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Sensor-based sorting has been introduced by Wotruba and Harbeck as an umbrella term for all applications where particles are singularly detected by a sensor technique and then rejected by an amplified mechanical, hydraulic or pneumatic process. | 1 | Separation Processes |
The Food and Drug Administration (FDA) classifies tanning beds as "moderate risk" devices (changed in 2014 from "low risk"). It requires that devices carry a black box warning that they should not be used by individuals under the age of 18, but it has not banned their use by minors. , California, Delaware, the District of Columbia, Hawaii, Illinois, Kansas, Louisiana, Massachusetts, Minnesota, Nevada, New Hampshire, North Carolina, Oregon, Texas, Vermont and Washington have banned the use of tanning beds for minors under the age of 18. Other states strictly regulate indoor tanning under the age of 18, with most banning indoor tanning for persons under the age of 14 unless medically required, and some requiring the consent of a guardian for those aged 14–17. In 2010 under the Affordable Care Act, a 10% "tanning tax" was introduced, which is added to the fees charged by tanning facilities; it was expected to raise $2.7 billion for health care over ten years.
Tanning beds are regulated in the United States by the federal governments Code of Federal Regulations (21 CFR 1040.20). This is designed to ensure that the devices adhere to a set of safety rules, with the primary focus on sunbed and lamp manufacturers regarding maximum exposure times and product equivalence. Additionally, must have a "Recommended Exposure Schedule" posted on both the front of the tanning bed and in the owners manual, and list the original lamp that was certified for that particular tanning bed. Salon owners are required to replace the lamps with either exactly the same lamp, or a lamp that is certified by the lamp manufacturer to be.
States control regulations for salons, regarding operator training, sanitization of sunbeds and eyewear, and additional warning signs. Many states also ban or regulate the use of tanning beds by minors under the age of 18.
American osteopathic physician Joseph Mercola was prosecuted in 2016 by the Federal Trade Commission (FTC) for selling tanning beds to "reverse your wrinkles" and "slash your risk of cancer". The settlement meant that consumers who had purchased the devices were eligible for refunds totalling $5.3 million. Mercola had falsely claimed that the FDA "endorsed indoor tanning devices as safe", and had failed to disclose that he had paid the Vitamin D Council for its endorsement of his devices. The FTC said that it was deceptive for the defendants to fail to disclose that tanning is not necessary to produce vitamin D. | 4 | Ultraviolet Radiation |
Hypothermia has played a major role in the success or failure of many military campaigns, from Hannibals loss of nearly half his men in the Second Punic War (218 B.C.) to the near destruction of Napoleons armies in Russia in 1812. Men wandered around confused by hypothermia, some lost consciousness and died, others shivered, later developed torpor, and tended to sleep. Others too weak to walk fell on their knees; some stayed that way for some time resisting death. The pulse of some was weak and hard to detect; others groaned; yet others had eyes open and wild with quiet delirium. Deaths from hypothermia in Russian regions continued through the first and second world wars, especially in the Battle of Stalingrad.
Civilian examples of deaths caused by hypothermia occurred during the sinkings of the RMS Titanic and RMS Lusitania, and more recently of the MS Estonia.
Antarctic explorers developed hypothermia; Ernest Shackleton and his team measured body temperatures "below 94.2°, which spells death at home", though this probably referred to oral temperatures rather than core temperature and corresponded to mild hypothermia. One of Scott's team, Atkinson, became confused through hypothermia.
Nazi human experimentation during World War II amounting to medical torture included hypothermia experiments, which killed many victims. There were 360 to 400 experiments and 280 to 300 subjects, indicating some had more than one experiment performed on them. Various methods of rewarming were attempted: "One assistant later testified that some victims were thrown into boiling water for rewarming". | 0 | Cryobiology |
Twenty to fifty percent of hypothermia deaths are associated with paradoxical undressing. This typically occurs during moderate and severe hypothermia, as the person becomes disoriented, confused, and combative. They may begin discarding their clothing, which, in turn, increases the rate of heat loss.
Rescuers who are trained in mountain survival techniques are taught to expect this; however, people who die from hypothermia in urban environments who are found in an undressed state are sometimes incorrectly assumed to have been subjected to sexual assault.
One explanation for the effect is a cold-induced malfunction of the hypothalamus, the part of the brain that regulates body temperature. Another explanation is that the muscles contracting peripheral blood vessels become exhausted (known as a loss of vasomotor tone) and relax, leading to a sudden surge of blood (and heat) to the extremities, causing the person to feel overheated. | 0 | Cryobiology |
Perfusion storage methods can mechanically injury the vascular endothelium of the kidney, which leads to arterial thrombosis or fibrin deposition after reimplantation. Hill noted that, in human kidneys, fibrin deposition in the glomerulus after reimplantation and postoperative function, correlated with the length of perfusion storage. He had taken biopsies at revascularisation from human kidneys preserved by perfusion or ice storage, and showed by electron microscopy that endothelial disruption only occurred in those kidneys that had been perfused. Biopsies taken one hour after revascularisation showed platelets and fibrin adherent to any areas of denuded vascular basement membrane. A different type of vascular damage was described by Sheil who showed how a jet lesion could be produced distal to the cannula tied into the renal artery, leading to arterial thrombosis approximately 1 cm distal to the cannula site. | 0 | Cryobiology |
Magnetomechanical effects connect magnetic, mechanical and electric phenomena in solid materials.
* Magnetostriction
* Inverse magnetostrictive effect
* Wiedemann effect
* Matteucci effect
* Guillemin effect
Magnetostriction is thermodynamically opposite to inverse magnetostriction effect. The same situation occurs for Wiedemann and Matteuci effects.
For magnetic, mechanical and electric phenomena in fluids see Magnetohydrodynamics and Electrohydrodynamics. | 3 | Magnetic Ordering |
Although the metabolism of fructose and glucose share many of the same intermediate structures, they have very different metabolic fates in human metabolism. Fructose is metabolized almost completely in the liver in humans, and is directed toward replenishment of liver glycogen and triglyceride synthesis, while much of dietary glucose passes through the liver and goes to skeletal muscle, where it is metabolized to CO, HO and ATP, and to fat cells where it is metabolized primarily to glycerol phosphate for triglyceride synthesis as well as energy production. The products of fructose metabolism are liver glycogen and de novo lipogenesis of fatty acids and eventual synthesis of endogenous triglyceride. This synthesis can be divided into two main phases: The first phase is the synthesis of the trioses, dihydroxyacetone (DHAP) and glyceraldehyde; the second phase is the subsequent metabolism of these trioses either in the gluconeogenic pathway for glycogen replenishment and/or the complete metabolism in the fructolytic pathway to pyruvate, which enters the Krebs cycle, is converted to citrate and subsequently directed toward de novo synthesis of the free fatty acid palmitate. | 2 | Carbohydrates |
The first writer to advocate a lectin-free diet was Peter J. DAdamo, a naturopathic physician best known for promoting the Blood type diet. He argued that lectins may damage a persons blood type by interfering with digestion, food metabolism, hormones, insulin production—and so should be avoided. D'Adamo provided no scientific evidence nor published data for his claims, and his diet has been criticized for making inaccurate statements about biochemistry.
Steven Gundry proposed a lectin-free diet in his book The Plant Paradox (2017). It excludes a large range of commonplace foods including whole grains, legumes, and most fruit, as well as the nightshade vegetables: tomatoes, potatoes, eggplant, bell peppers, and chili peppers. Gundry's claims about lectins are considered pseudoscience. His book cites studies that have nothing to do with lectins, and some that show—contrary to his own recommendations—that avoiding the whole grains wheat, barley, and rye will allow increase of harmful bacteria while diminishing helpful bacteria. | 2 | Carbohydrates |
Spinning band distillation is a technique used to separate liquid mixtures which are similar in boiling points. When liquids with similar boiling points are distilled, the vapors are mixtures, and not pure compounds. Fractionating columns help separate the mixture by allowing the mixed vapors to cool, condense, and vaporize again in accordance with Raoult's law. With each condensation-vaporization cycles, the vapors are enriched in a certain component. A larger surface area allows more cycles, improving separation.
Spinning band distillation takes this concept one step further by using a spinning helical band made of an inert material such as metal or Teflon to push the rising vapors and descending condensate to the sides of the column, coming into close contact with each other. This speeds up equilibration and provides for a greater number of condensation-vaporization cycles. | 1 | Separation Processes |
Abouna showed that ammonia was released into the perfusate during 3 day kidney storage, and suggested that this might be toxic to the kidney cells unless removed by frequent replacement of the perfusate. Some support for the use of perfusate exchange during long perfusions was provided by Liu who used perfusate exchange in his successful 7 day storage experiments. Grundmann also found that 96-hour preservation quality was improved by the use of a double volume of perfusate or by perfusate exchange. However, Grundmann's conclusions were based on comparisons with a control group of only 3 dogs. Cohen was unable to demonstrate any production of ammonia during 8 days of perfusion and no benefit from perfusate exchange; the progressive alkalinity that occurred during perfusion was shown to be due to bicarbonate production. | 0 | Cryobiology |
UV curing (ultraviolet curing) is the process by which ultraviolet light initiates a photochemical reaction that generates a crosslinked network of polymers through radical polymerization or cationic polymerization. UV curing is adaptable to printing, coating, decorating, stereolithography, and in the assembly of a variety of products and materials. UV curing is a low-temperature, high speed, and solventless process as curing occurs via polymerization. Originally introduced in the 1960s, this technology has streamlined and increased automation in many industries in the manufacturing sector. | 4 | Ultraviolet Radiation |
Selecting an oocyte for in vitro fertilization involves assessing the quality of the oocyte which is usually done by accessing the morphological features of the oocyte. The major parts of the oocyte that are accessed for quality in terms of morphological characteristics are the cumulus cells, zona pellucida, polar body, perivitelline space, and cytoplasm; These are the main parts of the oocyte and are usually assessed by conventional microscopy. The size of an oocyte is another factor of the quality of the oocyte; Larger oocyte are usually more quality than smaller ones. Chromosomal evaluation may be performed. Embryos from rescued in vitro-matured metaphase II (IVM-MII) oocytes show significantly higher fertilization rates and more blastomeres per embryo compared with those from arrested metaphase I (MI) oocytes (58.5% vs. 43.9% and 5.7 vs. 5.0, respectively).
Also, morphological features of the oocyte that can be obtained by standard light or polarized light microscopy. However, there is no clear tendency in recent publications to a general increase in predictive value of morphological features. Suggested techniques include zona pellucida imaging, which can detect differences in birefringence between eggs, which is a predictor of compaction, blastulation and pregnancy.
Potentially, polar body biopsy may be used for molecular analysis, and can be used for preimplantation genetic screening. | 0 | Cryobiology |
Spin ices are geometrically frustrated magnetic systems. While frustration is usually associated with triangular or tetrahedral arrangements of magnetic moments coupled via antiferromagnetic exchange interactions, as in Andersons Ising model, spin ices are frustrated ferromagnets. It is the very strong local magnetic anisotropy from the crystal field forcing the magnetic moments to point either in or out of a tetrahedron that renders ferromagnetic interactions frustrated in spin ices. Most importantly, it is the long-range magnetostatic dipole–dipole interaction, and not' the nearest-neighbor exchange, that causes the frustration and the consequential two-in, two-out rule that leads to the spin ice phenomenology.
For a tetrahedron in a two-in, two-out state, the magnetization field is divergent-free; there is as much "magnetization intensity" entering a tetrahedron as there is leaving (see figure 3). In such a divergent-free situation, there exists no source or sink for the field. According to Gauss theorem (also known as Ostrogradskys theorem), a nonzero divergence of a field is caused, and can be characterized, by a real number called "charge". In the context of spin ice, such charges characterizing the violation of the two-in, two-out magnetic moment orientation rule are the aforementioned monopoles.
In Autumn 2009, researchers reported experimental observation of low-energy quasiparticles resembling the predicted monopoles in spin ice. A single crystal of the dysprosium titanate spin ice candidate was examined in the temperature range of 0.6–2.0K. Using neutron scattering, the magnetic moments were shown to align in the spin ice material into interwoven tube-like bundles resembling Dirac strings. At the defect formed by the end of each tube, the magnetic field looks like that of a monopole. Using an applied magnetic field, the researchers were able to control the density and orientation of these strings. A description of the heat capacity of the material in terms of an effective gas of these quasiparticles was also presented.
The effective charge of a magnetic monopole, Q (see figure 3) in both the dysprosium and holmium titanate spin ice compounds is approximately (Bohr magnetons per angstrom). The elementary magnetic constituents of spin ice are magnetic dipoles, so the emergence of monopoles is an example of the phenomenon of fractionalization.
The microscopic origin of the atomic magnetic moments in magnetic materials is quantum mechanical; the Planck constant enters explicitly in the equation defining the magnetic moment of an electron, along with its charge and its mass. Yet, the magnetic moments in the dysprosium titanate and the holmium titanate spin ice materials are effectively described by classical statistical mechanics, and not quantum statistical mechanics, over the experimentally relevant and reasonably accessible temperature range (between 0.05K and 2K) where the spin ice phenomena manifest themselves. Although the weakness of quantum effects in these two compounds is rather unusual, it is believed to be understood. There is current interest in the search of quantum spin ices, materials in which the laws of quantum mechanics now become needed to describe the behavior of the magnetic moments. Magnetic ions other than dysprosium (Dy) and holmium (Ho) are required to generate a quantum spin ice, with praseodymium (Pr), terbium (Tb) and ytterbium (Yb) being possible candidates. One reason for the interest in quantum spin ice is the belief that these systems may harbor a quantum spin liquid, a state of matter where magnetic moments continue to wiggle (fluctuate) down to absolute zero temperature. The theory describing the low-temperature and low-energy properties of quantum spin ice is akin to that of vacuum quantum electrodynamics, or QED. This constitutes an example of the idea of emergence. | 3 | Magnetic Ordering |
A 2009 statement from the ASRM found no persuasive evidence that children are harmed or disadvantaged solely by being raised by single parents, unmarried parents, or homosexual parents. It did not support restricting access to assisted reproductive technologies on the basis of a prospective parents marital status or sexual orientation. A 2018 study found that childrens psychological well-being did not differ when raised by either same-sex parents or heterosexual parents, even finding that psychological well-being was better amongst children raised by same-sex parents.
Ethical concerns include reproductive rights, the welfare of offspring, nondiscrimination against unmarried individuals, homosexual, and professional autonomy.
A controversy in California focused on the question of whether physicians opposed to same-sex relationships should be required to perform IVF for a lesbian couple. Guadalupe T. Benitez, a lesbian medical assistant from San Diego, sued doctors Christine Brody and Douglas Fenton of the North Coast Womans Care Medical Group after Brody told her that she had "religious-based objections to treating her and homosexuals in general to help them conceive children by artificial insemination," and Fenton refused to authorise a refill of her prescription for the fertility drug Clomid on the same grounds. The California Medical Association had initially sided with Brody and Fenton, but the case, North Coast Womens Care Medical Group v. Superior Court, was decided unanimously by the California State Supreme Court in favour of Benitez on 19 August 2008.
Nadya Suleman came to international attention after having twelve embryos implanted, eight of which survived, resulting in eight newborns being added to her existing six-child family. The Medical Board of California sought to have fertility doctor Michael Kamrava, who treated Suleman, stripped of his licence. State officials allege that performing Sulemans procedure is evidence of unreasonable judgment, substandard care, and a lack of concern for the eight children she would conceive and the six she was already struggling to raise. On 1 June 2011 the Medical Board issued a ruling that Kamravas medical licence be revoked effective 1 July 2011. | 0 | Cryobiology |
After the sample has been processed for cryoprotection, the sperm is stored in small vials or straws holding between 0.4 and 1.0 ml of sperm and then cryogenically preserved in liquid nitrogen tanks. Two approaches for sperm cryoperservation include conventional freezing and vitrification. The conventional technique consists of a slow freezing process that is most commonly used for assisted reproduction technologies (ART). Whereas the vitrification method is a faster approach for sperm cryopreservation in converting liquid to solid state. The disadvantage of this latter process is increase in contamination from the liquid nitrogen and smaller sperm sample size to improve the speed for high cooling rate.
It has been proposed that there should be an upper limit on how long frozen sperm can be stored; however, a baby has been conceived in the United Kingdom using sperm frozen for 21 years and andrology experts believe sperm can be frozen indefinitely. The UK government places an upper limit for storage of 55 years.
Following the necessary quarantine period, which is usually six months, a sample will be thawed. To thaw a sperm sample, the vial or straw is left at room temperature for approximately 30 minutes, and then brought to body temperature by holding it in the hands of the person performing the insemination. Once a sperm sample is thawed, it cannot be frozen again, and should be used to artificially inseminate a recipient or used for another assisted reproduction technologies (ART) treatment immediately.
Freeze-drying is another promising alternative for storing semen for its accessibility with regular refrigerator. This method has been successfully replicated in animal species. However, DNA can be damaged in this process, therefore further research is warranted to determine factors that can effect the efficacy of this method. | 0 | Cryobiology |
Direct experimental evidence of altermagnetic band structure in semiconducting MnTe and metallic RuO was first published in 2024. Many more materials are predicted to be altermagnets – ranging from insulators, semiconductors, and metals to superconductors. Altermagnetism was predicted in 3d and 2d materials with both light as well as heavy elements and can be found in nonrelativistic as well as relativistic band structures. | 3 | Magnetic Ordering |
Using multi-spectral imaging it is possible to read illegible papyrus, such as the burned papyri of the Villa of the Papyri or of Oxyrhynchus, or the Archimedes palimpsest. The technique involves taking pictures of the illegible document using different filters in the infrared or ultraviolet range, finely tuned to capture certain wavelengths of light. Thus, the optimum spectral portion can be found for distinguishing ink from paper on the papyrus surface.
Simple NUV sources can be used to highlight faded iron-based ink on vellum. | 4 | Ultraviolet Radiation |
Commercial tanning services are banned in all states, except the Northern Territory where no salons are in operation. Private ownership of tanning beds is permitted. | 4 | Ultraviolet Radiation |
Independently of the range of the interaction, at low enough temperature the magnetization is positive.
Conjecturally, in each of the low temperature extremal states the truncated correlations decay algebraically. | 3 | Magnetic Ordering |
In 1737 Andrew Rodger, a farmer on the estate of Cavers in Roxburghshire, developed a winnowing machine for corn, called a Fanner. These were successful and the family sold them throughout Scotland for many years. Some Scottish Presbyterian ministers saw the fanners as sins against God, for the wind was a thing specially made by him and an artificial wind was a daring and impious attempt to usurp what belonged to God alone. As the Industrial Revolution progressed, the winnowing process was mechanized by the invention of additional winnowing machines, such as fanning mills. | 1 | Separation Processes |
Ultraviolet (UV) light is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs, Cherenkov radiation, and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights.
The photons of ultraviolet have greater energy than those of visible light, from about 3.1 to 12 electron volts, around the minimum energy required to ionize atoms. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack sufficient energy, it can induce chemical reactions and cause many substances to glow or fluoresce. Many practical applications, including chemical and biological effects, are derived from the way that UV radiation can interact with organic molecules. These interactions can involve absorption or adjusting energy states in molecules, but do not necessarily involve heating. Short-wave ultraviolet light is ionizing radiation. Consequently, short-wave UV damages DNA and sterilizes surfaces with which it comes into contact.
For humans, suntan and sunburn are familiar effects of exposure of the skin to UV light, along with an increased risk of skin cancer. The amount of UV light produced by the Sun means that the Earth would not be able to sustain life on dry land if most of that light were not filtered out by the atmosphere. More energetic, shorter-wavelength "extreme" UV below 121 nm ionizes air so strongly that it is absorbed before it reaches the ground. However, ultraviolet light (specifically, UVB) is also responsible for the formation of vitamin D in most land vertebrates, including humans. The UV spectrum, thus, has effects both beneficial and detrimental to life.
The lower wavelength limit of the visible spectrum is conventionally taken as 400 nm, so ultraviolet rays are not visible to humans, although people can sometimes perceive light at shorter wavelengths than this. Insects, birds, and some mammals can see near-UV (NUV), i.e., slightly shorter wavelengths than what humans can see. | 4 | Ultraviolet Radiation |
Some animals, including birds, reptiles, and insects such as bees, can see near-ultraviolet wavelengths. Many fruits, flowers, and seeds stand out more strongly from the background in ultraviolet wavelengths as compared to human color vision. Scorpions glow or take on a yellow to green color under UV illumination, thus assisting in the control of these arachnids. Many birds have patterns in their plumage that are invisible at usual wavelengths but observable in ultraviolet, and the urine and other secretions of some animals, including dogs, cats, and human beings, are much easier to spot with ultraviolet. Urine trails of rodents can be detected by pest control technicians for proper treatment of infested dwellings.
Butterflies use ultraviolet as a communication system for sex recognition and mating behavior. For example, in the Colias eurytheme butterfly, males rely on visual cues to locate and identify females. Instead of using chemical stimuli to find mates, males are attracted to the ultraviolet-reflecting color of female hind wings. In Pieris napi butterflies it was shown that females in northern Finland with less UV-radiation present in the environment possessed stronger UV signals to attract their males than those occurring further south. This suggested that it was evolutionarily more difficult to increase the UV-sensitivity of the eyes of the males than to increase the UV-signals emitted by the females.
Many insects use the ultraviolet wavelength emissions from celestial objects as references for flight navigation. A local ultraviolet emitter will normally disrupt the navigation process and will eventually attract the flying insect.
The green fluorescent protein (GFP) is often used in genetics as a marker. Many substances, such as proteins, have significant light absorption bands in the ultraviolet that are of interest in biochemistry and related fields. UV-capable spectrophotometers are common in such laboratories.
Ultraviolet traps called bug zappers are used to eliminate various small flying insects. They are attracted to the UV and are killed using an electric shock, or trapped once they come into contact with the device. Different designs of ultraviolet radiation traps are also used by entomologists for collecting nocturnal insects during faunistic survey studies. | 4 | Ultraviolet Radiation |
The fact that the binding motif appears as a "triplet" of the conserved TxT repeat, as well as the observation that blastp queries have returned no viable matches, has led some researchers to suggest that RiAFP represents a new type of AFP – one that differs from the heavily studied TmAFP (from T. molitor), DcAFP (from D. canadensis), and CfAFP (from C. fumiferana). On the basis of these observations, it has been predicted that the need for insect AFPs came about after insect evolutionary divergence, much like the evolution of fish AFPs; thus, different AFPs most likely evolved in parallel from adaptations to cold (environmental) stress. As a result, homology modelling with TmAFP, DcAFP, or CfAFP would prove to be fruitless.
Secondary structure modelling algorithms have determined that the internal repeats are spaced sufficiently to tend towards β-strand configuration; no helical regions include the conserved repeats; and all turn regions are located at the ends of β-strand regions. These data suggest that RiAFP is a well-folded β-helical protein, having six β-strand regions consisting of 13-amino acids (including one TxTxTxT binding motif) per strand.
Primary crystallographic studies, have been published on a RiAFP crystal (which diffracted to 1.3Å resolution) in the trigonal space group P321 (or P321), with unit-cell parameters a = b = 46.46, c = 193.21Å. | 0 | Cryobiology |
The research on transgender reproduction and family planning is limited. A 2020 comparative study of children born to a transgender father and cisgender mother via donor sperm insemination in France showed no significant differences to IVF and naturally conceived children of cisgender parents.
Transgender men can experience challenges in pregnancy and birthing from the cis-normative structure within the medical system, as well as psychological challenges such as renewed gender dysphoria. The effect of continued testosterone therapy during pregnancy and breastfeeding is undetermined. Ethical concerns include reproductive rights, reproductive justice, physician autonomy, and transphobia within the health care setting. | 0 | Cryobiology |
It is not necessary that the embryo transfer be performed on the female who provided the eggs. Thus another female whose uterus is appropriately prepared can receive the embryo and become pregnant.
Embryo transfer may be used where a woman who has eggs but no uterus and wants to have a biological baby; she would require the help of a gestational carrier or surrogate to carry the pregnancy. Also, a woman who has no eggs but a uterus may utilize egg donor IVF, in which case another woman would provide eggs for fertilization and the resulting embryos are placed into the uterus of the patient. Fertilization may be performed using the womans partners sperm or by using donor sperm. Spare embryos which are created for another couple undergoing IVF treatment but which are then surplus to that couples needs may also be transferred (called embryo donation). Embryos may be specifically created by using eggs and sperm from donors and these can then be transferred into the uterus of another woman. A surrogate may carry a baby produced by embryo transfer for another couple, even though neither she nor the commissioning' couple is biologically related to the child. Third party reproduction is controversial and regulated in many countries. Persons entering gestational surrogacy arrangements must make sense of an entirely new type of relationship that does not fit any of the traditional scripts we use to categorize relations as kinship, friendship, romantic partnership or market relations. Surrogates have the experience of carrying a baby that they conceptualize as not of their own kin, while intended mothers have the experience of waiting through nine months of pregnancy and transitioning to motherhood from outside of the pregnant body. This can lead to new conceptualizations of body and self. | 0 | Cryobiology |
Alpha-glucosidases are targeted by alpha-glucosidase inhibitors such as acarbose and miglitol to control diabetes mellitus type 2. | 2 | Carbohydrates |
Addiction to indoor tanning has been recognized as a psychiatric disorder. The disorder is characterized as excessive indoor tanning that causes the subject personal distress; it has been associated with anxiety, eating disorders and smoking. The media has described the addiction as tanorexia. According to the Canadian Pediatric Society, "repeated UVR exposures, and the use of indoor tanning beds specifically, may have important systemic and behavioural consequences, including mood changes, compulsive disorders, pain and physical dependency." | 4 | Ultraviolet Radiation |
Lectins may bind to a soluble carbohydrate or to a carbohydrate moiety that is a part of a glycoprotein or glycolipid. They typically agglutinate certain animal cells and/or precipitate glycoconjugates. Most lectins do not possess enzymatic activity. | 2 | Carbohydrates |
Sensor-based ore sorting is the terminology used in the mining industry. It is a coarse physical coarse particle separation technology usually applied in the size range for . Aim is either to create a lumpy product in ferrous metals, coal or industrial minerals applications or to reject waste before it enters production bottlenecks and more expensive comminution and concentration steps in the process.
In the majority of all mining processes, particles of sub-economic grade enter the traditional comminution, classification and concentration steps. If the amount of sub-economic material in the above-mentioned fraction is roughly 25% or more, there is good potential that sensor-based ore sorting is a technically and financially viable option. High added value can be achieved with relatively low capital expenditure, especially when increasing the productivity through downstream processing of higher grade feed and through increased overall recovery when rejecting deleterious waste. | 1 | Separation Processes |
In those without signs of life, cardiopulmonary resuscitation (CPR) should be continued during active rewarming. For ventricular fibrillation or ventricular tachycardia, a single defibrillation should be attempted. However, people with severe hypothermia may not respond to pacing or defibrillation. It is not known if further defibrillation should be withheld until the core temperature reaches . In Europe, epinephrine is not recommended until the person's core temperature reaches , while the American Heart Association recommends up to three doses of epinephrine before a core temperature of is reached. Once a temperature of has been reached, normal ACLS protocols should be followed. | 0 | Cryobiology |
The following steps convert in a conventional n-type DSSC photons (light) to current:
The efficiency of a DSSC depends on four energy levels of the component: the excited state (approximately LUMO) and the ground state (HOMO) of the photosensitizer, the Fermi level of the TiO electrode and the redox potential of the mediator (I/I) in the electrolyte. | 4 | Ultraviolet Radiation |
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%. | 0 | Cryobiology |
UVGI can be used to disinfect air with prolonged exposure. In the 1930s and 40s, an experiment in public schools in Philadelphia showed that upper-room ultraviolet fixtures could significantly reduce the transmission of measles among students. In 2020, UVGI is again being researched as a possible countermeasure against COVID-19.
UV and violet light are able to neutralize the infectivity of SARS-CoV-2. Viral titers usually found in the sputum of COVID-19 patients are completely inactivated by levels of UV-A and UV-B irradiation that are similar to those levels experienced from natural sun exposure. This finding suggests that the reduced incidence of SARS-COV-2 in the summer may be, in part, due to the neutralizing activity of solar UV irradiation.
Various UV-emitting devices can be used for SARS-CoV-2 disinfection, and these devices may help in reducing the spread of infection. SARS-CoV-2 can be inactivated by a wide range of UVC wavelengths, and the wavelength of 222 nm provides the most effective disinfection performance.
Disinfection is a function of UV intensity and time. For this reason, it is in theory not as effective on moving air, or when the lamp is perpendicular to the flow, as exposure times are dramatically reduced. However, numerous professional and scientific publications have indicated that the overall effectiveness of UVGI actually increases when used in conjunction with fans and HVAC ventilation, which facilitate whole-room circulation that exposes more air to the UV source. Air purification UVGI systems can be free-standing units with shielded UV lamps that use a fan to force air past the UV light. Other systems are installed in forced air systems so that the circulation for the premises moves microorganisms past the lamps. Key to this form of sterilization is placement of the UV lamps and a good filtration system to remove the dead microorganisms. For example, forced air systems by design impede line-of-sight, thus creating areas of the environment that will be shaded from the UV light. However, a UV lamp placed at the coils and drain pans of cooling systems will keep microorganisms from forming in these naturally damp places. | 4 | Ultraviolet Radiation |
Fluorescent black light tubes are typically made in the same fashion as normal fluorescent tubes except that a phosphor that emits UVA light instead of visible white light is used on the inside of the tube. The type most commonly used for black lights, designated blacklight blue or "BLB" by the industry, has a dark blue filter coating on the tube, which filters out most visible light, so that fluorescence effects can be observed. These tubes have a dim violet glow when operating. They should not be confused with "blacklight" or "BL" tubes, which have no filter coating, and have a brighter blue color. These are made for use in "bug zapper" insect traps where the emission of visible light does not interfere with the performance of the product. The phosphor typically used for a near 368 to 371 nanometer emission peak is either europium-doped strontium fluoroborate (:) or europium-doped strontium borate (:) while the phosphor used to produce a peak around 350 to 353 nanometres is lead-doped barium silicate (:). "Blacklight blue" lamps peak at 365 nm.
Manufacturers use different numbering systems for black light tubes. Philips uses one system which is becoming outdated (2010), while the (German) Osram system is becoming dominant outside North America. The following table lists the tubes generating blue, UVA and UVB, in order of decreasing wavelength of the most intense peak. Approximate phosphor compositions, major manufacturer's type numbers and some uses are given as an overview of the types available. "Peak" position is approximated to the nearest 10 nm. "Width" is the measure between points on the shoulders of the peak that represent 50% intensity. | 4 | Ultraviolet Radiation |
The oldest known magnetic material, magnetite, is a ferrimagnetic substance. The tetrahedral and octahedral sites of its crystal structure exhibit opposite spin. Other known ferrimagnetic materials include yttrium iron garnet (YIG); cubic ferrites composed of iron oxides with other elements such as aluminum, cobalt, nickel, manganese, and zinc; and hexagonal or spinel type ferrites, including rhenium ferrite, ReFeO, PbFeO and BaFeO and pyrrhotite, FeS.
Ferrimagnetism can also occur in single-molecule magnets. A classic example is a dodecanuclear manganese molecule with an effective spin S = 10 derived from antiferromagnetic interaction on Mn(IV) metal centers with Mn(III) and Mn(II) metal centers. | 3 | Magnetic Ordering |
Possible complications may include: infection, bleeding, dysrhythmias and high blood sugar. One review found an increased risk of pneumonia and sepsis but not the overall risk of infection. Another review found a trend towards increased bleeding but no increase in severe bleeding. Hypothermia induces a "cold diuresis" which can lead to electrolyte abnormalities – specifically hypokalemia, hypomagnesaemia, and hypophosphatemia, as well as hypovolemia. | 0 | Cryobiology |
The effectiveness of germicidal UV depends on the duration a microorganism is exposed to UV, the intensity and wavelength of the UV radiation, the presence of particles that can protect the microorganisms from UV, and a microorganism's ability to withstand UV during its exposure.
In many systems, redundancy in exposing microorganisms to UV is achieved by circulating the air or water repeatedly. This ensures multiple passes so that the UV is effective against the highest number of microorganisms and will irradiate resistant microorganisms more than once to break them down.
"Sterilization" is often misquoted as being achievable. While it is theoretically possible in a controlled environment, it is very difficult to prove and the term "disinfection" is generally used by companies offering this service as to avoid legal reprimand. Specialist companies will often advertise a certain log reduction, e.g., 6-log reduction or 99.9999% effective, instead of sterilization. This takes into consideration a phenomenon known as light and dark repair (photoreactivation and base excision repair, respectively), in which a cell can repair DNA that has been damaged by UV light.
The effectiveness of this form of disinfection depends on line-of-sight exposure of the microorganisms to the UV light. Environments where design creates obstacles that block the UV light are not as effective. In such an environment, the effectiveness is then reliant on the placement of the UVGI system so that line of sight is optimum for disinfection.
Dust and films coating the bulb lower UV output. Therefore, bulbs require periodic cleaning and replacement to ensure effectiveness. The lifetime of germicidal UV bulbs varies depending on design. Also, the material that the bulb is made of can absorb some of the germicidal rays.
Lamp cooling under airflow can also lower UV output. Increases in effectiveness and UV intensity can be achieved by using reflection. Aluminum has the highest reflectivity rate versus other metals and is recommended when using UV.
One method for gauging UV effectiveness in water disinfection applications is to compute UV dose. The U.S. Environmental Protection Agency (EPA) published UV dosage guidelines for water treatment applications in 1986. UV dose cannot be measured directly but can be inferred based on the known or estimated inputs to the process:
* Flow rate (contact time)
* Transmittance (light reaching the target)
* Turbidity (cloudiness)
* Lamp age or fouling or outages (reduction in UV intensity)
In air and surface disinfection applications the UV effectiveness is estimated by calculating the UV dose which will be delivered to the microbial population. The UV dose is calculated as follows:
: UV dose (μW·s/cm) = UV intensity (μW/cm) × exposure time (seconds)
The UV intensity is specified for each lamp at a distance of 1 meter. UV intensity is inversely proportional to the square of the distance so it decreases at longer distances. Alternatively, it rapidly increases at distances shorter than 1m. In the above formula, the UV intensity must always be adjusted for distance unless the UV dose is calculated at exactly from the lamp. Also, to ensure effectiveness, the UV dose must be calculated at the end of lamp life (EOL is specified in number of hours when the lamp is expected to reach 80% of its initial UV output) and at the furthest distance from the lamp on the periphery of the target area. Some shatter-proof lamps are coated with a fluorated ethylene polymer to contain glass shards and mercury in case of breakage; this coating reduces UV output by as much as 20%.
To accurately predict what UV dose will be delivered to the target, the UV intensity, adjusted for distance, coating, and end of lamp life, will be multiplied by the exposure time. In static applications the exposure time can be as long as needed for an effective UV dose to be reached. In case of rapidly moving air, in AC air ducts, for example, the exposure time is short, so the UV intensity must be increased by introducing multiple UV lamps or even banks of lamps. Also, the UV installation should ideally be located in a long straight duct section with the lamps directing UVC in a direction parallel to the airflow to maximize the time the air is irradiated.
These calculations actually predict the UV fluence and it is assumed that the UV fluence will be equal to the UV dose. The UV dose is the amount of germicidal UV energy absorbed by a microbial population over a period of time. If the microorganisms are planktonic (free floating) the UV fluence will be equal the UV dose. However, if the microorganisms are protected by mechanical particles, such as dust and dirt, or have formed biofilm a much higher UV fluence will be needed for an effective UV dose to be introduced to the microbial population. | 4 | Ultraviolet Radiation |
Subject to any regulations restricting who can obtain donor sperm, donor sperm is available to all people who, for whatever reason, wish to have a child. These regulations vary significantly across jurisdictions, and some countries do not have any regulations. When an individual finds that they are barred from receiving donor sperm within their jurisdiction, they may travel to another jurisdiction to obtain sperm. Regulations change from time to time. In most jurisdictions, donor sperm is available to an individual if their partner is infertile or where they have a genetic disorder. However, the categories of individuals who may obtain donor sperm is expanding, with its availability to single persons and to same-sex couples becoming more common, and some sperm banks supply fertility centers which specialize in the treatment of such people.
Frozen vials of donor sperm may be shipped by the sperm bank to a recipient's home for self-insemination, or they may be shipped to a fertility clinic or physician for use in fertility treatments. The sperm bank will rely on the recipient woman or medical practitioner to report the outcome of any use of the sperm to the sperm bank. This enables a sperm bank to adhere to any national limits of pregnancy numbers. The sperm bank may also impose its own worldwide limit on numbers.
Sperm is introduced into the recipient by means of artificial insemination or by IVF. The most common technique is conventional artificial insemination which consists of a catheter to put the sperm into the vagina where it is deposited at the entrance to the cervix. In biological terms, this is much the same process as when semen is ejaculated from the penis during sexual intercourse. Owing to its simplicity, this method of insemination is commonly used for home and self inseminations principally by single women and lesbians. Other types of uses include intrauterine insemination (IUI) and deep intrauterine artificial insemination where washed sperm must be used. These methods of insemination are most commonly used in fertility centers and clinics mainly because they produce better pregnancy rates than ICI insemination especially where the woman has no underlying fertility issues.
Men may also store their own sperm at a sperm bank for future use particularly where they anticipate traveling to a war zone or having to undergo chemotherapy which might damage the testes.
Sperm from a sperm donor may also be used in surrogacy arrangements and for creating embryos for embryo donation. Donor sperm may be supplied by the sperm bank directly to the recipient to enable a woman to perform her own artificial insemination which can be carried out using a needleless syringe or a cervical cap conception device. The cervical cap conception device allows the donor semen to be held in place close to the cervix for between six and eight hours to allow fertilization to take place. Alternatively, donor sperm can be supplied by a sperm bank through a registered medical practitioner who will perform an appropriate method of insemination or IVF treatment using the donor sperm in order for the woman to become pregnant. | 0 | Cryobiology |
The main components of a UV curing solution includes resins, monomers, and photoinitiators. Resin is an oligomer that imparts specific properties to the final polymer. A monomer is used as a cross-linking agent and regulates the viscosity of the mixture to suit the application. The photoinitiator is responsible for absorbing the light and kickstarting the reaction, which helps control the cure rate and depth of cure. Each of these elements has a role to play in the crosslinking process and is linked to the composition of the final polymer. | 4 | Ultraviolet Radiation |
The main sources of CSDB data are:
* Scientific publications indexed in the dedicated citation databases, including [https://www.ncbi.nlm.nih.gov/pubmed/ NCBI Pubmed] and [http://webofknowledge.com/ Thomson Reuters Web Of Science] (approx. 18000 records).
* CCSD (Carbbank ) database (approx. 3000 records).
The data are selected and added to CSDB manually by browsing original scientific publications. The data originating from other databases are subject to error-correction and approval procedures.
As of 2017, the coverage on bacteria and archaea is ca. 80% of carbohydrate structures published in scientific literature The time lag between the publication of relative data and their deposition into CSDB is about 18 months. Plants are covered up to 1997, and fungi up to 2012.
CSDB does not cover data from the animalia domain, except unicellular metazoa. There is a number of dedicated databases on animal carbohydrates, e.g. [http://www.unicarbkb.org/ UniCarbKB] or [http://glycosciences.de GLYCOSCIENCES.de] .
CSDB is reported as one of the biggest projects in glycoinformatics. It is employed in structural studies of natural carbohydrates and in glyco-profiling.
The content of CSDB has been used as a data source in other glycoinformatics projects. | 2 | Carbohydrates |
Reverse osmosis (RO) is a water purification process that uses a semi-permeable membrane to separate water molecules from other substances. RO applies pressure to overcome osmotic pressure that favors even distributions. RO can remove dissolved or suspended chemical species as well as biological substances (principally bacteria), and is used in industrial processes and the production of potable water. RO retains the solute on the pressurized side of the membrane and the purified solvent passes to the other side. It relies on the relative sizes of the various molecules to decide what passes through. "Selective" membranes reject large molecules, while accepting smaller molecules (such as solvent molecules, e.g., water).
RO is most commonly known for its use in drinking water purification from seawater, removing the salt and other effluent materials from the water molecules.
As of 2013 the world's largest RO desalination plant was in Sorek, Israel, outputting . | 1 | Separation Processes |
Trehalose is an ingredient, along with hyaluronic acid, in an artificial tears product used to treat dry eye. Outbreaks of Clostridium difficile were initially associated with trehalose,. This finding was disputed in 2019.
In 2021, the FDA accepted an Investigational New Drug (IND) application and granted fast track status for an injectable form of trehalose (SLS-005) as a potential treatment for spinocerebellar ataxia type 3 (SCA3). | 2 | Carbohydrates |
The storage of seeds in a temperature and moisture controlled environment. This technique is used for taxa with orthodox seeds that tolerate desiccation. Seed bank facilities vary from sealed boxes to climate controlled walk-in freezers or vaults. Taxa with recalcitrant seeds that do not tolerate desiccation are typically not held in seed banks for extended periods of time. | 0 | Cryobiology |
Active metabolism of glucose with production of bicarbonate has been demonstrated by Pettersson and Cohen.
Pettersson studies were on the metabolism of glucose and fatty acids by kidneys during 6 day hypothermic perfusion storage and he found that the kidneys consumed glucose at 4.4 μmol/g/day and fatty acids at 5.8 μmol/g/day. In Cohens study the best 8 day stored kidneys consumed glucose at the rate of 2.3 μmol/g/day and 4.9 μmol/g/day respectively which made it likely that they were using fatty acids at similar rates to Petterssons dogs' kidneys. The constancy of both the glucose consumption rate and the rate of bicarbonate production implied that no injury was affecting the glycolytic enzyme or carbonic anhydrase enzyme systems.
Lee showed that fatty acids were the preferred substrate of the rabbits kidney cortex at normothermic temperatures, and glucose the preferred substrate for the medullary cells which normally metabolise anaerobically. Abodeely showed that both fatty acids and glucose could be utilised by the outer medulla of the rabbits kidney but that glucose was used preferentially. At hypothermia the metabolic needs of the kidney are much reduced but measurable consumption of glucose, fatty acids and ketone bodies occurs. Horsburgh showed that lipid is utilised by hypothermic kidneys, with palmitate consumption being 0-15% of normal in the rat kidney cortex at 15 °C. Pettersson showed that, on a molar basis, glucose and fatty acids were metabolised by hypothermically perfused kidneys at about the same rates. The cortex of the hypothermic dog kidney was shown by Huang to lose lipid (35% loss of total lipid after 24 hours) unless oleate was added to the kidney perfusate. Huang commented that this loss could affect the structure of the cell and that the loss also suggested that the kidney was utilising fatty acid. In a later publication Huang showed that dog kidney cortex slices metabolised fatty acids, but not glucose, at 10 °C.
Even if the correct nutrients are provided, they may be lost by absorption into the tubing of the preservation system. Lee demonstrated that silicone rubber (a material used extensively in kidney preservation systems) absorbed 46% of a perfusate's oleic acid after 4 hours of perfusion. | 0 | Cryobiology |
Ex situ conservation, while helpful in humankinds efforts to sustain and protect our environment, is rarely enough to save a species from extinction. It is to be used as a last resort, or as a supplement to in situ conservation because it cannot recreate the habitat as a whole: the entire genetic variation of a species, its symbiotic counterparts, or those elements which, over time, might help a species adapt to its changing surroundings. Instead, ex situ conservation removes the species from its natural ecological contexts, preserving it under semi-isolated conditions whereby natural evolution and adaptation processes are either temporarily halted or altered by introducing the specimen to an unnatural habitat. In the case of cryogenic storage methods, the preserved specimens adaptation processes are (quite literally) frozen altogether. The downside to this is that, when re-released, the species may lack the genetic adaptations and mutations which would allow it to thrive in its ever-changing natural habitat.
Furthermore, ex situ conservation techniques are often costly, with cryogenic storage being economically infeasible in most cases since species stored in this manner cannot provide a profit but instead slowly drain the financial resources of the government or organization determined to operate them. Seedbanks are ineffective for certain plant genera with recalcitrant seeds that do not remain fertile for long periods of time. Diseases and pests foreign to the species, to which the species has no natural defense, may also cripple crops of protected plants in ex situ plantations and in animals living in ex situ breeding grounds. These factors, combined with the specific environmental needs of many species, some of which are nearly impossible to recreate by man, make ex situ conservation impossible for a great number of the world's endangered flora and fauna. | 0 | Cryobiology |
*Vorobiev E., Lebovka N., (2008). Electrotechnologies for Extraction from Food Plants and Biomaterials, . | 1 | Separation Processes |
When magnetoelectronic devices are operated at high frequencies, the generation of spin waves can be an important energy loss mechanism. Spin wave generation limits the linewidths and therefore the quality factors Q of ferrite components used in microwave devices. The reciprocal of the lowest frequency of the characteristic spin waves of a magnetic material gives a time scale for the switching of a device based on that material. | 3 | Magnetic Ordering |
Precondition for the applicability of sensor-based ore sorting is the presence of liberation at the particle size of interest. Before entering into sensor-based ore sorting testing procedures there is the possibility to assess the degree of liberation through the inspection of drill cores, hand-counting and washability analysis. The quantification of liberation does not include any process efficiencies, but gives an estimate of the possible sorting result and can thus be applied for desktop financial feasibility analysis.
Drill core analysis
Both for green-field and brown-field applications, inspection of drill core in combination with the grade distribution and mineralogical description is a good option for estimation of the liberation characteristics and the possible success of sensor-based ore sorting. In combination with the mining method and mine plan, an estimation of possible grade distribution in coarse particles can be done. | 1 | Separation Processes |
Until 2015, [http://csdb.glycoscience.ru/bacterial/index.html Bacterial Carbohydrate Structure Database] (BCSDB) and [http://csdb.glycoscience.ru/plant_fungal/index.html Plant&Fungal Carbohydrate Structure Database] (PFCSDB) databases existed in parallel. In 2015, they were joined into the single [http://csdb.glycoscience.ru/database/index.html Carbohydrate Structure Database] (CSDB). The development and maintenance of CSDB have been funded by [http://www.istc.int/en/ International Science and Technology Center] (2005-2007), [http://grants.extech.ru Russian Federation President grant program] (2005-2006), [http://www.rfbr.ru/rffi/eng Russian Foundation for Basic Research] (2005-2007,2012-2014,2015-2017,2018-2020), [https://www.dkfz.de/ Deutsches Krebsforschungszentrum] (short-term in 2006-2010), and [https://www.rscf.ru/en/ Russian Science Foundation] (2018-2020). | 2 | Carbohydrates |
Industrial mixer settlers are commonly used in the copper, nickel, uranium, lanthanide, and cobalt hydrometallurgy industries, when solvent extraction processes are applied.
They are also used in the Nuclear reprocessing field to separate and purify primarily Uranium and Plutonium, removing the fission product impurities.
In the multiple countercurrent process, multiple mixer settlers are installed with mixing and settling chambers located at alternating ends for each stage (since the outlet of the settling sections feed the inlets of the adjacent stage's mixing sections). Mixer-settlers are used when a process requires longer residence times and when the solutions are easily separated by gravity. They require a large facility footprint, but do not require much headspace, and need limited remote maintenance capability for occasional replacement of mixing motors. (Colven, 1956; Davidson, 1957)
The equipment units can be arrayed as:
*extraction (moving an ion of interest from an aqueous phase to an organic phase),
*washing (rinsing entrained aqueous contaminant out of an organic phase containing the ion of interest), and
*stripping (moving an ion of interest from an organic phase into an aqueous phase). | 1 | Separation Processes |
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. | 2 | Carbohydrates |
Lectins from legume plants, such as PHA or concanavalin A, have been used widely as model systems to understand the molecular basis of how proteins recognize carbohydrates, because they are relatively easy to obtain and have a wide variety of sugar specificities. The many crystal structures of legume lectins have led to a detailed insight of the atomic interactions between carbohydrates and proteins.
Legume seed lectins have been studied for their insecticidal potential and have shown harmful effects for the development of pest. | 2 | Carbohydrates |
Nutritionists often refer to carbohydrates as either simple or complex. However, the exact distinction between these groups can be ambiguous. The term complex carbohydrate was first used in the U.S. Senate Select Committee on Nutrition and Human Needs publication Dietary Goals for the United States (1977) where it was intended to distinguish sugars from other carbohydrates (which were perceived to be nutritionally superior). However, the report put "fruit, vegetables and whole-grains" in the complex carbohydrate column, despite the fact that these may contain sugars as well as polysaccharides. This confusion persists as today some nutritionists use the term complex carbohydrate to refer to any sort of digestible saccharide present in a whole food, where fiber, vitamins and minerals are also found (as opposed to processed carbohydrates, which provide energy but few other nutrients). The standard usage, however, is to classify carbohydrates chemically: simple if they are sugars (monosaccharides and disaccharides) and complex if they are polysaccharides (or oligosaccharides).
In any case, the simple vs. complex chemical distinction has little value for determining the nutritional quality of carbohydrates. Some simple carbohydrates (e.g. fructose) raise blood glucose rapidly, while some complex carbohydrates (starches), raise blood sugar slowly. The speed of digestion is determined by a variety of factors including which other nutrients are consumed with the carbohydrate, how the food is prepared, individual differences in metabolism, and the chemistry of the carbohydrate. Carbohydrates are sometimes divided into "available carbohydrates", which are absorbed in the small intestine and "unavailable carbohydrates", which pass to the large intestine, where they are subject to fermentation by the gastrointestinal microbiota.
The USDAs Dietary Guidelines for Americans 2010' call for moderate- to high-carbohydrate consumption from a balanced diet that includes six one-ounce servings of grain foods each day, at least half from whole grain sources and the rest are from enriched.
The glycemic index (GI) and glycemic load concepts have been developed to characterize food behavior during human digestion. They rank carbohydrate-rich foods based on the rapidity and magnitude of their effect on blood glucose levels. Glycemic index is a measure of how quickly food glucose is absorbed, while glycemic load is a measure of the total absorbable glucose in foods. The insulin index is a similar, more recent classification method that ranks foods based on their effects on blood insulin levels, which are caused by glucose (or starch) and some amino acids in food. | 2 | Carbohydrates |
A spin ice is a magnetic substance that does not have a single minimal-energy state. It has magnetic moments (i.e. "spin") as elementary degrees of freedom which are subject to frustrated interactions. By their nature, these interactions prevent the moments from exhibiting a periodic pattern in their orientation down to a temperature much below the energy scale set by the said interactions. Spin ices show low-temperature properties, residual entropy in particular, closely related to those of common crystalline water ice. The most prominent compounds with such properties are dysprosium titanate (DyTiO) and holmium titanate (HoTiO). The orientation of the magnetic moments in spin ice resembles the positional organization of hydrogen atoms (more accurately, ionized hydrogen, or protons) in conventional water ice (see figure 1).
Experiments have found evidence for the existence of deconfined magnetic monopoles in these materials, with properties resembling those of the hypothetical magnetic monopoles postulated to exist in vacuum. | 3 | Magnetic Ordering |
The property by which some neurons do not return to their basal conditions from a stimulated condition immediately after removal of the stimulus is an example of hysteresis. | 3 | Magnetic Ordering |
The dianion, methanediolate, is believed to be an intermediate in the crossed Cannizzaro reaction.
Gaseous methanediols can be generated by electron irradiation and sublimation of a mixture of methanol and oxygen ices.
Methanediol is believed to occur as an intermediate in the decomposition of carbonyl compounds in the atmosphere, and as a product of ozonolysis on these compounds. | 2 | Carbohydrates |
In (forward) osmosis, the solvent moves from an area of low solute concentration (high water potential), through a membrane, to an area of high solute concentration (low water potential). The driving force for the movement of the solvent is the reduction in the Gibbs free energy of the system in which the difference in solvent concentration between the sides of a membrane is reduced. This is called osmotic pressure. It reduces as the solvent moves into the more concentrated solution. Applying an external pressure to reverse the natural flow of pure solvent, thus, is reverse osmosis. The process is similar to other membrane technology applications.
RO differs from filtration in that the mechanism of fluid flow is reversed, as the solvent crosses membrane, leaving the solute behind. The predominant removal mechanism in membrane filtration is straining, or size exclusion, where the pores are 0.01 micrometers or larger, so the process can theoretically achieve perfect efficiency regardless of parameters such as the solution's pressure and concentration. RO instead involves solvent diffusion across a membrane that is either nonporous or uses nanofiltration with pores 0.001 micrometers in size. The predominant removal mechanism is from differences in solubility or diffusivity, and the process is dependent on pressure, solute concentration, and other conditions.
RO requires pressure between 2–17 bar (30–250 psi) for fresh and brackish water, and 40–82 bar (600–1200 psi) for seawater. Seawater has around 27 bar (390 psi) natural osmotic pressure that must be overcome.
Membrane pore sizes vary from 0.1 to 5,000 nm. Particle filtration removes particles of 1 µm or larger. Microfiltration removes particles of 50 nm or larger. Ultrafiltration removes particles of roughly 3 nm or larger. Nanofiltration removes particles of 1 nm or larger. RO is in the final category of membrane filtration, hyperfiltration, and removes particles larger than 0.1 nm. | 1 | Separation Processes |
Lasers have been used to indirectly generate non-coherent extreme UV (E‑UV) radiation at 13.5 nm for extreme ultraviolet lithography. The E‑UV is not emitted by the laser, but rather by electron transitions in an extremely hot tin or xenon plasma, which is excited by an excimer laser. This technique does not require a synchrotron, yet can produce UV at the edge of the X‑ray spectrum. Synchrotron light sources can also produce all wavelengths of UV, including those at the boundary of the UV and X‑ray spectra at 10 nm. | 4 | Ultraviolet Radiation |
Machine perfusion (MP) is a technique used in organ transplantation as a means of preserving the organs which are to be transplanted.
Machine perfusion has various forms and can be categorised according to the temperature of the perfusate: cold (4 °C) and warm (37 °C). Machine perfusion has been applied to renal transplantation, liver transplantation and lung transplantation. It is an alternative to static cold storage (SCS). | 0 | Cryobiology |
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. | 0 | Cryobiology |
Sensor-based sorting, is an umbrella term for all applications in which particles are detected using a sensor technique and rejected by an amplified mechanical, hydraulic or pneumatic process.
The technique is generally applied in mining, recycling and food processing and used in the particle size range between . Since sensor-based sorting is a single particle separation technology, the throughput is proportional to the average particle size and weight fed onto the machine. | 1 | Separation Processes |
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. | 3 | Magnetic Ordering |
In the United States, sperm banks maintain lists or catalogs of donors which provide basic information about the donor such as racial origin, skin color, height, weight, color of eyes, and blood group. Some of these catalogs are available for browsing on the Internet, while others are made available to patients only when they apply to a sperm bank for treatment. Some sperm banks make additional information about each donor available for an additional fee, and others make additional basic information known to children produced from donors when those children reach the age of 18. Some clinics offer "exclusive donors" whose sperm is used to produce pregnancies for only one recipient woman. How accurate this is, or can be, is not known, and neither is it known whether the information produced by sperm banks, or by the donors themselves, is true. Many sperm banks will, however, carry out whatever checks they can to verify the information they request, such as checking the identity of the donor and contacting his own doctor to verify medical details.
In the United Kingdom, most donors are anonymous at the point of donation and recipients can see only non-identifying information about their donor (height, weight, ethnicity etc.). Donors need to provide identifying information to the clinic and clinics will usually ask the donors doctor to confirm any medical details they have been given. Donors are asked to provide a pen portrait of themselves which is held by the HFEA and can be obtained by the adult conceived from the donation at the age of 18, along with identifying information such as the donors name and last known address. Known donation is permitted and it is not uncommon for family or friends to donate to a recipient couple.
Qualities that potential recipients typically prefer in donors include the donors being tall, college educated, and with a consistently high sperm count.
A review came to the result that 68% of donors had given information to the clinical staff regarding physical characteristics and education but only 16% had provided additional information such as hereditary aptitudes and temperament or character. | 0 | Cryobiology |
*1.[https://web.archive.org/web/20060118094514/http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=5039 Nanotechnology: Molecular Speculations on Global Abundance]
*2.[https://www.amazon.com/gp/product/354067215X Functional MRI] | 0 | Cryobiology |
Wheat germ agglutinin, a plant lectin, is able to recognize terminal GlcNAc residues and is thus often used for detection of O-GlcNAc. This lectin has been applied in lectin affinity chromatography for the enrichment and detection of O-GlcNAc. | 2 | Carbohydrates |
* Molecular structures of glycans, glycopolymers and glycoconjugates: primary structure, aglycon information, polymerization degree and class of molecule. Structural scope includes molecules composed of residues (monosaccharides, alditols, amino acids, fatty acids etc.) linked by glycosidic, ester, amidic, ketal, phospho- or sulpho-diester bonds, in which at least one residue is a monosaccharide or its derivative.
* Bibliography associated with structures: imprint data, keywords, abstracts, IDs in bibliographic databases
* Biological context of structures: associated taxon, strain, serogroup, host organism, disease information. The covered domains are: prokaryotes, plants, fungi and selected pathogenic unicellular metazoa. The database contains only glycans originating from these domains or obtained by chemical modification of such glycans.
* Assigned NMR spectra and experimental conditions.
* Glycosyltransferases associated with taxons: gene and enzyme identifiers, full structures, donor and substrates, methods used to prove enzymatic activity, trustworthiness level.
* References to other databases
* Other data collected from original publications
* Conformation maps of disaccharides derived from molecular dynamics simulations. | 2 | Carbohydrates |
Since the U.S. Food and Drug Administration issued a rule in 2001 requiring that virtually all fruit and vegetable juice producers follow HACCP controls, and mandating a 5-log reduction in pathogens, UVGI has seen some use in sterilization of juices such as fresh-pressed. | 4 | Ultraviolet Radiation |
As for any other physical separation process, liberation is pre-requisite for possible separation. Liberation characteristics are well known and relatively easy to study for particulate lots in smaller size ranges, e.g. flotation feed and products. The analysis is essential for understanding the possible results of physical separation and relatively easy to conduct in laboratory on a couple of dozens of grams of sample which can be studied using optical methods or such as the QEMSCAN.
For larger particles above it is widely known for applications that are treated using density separation methods, such as coal or iron ore. Here, the washability analysis can be conducted on sample masses up to 10 tonnes in equipped laboratories. For sensor-based sorting, where laboratory methods can only tell about the liberation characteristics where the describing feature is the density (e.g. iron ore, coal), hand counting, single-particle tests and bulk tests can reveal the liberation characteristics of a bulk material: Hereby, only single particle tests reveal the true liberation, while hand counting and bulk testing give a result which also incorporates the separation efficiency of the type of analysis. More information on the testing procedures used in technical feasibility evaluation can be found in the respective chapter. | 1 | Separation Processes |
Many microorganisms living in sea ice possess AFPs that belong to a single family. The diatoms Fragilariopsis cylindrus and F. curta play a key role in polar sea ice communities, dominating the assemblages of both platelet layer and within pack ice. AFPs are widespread in these species, and the presence of AFP genes as a multigene family indicates the importance of this group for the genus Fragilariopsis. AFPs identified in F. cylindrus belong to an AFP family which is represented in different taxa and can be found in other organisms related to sea ice (Colwellia spp., Navicula glaciei, Chaetoceros neogracile and Stephos longipes and Leucosporidium antarcticum) and Antarctic inland ice bacteria (Flavobacteriaceae), as well as in cold-tolerant fungi (Typhula ishikariensis, Lentinula edodes and Flammulina populicola).
Several structures for sea ice AFPs have been solved. This family of proteins fold into a beta helix that form a flat ice-binding surface. Unlike the other AFPs, there is not a singular sequence motif for the ice-binding site.
AFP found from the metagenome of the ciliate Euplotes focardii and psychrophilic bacteria has an efficient ice re-crystallization inhibition ability. 1 μM of Euplotes focardii consortium ice-binding protein (EfcIBP) is enough for the total inhibition of ice re-crystallization in –7.4 °C temperature. This ice-recrystallization inhibition ability helps bacteria to tolerate ice rather than preventing the formation of ice. EfcIBP produces also thermal hysteresis gap, but this ability is not as efficient as the ice-recrystallization inhibition ability. EfcIBP helps to protect both purified proteins and whole bacterial cells in freezing temperatures. Green fluorescent protein is functional after several cycles of freezing and melting when incubated with EfcIBP. Escherichia coli survives longer periods in 0 °C temperature when the efcIBP gene was inserted to E. coli genome. EfcIBP has a typical AFP structure consisting of multiple beta-sheets and an alpha-helix. Also, all the ice-binding polar residues are at the same site of the protein. | 0 | Cryobiology |
Salting out (also known as salt-induced precipitation, salt fractionation, anti-solvent crystallization, precipitation crystallization, or drowning out) is a purification technique that utilizes the reduced solubility of certain molecules in a solution of very high ionic strength. Salting out is typically used to precipitate large biomolecules, such as proteins or DNA. Because the salt concentration needed for a given protein to precipitate out of the solution differs from protein to protein, a specific salt concentration can be used to precipitate a target protein. This process is also used to concentrate dilute solutions of proteins. Dialysis can be used to remove the salt if needed. | 1 | Separation Processes |
Long before a deeper understanding of their numerous biological functions, the plant lectins, also known as phytohemagglutinins, were noted for their particularly high specificity for foreign glycoconjugates (e.g., those of fungi and animals) and used in biomedicine for blood cell testing and in biochemistry for fractionation.
Although they were first discovered more than 100 years ago in plants, now lectins are known to be present throughout nature. The earliest description of a lectin is believed to have been given by Peter Hermann Stillmark in his doctoral thesis presented in 1888 to the University of Dorpat. Stillmark isolated ricin, an extremely toxic hemagglutinin, from seeds of the castor plant (Ricinus communis).
The first lectin to be purified on a large scale and available on a commercial basis was concanavalin A, which is now the most-used lectin for characterization and purification of sugar-containing molecules and cellular structures. The legume lectins are probably the most well-studied lectins. | 2 | Carbohydrates |
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). | 4 | Ultraviolet Radiation |
Generally, the main process in a rotary vacuum drum filter is continuous filtration whereby solids are separated from liquids through a filter medium by a vacuum. The filter cloth is one of the most important components on a filter and is typically made of weaving polymer yarns. The best selection of cloth can increase the performance of filtration. Initially, slurry is pumped into the trough and as the drum rotates, it is partially submerged in the slurry. The vacuum draws liquid and air through the filter media and out the shaft hence forming a layer of cake. An agitator is used to regulate the slurry if the texture is coarse and it is settling rapidly. Solids that are trapped on the surface of the drum are washed and dried after 2/3 of revolution, removing all the free moisture.
During the washing stage, the wash liquid can either be poured onto the drum or sprayed on the cake. Cake pressing is optional but its advantages are preventing cake cracking and removing more moisture. Cake discharge is when all the solids are removed from the surface of the cake by a scraper blade, leaving a clean surface as drum re-enters the slurry. There are a few types of discharge which are scraper, roller, string, endless belt and pre coat. The filtrate and air flow through internal pipes, valve and into the vacuum receiver where the separation of liquid and gas occurs producing a clear filtrate. Pre coat filtration is an ideal method to produce a high clarity of filtrate. Basically, the drum surface is pre coated with a filter aid such as diatomaceous earth (DE) or perlite to improve filtration and increase cake permeability. It then undergoes the same process cycle as the conventional rotary vacuum drum filter however, pre coat filtration uses a higher precision blade to scrape off the cake.
The filter is assessed by the size of the drum or filter area and its possible output. Typically, the output is in the units of pounds per hour of dry solids per square foot of filter area. The size of the auxiliary parts depends on the area of the filter and the type of usage. Rotary vacuum filters are flexible in handling variety of materials therefore the estimated solids yield from 5 to 200 pounds per hour per square foot. For pre coat discharge, the solid output is approximately 2 to 40 gallons per hour per square foot. Filtration efficiencies can also be improved in terms dryness of filter cake by significantly preventing filtrate liquid from getting stuck in the filter drum during filtration phase. Usage of multiple filters for example, running 3 filter units instead of 2 units yields a thicker cake hence, producing a clearer filtrate. This becomes beneficial in terms of production cost and also quality. | 1 | Separation Processes |
There are various expansions or additional techniques that can be applied in IVF, which are usually not necessary for the IVF procedure itself, but would be virtually impossible or technically difficult to perform without concomitantly performing methods of IVF. | 0 | Cryobiology |
All cells require ATP as an energy source for their metabolic activity. The kidney is damaged by anoxia when kidney cortical cells are unable to generate sufficient ATP under anaerobic conditions to meet the needs of the cells. When excising a kidney some anoxia is inevitable in the interval between dividing the renal artery and cooling the kidney. It has been shown by Bergstrom that 50% of a dogs kidneys cortical cells ATP content is lost within 1 minute of clamping the renal artery, and similar results were found by Warnick in whole mice kidneys, with a fall in cellular ATP by 50% after about 30 seconds of warm anoxia. Warnick and Bergstrom also showed that cooling the kidney immediately after removal markedly reduced any further ATP loss. When these non warm-injured kidneys were perfused with oxygenated hypothermic plasma, ATP levels were reduced by 50% after 24-hour storage and, after 48 hours, mean tissue ATP levels were a little higher than this indicating that synthesis of ATP had occurred. Pegg has shown that rabbit kidneys can resynthesize ATP after a period of perfusion storage following warm injury, but no resynthesis occurred in non warm-injured kidneys.
Warm anoxia can also occur during reimplantation of the kidney after storage. Lannon showed, by measurements of succinate metabolism, how the kidney was more sensitive to a period of warm hypoxia occurring after storage than to the same period of warm hypoxia occurring immediately prior to storage. | 0 | Cryobiology |
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. | 4 | Ultraviolet Radiation |
A major issue is how many embryos should be transferred, since placement of multiple embryos carries a risk of multiple pregnancy. While the past physicians placed multiple embryos to increase the chance of pregnancy, this approach has fallen out of favor. Professional societies, and legislatures in many countries, have issued guidelines or laws to curtail the practice. There is low to moderate evidence that making a double embryo transfer during one cycle achieves a higher live birth rate than a single embryo transfer; but making two single embryo transfers in two cycles has the same live birth rate and would avoid multiple pregnancies.
The appropriate number of embryos to be transferred depends on the age of the woman, whether it is the first, second or third full IVF cycle attempt and whether there are top-quality embryos available. According to a guideline from The National Institute for Health and Care Excellence (NICE) in 2013, the number of embryos transferred in a cycle should be chosen as in following table: | 0 | Cryobiology |
DSSCs are currently the most efficient third-generation (2005 Basic Research Solar Energy Utilization 16) solar technology available. Other thin-film technologies are typically between 5% and 13%, and traditional low-cost commercial silicon panels operate between 14% and 17%. This makes DSSCs attractive as a replacement for existing technologies in "low density" applications like rooftop solar collectors, where the mechanical robustness and light weight of the glass-less collector is a major advantage. They may not be as attractive for large-scale deployments where higher-cost higher-efficiency cells are more viable, but even small increases in the DSSC conversion efficiency might make them suitable for some of these roles as well.
There is another area where DSSCs are particularly attractive. The process of injecting an electron directly into the TiO is qualitatively different from that occurring in a traditional cell, where the electron is "promoted" within the original crystal. In theory, given low rates of production, the high-energy electron in the silicon could re-combine with its own hole, giving off a photon (or other form of energy) which does not result in current being generated. Although this particular case may not be common, it is fairly easy for an electron generated by another atom to combine with a hole left behind in a previous photoexcitation.
In comparison, the injection process used in the DSSC does not introduce a hole in the TiO, only an extra electron. Although it is energetically possible for the electron to recombine back into the dye, the rate at which this occurs is quite slow compared to the rate that the dye regains an electron from the surrounding electrolyte. Recombination directly from the TiO to species in the electrolyte is also possible although, again, for optimized devices this reaction is rather slow. On the contrary, electron transfer from the platinum coated electrode to species in the electrolyte is necessarily very fast.
As a result of these favorable "differential kinetics", DSSCs work even in low-light conditions. DSSCs are therefore able to work under cloudy skies and non-direct sunlight, whereas traditional designs would suffer a "cutout" at some lower limit of illumination, when charge carrier mobility is low and recombination becomes a major issue. The cutoff is so low they are even being proposed for indoor use, collecting energy for small devices from the lights in the house.
A practical advantage which DSSCs share with most thin-film technologies, is that the cell's mechanical robustness indirectly leads to higher efficiencies at higher temperatures. In any semiconductor, increasing temperature will promote some electrons into the conduction band "mechanically". The fragility of traditional silicon cells requires them to be protected from the elements, typically by encasing them in a glass box similar to a greenhouse, with a metal backing for strength. Such systems suffer noticeable decreases in efficiency as the cells heat up internally. DSSCs are normally built with only a thin layer of conductive plastic on the front layer, allowing them to radiate away heat much easier, and therefore operate at lower internal temperatures. | 4 | Ultraviolet Radiation |
Conventional cryoprotectants are glycols (alcohols containing at least two hydroxyl groups), such as ethylene glycol , propylene glycol and glycerol. Ethylene glycol is commonly used as automobile antifreeze; while propylene glycol has been used to reduce ice formation in ice cream. Dimethyl sulfoxide (DMSO) is also regarded as a conventional cryoprotectant. Glycerol and DMSO have been used for decades by cryobiologists to reduce ice formation in sperm, oocytes, and embryos that are cold-preserved in liquid nitrogen. Cryoconservation of animal genetic resources is a practice that involves conventional cryoprotectants to store genetic material with the intention of future revival. Trehalose is non-reducing sugar produced by yeasts and insects in copious amounts. Its use as a cryoprotectant in commercial systems has been patented widely. | 0 | Cryobiology |
The purpose of static micromagnetics is to solve for the spatial distribution of the magnetization M at equilibrium. In most cases, as the temperature is much lower than the Curie temperature of the material considered, the modulus |M| of the magnetization is assumed to be everywhere equal to the saturation magnetization M. The problem then consists in finding the spatial orientation of the magnetization, which is given by the magnetization direction vector m = M/M, also called reduced magnetization.
The static equilibria are found by minimizing the magnetic energy,
subject to the constraint |M|=M or |m|=1.
The contributions to this energy are the following: | 3 | Magnetic Ordering |
The absence of fructokinase results in the inability to phosphorylate fructose to fructose-1-phosphate within the cell. As a result, fructose is neither trapped within the cell nor directed toward its metabolism. Free fructose concentrations in the liver increase and fructose is free to leave the cell and enter plasma. This results in an increase in plasma concentration of fructose, eventually exceeding the kidneys' threshold for fructose reabsorption resulting in the appearance of fructose in the urine. Essential fructosuria is a benign asymptomatic condition. | 2 | Carbohydrates |
Based on the statistics presented in earlier discussions, there is controversy with regard to a perceived lack of diversity within the donor sperm pool of many sperm banks. This includes, but is not limited to, height requirements implemented by some sperm banks. As a result, it is alleged that potential sperm recipients often encounter very limited sperm donor pool options. Lack of diversity results in very limited choices especially among ethnic minorities within the United States. Whenever an individual chooses to specify their preferred donor background, the number of available options (sperm donors that meet the particular individuals criteria) can dwindle down to the low single digits. Scott Brown from California Cryobank admitted: "We dont get as many minority applicants as we [would] like." Even after numerous attempts to reach out to numerous ethnic communities, the response can be nearly nonexistent.
At the California Cryoback, Brown mentions that one out of 100 would be able to become final sperm donor while Ottey from the Fairfax Cryobank mentions one out of 200 would be able to become ultimate sperm donors. In addition, locations of the California Cryobank are in Los Angeles, Los Altos, California; mid-Manhattan, and Cambridge Massachusetts. These locations are known to have a population with higher socioeconomic latitude and being more likely to afford the services. Moreover, one of the requirements includes the potential sperm donor to be able to live nearby the sperm bank in order to provide samples once to twice a month for at least a term of six months. This could create potential barriers for populations who are at socioeconomic disadvantage and do not have their own forms of transportation; often having to rely on multiple forms of public transportation to reach certain places. This factor could cause a significant decrease in the sperm donor pool and less diverse availability for sperm recipients.
Some controversy stems from the fact that donors father children for others, in the majority of cases, for single people or same-sex couples, but usually take no part in the upbringing of such children. The issue of sperm banks providing fertility services to single women and coupled lesbians so that they can have their own biological children by a donor is itself, often controversial in some jurisdictions but in many countries where sperm banks operate, this group form the main body of recipients. Donors usually do not have a say in who may be a recipient of their sperm.
Another controversy centers around the use of sperm posthumously, or after the death of the sperm donor, as pioneered by California Cryobank. Within the United States, there were differences when it came to a child conceived after the fathers death and the eligibility for survivors benefits. Under California law, there was one court case (Vernoff vs. Astrue) in which the mothers child (conceived after the fathers death) was not eligible for the survivors benefits. However, Arizona courts had a different approach when it came to children who were born after fathers death that the children are eligible for the survivors benefits. There were numerous other stories of similar situations across different states in the United States and even the United Kingdom. Canada, France, Germany, and Sweden do not permit the retrieval use of sperm posthumously. | 0 | Cryobiology |
Cold hardening has also been observed in insects such as the fruit fly and diamondback moth. The insects use rapid cold hardening to protect against cold shock during overwintering periods. Overwintering insects stay awake and active through the winter while non-overwintering insects migrate or die. Rapid cold hardening can be experienced during short periods of undesirable temperatures, such as cold shock in environment temperature, as well as the common cold months. The buildup of cryoprotective compounds is the reason that insects can experience cold hardening. Glycerol is a cryoprotective substance found within these insects capable of overwintering. Through testing, glycerol requires interactions with other cell components within the insect in order to decrease the body's permeability to the cold. When an insect is exposed to these cold temperatures, glycerol rapidly accumulates. Glycerol is known as a non-ionic kosmotrope forming powerful hydrogen bonds with water molecules. The hydrogen bonds in the glycerol compound compete with the weaker bonds between the water molecules causing an interruption in the makeup of ice formation. This chemistry found within the glycerol compound and reaction between water has been used as an antifreeze in the past, and can be seen here when concerning cold hardening. Proteins also play a large role in the cryoprotective compounds that increase ability to survive the cold hardening process and environmental change. Glycogen phosphorylase (GlyP) has been a key protein found during testing to increase in comparison to a controlled group not experiencing the cold hardening. Once warmer temperatures are observed the process of acclimation begins, and the increased glycerol along with other cryoprotective compounds and proteins are also reversed. There is a rapid cold hardening capacity found within certain insects that suggests not all insects can survive a long period of overwintering. Non-diapausing insects can sustain brief temperature shocks but often have a limit to what they can handle before the body can no longer produce enough cryoprotective components.
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Inclusive to the cold hardening process being beneficial for insects survival during cold temperatures, it also helps improve the organisms performance. Rapid cold hardening (RCH) is one of the fastest cold temperature responses recorded. This process allows an insect to instantly adapt to the severe weather change without compromising function. The Drosophila melanogaster' (common fruit fly) is a frequently experimented insect involving cold hardening. A proven example of RCH enhancing organisms performance comes from courting and mating within the fruit fly. It has been tested that the fruit fly mated more frequently once RCH has commenced in relation to a controlled insect group not experiencing RCH. Most insects experiencing extended cold periods are observed to modify the membrane lipids within the body. Desaturation of fatty acids are the most commonly seen modification to the membrane. When the fruit fly was observed under the stressful climate the survival rate increased in comparison to the fly prior to cold hardening.
In addition to testing on the common fruit fly, Plutella xylostella (diamondback moth) also has been widely studied for its significance in cold hardening. While this insect also shows an increase in glycerol and similar cryoprotective compounds, it also shows an increase in polyols. These compounds are specifically linked to cryoprotective compounds designed to withstand cold hardening. The polyol compound is freeze-susceptible and freeze tolerant. Polyols simply act as a barrier within the insect body by preventing intracellular freezing by restricting the extracellular freezing likely to happen in overwintering periods. During the larval stage of the diamondback moth, the significance of glycerol was tested again for validity. The lab injected the larvae with added glycerol and in turn proved that glycerol is a major factor in survival rate when cold hardening. The cold tolerance is directly proportional to the buildup of glycerol during cold hardening.
Cold hardening of insects improves the survival rate of the species and improves function. Once environmental temperature begins to warm up above freezing, the cold hardening process is reversed and the glycerol and cryoprotective compounds decrease within the body. This also reverts the function of the insect to pre-cold hardening activity. | 0 | Cryobiology |
Polyolefins such as polyethylene and polypropylene are susceptible to photo-oxidation and around 70% of light stabilizers produced world-wide are used in their protection, despite them representing only around 50% of global plastic production. Aliphatic hydrocarbons can only adsorb high energy UV-rays with a wavelength below ~250 nm, however the Earth’s atmosphere and ozone layer screen out such rays, with the normal minimum wavelength being 280–290 nm.
The bulk of the polymer is therefore photo-inert and degradation is instead attributed to the presence of various impurities, which are introduced during the manufacturing or processing stages. These include hydroperoxide and carbonyl groups, as well as metal salts such as catalyst residues.
All of these species act as photoinitiators.
The organic hydroperoxide and carbonyl groups are able to absorb UV light above 290 nm whereupon they undergo photolysis to generate radicals. Metal impurities act as photocatalysts, although such reactions can be complex. It has also been suggested that polymer-O charge-transfer complexes are involved. Initiation generates radical-carbons on the polymer chain, sometimes called macroradicals (P•).
Chain initiation
Chain propagation
Chain branching
Termination
Classically the carbon-centred macroradicals (P•) rapidly react with oxygen to form hydroperoxyl radicals (POO•), which in turn abstract an H atom from the polymer chain to give a hydroperoxide (POOH) and a fresh macroradical. Hydroperoxides readily undergo photolysis to give an alkoxyl macroradical radical (PO•) and a hydroxyl radical (HO•), both of which may go on to form new polymer radicals via hydrogen abstraction. Non-classical alternatives to these steps have been proposed. The alkoxyl radical may also undergo beta scission, generating a acyl-ketone and macroradical. This is considered to be the main cause of chain breaking in polypropylene.
Secondary hydroperoxides can also undergo an intramolecular reaction to give a ketone group, although this is limited to polyethylene.
The ketones generated by these processes are themselves photo-active, although much more weakly. At ambient temperatures they undergo Type II Norrish reactions with chain scission. They may also absorb UV-energy, which they can then transfer to O, causing it to enter its highly reactive singlet state. Singlet oxygen is a potent oxidising agent can go on to form cause further degradation. | 4 | Ultraviolet Radiation |
Cryoprotectants are also used to preserve foods. These compounds are typically sugars that are inexpensive and do not pose any toxicity concerns. For example, many (raw) frozen chicken products contain a sucrose and sodium phosphates solution in water. | 0 | Cryobiology |
If a coil of turns with a surface through which passes a current of excitation is immersed in a magnetic field collinear with the axis of the coil, a superparamagnetic material is deposited inside the coil.
The electromotive force to the terminals of a winding of the coil, , is given by the formula:
where is the magnetic induction given by the equation:
In the absence of magnetic material,
and
Differentiating this expression, the frequency of the voltage is the same as the excitation current or the magnetic field .
In the presence of superparamagnetic material, neglecting the higher terms of the Taylor expansion, we obtain for B:
A new derivation of the first term of the equation provides frequency voltage components of the stream of excitement or the magnetic field .
The development of the second term multiplies the frequency components in which intermodular frequencies start components and generate their linear combinations. The non-linearity of the superparamagnetic material acts as a frequency mixer.
Calling the total magnetic field within the coil at the abscissa, integrating the above induction coil along the abscissa between 0 and and differentiating with respect to obtains:
with
The conventional terms of self-inductance and Rogowski effect are found in both the original frequencies. The third term is due to the Néel effect; it reports the intermodulation between the excitation current and the external field.
When the excitation current is sinusoidal, the effect is Néel characterized by the appearance of a second harmonic carrying the information flow field: | 3 | Magnetic Ordering |
The main durations of embryo culture are until cleavage stage (day two to four after co-incubation) or the blastocyst stage (day five or six after co-incubation). Embryo culture until the blastocyst stage confers a significant increase in live birth rate per embryo transfer, but also confers a decreased number of embryos available for transfer and embryo cryopreservation, so the cumulative clinical pregnancy rates are increased with cleavage stage transfer. Transfer day two instead of day three after fertilisation has no differences in live birth rate. There are significantly higher odds of preterm birth (odds ratio 1.3) and congenital anomalies (odds ratio 1.3) among births having from embryos cultured until the blastocyst stage compared with cleavage stage. | 0 | Cryobiology |
The key concept is that larger cells tend to stay within the flowing buffer solution while smaller cells will be washed away follow the buffer solution (different sedimentation property within the buffer solution), and cells will have different sedimentation properties in different cell cycle stages.
The basic principle of separating the cells inside CCE is the balance between centripetal and the counter flow drag force. When the cells enter the elutriation chamber, all the cells will stay at the outer edge of the chamber due to centrifugal force. Then when the flow rate of the buffer solution increases, the solution tends to push the cells towards the middle of the CCE. When the counter flow drag force outweighs the centripetal force, particles will be driven by the net force and leave the chamber. Smaller particles are able to leave the chamber at lower flow rates. In contrast, larger particles will stay within the elutriation chamber. Therefore, buffer flow rate can be used to control size sorting within the elutriation chamber. | 1 | Separation Processes |
In chemical separation terminology, the raffinate (from French raffiner, to refine) is a product which has had a component or components removed. The product having the removed materials is referred to as the extract. For example, in solvent extraction, the raffinate is the liquid stream which remains after solutes from the original liquid are removed through contact with an immiscible liquid. In metallurgy, raffinating refers to a process in which impurities are removed from liquid material.
In pressure swing adsorption the raffinate refers to the gas which is not adsorbed during the high pressure stage. The species which is desorbed from the adsorbent at low pressure may be called the "extract" product. | 1 | Separation Processes |
Concanavalin A and other commercially available lectins have been used widely in affinity chromatography for purifying glycoproteins.
In general, proteins may be characterized with respect to glycoforms and carbohydrate structure by means of affinity chromatography, blotting, affinity electrophoresis, and affinity immunoelectrophoreis with lectins, as well as in microarrays, as in evanescent-field fluorescence-assisted lectin microarray. | 2 | Carbohydrates |
When beer at typical concentration is subjected to reverse osmosis, both water and alcohol pass across the membrane more readily than other components, leaving a "beer concentrate". The concentrate is then diluted with fresh water to restore the non-volatile components to their original intensity. | 1 | Separation Processes |
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. | 0 | Cryobiology |
It is usually recommended not to declare a person dead until their body is warmed to a near normal body temperature of greater than , since extreme hypothermia can suppress heart and brain function. This is summarized in the common saying "Youre not dead until youre warm and dead." Exceptions include if there are obvious fatal injuries or the chest is frozen so that it cannot be compressed. If a person was buried in an avalanche for more than 35 minutes and is found with a mouth packed full of snow without a pulse, stopping early may also be reasonable. This is also the case if a person's blood potassium is greater than 12 mmol/L.
Those who are stiff with pupils that do not move may survive if treated aggressively. Survival with good function also occasionally occurs even after the need for hours of CPR. Children who have near-drowning accidents in water near can occasionally be revived, even over an hour after losing consciousness. The cold water lowers the metabolism, allowing the brain to withstand a much longer period of hypoxia. While survival is possible, mortality from severe or profound hypothermia remains high despite optimal treatment. Studies estimate mortality at between 38% and 75%.
In those who have hypothermia due to another underlying health problem, when death occurs it is frequently from that underlying health problem. | 0 | Cryobiology |
Histidine-tryptophan-ketoglutarate, or Custodiol HTK solution, is a high-flow, low-potassium preservation solution used for organ transplantation. The solution was initially developed by Hans-Jürgen Bretschneider.
HTK solution is intended for perfusion and flushing of donor liver, kidney, heart, lung and pancreas prior to removal from the donor and for preserving these organs during hypothermic storage and transport to the recipient. HTK solution is based on the principle of inactivating organ function by withdrawal of extracellular sodium and calcium, together with intensive buffering of the extracellular space by means of histidine/histidine hydrochloride, so as to prolong the period during which the organs will tolerate interruption of oxygenated blood. The composition of HTK is similar to that of intracellular fluid. All of the components of HTK occur naturally in the body. The osmolarity of HTK is 310 mOsm/L. | 0 | Cryobiology |
Site-directed mutagenesis of O-GlcNAc-modified serine or threonine residues to alanine may be used to evaluate the function of O-GlcNAc at specific residues. As alanines side chain is a methyl group and is thus not able to act as an O-GlcNAc site, this mutation effectively permanently removes O-GlcNAc at a specific residue. While serine/threonine phosphorylation may be modeled by mutagenesis to aspartate or glutamate, which have negatively charged carboxylate side chains, none of the 20 canonical amino acids sufficiently recapitulate the properties of O-GlcNAc. Mutagenesis to tryptophan has been used to mimic the steric bulk of O-GlcNAc, though tryptophan is much more hydrophobic than O-GlcNAc. Mutagenesis may also perturb other post-translational modifications, e.g., if a serine is alternatively phosphorylated or O-GlcNAcylated, alanine mutagenesis permanently eliminates the possibilities of both phosphorylation and O'-GlcNAcylation. | 2 | Carbohydrates |
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. | 2 | Carbohydrates |
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. | 1 | Separation Processes |
The Latin term in vitro, meaning "in glass", is used because early biological experiments involving cultivation of tissues outside the living organism were carried out in glass containers, such as beakers, test tubes, or Petri dishes. Today, the scientific term "in vitro" is used to refer to any biological procedure that is performed outside the organism in which it would normally have occurred, to distinguish it from an in vivo procedure (such as in vivo fertilisation), where the tissue remains inside the living organism in which it is normally found.
A colloquial term for babies conceived as the result of IVF, "test tube babies", refers to the tube-shaped containers of glass or plastic resin, called test tubes, that are commonly used in chemistry and biology labs. However, IVF is usually performed in Petri dishes, which are both wider and shallower and often used to cultivate cultures.
IVF is a form of assisted reproductive technology. | 0 | Cryobiology |
Tungsten plays a large and indispensable role in modern high-tech industry. Up to 500,000 tons of raw tungsten ore are mined each year by Wolfram Bergbau und Hütten AG (WHB)in Felbertal, Austria, which is the largest scheelite deposit in Europe. 25% of the run-of-mine ore are separated as waste before entering the mill. | 1 | Separation Processes |
"Ultraviolet" means "beyond violet" (from Latin ultra, "beyond"), violet being the color of the highest frequencies of visible light. Ultraviolet has a higher frequency (thus a shorter wavelength) than violet light.
UV radiation was discovered in 1801 when the German physicist Johann Wilhelm Ritter observed that invisible rays just beyond the violet end of the visible spectrum darkened silver chloride-soaked paper more quickly than violet light itself. He called them "(de-)oxidizing rays" () to emphasize chemical reactivity and to distinguish them from "heat rays", discovered the previous year at the other end of the visible spectrum. The simpler term "chemical rays" was adopted soon afterwards, and remained popular throughout the 19th century, although some said that this radiation was entirely different from light (notably John William Draper, who named them "tithonic rays"). The terms "chemical rays" and "heat rays" were eventually dropped in favor of ultraviolet and infrared radiation, respectively. In 1878, the sterilizing effect of short-wavelength light by killing bacteria was discovered. By 1903, the most effective wavelengths were known to be around 250 nm. In 1960, the effect of ultraviolet radiation on DNA was established.
The discovery of the ultraviolet radiation with wavelengths below 200 nm, named "vacuum ultraviolet" because it is strongly absorbed by the oxygen in air, was made in 1893 by German physicist Victor Schumann. | 4 | Ultraviolet Radiation |