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The waste stream is irradiated with Ultraviolet radiation. The UV radiation disinfect by disrupting the pathogen cell to be mutated and prevent the cell from replicating. Eventually the mutated cell becomes extinct and this process eliminates odour. | 5 | Separation Processes |
Incandescence is the emission of electromagnetic radiation (including visible light) from a hot body as a result of its high temperature. The term derives from the Latin verb incandescere, to glow white. A common use of incandescence is the incandescent light bulb, now being phased out.
Incandescence is due to thermal radiation. It usually refers specifically to visible light, while thermal radiation refers also to infrared or any other electromagnetic radiation. | 0 | Luminescence |
The Morin transition (also known as a spin-flop transition) is a magnetic phase transition in α-FeO hematite where the antiferromagnetic ordering is reorganized from being aligned perpendicular to the c-axis to be aligned parallel to the c-axis below T.
T = 260K for Fe in α-FeO.
A change in magnetic properties takes place at the Morin transition temperature. | 7 | Magnetic Ordering |
Ultraviolet radiation can aggravate several skin conditions and diseases, including systemic lupus erythematosus, Sjögrens syndrome, Sinear Usher syndrome, rosacea, dermatomyositis, Dariers disease, Kindler–Weary syndrome and Porokeratosis. | 8 | Ultraviolet Radiation |
Electrofiltration is a method that combines membrane filtration and electrophoresis in a dead-end process.
Electrofiltration is regarded as an appropriate technique for concentration and fractionation of biopolymers. The film formation on the filter membrane which hinders filtration can be minimized or completely avoided by the application of electric field, improving filtration’s performance and increasing selectivity in case of fractionation. This approach reduces significantly the expenses for downstream processing in bioprocesses. | 5 | Separation Processes |
The sonoluminescence effect was first discovered at the University of Cologne in 1934 as a result of work on sonar. Hermann Frenzel and H. Schultes put an ultrasound transducer in a tank of photographic developer fluid. They hoped to speed up the development process. Instead, they noticed tiny dots on the film after developing and realized that the bubbles in the fluid were emitting light with the ultrasound turned on. It was too difficult to analyze the effect in early experiments because of the complex environment of a large number of short-lived bubbles. This phenomenon is now referred to as multi-bubble sonoluminescence (MBSL).
In 1960, Peter Jarman from Imperial College of London proposed the most reliable theory of sonoluminescence phenomenon. He concluded that sonoluminescence is basically thermal in origin and that it might possibly arise from microshocks with the collapsing cavities.
In 1990, an experimental advance was reported by Gaitan and Crum, who produced stable single-bubble sonoluminescence (SBSL). In SBSL, a single bubble trapped in an acoustic standing wave emits a pulse of light with each compression of the bubble within the standing wave. This technique allowed a more systematic study of the phenomenon because it isolated the complex effects into one stable, predictable bubble. It was realized that the temperature inside the bubble was hot enough to melt steel, as seen in an experiment done in 2012; the temperature inside the bubble as it collapsed reached about . Interest in sonoluminescence was renewed when an inner temperature of such a bubble well above was postulated. This temperature is thus far not conclusively proven; rather, recent experiments indicate temperatures around . | 0 | Luminescence |
* Due to the structure, the pressure difference is theoretically limited to atmospheric pressure (1 bar), and in practice somewhat lower.
* Besides the drum, other accessories, for example, agitators and vacuum pump, vacuum receivers, slurry pumps are required.
* The discharge cake contains residual moisture.
* The cake tends to crack due to their air drawn through by the vacuum system, so that washing and drying are not efficient.
* High energy consumption by the vacuum pump. | 5 | Separation Processes |
(Z)-Stilbene is a diarylethene, that is, a hydrocarbon consisting of a cis ethene double bond substituted with a phenyl group on both carbon atoms of the double bond. The name stilbene was derived from the Greek word , which means shining. | 0 | Luminescence |
In a hexagonal system the axis is an axis of sixfold rotation symmetry. The energy density is, to fourth
order,
The uniaxial anisotropy is mainly determined by these first two terms. Depending on the values and , there are four different kinds of anisotropy (isotropic, easy axis, easy plane and easy cone):
* : the ferromagnet is isotropic.
* and : the axis is an easy axis.
* and : the basal plane is an easy plane.
* and : the basal plane is an easy plane.
* : the ferromagnet has an easy cone (see figure to right).
The basal plane anisotropy is determined by the third term, which is sixth-order. The easy directions are projected onto three axes in the basal plane.
Below are some room-temperature anisotropy constants for hexagonal ferromagnets. Since all the values of and are positive, these materials have an easy axis.
Higher order constants, in particular conditions, may lead to first order magnetization processes FOMP. | 7 | Magnetic Ordering |
UV light is electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays. UV is categorised into several wavelength ranges, with short-wavelength UV (UV-C) considered "germicidal UV". Wavelengths between about 200 nm and 300 nm are strongly absorbed by nucleic acids. The absorbed energy can result in defects including pyrimidine dimers. These dimers can prevent replication or can prevent the expression of necessary proteins, resulting in the death or inactivation of the organism. Recently, it has been shown that these dimers are fluorescent.
* Mercury-based lamps operating at low vapor pressure emit UV light at the 253.7 nm line.
* Ultraviolet light-emitting diode (UV-C LED) lamps emit UV light at selectable wavelengths between 255 and 280 nm.
* Pulsed-xenon lamps emit UV light across the entire UV spectrum with a peak emission near 230 nm.
This process is similar to, but stronger than, the effect of longer wavelengths (UV-B) producing sunburn in humans. Microorganisms have less protection against UV and cannot survive prolonged exposure to it.
A UVGI system is designed to expose environments such as water tanks, rooms and forced air systems to germicidal UV. Exposure comes from germicidal lamps that emit germicidal UV at the correct wavelength, thus irradiating the environment. The forced flow of air or water through this environment ensures exposure of that air or water. | 8 | Ultraviolet Radiation |
Cell culture techniques make it possible to produce epithelial sheets for the replacement of damaged oral mucosa. Partial-thickness tissue engineering uses one type of cell layer, this can be in monolayers or multilayers. Monolayer epithelial sheets suffice for the study of the basic biology of oral mucosa, for example its responses to stimuli such as mechanical stress, growth factor addition and radiation damage. Oral mucosa, however, is a complex multilayer structure with proliferating and differentiating cells and monolayer epithelial sheets have been shown to be fragile, difficult to handle and likely to contract without a supporting extracellular matrix. Monolayer epithelial sheets can be used to manufacture multilayer cultures. These multilayer epithelial sheets show signs of differentiation such as the formation of a basement membrane and keratinization. Fibroblasts are the most common cells in extracellular matrix and are important for epithelial morphogenesis. If fibroblasts are absent from the matrix, the epithelium stops proliferating but continues to differentiate. The structures obtained by partial-thickness oral mucosa engineering form the basis for full-thickness oral mucosa engineering. | 2 | Tissue Engineering |
Lectins are widespread in nature, and many foods contain the proteins. Some lectins can be harmful if poorly cooked or consumed in great quantities. They are most potent when raw as boiling, stewing or soaking in water for several hours can render most lectins inactive. Cooking raw beans at low heat, though, such as in a slow cooker, will not remove all the lectins.
Some studies have found that lectins may interfere with absorption of some minerals, such as calcium, iron, phosphorus, and zinc. The binding of lectins to cells in the digestive tract may disrupt the breakdown and absorption of some nutrients, and as they bind to cells for long periods of time, some theories hold that they may play a role in certain inflammatory conditions such as rheumatoid arthritis and type 1 diabetes, but research supporting claims of long-term health effects in humans is limited and most existing studies have focused on developing countries where malnutrition may be a factor, or dietary choices are otherwise limited. | 6 | Carbohydrates |
In 1949 expatriate German Ronald Richter proposed the Huemul Project in Argentina, announcing positive results in 1951. These turned out to be fake, but prompted others' interest. Lyman Spitzer began considering ways to solve problems involved in confining a hot plasma, and, unaware of the Z-pinch efforts, he created the stellarator. Spitzer applied to the US Atomic Energy Commission for funding to build a test device.
During this period, James L. Tuck, who had worked with the UK teams on Z-pinch, had been introducing the stellarator concept to his coworkers at LANL. When he heard of Spitzer's pitch, he applied to build a pinch machine of his own, the Perhapsatron.
Spitzer's idea won funding and he began work under Project Matterhorn. His work led to the creation of Princeton Plasma Physics Laboratory (PPPL). Tuck returned to LANL and arranged local funding to build his machine. By this time it was clear that the pinch machines were afflicted by instability, stalling progress. In 1953, Tuck and others suggested solutions that led to a second series of pinch machines, such as the ZETA and Sceptre devices.
Spitzers first machine, A worked, but his next one, B', suffered from instabilities and plasma leakage.
In 1954 AEC chair Lewis Strauss foresaw electricity as "too cheap to meter". Strauss was likely referring to fusion power, part of the secret Project Sherwood—but his statement was interpreted as referring to fission. The AEC had issued more realistic testimony regarding fission to Congress months before, projecting that "costs can be brought down... [to]... about the same as the cost of electricity from conventional sources..." | 3 | Nuclear Fusion |
A common method of freezing lesions is by using liquid nitrogen as the cryogen. The liquid nitrogen may be applied to lesions using a variety of methods; such as dipping a cotton or synthetic material tipped applicator in liquid nitrogen and then directly applying the cryogen onto the lesion. The liquid nitrogen can also be sprayed onto the lesion using a spray canister. The spray canister may utilize a variety of nozzles for different spray patterns. A cryoprobe, which is a metal applicator that has been cooled using liquid nitrogen, can also be directly applied onto lesions. | 1 | Cryobiology |
Organoids offer researchers an exceptional model to study developmental biology. Since the identification of pluripotent stem cells, there have been great advancements in directing pluripotent stem cells fate in vitro using 2D cultures. These advancements in PSC fate direction, coupled with the advancements in 3D culturing techniques allowed for the creation of organoids that recapitulate the properties of various specific subregions of a multitude of organs. The use of these organoids has thus greatly contributed to expanding our understanding of the processes of organogenesis, and the field of developmental biology. In central nervous system development, for example, organoids have contributed to our understanding of the physical forces that underlie retinal cup formation. More recent work has extended cortical organoid growth periods extensively and at nearly a year under specific differentiation conditions, the organoids persist and have some features of human fetal development stages. | 2 | Tissue Engineering |
One application of SPMR is the detection of disease and cancer. This is accomplished by functionalizing the NP with biomarkers, including cell antibodies (Ab). The functionalized NP+Ab may be subsequently attached to cells targeted by the biomarker in cell cultures, blood and marrow samples, as well as animal models.
A variety of biochemical procedures are used to conjugate the NP with the biomarker. The resulting NP+Ab are either directly mixed with incubated blood or diseased cells, or injected into animals. Following injection the functionalized NP reside in the bloodstream until encountering cells that are specific to the biomarker attached to the Ab.
Conjugation of NP with Ab followed by attachment to cells is accomplished by identifying particular cell lines expressing varying levels of the Ab by flow cytometry. The Ab is conjugated to the superparamagnetic iron oxide NP by different methods including the carbodiimide method. The conjugated NP+Ab are then incubated with the cell lines and may be examined by transmission-electron microscopy (TEM) to confirm that the NP+Ab are attached to the cells. Other methods to determine whether NP are present on the surface of the cell are confocal microscopy, Prussian blue histochemistry, and SPMR. The resulting carboxylate functionality of the polymer-encapsulated NPs by this method allows conjugation of amine groups on the Ab to the carboxylate anions on the surface of the NPs using standard two-step EDC/NHS chemistry. | 7 | Magnetic Ordering |
Animal studies have shown the benefit of targeted temperature management in traumatic central nervous system (CNS) injuries. Clinical trials have shown mixed results with regards to the optimal temperature and delay of cooling. Achieving therapeutic temperatures of is thought to prevent secondary neurological injuries after severe CNS trauma. A systematic review of randomised controlled trials in traumatic brain injury (TBI) suggests there is no evidence that hypothermia is beneficial. | 1 | Cryobiology |
In the late 1960s it was discovered that illuminated organic dyes can generate electricity at oxide electrodes in electrochemical cells. In an effort to understand and simulate the primary processes in photosynthesis the phenomenon was studied at the University of California at Berkeley with chlorophyll extracted from spinach (bio-mimetic or bionic approach). On the basis of such experiments electric power generation via the dye sensitization solar cell (DSSC) principle was demonstrated and discussed in 1972. The instability of the dye solar cell was identified as a main challenge. Its efficiency could, during the following two decades, be improved by optimizing the porosity of the electrode prepared from fine oxide powder, but the instability remained a problem.
A modern n-type DSSC, the most common type of DSSC, is composed of a porous layer of titanium dioxide nanoparticles, covered with a molecular dye that absorbs sunlight, like the chlorophyll in green leaves. The titanium dioxide is immersed under an electrolyte solution, above which is a platinum-based catalyst. As in a conventional alkaline battery, an anode (the titanium dioxide) and a cathode (the platinum) are placed on either side of a liquid conductor (the electrolyte).
The working principle for n-type DSSCs can be summarized into a few basic steps. Sunlight passes through the transparent electrode into the dye layer where it can excite electrons that then flow into the conduction band of the n-type semiconductor, typically titanium dioxide. The electrons from titanium dioxide then flow toward the transparent electrode where they are collected for powering a load. After flowing through the external circuit, they are re-introduced into the cell on a metal electrode on the back, also known as the counter electrode, and flow into the electrolyte. The electrolyte then transports the electrons back to the dye molecules and regenerates the oxidized dye.
The basic working principle above, is similar in a p-type DSSC, where the dye-sensitised semiconductor is of p-type nature (typically nickel oxide). However, instead of injecting an electron into the semiconductor, in a p-type DSSC, a hole flows from the dye into the valence band of the p-type semiconductor.
Dye-sensitized solar cells separate the two functions provided by silicon in a traditional cell design. Normally the silicon acts as both the source of photoelectrons, as well as providing the electric field to separate the charges and create a current. In the dye-sensitized solar cell, the bulk of the semiconductor is used solely for charge transport, the photoelectrons are provided from a separate photosensitive dye. Charge separation occurs at the surfaces between the dye, semiconductor and electrolyte.
The dye molecules are quite small (nanometer sized), so in order to capture a reasonable amount of the incoming light the layer of dye molecules needs to be made fairly thick, much thicker than the molecules themselves. To address this problem, a nanomaterial is used as a scaffold to hold large numbers of the dye molecules in a 3-D matrix, increasing the number of molecules for any given surface area of cell. In existing designs, this scaffolding is provided by the semiconductor material, which serves double-duty. | 8 | Ultraviolet Radiation |
Each TERMIS chapter has defined awards to recognize outstanding scientists and their contributions within the community. | 2 | Tissue Engineering |
In white dwarfs, the core of the star is cold, under which conditions, so, if treated classically, the nuclei that arrange themselves into a crystal lattice are in their ground state. The zero-point oscillations of nuclei in the crystal lattice with energy at the energy at Gamow's peak equal to can overcome the Coulomb barrier, actuating pycnonuclear reactions. A semi-analytical model indicates that in white dwarfs, a thermonuclear runaway can occur at much earlier ages than that of the universe, as the pycnonuclear reactions in the cores of white dwarfs exceed the luminosity of the white dwarfs, allowing C-burning to occur, which catalyzes the formation of type Ia supernovas in accreting white dwarfs, whose mass is equal to the Chandrasekhar mass.
Some studies indicate that the contribution of pycnonuclear reactions towards instability of white dwarfs is only significant in carbon white dwarfs, while in oxygen white dwarfs, such instability is caused mostly due to electron capture. Although other authors disagree that the pycnonuclear reactions can act as major long-term heating sources for massive (1.25 ) white dwarfs, as their density would not suffice for a high rate of pycnonuclear reactions.
While most studies indicate that at the end of their lifecycle, white dwarfs slowly decay into black dwarfs, where pycnonuclear reactions slowly turn their cores into , according to some versions, a collapse of black dwarfs is possible: M.E. Caplan (2020) theorizes that in the most massive black dwarfs (1.25 ), due to their declining electron fraction resulting from production, they will exceed the Chandrasekhar limit in the very far future, speculating that their lifetime and delay time can stretch to up to years. | 3 | Nuclear Fusion |
Alpha-glucosidases are targeted by alpha-glucosidase inhibitors such as acarbose and miglitol to control diabetes mellitus type 2. | 6 | Carbohydrates |
Co-translational O-GlcNAc has been identified on Sp1 and Nup62. This modification suppresses co-translational ubiquitination and thus protects nascent polypeptides from proteasomal degradation. Similar protective effects of O-GlcNAc on full-length Sp1 have been observed. It is unknown if this pattern is universal or only applicable to specific proteins.
Protein phosphorylation is often used as a mark for subsequent degradation. Tumor suppressor protein p53 is targeted for proteasomal degradation via COP9 signalosome-mediated phosphorylation of T155. O-GlcNAcylation of p53 S149 has been associated with decreased T155 phosphorylation and protection of p53 from degradation. β-catenin O-GlcNAcylation competes with T41 phosphorylation, which signals β-catenin for degradation, stabilizing the protein.
O-GlcNAcylation of the Rpt2 ATPase subunit of the 26S proteasome has been shown to inhibit proteasome activity. Testing various peptide sequences revealed that this modification slows proteasomal degradation of hydrophobic peptides, degradation of hydrophilic peptides does not appear to be affected. This modification has been shown to suppress other pathways that activate the proteasome such as Rpt6 phosphorylation by cAMP-dependent protein kinase.
OGA-S localizes to lipid droplets and has been proposed to locally activate the proteasome to promote remodeling of lipid droplet surface proteins. | 6 | Carbohydrates |
The purpose of dynamic micromagnetics is to predict the time evolution of the magnetic configuration of a sample subject to some non-steady conditions such as the application of a field pulse or an AC field. This is done by solving the Landau-Lifshitz-Gilbert equation, which is a partial differential equation describing the evolution of the magnetization in terms of the local effective field acting on it. | 7 | Magnetic Ordering |
The observed magnetic anisotropy in an object can happen for several different reasons. Rather than having a single cause, the overall magnetic anisotropy of a given object is often explained by a combination of these different factors:
; Magnetocrystalline anisotropy: The atomic structure of a crystal introduces preferential directions for the magnetization.
; Shape anisotropy: When a particle is not perfectly spherical, the demagnetizing field will not be equal for all directions, creating one or more easy axes.
; Magnetoelastic anisotropy: Tension may alter magnetic behaviour, leading to magnetic anisotropy.
; Exchange anisotropy: Occurs when antiferromagnetic and ferromagnetic materials interact. | 7 | Magnetic Ordering |
The photo-oxidation of polymers can be investigated by either natural or accelerated weather testing. Such testing is important in determining the expected service-life of plastic items as well as the fate of waste plastic.
In natural weather testing, polymer samples are directly exposed to open weather for a continuous period of time, while accelerated weather testing uses a specialized test chamber which simulates weathering by sending a controlled amount of UV light and water at a sample. A test chamber may be advantageous in that the exact weathering conditions can be controlled, and the UV or moisture conditions can be made more intense than in natural weathering. Thus, degradation is accelerated and the test is less time-consuming.
Through weather testing, the impact of photooxidative processes on the mechanical properties and lifetimes of polymer samples can be determined. For example, the tensile behavior can be elucidated through measuring the stress–strain curve for a specimen. This stress–strain curve is created by applying a tensile stress (which is measured as the force per area applied to a sample face) and measuring the corresponding strain (the fractional change in length). Stress is usually applied until the material fractures, and from this stress–strain curve, mechanical properties such as the Young’s modulus can be determined. Overall, weathering weakens the sample, and as it becomes more brittle, it fractures more easily. This is observed as a decrease in the yield strain, fracture strain, and toughness, as well as an increase in the Young’s modulus and break stress (the stress at which the material fractures).
Aside from measuring the impact of degradation on mechanical properties, the degradation rate of plastic samples can also be quantified by measuring the change in mass of a sample over time, as microplastic fragments can break off from the bulk material as degradation progresses and the material becomes more brittle through chain-scission. Thus, the percentage change in mass is often measured in experiments to quantify degradation.
Mathematical models can also be created to predict the change in mass of a polymer sample over the weathering process. Because mass loss occurs at the surface of the polymer sample, the degradation rate is dependent on surface area. Thus, a model for the dependence of degradation on surface area can be made by assuming that the rate of change in mass resulting from degradation is directly proportional to the surface area SA of the specimen:
Here, is the density and k is known as the specific surface degradation rate (SSDR), which changes depending on the polymer sample’s chemical composition and weathering environment. Furthermore, for a microplastic sample, SA is often approximated as the surface area of a cylinder or sphere. Such an equation can be solved to determine the mass of a polymer sample as a function of time. | 8 | Ultraviolet Radiation |
The number to be transferred depends on the number available, the age of the patient and other health and diagnostic factors. In countries such as Canada, the UK, Australia and New Zealand, a maximum of two embryos are transferred except in unusual circumstances. In the UK and according to HFEA regulations, a woman over 40 may have up to three embryos transferred, whereas in the US, there is no legal limit on the number of embryos which may be transferred, although medical associations have provided practice guidelines. Most clinics and country regulatory bodies seek to minimise the risk of multiple pregnancy, as it is not uncommon for multiple embryos to implant if multiple embryos are transferred. Embryos are transferred to the patient's uterus through a thin, plastic catheter, which goes through their vagina and cervix. Several embryos may be passed into the uterus to improve chances of implantation and pregnancy. | 1 | Cryobiology |
This basic concept is more correctly known as an aspirating skimmer, since some skimmer designs using an aspirator do not use a "Pin-Wheel"/"Adrian-Wheel" or "Needle-Wheel". "Pin-Wheel"/"Adrian-Wheel" describes the look of an impeller that consists of a disk with pins mounted perpendicular (90°) to the disc and parallel to the rotor. "Needle-Wheel" describes the look of an impeller that consists of a series of pins projecting out perpendicular to the rotor from a central axis. "Mesh-Wheel" describes the look of an impeller that consists of a mesh material attached to a plate or central axis on the rotor. The purpose of these modified impellers is to chop or shred the air that is introduced via an air aspirator apparatus or external air pump into very fine bubbles. The Mesh-Wheel design provides excellent results in the short term because of its ability to create fine bubbles with its thin cutting surfaces, but its propensity for clogging makes it an unreliable design.
The air aspirator differs from the venturi by the positioning of the water pump. With a venturi, the water is pushed through the unit, creating a vacuum to draw in air. With an air aspirator, the water is pulled through the unit, creating a vacuum to draw in air. These terms, however, are often incorrectly interchanged.
This style of protein skimmer has become very popular with public aquariums and is believed to be the most popular type of skimmer used with residential reef aquariums today. It has been particularly successful in smaller aquariums due to its usually compact size, ease of set up and use, and quiet operation. Since the pump is pushing a mixture of air and water, the power required to turn the rotor can be decreased and may result in a lower power requirement for that pump vs. the same pump with a different impeller when it is only pumping water. | 5 | Separation Processes |
The collective–amoeboid transition (CMT) is a process by which collective multicellular groups dissociate into amoeboid single cells following the down-regulation of integrins. CMTs contrast with epithelial–mesenchymal transitions (EMT) which occur following a loss of E-cadherin. Like EMTs, CATs are involved in the invasion of tumor cells into surrounding tissues, with amoeboid movement more likely to occur in soft extracellular matrix (ECM) and mesenchymal movement in stiff ECM. Although once differentiated, cells typically do not change their migration mode, EMTs and CMTs are highly plastic with cells capable of interconverting between them depending on intracelluar regulatory signals and the surrounding ECM.
CATs are the least common transition type in invading tumor cells, although they are noted in melanoma explants. | 2 | Tissue Engineering |
In the early 1970s Bussard became Assistant Director under Director Robert Hirsch at the Controlled Thermonuclear Reaction Division of what was then known as the Atomic Energy Commission. They founded the mainline fusion program for the United States: the Tokamak. In June 1995, Bussard claimed in a letter to all fusion laboratories, as well as to key members of the US Congress, that he and the other founders of the program supported the Tokamak not out of conviction that it was the best technical approach but rather as a vehicle for generating political support, thereby allowing them to pursue "all the hopeful new things the mainline labs would not try".
In a 1998 Analog magazine article, fellow fusion researcher Tom Ligon described an easily built demonstration fusor system along with some of Bussard's ideas for fusion reactors and incredibly powerful spacecraft propulsion systems, with which spacecraft could swiftly move throughout the solar system. | 3 | Nuclear Fusion |
In 2016, scientists in Japan announced they had successfully grown human skin in a lab. The skin was created using induced pluripotent stem cells, and when implanted in a mouse, the skin grew hairs successfully. Dr. Takashi Tsuji has sought donations for the group's research. The group has also formed a partnership with Organ Technologies and Kyocera Corporation to commercially develop the research. Organ Technologies secured funding from Kobayashi Pharmaceutical in late 2022 and was renamed to OrganTech in 2023. OrganTech hopes to transplant both regenerated hair follicle primordia and what they term "next-generation implants" into humans as soon as Q2 2024. | 2 | Tissue Engineering |
The hydrated proton is very acidic: at 25 °C, its pK is approximately 0. The values commonly given for pK(HO) are 0 or –1.74. The former uses the convention that the activity of the solvent in a dilute solution (in this case, water) is 1, while the latter uses the value of the concentration of water in the pure liquid of 55.5 M. Silverstein has shown that the latter value is thermodynamically unsupportable. The disagreement comes from the ambiguity that to define pK of HO in water, HO has to act simultaneously as a solute and the solvent. The IUPAC has not given an official definition of pK that would resolve this ambiguity. Burgot has argued that HO(aq) + HO (l) ⇄ HO (aq) + HO (aq) is simply not a thermodynamically well-defined process. For an estimate of pK(HO), Burgot suggests taking the measured value pK(HO) = 0.3, the pK of HO in ethanol, and applying the correlation equation pK = pK – 1.0 (± 0.3) to convert the ethanol pK to an aqueous value, to give a value of pK(HO) = –0.7 (± 0.3). On the other hand, Silverstein has shown that Ballinger and Longs experimental results support a pK of 0.0 for the aqueous proton. Neils and Schaertel provide added arguments for a pK' of 0.0
The aqueous proton is the most acidic species that can exist in water (assuming sufficient water for dissolution): any stronger acid will ionize and yield a hydrated proton. The acidity of (aq) is the implicit standard used to judge the strength of an acid in water: strong acids must be better proton donors than (aq), as otherwise a significant portion of acid will exist in a non-ionized state (i.e.: a weak acid). Unlike (aq) in neutral solutions that result from water's autodissociation, in acidic solutions, (aq) is long-lasting and concentrated, in proportion to the strength of the dissolved acid.
pH was originally conceived to be a measure of the hydrogen ion concentration of aqueous solution. Virtually all such free protons are quickly hydrated; acidity of an aqueous solution is therefore more accurately characterized by its concentration of (aq). In organic syntheses, such as acid catalyzed reactions, the hydronium ion () is used interchangeably with the ion; choosing one over the other has no significant effect on the mechanism of reaction. | 4 | Acids + Bases |
** HIF-2010 Symposium in Darmstadt, Germany. Robert J Burke presented on Single Pass (Heavy Ion Fusion) HIF and Charles Helsley made a presentation on the commercialization of HIF within the decade.
** May 23–26, Workshop for Accelerators for Heavy Ion Fusion at Lawrence Berkeley National Laboratory, presentation by Robert J. Burke on "Single Pass Heavy Ion Fusion". The Accelerator Working Group publishes recommendations supporting moving RF accelerator driven HIF toward commercialization.
** Stephen Slutz & Roger Vesey of Sandia National Labs publish a paper in Physical Review Letters presenting a computer simulation of the MagLIF concept showing it can produce high gain. According to the simulation, a 70 Mega Amp Z-pinch facility in combination with a Laser may be able to produce a spectacular energy return of 1000 times the expended energy. A 60 MA facility would produce a 100x yield.
** JET announces a major breakthrough in controlling instabilities in a fusion plasma. [http://phys.org/news/2012-01-closer-nuclear-fusion.html?=y One step closer to controlling nuclear fusion]
** In August Robert J. Burke presents updates to the SPRFD HIF process and Charles Helsley presents the Economics of SPRFD at the 19th International HIF Symposium at Berkeley, California. Industry was there in support of ion generation for SPRFD. The Fusion Power Corporation SPRFD patent is granted in Russia.
** China's EAST tokamak test reactor achieves a record confinement time of 30 seconds for plasma in the high-confinement mode (H-mode), thanks to improvements in heat dispersal from tokamak walls. This is an improvement of an order of magnitude with respect to state-of-the-art reactors.
** Construction of JT-60SA begins in January.
** US Scientists at NIF successfully generate more energy from fusion reactions than the energy absorbed by the nuclear fuel.
** Phoenix Nuclear Labs announces the sale of a high-yield neutron generator that could sustain 5×10 deuterium fusion reactions per second over a 24-hour period.
** On 9 October 2014, fusion research bodies from European Union member states and Switzerland signed an agreement to cement European collaboration on fusion research and EUROfusion, the European Consortium for the Development of Fusion Energy, was born.
** Germany conducts the first plasma discharge in Wendelstein 7-X, a large-scale stellarator capable of steady-state plasma confinement under fusion conditions.
** In January the polywell is presented at Microsoft Research.
** In August, MIT announces the ARC fusion reactor, a compact tokamak using rare-earth barium-copper oxide (REBCO) superconducting tapes to produce high-magnetic field coils that it claims produce comparable magnetic field strength in a smaller configuration than other designs.
** The Wendelstein 7-X produces the device's first hydrogen plasma.
** China's EAST tokamak test reactor achieves a stable 101.2-second steady-state high confinement plasma, setting a world record in long-pulse H-mode operation on the night of July 3.
** Helion Energy's fifth-generation plasma machine goes into operation, seeking to achieve plasma density of 20 Tesla and fusion temperatures.
** UK company Tokamak Energy's ST40 fusion reactor generates first plasma.
** TAE Technologies announces that the Norman reactor had achieved plasma.
** Energy corporation Eni announces a $50 million investment in start-up Commonwealth Fusion Systems, to commercialize ARC technology via the SPARC test reactor in collaboration with MIT.
** MIT scientists formulate a theoretical means to remove the excess heat from compact nuclear fusion reactors via larger and longer divertors.
** General Fusion begins developing a 70% scale demo system to be completed around 2023.
** TAE Technologies announces its reactor has reached a high temperature of nearly 20 million°C.
** The Fusion Industry Association founded as an initiative in 2018, is the unified voice of the fusion industry, working to transform the energy system with commercially viable fusion power.
** The United Kingdom announces a planned £200-million (US$248-million) investment to produce a design for the Spherical Tokamak for Energy Production (STEP) fusion facility around 2040. | 3 | Nuclear Fusion |
UV-sensitive syndrome is a cutaneous condition inherited in an autosomal recessive fashion, characterized by photosensitivity and solar lentigines. Recent research identified that mutations of the KIAA1530 (UVSSA) gene as cause for the development of UV-sensitive syndrome. Furthermore, this protein was identified as a new player in the Transcription-coupled repair (TC-NER). | 8 | Ultraviolet Radiation |
The triple-alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon. | 3 | Nuclear Fusion |
A major step was the work of Heinrich Heesch, who first rigorously established the concept of antisymmetry as part of a series of papers in 1929 and 1930. Applying this antisymmetry operation to the 32 crystallographic point groups gives a total of 122 magnetic point groups. However, although Heesch correctly laid out each of the magnetic point groups, his work remained obscure, and the point groups were later re-derived by Tavger and Zaitsev. The concept was more fully explored by Shubnikov in terms of color symmetry. When applied to space groups, the number increases from the usual 230 three dimensional space groups to 1651 magnetic space groups, as found in the 1953 thesis of Alexandr Zamorzaev. While the magnetic space groups were originally found using geometry, it was later shown the same magnetic space groups can be found using generating sets. | 7 | Magnetic Ordering |
Although it has not yet been commercialized for clinical use clinical studies have been done on intra- and extra-oral treatments with full-thickness engineered oral mucosa.
Full-thickness engineered oral mucosa is mainly used in maxillofacial reconstructive surgery and periodontal peri-implant reconstruction. Good clinical and histological results have been obtained. For example, there is vascular ingrowth and the transplanted keratinocytes integrate well into the native epithelium. Full-thickness engineered oral mucosa has also shown good results for extra-oral applications such as urethral reconstruction, ocular surface reconstruction and eyelid reconstruction. | 2 | Tissue Engineering |
Recent attempts have been made to relabel antifreeze proteins as ice structuring proteins to more accurately represent their function and to dispose of any assumed negative relation between AFPs and automotive antifreeze, ethylene glycol. These two things are completely separate entities, and show loose similarity only in their function. | 1 | Cryobiology |
Cooling catheters are inserted into a femoral vein. Cooled saline solution is circulated through either a metal coated tube or a balloon in the catheter. The saline cools the persons whole body by lowering the temperature of a persons blood. Catheters reduce temperature at rates ranging from per hour. Through the use of the control unit, catheters can bring body temperature to within of the target level. Furthermore, catheters can raise temperature at a steady rate, which helps to avoid harmful rises in intracranial pressure. A number of studies have demonstrated that targeted temperature management via catheter is safe and effective.
Adverse events associated with this invasive technique include bleeding, infection, vascular puncture, and deep vein thrombosis (DVT). Infection caused by cooling catheters is particularly harmful, as resuscitated people are highly vulnerable to the complications associated with infections. Bleeding represents a significant danger, due to a decreased clotting threshold caused by hypothermia. The risk of deep vein thrombosis may be the most pressing medical complication.
Deep vein thrombosis can be characterized as a medical event whereby a blood clot forms in a deep vein, usually the femoral vein. This condition may become potentially fatal if the clot travels to the lungs and causes a pulmonary embolism. Another potential problem with cooling catheters is the potential to block access to the femoral vein, which is a site normally used for a variety of other medical procedures, including angiography of the venous system and the right side of the heart. However, most cooling catheters are triple lumen catheters, and the majority of people post-arrest will require central venous access. Unlike non-invasive methods which can be administered by nurses, the insertion of cooling catheters must be performed by a physician fully trained and familiar with the procedure. The time delay between identifying a person who might benefit from the procedure and the arrival of an interventional radiologist or other physician to perform the insertion may minimize some of the benefit of invasive methods' more rapid cooling. | 1 | Cryobiology |
The term "hysteresis" is derived from , an Ancient Greek word meaning "deficiency" or "lagging behind". It was coined in 1881 by Sir James Alfred Ewing to describe the behaviour of magnetic materials.
Some early work on describing hysteresis in mechanical systems was performed by James Clerk Maxwell. Subsequently, hysteretic models have received significant attention in the works of Ferenc Preisach (Preisach model of hysteresis), Louis Néel and Douglas Hugh Everett in connection with magnetism and absorption. A more formal mathematical theory of systems with hysteresis was developed in the 1970s by a group of Russian mathematicians led by Mark Krasnosel'skii. | 7 | Magnetic Ordering |
Often, some amount of hysteresis is intentionally added to an electronic circuit to prevent unwanted rapid switching. This and similar techniques are used to compensate for contact bounce in switches, or noise in an electrical signal.
A Schmitt trigger is a simple electronic circuit that exhibits this property.
A latching relay uses a solenoid to actuate a ratcheting mechanism that keeps the relay closed even if power to the relay is terminated.
Some positive feedback from the output to one input of a comparator can increase the natural hysteresis (a function of its gain) it exhibits.
Hysteresis is essential to the workings of some memristors (circuit components which "remember" changes in the current passing through them by changing their resistance).
Hysteresis can be used when connecting arrays of elements such as nanoelectronics, electrochrome cells and memory effect devices using passive matrix addressing. Shortcuts are made between adjacent components (see crosstalk) and the hysteresis helps to keep the components in a particular state while the other components change states. Thus, all rows can be addressed at the same time instead of individually.
In the field of audio electronics, a noise gate often implements hysteresis intentionally to prevent the gate from "chattering" when signals close to its threshold are applied. | 7 | Magnetic Ordering |
United States Navy researchers at the Space and Naval Warfare Systems Center (SPAWAR) in San Diego have been studying cold fusion since 1989. In 2002 they released a two-volume report, "Thermal and nuclear aspects of the Pd/DO system", with a plea for funding. This and other published papers prompted a 2004 Department of Energy (DOE) review. | 3 | Nuclear Fusion |
The theory of bubble dynamics was started in 1917 by Lord Rayleigh during his work with the Royal Navy to investigate cavitation damage on ship propellers. Over several decades his work was refined and developed by Milton Plesset, Andrea Prosperetti, and others. The Rayleigh–Plesset equation is:
where is the bubble radius, is the second order derivative of the bubble radius with respect to time, is the first order derivative of the bubble radius with respect to time, is the density of the liquid, is the pressure in the gas (which is assumed to be uniform), is the background static pressure, is the sinusoidal driving pressure, is the viscosity of the liquid, and is the surface tension of the gas-liquid interface. | 0 | Luminescence |
Protein skimming removes certain organic compounds, including proteins and amino acids found in food particles and fish waste, by using the polarity of the protein itself. Due to their intrinsic charge, water-borne proteins are either repelled or attracted by the air/water interface and these molecules can be described as hydrophobic (such as fats or oils) or hydrophilic (such as salt, sugar, ammonia, most amino acids, and most inorganic compounds). However, some larger organic molecules can have both hydrophobic and hydrophilic portions. These molecules are called amphipathic or amphiphilic. Commercial protein skimmers work by generating a large air/water interface, specifically by injecting large numbers of bubbles into the water column. In general, the smaller the bubbles the more effective the protein skimming is because the surface area of small bubbles occupying the same volume is much greater than the same volume of larger bubbles. Large numbers of small bubbles present an enormous air/water interface for hydrophobic organic molecules and amphipathic organic molecules to collect on the bubble surface (the air/water interface). Water movement hastens diffusion of organic molecules, which effectively brings more organic molecules to the air/water interface and lets the organic molecules accumulate on the surface of the air bubbles. This process continues until the interface is saturated, unless the bubble is removed from the water or it bursts, in which case the accumulated molecules release back into the water column. However, it is important to note that further exposure of a saturated air bubble to organic molecules may continue to result in changes as compounds that bind more strongly may replace those molecules with a weaker binding that have already accumulated on the interface. Although some aquarists believe that increasing the contact time (or dwell time as it is sometimes called) is always good, it is incorrect to claim that it is always better to increase the contact time between bubbles and the aquarium water. As the bubbles increase near the top of the protein skimmer water column, they become denser and the water begins to drain and create the foam that will carry the organic molecules to the skimmate collection cup or to a separate skimmate waste collector and the organic molecules, and any inorganic molecules that may have become bound to the organic molecules, will be exported from the water system.
In addition to the proteins removed by skimming, there are a number of other organic and inorganic molecules that are typically removed. These include a variety of fats, fatty acids, carbohydrates, metals such as copper, and trace elements such as iodine. Particulates, phytoplankton, bacteria, and detritus are also removed; this is desired by some aquarists, and is often enhanced by placement of the skimmer before other forms of filtration, lessening the burden on the filtration system as a whole. There is at least one published study that provides a detailed list of the export products removed by the skimmer. Aquarists who keep filter-feeding invertebrates, however, sometimes prefer to keep these particulates in the water to serve as natural food.
Protein skimmers are used to harvest algae and phytoplankton gently enough to maintain viability for culturing or commercial sale as live cultures.
Alternative forms of water filtration have recently come into use, including the algae scrubber, which leaves food particles in the water for corals and small fish to consume, but removes the noxious compounds including ammonia, nitrite, nitrate, and phosphate that protein skimmers do not remove. | 5 | Separation Processes |
A strong acid is an acid that dissociates according to the reaction
where S represents a solvent molecule, such as a molecule of water or dimethyl sulfoxide (DMSO), to such an extent that the concentration of the undissociated species is too low to be measured. For practical purposes a strong acid can be said to be completely dissociated. An example of a strong acid is hydrochloric acid.
:(in aqueous solution)
Any acid with a value which is less than about -2 is classed as a strong acid. This results from the very high buffer capacity of solutions with a pH value of 1 or less and is known as the leveling effect.
The following are strong acids in aqueous and dimethyl sulfoxide solution. The values of , cannot be measured experimentally. The values in the following table are average values from as many as 8 different theoretical calculations.
Also, in water
* Nitric acid = −1.6
* Sulfuric acid (first dissociation only, ≈ −3)
The following can be used as protonators in organic chemistry
* Fluoroantimonic acid
* Magic acid
* Carborane superacid
* Fluorosulfuric acid ( = −6.4)
Sulfonic acids, such as p-toluenesulfonic acid (tosylic acid) are a class of strong organic oxyacids. Some sulfonic acids can be isolated as solids. Polystyrene functionalized into polystyrene sulfonate is an example of a substance that is a solid strong acid. | 4 | Acids + Bases |
Mixtures similar to Undark, consisting of radium and zinc sulfide were used by other companies. Trade names include:
* Luna, used by the Radium Dial Company, a division of Standard Chemical Company
and
* Marvelite, used by Cold Light Manufacturing Company (a subsidiary of the Radium Company of Colorado) | 0 | Luminescence |
In condensed matter physics, a spin glass is a magnetic state characterized by randomness, besides cooperative behavior in freezing of spins at a temperature called "freezing temperature" T. In ferromagnetic solids, component atoms' magnetic spins all align in the same direction. Spin glass when contrasted with a ferromagnet is defined as "disordered" magnetic state in which spins are aligned randomly or without a regular pattern and the couplings too are random.
The term "glass" comes from an analogy between the magnetic disorder in a spin glass and the positional disorder of a conventional, chemical glass, e.g., a window glass. In window glass or any amorphous solid the atomic bond structure is highly irregular; in contrast, a crystal has a uniform pattern of atomic bonds. In ferromagnetic solids, magnetic spins all align in the same direction; this is analogous to a crystal's lattice-based structure.
The individual atomic bonds in a spin glass are a mixture of roughly equal numbers of ferromagnetic bonds (where neighbors have the same orientation) and antiferromagnetic bonds (where neighbors have exactly the opposite orientation: north and south poles are flipped 180 degrees). These patterns of aligned and misaligned atomic magnets create what are known as frustrated interactions distortions in the geometry of atomic bonds compared to what would be seen in a regular, fully aligned solid. They may also create situations where more than one geometric arrangement of atoms is stable.
Spin glasses and the complex internal structures that arise within them are termed "metastable" because they are "stuck" in stable configurations other than the lowest-energy configuration (which would be aligned and ferromagnetic). The mathematical complexity of these structures is difficult but fruitful to study experimentally or in simulations; with applications to physics, chemistry, materials science and artificial neural networks in computer science. | 7 | Magnetic Ordering |
Nuclear fusion is normally understood to occur at temperatures in the tens of millions of degrees. This is called "thermonuclear fusion". Since the 1920s, there has been speculation that nuclear fusion might be possible at much lower temperatures by catalytically fusing hydrogen absorbed in a metal catalyst. In 1989, a claim by Stanley Pons and Martin Fleischmann (then one of the world's leading electrochemists) that such cold fusion had been observed caused a brief media sensation before the majority of scientists criticized their claim as incorrect after many found they could not replicate the excess heat. Since the initial announcement, cold fusion research has continued by a small community of researchers who believe that such reactions happen and hope to gain wider recognition for their experimental evidence. | 3 | Nuclear Fusion |
** Ernest Rutherford's Cavendish Laboratory at Cambridge University begins nuclear experiments with a particle accelerator built by John Cockcroft and Ernest Walton.
** In April, Walton produces the first man-made fission by using protons from the accelerator to split lithium into alpha particles.
** Using an updated version of the equipment firing deuterium rather than hydrogen, Mark Oliphant discovered helium-3 and tritium, and that heavy hydrogen nuclei could be made to react with each other. This is the first direct demonstration of fusion in the lab.
** Kantrowitz and Jacobs of the NACA Langley Research Center built a toroidal magnetic bottle and heat the plasma with a 150 W radio source. Hoping to heat the plasma to millions of degrees, the system fails and they are forced to abandon their Diffusion Inhibitor. This is the first attempt to make a working fusion reactor.
** Peter Thonemann develops a detailed plan for a pinch device, but is told to do other work for his thesis.
** Hans Bethe provides detailed calculations of the proton–proton chain reaction that powers stars. This work results in a Nobel Prize for Physics. | 3 | Nuclear Fusion |
Nanoscience and nanotechnology have been emerging as a technology for the development of various hybrid and composite materials for biomedical applications. When nanomaterials are used for the development of the composites in biology, they are called bionanocomposites. Bionanocomposites have been used in tissue engineering to replace, support, or regenerate the cells, organs, or parts of human entity such that it can function as normal.
Amylopectin-based bionanocomposites are another important class of bionanomaterials, which are biodegradable, with higher mechanical properties, optical transparency, thermal stability, and barrier properties than thermoplastic starch. In conjunction with other nanomaterials like cellulose nanocrystals, nano-ZnO, nanoclay, biodegradable synthetic polymers, starch is one of the most popular materials for the preparation of bionanocomposites for various biomedical applications such as controlled drug release, scaffold for tissue engineering, and cement for bone regeneration. Amylopectin is usually combined with a synthetic polymer with higher elastic modulus and yield strength. This allows for starch to withstand the higher fluid flow and mechanical forces prevalent in bone, cardiac, and endothelial tissue. | 6 | Carbohydrates |
In a traditional solid-state semiconductor, a solar cell is made from two doped crystals, one doped with n-type impurities (n-type semiconductor), which add additional free conduction band electrons, and the other doped with p-type impurities (p-type semiconductor), which add additional electron holes. When placed in contact, some of the electrons in the n-type portion flow into the p-type to "fill in" the missing electrons, also known as electron holes. Eventually enough electrons will flow across the boundary to equalize the Fermi levels of the two materials. The result is a region at the interface, the p–n junction, where charge carriers are depleted and/or accumulated on each side of the interface. In silicon, this transfer of electrons produces a potential barrier of about 0.6 to 0.7 eV.
When placed in the sun, photons of the sunlight can excite electrons on the p-type side of the semiconductor, a process known as photoexcitation. In silicon, sunlight can provide enough energy to push an electron out of the lower-energy valence band into the higher-energy conduction band. As the name implies, electrons in the conduction band are free to move about the silicon. When a load is placed across the cell as a whole, these electrons will flow out of the p-type side into the n-type side, lose energy while moving through the external circuit, and then flow back into the p-type material where they can once again re-combine with the valence-band hole they left behind. In this way, sunlight creates an electric current.
In any semiconductor, the band gap means that only photons with that amount of energy, or more, will contribute to producing a current. In the case of silicon, the majority of visible light from red to violet has sufficient energy to make this happen. Unfortunately higher energy photons, those at the blue and violet end of the spectrum, have more than enough energy to cross the band gap; although some of this extra energy is transferred into the electrons, the majority of it is wasted as heat. Another issue is that in order to have a reasonable chance of capturing a photon, the n-type layer has to be fairly thick. This also increases the chance that a freshly ejected electron will meet up with a previously created hole in the material before reaching the p–n junction. These effects produce an upper limit on the efficiency of silicon solar cells, currently around 20% for common modules and up to 27.1% for the best laboratory cells (33.16% is the theoretical maximum efficiency for single band gap solar cells, see Shockley–Queisser limit.).
By far the biggest problem with the conventional approach is cost; solar cells require a relatively thick layer of doped silicon in order to have reasonable photon capture rates, and silicon processing is expensive. There have been a number of different approaches to reduce this cost over the last decade, notably the thin-film approaches, but to date they have seen limited application due to a variety of practical problems. Another line of research has been to dramatically improve efficiency through the multi-junction approach, although these cells are very high cost and suitable only for large commercial deployments. In general terms the types of cells suitable for rooftop deployment have not changed significantly in efficiency, although costs have dropped somewhat due to increased supply. | 8 | Ultraviolet Radiation |
Around the world, household drinking water purification systems, including a RO step, are commonly used for improving water for drinking and cooking.
Such systems typically include these steps:
* a sediment filter to trap particles, including rust and calcium carbonate
* a second sediment filter with smaller pores
* an activated carbon filter to trap organic chemicals and chlorine, which degrades certain types of thin-film composite membrane
* an RO thin-film composite membrane
* an ultraviolet lamp for sterilizing any microbes that survive RO
* a second carbon filter to capture chemicals that survive RO
In some systems, the carbon prefilter is replaced by a cellulose triacetate (CTA) membrane. CTA is a paper by-product membrane bonded to a synthetic layer that allows contact with chlorine in the water. These require a small amount of chlorine in the water source to prevent bacteria from forming on it. The typical rejection rate for CTA membranes is 85–95%.
The cellulose triacetate membrane rots unless protected by chlorinated water, while the thin-film composite membrane breaks down in the presence of chlorine. The thin-film composite (TFC) membrane is made of synthetic material, and requires the chlorine to be removed before the water enters the membrane. To protect the TFC membrane elements from chlorine damage, carbon filters are used as pre-treatment. TFC membranes have a higher rejection rate of 95–98% and a longer life than CTA membranes.
Portable RO water processors are sold for personal water available. To work effectively, the water feeding to these units should be under pressure (typically 280 kPa (40 psi) or greater). These processors can be used in areas lacking clean water.
US mineral water production uses RO. In Europe such processing of natural mineral water (as defined by a European directive) is not allowed. In practice, a fraction of the living bacteria pass through RO through membrane imperfections or bypass the membrane entirely through leaks in seals.
For household purification absent the need to remove dissolved minerals (soften the water), the alternative to RO is an activated carbon filter with a microfiltration membrane. | 5 | Separation Processes |
Protein phosphatase 1 subunits PP1β and PP1γ have been shown to form functional complexes with OGT. A synthetic phosphopeptide was able to be dephosphorylated and O-GlcNAcylated by an OGT immunoprecipitate. This complex has been referred to as a "yin-yang complex" as it replaces a phosphate modification with an O-GlcNAc modification.
MYPT1 is another protein phosphatase subunit that forms complexes with OGT and is itself O-GlcNAcylated. MYPT1 appears to have a role in directing OGT towards specific substrates. | 6 | Carbohydrates |
Economic systems can exhibit hysteresis. For example, export performance is subject to strong hysteresis effects: because of the fixed transportation costs it may take a big push to start a country's exports, but once the transition is made, not much may be required to keep them going.
When some negative shock reduces employment in a company or industry, fewer employed workers then remain. As usually the employed workers have the power to set wages, their reduced number incentivizes them to bargain for even higher wages when the economy again gets better instead of letting the wage be at the equilibrium wage level, where the supply and demand of workers would match. This causes hysteresis: the unemployment becomes permanently higher after negative shocks. | 7 | Magnetic Ordering |
After clearing and labeling, tissues are typically imaged using confocal microscopy, two-photon microscopy, or one of the many variants of light-sheet fluorescence microscopy. Other less commonly used methods include optical projection tomography and stimulated Raman scattering. | 2 | Tissue Engineering |
Electrons and nuclei are kept together by electrostatic attraction (negative attracts positive). Furthermore, electrons are sometimes shared by neighboring atoms or transferred to them (by processes of quantum physics); this link between atoms is referred to as a chemical bond and is responsible for the formation of all chemical compounds.
The electric force does not hold nuclei together, because all protons carry a positive charge and repel each other. If two protons were touching, their repulsion force would be almost 40 Newton. Because each of the neutrons carries total charge zero, a proton could electrically attract a neutron if the proton could induce the neutron to become electrically polarized. However, having the neutron between two protons (so their mutual repulsion decreases to 10 N) would attract the neutron only for an electric quadrupole arrangement. Higher multipoles, needed to satisfy more protons, cause weaker attraction, and quickly become implausible.
After the proton and neutron magnetic moments were measured and verified, it was apparent that their magnetic forces might be 20 or 30 newtons, attractive if properly oriented. A pair of protons would do 10 joules of work to each other as they approach – that is, they would need to release energy of 0.5 MeV in order to stick together. On the other hand, once a pair of nucleons magnetically stick, their external fields are greatly reduced, so it is difficult for many nucleons to accumulate much magnetic energy.
Therefore, another force, called the nuclear force (or residual strong force) holds the nucleons of nuclei together. This force is a residuum of the strong interaction, which binds quarks into nucleons at an even smaller level of distance.
The fact that nuclei do not clump together (fuse) under normal conditions suggests that the nuclear force must be weaker than the electric repulsion at larger distances, but stronger at close range. Therefore, it has short-range characteristics. An analogy to the nuclear force is the force between two small magnets: magnets are very difficult to separate when stuck together, but once pulled a short distance apart, the force between them drops almost to zero.
Unlike gravity or electrical forces, the nuclear force is effective only at very short distances. At greater distances, the electrostatic force dominates: the protons repel each other because they are positively charged, and like charges repel. For that reason, the protons forming the nuclei of ordinary hydrogen—for instance, in a balloon filled with hydrogen—do not combine to form helium (a process that also would require some protons to combine with electrons and become neutrons). They cannot get close enough for the nuclear force, which attracts them to each other, to become important. Only under conditions of extreme pressure and temperature (for example, within the core of a star), can such a process take place. | 3 | Nuclear Fusion |
In the early 1950s, Oak Ridge National Laboratory was composed of a small group of scientists that were mostly experienced with research in ion-source technology. However, research from Project Sherwood was a growing area of interest, and the researchers at Oak Ridge National Laboratory wanted to participate in the discovery of controlled fusion. They studied areas of controlled fusion such as the rate of plasma diffusion in a magnetic field and the charge-exchange process. However, their work with ion-source was still a large part of their research. | 3 | Nuclear Fusion |
Hydroiodic acid is listed as a U.S. Federal DEA List I Chemical, owing to its use as a reducing agent related to the production of methamphetamine from ephedrine or pseudoephedrine (recovered from nasal decongestant pills). | 4 | Acids + Bases |
*Undark produced by the United States Radium Corporation
*Luna produced by the Radium Dial Company
*Marvelite produced by the Cold Light Manufacturing Company (a subsidiary of the Radium Company of Colorado) | 0 | Luminescence |
Monosaccharides are the simplest carbohydrates in that they cannot be hydrolyzed to smaller carbohydrates. They are aldehydes or ketones with two or more hydroxyl groups. The general chemical formula of an unmodified monosaccharide is (C•HO), literally a "carbon hydrate". Monosaccharides are important fuel molecules as well as building blocks for nucleic acids. The smallest monosaccharides, for which n=3, are dihydroxyacetone and D- and L-glyceraldehydes. | 6 | Carbohydrates |
The Endocare PerCryo Percutaneous Cryoablation device utilizes argon as a coolant and can be used with four different single cryoprobe configurations with a diameter of either 1.7 mm (~16 gauge) or 2.4 mm (~13 gauge) in diameter .
The Myoscience Iovera is a handheld device that uses nitrous oxide as a coolant and can be used with a three-probe configuration with a probe diameter of 0.4 mm (~27 gauge). | 1 | Cryobiology |
A heterogeneous mixture (e. g. liquid and solid) can be separated by mechanical separation processes like filtration or centrifugation. Homogeneous mixtures can be separated by molecular separation processes; these are either equilibrium-based or rate-controlled. Equilibrium-based processes are operating by the formation of two immiscible phases with different compositions at equilibrium, an example is distillation (in distillation the vapor has another composition than the liquid). Rate-controlled processes are based on different transport rates of compounds through a medium, examples are adsorption, ion exchange or crystallization.
Separation of a mixture into two phases can be done by an energy separating agent, a mass separating agent, a barrier or external fields. Energy-separating agents are used for creating a second phase (immiscible of different composition than the first phase), they are the most common techniques used in industry. For example, leads the addition of heat (the separating agent) to a liquid (first phase) to the formation of vapor (second phase). Mass-separating agents are other chemicals. They selectively dissolve or absorb one of the products; they are either a liquid (for sorption, extractive distillation or extraction) or a solid (for adsorption or ion exchange). The use of a barrier which restricts the movement of one compound but not of the other one (semipermeable membranes) is less common; external fields are used just in special applications. | 5 | Separation Processes |
Indoor tanning involves using a device that emits ultraviolet radiation to produce a cosmetic tan. Typically found in tanning salons, gyms, spas, hotels, and sporting facilities, and less often in private residences, the most common device is a horizontal tanning bed, also known as a sunbed or solarium. Vertical devices are known as tanning booths or stand-up sunbeds.
First introduced in the 1960s, indoor tanning became popular with people in the Western world, particularly in Scandinavia, in the late 1970s. The practice finds a cultural parallel in skin whitening in Asian countries, and both support multibillion-dollar industries. Most indoor tanners are women, 16–25 years old, who want to improve their appearance or mood, acquire a pre-holiday tan, or treat a skin condition.
Across Australia, Canada, Northern Europe and the United States, 18.2% of adults, 45.2% of university students, and 22% of adolescents had tanned indoors in the previous year, according to studies in 2007–2012. As of 2010 the indoor-tanning industry employed 160,000 in the United States, where 10–30 million tanners visit 25,000 indoor facilities annually. In the United Kingdom, 5,350 tanning salons were in operation in 2009. From 1997 several countries and US states banned under-18s from indoor tanning. The commercial use of tanning beds was banned entirely in Brazil in 2009 and Australia in 2015. , thirteen U.S. states and one territory have banned under-18s from using them, and at least 42 states and the District of Columbia have imposed regulations, such as requiring parental consent.
Indoor tanning is a source of UV radiation, which is known to cause skin cancer, including melanoma and skin aging, and is associated with sunburn, photodrug reactions, infections, weakening of the immune system, and damage to the eyes, including cataracts, photokeratitis (snow blindness) and eye cancer. Injuries caused by tanning devices lead to over 3,000 emergency-room cases a year in the United States alone. Physicians may use or recommend tanning devices to treat skin conditions such as psoriasis, but the World Health Organization does not recommend their use for cosmetic purposes. The WHO's International Agency for Research on Cancer includes tanning devices, along with ultraviolet radiation from the sun, in its list of group 1 carcinogens. Researchers at the Yale School of Public Health found evidence of addiction to tanning in a 2017 paper. | 8 | Ultraviolet Radiation |
Suppose that a ferromagnet is single-domain in the strictest sense: the magnetization is uniform and rotates in unison. If the magnetic moment is and the volume of the particle is , the magnetization is , where is the saturation magnetization and are direction cosines (components of a unit vector) so . The energy associated with magnetic anisotropy can depend on the direction cosines in various ways, the most common of which are discussed below. | 7 | Magnetic Ordering |
The synthesis of glycogen in the liver following a fructose-containing meal proceeds from gluconeogenic precursors. Fructose is initially converted to DHAP and glyceraldehyde by fructokinase and aldolase B. The resultant glyceraldehyde then undergoes phosphorylation to glyceraldehyde-3-phosphate. Increased concentrations of DHAP and glyceraldehyde-3-phosphate in the liver drive the gluconeogenic pathway toward glucose-6-phosphate, glucose-1-phosphate and glycogen formation. It appears that fructose is a better substrate for glycogen synthesis than glucose and that glycogen replenishment takes precedence over triglyceride formation. Once liver glycogen is replenished, the intermediates of fructose metabolism are primarily directed toward triglyceride synthesis. | 6 | Carbohydrates |
Glucosinolates constitute a natural class of organic compounds that contain sulfur and nitrogen and are derived from glucose and an amino acid.
They are water-soluble anions and belong to the glucosides. Every glucosinolate contains a central carbon atom, which is bound to the sulfur atom of the thioglucose group, and via a nitrogen atom to a sulfate group (making a sulfated aldoxime). In addition, the central carbon is bound to a side group; different glucosinolates have different side groups, and it is variation in the side group that is responsible for the variation in the biological activities of these plant compounds.
The essence of glucosinolate chemistry is their ability to convert into an isothiocyanate (a "mustard oil") upon hydrolysis of the thioglucoside bond by the enzyme myrosinase.
The semisystematic naming of glucosinolates consists of the chemical name of the group "R" in the diagram followed by "glucosinolate", with or without a space. For example, allylglucosinolate and allyl glucosinolate refer to the same compound: both versions are found in the literature. Isothiocyanates are conventionally written as two words.
The following are some glucosinolates and their isothiocyanate products:
* Allylglucosinolate (sinigrin) is the precursor of allyl isothiocyanate
* Benzylglucosinolate (glucotropaeolin) is the precursor of benzyl isothiocyanate
* Phenethylglucosinolate (gluconasturtiin) is the precursor of phenethyl isothiocyanate
* (R)-4-(methylsulfinyl)butylglucosinolate (glucoraphanin) is the precursor of (R)-4-(methylsulfinyl)butyl isothiocyanate (sulforaphane)
* (R)-2-hydroxybut-3-enylglucosinolate (progoitrin) is probably the precursor of (S)-2-hydroxybut-3-enyl isothiocyanate, which is expected to be unstable and immediately cyclize to form (S)-5-vinyloxazolidine-2-thione (goitrin)
Sinigrin was first of the class to be isolated — in 1839 as its potassium salt. Its chemical structure had been established by 1930, showing that it is a glucose derivative with β--glucopyranose configuration. It was unclear at that time whether the C=N bond was in the Z (or syn) form, with sulfur and oxygen substituents on the same side of the double bond, or the alternative E form in which they are on opposite sides. The matter was settled by X-ray crystallography in 1963. It is now known that all natural glucosinolates are of Z form, although both forms can be made in the laboratory. The "ate" ending in the naming of these compounds implies that they are anions at physiological pH and an early name for this allylglucosinolate was potassium myronate. Care must be taken when discussing these compounds since some older publications do not make it clear whether they refer to the anion alone, its corresponding acid or the potassium salt. | 6 | Carbohydrates |
Localization of magnetic sources producing the SPMR fields is done by solving the inverse problem of electromagnetism. The forward electromagnetic problem consists of modeling the sources as magnetic dipoles for each magnetic source or more complex configurations that model each source as a distributed source. Examples of the latter are multiple models, Bayesian models, or distributed dipole models. The magnetic dipole model has the form
where r and p are the location and dipole moment vectors of the magnetic dipole, and is the magnetic permeability of free space.
For a subject containing N sources, a minimum of 4N measurements of the magnetic field are required to determine the coordinates and magnetic moment of each source. In the case where the particles have been aligned by the external magnetizing field in a particular orientation, 3N measurements are required to obtain solutions. This latter situation leads to increased accuracy for finding the locations of objects as fewer variables are required in the inverse solution algorithm. Increased number of measurements provides an over-determined solution, increasing the localization accuracy.
Solving the inverse problem for magnetic dipole or more complex models is performed with non-linear algorithms. The Levenberg-Marquardt algorithm is one approach to obtaining solutions to this non-linear problem. More complex methods are available from other biomagnetism programs.
Coordinates and magnetic moments, for each source assumed to be present in the sample, are determined from solution of the inverse problem. | 7 | Magnetic Ordering |
A risk of ovarian stimulation is the development of ovarian hyperstimulation syndrome, particularly if hCG is used for inducing final oocyte maturation. This results in swollen, painful ovaries. It occurs in 30% of patients. Mild cases can be treated with over the counter medications and cases can be resolved in the absence of pregnancy. In moderate cases, ovaries swell and fluid accumulated in the abdominal cavities and may have symptoms of heartburn, gas, nausea or loss of appetite. In severe cases, patients have sudden excess abdominal pain, nausea, vomiting and will result in hospitalisation.
During egg retrieval, there exists a small chance of bleeding, infection, and damage to surrounding structures such as bowel and bladder (transvaginal ultrasound aspiration) as well as difficulty in breathing, chest infection, allergic reactions to medication, or nerve damage (laparoscopy).
Ectopic pregnancy may also occur if a fertilised egg develops outside the uterus, usually in the fallopian tubes and requires immediate destruction of the foetus.
IVF does not seem to be associated with an elevated risk of cervical cancer, nor with ovarian cancer or endometrial cancer when neutralising the confounder of infertility itself. Nor does it seem to impart any increased risk for breast cancer.
Regardless of pregnancy result, IVF treatment is usually stressful for patients. Neuroticism and the use of escapist coping strategies are associated with a higher degree of distress, while the presence of social support has a relieving effect. A negative pregnancy test after IVF is associated with an increased risk for depression, but not with any increased risk of developing anxiety disorders. Pregnancy test results do not seem to be a risk factor for depression or anxiety among men when the relationships is between two cisgender, heterosexual people. Hormonal agents such as gonadotropin-releasing hormone agonist (GnRH agonist) are associated with depression.
Studies show that there is an increased risk of venous thrombosis or pulmonary embolism during the first trimester of IVF. When looking at long-term studies comparing patients who received or did not receive IVF, there seems to be no correlation with increased risk of cardiac events. There are more ongoing studies to solidify this.
Spontaneous pregnancy has occurred after successful and unsuccessful IVF treatments. Within 2 years of delivering an infant conceived through IVF, subfertile patients had a conception rate of 18%. | 1 | Cryobiology |
Weerman degradation, also named Weerman reaction, is a name reaction in organic chemistry. It is named after Rudolf Adrian Weerman, who discovered it in 1910. In general, it is an organic reaction in carbohydrate chemistry in which amides are degraded by sodium hypochlorite, forming an aldehyde with one less carbon. Some have regarded it as an extension of the Hofmann rearrangement. | 6 | Carbohydrates |
Applications in biotechnology were developed only most recently. This is due to the sensitivity of bioproducts such as proteins towards organic extractants.
One approach by C. van den Berg et al. focuses on the use of impregnated particles for in situ recovery of phenol from Pseudomonas putida fermentations using ionic liquids. Further development led to the use of high capacity polysulfone capsules. These capsules are basically hollow particles surrounded by a membrane. The interior is completely filled with extractant and thus increases the impregnation capacity as compared to classical SIRs.
A completely new approach of using SIRs for the separation or purification of biotechnological products such as proteins is based on the concept of impregnating porous particles with aqueous polymer solutions developed by B. Burghoff. These so-called Tunable Aqueous Polymer-Phase Impregnated Resins (TAPPIR) enhance aqueous two-phase extraction (ATPE) by applying the SIR technology. During classical aqueous two-phase extraction, biotechnological components such as proteins are extracted from aqueous solutions by using a second aqueous phase. This second aqueous phase contains e.g. polyethylene glycol (PEG). On the one hand, a low density difference and low interfacial tension between the two aqueous phases facilitate comparatively fast mass transfer between the phases. On the other hand, PEG appears to stabilize the protein molecules, which results in a comparatively low protein denaturation during the extraction. However, a significant drawback of ATPE is the persistent emulsification, which makes phase separation a challenge. The idea behind TAPPIR is to use the advantages posed by SIRs, namely low extractant loss due to immobilization in the pores and less emulsification than in liquid-liquid extraction. This way, the drawbacks of ATPE could be remedied. The setup would consist of a packed column or a fluidized bed rather than liquid-liquid extraction equipment with additional phase separation steps. Nonetheless, as yet only first feasibility studies are on the way to prove the concept. Adrawback of this method is the non-conitnous working mode. The packed column is run similar as a chromatographic column. | 5 | Separation Processes |
In condensed matter physics, the term geometrical frustration (or in short: frustration) refers to a phenomenon where atoms tend to stick to non-trivial positions or where, on a regular crystal lattice, conflicting inter-atomic forces (each one favoring rather simple, but different structures) lead to quite complex structures. As a consequence of the frustration in the geometry or in the forces, a plenitude of distinct ground states may result at zero temperature, and usual thermal ordering may be suppressed at higher temperatures. Much studied examples are amorphous materials, glasses, or dilute magnets.
The term frustration, in the context of magnetic systems, has been introduced by Gerard Toulouse in 1977. Frustrated magnetic systems had been studied even before. Early work includes a study of the Ising model on a triangular lattice with nearest-neighbor spins coupled antiferromagnetically, by G. H. Wannier, published in 1950. Related features occur in magnets with competing interactions, where both ferromagnetic as well as antiferromagnetic couplings between pairs of spins or magnetic moments are present, with the type of interaction depending on the separation distance of the spins. In that case commensurability, such as helical spin arrangements may result, as had been discussed originally, especially, by A. Yoshimori, T. A. Kaplan, R. J. Elliott, and others, starting in 1959, to describe experimental findings on rare-earth metals. A renewed interest in such spin systems with frustrated or competing interactions arose about two decades later, beginning in the 1970s, in the context of spin glasses and spatially modulated magnetic superstructures. In spin glasses, frustration is augmented by stochastic disorder in the interactions, as may occur experimentally in non-stoichiometric magnetic alloys. Carefully analyzed spin models with frustration include the Sherrington–Kirkpatrick model, describing spin glasses, and the ANNNI model, describing commensurability magnetic superstructures. Recently, the concept of frustration has been used in brain network analysis to identify the non-trivial assemblage of neural connections and highlight the adjustable elements of the brain. | 7 | Magnetic Ordering |
In vitro fertilisation (IVF) is a process of fertilisation where an egg is combined with sperm in vitro ("in glass"). The process involves monitoring and stimulating a womans ovulatory process, removing an ovum or ova (egg or eggs) from their ovaries and letting a mans sperm fertilise them in a culture medium in a laboratory. After the fertilised egg (zygote) undergoes embryo culture for 2–6 days, it is transferred by catheter into the uterus, with the intention of establishing a successful pregnancy.
IVF is a type of assisted reproductive technology used for infertility treatment, gestational surrogacy, and, in combination with pre-implantation genetic testing, avoiding transmission of genetic conditions. A fertilised egg from a donor may implant into a surrogate's uterus, and the resulting child is genetically unrelated to the surrogate. Some countries have banned or otherwise regulate the availability of IVF treatment, giving rise to fertility tourism. Restrictions on the availability of IVF include costs and age, in order for a person to carry a healthy pregnancy to term. Children born through IVF are colloquially called test tube babies.
In July 1978, Louise Brown was the first child successfully born after her mother received IVF treatment. Brown was born as a result of natural-cycle IVF, where no stimulation was made. The procedure took place at Dr Kershaws Cottage Hospital (now Dr Kershaws Hospice) in Royton, Oldham, England. Robert Edwards was awarded the Nobel Prize in Physiology or Medicine in 2010. The physiologist co-developed the treatment together with Patrick Steptoe and embryologist Jean Purdy but the latter two were not eligible for consideration as they had died and the Nobel Prize is not awarded posthumously.
Assisted by egg donation and IVF, there are many women who may be past their reproductive years, have infertile partners, have idiopathic female-fertility issues, or have reached menopause, that can still become pregnant. After the IVF treatment, some couples get pregnant without any fertility treatments. In 2023, it was estimated that twelve million children had been born worldwide using IVF and other assisted reproduction techniques. A 2019 study that explores 10 adjuncts with IVF (screening hysteroscopy, DHEA, testosterone, GH, aspirin, heparin, antioxidants, seminal plasma and PRP) suggests that until more evidence is done to show that these adjuncts are safe and effective, they should be avoided. | 1 | Cryobiology |
Zenobi-Wong completed her undergraduate degree in mechanical engineering at the Massachusetts Institute of Technology, and a graduate degree at Stanford University. She completed her PhD on the role of mechanical forces in skeletal development in 1990. After this, she first worked for a year as a postdoc in the Orthopaedic Research Laboratories, University of Michigan, before moving to the University of Bern as group leader Cartilage Biomechanics in 1992, where she habilitated in 2000. In 2003, she moved to ETH Zürich, first to the Institute for Biomedical Engineering, and later to the Department of Health Sciences and Technology, where she became an associate professor in 2017. | 2 | Tissue Engineering |
Muon-catalyzed fusion is a fusion process that occurs at ordinary temperatures. It was studied in detail by Steven Jones in the early 1980s. Net energy production from this reaction has been unsuccessful because of the high energy required to create muons, their short 2.2 µs half-life, and the high chance that a muon will bind to the new alpha particle and thus stop catalyzing fusion. | 3 | Nuclear Fusion |
Medium-pressure mercury-vapor lamps have historically been the industry standard for curing products with ultraviolet light. The bulbs work by sending an electric discharge to excite a mixture of mercury and noble gases, generating a plasma. Once the mercury reaches a plasma state, it irradiates a high spectral output in the UV region of the electromagnetic spectrum. Major peaks in light intensity occur in the 240-270 nm and 350-380 nm regions. These intense peaks, when matched with the absorption profile of a photoinitiator, cause the rapid curing of materials. By modifying the bulb mixture with different gases and metal halides, the distribution of wavelength peaks can be altered, and material interactions are changed.
Medium-pressure lamps can either be standard gas-discharge lamps or electrodeless lamps, and typically use an elongated bulb to emit energy. By incorporating optical designs such an elliptical or even aconic reflector, light can either be focused or projected over a far distance. These lamps can often operate at over 900 degrees Celsius and produce UV energy levels over 10 W/cm. | 8 | Ultraviolet Radiation |
An absorption or release of nuclear energy occurs in nuclear reactions or radioactive decay; those that absorb energy are called endothermic reactions and those that release energy are exothermic reactions. Energy is consumed or released because of differences in the nuclear binding energy between the incoming and outgoing products of the nuclear transmutation.
The best-known classes of exothermic nuclear transmutations are nuclear fission and nuclear fusion. Nuclear energy may be released by fission, when heavy atomic nuclei (like uranium and plutonium) are broken apart into lighter nuclei. The energy from fission is used to generate electric power in hundreds of locations worldwide. Nuclear energy is also released during fusion, when light nuclei like hydrogen are combined to form heavier nuclei such as helium. The Sun and other stars use nuclear fusion to generate thermal energy which is later radiated from the surface, a type of stellar nucleosynthesis. In any exothermic nuclear process, nuclear mass might ultimately be converted to thermal energy, emitted as heat.
In order to quantify the energy released or absorbed in any nuclear transmutation, one must know the nuclear binding energies of the nuclear components involved in the transmutation. | 3 | Nuclear Fusion |
Biological scaffolds can be created from human donor tissue or from animals; however, animal tissue is often more popular since it is more widely accessible and more plentiful. Xenograft, from a donor of a different species from the recipient, heart valves can be from either pigs, cows, or sheep. If either human or animal tissue is used, the first step in creating useful scaffolds is decellularization, which means to remove the cellular contents all the while preserving the ECM matrix, which is advantageous compared to manufacturing synthetic scaffolds from scratch. Many decellularization methods have been used such as the use of nonionic and ionic detergents that disrupt cellular material interactions or the use of enzymes to cleave peptide bonds, RNA, and DNA. | 2 | Tissue Engineering |
The energy density for a tetragonal crystal is
Note that the term, the one that determines the basal plane anisotropy, is fourth order (same as the term). The definition of may vary by a constant multiple between publications.
The energy density for a rhombohedral crystal is | 7 | Magnetic Ordering |
A magnetic particle with triaxial anisotropy still has a single easy axis, but it also has a hard axis (direction of maximum energy) and an intermediate axis (direction associated with a saddle point in the energy). The coordinates can be chosen so the energy has the form
If the easy axis is the direction, the intermediate axis is the direction and the hard axis is the direction. | 7 | Magnetic Ordering |
Thomson's experiments are an example of AMR, a property of a material in which a dependence of electrical resistance on the angle between the direction of electric current and direction of magnetization is observed. The effect arises in most cases from the simultaneous action of magnetization and spin-orbit interaction (exceptions related to non-collinear magnetic order notwithstanding, see Sec. 4(b) in the review ) and its detailed mechanism depends on the material. It can be for example due to a larger probability of s-d scattering of electrons in the direction of magnetization (which is controlled by the applied magnetic field). The net effect (in most materials) is that the electrical resistance has maximum value when the direction of current is parallel to the applied magnetic field. AMR of new materials is being investigated and magnitudes up to 50% have been observed in some uranium (but otherwise quite conventional) ferromagnetic compounds. Very recently, materials with extreme AMR have been identified driven by unconventional mechanisms such as a metal-insulator transition triggered by rotating the magnetic moments (while for some directions of magnetic moments, the system is semimetallic, for other directions a gap opens).
In polycrystalline ferromagnetic materials, the AMR can only depend on the angle between the magnetization and current direction
and (as long as the resistivity of the material can be described by a rank-two tensor), it must follow
where is the (longitudinal) resistivity of the film and are the resistivities for and , respectively. Associated with longitudinal resistivity, there is also transversal resistivity dubbed (somewhat confusingly[1]) the planar Hall effect. In monocrystals, resistivity depends also on individually.
To compensate for the non-linear characteristics and inability to detect the polarity of a magnetic field, the following structure is used for sensors. It consists of stripes of aluminum or gold placed on a thin film of permalloy (a ferromagnetic material exhibiting the AMR effect) inclined at an angle of 45°. This structure forces the current not to flow along the “easy axes” of thin film, but at an angle of 45°. The dependence of resistance now has a permanent offset which is linear around the null point. Because of its appearance, this sensor type is called barber pole.
The AMR effect is used in a wide array of sensors for measurement of Earth's magnetic field (electronic compass), for electric current measuring (by measuring the magnetic field created around the conductor), for traffic detection and for linear position and angle sensing. The biggest AMR sensor manufacturers are Honeywell, NXP Semiconductors, STMicroelectronics, and [http://www.sensitec.com Sensitec GmbH].
As theoretical aspects, I. A. Campbell, A. Fert, and O. Jaoul (CFJ) derived an expression of the AMR ratio for Ni-based alloys using the two-current model with s-s and s-d scattering processes, where s is a conduction electron and d is 3d states with the spin-orbit interaction. The AMR ratio is expressed as
with and , where , , and are a spin-orbit coupling constant (so-called ), an exchange field, and a resistivity for spin , respectively. In addition, recently, Satoshi Kokado et al. have obtained the general expression of the AMR ratio for 3d transition-metal ferromagnets by extending the CFJ theory to a more general one. The general expression can also be applied to half-metals. | 7 | Magnetic Ordering |
Medical devices are classified by the US Food and Drug Administration (FDA) under three different classes depending on the risks the medical device may impose on the user. According to 21CFR 860.3, Class I devices are considered to pose the least amount of risk to the user and require the least amount of control. Class I devices include simple devices such as arm slings and hand-held surgical instruments. Class II devices are considered to need more regulation than Class I devices and are required to undergo specific requirements before FDA approval. Class II devices include X-ray systems and physiological monitors. Class III devices require the most regulatory controls since the device supports or sustains human life or may not be well tested. Class III devices include replacement heart valves and implanted cerebellar stimulators. Many implants typically fall under Class II and Class III devices. | 2 | Tissue Engineering |
All pregnancies can be risky, but there are greater risk for birthing parents who are older and are over the age of 40. As people get older, they are more likely to develop conditions such as gestational diabetes and pre-eclampsia. If the birthing parent does conceive over the age of 40, their offspring may be of lower birth weight, and more likely to requires intensive care. Because of this, the increased risk is a sufficient cause for concern. The high incidence of caesarean in older patients is commonly regarded as a risk.
Those conceiving at 40 have a greater risk of gestational hypertension and premature birth. The offspring is at risk when being born from older mothers, and the risks associated with being conceived through IVF.
Adriana Iliescu held the record for a while as the oldest woman to give birth using IVF and a donor egg, when she gave birth in 2004 at the age of 66. In September 2019, a 74-year-old woman became the oldest-ever to give birth after she delivered twins at a hospital in Guntur, Andhra Pradesh. | 1 | Cryobiology |
EuroCarbDB was an EU-funded initiative for the creation of software and standards for the systematic collection of carbohydrate structures and their experimental data, which was discontinued in 2010 due to lack of funding. The project included a database of known carbohydrate structures and experimental data, specifically mass spectrometry, HPLC and NMR data, accessed via a web interface that provides for browsing, searching and contribution of structures and data to the database. The project also produces a number of associated bioinformatics tools for carbohydrate researchers:
* GlycanBuilder, a Java applet for drawing glycan structures
* GlycoWorkbench, a standalone Java application for semi-automated analysis and annotation of glycan mass spectra
* GlycoPeakfinder, a webapp for calculating glycan compositions from mass data
The canonical online version of EuroCarbDB was hosted by the European Bioinformatics Institute at www.ebi.ac.uk up to 2012, and then relax.organ.su.se.
EuroCarb code has since been incorporated into and extended by UniCarb-DB, which also includes the work of the defunct GlycoSuite database. | 6 | Carbohydrates |
Akin to ordinary ink printers, bioprinters have three major components to them. These are the hardware used, the type of bio-ink, and the material it is printed on (biomaterials). Bio-ink is a material made from living cells that behaves much like a liquid, allowing people to print it in order to create the desired shape. To make bio-ink, scientists create a slurry of cells that can be loaded into a cartridge and inserted into a specially designed printer, along with another cartridge containing a gel known as bio-paper." In bioprinting, there are three major types of printers that have been used. These are inkjet, laser-assisted, and extrusion printers. Inkjet printers are mainly used in bioprinting for fast and large-scale products. One type of inkjet printer, called drop-on-demand inkjet printer, prints materials in exact amounts, minimizing cost and waste. Printers that utilize lasers provide high-resolution printing; however, these printers are often expensive. Extrusion printers print cells layer-by-layer, just like 3D printing to create 3D constructs. In addition to just cells, extrusion printers may also use hydrogels infused with cells. | 2 | Tissue Engineering |
Methanediol, rather than formaldehyde, is listed as one of the main ingredients of "Brazilian blowout", a hair-straightening formula marketed in the United States. The equilibrium with formaldehyde has caused concern since formaldehyde in hair straighteners is a health hazard. Research funded by the Professional Keratin Smoothing Council (PKSC), an industry association that represents selected manufacturers of professional-use only keratin smoothing products, has disputed the risk. | 6 | Carbohydrates |
Perhaps surprisingly, the effect of temperature is often greater than the effect of UV exposure. This can be seen in terms of the Arrhenius equation, which shows that reaction rates have an exponential dependence on temperature. By comparison the dependence of degradation rate on UV exposure and the availability of oxygen is broadly linear. As the oceans are cooler than land plastic pollution in the marine environment degrades more slowly. Materials buried in landfill do not degrade by photo-oxidation at all, though they may gradually decay by other processes.
Mechanical stress can effect the rate of photo-oxidation and may also accelerate the physical breakup of plastic objects. Stress can be caused by mechanical load (tensile and shear stresses) or even by temperature cycling, particularly in composite systems consisting of materials with differing temperature coefficients of expansion. Similarly, sudden rainfall can cause thermal stress. | 8 | Ultraviolet Radiation |
The most important operating parameters of disc filters are the height of the slurry tank, agitation and the intensity and rotation speed of the disc as these will determine the cake formation and drying times. It is important to continuously agitate the slurry in order to prevent sedimentation of the solids. Excessively high agitation intensity may affect cake formation or change the particle size distribution of the product. One of the most commonly used agitators for filtration using vacuum disc filters is an oscillating cradle-type agitator located in the bottom of the basin, which requires fairly high rotation speeds to form homogeneous slurry. For processing rapidly settling high concentration slurries, bottom-feed rotary disc filters are usually used.
Stage 1: Filtration
The filtrate from the internal passages of the discs is removed by the low vacuum used in the filter, while the small pressure differential across the disc causes cake formation. With a thicker cake produced in this stage, more effective washing is achieved at higher wash liquor flows. However, this causes larger air volumes to be consumed at discharge due to reduced resistance and marginally lower cake moisture.
Stage 2: Dewatering
In rare cases, due to the even structure of the cakes formed, the steady flow profile of the ceramic filter media and the gas free filtrate flow cake, washing has proved to be efficient in ceramic disc filters. The formation of thicker cakes during filtration and higher vacuum level leads to greater removal of solute.
Stage 3: Discharge
The basic scraper works well when the cakes are relatively thick and non-sticky. The final cakes are discharged by blade or wire scrapers on either side of the discs However, other types of agitators should be considered and installed if the cake is sticky or thin. An air blow-back system is often employed to aid cake removal where wetter cakes are discharged from disc filter. | 5 | Separation Processes |
The MCSGP process consists of several, at least two, chromatographic columns which are switched in position opposite to the flow direction. Most of the columns are equipped with a gradient pump to adjust the modifier concentration at the column inlet. Some columns are connected directly, so that non pure product streams are internally recycled. Other columns are short circuited, so that they operate in pure batch mode. The system is split into several sections, from which every section performs a tasks analogous to the tasks of a batch purification. These tasks are loading the feed, running the gradient elution, recycling of weakly adsorbing site fractions, fractionation of the purified product, recycling of strongly adsorbing site fractions, cleaning the column from strongly adsorbing impurities, cleaning in place and re-equilibration of the column to start the next purification run. All of the tasks mentioned here are carried out at the same time in one unit. Recycling of non-pure side fractions is performed in countercurrent movement. | 5 | Separation Processes |
Phosphorescent materials release the absorbed energy only slowly, so that they exhibit an "afterglow". Materials for stamp tagging absorb ultraviolet light of wavelengths between 180 nm and 300 nm (UVC, short-wave UV) and emit light of a greenish or reddish colour depending on the substances used. | 0 | Luminescence |
Bene Meat Technologies a.s. (BMT) is a Czech biotechnology start-up focused on research and development of technology for the production of cultivated meat on an industrial scale. It cooperates with scientific institutions and companies in the Czech Republic and abroad. The company has its laboratories on the first floor of the Cube building in Vokovice, Prague. | 2 | Tissue Engineering |
Separation processes are of great economic importance as they are accounting for 40 – 90% of capital and operating costs in industry. The separation processes of mixtures are including besides others washing, extraction, pressing, drying, clarification, evaporation, crystallization and filtration. Often several separation processes are performed successively. Separation operations are having several different functions:
* Purification of raw materials and products and recovery of by-products
* Recycling of solvents and unconverted reactants
* Removal of contaminants from effluents | 5 | Separation Processes |
Artificial spin ices are metamaterials consisting of coupled nanomagnets arranged on periodic and aperiodic lattices.
These systems have enabled the experimental investigation of a variety of phenomena such as frustration, emergent magnetic monopoles, and phase transitions. In addition, artificial spin ices show potential as reprogrammable magnonic crystals and have been studied for their fast dynamics. A variety of geometries have been explored, including quasicrystalline systems and 3D structures, as well as different magnetic materials to modify anisotropies and blocking temperatures.
For example, polymer magnetic composites comprising 2D lattices of droplets of solid-liquid phase change material, with each droplet containing a single magnetic dipole particle, form an artificial spin ice above the droplet melting point, and, after cooling, a spin glass state with low bulk remanence. Spontaneous emergence of 2D magnetic vortices was observed in such spin ices, which vortex geometries were correlated with the external bulk remanence.
Future work in this field includes further developments in fabrication and characterization methods, exploration of new geometries and material combinations, and potential applications in computation, data storage, and reconfigurable microwave circuits.
In 2021 a study demonstrated neuromorphic reservoir computing using artificial spin ice, solving a range of computational tasks using the complex magnetic dynamics of the artificial spin ice.
In 2022, another studied achieved an artificial kagome spin ice which could potentially be used in the future for novel high-speed computers with low power consumption. | 7 | Magnetic Ordering |
Carbohydrate metabolism is the series of biochemical processes responsible for the formation, breakdown and interconversion of carbohydrates in living organisms.
The most important carbohydrate is glucose, a simple sugar (monosaccharide) that is metabolized by nearly all known organisms. Glucose and other carbohydrates are part of a wide variety of metabolic pathways across species: plants synthesize carbohydrates from carbon dioxide and water by photosynthesis storing the absorbed energy internally, often in the form of starch or lipids. Plant components are consumed by animals and fungi, and used as fuel for cellular respiration. Oxidation of one gram of carbohydrate yields approximately 16 kJ (4 kcal) of energy, while the oxidation of one gram of lipids yields about 38 kJ (9 kcal). The human body stores between 300 and 500 g of carbohydrates depending on body weight, with the skeletal muscle contributing to a large portion of the storage. Energy obtained from metabolism (e.g., oxidation of glucose) is usually stored temporarily within cells in the form of ATP. Organisms capable of anaerobic and aerobic respiration metabolize glucose and oxygen (aerobic) to release energy, with carbon dioxide and water as byproducts. | 6 | Carbohydrates |
The UK at times has had one of the highest rates of acid attacks per capita in the world, though recent studies suggest that this is due to gang-related violence and possession offences, rather than traditional attacks found in lower middle-income countries, according to Acid Survivors Trust International (ASTI). NHS hospital figures record 144 assaults in 2011–2012 involving corrosive substances, which can include petrol, bleach and kerosene. Six years earlier, 56 such episodes were noted. The official records for 2017–2018 shows 150 patients in the UK admitted to hospital for "Assault by corrosive substance". In 2016, the Metropolitan Police in London recorded 454 attacks involving corrosive fluids in the city, with 261 in the previous year, indicating a rise of 36%. A rise of 30% was also recorded in the UK as a whole. Between 2005–2006 and 2011–2012 the number of assaults involving acid throwing and other corrosive substances tripled in England, official records show. According to Londons Metropolitan Police, 2017 was the worst year for acid attacks in London, with 465 attacks recorded, up from 395 the previous year and 255 in 2015. Acid attacks in London continued to rise in 2017. In July 2017, the BBCs George Mann reported that police statistics showed that: "Assaults involving corrosive substances have more than doubled in England since 2012. The vast majority of cases were in London." According to Time magazine, motives included organized crime, revenge, and domestic violence. According to Newham police, there is no trend of using acid in hate crimes.
According to data London's Metropolitan Police, a demographic breakdown of known suspects in London attacks for the period (2002–2016) showed White Europeans comprising 32% of suspects, Black Caribbeans 38% and Asian 6%. Victims for the same period were 45% White Europeans, 25% Black Caribbeans and 19% Asian. Of the total population, whites constitute 60%, blacks 13%, and Asians 18% as per the 2011 census of London. Known suspects were overwhelmingly male, 77% of known suspects were male and just 2% of suspects female. Four out of five victims in 2016 were male. In January 2018, CNN reported that acid attacks in London increased six-fold between 2012 and 2017 and that 71% of attackers and 72% of victims were male.
On 3 October 2017, the UK government announced that sales of acids to under 18s would be banned.
Mark van Dongen chose to undergo euthanasia months after he was attacked by his ex-girlfriend Berlinah Wallace during the early hours of 23 September 2015. He was left paralysed, scarred, had his lower left leg amputated and lost the sight in his left eye, as well as most of the sight in his right eye, following the incident. Wallace was found guilty of "throwing a corrosive substance with intent" and received a life sentence with a minimum term of 12 years.
In April 2017, a man named Arthur Collins, the ex-boyfriend of Ferne McCann, threw acid inside a nightclub across terrified clubbers in east London forcing a mass evacuation of 600 partygoers flooding into the street. 22 people were injured in the attack. Collins was sentenced to 20 years for the attack. Another similar attack is the 2017 Beckton acid attack. Katie Piper was also attacked in 2008 with acid by her ex-boyfriend Daniel Lynch and an accomplice Stefan Sylvestre.
In April 2019, a teenage girl, 13, and a woman, 63, were attacked by a man driving a white car, who poured sulphuric acid on them in Thornton Heath, South London.
The UK has subsequently banned possession of concentrated sulphuric acid without a licence and incidents of acid attacks have dropped substantially.
On 31 January 2024, nine people, including three police officers, were hospitalised after Abdul Shakoor Ezedi threw an alkaline solution on a car in Clapham, south west London. | 4 | Acids + Bases |
The main subprocesses of sensor-based sorting are material conditioning, material presentation, detection, data processing and separation.
* Material conditioning includes all operations which prepare the particles for being detected by the sensor. All optical sensors need clean material to be able to detect optical characteristics. Conditioning includes screening and cleaning of the feed material.
* The aim of the material presentation is the isolation of the particles by creating a single particle layer with the densest surface cover possible without particles touching each other and enough distance to each other allowing for a selective detection and rejection of each single particle.
There are two types of sensor-based sorters: the chute type and the belt type. For both types the first step in acceleration is spreading out the particles by a vibrating feeder followed by either a fast belt or a chute. On the belt type the sensor usually detects the particles horizontally while they pass it on the belt. For the chute type the material detection is usually done vertically while the material passes the sensor in a free fall. The data processing is done in real time by a computer. The computer transfers the result of the data processing to an ultra fast ejection unit which, depending on the sorting decision, ejects a particle or lets it pass. | 5 | Separation Processes |
By sperm washing, the risk that a chronic disease in the individual providing the sperm would infect the birthing parent or offspring can be brought to negligible levels.
If the sperm donor has hepatitis B, The Practice Committee of the American Society for Reproductive Medicine advises that sperm washing is not necessary in IVF to prevent transmission, unless the birthing partner has not been effectively vaccinated. In birthing people with hepatitis B, the risk of vertical transmission during IVF is no different from the risk in spontaneous conception. However, there is not enough evidence to say that ICSI procedures are safe in birthing people with hepatitis B in regard to vertical transmission to the offspring.
Regarding potential spread of HIV/AIDS, Japan's government prohibited the use of IVF procedures in which both partners are infected with HIV. Despite the fact that the ethics committees previously allowed the Ogikubo, Tokyo Hospital, located in Tokyo, to use IVF for couples with HIV, the Ministry of Health, Labour and Welfare of Japan decided to block the practice. Hideji Hanabusa, the vice president of the Ogikubo Hospital, states that together with his colleagues, he managed to develop a method through which scientists are able to remove HIV from sperm.
In the United States, people seeking to be an embryo recipient undergo infectious disease screening required by the Food and Drug Administration (FDA), and reproductive tests to determine the best placement location and cycle timing before the actual embryo transfer occurs. The amount of screening the embryo has already undergone is largely dependent on the genetic parents' own IVF clinic and process. The embryo recipient may elect to have their own embryologist conduct further testing. | 1 | Cryobiology |
Collagen, a major protein component of the ECM, provides support to tissues like skin, cartilage, bones, blood vessels and ligaments and is thus considered a model scaffold or matrix for tissue engineering due to its properties of biocompatibility, biodegradability and ability to promote cell binding. This ability allows chitosan to control distribution of cells inside the polymeric system. Thus, Type-I collagen obtained from animal tissues is now successfully being used commercially as tissue engineered biomaterial for multiple applications. Collagen has also been used in nerve repair and bladder engineering. Immunogenicity has limited the applications of collagen. Gelatin has been considered as an alternative for that reason. | 2 | Tissue Engineering |
Sensor-based sorting is a coarse particle separation technology applied in mining for the dry separation of bulk materials. The functional principle does not limit the technology to any kind of segment or mineral application but makes the technical viability mainly depend on the liberation characteristics at the size range , which is usually sorted. If physical liberation is present there is a good potential that one of the sensors available on industrial scale sorting machines can differentiate between valuable and non-valuable particles.
The separation is based on features measured with a detection technology that are used to derive a yes/no decision for actuation of usually pneumatic impulses. Sensor-based sorting is a disruptive technology in the mining industry which is universally applicable for all commodities. A comprehensive study examines both the technologys potential and its limitations, whilst providing a framework for application development and evaluation. All relevant aspects, from sampling to plant design and integration into mining and mineral processing systems, are covered. Other terminologies used in the industry include ore sorting, automated sorting, electronic sorting, and optical sorting'. | 5 | Separation Processes |
Lactulose is a non-absorbable sugar used in the treatment of constipation and hepatic encephalopathy. It is administered orally for constipation, and either orally or rectally for hepatic encephalopathy. It generally begins working after 8–12 hours, but may take up to 2 days to improve constipation.
Common side effects include abdominal bloating and cramps. A potential exists for electrolyte problems as a result of the diarrhea it produces. No evidence of harm to the fetus has been found when used during pregnancy. It is generally regarded as safe during breastfeeding. It is classified as an osmotic laxative.
Lactulose was first made in 1929, and has been used medically since the 1950s. Lactulose is made from the milk sugar lactose, which is composed of two simple sugars, galactose and glucose. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. In 2021, it was the 265th most commonly prescribed medication in the United States, with more than 1million prescriptions. | 6 | Carbohydrates |
Following the approach of , the spectrum of the Hamiltonian for the XXX model
can be determined by the Bethe ansatz. In this context, for an appropriately defined family of operators dependent on a spectral parameter acting on the total Hilbert space with each , a Bethe vector is a vector of the form
where .
If the satisfy the Bethe equation
then the Bethe vector is an eigenvector of with eigenvalue .
The family as well as three other families come from a transfer matrix (in turn defined using a Lax matrix), which acts on along with an auxiliary space , and can be written as a block matrix with entries in ,
which satisfies fundamental commutation relations (FCRs) similar in form to the Yang–Baxter equation used to derive the Bethe equations. The FCRs also show there is a large commuting subalgebra given by the generating function , as , so when is written as a polynomial in , the coefficients all commute, spanning a commutative subalgebra which is an element of. The Bethe vectors are in fact simultaneous eigenvectors for the whole subalgebra. | 7 | Magnetic Ordering |
In magnetics, the maximum energy product is an important figure-of-merit for the strength of a permanent magnet material. It is often denoted and is typically given in units of either (kilojoules per cubic meter, in SI electromagnetism) or (mega-gauss-oersted, in gaussian electromagnetism). 1 MGOe is equivalent to .
During the 20th century, the maximum energy product of commercially available magnetic materials rose from around 1 MGOe (e.g. in KS Steel) to over 50 MGOe (in neodymium magnets). Other important permanent magnet properties include the remanence () and coercivity (); these quantities are also determined from the saturation loop and are related to the maximum energy product, though not directly. | 7 | Magnetic Ordering |