface covered by incompressible surfactants . representing the helical swimmer by a superposition of hydrodynamic singularities , we first show that in all cases the surfaces reorient the swimmer parallel to the surface and attract it , both of which are a consequence of the stokes dipole component of the swimmer flow field . we then show that circular motion is induced by a higher - order singularity , namely a rotlet dipole , and that its rotation direction ( cw vs. ccw ) is strongly affected by the boundary conditions at the interface and the bacteria shape . our results suggest thus that the hydrodynamics of complex interfaces provide a mechanism to selectively stir bacteria . . And you have already written the first three sentences of the full article: swimming microorganisms are ubiquitous in nature , and have long been known to play important roles in marine life ecosystems , animal reproduction , and infectious diseases . in these processes , cell motility is crucial.@xcite at the small scales relevant to swimming cells , inertial forces are negligible , and locomotion is constrained by purcell s `` scallop '' theorem stating that any body deformation reversible in time yields zero net motion.@xcite fluid - based cellular motility relies therefore on non - time reversible deformation , for instance by propagating waves along cilia or flagella.@xcite among the various types of locomotion seen in nature , one commonly observed for bacteria is that of helical propulsion , where a flagellum ( or a bundle of flagella ) rotates as a helix , inducing forward propulsion . a typical example of an organism employing helical propulsion is the bacterium _ escherichia coli _ coli_).@xcite this bacterium alternates `` run '' and `` tumble '' periods : in the former , flagella are synchronized in a coherent bundle and propel the cell forward , whereas in the latter flagella are disorganized , changing the cell orientation and subsequent swimming direction . during run periods , when _ e. coli _ cells are isolated in a bulk flow , they swim in straight ( noisy ) lines .. Please generate the next two sentences of the article

however , cell locomotion is strongly affected by nearby boundaries . swimming microorganisms often evolve in confined environments , be it by solid boundaries , free surfaces , or liquid interfaces . in some cases

Suppose that you have an abstract for a scientific paper: the decoding of low - density parity - check codes by the belief propagation ( bp ) algorithm is revisited . we check the iterative algorithm for its convergence to a codeword ( termination ) , we run monte carlo simulations to find the probability distribution function of the termination time , @xmath0 . tested on an example @xmath1 $ ] code , this termination curve shows a maximum and an extended algebraic tail at the highest values of @xmath0 . aiming to reduce the tail of the termination curve we consider a family of iterative algorithms modifying the standard bp by means of a simple relaxation . the relaxation parameter controls the convergence of the modified bp algorithm to a minimum of the bethe free energy . the improvement is experimentally demonstrated for additive - white - gaussian - noise channel in some range of the signal - to - noise ratios . we also discuss the trade - off between the relaxation parameter of the improved iterative scheme and the number of iterations . low - density parity - check ( ldpc ) codes @xcite are the best linear block error - correction codes known today @xcite . in addition to being good codes , i.e. capable of decoding without errors in the thermodynamic limit of an infinitely long block length , these codes can also be decoded efficiently . the main idea of belief propagation ( bp ) decoding is in approximating the actual graphical model , formulated for solving statistical inference maximum likelihood ( ml ) or maximum - a - posteriori ( map ) problems , by a tree - like structure without loops . being efficient but suboptimal the bp algorithm fails on certain configurations of the channel noise when close to optimal ( but inefficient ) map decoding would be successful . bp decoding allows a certain duality in interpretation . first of all , and following the so - called bethe - free energy variational approach @xcite , bp can be understood as a set of equations for beliefs ( bp - equations ) solving a constrained minimization problem.... And you have already written the first three sentences of the full article: consider a generic factor model @xcite with a binary configurational space , @xmath12 , @xmath13 , which is factorized so that the probability @xmath14 to find the system in the state @xmath15 and the partition function @xmath16 are @xmath17 where @xmath9 labels non - negative and finite factor - functions @xmath18 with @xmath19 and @xmath20 represents a subset of @xmath21 variables . relations between factor functions ( checks ) and elementary discrete variables ( bits ) , expressed as @xmath3 and @xmath4 , can be conveniently represented in terms of the system - specific factor ( tanner ) graph . if @xmath3 we say that the bit and the check are neighbors .. Please generate the next two sentences of the article

any spin ( a - posteriori log - likelihood ) correlation function can be calculated using the partition function , @xmath16 , defined by eq . ( [ p1 ] ) .

Suppose that you have an abstract for a scientific paper: the chemical fokker - planck equation and the corresponding chemical langevin equation are commonly used approximations of the chemical master equation . these equations are derived from an uncontrolled , second - order truncation of the kramers - moyal expansion of the chemical master equation and hence their accuracy remains to be clarified . we use the system - size expansion to show that chemical fokker - planck estimates of the mean concentrations and of the variance of the concentration fluctuations about the mean are accurate to order @xmath0 for reaction systems which do not obey detailed balance and at least accurate to order @xmath1 for systems obeying detailed balance , where @xmath2 is the characteristic size of the system . hence the chemical fokker - planck equation turns out to be more accurate than the linear - noise approximation of the chemical master equation ( the linear fokker - planck equation ) which leads to mean concentration estimates accurate to order @xmath3 and variance estimates accurate to order @xmath0 . this higher accuracy is particularly conspicuous for chemical systems realized in small volumes such as biochemical reactions inside cells . a formula is also obtained for the approximate size of the relative errors in the concentration and variance predictions of the chemical fokker - planck equation , where the relative error is defined as the difference between the predictions of the chemical fokker - planck equation and the master equation divided by the prediction of the master equation . for dimerization and enzyme - catalyzed reactions , the errors are typically less than few percent even when the steady - state is characterized by merely few tens of molecules . . And you have already written the first three sentences of the full article: chemical master equations ( cmes ) are the accepted mathematical description of chemical systems in well - mixed conditions @xcite . these equations provide a mesoscopic description of chemical kinetics , interpolating between the microscopic regime of molecular dynamics and the macroscopic regime of rate equations ( res ) . it has been shown that cmes are exact descriptions for any well - stirred and thermally equilibrated gas - phase chemical system @xcite .. Please generate the next two sentences of the article

more recently it has been rigorously confirmed that their validity extends to chemical reactions in well - stirred dilute solutions @xcite . however , well before these rigorous demonstrations of the microscopic physical basis of the cme , scientists have employed these equations to probe the nature of mesoscopic chemical kinetics and in particular to understand how this may differ from kinetics on macroscopic length scales ( see mcquarrie for a review @xcite of the literature up till 1967 ) .

Suppose that you have an abstract for a scientific paper: inspired by recent experiments where electron transport was measured across graphene nanoribbons ( gnr ) suspended between a metal surface and the tip of a scanning tunneling microscope [ koch _ et al_. , nat . nanotechnol . * 7 * , 713 ( 2012 ) ] , we present detailed first - principles simulations of inelastic electron tunneling spectroscopy ( iets ) of long pristine and defected armchair and zigzag nanoribbons under a range of charge carrier conditions . for the armchair ribbons we find two robust iets signals around 169 and 196 mv corresponding to the d- and g - modes of raman spectroscopy as well as additional fingerprints due to various types of defects in the edge passivation . for the zigzag ribbons we show that the spin state strongly influences the spectrum and thus propose iets as an indirect proof of spin polarization . . And you have already written the first three sentences of the full article: graphene as the basis of a new generation of electronics@xcite has been the center of much attention in the last years , and devices based on nanostructured graphene have been put forward . the most generic form of nanostructured graphene is graphene nanoribbons ( gnr),@xcite and other structures , such as graphene anti - dot lattices@xcite , can be viewed as networks of them . gnrs are potential candidates for molecular wires with tailored conductance properties . for graphene - based nanostructures. Please generate the next two sentences of the article

the edges and their passivation , as well as defects inside the structure , can play crucial roles for the transport properties.@xcite however , characterization of edge passivation or structural / chemical defects is challenging especially after device fabrication . raman spectroscopy@xcite can give information about defects on large areas of the sample , while tip - enhanced raman spectroscopy ( ters)@xcite have been used in combination with stm on gnrs .

Suppose that you have an abstract for a scientific paper: the situation that a scalar field provides the source of the accelerated expansion of the universe while rolling down its potential is common in both the simple models of the primordial inflation and the quintessence - based dark energy models . motivated by this point , we address the possibility of causing the current acceleration via the primordial inflation using a simple model based on hybrid inflation . we trigger the onset of the motion of the quintessence field via the waterfall field , and find that the fate of the universe depends on the true vacuum energy determined by choosing the parameters . we also briefly discuss the variation of the equation of state and the possible implementation of our scenario in supersymmetric theories . kaist - th/2005 - 16 1.5 cm 0.5 cm 1.2 cm . And you have already written the first three sentences of the full article: the discovery of the acceleration of the universe by the measurements of the luminosity - redshift relation for type ia supervonae @xcite , combined with the observations of the anisotropies in the cosmic microwave background ( cmb ) @xcite , confirmed that about 70% of the density of the universe is made up of an unknown form of energy . this component , usually referred to as dark energy " , is unclumped and smoothly distributed , with an exotic property that it has negative pressure to cause the expansion of the universe to accelerate . the simplest candidate of dark energy is a non - vanishing , positive cosmological constant @xcite .. Please generate the next two sentences of the article

we have to , however , explain why it is non - zero but vanishingly small ( @xmath0 ) : possibly we can resort to some yet unknown fundamental symmetry which makes the cosmological constant vanishingly small but non - zero , or we might invoke an anthropic consideration that the observed small value of the cosmological constant allows life and that is why we observe it @xcite ) different vacua , and some of them may be suitable for some kind of intelligent observers like us . ] . an alternative form of dark energy is a slowly rolling scalar field , called quintessence , which has not yet relaxed at its ground state @xcite . for recent years , there have been considerable developments in the dynamics of the quintessence field . for example , in the context of so - called tracker solutions @xcite , the simplest case arises for a potential of the form @xmath1 , where @xmath2 is positive and @xmath3 is an adjustable constant . by choosing @xmath3 suitably ,

Suppose that you have an abstract for a scientific paper: it is now well accepted that the galaxies are distributed in filaments , sheets and clusters all of which form an interconnected network known as the cosmic web . it is a big challenge to quantify the shapes of the interconnected structural elements that form this network . tools like the minkowski functionals which use global properties , though well suited for an isolated object like a single sheet or filament , are not suited for an interconnected network of such objects . we consider the local dimension @xmath0 , defined through @xmath1 , where @xmath2 is the galaxy number count within a sphere of comoving radius @xmath3 centered on a particular galaxy , as a tool to locally quantify the shape in the neigbourhood of different galaxies along the cosmic web . we expect @xmath4 and @xmath5 for a galaxy located in a filament , sheet and cluster respectively . using lcdm n - body simulations we find that it is possible to determine @xmath0 through a power law fit to @xmath2 across the length - scales @xmath6 to @xmath7 for @xmath8 of the galaxies . we have visually identified the filaments and sheets corresponding to many of the galaxies with @xmath9 and @xmath6 respectively . in several other situations the structure responsible for the @xmath0 value could not be visually identified , either due to its being tenuous or due to other dominating structures in the vicinity . we also show that the global distribution of the @xmath0 values can be used to visualize and interpret how the different structural elements are woven into the cosmic web . methods : data analysis - galaxies : statistics - large - scale structure of universe . And you have already written the first three sentences of the full article: filaments are the most prominent features visible in the galaxy distribution . this finding dates back to a few papers in the seventies and eighties @xcite . subsequent work substantiates this ( e.g. @xcite , @xcite , @xcite , @xcite , @xcite , @xcite , @xcite , @xcite ) and shows the filaments to be statistically significant @xcite .. Please generate the next two sentences of the article

it is now well accepted that galaxies are distributed in an interconnected network of clusters , sheets and filaments encircling voids . this complicated pattern is often referred to as the cosmic web . despite this progress

Suppose that you have an abstract for a scientific paper: the m31 globular cluster x - ray binary xb158 ( a.k.a . bo 158 ) exhibits intensity dips on a 2.78 hr period in some observations , but not others . the short period suggests a low mass ratio , and an asymmetric , precessing disk due to additional tidal torques from the donor star since the disk crosses the 3:1 resonance . previous theoretical 3d smoothed particle hydrodynamical modeling suggested a super - orbital disk precession period 29@xmath01 times the orbital period , i.e. @xmath181@xmath03 hr . we conducted a swift monitoring campaign of 30 observations over @xmath11 month in order to search for evidence of such a super - orbital period . fitting the 0.310 kev swift xrt luminosity lightcurve with a sinusoid yielded a period of 5.65@xmath00.05 days , and a @xmath25@xmath3 improvement in @xmath4 over the best fit constant intensity model . a lomb - scargle periodogram revealed that periods 5.45.8 days were detected at a @xmath23@xmath3 level , with a peak at 5.6 days . we consider this strong evidence for a 5.65 day super - orbital period , @xmath170% longer than the predicted period . the 0.310 kev luminosity varied by a factor @xmath15 , consistent with variations seen in long - term monitoring from chandra . we conclude that other x - ray binaries exhibiting similar long - term behaviour are likely to also be x - ray binaries with low mass ratios and super - orbital periods . . And you have already written the first three sentences of the full article: the m31 globular cluster ( gc ) b158 ( a.k.a . bo 158 ) , named following the revised bologna catalogue v3.4 @xcite , contains a bright x - ray source that was discovered by the einstein observatory @xcite , and has shown up in every x - ray observation of the region since ; we call this x - ray source xb158 . xb158 exhibited strong intensity modulation on a 10017@xmath050 s ( @xmath12.78 hr ) period during the 2002 january xmm - newton observation @xcite . @xcite found similar variation in the folded lightcurves from a 1991 june rosat observation and a 2000 june xmm - newton observation ; they found that the amplitude of modulation decreased with increasing source intensity .. Please generate the next two sentences of the article

they found no such modulation in the 2001 june xmm - newton observation , setting a 2@xmath3 upper limit of 10% modulation . assuming that this represents the orbital period , @xcite found that this is probably a neutron star binary with a low mass donor with a separation @xmath510@xmath6 cm ( i.e. a low mass xb - ray binary , lmxb ) .

Suppose that you have an abstract for a scientific paper: this paper introduces a projected principal component analysis ( projected - pca ) , which employs principal component analysis to the projected ( smoothed ) data matrix onto a given linear space spanned by covariates . when it applies to high - dimensional factor analysis , the projection removes noise components . we show that the unobserved latent factors can be more accurately estimated than the conventional pca if the projection is genuine , or more precisely , when the factor loading matrices are related to the projected linear space . when the dimensionality is large , the factors can be estimated accurately even when the sample size is finite . we propose a flexible semiparametric factor model , which decomposes the factor loading matrix into the component that can be explained by subject - specific covariates and the orthogonal residual component . the covariates effects on the factor loadings are further modeled by the additive model via sieve approximations . by using the newly proposed projected - pca , the rates of convergence of the smooth factor loading matrices are obtained , which are much faster than those of the conventional factor analysis . the convergence is achieved even when the sample size is finite and is particularly appealing in the high - dimension - low - sample - size situation . this leads us to developing nonparametric tests on whether observed covariates have explaining powers on the loadings and whether they fully explain the loadings . the proposed method is illustrated by both simulated data and the returns of the components of the s&p 500 index . ./style / arxiv - general.cfg , . And you have already written the first three sentences of the full article: factor analysis is one of the most useful tools for modeling common dependence among multivariate outputs . suppose that we observe data @xmath0 that can be decomposed as @xmath1 where @xmath2 are unobservable common factors ; @xmath3 are corresponding factor loadings for variable @xmath4 , and @xmath5 denotes the idiosyncratic component that can not be explained by the static common component . here , @xmath6 and @xmath7 , respectively , denote the dimension and sample size of the data . model ( [ eq1.1 ] ) has broad applications in the statistics literature .. Please generate the next two sentences of the article

for instance , @xmath8 can be expression profiles or blood oxygenation level dependent ( bold ) measurements for the @xmath9th microarray , proteomic or fmri - image , whereas @xmath4 represents a gene or protein or a voxel . see , for example , @xcite .

Suppose that you have an abstract for a scientific paper: device - to - device ( d2d ) communication has seen as a major technology to overcome the imminent wireless capacity crunch and to enable new application services . in this paper , we propose a social - aware approach for optimizing d2d communication by exploiting two layers : the social network and the physical wireless layers . first we formulate the physical layer d2d network according to users encounter histories . subsequently , we propose an approach , based on the so - called indian buffet process , so as to model the distribution of contents in users online social networks . given the social relations collected by the evolved node b ( enb ) , we jointly optimize the traffic offloading process in d2d communication . in addition , we give the chernoff bound and approximated cumulative distribution function ( cdf ) of the offloaded traffic . in the simulation , we proved the effectiveness of the bound and cdf . the numerical results based on real traces show that the proposed approach offload the traffic of enb s successfully . . And you have already written the first three sentences of the full article: the recent proliferation of smartphones and tablets has been seen as a key enabler for anywhere , anytime wireless communications . the rise of online services , such as facebook and youtube , significantly increases the frequency of users online activities . due to this continuously increasing demand for wireless access , a tremendous amount of data is circulating over today s wireless networks .. Please generate the next two sentences of the article

this increase in demand is straining current cellular systems , thus requiring novel approaches for network design . in order to cope with this wireless capacity crunch , device - to - device ( d2d ) communication underlaid on cellular systems , has recently emerged as a promising technique that can significantly boost the performance of wireless networks @xcite . in d2d communication , user equipments ( ues ) transmit data signals to each other over a direct link instead of through the wireless infrastructure , i.e. , the cellular network s evolved node bs ( enbs ) .

Suppose that you have an abstract for a scientific paper: several problems which could be thought of as belonging to recreational mathematics are described . they are all such that solutions to the problem depend on finding rational points on elliptic curves . many of the problems considered lead to the search for points of very large height on the curves , which ( as yet ) have not been found . . And you have already written the first three sentences of the full article: elliptic curves underpin some of the most advanced mathematics currently being pursued , most notably ( probably ) the proof of fermat s last theorem by sir andrew wiles . recreational number theory is enjoyed by many people with * no * professional mathematics qualifications . the purpose of the present survey is to show how , even a small knowledge of elliptic curves and a computer , can help solve many problems .. Please generate the next two sentences of the article

these problems are all reasonably simple to understand but can lead to some very interesting mathematics . we start with a simple * problem : * if possible , find rational numbers @xmath0 with @xmath1 where @xmath2 is a specified non - zero integer .

Suppose that you have an abstract for a scientific paper: we study the effect of an optical lattice ( ol ) on the ground - state properties of one - dimensional ultracold bosons with three - body attraction and two - body repulsion , which are described by a cubic - quintic gross - pitaevskii equation with a periodic potential . without the ol and with a vanishing two - body interaction term , soliton solutions of the townes type are possible only at a critical value of the three - body interaction strength , at which an infinite degeneracy of the ground - state occurs ; a repulsive two - body interaction makes such localized solutions unstable . we show that the ol opens a stability window around the critical point when the strength of the periodic potential is above a critical threshold . we also consider the effect of an external parabolic trap , studying how the stability of the solitons depends on matching between minima of the periodic potential and the minimum of the parabolic trap . . And you have already written the first three sentences of the full article: in the current studies of ultracold quantum gases , a great deal of interest has been drawn to the study of bose - einstein condensates ( becs ) loaded into optical lattices ( ols ) , i.e. , spatially periodic potentials induced by the interference between counterpropagating laser beams book1,book2,morsch06 . besides playing a crucial role in effectively tuning the interaction strength in the condensate , i.e. , the ratio between the kinetic and interaction energies @xcite , ols offer an extremely useful tool for studies of the transition between the superfluid and mott - insulator states @xcite , and for the investigation of effects in the matter - wave dynamics due to the interplay between nonlinearity and the quasi - discreteness , which is induced by a deep lattice potential @xcite . the mean - field dynamics of the bec loaded into the ol is described by the cubic gross - pitaevskii equation ( gpe ) with the periodic potential book1,book2,morsch06 .. Please generate the next two sentences of the article

the respective bogoliubov s excitation spectrum features a band structure , similar to electronic bloch bands in solid state . if the ol potential is deep enough , the lowest - band dynamics may be approximated by the discrete nonlinear schrdinger ( nls ) equation trombettoni01 . using this correspondence , the bec dynamics

Suppose that you have an abstract for a scientific paper: the resonance states of one- and two - particle hamiltonians are studied using variational expansions with real basis - set functions . the resonance energies , @xmath0 , and widths , @xmath1 , are calculated using the density of states and an @xmath2 golden rule - like formula . we present a recipe to select adequately some solutions of the variational problem . the set of approximate energies obtained shows a very regular behaviour with the basis - set size , @xmath3 . indeed , these particular variational eigenvalues show a quite simple scaling behaviour and convergence when @xmath4 . following the same prescription to choose particular solutions of the variational problem we obtain a set of approximate widths . using the scaling function that characterizes the behaviour of the approximate energies as a guide , it is possible to find a very good approximation to the actual value of the resonance width . . And you have already written the first three sentences of the full article: the methods used to calculate the energy and the lifetime of a resonance state are numerous @xcite and , in some cases , has been put forward over strong foundations @xcite . however , the analysis of the numerical results of a particular method when applied to a given problem is far from direct . the complex scaling ( complex dilatation ) method @xcite , when the hamiltonian @xmath5 allows its use , reveals a resonance state by the appearance of an isolated complex eigenvalue on the spectrum of the non - hermitian complex scaled hamiltonian , @xmath6 @xcite . of course in an actual implementation the rotation angle @xmath7 must be large enough to rotate the continuum part of the spectrum beyond the resonance s complex eigenvalue .. Please generate the next two sentences of the article

moreover , since most calculations are performed using finite variational expansions it is necessary to study the numerical data to decide which result is the most accurate . to worsen things the variational basis sets usually depend on one ( or more ) non - linear parameter . for bound states the non - linear parameter is chosen in order to obtain the lowest variational eigenvalue . for resonance states things

Suppose that you have an abstract for a scientific paper: we propose an automatic algorithm , named sdi , for the segmentation of skin lesions in dermoscopic images , articulated into three main steps : selection of the image roi , selection of the segmentation band , and segmentation . we present extensive experimental results achieved by the sdi algorithm on the lesion segmentation dataset made available for the isic 2017 challenge on skin lesion analysis towards melanoma detection , highlighting its advantages and disadvantages . . And you have already written the first three sentences of the full article: several diagnostic protocols are usually adopted by dermatologists for analyzing and classifying skin lesions , such as the so - called _ abcd - rule _ of dermoscopy @xcite . due to the subjective nature of examination , the accuracy of diagnosis is highly dependent upon human vision and dermatologist s expertise . computerized dermoscopic image analysis systems , based on a consistent extraction and analysis of image features , do not have the limitation of this subjectivity .. Please generate the next two sentences of the article

these systems involve the use of a computer as a second independent and objective diagnostic method , which can potentially be used for the pre - screening of patients performed by non - experienced operators . although computerized analysis techniques can not provide a definitive diagnosis , they can improve biopsy decision - making , which some observers feel is the most important use for dermoscopy @xcite .

Suppose that you have an abstract for a scientific paper: this paper describes postfix - gp system , postfix notation based genetic programming ( gp ) , for solving symbolic regression problems . it presents an object - oriented architecture of postfix - gp framework . it assists the user in understanding of the implementation details of various components of postfix - gp . postfix - gp provides graphical user interface which allows user to configure the experiment , to visualize evolved solutions , to analyze gp run , and to perform out - of - sample predictions . the use of postfix - gp is demonstrated by solving the benchmark symbolic regression problem . finally , features of postfix - gp framework are compared with that of other gp systems . + * _ keywords- _ * postfix genetic programming ; postfix - gp framework ; object oriented design ; gp software tool ; symbolic regression . And you have already written the first three sentences of the full article: evolutionary algorithms ( ea ) are a group of computational techniques , which employ the theory of natural selection to a population of individuals to generate better individuals . genetic programming ( gp ) is a paradigm of ea which uses hierarchical , tree structure , variable length representation to code solutions of a problem . gp can be used to intelligently search the solution space for finding the optimal solution of a problem .. Please generate the next two sentences of the article

there are many gp tools ( lil - gp , genexprotools , gplab , ecj , open beagle ) @xcite developed by gp practitioners . however , none of these address the following demands of end user before applying them to solve symbolic regression problems : ( i ) ease of use and ( ii ) small learning curve .

Suppose that you have an abstract for a scientific paper: in the framework of vector measures and the combinatorial approach to stochastic multiple integral introduced by rota and wallstrom [ _ ann . probab . _ * 25 * ( 1997 ) 12571283 ] , we present an it multiple integral and a stratonovich multiple integral with respect to a lvy process with finite moments up to a convenient order . in such a framework , the stratonovich multiple integral is an integral with respect to a product random measure whereas the it multiple integral corresponds to integrate with respect to a random measure that gives zero mass to the diagonal sets . a general hu meyer formula that gives the relationship between both integrals is proved . as particular cases , the classical hu meyer formulas for the brownian motion and for the poisson process are deduced . furthermore , a pathwise interpretation for the multiple integrals with respect to a subordinator is given . , and . . . And you have already written the first three sentences of the full article: let @xmath0 be a standard brownian motion . it @xcite defined the multiple stochastic integral of a function @xmath1 , @xmath2 taking care to ensure that the diagonal sets , like @xmath3 , do not contribute at all . for this reason the integral has very good properties and is easy to work with .. Please generate the next two sentences of the article

however , for a function of the form @xmath4 we have that , in general , @xmath5 that means the it multiple integral does not behave like the integral with respect to a product measure . many years later , hu and meyer @xcite introduced ( although they believed that this integral was already known @xcite , page 75 ) a multiple integral , @xmath6 , which followed the ordinary rules of multiple integration .

Suppose that you have an abstract for a scientific paper: when the cross section of @xmath0 production is considered varying with the energy of the nucleon - nucleon interaction the production of @xmath0 in pa and aa collisions has been studied using fritiof model . the calculation shows that the cross section of @xmath0 production per nucleon - nucleon collision " decreases with increasing mass number and centrality as a consequence of continuous energy loss of the projectile nucleons to the target nucleons in their successive binary nucleon - nucleon collisions . we have compared our model predictions with the experimental data of @xmath0 production . pacs number : 25.75.-q 3ex report - no : bthep - th-96 - 42 + dec . 1996 + tai an@xmath1 , chao wei qin@xmath2 and yao xiao xia@xmath3 ttttt = tt = a ) ccast ( world lab . ) , p. o. box 8730 beijing , p.r . china . + b ) institute of high energy physics , academia sinica , + p. o. box 918(4 - 1 ) , beijing , 100039 , p.r . china . + suppression of @xmath0 production in high energy heavy ion collisions was proposed as an effective signature of qgp formation ten years ago @xcite . the ensuing experimental data confirmed a significant suppression of @xmath0 production in both pa and aa collisions @xcite . however , alternative explanations of the @xmath0 suppression exist based on the absorption of @xmath0 in nuclear matter @xcite . the overall set of extensive data collected and analysed by na38 seems to support the absorption mechanism in p+b@xmath4 , o+b@xmath4 and s+u collisions . nevertheless a rather large absorption cross section ( @xmath5 6.2 mb ) has to be used in order to fit the experimental data , about three times larger than the total @xmath0-n cross section from the emc collaboration @xcite . such a difference was already noted long time ago in @xcite . recent calculations based on the colour octet model show that this phenomenological cross section could be understood by the absorption of pre - resonance states ( @xmath6 ) in nuclear matter @xcite . other.... And you have already written the first three sentences of the full article: we would like to thank d. jouan and zhang xiaofai for helpful discussions . this work is partly supported by the national natural science founction of china . 35 t. matsui and h. satz , phys .. Please generate the next two sentences of the article

b178 * , 416 ( 1986 ) . na38 collaboration , c. baglin et al .

Suppose that you have an abstract for a scientific paper: by using a tracking quintessence model we obtain that the position of the first doppler peak in the spectrum of cmb anisotropies only depends on the topology of the universe , @xmath0 , for any value of the ratio @xmath1 , so that such a dependence is perfectly valid in the range suggested by supernova observations . . And you have already written the first three sentences of the full article: recent experiments and observations have already opened up what one can actually call the era of precision cosmology . it is now hoped that next years will see rather impressive advances leading not just to the determination of key cosmological parameters with an accuracy not even dreamed five years ago , but also to unprecedented scrutinies on fundamental aspects of particle and field theories . in particular , the connection between recent boomerang ( de bernardis et al .. Please generate the next two sentences of the article

2000 ) and maxima ( hanany et al . 2000 ) experiments with theory is twofold . they are linked through predictions from either inflationary ( and perhaps cosmic string ) models by using fundamental particle physics arguments ( hu and white 1996 ) or from general more or less standard cosmological scenarios which may or may not include some new concepts such as quintessence ( cadwell , dave and steinhardt 1998 ) .

Suppose that you have an abstract for a scientific paper: a new cosmological model based on the de sitter gauge theory ( dsgt ) is studied in this paper . by some transformations , we find , in the dust universe , the cosmological equations of dsgt could form an autonomous system . we conduct dynamics analysis to this system , and find 9 critical points , among which there exist one positive attractor and one negative attractor . the positive attractor shows us that our universe will enter a exponential expansion phase in the end , which is similar to the conclusion of @xmath0cdm . we also carry out some numerical calculations , which confirms the conclusion of dynamics analysis . finally , we fit the model parameter and initial values to the union 2 snia dataset , present the confidence contour of parameters and obtain the best - fit values of parameters of dsgt . . And you have already written the first three sentences of the full article: at the end of the last century , the astronomical observations of high redshift type ia supernovae ( snia ) indicated that our universe is not only expanding , but also accelerating , which conflicts with our deepest intuition of gravity . with some other observations , such as cosmic microwave background radiation ( cmbr ) , baryon acoustic oscillations ( bao ) and large - scale structure ( lss ) , physicists proposed a new standard cosmology model , @xmath0cdm , which introduces the cosmological constant back again . although this unknown energy component accounts for 73% of the energy density of the universe , the measured value is too small to be explained by any current fundamental theories.@xcite-@xcite if one tries to solve this trouble phenomenologically by setting the cosmological constant to a particular value , the so - called fine - tuning problem would be brought up , which is considered as a basic problem almost any cosmological model would encounter . a good model should restrict the fine - tuning as much as possible . in order to alleviate this problem ,. Please generate the next two sentences of the article

various alternative theories have been proposed and developed these years , such as dynamical dark energy , modified gravity theories and even inhomogeneous universes . recently , a new attempt , called torsion cosmology , has attracted researchers attention , which introduces dynamical torsion to mimic the contribution of the cosmological constant .

Suppose that you have an abstract for a scientific paper: the tammes problem is to find the arrangement of @xmath0 points on a unit sphere which maximizes the minimum distance between any two points . this problem is presently solved for several values of @xmath0 , namely for @xmath1 by l. fejes tth ( 1943 ) ; for @xmath2 by schtte and van der waerden ( 1951 ) ; for @xmath3 by danzer ( 1963 ) and for @xmath4 by robinson ( 1961 ) . recently , we solved the tammes problem for @xmath5 . the optimal configuration of 14 points was conjectured more than 60 years ago . in the paper , we give a solution of this long - standing open problem in geometry . our computer - assisted proof relies on an enumeration of the irreducible contact graphs . . And you have already written the first three sentences of the full article: the _ kissing number _ @xmath6 is the highest number of equal non - overlapping spheres in @xmath7 that touch another sphere of the same size . in three dimensions the kissing number problem asks how many white billiard balls can _ kiss _ ( i.e. touch ) a black ball . the most symmetrical configuration , 12 balls around another , is achieved if the 12 balls are placed at positions corresponding to the vertices of a regular icosahedron concentric with the central ball . however , these 12 outer balls do not kiss one another and each may be moved freely . this space between the balls. Please generate the next two sentences of the article

prompts the question : _ if you moved all of them to one side , would a 13th ball fit ? _ this problem was the subject of the famous discussion between isaac newton and david gregory in 1694 . most reports say that newton believed the answer was 12 balls , while gregory thought that 13 might be possible .

Suppose that you have an abstract for a scientific paper: in this work , we have calculated the mass spectra and decay properties of dimesonic ( meson - antimeson ) bound state in the variational scheme . the intermesonic interaction considered as the hellmann potential and one pion exchange potential . the mass spectra of the @xmath0 , @xmath1 , @xmath2 , @xmath3 , @xmath4 , @xmath5 , @xmath6 , @xmath7 , @xmath8 , @xmath9 , @xmath10,@xmath11 , @xmath12 , @xmath13 , @xmath14 , @xmath15 , @xmath16 , @xmath17 etc .. are calculated . the states x(3872 ) , @xmath18 , @xmath19 and @xmath20 are compared with @xmath0 , @xmath4 , @xmath12 and @xmath15 dimesonic bound states . to probe the molecular structure of the compared states , we have calculated the decay properties sensitive to their long and short distance structure of hadorinc molecule , our results suggested the compared states driven the molecular structure . apart from these the other calculated mass spectra of dimesonoic states are predicted and for such bound states , the experimental search are suggested . pacs numbers : : 12.39.jh , 12.39.pn , 13.25.jx,14.40.rt . And you have already written the first three sentences of the full article: in 2003 , belle reported the discovery of a charmoiniumlike neutral states x(3872 ) with mass=@xmath21 mev with width @xmath22 mev @xcite and latter confirmed by do @xcite , cdf @xcite and barbar @xcite . this discovery fed excitement in the charmonium spectroscopy because of unconventional properties of the state . x(3872 ) could not be explained through ordinary meson(@xmath23 ) and baryon ( qqq ) scheme .. Please generate the next two sentences of the article

the conventional theories predicts complicated color neutral structures and search of such exotic structures are as old as quark model @xcite . after the discovery of x(3872 ) , the large number of charge , neutral and vector states have been detected in various experiments , famous as the xyz states . recently , the charge bottomoniumlike resonances @xmath24 and @xmath25 have been reported by belle collaboration in the process @xmath26 and @xmath27 @xcite . moreover

Suppose that you have an abstract for a scientific paper: using a lagrangian formalism , a three - parameter non - minimal einstein - maxwell theory is established . the three parameters , @xmath0 , @xmath1 and @xmath2 , characterize the cross - terms in the lagrangian , between the maxwell field and terms linear in the ricci scalar , ricci tensor , and riemann tensor , respectively . static spherically symmetric equations are set up , and the three parameters are interrelated and chosen so that effectively the system reduces to a one parameter only , @xmath3 . specific black hole and other type of one - parameter solutions are studied . first , as a preparation , the reissner - nordstrm solution , with @xmath4 , is displayed . then , we seek for solutions in which the electric field is regular everywhere as well as asymptotically coulombian , and the metric potentials are regular at the center as well as asymptotically flat . in this context , the one - parameter model with @xmath5 , @xmath6 , @xmath7 , called the gauss - bonnet model , is analyzed in detail . the study is done through the solution of the abel equation ( the key equation ) , and the dynamical system associated with the model . there is extra focus on an exact solution of the model and its critical properties . finally , an exactly integrable one - parameter model , with @xmath5 , @xmath8 , @xmath9 , is considered also in detail . a special sub - model , in which the fibonacci number appears naturally , of this one - parameter model is shown , and the corresponding exact solution is presented . interestingly enough , it is a soliton of the theory , the fibonacci soliton , without horizons and with a mild conical singularity at the center . . And you have already written the first three sentences of the full article: a natural and very general extension of the einstein - maxwell lagrangian yielding a general system of equations for a non - minimal coupling between the gravitational and electromagnetic fields , with non - linear terms , was set up and studied in @xcite . within this general theory , a special theory , worth of discussion , arises when one restricts the general lagrangian to a lagrangian that is einstein - hilbert in the gravity term , quadratic in the maxwell tensor , and the couplings between the electromagnetism and the metric are linear in the curvature terms . the motivations for setting up such a theory are phenomenological , see , e.g. , @xcite for reviews and references.this theory has three coupling constants @xmath0 , @xmath1 and @xmath2 , which characterize the cross - terms in the lagrangian between the maxwell field @xmath10 and terms linear in the ricci scalar @xmath11 , ricci tensor @xmath12 , and riemann tensor @xmath13 , respectively .. Please generate the next two sentences of the article

the coupling constants @xmath0 , @xmath1 and @xmath2 have units of area , and are a priori free parameters , which can acquire specific values in certain effective field theories . more specifically , the action functional of the non - minimal theory linear in the curvature is @xmath14 where @xmath15 is the determinant of the spacetime metric @xmath16 , and the lagrangian of the theory is @xmath17 here @xmath18 , @xmath19 being the gravitational constant and we are putting the velocity of light @xmath20 equal to one , @xmath21 is the maxwell tensor , with @xmath22 being the electromagnetic vector potential , and latin indexes are spacetime indexes , running from 0 to 3 .

Suppose that you have an abstract for a scientific paper: decoherence effects on the traditional @xmath0 vs. @xmath1 photon coherent control of a two - level system are investigated , with 1 vs. 3 used as a specific example . the problem reduces to that of a two - level system interacting with a single mode field , but with an effective rabi frequency that depends upon the fundamental and third harmonic fields . the resultant analytic control solution is explored for a variety of parameters , with emphasis on the dependence of control on the relative phase of the lasers . the generalization to off - resonant cases is noted . . And you have already written the first three sentences of the full article: coherent control of atomic and molecular dynamics using optical fields has attracted much attention , both theoretically and experimentally @xcite . thus far , most theoretical work has focused on the idealized case of isolated systems , where loss of quantum phase information due to decoherence , i.e. coupling to the environment , is ignored . such effects are , however , crucial to control in realistic systems , since loss of phase information results in loss of control . for this reason efforts to understand control in external environments @xcite @xcite and to compensate for the resultant decoherence ( e.g. , @xcite@xcite ) are of great interest . there exist a number of basic interference schemes@xcite that embody the essence of coherent control .. Please generate the next two sentences of the article

one is the @xmath0 vs. @xmath1 photon scenario where control results from interference between state excitation using @xmath0 and @xmath1 photons simultaneously . in this letter we provide an analytic solution for control in the two - level @xmath0 vs. @xmath1 photon control scenario in the presence of decoherence . for simplicity , we examine the 1 vs. 3 photon case , although the solutions obtained below apply equally well to the @xmath0 vs. @xmath1 photon case , with obvious changes in the input rabi frequencies and relative laser phases . in 1 vs. 3 photon control@xcite a continuous wave electromagnetic field composed of a superposition of a fundamental and third harmonic wave

Suppose that you have an abstract for a scientific paper: in this paper a neural networks based approach is presented to identify the noise in the virgo context . virgo is an experiment to detect gravitational waves by means of a laser interferometer . preliminary results appear to be very promising for data analysis of realistic interferometer outputs . . And you have already written the first three sentences of the full article: neural networks ( nn s ) have become in the last years a very effective instrument for solving many difficult problems in the field of signal processing due to their properties like non - linear dynamics , adaptability , self - organization and high speed computational capability ( see for example @xcite and the papers therein quoted ) . aim of this paper is to show the feasibility of the use of nn s to solve difficult problems of signal processing regarding the so called virgo project . gravitational waves ( gw s ) are travelling perturbations of the space - time predicted by the theory of general relativity , emitted when massive systems are accelerated .. Please generate the next two sentences of the article

up to now , there is only an indirect evidence of their existence , obtained by the observations of the binary pulsar system psr 1913 + 16 . moreover , the direct detection of gw s is not only a relevant test of general relativity , but the start of a new picture of the universe .

Suppose that you have an abstract for a scientific paper: barbarians , so named after the prototype of this class ( 234 ) barbara , are a rare class of asteroids exhibiting anomalous polarimetric properties . their very distinctive feature is that they show negative polarization at relatively large phase - angles , where all `` normal '' asteroids show positive polarization . the origin of the barbarian phenomenon is unclear , but it seems to be correlated with the presence of anomalous abundances of spinel , a mineral usually associated with the so - called calcium aluminum - rich inclusions ( cais ) on meteorites . since cais are samples of the oldest solid matter identified in our solar system , barbarians are very interesting targets for investigations . inspired by the fact that some of the few known barbarians are members of , or very close to the dynamical family of watsonia , we have checked whether this family is a major repository of barbarians , in order to obtain some hints about their possible collisional origin . we have measured the linear polarization of a sample of nine asteroids which are members of the watsonia family within the phase - angle range @xmath0 . we found that seven of them exhibit the peculiar barbarian polarization signature , and we conclude that the watsonia family is a repository of barbarian asteroids . the new barbarians identified in our analysis will be important to confirm the possible link between the barbarian phenomenon and the presence of spinel on the surface . [ firstpage ] asteroids : general polarization . . And you have already written the first three sentences of the full article: the degree of linear polarization of sunlight scattered by an asteroid toward an observer depends on the phase - angle , namely the angle between the asteroid - sun and the asteroid - observer directions . the phase - polarization curves of all atmosphereless bodies of the solar system exhibit qualitatively similar trends , but their detailed features vary according to the specific properties ( including primarily the geometric albedo ) of individual surfaces . in the phase - angle range @xmath1 , asteroids exhibit the so - called branch of _ negative polarization _ , in which , in contrast to what is expected from simple single rayleigh - scattering or fresnel - reflection mechanisms , the plane of linear polarization turns out to be parallel to the plane of scattering ( the plane including the sun , the target and the observer ) .. Please generate the next two sentences of the article

the plane of linear polarization becomes perpendicular to the scattering plane , a situation commonly described as _ positive polarization _ , at phase angle values larger than the so - called _ inversion angle _ , which is generally around @xmath2 .

Suppose that you have an abstract for a scientific paper: we report on the fabrication and diffraction - limited characterization of parabolic focusing micromirrors . sub micron beam waists are measured for mirrors with 10-@xmath0 m radius aperture and measured fixed focal lengths in the range from 24 @xmath0 m to @xmath1 m . optical characterization of the 3d intensity in the near field produced when the device is illuminated with collimated light is performed using a modified confocal microscope . results are compared directly with angular spectrum simulations , yielding strong agreement between experiment and theory , and identifying the competition between diffraction and focusing in the regime probed . 99 h. c. king , _ the history of the telescope _ ( dover , 2003 ) . l. novotny , and b. hecht , _ principles of nano - optics _ ( cambridge university , 2012 ) . w. r. jamroz , r. kruzelecky , and e. i. haddad , _ applied microphotonics _ ( taylor & francis , 2006 ) . r. vlkel , m. eisner , and k.j . weible , `` miniaturized imaging systems , '' microelectron . eng . * 67 * , 461 - 472 ( 2003 ) . m. trupke , e. a. hinds , s. eriksson , e. a. curtis , . moktadir , e. kukharenka , and m. kraft `` microfabricated high - finesse optical cavity with open access and small volume , '' appl . phys . lett . * 87 * , 211106 ( 2005 ) . f. merenda , j rohner , j .- m . fournier , and r .- p . salath `` miniaturized high - na focusing - mirror multiple optical tweezers , '' opt . express * 15 * , 6075 - 6086 ( 2007 ) . f. merenda , m. grossenbacher , s. jeney , l. forr , and r .- p . salath `` three - dimensional force measurements in optical tweezers formed with high - na micromirrors , '' opt . lett . * 34 * , 1063 - 1065 ( 2009 ) .. y. s. ow , m. b. h. breese , and sara azimi `` fabrication of concave silicon micro - mirrors , '' opt . express * 18 * , 14511 - 14518 ( 2010 ) . g. w. biedermann , f. m. benito , k. m. fortier , d. l. stick , t. k. loyd , p. d. d. schwindt , c. y. nakakura ,.... And you have already written the first three sentences of the full article: the introduction of reflective optical elements revolutionized the design and imaging capabilities of telescopes @xcite . while the possibility of creating large diameter objectives was one of the primary aims , a significant advantage is that reflective optical elements provide a means of reducing or eliminating the spherical and chromatic aberrations that are inherent in lens based systems . here we explore the opposite extreme of microfabricated optics .. Please generate the next two sentences of the article

microfabricated optical elements are key components for the development and integration of optics into a range of research and commercial areas @xcite . to date , the majority of the work in microphotonics has been in refractive elements , i.e. microlenses . however , in this regime microlenses typically have significant numerical apertures and surface curvatures , which introduce large aberrations .

Suppose that you have an abstract for a scientific paper: we introduce an ising approach to study the spread of malware . the ising spins up and down are used to represent two states online and offline of the nodes in the network . malware is allowed to propagate amongst online nodes and the rate of propagation was found to increase with data traffic . for a more efficient network , the spread of infection is much slower ; while for a congested network , infection spreads quickly . computer networks ; computer viruses ; epidemiology . And you have already written the first three sentences of the full article: the internet has become a near indispensable tool with both private individuals and organizations becoming increasingly dependent on internet - based software services , downloadable resources like books and movies , online shopping and banking , and even social networking sites . the issue of network security has become significant due to the prevalence of software with malicious or fraudulent intent . malware is the general term given to a broad range of software including viruses and worms designed to infiltrate a computer system without the owner s permission @xcite@xcite .. Please generate the next two sentences of the article

cohen s conclusion in his 1987 paper that computer viruses are potentially a severe threat to computer systems @xcite is still valid in real networks today @xcite@xcite@xcite . current security systems do little to control the spread of malicious content throughout an entire network @xcite@xcite .

Suppose that you have an abstract for a scientific paper: dipole models based on various saturation scenarios provide reasonable fits to small - x dis inclusive , diffractive and exclusive data from hera . proton un - integrated gluon distributions extracted from such fits are employed in a @xmath0-factorization framework to calculate inclusive gluon distributions at various energies . the n - particle multiplicity distribution predicted in the glasma flux tube approach shows good agreement with data over a wide range of energies . hadron inclusive transverse momentum distributions expressed in terms of the saturation scale demonstrate universal behavior over a wider kinematic range systematically with increasing center of mass energies . saturation ; lhc p + p collision ; cgc ; deep inelastic scattering . And you have already written the first three sentences of the full article: hera deeply inelastic scattering ( dis ) results on structure functions demonstrate a rapid bremsstrahlung growth of the gluon density at small x. when interpreted in the same framework as the parton model , this growth is predicted to saturate because the gluon occupation number in hadron wave functions saturate at a value maximally of order @xmath1 ; dynamically , nonlinear effects such as gluon recombination and screening by other gluons deplete the growth of the gluon distribution@xcite . gluon modes with @xmath2 are maximally occupied , where @xmath3 is a dynamically generated semi - hard scale called the saturation scale . for small @xmath4 , @xmath5 is large enough that high occupancy states can be described by weak coupling classical effective theory@xcite . this color glass condensate description of high energy hadrons and nuclei is universal and has been tested in both dis and hadronic collisions .. Please generate the next two sentences of the article

in particular , saturation based phenomenological predictions successfully describe recent lhc p+p data @xcite and predict possible geometrical scaling of transverse momentum distribution@xcite similar to the geometrical scaling observed previously in dis . the object common to dis and hadronic collisions is the dipole cross section @xmath6 . in the cgc framework , the dipole cross section can be expressed in terms of expectation values of correlators of wilson lines representing the color fields of the target .

Suppose that you have an abstract for a scientific paper: it is known that the meissner - like effect is seen in a magnetosphere without an electric current in black hole spacetime : no non - monopole component of magnetic flux penetrates the event horizon if the black hole is extreme . in this paper , in order to see how an electric current affects the meissner - like effect , we study a force - free electromagnetic system in a static and spherically symmetric extreme black hole spacetime . by assuming that the rotational angular velocity of the magnetic field is very small , we construct a perturbative solution for the grad - shafranov equation , which is the basic equation to determine a stationary , axisymmetric electromagnetic field with a force - free electric current . our perturbation analysis reveals that , if an electric current exists , higher multipole components may be superposed upon the monopole component on the event horizon , even if the black hole is extreme . . And you have already written the first three sentences of the full article: it is widely believed that there are supermassive black holes at the centers of galaxies , and these are hypothesized to be the central engines for active galactic nuclei ( agns ) and gamma ray bursts ( grbs ) . two main possibilities are considered as the energy source . one is the gravitational energy of accreting matter and the other is the rotational energy of the black hole or the accretion disk surrounding it .. Please generate the next two sentences of the article

however , the details of the energy extraction process are not clear . it is also not understood well how the energy is converted into that of agns or grbs .

Suppose that you have an abstract for a scientific paper: we develop a theory of parametric resonance in tunable superconducting cavities . the nonlinearity introduced by the squid attached to the cavity , and damping due to connection of the cavity to a transmission line are taken into consideration . we study in detail the nonlinear classical dynamics of the cavity field below and above the parametric threshold for the degenerate parametric resonance , featuring regimes of multistability and parametric radiation . we investigate the phase - sensitive amplification of external signals on resonance , as well as amplification of detuned signals , and relate the amplifier performance to that of linear parametric amplifiers . we also discuss applications of the device for dispersive qubit readout . beyond the classical response of the cavity , we investigate small quantum fluctuations around the amplified classical signals . we evaluate the noise power spectrum both for the internal field in the cavity and the output field . other quantum statistical properties of the noise are addressed such as squeezing spectra , second order coherence , and two - mode entanglement . . And you have already written the first three sentences of the full article: parametric resonance is a fundamental physical phenomenon that is encountered eventually in every area of science . in different disciplines , however , different facets of this rich phenomenon play a major role and are highlighted . parametric instability and multistable regimes in nonlinear dynamics @xcite , noise driven transitions among stable states in statistical physics @xcite , wave mixing and frequency conversion in wave dynamics @xcite are topics of primary interest . in electrical and optical engineering the low - noise properties of parametric amplifiers attract attentions , as well as non - classical statistical properties of the electromagnetic field generated by parametric devices @xcite . in superconducting electronics ,. Please generate the next two sentences of the article

the idea of using josephson junctions for quantum limited parametric amplification is under attention and development since the 1980s @xcite . during the last years the field revived by challenges of quantum information technology . the circuit - qed design , initially proposed for qubit manipulation and measurement @xcite , was employed for developing a variety of parametric devices @xcite .

Suppose that you have an abstract for a scientific paper: statistical mechanics of two coupled vector fields is studied in the tight - binding model that describes propagation of polarized light in discrete waveguides in the presence of the four - wave mixing . the energy and power conservation laws enable the formulation of the equilibrium properties of the polarization state in terms of the gibbs measure with positive temperature . the transition line @xmath0 is established beyond which the discrete vector solitons are created . also in the limit of the large nonlinearity an analytical expression for the distribution of stokes parameters is obtained which is found to be dependent only on the statistical properties of the initial polarization state and not on the strength of nonlinearity . the evolution of the system to the final equilibrium state is shown to pass through the intermediate stage when the energy exchange between the waveveguides is still negligible . the distribution of the stokes parameters in this regime has a complex multimodal structure strongly dependent on the nonlinear coupling coefficients and the initial conditions . . And you have already written the first three sentences of the full article: the equilibrium behavior and the equipartition of energy between various degrees of freedom in nonlinear , nonintegrable discrete systems has attracted considerable interest since the seminal study of fermi , pasta and ulam @xcite . in hamiltonain systems with conserved number of excitations ( waves ) the maximum entropy principle suggests that in the final state of thermal equilibrium the statistics of the system is given by grand canonical gibbs distribution with the effective `` temperature '' and `` chemical potential '' @xcite . however unlike the conventional statistical mechanics the effective temperature of this grand - canonical distribution depends on the initial position in the phase space and for certain regions can become negative making the distribution non - normalizable .. Please generate the next two sentences of the article

such regime is commonly attributed to the emergence of stable , localized , nonlinear structures corresponding to solitons in continuous systems @xcite and discrete breathers @xcite in discrete systems . from the point of view of the wave turbulence theory @xcite the resulting equilibrium distribution provides stationary rayleigh - jeans spectra @xcite .

Suppose that you have an abstract for a scientific paper: we reconstruct the equation of state @xmath0 of dark energy ( de ) using a recently released data set containing 172 type ia supernovae without assuming the prior @xmath1 ( in contrast to previous studies ) . we find that dark energy evolves rapidly and metamorphoses from dust - like behaviour at high @xmath2 ( @xmath3 at @xmath4 ) to a strongly negative equation of state at present ( @xmath5 at @xmath6 ) . dark energy metamorphosis appears to be a robust phenomenon which manifests for a large variety of sne data samples provided one does not invoke the weak energy prior @xmath7 . invoking this prior considerably weakens the rate of growth of @xmath0 . these results demonstrate that dark energy with an evolving equation of state provides a compelling alternative to a cosmological constant if data are analysed in a prior - free manner and the weak energy condition is not imposed by hand . cosmology : theory cosmological parameters statistics . And you have already written the first three sentences of the full article: one of the most tantalizing observational discoveries of the past decade has been that the expansion of the universe is speeding up rather than slowing down . an accelerating universe is strongly suggested by observations of type ia high redshift supernovae provided these behave as standard candles . the case for an accelerating universe is further strengthened by the discovery of cosmic microwave background ( cmb ) anisotropies on degree scales ( which indicate @xmath8 ) combined with a low value for the density in clustered matter @xmath9 deduced from galaxy redshift surveys .. Please generate the next two sentences of the article

all three sets of observations strongly suggest that the universe is permeated by a relatively smooth distribution of ` dark energy ' ( de ) which dominates the density of the universe ( @xmath10 ) and whose energy momentum tensor violates the strong energy condition ( @xmath11 ) so that @xmath12 . although a cosmological constant ( @xmath13 ) provides a plausible answer to the conundrum posed by dark energy , it is well known that the unevolving cosmological constant faces serious ` fine tuning ' problems since the ratio between @xmath14 and the radiation density , @xmath15 , is already a miniscule @xmath16 at the electroweak scale ( @xmath17 gev ) and even smaller , @xmath18 , at the planck scale ( @xmath19 gev ) .

Suppose that you have an abstract for a scientific paper: we present hybrid openmp / mpi ( open multi - processing / message passing interface ) parallelized versions of earlier published c programs ( d. vudragovi et al . ( 2012 ) @xcite ) for calculating both stationary and non - stationary solutions of the time - dependent gross - pitaevskii ( gp ) equation in three spatial dimensions . the gp equation describes the properties of dilute bose - einstein condensates at ultra - cold temperatures . hybrid versions of programs use the same algorithms as the c ones , involving real- and imaginary - time propagation based on a split - step crank - nicolson method , but consider only a fully - anisotropic three - dimensional gp equation , where algorithmic complexity for large grid sizes necessitates parallelization in order to reduce execution time and/or memory requirements per node . since distributed memory approach is required to address the latter , we combine mpi programing paradigm with existing openmp codes , thus creating fully flexible parallelism within a combined distributed / shared memory model , suitable for different modern computer architectures . the two presented c / openmp / mpi programs for real- and imaginary - time propagation are optimized and accompanied by a customizable makefile . we present typical scalability results for the provided openmp / mpi codes and demonstrate almost linear speedup until inter - process communication time starts to dominate over calculation time per iteration . such a scalability study is necessary for large grid sizes in order to determine optimal number of mpi nodes and openmp threads per node . bose - einstein condensate ; gross - pitaevskii equation ; split - step crank - nicolson scheme ; real- and imaginary - time propagation ; c program ; mpi ; openmp ; partial differential equation 02.60.lj ; 02.60.jh ; 02.60.cb ; 03.75.-b * new version program summary * + _ program title : _ gp - scl - hyb package , consisting of : ( i ) imagtime3d - hyb , ( ii ) realtime3d - hyb . + _ catalogue.... And you have already written the first three sentences of the full article: b. s. , v. s. , a. b. , and a. b. acknowledge support by the ministry of education , science , and technological development of the republic of serbia under projects on171017 , iii43007 , on171009 , on174027 and ibec , and by daad - german academic and exchange service under project ibec . m. acknowledges support by the science and engineering research board , department of science and technology , government of india under project no . s. k. a. acknowledges support by the cnpq of brazil under project 303280/2014 - 0 , and by the fapesp of brazil under project 2012/00451 - 0 .. Please generate the next two sentences of the article

numerical simulations were run on the paradox supercomputing facility at the scientific computing laboratory of the institute of physics belgrade , supported in part by the ministry of education , science , and technological development of the republic of serbia under project on171017 . d. vudragovi , i. vidanovi , a. bala , p. muruganandam , s. k. adhikari , c programs for solving the time - dependent gross - pitaevskii equation in a fully anisotropic trap , comput .

Suppose that you have an abstract for a scientific paper: in this report , we simulate practical feature of yuen - kim protocol for quantum key distribution with unconditional secure . in order to demonstrate them experimentally by intensity modulation / direct detection(imdd ) optical fiber communication system , we use simplified encoding scheme to guarantee security for key information(1 or 0 ) . that is , pairwise m - ary intensity modulation scheme is employed . furthermore , we give an experimental implementation of yk protocol based on imdd . . And you have already written the first three sentences of the full article: it is well known that quantum key distribution is one of the most interesting subjects in quantum information science , which was pioneered by c.bennett and g.brassard in 1984[1 ] . in the original paper of bennett , single photon communication was employed as implementation of quantum key distribution . however , despite that it is not essential in great idea of bennett , many researchers employed single photon communication scheme to realize bb84 , b92[2 ] . because of the difficulties of single photon communication in practical sense , it was discussed whether one can realize a secure key distribution guaranteed by quantum nature based on light wave communication or not . in 1998 , h.p.yuen and a.kim[3 ] proposed another scheme for key distribution based on communication theory(signal detection theory ) .. Please generate the next two sentences of the article

this scheme corresponds to an implementation of secret key sharing which was information theoretically predicted by maurer[4 ] , et al . however , yuen s idea was found independently from maurer s discussion . in the first paper of yuen - kim[3 ] , they showed that if noises of eve(eavesdropper ) and bob(receiver ) are statistically independent , secure key distribution can be realized even if they are classical noises , in which they employed a modification of b92 protocol[2 ] . following yk s first paper ,

Suppose that you have an abstract for a scientific paper: we prove several results detecting cyclicity or nilpotency of a finite group @xmath0 in terms of inequalities involving the orders of the elements of @xmath0 and the orders of the elements of the cyclic group of order @xmath1 . we prove that , among the groups of the same order , the number of cyclic subgroups is minimal for the cyclic group and the product of the orders of the elements is maximal for the cyclic group . . And you have already written the first three sentences of the full article: in this paper all groups are assumed to be finite . the problem of detecting structural properties of a finite group by looking at element orders has been considered by various authors . amiri , jafarian amiri and isaacs in @xcite proved that the sum of element orders of a finite group @xmath0 of order @xmath2 is maximal in the cyclic group of order @xmath2 .. Please generate the next two sentences of the article

the problem of minimizing sums of the form @xmath3 , where @xmath4 is a positive integer and @xmath5 denotes the order of @xmath6 , was considered in @xcite , however there is a mistake in the proof pointed out by isaacs in @xcite . the main point of the argument in @xcite is a pointwise argument , and the strong evidence that it is true suggests to state it as a conjecture .

Suppose that you have an abstract for a scientific paper: in this paper we study pairs of polynomials with a given factorization pattern and such that the degree of their difference attains its minimum . we call such pairs of polynomials _ davenport zannier pairs _ , or dz - pairs for short . the paper is devoted to the study of dz - pairs _ with rational coefficients_. in our earlier paper @xcite , in the framework of the _ theory of dessins denfants _ , we established a correspondence between dz - pairs and _ weighted bicolored plane trees_. these are bicolored plane trees whose edges are endowed with positive integral weights . when such a tree is uniquely determined by the set of black and white degrees of its vertices , it is called _ unitree _ , and the corresponding dz - pair is defined over @xmath0 . in @xcite , we classified all unitrees . in this paper , we compute all the corresponding polynomials . in this way , the present paper is a sequel of @xcite . in the final part of the paper we present some additional material concerning the galois theory of dz - pairs and weighted trees . . And you have already written the first three sentences of the full article: let @xmath1 be two partitions of an integer @xmath2 , @xmath3 and let @xmath4 and @xmath5 be two _ coprime _ polynomials of degree @xmath2 having the following factorization patterns : @xmath6 in these expressions we consider the multiplicities @xmath7 and @xmath8 , @xmath9 , @xmath10 as being given , while the roots @xmath11 and @xmath12 are not fixed , though they must all be distinct . in this paper we study polynomials satisfying ( [ eq : p - and - q ] ) and such that _ the degree of their difference @xmath13 attains its minimum_. numerous papers , mainly in number theory , were devoted to the study of such polynomials . [ assump ] throughout the paper , we always assume that * the greatest common divisor of the numbers @xmath14 is 1 ; * @xmath15 . the case of partitions @xmath16 , @xmath17 not satisfying the above conditions can easily be reduced to this case ( see @xcite ) . in 1995 ,. Please generate the next two sentences of the article

zannier @xcite proved that under the above conditions the following statements hold : 1 . this bound is always attained , whatever are @xmath16 and @xmath17 .

Suppose that you have an abstract for a scientific paper: the temperature - driven reorientation transition which , up to now , has been studied by use of heisenberg - type models only , is investigated within an itinerant - electron model . we consider the hubbard model for a thin fcc(100 ) film together with the dipole interaction and a layer - dependent anisotropy field . the isotropic part of the model is treated by use of a generalization of the spectral - density approach to the film geometry . the magnetic properties of the film are investigated as a function of temperature and film thickness and are analyzed in detail with help of the spin- and layer - dependent quasiparticle density of states . by calculating the temperature dependence of the second - order anisotropy constants we find that both types of reorientation transitions , from out - of - plane to in - plane ( `` fe - type '' ) and from in - plane to out - of - plane ( `` ni - type '' ) magnetization are possible within our model . in the latter case the inclusion of a positive volume anisotropy is vital . the reorientation transition is mediated by a strong reduction of the surface magnetization with respect to the inner layers as a function of temperature and is found to depend significantly on the total band occupation . -4 mm . And you have already written the first three sentences of the full article: the large variety of novel and interesting phenomena of thin - film magnetism results very much from the fact that the magnetic anisotropy , which determines the easy axis of magnetization , can be one or two orders of magnitude larger than in the corresponding bulk systems@xcite . the reorientation transition ( rt ) of the direction of magnetization in thin ferromagnetic films describes the change of the easy axis by variation of the film thickness or temperature and has been widely studied both experimentally @xcite and theoretically @xcite . an instructive phenomenological picture for the understanding of the rt is obtained by expanding the free energy @xmath0 of the system in powers of @xmath1 , where @xmath2 is the angle between the direction of magnetization and the surface normal .. Please generate the next two sentences of the article

neglecting azimuthal anisotropy and exploiting time inversion symmetry yields : @xmath3 the anisotropy coefficients of second ( @xmath4 ) and fourth ( @xmath5 ) order depend on the thickness @xmath6 of the film as well as on the temperature @xmath7 . away from the transition point usually @xmath8 holds , and , therefore , the direction of magnetization is determined by the sign of @xmath4 ( @xmath9 : out - of - plane magnetization ; @xmath10 : in - plane magnetization ) . on this basis

Suppose that you have an abstract for a scientific paper: we study the interplay of clumping at small scales with the collapse and relaxation of perturbations at much larger scales . we present results of our analysis when the large scale perturbation is modelled as a plane wave . we find that in absence of substructure , collapse leads to formation of a pancake with multi - stream regions . dynamical relaxation of plane wave is faster in presence of substructure . scattering of substructures and the resulting enhancement of transverse motions of haloes in the multi - stream region lead to a thinner pancake . in turn , collapse of the plane wave leads to formation of more massive collapsed haloes as compared to the collapse of substructure in absence of the plane wave . the formation of more massive haloes happens without any increase in the total mass in collapsed haloes . a comparison with the burgers equation approach in absence of any substructure suggests that the preferred value of effective viscosity depends primarily on the number of streams in a region . gravitation cosmology : theory dark matter , large scale structure of the universe . And you have already written the first three sentences of the full article: large scale structures like galaxies and clusters of galaxies are believed to have formed by gravitational amplification of small perturbations @xcite . observations suggest that the initial density perturbations were present at all scales that have been probed by observations . an essential part of the study of formation of galaxies and other large scale structures is thus the evolution of density perturbations for such initial conditions .. Please generate the next two sentences of the article

once the amplitude of perturbations at any scale becomes large , i.e. , @xmath0 , the perturbation becomes non - linear and the coupling with perturbations at other scales can not be ignored . indeed , understanding the interplay of density perturbations at different scales is essential for developing a full understanding of gravitational collapse in an expanding universe . the basic equations for this have been known for a long time @xcite but apart from some special cases , few solutions are known .

Suppose that you have an abstract for a scientific paper: today , prime numbers attained exceptional situation in the area of numbers theory and cryptography . as we know , the trend for accessing to the largest prime numbers due to using mersenne theorem , although resulted in vast development of related numbers , however it has reduced the speed of accessing to prime numbers from one to five years . this paper could attain to theorems that are more extended than mersenne theorem with accelerating the speed of accessing to prime numbers . since that time , the reason for frequently using mersenne theorem was that no one could find an efficient formula for accessing to the largest prime numbers . this paper provided some relations for prime numbers that one could define several formulas for attaining prime numbers in any interval ; therefore , according to flexibility of these relations , it could be found a new branch in the field of accessing to great prime numbers followed by providing an algorithm at the end of this paper for finding the largest prime numbers . . And you have already written the first three sentences of the full article: due to the importance of the primes , the mathematicians have been investigating about them since long centuries ago . in 1801 , carl gauss , one of the greatest mathematician , submitted that the problem of distinguishing the primes among the non - primes has been one of the outstanding problems of arithmetic @xcite . proving the infinity of prime numbers by euclid is one of the first and most brilliant works of the human being in the numbers theory @xcite .. Please generate the next two sentences of the article

greek people knew prime numbers and were aware of their role as building blocks of other numbers . more , the most natural question asked by human being was this what order prime numbers are following and how one could find prime numbers ? until this time , there have been more attempts for finding a formula producing the prime numbers and or a model for appearance of prime numbers among other numbers and although they could be more helpful for developing the numbers theory , however , the complicated structure of prime numbers could not be decoded . during last years

Suppose that you have an abstract for a scientific paper: a lattice qcd calculation of the @xmath0 decay form factors is presented . we obtain the value of the form factor @xmath1 at the zero - recoil limit @xmath2 with high precision by considering a ratio of correlation functions in which the bulk of the uncertainties cancels . the other form factor @xmath3 is calculated , for small recoil momenta , from a similar ratio . in both cases , the heavy quark mass dependence is observed through direct calculations with several combinations of initial and final heavy quark masses . our results are @xmath4 and @xmath5 . for both the first error is statistical , the second stems from the uncertainty in adjusting the heavy quark masses , and the last from omitted radiative corrections . combining these results , we obtain a precise determination of the physical combination @xmath6 , where the mentioned systematic errors are added in quadrature . the dependence on lattice spacing and the effect of quenching are not yet included , but with our method they should be a fraction of @xmath7 . . And you have already written the first three sentences of the full article: the precise determination of the cabibbo - kobayashi - maskawa ( ckm ) matrix element @xmath8 is a crucial step for @xmath9 physics to pursue phenomena beyond the standard model . in particular , the precision achieved in determining the apex of the unitarity triangle may be limited by @xmath10 , even with future high - statistics experiments . the current determination of @xmath10 @xcite is made through inclusive @xcite and exclusive @xcite @xmath9 decays .. Please generate the next two sentences of the article

the heavy quark expansion offers a method to evaluate the hadronic transition amplitude in a systematic way . in particular , at the kinematic end point the exclusive @xmath11 matrix element is normalized in the infinite heavy quark mass limit , and the correction of order @xmath12 vanishes as a consequence of luke s theorem @xcite .

Suppose that you have an abstract for a scientific paper: we report the thermodynamic properties of bose and fermi ideal gases immersed in periodic structures such as penetrable multilayers or multitubes simulated by one ( planes ) or two perpendicular ( tubes ) external dirac comb potentials , while the particles are allowed to move freely in the remaining directions . although the bosonic chemical potential is a constant for @xmath0 , a non decreasing with temperature anomalous behavior of the fermionic chemical potential is confirmed and monitored as the tube bundle goes from 2d to 1d when the wall impenetrability overcomes a critical value . in the specific heat curves dimensional crossovers are very noticeable at high temperatures for both gases , where the system behavior goes from 3d to 2d and latter to 1d as the wall impenetrability is increased . . And you have already written the first three sentences of the full article: non - relativistic quantum fluids ( fermions or bosons ) constrained by periodic structures , such as layered or tubular , are found in many real or man - made physical systems . for example , we find electrons in layered structures such as cuprate high temperature superconductors or semiconductor superlattices , or in tubular structures like organo - metalic superconductors . on the experimental side , there are a lot of experiments around bosonic gases in low dimensions , such as : bec in 2d hydrogen atoms @xcite , 2d bosonic clouds of rubidium @xcite , superfluidity in 2d @xmath1he films @xcite , while for in 1d we have the confinement of sodium @xcite , to mention a few .. Please generate the next two sentences of the article

meanwhile , for non - interacting fermions there are only a few experiments , for example , interferometry probes which have led to observe bloch oscillations @xcite . to describe the behavior of fermion and boson gases inside this symmetries , several works have been published . for a review of a boson gas in optical lattices

Suppose that you have an abstract for a scientific paper: a framework for performing dynamic mesh adaptation with the discontinuous galerkin method ( dgm ) is presented . adaptations include modifications of the local mesh step size ( @xmath0-adaptation ) and the local degree of the approximating polynomials ( @xmath1-adaptation ) as well as their combination . the computation of the approximation within locally adapted elements is based on projections between finite element spaces ( fes ) , which are shown to preserve an upper limit of the electromagnetic energy . the formulation supports high level hanging nodes and applies precomputation of surface integrals for increasing computational efficiency . error and smoothness estimates based on interface jumps are presented and applied to the fully @xmath2-adaptive simulation of two examples in one - dimensional space . a full wave simulation of electromagnetic scattering form a radar reflector demonstrates the applicability to large scale problems in three - dimensional space . discontinuous galerkin method , dynamic mesh adaptation , @xmath2-adaptation , maxwell time - domain problem , large scale simulations 65m60 , 78a25 . And you have already written the first three sentences of the full article: the discontinuous galerkin method @xcite nowadays is a well - established method for solving partial differential equations , especially for time - dependent problems . it has been thoroughly investigated by cockburn and shu as well as hesthaven and warburton , who summarized many of their findings in @xcite and @xcite , respectively . concerning maxwell s equations in time - domain , the dgm has been studied in particular in @xcite .. Please generate the next two sentences of the article

the former two apply tetrahedral meshes , which provide flexibility for the generation of meshes also for complicated structures . the latter two make use of hexahedral meshes , which allow for a computationally more efficient implementation @xcite . in @xcite the authors state that the method can easily deal with meshes with hanging nodes since no inter - element continuity is required , which renders it particularly well suited for @xmath2-adaptivity .

Suppose that you have an abstract for a scientific paper: we consider discrete metric spaces and we look for nonconstant contractions . we introduce the notion of contractive map and we characterize the spaces with nonconstant contractive maps . we provide some examples to discussion the possible relations between contractions , contractive maps and constant functions . finally we apply the main result to the subgraphs of a nonoriented , connected graph . .6 cm * keywords * : discrete metric space , contractive map , contraction , fixed point , nonoriented graph * ams subject classification * : 47h09 , 54e99 . . And you have already written the first three sentences of the full article: let us consider the following question : a group of people , living in the same country , but in different places , want to move in such a way that the distance among any two of them strictly decreases . unfortunately they can not all fit into one single house . hence , the constraints are : a. anyone can either move from his place to another one s ( no matter what the owner of the `` destination house '' does ) or stay where he is , b. they can not all move to the same place .. Please generate the next two sentences of the article

is it possible for them to move ? this question is a particular case of a more interesting problem involving discrete , possibly infinite , metric spaces ( we will come back to the original problem in section [ sec : conclusions ] at the end of the paper ) .

Suppose that you have an abstract for a scientific paper: employing graphites having distinctly different mean grain sizes , we study the effects of polycrystallinity on the pattern formation by ion - beam - sputtering . the grains influence the growth of the ripples in highly anisotropic fashion ; both the mean uninterrupted ripple length along its ridge and the surface width depend on the mean size of the grains , which is attributed to the large sputter yield at the grain boundary compared with that on terrace . in contrast , the ripple wavelength does not depend on the mean size of the grains . coarsening of the ripples - accompanying the mass transport across the grain boundaries - should not be driven by thermal diffusion , rather by ion - induced processes . . And you have already written the first three sentences of the full article: incidence of energetic ion - beam causes the displacement and even removal of atoms near the surface . these whole processes are conventionally referred to as ion - beam - sputtering ( ibs ) . simultaneously , the healing kinetics proceeds via mass transport to minimize the surface free energy of the modified surface .. Please generate the next two sentences of the article

those two competing processes often produce patterns of nano - dots / holes or ripples depending on the incidence angle of the ion - beam . ibs is one of the most versatile tools to fabricate nano patterns in various sizes and shapes by controlling physical variables , and applicable to a wide range of materials from metals , insulators to organic materials .

Suppose that you have an abstract for a scientific paper: we report ultrafast transient - grating measurements of crystals of the three - dimensional dirac semimetal cadmium arsenide , cd@xmath0as@xmath1 , at both room temperature and 80 k. after photoexcitation with 1.5-ev photons , charge - carriers relax by two processes , one of duration 500 fs and the other of duration 3.1 ps . by measuring the complex phase of the change in reflectance , we determine that the faster signal corresponds to a decrease in absorption , and the slower signal to a decrease in the light s phase velocity , at the probe energy . we attribute these signals to electrons filling of phase space , first near the photon energy and later at lower energy . we attribute their decay to cooling by rapid emission of optical phonons , then slower emission of acoustic phonons . we also present evidence that both the electrons and the lattice are strongly heated . + + the following article appeared in _ applied physics letters _ and may be found at + http://scitation.aip.org/content/aip/journal/apl/106/23/10.1063/1.4922528 + ( this version of the article differs slightly from the published one . ) + + _ copyright 2015 american institute of physics . this article may be downloaded for personal use only . any other use requires prior permission of the author and the american institute of physics . _ . And you have already written the first three sentences of the full article: cadmium arsenide , known for decades as an inverted - gap semiconductor , has recently been shown to be a three - dimensional dirac semimetal . these materials , with a massless dirac dispersion throughout the bulk , are the 3d analogs of graphene , and cd@xmath0as@xmath1 is foremost among them : stable , high - mobility , and nearly stoichiometric . it displays giant magnetoresistance , hosts topologically nontrivial fermi - arc states on its surface , and is predicted to serve as a starting point from which to realize a weyl semimetal , quantum spin hall insulator , or axion insulator .. Please generate the next two sentences of the article

ultrafast spectroscopy , which monitors changes in a sample s optical properties after excitation by a short laser pulse , has in many materials provided a time - resolved probe of basic carrier relaxation processes such as electron - electron and electron - phonon scattering and carrier diffusion . calculations for dirac and weyl semimetals predict that photoexcited electrons will , anomalously , cool linearly with time once their elergy drops below that of the lowest optical phonon .

Suppose that you have an abstract for a scientific paper: we analyze a controversial topic about the universality class of the three - dimensional ising model with long - range - correlated disorder . whereas both theoretical and numerical studies agree on the validity of extended harris criterion ( a. weinrib , b.i . halperin , phys . rev . b 27 ( 1983 ) 413 ) and indicate the existence of a new universality class , the numerical values of the critical exponents found so far differ essentially . to resolve this discrepancy we perform extensive monte carlo simulations of a 3d ising model with non - magnetic impurities being arranged in a form of lines along randomly chosen axes of a lattice . the swendsen - wang algorithm is used alongside with a histogram reweighting technique and the finite - size scaling analysis to evaluate the values of critical exponents governing the magnetic phase transition . our estimates for these exponents differ from both previous numerical simulations and are in favour of a non - trivial dependency of the critical exponents on the peculiarities of long - range correlations decay . , , , random ising model , long - range - correlated disorder , monte carlo , critical exponents 05.10.ln , 64.60.fr , 75.10.hk . And you have already written the first three sentences of the full article: critical properties of structurally disordered magnets remain a problem of great interest in condensed matter physics , as far as real magnetic crystals are usually non - ideal . commonly , in the theoretical studies , as well as in the mc simulations , one considers point - like uncorrelated quenched non - magnetic impurities @xcite . however , in real magnets one encounters non - idealities of structure , which can not be modeled by simple point - like uncorrelated defects .. Please generate the next two sentences of the article

indeed , magnetic crystals often contain defects of a more complex structure : linear dislocations , planar grain boundaries , three - dimensional cavities or regions of different phases , embedded in the matrix of the original crystal , as well as various complexes ( clusters ) of point - like non - magnetic impurities @xcite . therefore , a challenge is to offer a consistent description of the critical phenomena influenced by the presence of such complicated defects .

Suppose that you have an abstract for a scientific paper: we report on observations of the x - ray pulsar by the lecs instrument on - board _ bepposax_. we confirm the recent asca discovery of excess emission near 1 kev ( angelini et al . 1995 ) . the pulse period of 7.66794 @xmath0 0.00004 s indicates that the source continues to spin - down . the phase averaged spectrum is well fit by an absorbed power - law of photon index 0.61 @xmath0 0.02 and a blackbody of temperature 0.33 @xmath0 0.02 kev , together with an emission feature at 1.05 @xmath0 0.02 kev . this spectral shape is similar to that observed by asca during the spin - down phase , but significantly different from measurements during spin - up . this suggests that the change in spectrum observed by asca may be a stable feature during spin - down intervals . the source intensity is a factor @xmath12 lower than observed by asca three years earlier , confirming that continues to become fainter with time . . And you have already written the first three sentences of the full article: the x - ray source is a 7.7 s pulsar in a highly compact binary system of orbital period 2485 s. it is unusual in that it is one of the few low mass x - ray binary systems to contain an x - ray pulsar . while the x - ray emission is strongly modulated by the pulsar , there is no evidence for doppler shifts induced by the orbital motion of the source , despite extensive searches . the implies that the projected orbital radius of the neutron star is small , i.e. , @xmath2sin @xmath3 @xmath4 13 m - lt - s ( levine et al .. Please generate the next two sentences of the article

optical pulsations were first detected by ilovaisky et al . ( 1978 ) and interpreted as x - ray re - processing near to , or along , the line of sight to the x - ray source .

Suppose that you have an abstract for a scientific paper: we demonstrate the use of several code implementations of the mellin - barnes method available in the public domain to derive analytic expressions for the sunset diagrams that arise in the two - loop contribution to the pion mass and decay constant in three - flavoured chiral perturbation theory . we also provide results for all possible two - mass configurations of the sunset integral , and derive a new one - dimensional integral representation for the one mass sunset integral with arbitrary external momentum . thoroughly annotated mathematica notebooks are provided as ancillary files , which may serve as pedagogical supplements to the methods described in this paper . lu tp 16 - 43 + august 2016 * an analytic approach to sunset diagrams in chiral perturbation theory : theory and practice * + @xmath0 centre for high energy physics , indian institute of science , + bangalore-560012 , karnataka , india + @xmath1department of astronomy and theoretical physics , lund university , + slvegatan 14a , se 223 - 62 lund , sweden + @xmath2department of physics and astronomy , university of delaware , + newark , de 19716 , usa + . And you have already written the first three sentences of the full article: chiral perturbation theory is a low energy effective field theory of the strong interaction . the work @xcite presents analytic expressions for the two - loop contribution to the pion mass and decay constant in su(3 ) chiral perturbation theory with suitable expansions in powers of @xmath3 . in an upcoming work @xcite , we will present analogous expressions for the pion decay constant .. Please generate the next two sentences of the article

work is also underway to find similar simple analytic representations for the kaon and eta mass and decay constants to two loops . due to the goldstone nature of the particles involved , scalar , tensor and derivatives of sunset diagrams appear in these calculations , with various mass configurations and with up to three distinct masses .

Suppose that you have an abstract for a scientific paper: the change of the probability of proton emission in the nuclear photoeffect due to an intense coherent ( laser ) field is discussed near the threshold , where the hindering effect of the coulomb field of the remainder nucleus is essential . the ratio of the laser - assisted and laser - free differential cross section is deduced and found to be independent of the polarization state of the @xmath0 field and the two types of initial nuclear state considered . the numerical values of this ratio are given at some characteristic parameters of the intense field . . And you have already written the first three sentences of the full article: the development of coherent electromagnetic sources of higher and higher intensity with increasing photon energy up to the hard x - ray range motivates the theoretical study of the change of the processes of strongly bound systems , such as nuclear processes , by these intense fields ledingham . in this paper , the change of the nuclear photoeffect due to the presence of an intense coherent electromagnetic field is studied . this process is analogous to the laser - assisted x - ray photo effect ( x - ray absorption ) , a process which was already discussed @xcite in the late 80 s taking into account gauge invariance @xcite , @xcite . the laser - assisted nuclear photoeffect ( lanp ) and the laser - assisted x - ray photo effect ( x - ray absorption ) are laser - assisted bound - free transitions .. Please generate the next two sentences of the article

the difference between them lies in the charged particle ( proton or electron , respectively ) which takes part in these processes . although the lanp was recently investigated far from the threshold and neglecting the effect of the coulomb field of the remainder nucleus @xcite , in the case of the laser - assisted x - ray absorption processes it was found that the most interesting changes due to the presence of the laser field appear near the threshold @xcite , @xcite .

Suppose that you have an abstract for a scientific paper: the @xmath0 liouville theory has received some attention recently as the euclidean version of an exact rolling tachyon background . in an earlier paper it was shown that the bulk theory can be identified with the interacting @xmath0 limit of unitary minimal models . here we extend the analysis of the @xmath0-limit to the boundary problem . most importantly , we show that the fzzt branes of liouville theory give rise to a new 1-parameter family of boundary theories at @xmath0 . these models share many features with the boundary sine - gordon theory , in particular they possess an open string spectrum with band - gaps of finite width . we propose explicit formulas for the boundary 2-point function and for the bulk - boundary operator product expansion in the @xmath0 boundary liouville model . as a by - product of our analysis we also provide a nice geometric interpretation for zz branes and their relation with fzzt branes in the @xmath0 theory . . And you have already written the first three sentences of the full article: the study of tachyons and their condensation processes has been a longstanding challenge in string theory . during recent years , the interest in branes has added significantly to the relevance of this issue since open string tachyons occur in various configurations of stable branes , the most important being the brane - antibrane system . fortunately , unstable brane configurations turned out to be much more tractable than bulk backgrounds with instabilities such as e.g. the 26-dimensional bosonic string .. Please generate the next two sentences of the article

in fact , various different approaches have been employed over the last five years , including string field theory ( see e.g. @xcite and @xcite for a review ) , effective field theory models ( see @xcite for some early work ) , and world - sheet conformal field theory ( see e.g. @xcite and references therein ) . in @xcite , sen initiated the study of _ exact time - dependent solutions_. one goal of his work was to find a world - sheet description of so - called s - branes @xcite , i.e. of branes that are localized in time . in this context

Suppose that you have an abstract for a scientific paper: observational and theoretical evidence in support of metallicity dependent winds for wolf - rayet stars is considered . well known differences in wolf - rayet subtype distributions in the milky way , lmc and smc may be attributed to the sensitivity of subtypes to wind density . implications for wolf - rayet stars at low metallicity include a hardening of ionizing flux distributions , an increased wr population due to reduced optical line fluxes , plus support for the role of single wr stars as gamma ray burst progenitors . . And you have already written the first three sentences of the full article: wolf - rayet ( wr ) stars represent the final phase in the evolution of very massive stars prior to core - collapse , in which the h - rich envelope has been stripped away via either stellar winds or close binary evolution , revealing products of h - burning ( wn sequence ) or he - burning ( wc sequence ) at their surfaces , i.e. he , n or c , o ( crowther 2007 ) . wr stellar winds are significantly denser than o stars , as illustrated in fig . [ wrross ] , so their visual spectra are dominated by broad emission lines , notably heii @xmath04686 ( wn stars ) and ciii @xmath04647 - 51 , ciii @xmath05696 , civ @xmath05801 - 12 ( wc stars ) .. Please generate the next two sentences of the article

the spectroscopic signature of wr stars may be seen individually in local group galaxies ( e.g. massey & johnson 1998 ) , within knots in local star forming galaxies ( e.g. hadfield & crowther 2006 ) and in the average rest frame uv spectrum of lyman break galaxies ( shapley et al . 2003 ) . in the case of a single massive star , the strength of stellar winds during the main sequence and blue supergiant phase scales with the metallicity ( vink et al .

Suppose that you have an abstract for a scientific paper: we analyze the quantum walk on a cycle using discrete wigner functions as a way to represent the states and the evolution of the walker . the method provides some insight on the nature of the interference effects that make quantum and classical walks different . we also study the behavior of the system when the quantum coin carried by the walker interacts with an environment . we show that for this system quantum coherence is robust for initially delocalized states of the walker . the use of phase - space representation enables us to develop an intuitive description of the nature of the decoherence process in this system . . And you have already written the first three sentences of the full article: quantum walks @xcite have been proposed as potentially useful components of quantum algorithms @xcite . in recent years these systems have been studied in detail and some progress has been made in developing new quantum algorithms using either continuous @xcite or discrete @xcite versions of quantum walks . the key to the potential success of quantum walks seems to rely on the ability of the quantum walker to efficiently spread over a graph ( a network of sites ) in a way that is much faster than any algorithm based on classical coin tosses .. Please generate the next two sentences of the article

quantum interference plays an important role in quantum walks being the crucial ingredient enabling a faster than classical spread . for this reason , some effort was made in recent years in trying to understand the implications of the process of decoherence for quantum walks @xcite .

Suppose that you have an abstract for a scientific paper: we explore consequences of a radiation driven disk wind model for mass outflows from active galactic nuclei ( agn ) . we performed axisymmetric time - dependent hydrodynamic calculations using the same computational technique as proga , stone and kallman ( 2000 ) . we test the robustness of radiation launching and acceleration of the wind for relatively unfavorable conditions . in particular , we take into account the central engine radiation as a source of ionizing photons but neglect its contribution to the radiation force . additionally , we account for the attenuation of the x - ray radiation by computing the x - ray optical depth in the radial direction assuming that only electron scattering contributes to the opacity . our new simulations confirm the main result from our previous work : the disk atmosphere can shield itself from external x - rays so that the local disk radiation can launch gas off the disk photosphere . we also find that the local disk force suffices to accelerate the disk wind to high velocities in the radial direction . this is true provided the wind does not change significantly the geometry of the disk radiation by continuum scattering and absorption processes ; we discuss plausibility of this requirement . synthetic profiles of a typical resonance ultraviolet line predicted by our models are consistent with observations of broad absorption line ( bal ) qsos . . And you have already written the first three sentences of the full article: radiation pressure on spectral lines ( line force ) driving a wind from an accretion disk is the most promising hydrodynamical ( hd ) scenario for agn outflows . within this framework , a wind is launched from the disk by the local disk radiation at radii where the disk radiation is mostly in the ultraviolet ( uv ; e.g. , shlosman , vitello & shaviv 1985 ; murray et al . 1995 , mcgv hereafter ) .. Please generate the next two sentences of the article

such a wind is continuous and has mass loss rate and velocity which are are capable of explaining the blueshifted absorption lines observed from many agn , if the ionization state is suitable . such winds have the desirable feature that they do not rely on unobservable forces or fields for their motive power . however , detailed tests of this idea via modelling is challenging .

Suppose that you have an abstract for a scientific paper: we study the hyperbolicity of a class of horseshoes exhibiting an _ internal _ tangency , i.e. a point of homoclinic tangency accumulated by periodic points . in particular these systems are strictly _ not _ uniformly hyperbolic . however we show that all the lyapunov exponents of all invariant measures are uniformly bounded away from 0 . this is the first known example of this kind . . And you have already written the first three sentences of the full article: we consider @xmath0 diffeomorphisms on riemannian surfaces . our goal is to study the hyperbolic properties of a class of maps exhibiting a homoclinic tangency associated to a fixed saddle point @xmath1 , as in figure [ map ] . homoclinic tangencies inside the limit set , width=226 ] we assume without loss of generality that we are working on @xmath2 and in the standard euclidean norm . we recall that a compact invariant set @xmath3 is * uniformly hyperbolic * if there exist constants @xmath4 and a continuous , @xmath5-invariant , decomposition @xmath6 of the tangent bundle over @xmath7 such that for all @xmath8 and all @xmath9 we have @xmath10 by standard hyperbolic theory , every point @xmath11 in @xmath7 has stable and unstable manifolds @xmath12 tangent to the subspaces @xmath13 and @xmath14 respectively , and thus in particular _ transversal _ to each other .. Please generate the next two sentences of the article

the presence of the tangency therefore implies that the dynamics on @xmath15 can not be uniformly hyperbolic . we emphasize at this point that , in the case we are considering , the homoclinic tangency is accumulated by transverse homoclinic orbits which in turn are accumulated by periodic points .

Suppose that you have an abstract for a scientific paper: based on 3d hydrodynamical model atmospheres computed with the co@xmath0bold code and 3d non - lte ( nlte ) line formation calculations , we study the effect of the convection - induced line asymmetry on the derived @xmath1li abundance for a range in effective temperature , gravity , and metallicity covering the stars of the ( * ? ? ? * asplund ( 2006 ) ) sample . when the asymmetry effect is taken into account for this sample of stars , the resulting @xmath1li/@xmath2li ratios are reduced by about 1.5% on average with respect to the isotopic ratios determined by ( * ? ? ? * asplund ( 2006 ) ) . this purely theoretical correction diminishes the number of significant @xmath1li detections from 9 to 4 ( 2@xmath3 criterion ) , or from 5 to 2 ( 3@xmath3 criterion ) . in view of this result the existence of a @xmath1li plateau appears questionable . a careful reanalysis of individual objects by fitting the observed lithium @xmath4 doublet both with 3d nlte and 1d lte synthetic line profiles confirms that the inferred @xmath1li abundance is systematically lower when using 3d nlte instead of 1d lte line fitting . nevertheless , halo stars with unquestionable @xmath1li detection do exist even if analyzed in 3d - nlte , the most prominent example being hd84937 . . And you have already written the first three sentences of the full article: the spectroscopic signature of the presence of @xmath1li in the atmospheres of metal - poor halo stars is a subtle extra depression in the red wing of the @xmath2li doublet , which can only be detected in spectra of the highest quality . based on high - resolution , high signal - to - noise vlt / uves spectra of 24 bright metal - poor stars , ( * ? ? ? * asplund ( 2006 ) ) report the detection of @xmath1li in nine of these objects .. Please generate the next two sentences of the article

the average @xmath1li/@xmath2li isotopic ratio in the nine stars in which @xmath1li has been detected is about 4% and is very similar in each of these stars , defining a @xmath1li plateau at approximately @xmath5li@xmath6 ( on the scale @xmath7h@xmath8 ) . a convincing theoretical explanation of this new @xmath1li plateau turned out to be problematic : the high abundances of @xmath1li at the lowest metallicities can not be explained by current models of galactic cosmic - ray production , even if the depletion of @xmath1li during the pre - main - sequence phase is ignored ( see reviews by e.g. ( * ? ? ?

Suppose that you have an abstract for a scientific paper: the smallest polyatomic carbon chain , c@xmath0 , has been identified in interstellar clouds ( a@xmath11 mag ) towards @xmath2 ophiuchi , 20 aquilae , and @xmath2 persei by detection of the origin band in its @xmath3 electronic transition , near 4052 . individual rotational lines were resolved up to @xmath4=30 enabling the rotational level column densities and temperature distributions to be determined . the inferred limits for the total column densities ( @xmath51 to 2@xmath6 @xmath7 ) offer a strong incentive to laboratory and astrophysical searches for the longer carbon chains . concurrent searches for c@xmath8 , c@xmath9 and c@xmath10 were negative but provide sensitive estimates for their maximum column densities . . And you have already written the first three sentences of the full article: carbon chains play a central role in the chemistry and spectroscopy of interstellar space . the detection of cyanopolyacetylenes in dense interstellar clouds @xcite led to the suggestion by @xcite that carbon chain species be considered as candidates for the diffuse interstellar bands ( dibs ) , which are found in the 4000 - 8500 spectral region of stars reddened by interstellar dust @xcite . since then , many other molecules with a carbon chain backbone have been identified at radio frequencies in dense clouds @xcite .. Please generate the next two sentences of the article

meanwhile , advances in laboratory measurements have provided an understanding of the types and sizes of carbon chains which have strong electronic transitions in the dib range @xcite . it is thus somewhat surprising that as yet among the bare carbon species only diatomic c@xmath11 has been identified in interstellar clouds where dib are detected .

Suppose that you have an abstract for a scientific paper: we present an investigation for the generation of intense magnetic fields in dense plasmas with an anisotropic electron fermi - dirac distribution . for this purpose , we use a new linear dispersion relation for transverse waves in the wigner - maxwell dense quantum plasma system . numerical analysis of the dispersion relation reveals the scaling of the growth rate as a function of the fermi energy and the temperature anisotropy . the nonlinear saturation level of the magnetic fields is found through fully kinetic simulations , which indicates that the final amplitudes of the magnetic fields are proportional to the linear growth rate of the instability . the present results are important for understanding the origin of intense magnetic fields in dense fermionic plasmas , such as those in the next generation intense laser - solid density plasma experiments . . And you have already written the first three sentences of the full article: the existence of feeble magnetic fields of several microgauss in our galaxies @xcite , as well as of gigagauss in intense laser - plasma interaction experiments @xcite and of billions of gauss in compact astrophysical objects @xcite ( e.g. super dense white dwarfs , neutron stars / magnetars , degenerate stars , supernovae ) is well known . the generation mechanisms for seed magnetic fields in cosmic / astrophysical environments are still debated , while the spontaneous generation of magnetic fields in laser - produced plasmas is attributed to the biermann battery @xcite ( also referred to as the baroclinic vector containing non - parallel electron density and electron temperature gradients ) and to the return electron current from the solid target . computer simulations of laser - fusion plasmas have shown evidence of localized anisotropic electron heating by resonant absorption , which in turn can drive a weibel - like instability resulting in megagauss magnetic fields @xcite .. Please generate the next two sentences of the article

there have also been observations of the weibel instability in high intensity laser - solid interaction experiments @xcite . furthermore , a purely growing weibel instability @xcite , arising from the electron temperature anisotropy ( a bi - maxwellian electron distribution function ) is also capable of generating magnetic fields and associated shocks @xcite .

Suppose that you have an abstract for a scientific paper: we present a novel method for reconstructing the shape of an object from measured gradient data . a certain class of optical sensors does not measure the shape of an object , but its local slope . these sensors display several advantages , including high information efficiency , sensitivity , and robustness . for many applications , however , it is necessary to acquire the shape , which must be calculated from the slopes by numerical integration . existing integration techniques show drawbacks that render them unusable in many cases . our method is based on approximation employing radial basis functions . it can be applied to irregularly sampled , noisy , and incomplete data , and it reconstructs surfaces both locally and globally with high accuracy . . And you have already written the first three sentences of the full article: in industrial inspection , there is an ever - growing demand for highly accurate , non - destructive measurements of three - dimensional object geometries . a variety of optical sensors have been developed to meet these demands @xcite . these sensors satisfy the requirements at least partially .. Please generate the next two sentences of the article

numerous applications , however , still wait for a capable metrology . the limitations of those sensors emerge from physics and technology the physical limits are determined by the wave equation and by coherent noise , while the technological limits are mainly due to the space - time - bandwidth product of electronic cameras .

Suppose that you have an abstract for a scientific paper: we study the landau gauge gluon propagator at zero and finite temperature using lattice simulations . particular attention is given to the finite size effects and to the infrared behaviour . . And you have already written the first three sentences of the full article: in lattice qcd , the finite lattice spacing and finite lattice volume effects on the gluon propagator can be investigated with the help of lattice simulations at several lattice spacings and physical volumes . here we report on such a calculation . for details on the lattice setup see @xcite . in figure. Please generate the next two sentences of the article

[ fig : gluevol ] , we show the renormalized gluon propagator at @xmath0 gev for all lattice simulations . note that we compare our data with the large volume simulations performed by the berlin - moscow - adelaide collaboration @xcite see @xcite for details . in each plot

Suppose that you have an abstract for a scientific paper: assume that we are given a closed chord - generic legendrian submanifold @xmath0 of the contactisation of a liouville manifold , where @xmath1 moreover admits an exact lagrangian filling @xmath2 inside the symplectisation . under the further assumptions that this filling is spin and has vanishing maslov class , we prove that the number of reeb chords on @xmath1 is bounded from below by the stable morse number of @xmath3 . given a general exact lagrangian filling @xmath3 , we show that the number of reeb chords is bounded from below by a quantity depending on the homotopy type of @xmath3 , following ono - pajitnov s implementation in floer homology of invariants due to sharko . this improves previously known bounds in terms of the betti numbers of either @xmath1 or @xmath3 . . And you have already written the first three sentences of the full article: one of the first striking applications of gromov s theory of pseudoholomorphic curves @xcite was that a closed exact lagrangian immersion @xmath4 inside a liouville manifold must have a double - point , given the assumption that it is hamiltonian displaceable . gromov s result has the following contact - geometric reformulation , which will turn out to be useful . consider the so - called _ contactisation _ @xmath5 of the liouville manifold @xmath6 , which is a contact manifold with the choice of a contact form . recall that a ( generic ) exact lagrangian immersion @xmath4 lifts to a legendrian ( embedding ) @xmath7 .. Please generate the next two sentences of the article

one says that @xmath1 is _ horizontally displaceable _ given that @xmath8 is hamiltonian displaceable . the above result thus translates into the fact that a horizontally displaceable legendrian submanifold @xmath1 must have a _

Suppose that you have an abstract for a scientific paper: we study the effects of chromoelectric and chromomagnetic dipole moments ( cedm and cmdm ) on the production cross section of single top @xmath0-channel at the lhc based on the effective lagrangian approach . we show that the impact of cedm and cmdm could be large . using the experimental measurement of the @xmath0-channel cross section , constraints on cedm and cmdm are extracted . these constraints are comparable with the ones obtained from the top pair analysis . 0.65 cm 0.5 cm * seyed yaser ayazi , hoda hesari and mojtaba mohammadi najafabadi*0.5 cm school of particles and accelerators , institute for research in fundamental sciences ( ipm ) , p.o . box 19395 - 5531 , tehran , iran . And you have already written the first three sentences of the full article: the top quark is the heaviest standard model ( sm ) particle which has been discovered so far , and might be the first place in which new physics effects could appear . while the top quark has been discovered and studied in some details at the tevatron , many of its properties are being studied at the lhc with high precision . since new physics can show up in the couplings of the top quark with other sm particles , in particular gauge bosons , the precise measurement of the top couplings among the top quark and gauge bosons is important . in particular ,. Please generate the next two sentences of the article

the top quark is copiously produced at the lhc , the lhc experiments are the places to probe these couplings@xcite . at the lhc , top quarks are produced primarily via two independent mechanisms .

Suppose that you have an abstract for a scientific paper: we introduce four basic two - dimensional ( 2d ) plaquette configurations with onsite cubic nonlinearities , which may be used as building blocks for 2d @xmath0-symmetric lattices . for each configuration , we develop a dynamical model and examine its @xmath1symmetry . the corresponding nonlinear modes are analyzed starting from the hamiltonian limit , with zero value of the gain - loss coefficient , @xmath2 . once the relevant waveforms have been identified ( chiefly , in an analytical form ) , their stability is examined by means of linearization in the vicinity of stationary points . this reveals diverse and , occasionally , fairly complex bifurcations . the evolution of unstable modes is explored by means of direct simulations . in particular , stable localized modes are found in these systems , although the majority of identified solutions is unstable . . And you have already written the first three sentences of the full article: the theme of @xmath0 ( parity time ) symmetric systems was initiated in the works of bender and collaborators @xcite as an alternative to the standard quantum theory , where the hamiltonian is postulated to be hermitian . the principal conclusion of these works was that @xmath0-invariant hamiltonians , which are not necessarily hermitian , may still give rise to completely real spectra , thus being appropriate for the description of physical settings . in terms of the schrdinger - type hamiltonians , which include the usual kinetic - energy operator and the potential term , @xmath3 , the @xmath0-invariance admits complex potentials , subject to constraint that @xmath4 .. Please generate the next two sentences of the article

recent developments in optics have resulted in an experimental realization of the originally theoretical concept of the @xmath0-symmetric hamiltonians , chiefly due to the work by christodoulides and co - workers christo1 ( see also @xcite ) . it has been demonstrated that the controllable imposition of symmetrically set and globally balanced gain and loss may render optical waveguiding arrays a fertile territory for the construction of @xmath0-symmetric complex potentials .

Suppose that you have an abstract for a scientific paper: this paper presents a low - ml - decoding - complexity , full - rate , full - diversity space - time block code ( stbc ) for a @xmath0 transmit antenna , @xmath0 receive antenna multiple - input multiple - output ( mimo ) system , with coding gain equal to that of the best and well known golden code for any qam constellation . recently , two codes have been proposed ( by paredes , gershman and alkhansari and by sezginer and sari ) , which enjoy a lower decoding complexity relative to the golden code , but have lesser coding gain . the @xmath1 stbc presented in this paper has lesser decoding complexity for non - square qam constellations , compared with that of the golden code , while having the same decoding complexity for square qam constellations . compared with the paredes - gershman - alkhansari and sezginer - sari codes , the proposed code has the same decoding complexity for non - rectangular qam constellations . simulation results , which compare the codeword error rate ( cer ) performance , are presented . . And you have already written the first three sentences of the full article: multiple - input , multiple - output(mimo ) wireless transmission systems have been intensively studied during the last decade . the alamouti code @xcite for two transmit antennas is a novel scheme for mimo transmission , which , due to its orthogonality properties , allows a low complexity maximum - likelihood ( ml ) decoder . this scheme led to the generalization of stbcs from orthogonal designs @xcite .. Please generate the next two sentences of the article

such codes allow the transmitted symbols to be decoupled from one another and single - symbol ml decoding is achieved over _ quasi static _ rayleigh fading channels . even though these codes achieve the maximum diversity gain for a given number of transmit and receive antennas and for any arbitrary complex constellations , unfortunately , these codes are not @xmath2 , where , by a @xmath2 code , we mean a code that transmits at a rate of @xmath3 complex symbols per channel use for an @xmath4 transmit antenna , @xmath5 receive antenna system . the golden code @xcite is a full - rate , full - diversity code and has a decoding complexity of the order of @xmath6 for arbitrary constellations of size @xmath7 the codes in @xcite and the trace - orthogonal cyclotomic code in @xcite also match the golden code . with reduction in the decoding complexity

Suppose that you have an abstract for a scientific paper: we analyse the mass matrix of the three light neutrinos in the basis where the charged - lepton mass matrix is diagonal and discuss constraints on its elements for the majorana and the dirac case . . And you have already written the first three sentences of the full article: the recent enormous improvement of our knowledge of the neutrino oscillation parameters suggests a detailed investigation of the current constraints on the neutrino mass matrix . most of these constraints depend on the assumed nature of neutrinos ( dirac or majorana ) . the structure of this paper is as follows . after a brief general discussion of the light - neutrino mass matrix in section [ section - neutrino_mass_matrix ]. Please generate the next two sentences of the article

, we will investigate the implications of the currently available data on the majorana neutrino mass matrix in section [ section - majorana ] . in section [ section - dirac ] we will discuss constraints on the neutrino mass matrix in the dirac case .

Suppose that you have an abstract for a scientific paper: we present the results of a joint investigation aimed at constraining the primordial he content ( @xmath0 ) on the basis of both the cosmic microwave background ( cmb ) anisotropy and two stellar observables , namely the tip of the red giant branch ( trgb ) and the luminosity of the zero age horizontal branch ( zahb ) . current baryon density estimates based on cmb measurements cover a wide range values @xmath1 , that according to big bang nucleosynthesis ( bbn ) models would imply @xmath2 . we constructed several sets of evolutionary tracks and hb models by adopting @xmath3 and several metal contents . the comparison between theory and observations suggests that zahb magnitudes based on he - enhanced models are 1.5@xmath4 brighter than the empirical ones . the same outcome applies for the trgb bolometric magnitudes . this finding somewhat supports a @xmath0 abundance close to the canonical 0.23 - 0.24 value . more quantitative constraints on this parameter are hampered by the fact that the cmb pattern shows a sizable dependence on both @xmath0 and the baryon density only at small angular scales , i.e. at high @xmath5 in the power spectrum ( @xmath6 ) . however , this region of the power spectrum could be still affected by deceptive systematic uncertainties . finally , we suggest to use the _ uv - upturn _ to estimate the he content on gpc scales . in fact , we find that a strong increase in @xmath0 causes in metal - poor , hot hb structures a decrease in the uv emission . . And you have already written the first three sentences of the full article: the comparison between chemical abundances of deuterium , helium , and lithium predicted by bbn models with current empirical estimates is one of the most viable method to constrain the physical mechanisms and the cosmology which governed the nucleosynthesis of primordial abundances ( olive , steigman , & walker 2000 ) . as far as the primordial he content is concerned , current empirical estimates are mainly based on measurements of nebular emission lines in low - metallicity , extragalactic hii regions ( izotov , thuan , & lipovetsky 1997 ; olive , steigman , & skillman 1997 ) . recent he determinations present small observational errors ( @xmath7% ) , but large uncertainties between independent measurements : @xmath8 by olive & steigman ( 1995 ) against @xmath9 by izotov & thuan ( 1998 ) .. Please generate the next two sentences of the article

this evidence suggests that current he abundances are still dominated by systematic errors . in fact , viegas , gruenwald , & steigman ( 2000 ) and gruenwald , steigman , & viegas ( 2001 ) in two detailed investigations on the ionization correction for unseen neutral and doubly - ionized he in hii regions , found that he estimates should be reduced by 0.006 ( @xmath10 ) , a quantity which is a factor of 2 - 3 larger than typical statistical errors quoted in the literature . moreover and even more importantly , pistinner et al .

Suppose that you have an abstract for a scientific paper: we study diffusive electron - electron interaction correction to conductivity by analyzing simultaneously @xmath0 and @xmath1 for disordered 2d electron systems in si in tilted magnetic field . tilting the field is shown to be a straightforward tool to disentangle spin and orbital effects . in particular , by changing the tilt angle we prove experimentally that in the field range @xmath2 the correction depends on modulus of magnetic field rather than on its direction , which is expected for a system with isotropic @xmath3-factor . in the high - field limit the correction behaves as @xmath4 , as expected theoretically ( lee , ramakrishnan , phys . rev . b*26 * , 4009 ( 1982 ) ) . our data prove that the diffusive electron - electron interaction correction to conductivity is not solely responsible for the huge and temperature dependent magnetoresistance in parallel field , typically observed in si - mosfets . . And you have already written the first three sentences of the full article: a diffusive electron - electron interaction correction ( eec ) to the conductivity was predicted theoretically @xcite about 30 years ago . in 2d system it is proportional to @xmath5 ( @xmath6 is the momentum relaxation time ) and grows in amplitude as temperature decreases . a way to experimentally single - out eec among other numerous effects is based on its property not to affect hall component of magnetoconductivity tensor @xmath7 in perpendicular magnetic field @xcite .. Please generate the next two sentences of the article

eec therefore gives birth to temperature - dependent and parabolic with field contribution to the diagonal magnetoresistance @xmath8 and correction to the hall coefficient @xmath9 , both being proportional to @xmath5 . the predicted features were observed in numerous experiments , mainly with n - type gaas - based 2d systems @xcite .

Suppose that you have an abstract for a scientific paper: in this paper we study the flat ( @xmath0 ) cosmological frw model with holonomy corrections of loop quantum gravity . the considered universe contains a massless scalar field and the cosmological constant @xmath1 . we find analytical solutions for this model in different configurations and investigate its dynamical behaviour in the whole phase space . we show the explicit influence of @xmath1 on the qualitative and quantitative character of solutions . even in the case of positive @xmath1 the oscillating solutions without the initial and final singularity appear as a generic case for some quantisation schemes . . And you have already written the first three sentences of the full article: in recent years loop quantum cosmology ( lqc ) has inspired realisation of the cosmological scenario in which the initial singularity is replaced by the bounce . in this picture , the universe is initially in the contracting phase , reaches the minimal , nonzero volume and , thanks to quantum repulsion , evolves toward the expanding phase . such a scenario has been extensively studied with use of the numerical methods @xcite . however , as it was shown for example in @xcite exact solutions for bouncing universe with dust and cosmological constant can be found . the aim of the present paper is to show that analytical solutions can also be obtained for the bouncing models arising from lqc .. Please generate the next two sentences of the article

the main advantage of such exact solutions is that they allow for investigations in whole ranges of the parameter domains . in this paper we consider the flat frw model with a free scalar field and with the cosmological constant .

Suppose that you have an abstract for a scientific paper: we discuss the physical interpretation of a dynamical and inhomogeneous spherically symmetric solution obtained by fonarev for a scalar field with an exponential potential . there is a single parameter @xmath0 in the solution which can be set to @xmath1 if it is non - zero , in addition to the steepness parameter @xmath2 in the potential . the spacetime is conformally static and asymptotically flat friedmann - robertson - walker spacetime . the solution reduces to the friedmann - robertson - walker solution for @xmath3 . there are two curvature singularities , of which one is a timelike central singularity and the other is a big - bang or big - crunch type singularity . depending on the parameters , the spacetime can possess a future outer trapping horizon in the collapsing case . then the solution represents a dynamical black hole in the sense of hayward although there is a locally naked singularity at the center and no black - hole event horizon . this demonstrates a weak point of the local definition of a black hole in terms of a trapping horizon . einstein equations are so complicated simultaneous nonlinear partial differential equations that it is hopeless to obtain general solutions . thus , spacetime symmetries are often assumed to make the system more tractable . although such spacetimes with high symmetries are idealized ones , they have occupied an important position in the history of gravitation research as touchstones to know the essential physics @xcite . for example , the friedmann - robertson - walker ( frw ) cosmological model plays a central role in modern cosmology as the zeroth - order approximation of the present universe , on which the behavior of the density perturbations has been particularly investigated to clarify the origin of the large - scale structure of the universe or to determine the cosmological parameters from the observations of the cosmic microwave background @xcite . from the analyses of the stationary and asymptotically flat black - hole.... And you have already written the first three sentences of the full article: the author would like to thank c. bunster , c. martnez , r. troncoso , s. willison , and j. zanelli for useful comments . the author thanks kjell tangen for the crucial information of the paper by fonarev . this work was supported by the grant nos .. Please generate the next two sentences of the article

1071125 from fondecyt ( chile ) and the grant - in - aid for scientific research fund of the ministry of education , culture , sports , science and technology , japan ( young scientists ( b ) 18740162 ) . 99 h. stephani , d. kramer , m. maccullum , c. hoenselaers and e. herlt , _ exact solutions of einsteins field equations : second edition _ , ( cambridge university press , cambridge , 2003 ) .

Suppose that you have an abstract for a scientific paper: cataclysmic variables ( cvs ) are binaries in which a compact white dwarf accretes material from a low - mass companion star . the discovery of two planets in orbit around the cv hu aquarii opens unusual opportunities for understanding the formation and evolution of this system . in particular the orbital parameters of the planets constrains the past and enables us to reconstruct the evolution of the system through the common - envelope phase . during this dramatic event the entire hydrogen envelope of the primary star is ejected , passing the two planets on the way . the observed eccentricities and orbital separations of the planets in hu aqr enable us to limit the common - envelope parameter @xmath0 or @xmath1 and measure the rate at which the common envelope is ejected , which turns out to be copious . the mass in the common envelope is ejected from the binary system at a rate of @xmath2 . the reconstruction of the initial conditions for hu aqr indicates that the primary star had a mass of @xmath3 and a @xmath4 companion in a @xmath5160 ( best value @xmath6 ) binary . the two planets were born with an orbital separation of @xmath7 and @xmath8 respectively . after the common envelope , the primary star turns into a @xmath9 helium white dwarf , which subsequently accreted @xmath10 from its roche - lobe filling companion star , grinding it down to its current observed mass of @xmath11 . methods : numerical planets and satellites : dynamical evolution and stability planet star interactions planets and satellites : formation stars : individual : hu aquarius stars : binaries : evolution . And you have already written the first three sentences of the full article: the cataclysmic variable hu aqr currently consists of a 0.80 white dwarf that accretes from a 0.18 main - sequence companion star . the transfer of mass in the tight @xmath12 orbit is mediate by the emission of gravitational waves and the strong magnetic field of the accreting star . since its discovery , irregularities of the observed - calculated variations have led to a range of explanations , including the presence of circum - binary planets .. Please generate the next two sentences of the article

detailed timing analysis has eventually led to the conclusion that the cv is orbited by two planets @xcite , a 5.7 planet in a @xmath13 orbit with an eccentricity of @xmath14 and a somewhat more massive ( 7.6 ) planet in a wider @xmath15 and eccentric @xmath16 orbit @xcite . although , the two - planet configuration turned out to be dynamically unstable on a 100010,000 year time scale ( * ? ? ? * see also [ sect : stability ] ) , a small fraction of the numerical simulations exhibit long term dynamical stability ( for model b2 in * ? ? ?

Suppose that you have an abstract for a scientific paper: we introduce an extension of the @xmath0 no - core shell model / resonating group method ( ncsm / rgm ) in order to describe three - body cluster states . we present results for the @xmath1he ground state within a @xmath2he+n+n cluster basis as well as first results for the phase shifts of different channels of the @xmath2he+n+n system which provide information about low - lying resonances of this nucleus . example.eps gsave newpath 20 20 moveto 20 220 lineto 220 220 lineto 220 20 lineto closepath 2 setlinewidth gsave .4 setgray fill grestore stroke grestore . And you have already written the first three sentences of the full article: the @xmath0 ncsm / rgm was presented in @xcite as a promising technique that is able to treat both structure and reactions in light nuclear systems . this approach combines a microscopic cluster technique with the use of realistic interactions and a consistent @xmath0 description of the nucleon clusters . the method has been introduced in detail for two - body cluster bases and has been shown to work efficiently in different systems @xcite .. Please generate the next two sentences of the article

however , there are many interesting systems that have a three - body cluster structure and therefore can not be successfully studied with a two - body cluster approach . the extension of the ncsm / rgm approach to properly describe three - body cluster states is essential for the study of nuclear systems that present such configuration .

Suppose that you have an abstract for a scientific paper: we have modeled a large sample of infrared starburst galaxies using both the pegase v2.0 and starburst99 codes to generate the spectral energy distribution ( sed ) of the young star clusters . pegase utilizes the padova group tracks while starburst99 uses the geneva group tracks , allowing comparison between the two . we used our mappings iii code to compute photoionization models which include a self - consistent treatment of dust physics and chemical depletion . we use the standard optical diagnostic diagrams as indicators of the hardness of the euv radiation field in these galaxies . these diagnostic diagrams are most sensitive to the spectral index of the ionizing radiation field in the 1 - 4 rydberg region . we find that warm infrared starburst galaxies contain a relatively hard euv field in this region . the pegase ionizing stellar continuum is harder in the 1 - 4 rydberg range than that of starburst99 . as the spectrum in this regime is dominated by emission from wolf - rayet ( w - r ) stars , this difference is most likely due to the differences in stellar atmosphere models used for the w - r stars . the pegase models use the @xcite planetary nebula nuclei ( pnn ) atmosphere models for the wolf - rayet stars whereas the starburst99 models use the @xcite wolf - rayet atmosphere models . we believe that the @xcite atmospheres are more applicable to the starburst galaxies in our sample , however they do not produce the hard euv field in the 1 - 4 rydberg region required by our observations . the inclusion of continuum metal blanketing in the models may be one solution . supernova remnant ( snr ) shock modeling shows that the contribution by mechanical energy from snrs to the photoionization models is @xmath0% . the models presented here are used to derive a new theoretical classification scheme for starbursts and agn galaxies based on the optical diagnostic diagrams . . And you have already written the first three sentences of the full article: observations of starburst galaxies can provide vital insights into the processes and spectral characteristics of massive star formation regions . in such regions the physical conditions are similar to those that existed at the time of collapse and formation of galaxies in the early universe , and they can also provide an understanding of early galaxy evolution . the _ infrared astronomical satellite _ ( iras ) made the key discovery of large numbers of infrared luminous galaxies , similar to those found by @xcite .. Please generate the next two sentences of the article

many of these are dominated by intense star formation @xcite in which the luminosity of the young hot stars heats the surrounding dust , producing large amounts of infrared radiation . the theoretical tools required to interpret the spectra of such galaxies are now available . for example , detailed stellar population synthesis models have been developed for both instantaneous and continuous starbursts and using these models , one is able to derive parameters such as the starburst age and metallicity from the continuous spectrum . in such models , the stellar initial mass function ( imf ) , star formation rate ( sfr ) and stellar atmosphere formulations are all adjustable initial parameters .

Suppose that you have an abstract for a scientific paper: the usefulness of the @xmath0 decay chain is investigated for the @xmath1-reconstruction in the future atlas @xmath1-mixing experiment . it is shown that this decay channel is almost as suitable for this purpose as previously studied @xmath2 . -10 mm . And you have already written the first three sentences of the full article: in the standard model @xmath3 and @xmath4 are not mass eigenstates . instead we have ( the small cp - violating effects are neglected ) @xmath5 so the time evolution of the @xmath6 states looks like @xmath7 where @xmath8 is the mass eigenvalue and @xmath9 - the corresponding width . it follows from ( 1 ) and ( 2 ) that the probability for @xmath3 meson not to change its flavour after a time @xmath10 from the creation is @xmath11 and the probability to convert into the @xmath4 meson . Please generate the next two sentences of the article

@xmath12where @xmath13 is the average width and @xmath14 . so @xmath15 mass difference between the @xmath16 mass eigenstates defines the oscillation frequency .

Suppose that you have an abstract for a scientific paper: a lead scintillator sandwich sampling calorimeter has been installed in the hera tunnel 105.6 m from the central zeus detector in the proton beam direction . it is designed to measure the energy and scattering angle of neutrons produced in charge exchange @xmath0 collisions . before installation the calorimeter was tested and calibrated in the h6 beam at cern where 120 gev electrons , muons , pions and protons were made incident on the calorimeter . in addition , the spectrum of fast neutrons from charge exchange proton - lucite collisions was measured . the design and construction of the calorimeter is described , and the results of the cern test reported . special attention is paid to the measurement of shower position , shower width , and the separation of electromagnetic showers from hadronic showers . the overall energy scale as determined from the energy spectrum of charge exchange neutrons is compared to that obtained from direct beam hadrons . hep - ex/9701015 + desy 97 - 006 + design and test of a + forward neutron calorimeter + for the zeus experiment + the zeus fnc group + s. bhadra@xmath1 , i. bohnet@xmath2 , m. cardy@xmath1 , u. dosselli@xmath3 , c .- p . fagerstroem@xmath1 , w. frisken@xmath1 , k. furutani@xmath1 , d. hanna@xmath4 , u. holm@xmath2 , k. f. johnson@xmath5 , m. khakzad@xmath1 , g. levman@xmath6 , j. n. lim@xmath4 , b. loehr@xmath7 , j. f. martin@xmath6 , c. muhl@xmath7 , t. neumann@xmath2 , m. rohde@xmath7 , w. b. schmidke@xmath1 , d. g. stairs@xmath4 , h. tiecke@xmath8 , c. voci@xmath3 + [ cols= " > , < " , ] the photomultipliers were read out with lecroy 4300 charge integrating adcs . the adcs were gated so that 160 ns of the pulse from the calorimeter was integrated . during data taking the adc pedestals were regularly measured , and the gains were monitored with an internal test function in the units . the gains were also checked daily using an external charge injector . over the course of the beam test , which.... And you have already written the first three sentences of the full article: since the spring of 1995 , the fnc has been operating in the zeus experiment at hera where it is used in the study of leading neutrons produced at small angles with energies @xmath92 100 gev . because the calorimeter has been calibrated and tested only in beams of energy up to 120 gev , and because the top was not present for the beam tests , we must rely on a monte carlo simulation to predict the response of the calorimeter to high energy particles . we have modeled the fnc using the geant 3.13@xcite program , upon which the simulation of the full zeus detector is based . in this section we present some results from the simulation which can be compared to our test beam data . for 120 gev electrons and pions incident on the center of towers 5 and 6. Please generate the next two sentences of the article

the geant simulation predicts an electron to hadron response ratio of 0.98 , in agreement with the measured value of 0.96 . the simulated response to pions incident on the center of each tower is shown in fig .

Suppose that you have an abstract for a scientific paper: we present single - dish h spectra obtained with the green bank telescope , along with optical photometric properties from the sloan digital sky survey , of 20 nearby ( d @xmath0 70 mpc ) luminous compact blue galaxies ( lcbgs ) . these @xmath1l@xmath2 , blue , high surface brightness , starbursting galaxies were selected with the same criteria used to define lcbgs at higher redshifts . we find these galaxies are gas - rich , with m@xmath3 ranging from 5@xmath410@xmath5 to 8@xmath410@xmath6 m@xmath7 , and m@xmath3 l@xmath8 ranging from 0.2 to 2 m@xmath7 l@xmath9 , consistent with a variety of morphological types of galaxies . we find the dynamical masses ( measured within r@xmath10 ) span a wide range , from 3@xmath410@xmath6 to 1@xmath410@xmath11 m@xmath7 . however , at least half have dynamical mass - to - light ratios smaller than nearby galaxies of all hubble types , as found for lcbgs at intermediate redshifts . by comparing line widths and effective radii with local galaxy populations , we find that lcbgs are consistent with the dynamical mass properties of magellanic ( low luminosity ) spirals , and the more massive irregulars and dwarf ellipticals , such as ngc 205 . . And you have already written the first three sentences of the full article: the hubble space telescope and advances in ground based observing have greatly increased our knowledge of the galaxy population in the distant universe . however , the nature of these galaxies and their evolutionary connections to local galaxies remain poorly understood . luminous , compact , star forming galaxies appear to represent a prominent phase in the early history of galaxy formation @xcite . in particular : * the number density of luminous , compact star forming galaxies rises significantly out to z @xmath1 1 @xcite . * the lyman break galaxies at z @xmath12 2 seen in the hubble deep field are characterized by very compact cores and a high surface brightness @xcite . *. Please generate the next two sentences of the article

sub - millimeter imaging has revealed distant galaxies ( z @xmath1 2@xmath134 ) , half of them compact objects , which may be responsible for as much as half of the total star formation rate in the early universe @xcite . however , little is definitively known of their physical properties , or how they are related to subsets of the local galaxy population . a classification for known examples of intermediate redshift ( 0.4 @xmath0 z @xmath0 0.7 ) luminous , blue , compact galaxies , such as blue nucleated galaxies , compact narrow emission line galaxies , and small blue galaxies , has been developed by @xcite in order to be able to choose samples over a wide redshift range .

Suppose that you have an abstract for a scientific paper: period - colour ( pc ) and amplitude - colour ( ac ) relations are studied for the large magellanic cloud ( lmc ) cepheids under the theoretical framework of the hydrogen ionization front ( hif ) - photosphere interaction . lmc models are constructed with pulsation codes that include turbulent convection , and the properties of these models are studied at maximum , mean and minimum light . as with galactic models , at maximum light the photosphere is located next to the hif for the lmc models . however very different behavior is found at minimum light . the long period ( @xmath0days ) lmc models imply that the photosphere is disengaged from the hif at minimum light , similar to the galactic models , but there are some indications that the photosphere is located near the hif for the short period ( @xmath1 days ) lmc models . we also use the updated lmc data to derive empirical pc and ac relations at these phases . our numerical models are broadly consistent with our theory and the observed data , though we discuss some caveats in the paper . we apply the idea of the hif - photosphere interaction to explain recent suggestions that the lmc period - luminosity ( pl ) and pc relations are non - linear with a break at a period close to 10 days . our empirical lmc pc and pl relations are also found to be non - linear with the @xmath2-test . our explanation relies on the properties of the saha ionization equation , the hif - photosphere interaction and the way this interaction changes with the phase of pulsation and metallicity to produce the observed changes in the lmc pc and pl relations . cepheids stars : fundamental parameters . And you have already written the first three sentences of the full article: @xcite found that the galactic cepheids follow a spectral type that is independent of their pulsational periods at maximum light and gets later as the periods increase at minimum light . * hereafter skm ) used radiative hydrodynamical models to explain these observational phenomena as being due to the location of the hydrogen ionization front ( hif ) relative to the photosphere . their results agreed very well with code s observation .. Please generate the next two sentences of the article

skm further used the stefan - boltzmann law applied at the maximum and minimum light , together with the fact that radial variation is small in the optical @xcite , to derive : @xmath3 where @xmath4 are the effective temperature at the maximum / minimum light , respectively . if @xmath5 is independent of the pulsation period @xmath6 ( in days ) , then equation ( 1 ) predicts there is a relation between the @xmath7-band amplitude and the temperature ( or the colour ) at minimum light , and vice versa . in other words , if the period - colour ( pc ) relation at maximum ( or minimum ) light is flat , then there is an amplitude - colour ( ac ) relation at minimum ( or maximum ) light . equation ( 1 ) has shown to be valid theoretically and observationally for the classical cepheids and rr lyrae variables @xcite .

Suppose that you have an abstract for a scientific paper: the c - axis charge dynamics of copper oxide materials in the underdoped and optimally doped regimes has been studied by considering the incoherent interlayer hopping . it is shown that the c - axis charge dynamics for the chain copper oxide materials is mainly governed by the scattering from the in - plane fluctuation , and the c - axis charge dynamics for the no - chain copper oxide materials is dominated by the scattering from the in - plane fluctuation incorporating with the interlayer disorder , which would be suppressed when the holon pseudogap opens at low temperatures and lower doping levels , leading to the crossovers to the semiconducting - like range in the c - axis resistivity and the temperature linear to the nonlinear range in the in - plane resistivity . . And you have already written the first three sentences of the full article: it has become clear in the past several years that copper oxide materials are among the most complex systems studied in condensed matter physics , and show many unusual normal - state properties . the complications arise mainly from ( 1 ) strong anisotropy in the properties parallel and perpendicular to the cuo@xmath0 planes which are the key structural element in the whole copper oxide superconducting materials , and ( 2 ) extreme sensitivity of the properties to the compositions ( stoichiometry ) which control the carrier density in the cuo@xmath0 plane @xcite , while the unusual normal - state feature is then closely related to the fact that these copper oxide materials are doped mott insulators , obtained by chemically adding charge carriers to a strongly correlated antiferromagnetic ( af ) insulating state , therefore the physical properties of these systems mainly depend on the extent of dopings , and the regimes have been classified into the underdoped , optimally doped , and overdoped , respectively @xcite . the normal - state properties of copper oxide materials in the underdoped and optimally doped regimes exhibit a number of anomalous properties in the sense that they do not fit in the conventional fermi - liquid theory @xcite , and the mechanism for the superconductivity in copper oxide materials has been widely recognized to be closely associated with the anisotropic normal - state properties @xcite . among the striking features of the normal - state properties in the underdoped and optimally doped regimes , the physical quantity which most evidently displays the anisotropic property in copper oxide materials is the charge dynamics @xcite , which is manifested by the optical conductivity and resistivity .. Please generate the next two sentences of the article

it has been show from the experiments that the in - plane charge dynamics is rather universal within the whole copper oxide materials @xcite . the in - plane optical conductivity for the same doping is nearly materials independent both in the magnitude and energy dependence , and shows the non - drude behavior at low energies and anomalous midinfrared band in the charge - transfer gap , while the in - plane resistivity @xmath1 exhibits a linear behavior in the temperature in the optimally doped regime and a nearly temperature linear dependence with deviations at low temperatures in the underdoped regime @xcite .

Suppose that you have an abstract for a scientific paper: we present a new technique that combines off - axis digital holography and dark field microscopy to track @xmath0 gold particles diffusing in water . we show that a single hologram is sufficient to localize several particles in a thick sample with a localization accuracy independent of the particle position . from our measurements we reconstruct the trajectories of the particles and derive their 3d diffusion coefficient . our results pave the way for quantitative studies of the motion of single nanoparticle in complex media . 99 b. huang , w. wang , m. bates , and x. zhuang , `` three - dimensional super - resolution imaging by stochastic optical reconstruction microscopy , '' science * 319 , * 810 ( 2008 ) . j. bewersdorf , b.t . bennett , and k.l . knight , `` h2ax chromatin structures and their response to dna damage revealed by 4pi microscopy , '' proc . nat . acad . sci . usa * 103 , * 18137 ( 2006 ) . s.r . pavani , m.a . thompson , j.s . biteen , s.j . lord , n. liu , r.j . twieg , r. piestun , and w.e . moerner , `` three - dimensional , single - molecule fluorescence imaging beyond the diffraction limit by using a double - helix point spread function , '' proc . nat . acad . sci . usa * 106 , * 2995 ( 2009 ) . m.f juette , t.j . gould , m.d . lessard , m.j . mlodzianoski , b.s . nagpure , b.t . bennett , s.t . hess , and j. bewersdorf , `` three - dimensional sub100 nm resolution fluorescence microscopy of thick samples , '' nature methods * 5 , * 527529 ( 2008 ) . s. ram , p. prabhat , j. chao , e.s . ward , and r.j . ober , `` high accuracy 3d quantum dot tracking with multifocal plane microscopy for the study of fast intracellular dynamics in live cells , '' biophysical journal * 95 , * 6025 ( 2008 ) . u. schnars and w. jptner , `` direct recording of holograms by a ccd target and numerical reconstruction , '' 179181 ( 1994 ) . e. leith and j. upatniek , `` wavefront reconstruction photography , '' physics.... And you have already written the first three sentences of the full article: the study of cellular processes at the single - molecule level is a flourishing field of research in biology . individual molecules labeled with sub - micron markers can now be tracked in a cellular environment , and quantitative information about their dynamics can be obtained by reconstructing their trajectory . one of the most used techniques for this purpose is single - molecule fluorescence microscopy ( smfm ) , which relies on a labeling with nanometer - sized fluorescent markers such as organic dyes or quantum dots .. Please generate the next two sentences of the article

but standard smfm provides no information on the axial position of the marker , limiting this technique to 2d tracking . recent improvements of smfm such as astigmatism optic@xcite , @xmath1pi microscopy @xcite , double - helix psf @xcite , or multi - planes detection @xcite have made possible 3d tracking . since the depth of field of these techniques is limited to a few microns , 3d tracking of molecules that explore larger distances in the thickness of a sample requires to continuously adjust the position of the focal plane of the microscope objective , which strongly limits the time resolution .

Suppose that you have an abstract for a scientific paper: a pedagogical overview of strange quark matter and strange stars is presented . after a historical notation of the research and an introduction to quark matter , a major part is devoted to the physics and astrophysics of strange stars , with attention being paid to the possible ways by which neutron stars and strange stars can be distinguished in astrophysics . recent possible evidence for _ bare _ strange stars is also discussed . # 1_#1 _ # 1_#1 _ = # 1 1.25 in .125 in .25 in . And you have already written the first three sentences of the full article: soon after the fermi - dirac form ( in 1926 ) of statistical mechanics was proposed for particles which obey pauli s exclusion principle ( in 1925 ) , fowler ( 1926 ) realized that the electron degeneracy pressure can balance for those stars , called as white dwarfs , discovered by astronomers in 1914 . by a numerical calculation ( 1931 ) for a polytropic gas of extremely relativistic electrons , chandrasekhar found a unique mass , which was interpreted as a mass limit of white dwarfs . landau ( 1932 ) presented an elementary explanation of the chandrasekhar limit by considering the lowest total energy of stars , and recognized that increasing density favors energetically the formation of neutrons , discovered only several months before by chadwick , through the action @xmath0 . a very massive object with much high density may have almost neutrons in the chemical equilibrium , which was then called as _ neutron stars _ ( nss ) .. Please generate the next two sentences of the article

detailed calculations of ns structures showed ( e.g. , oppenheimer & volkoff 1939 ) that an ns can have a mass of @xmath1 , but is only @xmath2 km in radius , which makes it hard to be observed by astronomers . however , on one hand , a few authors do investigate possible astrophysical implications of nss .

Suppose that you have an abstract for a scientific paper: this article reviews and updates the standard model prediction of the @xmath0 lepton @xmath1@xmath2@xmath3 . updated qed and electroweak contributions are presented , together with new values of the leading - order hadronic term , based on the recent low energy @xmath4 data from babar , cmd-2 , kloe and snd , and of the hadronic light - by - light contribution . the total prediction is confronted to the available experimental bounds on the @xmath0 lepton anomaly , and prospects for its future measurements are briefly discussed . . And you have already written the first three sentences of the full article: numerous precision tests of the standard model ( sm ) and searches for its possible violation have been performed in the last few decades , serving as an invaluable tool to test the theory at the quantum level . they have also provided stringent constraints on many `` new physics '' ( np ) scenarios . a typical example is given by the measurements of the anomalous magnetic moment of the electron and the muon , where recent experiments reached the fabulous relative precision of 0.7 ppb @xcite and 0.5 ppm,@xcite respectively .. Please generate the next two sentences of the article

these experiments measure the so - called gyromagnetic factor @xmath1 , defined by the relation between the particle s spin @xmath5 and its magnetic moment @xmath6 , = g , where @xmath7 and @xmath8 are the charge and mass of the particle . in the dirac theory of a charged point - like spin-@xmath9 particle , @xmath10 . quantum electrodynamics ( qed ) predicts deviations from dirac s value , as the charged particle can emit and reabsorb virtual photons .

Suppose that you have an abstract for a scientific paper: collimator angle is usually rotated when planning volumetric modulated arc therapy ( vmat ) due to the leakage of radiation between multi - leaf collimator ( mlc ) leaves . we studied the effect of the collimator angles on the results of dosimetric verification of the vmat plans for head and neck patients . we studied vmat plans for 10 head and neck patients . we made 2 sets of vmat plans for each patient . each set was composed of 10 plans with collimator angles of 0 , 5 , 10 , 15 , 20 , 25 , 30 , 35 , 40 , 45 degrees . plans in the first set were optimized individually and plans in the second set shared the 30 degree collimator angle optimization . two sets of plans were verified using the 2-dimensional ion chamber array matrixx ( iba dosimetry , germany ) . the comparison between the calculation and measurements were made by the @xmath0-index analysis . the @xmath0-index ( 2%/2 mm ) and ( 3%/3 mm ) passing rates had negative correlations with the collimator angle . maximum difference between @xmath0-index ( 3%/3 mm ) passing rates of different collimator angles for each patient ranged from 1.46% to 5.60% with an average of 3.67% . there were significant differences ( maximum 5.6% ) in the passing rates of different collimator angles . the results suggested that the accuracy of the delivered dose depends on the collimator angle . these findings are informative when choosing a collimator angle in vmat plans . . And you have already written the first three sentences of the full article: intensity modulated radiation therapy ( imrt ) is usually used for head and neck cancer patients because it delivers highly conformal radiation doses to the target with reduction of toxicity to normal organs , as compared with conventional radiation therapy techniques @xcite . volumetric modulated arc therapy ( vmat ) is a novel imrt technique . vmat has less mu , less treatment time , high quality planning and more efficiency than static gantry angle imrt @xcite . during vmat the linear accelerator ( linac ) control system changes the dose rate and the multi leaf collimator ( mlc ) positions while gantry is rotating around the patient .. Please generate the next two sentences of the article

collimator angle is usually rotated in the plans of vmat to reduce radiation leakage between mlc leaves . at a zero angle , the leakage between mlc leaves accumulates during the gantry rotation and the summed leakage results in unwanted dose distributions , which can not be controlled by optimization . at different collimator angles ,

Suppose that you have an abstract for a scientific paper: we present the single - epoch black hole mass estimators based on the @xmath01549 broad emission line , using the updated sample of the reverberation - mapped agns and high - quality uv spectra . by performing multi - component spectral fitting analysis , we measure the line widths ( fwhm@xmath1 and line dispersion , @xmath2 ) and the continuum luminosity at 1350 ( @xmath3 ) to calibrate the -based mass estimators . by comparing with the h@xmath4 reverberation - based masses , we provide new mass estimators with the best - fit relationships , i.e. , @xmath5 and @xmath6 . the new -based mass estimators show significant mass - dependent systematic difference compared to the estimators commonly used in the literature . using the published sloan digital sky survey qso catalog , we show that the black hole mass of high - redshift qsos decreases on average by @xmath7 dex if our recipe is adopted . . And you have already written the first three sentences of the full article: understanding the growth history of supermassive black holes ( smbhs ) is one of the fundamental issues in studies of galaxy formation and evolution . the intimate connection between smbhs and host galaxies is evidenced through empirical correlations between the masses of smbhs ( m@xmath8 ) and the overall properties of the host galaxy spheroids ( e.g. , magorrian et al . 1998 ; ferraresse & merritt 2000 ; gebhardt et al .. Please generate the next two sentences of the article

the cosmic evolution of these scaling relationships has been investigated in the literature , where a tentative evolution has been reported utilizing observational approaches ( e.g. , peng et al . 2006 ; woo et al .

Suppose that you have an abstract for a scientific paper: we investigate the two - word naming game on two - dimensional random geometric graphs . studying this model advances our understanding of the spatial distribution and propagation of opinions in social dynamics . a main feature of this model is the spontaneous emergence of spatial structures called opinion domains which are geographic regions with clear boundaries within which all individuals share the same opinion . we provide the mean - field equation for the underlying dynamics and discuss several properties of the equation such as the stationary solutions and two - time - scale separation . for the evolution of the opinion domains we find that the opinion domain boundary propagates at a speed proportional to its curvature . finally we investigate the impact of committed agents on opinion domains and find the scaling of consensus time . @xmath0 department of mathematical sciences , rensselaer polytechnic institute , 110 8@xmath1 street , troy , ny , 12180 - 3590 usa + @xmath2 department of physics , applied physics and astronomy , rensselaer polytechnic institute , 110 8@xmath1 street , troy , ny , 12180 - 3590 usa + @xmath3 department of computer science , rensselaer polytechnic institute , 110 8@xmath1 street , troy , ny , 12180 - 3590 usa + @xmath4 e - mail : zhangw14@rpi.edu relevant features of social and opinion dynamics @xcite can be investigated by prototypical agent - based models such as the voter model @xcite , the naming game @xcite , or the majority model @xcite . these models typically include a large number of individuals , each of which is assigned a state defined by the social opinions that it accepts and updates its state by interacting with its neighbors . opinion dynamics driven by local communication on geographically embedded networks is of great interest to understanding the spatial distribution and propagation of opinions . in this paper we investigate the naming game ( ng ) on random geometric graphs as a minimum model of this type . we focus on the ng but.... And you have already written the first three sentences of the full article: we begin with the definitions of the essential concepts of our model . * random geometric graph * consists of @xmath10 agents randomly distributed in a unit square @xmath11 . each agent has an interaction range defined by @xmath12 , where @xmath5 is the local interaction radius .. Please generate the next two sentences of the article

two agents are connected if they fall in each others interaction range . the choice of network topology , denoted as @xmath13 , impacts the boundary conditions .

Suppose that you have an abstract for a scientific paper: measurements with an atomic force microscope ( afm ) offer a direct way to probe elastic properties of lipid bilayer membranes locally : provided the underlying stress - strain relation is known , material parameters such as surface tension or bending rigidity may be deduced . in a recent experiment a pore - spanning membrane was poked with an afm tip , yielding a linear behavior of the force - indentation curves . a theoretical model for this case is presented here which describes these curves in the framework of helfrich theory . the linear behavior of the measurements is reproduced if one neglects the influence of adhesion between tip and membrane . including it via an adhesion balance changes the situation significantly : force - distance curves cease to be linear , hysteresis and nonzero detachment forces can show up . the characteristics of this rich scenario are discussed in detail in this article . . And you have already written the first three sentences of the full article: lipid bilayer membranes constitute one of the most fundamental components of all living cells . apart from their obvious _ structural _ role in organizing distinct biochemical compartments , their contributions to essential _ functions _ such as protein organization , sorting , or signalling are now well documented @xcite . in fact , their tasks significantly exceed mere passive separation or solubilization of proteins , since often _. Please generate the next two sentences of the article

mechanical _ membrane properties are intricately linked to these biological functions , most visibly in all cases which go along with distinct membrane deformations , such as exo- and endocytosis @xcite , vesiculation @xcite , viral budding @xcite , cytoskeleton interaction @xcite , and cytokinesis @xcite . consequently , a quantitative knowledge of the material parameters which characterize a membrane s elastic response most notably the bending modulus @xmath0 is also biologically desirable .

Suppose that you have an abstract for a scientific paper: precision doppler velocity measurements from the 3.9m anglo - australian telescope reveal a planet with a 6 year period orbiting the g5 dwarf hd 70642 . the a = 3.3 au orbit has a low eccentricity ( e = 0.1 ) , and the minimum ( @xmath0 ) mass of the planet is 2.0 m@xmath1 . the host star is metal rich relative to the sun , similar to most stars with known planets . the distant and approximately circular orbit of this planet makes it a member of a rare group to emerge from precision doppler surveys . . And you have already written the first three sentences of the full article: of the 77 extrasolar planets currently listed by the iau working group on extrasolar planets ] ( including planet candidates published in a refereed journals with @xmath0@xmath2 10 m@xmath1 ) , only three systems have been found to harbor planets in circular orbits ( e @xmath2 0.1 ) orbits beyond 0.5 au 47 uma ( fischer et al . 2002 ; butler & marcy 1996 ) , hd 27442 ( butler et al . 2001 ) , and hd 4208 ( vogt et al . 2002 ) . with 13 `` 51 peg . Please generate the next two sentences of the article

type '' planets ( p @xmath2 5 d ) , and @xmath360 eccentric planets ( e @xmath4 0.1 ) , the long period circular orbits are the rarest of the three types of planetary systems to emerge over the last 8 years . with one exception , all the iau working group list planets orbit within 4 au of their host stars .

Suppose that you have an abstract for a scientific paper: we present a new optical tully - fisher ( tf ) investigation for a complete , full - sky sample of 297 sb@xmath0sc spirals with redshifts between 4500 and 7000 . the survey was specifically designed to provide _ uniform , well - calibrated _ data over both hemispheres . all previous tf surveys within the supergalactic shell ( @xmath1 ) have relied on matching separate data sets in the northern and southern hemispheres and thus can not attain full - sky homogeneity . analyses of the cosmological dipole and peculiar velocities based on these studies have produced contradictory claims for the amplitude of the bulk flow and whether it is generated by internal or external mass fluctuations . with shellflow , and further zero - point calibration of existing tf data sets , we expect a high - accuracy detection of the bulk flow amplitude and an unambiguous characterization of the tidal field at 6000 . # 1#1@xmath2 . And you have already written the first three sentences of the full article: peculiar velocity surveys covering a fair fraction of the sky are now reaching to 6000 and beyond ( @xcite , @xcite , @xcite , @xcite , @xcite , @xcite ) and are being interpreted as evidence for substantial flows on these scales ( @xcite , @xcite , @xcite , @xcite , @xcite , @xcite ) . however , the amplitude , direction , and scale of these flows remain very much in contention , with resulting uncertainties in the theoretical interpretation and implications of these measurements ( @xcite , @xcite ) . indeed , recently published conflicting results suggest that the motion of the lg is either due , or is not due , to material within 6000 , and that _ iras _ galaxies either trace , or do not trace , the dark matter which gives rise to the observed peculiar velocities . the most recent potent reconstruction of the markiii velocities ( @xcite ) shows that the bulk velocity can be decomposed into two components arising from the mass fluctuation field within the sphere of radius @xmath3 about the lg and a component dominated by the mass distribution outside that volume . for convenience. Please generate the next two sentences of the article

, we refer to this boundary at @xmath3 as the `` supergalactic shell '' since it includes the main local attractors in the supergalactic plane , the great attractor and perseus - pisces . this new analysis shows dominant infall patterns by the ga and pp but very little bulk flow within the supergalactic shell .