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A record-long of human transplant organ preservation with machine perfusion of a liver for 3 days rather than usually <12 hours was reported in 2022. It could possibly be extended to 10 days and prevent substantial cell damage by low temperature preservation methods. Alternative approaches include novel cryoprotectant solvents.
There is a novel organ perfusion system under development that can restore, i.e. on the cellular level, multiple vital (pig) organs one hour after death (during which the body had a prolonged warm ischaemia), and a similar method/system for reviving (pig) brains hours after death. The system for cellular recovery could be used to preserve donor organs or for revival-treatments in medical emergencies. | 1 | Cryobiology |
In solid state physics, the magnetic space groups, or Shubnikov groups, are the symmetry groups which classify the symmetries of a crystal both in space, and in a two-valued property such as electron spin. To represent such a property, each lattice point is colored black or white, and in addition to the usual three-dimensional symmetry operations, there is a so-called "antisymmetry" operation which turns all black lattice points white and all white lattice points black. Thus, the magnetic space groups serve as an extension to the crystallographic space groups which describe spatial symmetry alone.
The application of magnetic space groups to crystal structures is motivated by Curies Principle. Compatibility with a materials symmetries, as described by the magnetic space group, is a necessary condition for a variety of material properties, including ferromagnetism, ferroelectricity, topological insulation. | 7 | Magnetic Ordering |
Materials used in the construction of an in vivo bioreactor space vary widely depending on the type of substrate, type of tissue, and mechanical demands of said tissue being grown. At its simplest, a bioreactor space will be created between tissue layers through the use of hydrogel injections to create a bioreactor space. Early models used an impermeable silicone shroud to encase a scaffold, though more recent studies have begun 3D printing custom bioreactor molds to further enhance the mechanical growth properties of the bioreactors. The choice of bioreactor chamber material generally requires that it is nontoxic and medical grade, examples include: "silicon, polycarbonate, and acrylic polymer". Recently both Teflon and titanium have been used in the growth of bone. One study utilized Polymethyl methacrylate as a chamber material and 3D printed hollow rectangular blocks. Yet another study pushed the limits of the in vivo bioreactor by proving that the omentum is suitable as a bioreactor space and chamber. Specifically, highly vascularized and functional bladder tissue was grown within the omentum space. | 2 | Tissue Engineering |
1) The elastic modulus of the implant is decreased, allowing the implant to better match the elastic modulus of the bone. The elastic modulus of cortical bone (~18 GPa) is significantly lower than typical solid titanium or steel implants (110 GPa and 210 GPa, respectively), causing the implant take up a disproportionate amount of the load applied to the appendage, leading to an effect called stress shielding.
2) Porosity enables osteoblastic cells to grow into the pores of implants. Cells can span gaps of smaller than 75 microns and grow into pores larger than 200 microns. Bone ingrowth is a favorable effect, as it anchors the cells into the implant, increasing the strength of the bone-implant interface. More load is transferred from the implant to the bone, reducing stress shielding effects. The density of the bone around the implant is likely to be higher due to the increased load applied to the bone. Bone ingrowth reduces the likelihood of the implant loosening over time because stress shielding and corresponding bone resorption over extended timescales is avoided. Porosity of greater than 40% is favorable to facilitate sufficient anchoring of the osteoblastic cells. | 2 | Tissue Engineering |
The relationship between matric water potential and water content is the basis of the water retention curve. Matric potential measurements (Ψ) are converted to volumetric water content (θ) measurements based on a site or soil specific calibration curve. Hysteresis is a source of water content measurement error. Matric potential hysteresis arises from differences in wetting behaviour causing dry medium to re-wet; that is, it depends on the saturation history of the porous medium. Hysteretic behaviour means that, for example, at a matric potential (Ψ) of , the volumetric water content (θ) of a fine sandy soil matrix could be anything between 8% and 25%.
Tensiometers are directly influenced by this type of hysteresis. Two other types of sensors used to measure soil water matric potential are also influenced by hysteresis effects within the sensor itself. Resistance blocks, both nylon and gypsum based, measure matric potential as a function of electrical resistance. The relation between the sensor's electrical resistance and sensor matric potential is hysteretic. Thermocouples measure matric potential as a function of heat dissipation. Hysteresis occurs because measured heat dissipation depends on sensor water content, and the sensor water content–matric potential relationship is hysteretic. , only desorption curves are usually measured during calibration of soil moisture sensors. Despite the fact that it can be a source of significant error, the sensor specific effect of hysteresis is generally ignored. | 7 | Magnetic Ordering |
Even with current technologies, hECT structure and function is more at the level of newborn heart muscle than adult myocardium. Nonetheless, important advances have led to the generation of hECT patches for myocardial repair in animal models and use for in vitro models of drug screening. hECTs can also be used to experimentally model CVD using genetic manipulation and adenoviral-mediated gene transfer. In animal models of myocardial infarction (MI), hECT injection into the hearts of rats and mice reduces infarct size and improves heart function and contractility. As a proof of principle, grafts of engineered heart tissues have been implanted in rats following MI with beneficial effects on left ventricular function. The use of hECTs in generating tissue engineered heart valves is also being explored to improve current heart valve constructs for in vivo animal studies. As tissue engineering technology advances to overcome current limitations, hECTs are a promising avenue for experimental drug discovery, screening and disease modelling and in vivo repair. | 2 | Tissue Engineering |
Laser fusion progress: in 1983, the NOVETTE laser was completed. The following December, the ten-beam NOVA laser was finished. Five years later, NOVA produced 120 kilojoules of infrared light during a nanosecond pulse.
Research focused on either fast delivery or beam smoothness. Both focused on increasing energy uniformity. One early problem was that the light in the infrared wavelength lost energy before hitting the fuel. Breakthroughs were made at LLE at University of Rochester. Rochester scientists used frequency-tripling crystals to transform infrared laser beams into ultraviolet beams. | 3 | Nuclear Fusion |
Unlike the widely used automotive antifreeze, ethylene glycol, AFPs do not lower freezing point in proportion to concentration. Rather, they work in a noncolligative manner. This phenomenon allows them to act as an antifreeze at concentrations 1/300th to 1/500th of those of other dissolved solutes. Their low concentration minimizes their effect on osmotic pressure. The unusual properties of AFPs are attributed to their selective affinity for specific crystalline ice forms and the resulting blockade of the ice-nucleation process. | 1 | Cryobiology |
Although sedimentation might occur in tanks of other shapes, removal of accumulated solids is easiest with conveyor belts in rectangular tanks or with scrapers rotating around the central axis of circular tanks. Settling basins and clarifiers should be designed based on the settling velocity (v) of the smallest particle to be theoretically 100% removed. The overflow rate is defined as:
:Overflow rate (v ) = Flow of water (Q (m/s)) /(Surface area of settling basin (A(m))
In many countries this value is named as surface loading in m/h per m. Overflow rate is often used for flow over an edge (for example a weir) in the unit m/h per m.
The unit of overflow rate is usually meters (or feet) per second, a velocity. Any particle with settling velocity (v) greater than the overflow rate will settle out, while other particles will settle in the ratio v/v.
There are recommendations on the overflow rates for each design that ideally take into account the change in particle size as the solids move through the operation:
* Quiescent zones: per second
* Full-flow basins: per second
* Off-line basins: per second
However, factors such as flow surges, wind shear, scour, and turbulence reduce the effectiveness of settling. To compensate for these less than ideal conditions, it is recommended doubling the area calculated by the previous equation.
It is also important to equalize flow distribution at each point across the cross-section of the basin. Poor inlet and outlet designs can produce extremely poor flow characteristics for sedimentation.
Settling basins and clarifiers can be designed as long rectangles (Figure 1.a), that are hydraulically more stable and easier to control for large volumes. Circular clarifiers (Fig. 1.b) work as a common thickener (without the usage of rakes), or as upflow tanks (Fig. 1.c).
Sedimentation efficiency does not depend on the tank depth. If the forward velocity is low enough so that the settled material does not re-suspend from the tank floor, the area is still the main parameter when designing a settling basin or clarifier, taking care that the depth is not too low. | 5 | Separation Processes |
Most of the solid blanket materials that surround the fusion chamber in conventional designs are replaced by a fluorine lithium beryllium (FLiBe) molten salt that can easily be circulated/replaced, reducing maintenance costs.
The liquid blanket provides neutron moderation and shielding, heat removal, and a tritium breeding ratio ≥ 1.1. The large temperature range over which FLiBe is liquid permits blanket operation at with single-phase fluid cooling and a Brayton cycle. | 3 | Nuclear Fusion |
A rare sugar is a sugar that occurs in limited quantities in nature. Rare sugars can be made using enzymes, choosing which enzymes to use if you know the substrate can be aided by the Izumoring-strategy.
Specific examples of rare sugars are:
* Allulose
* Allose
* Sorbose
* Tagatose | 6 | Carbohydrates |
One recent, successful business endeavor has been the introduction of AFPs into ice cream and yogurt products. This ingredient, labelled ice-structuring protein, has been approved by the Food and Drug Administration. The proteins are isolated from fish and replicated, on a larger scale, in genetically modified yeast.
There is concern from organizations opposed to genetically modified organisms (GMOs) who believe that antifreeze proteins may cause inflammation. Intake of AFPs in diet is likely substantial in most northerly and temperate regions already. Given the known historic consumption of AFPs, it is safe to conclude their functional properties do not impart any toxicologic or allergenic effects in humans.
As well, the transgenic process of ice structuring proteins production is widely used in society. Insulin and rennet are produced using this technology. The process does not impact the product; it merely makes production more efficient and prevents the death of fish that would otherwise be killed to extract the protein.
Currently, Unilever incorporates AFPs into some of its American products, including some Popsicle ice pops and a new line of Breyers Light Double Churned ice cream bars. In ice cream, AFPs allow the production of very creamy, dense, reduced fat ice cream with fewer additives. They control ice crystal growth brought on by thawing on the loading dock or kitchen table, which reduces texture quality.
In November 2009, the Proceedings of the National Academy of Sciences published the discovery of a molecule in an Alaskan beetle that behaves like AFPs, but is composed of saccharides and fatty acids.
A 2010 study demonstrated the stability of superheated water ice crystals in an AFP solution, showing that while the proteins can inhibit freezing, they can also inhibit melting.
In 2021, EPFL and Warwick scientists have found an artificial imitation of antifreeze proteins. | 1 | Cryobiology |
Geometrical frustration is an important feature in magnetism, where it stems from the relative arrangement of spins. A simple 2D example is shown in Figure 1. Three magnetic ions reside on the corners of a triangle with antiferromagnetic interactions between them; the energy is minimized when each spin is aligned opposite to neighbors. Once the first two spins align antiparallel, the third one is frustrated because its two possible orientations, up and down, give the same energy. The third spin cannot simultaneously minimize its interactions with both of the other two. Since this effect occurs for each spin, the ground state is sixfold degenerate. Only the two states where all spins are up or down have more energy.
Similarly in three dimensions, four spins arranged in a tetrahedron (Figure 2) may experience geometric frustration. If there is an antiferromagnetic interaction between spins, then it is not possible to arrange the spins so that all interactions between spins are antiparallel. There are six nearest-neighbor interactions, four of which are antiparallel and thus favourable, but two of which (between 1 and 2, and between 3 and 4) are unfavourable. It is impossible to have all interactions favourable, and the system is frustrated.
Geometrical frustration is also possible if the spins are arranged in a non-collinear way. If we consider a tetrahedron with a spin on each vertex pointing along the easy axis (that is, directly towards or away from the centre of the tetrahedron), then it is possible to arrange the four spins so that there is no net spin (Figure 3). This is exactly equivalent to having an antiferromagnetic interaction between each pair of spins, so in this case there is no geometrical frustration. With these axes, geometric frustration arises if there is a ferromagnetic interaction between neighbours, where energy is minimized by parallel spins. The best possible arrangement is shown in Figure 4, with two spins pointing towards the centre and two pointing away. The net magnetic moment points upwards, maximising ferromagnetic interactions in this direction, but left and right vectors cancel out (i.e. are antiferromagnetically aligned), as do forwards and backwards. There are three different equivalent arrangements with two spins out and two in, so the ground state is three-fold degenerate. | 7 | Magnetic Ordering |
One, two or three IVF treatments are government subsidised for people who are younger than 40 and have no children. The rules for how many treatments are subsidised, and the upper age limit for the people, vary between different county councils. Single people are treated, and embryo adoption is allowed. There are also private clinics that offer the treatment for a fee. | 1 | Cryobiology |
Book chapters are cited in short form above and long form below. All other sources are cited above only.
*Coups, Elliot J. and Phillips, L. Alison (2012). "Prevalence and Correlates of Indoor Tanning", in Carolyn J. Heckman, Sharon L. Manne (eds.), Shedding Light on Indoor Tanning. Dordrecht: Springer Science & Business Media, 5–32.
*Hay, Jennifer and Lipsky, Samara (2012), "International Perspectives on Indoor Tanning", in Heckman and Manne (eds)., 179–193.
*Hunt, Yvonne; Augustson, Erik; Rutten, Lila; Moser, Richard; and Yaroch, Amy (2012). "History and Culture of Tanning in the United States", in Heckman and Manne (eds.), 33–68.
*Lessin, Stuart R; Perlis, Clifford S.; Zook, and Matthew B. Zook (2012). "How Ultraviolet Radiation Tans Skin" in Heckman and Manne (eds.), 87–94.
*Lluria-Prevatt, Maria; Dickinson, Sally E.; and Alberts, David S. (2013). "Skin Cancer Prevention", in David Alberts, Lisa M. Hess (eds.). Fundamentals of Cancer Prevention. Heidelberg and Berlin: Springer Verlag, 321–376. | 8 | Ultraviolet Radiation |
Ultraviolet radiation is invisible to the human eye, but illuminating certain materials with UV radiation causes the emission of visible light, causing these substances to glow with various colors. This is called fluorescence, and has many practical uses. Black lights are required to observe fluorescence, since other types of ultraviolet lamps emit visible light which drowns out the dim fluorescent glow. | 8 | Ultraviolet Radiation |
The largest "classic" pinch device was the ZETA, which started operation in the UK in 1957. Its name is a take-off on small experimental fission reactors that often had "zero energy" in their name, such as ZEEP.
In early 1958, John Cockcroft announced that fusion had been achieved in the ZETA, an announcement that made headlines around the world. He dismissed US physicists' concerns. US experiments soon produced similar neutrons, although temperature measurements suggested these could not be from fusion. The ZETA neutrons were later demonstrated to be from different versions of the instability processes that had plagued earlier machines. Cockcroft was forced to retract his fusion claims, tainting the entire field for years. ZETA ended in 1968. | 3 | Nuclear Fusion |
* Electronic article surveillance – using magnetostriction to prevent shoplifting
* Magnetostrictive delay lines - an earlier form of computer memory
* Magnetostrictive loudspeakers and headphones | 7 | Magnetic Ordering |
Optically stimulated luminescence dating is a related measurement method which replaces heating with exposure to intense light. The sample material is illuminated with a very bright source of green or blue light (for quartz) or infrared light (for potassium feldspar). Ultraviolet light emitted by the sample is detected for measurement. | 0 | Luminescence |
Besides being used in timepieces by industry and hobbyists, Super-LumiNova is also marketed for application on:
* Instruments: scales, dials, markings, indicators, etc.
* Scales: engravings, silkscreen-printing
* Aviation instruments and markings
* Jewelry
* Safety- and emergency panels, signs, markings
* Aiming posts
* Various other parts | 0 | Luminescence |
Field-induced polymer electroluminescent (FIPEL) technology is a low power electroluminescent light source. Three layers of moldable light-emitting polymer blended with a small amount of carbon nanotubes glow when an alternating current is passed through them. The technology can produce white light similar to that of the Sun, or other tints if desired. It is also more efficient than compact fluorescent lamps in terms of the energy required to produce light. As cited from the Carroll Research Group at Wake Forest University, "To date our brightest device – without output couplers – exceeds 18,000 cd/m2." This confirms that FIPEL technology is a viable solution for area lighting.
FIPEL lights are different from LED lighting, in that there is no junction. Instead, the light emitting component is a layer of polymer containing an iridium compound which is doped with multi-wall carbon nanotubes. This planar light emitting structure is energized by an AC field from insulated electrodes. The lights can be shaped into many different forms, from mimicking conventional light bulbs to unusual forms such as 2-foot-by-4-foot flat sheets and straight or bent tubes. The technology was developed by a team headed by Dr. David Carroll of Wake Forest University in Winston-Salem, North Carolina. | 0 | Luminescence |
Galactomannan is a component of the cell wall of the mold Aspergillus and is released during growth. Detection of galactomannan in blood is used to diagnose invasive aspergillosis infections in humans. This is performed with monoclonal antibodies in a double-sandwich ELISA; this assay from Bio-Rad Laboratories was approved by the FDA in 2003 and is of moderate accuracy. The assay is most useful in patients who have had hemopoietic cell transplants (stem cell transplants). False positive Aspergillus Galactomannan test have been found in patients on intravenous treatment with some antibiotics or fluids containing gluconate or citric acid such as some transfusion platelets, parenteral nutrition or PlasmaLyte. | 6 | Carbohydrates |
At the temperatures and densities in stellar cores, the rates of fusion reactions are notoriously slow. For example, at solar core temperature (T ≈ 15 MK) and density (160 g/cm), the energy release rate is only 276 μW/cm—about a quarter of the volumetric rate at which a resting human body generates heat. Thus, reproduction of stellar core conditions in a lab for nuclear fusion power production is completely impractical. Because nuclear reaction rates depend on density as well as temperature and most fusion schemes operate at relatively low densities, those methods are strongly dependent on higher temperatures. The fusion rate as a function of temperature (exp(−E/kT)), leads to the need to achieve temperatures in terrestrial reactors 10–100 times higher than in stellar interiors: T ≈ . | 3 | Nuclear Fusion |
Reddi is the founder of the International Conference on Bone Morphogenetic Proteins (BMPs). He organized the first conference at the Johns Hopkins University School of Medicine in 1994. The conference is held every two years rotating between the United States and an international venue. | 2 | Tissue Engineering |
Another firm researching hair cloning was ARI (Aderans Research Institute), a Japanese company that operated in the US and was the greatest competitor of Intercytex in developing the therapy. The company worked on what they called the "Ji Gami" process, which involved the removal of a small strip of the scalp, which is broken down into individual follicular stem cells. After the extraction, these cells are cultured, multiplied, and injected back into the bald areas of the scalp. Scientists hoped that after implantation these cloned follicular cells would mature into full-grown hair.
During Phase II trials they found that the process was not suitable for multiplication but instead, it revitalized the follicles and successfully prevented future loss. The trials continued in 2012. Aderans decided to discontinue the funding of its hair multiplication research in July 2013. | 2 | Tissue Engineering |
The main advantages of excimer lamps over other sources of UV and VUV radiation are as follows:
* high average specific power of UV radiation (up to 1 Watt per cubic centimeter of active medium);
* high energy of an emitted photon (from 3.5 to 11.5 eV);
* quasimonochromatic radiation with the spectral full-width at half maximum from 2 to 15 nm;
* high power spectral density of UV radiation;
* choice of the wavelength of the spectral maximum of UV radiation for specific purposes (see table);
* availability of multi-wave UV radiation owing to simultaneous excitation of several kinds of working excimer molecules;
* absence of visible and IR radiation;
* instant achievement of the operating mode;
* low heating of radiating surface;
* absence of mercury. | 8 | Ultraviolet Radiation |
The first approach of bioprinting is called biomimicry. The main goal of this approach is to create fabricated structures that are identical to the natural structure that are found in the tissues and organs in the human body. Biomimicry requires duplication of the shape, framework, and the microenvironment of the organs and tissues. The application of biomimicry in bioprinting involves creating both identical cellular and extracellular parts of organs. For this approach to be successful, the tissues must be replicated on a micro scale. Therefore, it is necessary to understand the microenvironment, the nature of the biological forces in this microenvironment, the precise organization of functional and supporting cell types, solubility factors, and the composition of extracellular matrix. | 2 | Tissue Engineering |
The mechanism of the phenomenon of sonoluminescence is unknown. Hypotheses include: hotspot, bremsstrahlung radiation, collision-induced radiation and corona discharges, nonclassical light, proton tunneling, electrodynamic jets and fractoluminescent jets (now largely discredited due to contrary experimental evidence).
In 2002, M. Brenner, S. Hilgenfeldt, and D. Lohse published a 60-page review that contains a detailed explanation of the mechanism. An important factor is that the bubble contains mainly inert noble gas such as argon or xenon (air contains about 1% argon, and the amount dissolved in water is too great; for sonoluminescence to occur, the concentration must be reduced to 20–40% of its equilibrium value) and varying amounts of water vapor. Chemical reactions cause nitrogen and oxygen to be removed from the bubble after about one hundred expansion-collapse cycles. The bubble will then begin to emit light. The light emission of highly compressed noble gas is exploited technologically in the argon flash devices.
During bubble collapse, the inertia of the surrounding water causes high pressure and high temperature, reaching around 10,000 kelvins in the interior of the bubble, causing the ionization of a small fraction of the noble gas present. The amount ionized is small enough for the bubble to remain transparent, allowing volume emission; surface emission would produce more intense light of longer duration, dependent on wavelength, contradicting experimental results. Electrons from ionized atoms interact mainly with neutral atoms, causing thermal bremsstrahlung radiation. As the wave hits a low energy trough, the pressure drops, allowing electrons to recombine with atoms and light emission to cease due to this lack of free electrons. This makes for a 160-picosecond light pulse for argon (even a small drop in temperature causes a large drop in ionization, due to the large ionization energy relative to photon energy). This description is simplified from the literature above, which details various steps of differing duration from 15 microseconds (expansion) to 100 picoseconds (emission).
Computations based on the theory presented in the review produce radiation parameters (intensity and duration time versus wavelength) that match experimental results with errors no larger than expected due to some simplifications (e.g., assuming a uniform temperature in the entire bubble), so it seems the phenomenon of sonoluminescence is at least roughly explained, although some details of the process remain obscure.
Any discussion of sonoluminescence must include a detailed analysis of metastability. Sonoluminescence in this respect is what is physically termed a bounded phenomenon meaning that the sonoluminescence exists in a bounded region of parameter space for the bubble; a coupled magnetic field being one such parameter. The magnetic aspects of sonoluminescence are very well documented. | 0 | Luminescence |
Crystallization requires an initiation step. This can be spontaneous or can be done by adding a small amount of the pure compound (a seed crystal) to the saturated solution, or can be done by simply scratching the glass surface to create a seeding surface for crystal growth. It is thought that even dust particles can act as simple seeds. | 5 | Separation Processes |
The field of organ printing stemmed from research in the area of stereolithography, the basis for the practice of 3D printing that was invented in 1984. In this early era of 3D printing, it was not possible to create lasting objects because of the material used for the printing process was not durable. 3D printing was instead used as a way to model potential end products that would eventually be made from different materials under more traditional techniques. In the beginning of the 1990s, nanocomposites were developed that allowed 3D printed objects to be more durable, permitting 3D printed objects to be used for more than just models. It was around this time that those in the medical field began considering 3D printing as an avenue for generating artificial organs. By the late 1990s, medical researchers were searching for biocompatible materials that could be used in 3D printing.
The concept of bioprinting was first demonstrated in 1988. At this time, a researcher used a modified HP inkjet printer to deposit cells using cytoscribing technology. Progress continued in 1999 when the first artificial organ made using bioprinting was printed by a team of scientist leads by Dr. Anthony Atala at the Wake Forest Institute for Regenerative Medicine. The scientists at Wake Forest printed an artificial scaffold for a human bladder and then seeded the scaffold with cells from their patient. Using this method, they were able to grow a functioning organ and ten years after implantation the patient had no serious complications.
After the bladder at Wake Forest, strides were taken towards printing other organs. In 2002, a miniature, fully functional kidney was printed. In 2003, Dr. Thomas Boland from Clemson University patented the use of inkjet printing for cells. This process utilized a modified spotting system for the deposition of cells into organized 3D matrices placed on a substrate. This printer allowed for extensive research into bioprinting and suitable biomaterials. For instance, since these initial findings, the 3D printing of biological structures has been further developed to encompass the production of tissue and organ structures, as opposed to cell matrices. Additionally, more techniques for printing, such as extrusion bioprinting, have been researched and subsequently introduced as a means of production.
In 2004, the field of bioprinting was drastically changed by yet another new bioprinter. This new printer was able to use live human cells without having to build an artificial scaffold first. In 2009, Organovo used this novel technology to create the first commercially available bioprinter. Soon after, Organovo's bioprinter was used to develop a biodegradable blood vessel, the first of its kind, without a cell scaffold.
In the 2010s and beyond, further research has been put forth into producing other organs, such as the liver and heart valves, and tissues, such as a blood-borne network, via 3D printing. In 2019, scientists in Israel made a major breakthrough when they were able to print a rabbit-sized heart with a network of blood vessels that were capable of contracting like natural blood vessels. The printed heart had the correct anatomical structure and function compared to real hearts. This breakthrough represented a real possibility of printing fully functioning human organs. In fact, scientists at the Warsaw Foundation for Research and Development of Science in Poland have been working on creating a fully artificial pancreas using bioprinting technology. As of today, these scientists have been able to develop a functioning prototype. This is a growing field and much research is still being conducted. | 2 | Tissue Engineering |
An implant is a medical device manufactured to replace a missing biological structure, support a damaged biological structure, or enhance an existing biological structure. For example, an implant may be a rod, used to strengthen weak bones. Medical implants are human-made devices, in contrast to a transplant, which is a transplanted biomedical tissue. The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone, or apatite depending on what is the most functional. In 2018, for example, American Elements developed a nickel alloy powder for 3D printing robust, long-lasting, and biocompatible medical implants. In some cases implants contain electronics, e.g. artificial pacemaker and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents. | 2 | Tissue Engineering |
All chromatographic purifications and separations which are executed via solvent gradient batch chromatography can be performed using MCSGP. Typical examples are reversed phase purification of peptides, hydrophobic interaction chromatography for fatty acids or for example ion exchange chromatography of proteins or antibodies. The process can effectively enrich components, which have been fed in only small amounts. Continuous capturing of antibodies without affinity chromatography can be realized with the MCSGP-process. | 5 | Separation Processes |
Extracellular matrix materials are commercially available and are used in reconstructive surgery, treatment of chronic wounds, and some orthopedic surgeries; as of January 2017 clinical studies were under way to use them in heart surgery to try to repair damaged heart tissue.
The use of fish skin with its natural constituent of omega 3, has been developed by an Icelandic company Kereceis. Omega 3 is a natural anti-inflammatory, and the fish skin material acts as a scaffold for cell regeneration. In 2016 their product Omega3 Wound was approved by the FDA for the treatment of chronic wounds and burns. In 2021 the FDA gave approval for Omega3 Surgibind to be used in surgical applications including plastic surgery. | 2 | Tissue Engineering |
Prosperetti found a way to accurately determine the internal pressure of the bubble using the following equation.
where is the temperature, is the thermal conductivity of the gas, and is the radial distance. | 0 | Luminescence |
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 . | 5 | Separation Processes |
Plants under horticultural care in a constructed landscape, typically a botanic garden or arboreta. This technique is similar to a field gene bank in that plants are maintained in the ambient environment, but the collections are typically not as genetically diverse or extensive. These collections are susceptible to hybridization, artificial selection, genetic drift, and disease transmission. Species that cannot be conserved by other ex situ techniques are often included in cultivated collections. | 1 | Cryobiology |
Spin waves can propagate in magnetic media with magnetic ordering such as ferromagnets and antiferromagnets. The frequencies of the precession of the magnetisation depend on the material and its magnetic parameters, in general precession frequencies are in the microwave from 1–100 GHz, exchange resonances in particular materials can even see frequencies up to several THz. This higher precession frequency opens new possibilities for analogue and digital signal processing.
Spin waves themselves have group velocities on the order of a few km per second. The damping of spin waves in a magnetic material also causes the amplitude of the spin wave to decay with distance, meaning the distance freely propagating spin waves can travel is usually only several 10s of μm. The damping of the dynamical magnetisation is accounted for phenomenologically by the Gilbert damping constant in the Landau-Lifshitz-Gilbert equation (LLG equation), the energy loss mechanism itself is not completely understood, but is known to arise microscopically from magnon-magnon scattering, magnon-phonon scattering and losses due to eddy currents. The Landau-Lifshitz-Gilbert equation is the equation of motion for the magnetisation. All of the properties of the magnetic systems such as the applied bias field, the samples exchange, anisotropy and dipolar fields are described in terms of an effective magnetic field that enters the Landau–Lifshitz–Gilbert equation. The study of damping in magnetic systems is an ongoing modern research topic.
The LL equation was introduced in 1935 by Landau and Lifshitz to model the precessional motion of magnetization in a solid with an effective magnetic field and with damping. Later, Gilbert modified the damping term, which in the limit of small damping yields identical results. The LLG equation is,
The constant is the Gilbert phenomenological damping parameter and depends on the solid, and is the electron gyromagnetic ratio. Here
Research in magnetism, like the rest of modern science, is conducted with a symbiosis of theoretical and experimental approaches. Both approaches go hand-in-hand, experiments test the predictions of theory and theory provides explanations and predictions of new experiments. The theoretical side focuses on numerical modelling and simulations, so called micromagnetic modelling. Programs such as OOMMF or NMAG are micromagnetic solvers that numerically solve the LLG equation with appropriate boundary conditions. Prior to the start of the simulation, magnetic parameters of the sample and the initial groundstate magnetisation and bias field details are stated. | 7 | Magnetic Ordering |
Piezoluminescence is a form of luminescence created by pressure upon certain solids. This phenomenon is characterized by recombination processes involving electrons, holes and impurity ion centres. Some piezoelectric crystals give off a certain amount of piezoluminescence when under pressure. Irradiated salts, such as NaCl, KCl, KBr and polycrystalline chips of LiF (TLD-100), have been found to exhibit piezoluminescent properties. It has also been discovered that ferroelectric polymers exhibit piezoluminescence upon the application of stress.
In the folk-literature surrounding psychedelic production, DMT, 5-MeO-DMT, and LSD have been reported to exhibit piezoluminescence. As specifically noted in the book Acid Dreams, it is stated that Augustus Owsley Stanley III, one of the most prolific producers of LSD in the 1960s, observed piezoluminescence in the compound's purest form, which observation is confirmed by Alexander Shulgin: "A totally pure salt, when dry and when shaken in the dark, will emit small flashes of white light." | 0 | Luminescence |
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." | 8 | Ultraviolet Radiation |
* A fake acid attack between rivals for a husband appears in Cecil B. DeMilles film Why Change Your Wife?' (1920).
* In "The Adventure of the Illustrious Client" by Sir Arthur Conan Doyle, the villainous Baron Adelbert Gruner has oil of vitriol thrown in his face by a wronged former mistress, disfiguring him. She is prosecuted for this but given the minimum sentence due to extenuating circumstances.
* DC Comics supervillain Two-Face's origin stories feature half his face disfigured with acid.
* In the 2002 series of He-Man and the Masters of the Universe, Skeletor owes his namesake skeletal face to an acid attack.
*Saving Face – A 2012 documentary film by Sharmeen Obaid Chinoy and Daniel Junge that follows Pakistani/British plastic surgeon Dr. Mohammad Jawad to his native Pakistan to aid women who were victims of acid attacks, and examines the Pakistani parliament's exercise in banning the act of acid burning. The film won the 2012 Academy Award for best Documentary Short.
* In Emmerdale, one of the characters, Ross Barton, is a victim of an acid attack (as depicted in a 2018 episode). The actor who portrayed Ross Barton has said that it was his idea that the character should be a victim of an acid attack, as he wanted to create an awareness campaign about this problem.
*Surkh Chandni – A 2019 Pakistani television series directed by Shahid Shafaat that follows the story of a girl who survived an acid attack and the harshness of society she has to face there after.
*Dirty God – a 2019 English film starring Vicky Knight as an acid attack victim seeking justice and healing. Knight is a real burn victim, although from a domestic fire rather than an acid attack.
* Infinite Jest – a 1996 novel featuring a scene in which Joelle Van Dynes mother tries to throw acid in her husbands face after he confesses his love for their daughter, Joelle, but instead misses and hits her.
* Uyare – a 2019 Indian Malayalam-language film focuses on an aspiring pilot, who is a victim of an acid attack and how the situation changes around her.
* Chhapaak – a 2020 Indian Hindi-language film based on the life of Laxmi Agarwal, an acid attack survivor.
* In Bergen – a 2022 biopic about Turkish singer Bergen, the acid attack that left her blind in one eye is depicted.
* In Coronation Street in 2023, two characters, Daisy Midgeley and Ryan Connor are victims of an acid attack when Daisy’s stalker, Justin attacks her with acid. Ryan jumps in between Daisy and Justin and receives more severe burns to his face while Daisy only receives moderate burns on her body.
* In Top Boy in 2019, a minor character is depicted being wrestled to the ground and doused with a bottle of unknown acid on his face in a gang attack orchestrated by a main character, Jamie. The victim is then shown at the end of the season wearing an eyepatch with burns on his face. He was also seen in the following season, also with an eyepatch on his face, implying that the acid attack had permanently blinded the victim in one eye.
* In 2023 Indian television series Jyoti... Umeedon Se Sajee tells about the story of an hardworking and a aspired women named, Jyoti whose life turns upside down as she is being turned into an victim of acid attack. | 4 | Acids + Bases |
Solvent impregnated resins (SIRs) are commercially available (macro)porous resins impregnated with a solvent/an extractant. In this approach, a liquid extractant is contained within the pores of (adsorption) particles. Usually, the extractant is an organic liquid. Its purpose is to extract one or more dissolved components from a surrounding aqueous environment. The basic principle combines adsorption, chromatography and liquid-liquid extraction. | 5 | Separation Processes |
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: | 7 | Magnetic Ordering |
ZnS exists in two main crystalline forms. This dualism is an example of polymorphism. In each form, the coordination geometry at Zn and S is tetrahedral. The more stable cubic form is known also as zinc blende or sphalerite. The hexagonal form is known as the mineral wurtzite, although it also can be produced synthetically. The transition from the sphalerite form to the wurtzite form occurs at around 1020 °C. | 0 | Luminescence |
In October 2022, researchers from the Japan-based Yokohama National University successfully cloned fully-grown mouse hair follicles for the first time in history. It may take 5-10 years for this technology to be tested successfully in humans. | 2 | Tissue Engineering |
Criticism of cold fusion claims generally take one of two forms: either pointing out the theoretical implausibility that fusion reactions have occurred in electrolysis setups or criticizing the excess heat measurements as being spurious, erroneous, or due to poor methodology or controls. There are several reasons why known fusion reactions are an unlikely explanation for the excess heat and associated cold fusion claims. | 3 | Nuclear Fusion |
Organoids enable to study how cells interact together in an organ, their interaction with their environment, how diseases affect them and the effect of drugs. In vitro culture makes this system easy to manipulate and facilitates their monitoring. While organs are difficult to culture because their size limits the penetration of nutrients, the small size of organoids limits this problem. On the other hand, they do not exhibit all organ features and interactions with other organs are not recapitulated in vitro. While research on stem cells and regulation of stemness was the first field of application of intestinal organoids, they are now also used to study e.g. uptake of nutrients, drug transport and secretion of incretin hormones. This is of great relevance in the context of malabsorption diseases as well as metabolic diseases such as obesity, insulin resistance, and diabetes. | 2 | Tissue Engineering |
Another type of geometrical frustration arises from the propagation of a local order. A main question that a condensed matter physicist faces is to explain the stability of a solid.
It is sometimes possible to establish some local rules, of chemical nature, which lead to low energy configurations and therefore govern structural and chemical order. This is not generally the case and often the local order defined by local interactions cannot propagate freely, leading to geometric frustration. A common feature of all these systems is that, even with simple local rules, they present a large set of, often complex, structural realizations. Geometric frustration plays a role in fields of condensed matter, ranging from clusters and amorphous solids to complex fluids.
The general method of approach to resolve these complications follows two steps. First, the constraint of perfect space-filling is relaxed by allowing for space curvature. An ideal, unfrustrated, structure is defined in this curved space. Then, specific distortions are applied to this ideal template in order to embed it into three dimensional Euclidean space. The final structure is a mixture of ordered regions, where the local order is similar to that of the template, and defects arising from the embedding. Among the possible defects, disclinations play an important role. | 7 | Magnetic Ordering |
In plasma physics, a burning plasma is one in which most of the heating comes from fusion reactions involving thermal plasma ions. The Sun and similar stars are a burning plasma, and in 2020 the National Ignition Facility achieved burning plasma. A closely related concept is that of an ignited plasma, in which all of the heating comes from fusion reactions. | 3 | Nuclear Fusion |
Unlike magnetic spin ordering where the antiferromagnetism can be defined by flipping the magnetization axis of two neighbor sites from a ferromagnetic configuration, flipping of the magnetization axis of a multipole is usually meaningless. Taking a moment as an example, if one flips the z-axis by making a rotation toward the y-axis, it just changes nothing. Therefore, a suggested definition of antiferromagnetic multipolar ordering is to flip their phases by , i.e. . In this regard, the antiferromagnetic spin ordering is just a special case of this definition, i.e. flipping the phase of a dipole moment is equivalent to flipping its magnetization axis. As for high rank multipoles, e.g. , it actually becomes a rotation and for it is even not any kind of rotation. | 7 | Magnetic Ordering |
In chemistry, a luminophore (sometimes shortened to lumophore) is an atom or functional group in a chemical compound that is responsible for its luminescent properties. Luminophores can be either organic or inorganic.
Luminophores can be further classified as fluorophores or phosphors, depending on the nature of the excited state responsible for the emission of photons. However, some luminophores cannot be classified as being exclusively fluorophores or phosphors. Examples include transition-metal complexes such as tris(bipyridine)ruthenium(II) chloride, whose luminescence comes from an excited (nominally triplet) metal-to-ligand charge-transfer (MLCT) state, which is not a true triplet state in the strict sense of the definition; and colloidal quantum dots, whose emissive state does not have either a purely singlet or triplet spin.
Most luminophores consist of conjugated π systems or transition-metal complexes. There are also purely inorganic luminophores, such as zinc sulfide doped with rare-earth metal ions, rare-earth metal oxysulfides doped with other rare-earth metal ions, yttrium oxide doped with rare-earth metal ions, zinc orthosilicate doped with manganese ions, etc. Luminophores can be observed in action in fluorescent lights, television screens, computer monitor screens, organic light-emitting diodes and bioluminescence.
The correct, textbook terminology is luminophore, not lumophore, although the latter term has been frequently used in the chemical literature. | 0 | Luminescence |
An excimer lamp (or excilamp) is a source of ultraviolet light based on spontaneous emission of excimer (exciplex) molecules. | 8 | Ultraviolet Radiation |
Corona discharge on electrical apparatus can be detected by its ultraviolet emissions. Corona causes degradation of electrical insulation and emission of ozone and nitrogen oxide.
EPROMs (Erasable Programmable Read-Only Memory) are erased by exposure to UV radiation. These modules have a transparent (quartz) window on the top of the chip that allows the UV radiation in. | 8 | Ultraviolet Radiation |
Ultraviolet germicidal irradiation (UVGI) is a disinfection technique employing ultraviolet (UV) light, particularly UV-C (180-280 nm), to kill or inactivate microorganisms. UVGI primarily inactivates microbes by damaging their genetic material, thereby inhibiting their capacity to carry out vital functions.
The use of UVGI extends to an array of applications, encompassing food, surface, air, and water disinfection. UVGI devices can inactivate microorganisms including bacteria, viruses, fungi, molds, and other pathogens. Recent studies have substantiated the ability of UV-C light to inactivate SARS-CoV-2, the strain of coronavirus that causes COVID-19.
UV-C wavelengths demonstrate varied germicidal efficacy and effects on biological tissue. Many germicidal lamps like low-pressure mercury (LP-Hg) lamps, with peak emissions around 254 nm, contain UV wavelengths that can be hazardous to humans. As a result, UVGI systems have been primarily limited to applications where people are not directly exposed, including hospital surface disinfection, [https://www.cdc.gov/coronavirus/2019-ncov/community/ventilation/uvgi.html upper-room UVGI], and water treatment. More recently, the application of wavelengths between 200-235 nm, often referred to as far-UVC, has gained traction for surface and air disinfection. These wavelengths are regarded as much safer due to their significantly reduced penetration into human tissue.
Notably, UV-C light is virtually absent in sunlight reaching the Earth's surface due to the absorptive properties of the ozone layer within the atmosphere. | 8 | Ultraviolet Radiation |
Luminous paint (or luminescent paint) is paint that emits visible light through fluorescence, phosphorescence, or radioluminescence. | 0 | Luminescence |
The Catholic Church opposes all kinds of assisted reproductive technology and artificial contraception, on the grounds that they separate the procreative goal of marital sex from the goal of uniting married couples.
The Catholic Church permits the use of a small number of reproductive technologies and contraceptive methods such as natural family planning, which involves charting ovulation times, and allows other forms of reproductive technologies that allow conception to take place from normative sexual intercourse, such as a fertility lubricant. Pope Benedict XVI had publicly re-emphasised the Catholic Church's opposition to in vitro fertilisation, saying that it replaces love between a husband and wife.
The Catechism of the Catholic Church, in accordance with the Catholic understanding of natural law, teaches that reproduction has an "inseparable connection" to the sexual union of married couples. In addition, the church opposes IVF because it might result in the disposal of embryos; in Catholicism, an embryo is viewed as an individual with a soul that must be treated as a person. The Catholic Church maintains that it is not objectively evil to be infertile, and advocates adoption as an option for such couples who still wish to have children.
Hindus welcome IVF as a gift for those who are unable to bear children and have declared doctors related to IVF to be conducting punya as there are several characters who were claimed to be born without intercourse, mainly Kaurav and five Pandavas.
Regarding the response to IVF by Islam, a general consensus from the contemporary Sunni scholars concludes that IVF methods are immoral and prohibited. However, Gad El-Hak Ali Gad El-Hak's ART fatwa includes that:
*IVF of an egg from the wife with the sperm of her husband and the transfer of the fertilised egg back to the uterus of the wife is allowed, provided that the procedure is indicated for a medical reason and is carried out by an expert physician.
*Since marriage is a contract between the wife and husband during the span of their marriage, no third party should intrude into the marital functions of sex and procreation. This means that a third party donor is not acceptable, whether he or she is providing sperm, eggs, embryos, or a uterus. The use of a third party is tantamount to zina, or adultery.
Within the Orthodox Jewish community the concept is debated as there is little precedent in traditional Jewish legal textual sources. Regarding laws of sexuality, religious challenges include masturbation (which may be regarded as "seed wasting"), laws related to sexual activity and menstruation (niddah) and the specific laws regarding intercourse. An additional major issue is that of establishing paternity and lineage. For a baby conceived naturally, the fathers identity is determined by a legal presumption (chazakah) of legitimacy: rov biot achar habaal – a womans sexual relations are assumed to be with her husband. Regarding an IVF child, this assumption does not exist and as such Rabbi Eliezer Waldenberg (among others) requires an outside supervisor to positively identify the father. Reform Judaism has generally approved IVF. | 1 | Cryobiology |
An electrostatic separator is a device for separating particles by mass in a low energy charged beam.
An example is the electrostatic precipitator used in coal-fired power plants to treat exhaust gas, removing small particles that cause air pollution.
Electrostatic separation is a process that uses electrostatic charges to separate crushed particles of material. An industrial process used to separate large amounts of material particles, electrostatic separating is most often used in the process of sorting mineral ore. This process can help remove valuable material from ore, or it can help remove foreign material to purify a substance. In mining, the process of crushing mining ore into particles for the purpose of separating minerals is called beneficiation.
Generally, electrostatic charges are used to attract or repel differently charged material. When electrostatic separation uses the force of attraction to sort particles, conducting particles stick to an oppositely charged object, such as a metal drum, thereby separating them from the particle mixture. When this type of beneficiation uses repelling force, it is normally employed to change the trajectory of falling objects to sort them into different places. This way, when a mixture of particles falls past a repelling object, the particles with the correct charge fall away from the other particles when they are repelled by the similarly charged object.
An electric charge can be positive or negative — objects with a positive charge repel other positively charged objects, thereby causing them to push away from each other, while a positively charged object would attract to a negatively charged object, thereby causing the two to draw together.
Experiments showing electrostatic sorting in action can help make the process more clear. To exhibit electrostatic separation at home, an experiment can be conducted using peanuts that are still in their shells. When the shells are rubbed off of the peanuts and gently smashed into pieces, an electrostatically charged device, like a comb rubbed quickly against a wool sweater, will pick up the peanut shells with static electricity. The lightweight crushed shells that are oppositely charged from the comb easily move away from the edible peanut parts when the comb is passed nearby.
The electrostatic separation of conductors is one method of beneficiation; another common beneficiation method is magnetic beneficiation. Electrostatic separation is a preferred sorting method when dealing with separating conductors from electrostatic separation non-conductors. In a similar way to that in which electrostatic separation sorts particles with different electrostatic charges magnetic beneficiation sorts particles that respond to a magnetic field. Electrostatic beneficiation is effective for removing particulate matter, such as ash from mined coal, while magnetic separation functions well for removing the magnetic iron ore from deposits of clay in the earth. | 5 | Separation Processes |
Pretreatment is important when working nanofiltration membranes due to their spiral-wound design. The material is engineered to allow one-way flow. The design does not allow for backpulsing with water or air agitation to scour its surface and remove accumulated solids. Since material cannot be removed from the membrane surface, it is susceptible to fouling (loss of production capacity). Therefore, pretreatment is a necessity for any RO or nanofiltration system. Pretreatment has four major components:
* Screening solids: Solids must be removed and the water treated to prevent membrane fouling by particle or biological growth, and reduce the risk of damage to high-pressure components.
* Cartridge filtration: String-wound polypropylene filters are typically used to remove particles of 1–5 µm diameter.
* Dosing: Oxidizing biocides, such as chlorine, are added to kill bacteria, followed by bisulfite dosing to deactivate the chlorine that can destroy a thin-film composite membrane. Biofouling inhibitors do not kill bacteria, while preventing them from growing slime on the membrane surface and plant walls.
* Prefiltration pH adjustment: If the pH, hardness and the alkalinity in the feedwater result in scaling while concentrated in the reject stream, acid is dosed to maintain carbonates in their soluble carbonic acid form.
:CO + HO = HCO + HO
:HCO + HO = HCO + HO
* Carbonic acid cannot combine with calcium to form calcium carbonate scale. Calcium carbonate scaling tendency is estimated using the Langelier saturation index. Adding too much sulfuric acid to control carbonate scales may result in calcium sulfate, barium sulfate, or strontium sulfate scale formation on the membrane.
* Prefiltration antiscalants: Scale inhibitors (also known as antiscalants) prevent formation of more scales than acid, which can only prevent formation of calcium carbonate and calcium phosphate scales. In addition to inhibiting carbonate and phosphate scales, antiscalants inhibit sulfate and fluoride scales and disperse colloids and metal oxides. Despite claims that antiscalants can inhibit silica formation, no concrete evidence proves that silica polymerization is inhibited by antiscalants. Antiscalants can control acid-soluble scales at a fraction of the dosage required to control the same scale using sulfuric acid.
* Some small-scale desalination units use beach wells. These are usually drilled on the seashore. These intake facilities are relatively simple to build and the seawater they collect is pretreated via slow filtration through subsurface sand/seabed formations. Raw seawater collected using beach wells is often of better quality in terms of solids, silt, oil, grease, organic contamination, and microorganisms, compared to open seawater intakes. Beach intakes may also yield source water of lower salinity. | 5 | Separation Processes |
3D printing for the manufacturing of artificial organs has been a major topic of study in biological engineering. As the rapid manufacturing techniques entailed by 3D printing become increasingly efficient, their applicability in artificial organ synthesis has grown more evident. Some of the primary benefits of 3D printing lie in its capability of mass-producing scaffold structures, as well as the high degree of anatomical precision in scaffold products. This allows for the creation of constructs that more effectively resemble the microstructure of a natural organ or tissue structure. Organ printing using 3D printing can be conducted using a variety of techniques, each of which confers specific advantages that can be suited to particular types of organ production. | 2 | Tissue Engineering |
Anisotropic energy is energy that is directionally specific. The word anisotropy means "directionally dependent", hence the definition. The most common form of anisotropic energy is magnetocrystalline anisotropy, which is commonly studied in ferromagnets. In ferromagnets, there are islands or domains of atoms that are all coordinated in a certain direction; this spontaneous positioning is often called the "easy" direction, indicating that this is the lowest energy state for these atoms. In order to study magnetocrystalline anisotropy, energy (usually in the form of an electric current) is applied to the domain, which causes the crystals to deflect from the "easy" to "hard" positions. The energy required to do this is defined as the anisotropic energy. The easy and hard alignments and their relative energies are due to the interaction between spin magnetic moment of each atom and the crystal lattice of the compound being studied. | 7 | Magnetic Ordering |
Lithium burning is a nucleosynthetic process in which lithium is depleted in a star. Lithium is generally present in brown dwarfs and not in older low-mass stars. Stars, which by definition must achieve the high temperature (2.5 × 10 K) necessary for fusing hydrogen, rapidly deplete their lithium. | 3 | Nuclear Fusion |
Sensor-based ore sorting is financially especially attractive for low grade or marginal ore or waste dump material. This described scenario describes that waste dump material or marginal ore is sorted and added to the run-of-mine production. The needed capacity for the sensor-based ore sorting step is less in this case such as the costs involved. Requirement is that two crude material streams are fed in parallel, requiring two crushing stations. Alternatively, marginal and high grade ore can be buffered on an intermediate stockpile and dispatched in an alternating operation. The latter option has the disadvantage that the planned production time, the loading, of the sensor-based ore sorter is low, unless a significant intermediate stockpile or bunker is installed. Treating the marginal ore separately has the advantage that less equipment is needed since the processed material stream is lower, but it has the disadvantage that the potential of the technology is not unfolded for the higher grade material, where sensor-based sorting would also add benefit. | 5 | Separation Processes |
Bioprinting can also be used for cultured meat. In 2021, a steak-like cultured meat, composed of three types of bovine cell fibers was produced. The Wagyu-like beef has a structure similar to original meat. This technology provides an alternative to natural meat harvesting methods if the livestock industry is plagued by disease. In addition, it provides a possible solution to reducing the environmental impact of the livestock industry. | 2 | Tissue Engineering |
Under normal physiological conditions, inflammatory cells protect the body from foreign objects, and the body undergoes a foreign body reaction based on the adsorption of blood and proteins on the biomaterial surface. In the first two to four weeks post implant, there is an association between biomaterial adherent macrophages and cytokine expression near the foreign implant site, which can be explored using semi-quantitative RT-PCR. Macrophages fuse together to form foreign body giant cells (FBGCs), which similarly express cytokine receptors on their cell membranes and actively participate in the inflammatory response. Device failure in organic polyether polyurethane (PEU) pacemakers compared to silicone rubber showcases that the foreign body response may indeed lead to degradation of biomaterials, causing subsequent device failures. The utilization of to prevent functionality and durability compromise is proposed to minimize and slow the rate of biomaterial degradation. | 2 | Tissue Engineering |
Cold fusion setups utilize an input power source (to ostensibly provide activation energy), a platinum group electrode, a deuterium or hydrogen source, a calorimeter, and, at times, detectors to look for byproducts such as helium or neutrons. Critics have variously taken issue with each of these aspects and have asserted that there has not yet been a consistent reproduction of claimed cold fusion results in either energy output or byproducts. Some cold fusion researchers who claim that they can consistently measure an excess heat effect have argued that the apparent lack of reproducibility might be attributable to a lack of quality control in the electrode metal or the amount of hydrogen or deuterium loaded in the system. Critics have further taken issue with what they describe as mistakes or errors of interpretation that cold fusion researchers have made in calorimetry analyses and energy budgets. | 3 | Nuclear Fusion |
Three dimensional (3D) bioprinting is the utilization of 3D printing–like techniques to combine cells, growth factors, bio-inks, and biomaterials to fabricate functional structures that were traditionally used for tissue engineering applications but in recent times have seen increased interest in other applications such as biosensing, and environmental remediation. Generally, 3D bioprinting utilizes a layer-by-layer method to deposit materials known as bio-inks to create tissue-like structures that are later used in various medical and tissue engineering fields. 3D bioprinting covers a broad range of bioprinting techniques and biomaterials. Currently, bioprinting can be used to print tissue and organ models to help research drugs and potential treatments. Nonetheless, translation of bioprinted living cellular constructs into clinical application is met with several issues due to the complexity and cell number necessary to create functional organs. However, innovations span from bioprinting of extracellular matrix to mixing cells with hydrogels deposited layer by layer to produce the desired tissue. In addition, 3D bioprinting has begun to incorporate the printing of scaffolds which can be used to regenerate joints and ligaments. Apart from these, 3D bioprinting has recently been used in environmental remediation applications, including the fabrication of functional biofilms that host functional microorganisms that can facilitate pollutant removal. | 2 | Tissue Engineering |
Ex situ conservation (literally "off-site conservation") is the process of protecting an endangered species, variety or breed, of plant or animal outside its natural habitat. For example, by removing part of the population from a threatened habitat and placing it in a new location, an artificial environment which is similar to the natural habitat of the respective animal and within the care of humans, such as a zoological park or wildlife sanctuary. The degree to which humans control or modify the natural dynamics of the managed population varies widely, and this may include alteration of living environments, reproductive patterns, access to resources, and protection from predation and mortality.
Ex situ management can occur within or outside a species natural geographic range. Individuals maintained ex situ exist outside an ecological niche. This means that they are not under the same selection pressures as wild populations, and they may undergo artificial selection if maintained ex situ' for multiple generations.
Agricultural biodiversity is also conserved in ex situ collections. This is primarily in the form of gene banks where samples are stored in order to conserve the genetic resources of major crop plants and their wild relatives. | 1 | Cryobiology |
Because nuclei are all positively charged, they strongly repel one another. Normally, in the absence of a catalyst such as a muon, very high kinetic energies are required to overcome this charged repulsion. Extrapolating from known fusion rates, the rate for uncatalyzed fusion at room-temperature energy would be 50 orders of magnitude lower than needed to account for the reported excess heat. In muon-catalyzed fusion there are more fusions because the presence of the muon causes deuterium nuclei to be 207 times closer than in ordinary deuterium gas. But deuterium nuclei inside a palladium lattice are further apart than in deuterium gas, and there should be fewer fusion reactions, not more.
Paneth and Peters in the 1920s already knew that palladium can absorb up to 900 times its own volume of hydrogen gas, storing it at several thousands of times the atmospheric pressure. This led them to believe that they could increase the nuclear fusion rate by simply loading palladium rods with hydrogen gas. Tandberg then tried the same experiment but used electrolysis to make palladium absorb more deuterium and force the deuterium further together inside the rods, thus anticipating the main elements of Fleischmann and Pons' experiment. They all hoped that pairs of hydrogen nuclei would fuse together to form helium, which at the time was needed in Germany to fill zeppelins, but no evidence of helium or of increased fusion rate was ever found.
This was also the belief of geologist Palmer, who convinced Steven Jones that the helium-3 occurring naturally in Earth perhaps came from fusion involving hydrogen isotopes inside catalysts like nickel and palladium. This led their team in 1986 to independently make the same experimental setup as Fleischmann and Pons (a palladium cathode submerged in heavy water, absorbing deuterium via electrolysis). Fleischmann and Pons had much the same belief, but they calculated the pressure to be of 10 atmospheres, when cold fusion experiments achieve a loading ratio of only one to one, which has only between 10,000 and 20,000 atmospheres. John R. Huizenga says they had misinterpreted the Nernst equation, leading them to believe that there was enough pressure to bring deuterons so close to each other that there would be spontaneous fusions. | 3 | Nuclear Fusion |
The lack of two important enzymes in fructose metabolism results in the development of two inborn errors in carbohydrate metabolism – essential fructosuria and hereditary fructose intolerance. In addition, reduced phosphorylation potential within hepatocytes can occur with intravenous infusion of fructose. | 6 | Carbohydrates |
A fluorophore (or fluorochrome, similarly to a chromophore) is a fluorescent chemical compound that can re-emit light upon light excitation. Fluorophores typically contain several combined aromatic groups, or planar or cyclic molecules with several π bonds.
Fluorophores are sometimes used alone, as a tracer in fluids, as a dye for staining of certain structures, as a substrate of enzymes, or as a probe or indicator (when its fluorescence is affected by environmental aspects such as polarity or ions). More generally they are covalently bonded to macromolecules, serving as a markers (or dyes, or tags, or reporters) for affine or bioactive reagents (antibodies, peptides, nucleic acids). Fluorophores are notably used to stain tissues, cells, or materials in a variety of analytical methods, such as fluorescent imaging and spectroscopy.
Fluorescein, via its amine-reactive isothiocyanate derivative fluorescein isothiocyanate (FITC), has been one of the most popular fluorophores. From antibody labeling, the applications have spread to nucleic acids thanks to carboxyfluorescein. Other historically common fluorophores are derivatives of rhodamine (TRITC), coumarin, and cyanine. Newer generations of fluorophores, many of which are proprietary, often perform better, being more photostable, brighter, or less pH-sensitive than traditional dyes with comparable excitation and emission. | 0 | Luminescence |
Filtrate is the waste that has been discharge in vacuum ceramic filters through the waste stream. During cake washing, a wash liquid is sprayed on the cake solids to remove impurities or additional filtrate. The filtrate goes into filtrate tank and is drained through a discharge system. However, the filtrate is recyclable and has low suspended solid content. Thus, it can be recycled through the system without further treatment. Filtrate is used to flush the disc during back flow washing to clean the micro-porous structure and remove any residual cake. | 5 | Separation Processes |
The surrounding blanket can be a fissile material (enriched uranium or plutonium) or a fertile material (capable of conversion to a fissionable material by neutron bombardment) such as thorium, depleted uranium or spent nuclear fuel. Such subcritical reactors (which also include particle accelerator-driven neutron spallation systems) offer the only currently-known means of active disposal (versus storage) of spent nuclear fuel without reprocessing. Fission by-products produced by the operation of commercial light water nuclear reactors (LWRs) are long-lived and highly radioactive, but they can be consumed using the excess neutrons in the fusion reaction along with the fissionable components in the blanket, essentially destroying them by nuclear transmutation and producing a waste product which is far safer and less of a risk for nuclear proliferation. The waste would contain significantly reduced concentrations of long-lived, weapons-usable actinides per gigawatt-year of electric energy produced compared to the waste from a LWR. In addition, there would be about 20 times less waste per unit of electricity produced. This offers the potential to efficiently use the very large stockpiles of enriched fissile materials, depleted uranium, and spent nuclear fuel. | 3 | Nuclear Fusion |
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). | 6 | Carbohydrates |
The preferred method to remove all cellular components from a heart is perfusion decellularization. This technique involves perfusing the heart with detergents such as SDS and Triton X-100 dissolved in distilled water.
The remaining ECM is composed of structural elements such as collagen, laminin, elastin and fibronectin. The ECM scaffold promotes proper cellular proliferation and differentiation, vascular development, as well as providing mechanical support for cellular growth. Because minimal DNA material remains after the decellularization process, the engineered organ is biocompatible with the transplant recipient, regardless of species. Unlike traditional transplant options, recellularized hearts are less immunogenic and have a decreased risk of rejection.
Once the decellularized heart has been sterilized to remove any pathogens, the recellularization process can occur. Multipotent cardiovascular progenitors are then added to the decellularized heart and with additional exogenous growth factors, are stimulated to differentiate into cardiomyocytes, smooth muscle cells and endothelial cells. | 2 | Tissue Engineering |
The first successful transplantation of an organoid into a human, a patient with ulcerative colitis whose cells were used for the organoid, was carried out in 2022. | 2 | Tissue Engineering |
As hypothermia progresses, symptoms include: mental status changes such as amnesia, confusion, slurred speech, decreased reflexes, and loss of fine motor skills. | 1 | Cryobiology |
In 2012 scientists from the University of Pennsylvania School of Medicine published their own findings regarding hair cloning. During their investigation, they found that non-bald and bald scalps have the same number of stem cells, but the progenitor cell number was significantly depleted in the case of the latter. Based on this, they concluded that it is not the absence of the stem cells that are responsible for hair loss but the unsuccessful activation of said cells.
The researchers continued their investigation and are looking for a way to convert regular stem cells into progenitor cells, which could mean they may be able to activate the natural generation of hair on a previously bald scalp. | 2 | Tissue Engineering |
Human skin is the first line of defense against many pathogens and can itself be subject to a variety of diseases and issues, such as cancers and inflammation. As such, skin-on-a-chip (SoC) applications include testing of topical pharmaceuticals and cosmetics, studying the pathology of skin diseases and inflammation, and "creating noninvasive automated cellular assays" to test for the presence of antigens or antibodies that could denote the presence of a pathogen. Despite the wide variety of potential applications, relatively little research has gone into developing a skin-on-a-chip compared to many other organ-on-a-chips, such as lungs and kidneys. Issues such as detachment of the collagen scaffolding from microchannels, incomplete cellular differentiation, and predominant use of poly(dimethysiloxane) (PDMS) for device fabrication, which has been shown to leach chemicals into biological samples and cannot be mass-produced stymie standardization of a platform. One additional difficulty is the variability of cell-culture scaffolding, or the base substance in which to culture cells, that is used in skin-on-chip devices. In the human body, this substance is known as the extracellular matrix.
The extracellular matrix (ECM) is composed primarily of collagen, and various collagen-based scaffolding has been tested in SoC models. Collagen tends to detach from the microfluidic backbone during culturing due to the contraction of fibroblasts. One study attempted to address this problem by comparing the qualities of collagen scaffolding from three different animal sources: pig skin, rat tail, and duck feet. Other studies also faced detachment issues due to contraction, which can problematic considering that the process of full skin differentiation can take up to several weeks. Contraction issues have been avoided by replacing collagen scaffolding with a fibrin-based dermal matrix, which did not contract. Greater differentiation and formation of cell layers was also reported in microfluidic culture when compared to traditional static culture, agreeing with earlier findings of improved cell-cell and cell-matrix interactions due to dynamic perfusion, or increased permeation through interstitial spaces due to the pressure from continuous media flow. This improved differentiation and growth is thought to be in part a product of shear stress created by the pressure gradient along a microchannel due to fluid flow, which may also improve nutrient supply to cells not directly adjacent to the medium. In static cultures, used in traditional skin equivalents, cells receive nutrients in the medium only through diffusion, whereas dynamic perfusion can improve nutrient flow through interstitial spaces, or gaps between cells. This perfusion has also been demonstrated to improve tight junction formation of the stratum corneum, the tough outer layer of the epidermis, which is the main barrier to penetration of the surface layer of the skin.
Dynamic perfusion may also improve cell viability, demonstrated by placing a commercial skin equivalent in a microfluidic platform that extended the expected lifespan by several weeks. This early study also demonstrated the importance of hair follicles in skin equivalent models. Hair follicles are the primary route into the subcutaneous layer for topical creams and other substances applied to the surface of the skin, a feature that more recent studies have often not accounted for.
One study developed a SoC consisting of three layers, the epidermis, dermis, and endothelial layer, separated by porous membranes, to study edema, swelling due to extracellular fluid accumulation, a common response to infection or injury and an essential step for cellular repair. It was demonstrated that pre-application of Dex, a steroidal cream with anti-inflammatory properties, reduced this swelling in the SoC. | 2 | Tissue Engineering |
The dilution in welding terms is defined as the weight of the base metal melted divided by the total weight of the weld metal. For example, if we have a dilution of 0.40, the fraction of the weld metal that came from the consumable electrode is 0.60. | 5 | Separation Processes |
Hysteresis is the dependence of the state of a system on its history. For example, a magnet may have more than one possible magnetic moment in a given magnetic field, depending on how the field changed in the past. Plots of a single component of the moment often form a loop or hysteresis curve, where there are different values of one variable depending on the direction of change of another variable. This history dependence is the basis of memory in a hard disk drive and the remanence that retains a record of the Earth's magnetic field magnitude in the past. Hysteresis occurs in ferromagnetic and ferroelectric materials, as well as in the deformation of rubber bands and shape-memory alloys and many other natural phenomena. In natural systems, it is often associated with irreversible thermodynamic change such as phase transitions and with internal friction; and dissipation is a common side effect.
Hysteresis can be found in physics, chemistry, engineering, biology, and economics. It is incorporated in many artificial systems: for example, in thermostats and Schmitt triggers, it prevents unwanted frequent switching.
Hysteresis can be a dynamic lag between an input and an output that disappears if the input is varied more slowly; this is known as rate-dependent hysteresis. However, phenomena such as the magnetic hysteresis loops are mainly rate-independent, which makes a durable memory possible.
Systems with hysteresis are nonlinear, and can be mathematically challenging to model. Some hysteretic models, such as the Preisach model (originally applied to ferromagnetism) and the Bouc–Wen model, attempt to capture general features of hysteresis; and there are also phenomenological models for particular phenomena such as the Jiles–Atherton model for ferromagnetism.
It is difficult to define hysteresis precisely. Isaak D. Mayergoyz wrote "...the very meaning of hysteresis varies from one area to another, from paper to paper and from author to author. As a result, a stringent mathematical definition of hysteresis is needed in order to avoid confusion and ambiguity.". | 7 | Magnetic Ordering |
The basis of many functional gastrointestinal disorders (FGIDs) is distension of the intestinal lumen. Such luminal distension may induce pain, a sensation of bloating, abdominal distension and motility disorders. Therapeutic approaches seek to reduce factors that lead to distension, particularly of the distal small and proximal large intestine. Food substances that can induce distension are those that are poorly absorbed in the proximal small intestine, osmotically active, and fermented by intestinal bacteria with hydrogen (as opposed to methane) production. The small molecule FODMAPs exhibit these characteristics.
Over many years, there have been multiple observations that ingestion of certain short-chain carbohydrates, including lactose, fructose and sorbitol, fructans and galactooligosaccharides, can induce gastrointestinal discomfort similar to that of people with irritable bowel syndrome. These studies also showed that dietary restriction of short-chain carbohydrates was associated with symptoms improvement.
These short-chain carbohydrates (lactose, fructose and sorbitol, fructans and GOS) behave similarly in the intestine. Firstly, being small molecules and either poorly absorbed or not absorbed at all, they drag water into the intestine via osmosis. Secondly, these molecules are readily fermented by colonic bacteria, so upon malabsorption in the small intestine they enter the large intestine where they generate gases (hydrogen, carbon dioxide and methane). The dual actions of these carbohydrates cause an expansion in volume of intestinal contents, which stretches the intestinal wall and stimulates nerves in the gut. It is this stretching that triggers the sensations of pain and discomfort that are commonly experienced by people with IBS.
The FODMAP concept was first published in 2005 as part of a hypothesis paper. In this paper, it was proposed that a collective reduction in the dietary intake of all indigestible or slowly absorbed, short-chain carbohydrates would minimise stretching of the intestinal wall. This was proposed to reduce stimulation of the guts nervous system and provide the best chance of reducing symptom generation in people with IBS (see below). At the time, there was no collective term for indigestible or slowly absorbed, short-chain carbohydrates, so the term FODMAP' was created to improve understanding and facilitate communication of the concept.
The low FODMAP diet was originally developed by a research team at Monash University in Melbourne, Australia. The Monash team undertook the first research to investigate whether a low FODMAP diet improved symptom control in patients with IBS and established the mechanism by which the diet exerted its effect. Monash University also established a rigorous food analysis program to measure the FODMAP content of a wide selection of Australian and international foods. The FODMAP composition data generated by Monash University updated previous data that was based on limited literature, with guesses (sometimes wrong) made where there was little information. | 6 | Carbohydrates |
All current Tengion's regenerative medicine product candidates are investigational and will not be commercially available until the completion of clinical trials and the review and approval of associated marketing applications by the Food and Drug Administration. | 2 | Tissue Engineering |
Most commonly used post treatment, where chlorine is dissolved in water to form and hydrochloric acid hypochlorous acid. The latter act as a disinfectant that is able to eliminate pathogens such as bacteria, viruses and protozoa by penetrating the cell walls. | 5 | Separation Processes |
Cryosurgery is a minimally invasive procedure, and is often preferred to other types of surgery because of its safety, ease of use, minimal pain and scarring as well as low cost; however, as with any medical treatment, there are risks involved, primarily that of damage to nearby healthy tissue. Damage to nerve tissue is of particular concern but is rare.
Cryosurgery cannot be used on lesions that would subsequently require biopsy as the technique destroys tissue and precludes the use of histopathology.
More common complications of cryosurgery include blistering and edema which are transient. Cryosurgery may cause complications due to damage of underlying structures. Destruction of the basement membrane may cause scarring and destruction of hair follicles can cause alopecia or hair loss. Occasionally, hypopigmentation may occur in the area of skin treated with cryosurgery, however, this complication is usually transient and often resolves as melanocytes migrate and repigment the area over several months. Bleeding can also occur, which can be delayed or immediate, due to damage of underlying arteries and arterioles. Tendon rupture and cartillage necrosis can occur, particularly if cryosurgery is done over bony prominences. These complications can be avoided or minimized if freeze times of less than 30 seconds are used during cryosurgery.
Patients undergoing cryosurgery usually experience redness and minor-to-moderate localized pain, which most of the time can be alleviated sufficiently by oral administration of mild analgesics such as ibuprofen, codeine or acetaminophen (paracetamol). Blisters may form as a result of cryosurgery, but these usually scab over and peel away within a few days. | 1 | Cryobiology |
*[http://www.users.globalnet.co.uk/~qtls/ GlobalNet.co.uk], Quaternary TL Surveys - Guide to thermoluminescence date measurement
*Aitken, M.J., Thermoluminescence Dating, Academic Press, London (1985) – Standard text for introduction to the field. Quite complete and rather technical, but well written and well organized. There is a second edition.
*Aitken, M.J., Introduction to Optical Dating, Oxford University Press (1998) – Good introduction to the field.
*Keizars, K.Z. 2003. NRTL as a method of analysis of sand transport along the coast of the St. Joseph Peninsula, Florida. GAC/MAC 2003. Presentation: Brock University, St. Catharines, Ontario, Canada.
* [http://www.jcronline.org/perlserv/?request=get-abstract&doi=10.2112%2F04-0406.1 JCRonline.org], Ķeizars, Z., Forrest, B., Rink, W.J. 2008. Natural Residual Thermoluminescence as a Method of Analysis of Sand Transport along the Coast of the St. Joseph Peninsula, Florida. Journal of Coastal Research, 24: 500–507.
*Keizars, Z. 2008b. NRTL trends observed in the sands of St. Joseph Peninsula, Florida. Queens University. Presentation: Queens University, Kingston, Ontario, Canada.
*Liritzis, I., 2011. Surface Dating by Luminescence: An Overview. Geochronometria, 38(3): 292–302.
*Mortlock, AJ; Price, D and Gardiner, G. The Discovery and Preliminary Thermoluminescence Dating of Two Aboriginal Cave Shelters in the Selwyn Ranges, Queensland [online]. Australian Archaeology, No. 9, Nov 1979: 82–86. Availability: <[https://archive.today/20150204113920/http://search.informit.com.au/documentSummary;dn=993492375664325;res=IELHSS]> . [cited 04 Feb 15].
* [http://www.antiquity.ac.uk/ant/079/ant0790390.htm Antiquity.ac.uk], Rink, W. J., Bartoll, J. 2005. Dating the geometric Nasca lines in the Peruvian desert. Antiquity, 79: 390–401.
*Sullasi, H. S., Andrade, M. B., Ayta, W. E. F., Frade, M., Sastry, M. D., & Watanabe, S. (2004). Irradiation for dating Brazilian fish fossil by thermoluminescence and EPR technique. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 213, 756–760.[http://doi:10.1016/S0168-583X(03)01698-7 doi:10.1016/S0168-583X(03)01698-7] | 0 | Luminescence |
The rapid development in the multidisciplinary field of tissue engineering has resulted in a variety of new and innovative medicinal products, often carrying living cells, intended to repair, regenerate or replace damaged human tissue. Tissue engineered medicinal products (TEMPs) vary in terms of the type and origin of cells and the product’s complexity. As all medicinal products, the safety and efficacy of TEMPs must be consistent throughout the manufacturing process. Quality control and assurance are of paramount importance and products are constantly assessed throughout the manufacturing process to ensure their safety, efficacy, consistency and reproducibility between batches. The European Medicines Agency (EMA) is responsible for the development, assessment and supervision of medicines in the EU. The appointed committees are involved in referral procedures concerning safety or the balance of benefit/risk of a medicinal product. In addition, the committees organize inspections with regards to the conditions under which medicinal products are being manufactured. For example, the compliance with good manufacturing practice (GMP), good clinical practice (GCP), good laboratory practice (GLP) and pharmacovigilance (PhV). | 2 | Tissue Engineering |
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. | 1 | Cryobiology |
The Penning source is a low gas pressure, cold cathode ion source which utilizes crossed electric and magnetic fields. The ion source anode is at a positive potential, either dc or pulsed, with respect to the source cathode. The ion source voltage is normally between 2 and 7 kilovolts. A magnetic field, oriented parallel to the source axis, is produced by a permanent magnet. A plasma is formed along the axis of the anode which traps electrons which, in turn, ionize gas in the source. The ions are extracted through the exit cathode. Under normal operation, the ion species produced by the Penning source are over 90% molecular ions. This disadvantage is however compensated for by the other advantages of the system.
One of the cathodes is a cup made of soft iron, enclosing most of the discharge space. The bottom of the cup has a hole through which most of the generated ions are ejected by the magnetic field into the acceleration space. The soft iron shields the acceleration space from the magnetic field, to prevent a breakdown.
Ions emerging from the exit cathode are accelerated through the potential difference between the exit cathode and the accelerator electrode. The schematic indicates that the exit cathode is at ground potential and the target is at high (negative) potential. This is the case in many sealed tube neutron generators. However, in cases when it is desired to deliver the maximum flux to a sample, it is desirable to operate the neutron tube with the target grounded and the source floating at high (positive) potential. The accelerator voltage is normally between 80 and 180 kilovolts.
The accelerating electrode has the shape of a long hollow cylinder. The ion beam has a slightly diverging angle (about 0.1 radian). The electrode shape and distance from target can be chosen so the entire target surface is bombarded with ions. Acceleration voltages of up to 200 kV are achievable.
The ions pass through the accelerating electrode and strike the target. When ions strike the target, 2–3 electrons per ion are produced by secondary emission. In order to prevent these secondary electrons from being accelerated back into the ion source, the accelerator electrode is biased negative with respect to the target. This voltage, called the suppressor voltage, must be at least 500 volts and may be as high as a few kilovolts. Loss of suppressor voltage will result in damage, possibly catastrophic, to the neutron tube.
Some neutron tubes incorporate an intermediate electrode, called the focus or extractor electrode, to control the size of the beam spot on the target. The gas pressure in the source is regulated by heating or cooling the gas reservoir element. | 3 | Nuclear Fusion |
Micromagnetics is a field of physics dealing with the prediction of magnetic behaviors at sub-micrometer length scales. The length scales considered are large enough for the atomic structure of the material to be ignored (the continuum approximation), yet small enough to resolve magnetic structures such as domain walls or vortices.
Micromagnetics can deal with static equilibria, by minimizing the magnetic energy, and with dynamic behavior, by solving the time-dependent dynamical equation. | 7 | Magnetic Ordering |
The spin-orbit interaction is the primary source of magnetocrystalline anisotropy. It is basically the orbital motion of the electrons which couples with crystal electric field giving rise to the first order contribution to magnetocrystalline anisotropy. The second order arises due to the mutual interaction of the magnetic dipoles. This effect is weak compared to the exchange interaction and is difficult to compute from first principles, although some successful computations have been made. | 7 | Magnetic Ordering |
Hari Reddi received his PhD from the University of Delhi in reproductive endocrinology under the mentorship of M.R.N. Prasad. Reddi did postdoctoral work with [http://www.uchospitals.edu/news/2004/20040602-williams-ashman.html Howard Guy Williams-Ashman] at the Johns Hopkins University School of Medicine. Reddi was also a student of Charles Brenton Huggins, the winner of the 1966 Nobel Prize with Peyton Rous for the endocrine regulation of cancer. | 2 | Tissue Engineering |
Degradation can be detected before serious cracks are seen in a product by using infrared spectroscopy, which is able to detect chemical species formed by photo-oxidation. In particular, peroxy-species and carbonyl groups have distinct absorption bands.
In the example shown at left, carbonyl groups were easily detected by IR spectroscopy from a cast thin film. The product was a road cone made by rotational moulding in LDPE, which had cracked prematurely in service. Many similar cones also failed because an anti-UV additive had not been used during processing. Other plastic products which failed included polypropylene mancabs used at roadworks which cracked after service of only a few months.
The effects of degradation can also be characterized through scanning electron microscopy (SEM). For example, through SEM, defects like cracks and pits can be directly visualized, as shown at right. These samples were exposed to 840 hours of exposure to UV light and moisture using a test chamber. Crack formation is often associated with degradation, such that materials that do not display significant cracking behavior, such as HDPE in the right example, are more likely to be stable against photooxidation compared to other materials like LDPE and PP. However, some plastics that have undergone photooxidation may also appear smoother in an SEM image, with some defects like grooves having disappeared afterwards. This is seen in polystyrene in the right example. | 8 | Ultraviolet Radiation |
An excess heat observation is based on an energy balance. Various sources of energy input and output are continuously measured. Under normal conditions, the energy input can be matched to the energy output to within experimental error. In experiments such as those run by Fleischmann and Pons, an electrolysis cell operating steadily at one temperature transitions to operating at a higher temperature with no increase in applied current. If the higher temperatures were real, and not an experimental artifact, the energy balance would show an unaccounted term. In the Fleischmann and Pons experiments, the rate of inferred excess heat generation was in the range of 10–20% of total input, though this could not be reliably replicated by most researchers. Researcher Nathan Lewis discovered that the excess heat in Fleischmann and Ponss original paper was not measured, but estimated from measurements that didnt have any excess heat.
Unable to produce excess heat or neutrons, and with positive experiments being plagued by errors and giving disparate results, most researchers declared that heat production was not a real effect and ceased working on the experiments. In 1993, after their original report, Fleischmann reported "heat-after-death" experiments—where excess heat was measured after the electric current supplied to the electrolytic cell was turned off. This type of report has also become part of subsequent cold fusion claims. | 3 | Nuclear Fusion |
Targeted temperature management is used during open-heart surgery because it decreases the metabolic needs of the brain, heart, and other organs, reducing the risk of damage to them. The patient is given medication to prevent shivering. The body is then cooled to 25–32 °C (79–89 °F). The heart is stopped and an external heart-lung pump maintains circulation to the patient's body. The heart is cooled further and is maintained at a temperature below 15 °C (60 °F) for the duration of the surgery. This very cold temperature helps the heart muscle to tolerate its lack of blood supply during the surgery. | 1 | Cryobiology |
Isocyanic acid can be made by protonation of the cyanate anion, such as from salts like potassium cyanate, by either gaseous hydrogen chloride or acids such as oxalic acid.
HNCO also can be made by the high-temperature thermal decomposition of the trimer cyanuric acid:
In the reverse of the famous synthesis of urea by Friedrich Wöhler,
isocyanic acid is produced and rapidly trimerizes to cyanuric acid. | 4 | Acids + Bases |
Cell types differentiated from pluripotent stem cells (PSCs) are being evaluated as preclinical in vitro models of Human diseases. Human cell types in a dish provide an alternative to traditional preclinical assays using animal, human immortalized cells or primary cultures from biopsies, which have their limitations. Clinically relevant cell types i.e. cell type affected in diseases are a major focus of research, this includes hepatocytes, Langerhans islet beta-cells, cardiomyocytes and neurons. Drug screen are performed on miniaturized cell culture in multiwell-plates or on a chip. | 2 | Tissue Engineering |
Intestinal organoids have thus far been among the gut organoids generated directly from intestinal tissues or pluripotent stem cells. One way human pluripotent stem cells can be driven to form intestinal organoids is through first the application of activin A to drive the cells into a mesoendodermal identity, followed by the pharmacological upregulation of Wnt3a and Fgf4 signaling pathways as they have been demonstrated to promote posterior gut fate. Intestinal organoids have also been generated from intestinal stem cells, extracted from adult tissue and cultured in 3D media. These adult stem cell-derived organoids are often referred to as enteroids or colonoids, depending on their segment of origin, and have been established from both the human and murine intestine. Intestinal organoids consist of a single layer of polarized intestinal epithelial cells surrounding a central lumen. As such, recapitulate the crypt-villus structure of the intestine, by recapitulating its function, physiology and organization, and maintaining all the cell types found normally in the structure including intestinal stem cells. Thus, intestinal organoids are a valuable model to study intestinal nutrient transport, drug absorption and delivery, nanomaterials and nanomedicine, incretin hormone secretion, and infection by various enteropathogens. For example, Qun Wang's team rationally designed artificial virus nanoparticles as oral drug delivery vehicles (ODDVs) with gut organoid-derived mucosal models and demonstrated a new concept of using newly established colon organoids as tools for high-throughput drug screening, toxicity testing, and oral drug development. Intestinal organoids also recapitulate the crypt-Villus structure to such a high degree of fidelity that they have been successfully transplanted to mouse intestines, and are hence highly regarded as a valuable model for research. One of the fields of research that intestinal organoids have been utilized is that of stem cell niche. Intestinal organoids were used to study the nature of the intestinal stem cell niche, and research done with them demonstrated the positive role IL-22 has in maintaining in intestinal stem cells, along with demonstrating the roles of other cell types like neurons and fibroblasts in maintenance of intestinal stem cells. In the field of infection biology, different intestinal organoid-based model systems have been explored. On one hand, organoids can be infected in bulk by simply mixing them with the enteropathogen of interest. However, to model infection via a more natural route starting from the intestinal lumen, microinjection of the pathogen is required. In addition, the polarity of intestinal organoids can be inverted, and they can even be dissociated into single cells and cultured as 2D monolayers in order to make both the apical and basolateral sides of the epithelium more easily accessible. Intestinal organoids have also demonstrated therapeutic potential.
In order to more accurately recapitulate the intestine in vivo, co-cultures of intestinal organoids and immune cells have been developed. Furthermore, organ-on-a-chip models combine intestinal organoids with other cell types such as endothelial or immune cells as well as peristaltic flow. | 2 | Tissue Engineering |
The sample (fruits, vegetables, tobacco, etc.) is homogenized and centrifuged with a reagent and agitated for 1 minute. The reagents used depend on the type of sample to be analyzed. Following this, the sample is put through a dispersive solid phase extraction cleanup prior to analysis by gas-liquid chromatography or liquid-liquid chromatography.
Samples prepared using the QuEChERS method can be processed more quickly using a homogenization instrument. Such instruments can homogenize the food sample in a centrifuge tube, then agitate the sample with the reagent of choice, before moving the extracted sample for centrifuging. By using such an instrument, the samples can be moved through the QuEChERS method more quickly.
Some modifications to the original QuEChERS method had to be introduced to ensure efficient extraction of pH-dependent compounds (e.g., phenoxyalkanoic acids), to minimize degradation of susceptible compounds (e.g., base and acid labile pesticides) and to expand the spectrum of matrices covered. | 5 | Separation Processes |
The potential of using cell microencapsulation in successful clinical applications can be realized only if several requirements encountered during the development process are optimized such as the use of an appropriate biocompatible polymer to form the mechanically and chemically stable semi-permeable matrix, production of uniformly sized microcapsules, use of an appropriate immune-compatible polycations cross-linked to the encapsulation polymer to stabilized the capsules, selection of a suitable cell type depending on the situation. | 2 | Tissue Engineering |
Mostly, SIRs have been investigated and used for the recovery of heavy metals. Applications include the removal of cadmium, vanadium, copper, chrome, iridium, etc. | 5 | Separation Processes |
The abundance of total alpha elements in stars is usually expressed in terms of logarithms, with astronomers customarily using a square bracket notation:
where is the number of alpha elements per unit volume, and is the number of iron nuclei per unit volume. It is for the purpose of calculating the number that which elements are to be considered "alpha elements" becomes contentious. Theoretical galactic evolution models predict that early in the universe there were more alpha elements relative to iron. | 3 | Nuclear Fusion |