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Possible complications may include: infection, bleeding, dysrhythmias and high blood sugar. One review found an increased risk of pneumonia and sepsis but not the overall risk of infection. Another review found a trend towards increased bleeding but no increase in severe bleeding. Hypothermia induces a "cold diuresis" which can lead to electrolyte abnormalities – specifically hypokalemia, hypomagnesaemia, and hypophosphatemia, as well as hypovolemia. | 1 | Cryobiology |
dNovo, a Silicon-valley based company, was founded in 2018 and participated in the Y Combinator accelerator. The company has demonstrated its technology by growing a patch of human hair on a mouse. | 2 | Tissue Engineering |
* Theodore von Karman Medal, 1976
* Otto Laporte Award, 1977
* Worcester Reed Warner Medal, 1984
* Jean-Leonard-Marie Poiseuille Award, 1986
* Timoshenko Medal, 1991
* Lissner Award for Bioengineering, from ASME
* Borelli Medal, from ASB
* Landis Award, from Microcirculation Society
* Alza Award, from BMES
* Melville Medal, 1994
* United States National Academy of Engineering Founders Award (NAE Founders Award), 1998
* National Medal of Science, 2000
* Fritz J. and Dolores H. Russ Prize, 2007 ("for the characterization and modeling of human tissue mechanics and function leading to prevention and mitigation of trauma.")
* Revelle Medal, from UC San Diego, 2016
Fung was elected to the United States National Academy of Sciences (1993), the National Academy of Engineering (1979), the Institute of Medicine (1991), the Academia Sinica (1968), and was a Foreign Member of the Chinese Academy of Sciences (1994 election). | 2 | Tissue Engineering |
In 1954, there was a program started at New York University called the Division of Research. It was a small program that included personnel from the Institute of Mathematical Sciences at New York University. | 3 | Nuclear Fusion |
Aggressiveness of treatment is matched to the degree of hypothermia. Treatment ranges from noninvasive, passive external warming to active external rewarming, to active core rewarming. In severe cases resuscitation begins with simultaneous removal from the cold environment and management of the airway, breathing, and circulation. Rapid rewarming is then commenced. Moving the person as little and as gently as possible is recommended as aggressive handling may increase risks of a dysrhythmia.
Hypoglycemia is a frequent complication and needs to be tested for and treated. Intravenous thiamine and glucose is often recommended, as many causes of hypothermia are complicated by Wernicke's encephalopathy.
The UK National Health Service advises against putting a person in a hot bath, massaging their arms and legs, using a heating pad, or giving them alcohol. These measures can cause a rapid fall in blood pressure and potential cardiac arrest. | 1 | Cryobiology |
A major issue is how many embryos should be transferred, since placement of multiple embryos carries a risk of multiple pregnancy. While the past physicians placed multiple embryos to increase the chance of pregnancy, this approach has fallen out of favor. Professional societies, and legislatures in many countries, have issued guidelines or laws to curtail the practice. There is low to moderate evidence that making a double embryo transfer during one cycle achieves a higher live birth rate than a single embryo transfer; but making two single embryo transfers in two cycles has the same live birth rate and would avoid multiple pregnancies.
The appropriate number of embryos to be transferred depends on the age of the woman, whether it is the first, second or third full IVF cycle attempt and whether there are top-quality embryos available. According to a guideline from The National Institute for Health and Care Excellence (NICE) in 2013, the number of embryos transferred in a cycle should be chosen as in following table: | 1 | Cryobiology |
The reaction mechanism is that of the related Hofmann degradation.
At first the carbonic acid amide (1) reacts with the sodium hypochlorite. After separate water and chloride an amine with a free bond is built 2. The intermediate (3) is generated by rearrangement. At this point two different mechanisms are possible. In the mechanism above two methanol molecules reacts with the intermediate. So is the compound (4) generated. After this carbon dioxide, water, ammonium and methanol are separated in different steps. At least it is protonated into an aldehyde (5).
Until the intermediate (3) the mechanism is the same like above. Then only one methanol-atom is added 4. With a protonation water, methanol and carbon dioxide are separated. An ammonium ion (5) is generated. During the hydrolysis a hydroxylic group is built 6. An aldehyde (7) is generated by separating an ammonium ion. | 6 | Carbohydrates |
Raytec Vision is a camera and sensor-based manufacturer based in Parma and specialized in food sorting. The applications of Raytec Vision's machines are many: tomatoes, tubers, fruit, fresh cut, vegetables and confectionery products. Each machine can separate good products from wastes, foreign bodies and defects and guarantees high levels of food safety for the final consumer. | 5 | Separation Processes |
By the late 1960s, radium was phased out and replaced with safer alternatives.
Tritium was used on and the original Panerai Luminor dive watch Radiomir and almost all Swiss watches from 1960 to 1998 when it was banned. Tritium-based substances ceased to be used by Omega SA in 1997.
In the 21st century, one radioluminescent alternative for afterglow pigments requiring radiation protection is being produced and used for watches and other uses. These are tritium-based devices called "gaseous tritium light source" (GTLS). GTLS are made using sturdy (often glass) containers internally coated with a phosphor layer and filled with tritium gas before the containers are permanently sealed. They have the advantage of being self-powered and producing a consistent luminosity that does not gradually fade during the night. However, GTLS contain radioactive tritium gas that has a half-life of slightly over 12.3 years. Additionally, phosphor degradation will cause the brightness of a tritium container to drop by more during that period. The more tritium that is initially inserted in the container, the brighter it is to begin with, and the longer its useful life. This means the intensity of the tritium-powered light source will slowly fade, generally becoming too dim to be useful for dark adapted human eyes after 20 to 30 years. | 0 | Luminescence |
A low-FODMAP diet consists of the global restriction of all fermentable carbohydrates (FODMAPs), and is recommended only for a short time. A low-FODMAP diet is recommended for managing patients with irritable bowel syndrome (IBS) and can reduce digestive symptoms of IBS, including bloating and flatulence.
Several studies have found a low-FODMAP diet to improve digestive symptoms in adults with irritable bowel syndrome, but its long-term use can have negative effects, because it has a detrimental impact on the gut microbiota and metabolome. It should only be used for short periods and under the advice of a specialist. More study is needed to evaluate its effectiveness in children with irritable bowel syndrome. Small studies (which are susceptible to bias) show little evidence of its effectiveness in treating functional symptoms of inflammatory bowel disease (IBD). More study is needed to assess the true impact of this diet on health. | 6 | Carbohydrates |
Low-pressure mercury-vapor lamps generate primarily 254 nm UVC energy, and are most commonly used in disinfection applications. Operated at lower temperatures and with less voltage than medium-pressure lamps, they, like all UV sources, require shielding when operated to prevent excess exposure of skin and eyes. | 8 | Ultraviolet Radiation |
DSSCs degrade when exposed to light. In 2014 air infiltration of the commonly-used amorphous Spiro-MeOTAD hole-transport layer was identified as the primary cause of the degradation, rather than oxidation. The damage could be avoided by the addition of an appropriate barrier.
The barrier layer may include UV stabilizers and/or UV absorbing luminescent chromophores (which emit at longer wavelengths which may be reabsorbed by the dye) and antioxidants to protect and improve the efficiency of the cell. | 8 | Ultraviolet Radiation |
Mictomagnetism is a spin system in which various exchange interactions are mixed. It is observed in several kinds of alloys, including Cu–Mn, Fe–Al and Ni–Mn alloys. Cooled in zero magnetic field, these materials have low remanence and coercivity. Cooled in a magnetic field, they have much larger remanence, and the hysteresis loop is shifted in the direction opposite to the field (an effect similar to exchange bias). | 7 | Magnetic Ordering |
Since luminescent ink or luminescent paper are only delivered to specialist printers, tagging also serves as an anti-counterfeiting measure, similar to the practice on banknotes. | 0 | Luminescence |
Practical engineering designs must first take into account safety as the primary goal. All designs should incorporate passive cooling in combination with refractory materials to prevent melting and reconfiguration of fissionables into geometries capable of un-intentional criticality. Blanket layers of Lithium bearing compounds will generally be included as part of the design to generate Tritium to allow the system to be self-supporting for one of the key fuel element components. Tritium, because of its relatively short half-life and extremely high radioactivity, is best generated on-site to obviate the necessity of transportation from a remote location. D-T fuel can be manufactured on-site using Deuterium derived from heavy water production and Tritium generated in the hybrid reactor itself. Nuclear spallation to generate additional neutrons can be used to enhance the fission output, with the caveat that this is a tradeoff between the number of neutrons (typically 20-30 neutrons per spallation event) against a reduction of the individual energy of each neutron. This is a consideration if the reactor is to use natural Thorium as a fuel. While high energy (0.17c) neutrons produced from fusion events are capable of directly causing fission in both Thorium and U, the lower energy neutrons produced by spallation generally cannot. This is a tradeoff that affects the mixture of fuels against the degree of spallation used in the design. | 3 | Nuclear Fusion |
Black light incandescent lamps are also made from an incandescent light bulb with a filter coating which absorbs most visible light. Halogen lamps with fused quartz envelopes are used as inexpensive UV light sources in the near UV range, from 400 to 300 nm, in some scientific instruments. Due to its black-body spectrum a filament light bulb is a very inefficient ultraviolet source, emitting only a fraction of a percent of its energy as UV. | 8 | Ultraviolet Radiation |
*9,10-Diphenylanthracene (DPA) emits blue light
*9-(2-Phenylethenyl) anthracene emits teal light
*1-Chloro-9,10-diphenylanthracene (1-chloro(DPA)) and 2-chloro-9,10-diphenylanthracene (2-chloro(DPA)) emit blue-green light more efficiently than nonsubstituted DPA
*9,10-Bis(phenylethynyl)anthracene (BPEA) emits green light with maximum at 486 nm
*1-Chloro-9,10-bis(phenylethynyl)anthracene emits yellow-green light, used in 30-minute high-intensity Cyalume sticks
*2-Chloro-9,10-bis(phenylethynyl)anthracene emits green light, used in 12-hour low-intensity Cyalume sticks
*1,8-Dichloro-9,10-bis(phenylethynyl)anthracene emits yellow light, used in Cyalume sticks
*Rubrene emits orange-yellow at 550 nm
*2,4-Di-tert-butylphenyl 1,4,5,8-tetracarboxynaphthalene diamide emits deep red light, together with DPA is used to produce white or hot-pink light, depending on their ratio
*Rhodamine B emits red light. It is rarely used, as it breaks down in contact with CPPO, shortening the shelf life of the mixture.
*5,12-Bis(phenylethynyl)naphthacene emits orange light
*Violanthrone emits orange light at 630 nm
*16,17-(1,2-Ethylenedioxy)violanthrone emits red at 680 nm
*16,17-Dihexyloxyviolanthrone emits infrared at 725 nm
*16,17-Butyloxyviolanthrone emits infrared
*N,N′-Bis(2,5,-di-tert-butylphenyl)-3,4,9,10-perylenedicarboximide emits red
*1-(N,N-Dibutylamino)anthracene emits infrared
*6-Methylacridinium iodide emits infrared | 0 | Luminescence |
Although the concentration of the ozone in the ozone layer is very small, it is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation coming from the Sun. Extremely short or vacuum UV (10–100 nm) is screened out by nitrogen. UV radiation capable of penetrating nitrogen is divided into three categories, based on its wavelength; these are referred to as UV-A (400–315 nm), UV-B (315–280 nm), and UV-C (280–100 nm).
UV-C, which is very harmful to all living things, is entirely screened out by a combination of dioxygen (< 200 nm) and ozone (> about 200 nm) by around altitude. UV-B radiation can be harmful to the skin and is the main cause of sunburn; excessive exposure can also cause cataracts, immune system suppression, and genetic damage, resulting in problems such as skin cancer. The ozone layer (which absorbs from about 200 nm to 310 nm with a maximal absorption at about 250 nm) is very effective at screening out UV-B; for radiation with a wavelength of 290 nm, the intensity at the top of the atmosphere is 350 million times stronger than at the Earths surface. Nevertheless, some UV-B, particularly at its longest wavelengths, reaches the surface, and is important for the skins production of vitamin D in mammals.
Ozone is transparent to most UV-A, so most of this longer-wavelength UV radiation reaches the surface, and it constitutes most of the UV reaching the Earth. This type of UV radiation is significantly less harmful to DNA, although it may still potentially cause physical damage, premature aging of the skin, indirect genetic damage, and skin cancer. | 8 | Ultraviolet Radiation |
A rudimentary understanding of muscle tissue began to develop as early as 1835, when embryonic myogenesis was first described. In the 1860s, it was shown that muscle is capable of regeneration and an experimental regeneration was conducted to better understand the specific method by which this was done in vivo. Following this discovery, muscle generation and degeneration in man were described for the first time. Researchers consequently assessed several aspects of muscle regeneration in vivo, including "the continuous or discontinuous regeneration depending on tissue type" to increase functional understanding of the phenomena. It was not until the 1960s, however, that researchers determined what components were required for muscle regeneration. | 2 | Tissue Engineering |
The Society for Cryobiology is an international scientific society that was founded in 1964. Its objectives are to promote research in low temperature biology, to improve scientific understanding in this field, and to disseminate and aid in the application of this knowledge. The Society also publishes a journal called Cryobiology.
The society has hosted 60 annual meetings to date, with the 2024 annual meeting being held in Washington. The three-day event will host over 350 delegates from more than 35 countries. | 1 | Cryobiology |
Fusion ignition is the point at which a nuclear fusion reaction becomes self-sustaining. This occurs when the energy being given off by the reaction heats the fuel mass more rapidly than it cools. In other words, fusion ignition is the point at which the increasing self-heating of the nuclear fusion removes the need for external heating.
This is quantified by the Lawson criterion.
Ignition can also be defined by the fusion energy gain factor.
In the laboratory, fusion ignition defined by the Lawson criterion was first achieved in August 2021,
and ignition defined by the energy gain factor was achieved in December 2022,
both by the U.S. National Ignition Facility. | 3 | Nuclear Fusion |
It is easily produced by igniting a mixture of zinc and sulfur. Since zinc sulfide is insoluble in water, it can also be produced in a precipitation reaction. Solutions containing Zn salts readily form a precipitate ZnS in the presence of sulfide ions (e.g., from HS).
:Zn + S → ZnS
This reaction is the basis of a gravimetric analysis for zinc. | 0 | Luminescence |
Galactogen is a polymer of galactose with species-specific structural variations. In this polysaccharide, the D-galactose are predominantly β (1→3) and β (1→6) linked; however some species also have β (1→2) and β (1→4). The galactogen of the aquatic Basommatophora (e.g. Lymnaea, Biomphalaria) is highly branched with only 5-8 % of the sugar residues in linear sections, and β(1→3) and β(1→6) bonds alternate more-or-Iess regularly. In the terrestrial Stylommatophora (e.g. Helix, Arianta, Cepaea, Achatina) up to 20% of the sugar residues are linear β(1→3) bound. The galactogen of Ampullarius sp species has an unusually large proportion of linearly arranged sugars, with 5% β(1→3), 26% β(1→6), and 10% β(1→2). Other analyses in Helix pomatia suggested a dichotomous structure, where each galactopyranose unit bears a branch or side chain.
Molecular weight determinations in galactogen extracted from the eggs of Helix pomatia and Limnaea stagnalis were estimated in 4x10 and 2.2x10, respectively. In these snails galactogen contains only D-galactose. Depending upon the origin of the galactogen, apart from D-galactose, L-galactose, L-fucose, D-glucose, L-glucose and phosphate residues may also be present; for instance, the galactogen from Ampullarius sp. contains 98% of D-galacotose and 2% of L- fucose, and the one isolated from Pomacea maculata eggs consist in 68% of D-galactose and 32% of D-glucose. Phosphate-substituted galactose residues are found in the galactogen of individual species from various snail genera such as Biomphalaria, Helix and Cepaea. Therefore, current knowledge indicates it could be considered either a homopolysaccharide of or a heteropolysaccharide dominated by galactose. | 6 | Carbohydrates |
The contact angle formed between a liquid and solid phase will exhibit a range of contact angles that are possible. There are two common methods for measuring this range of contact angles. The first method is referred to as the tilting base method. Once a drop is dispensed on the surface with the surface level, the surface is then tilted from 0° to 90°. As the drop is tilted, the downhill side will be in a state of imminent wetting while the uphill side will be in a state of imminent dewetting. As the tilt increases the downhill contact angle will increase and represents the advancing contact angle while the uphill side will decrease; this is the receding contact angle. The values for these angles just prior to the drop releasing will typically represent the advancing and receding contact angles. The difference between these two angles is the contact angle hysteresis.
The second method is often referred to as the add/remove volume method. When the maximum liquid volume is removed from the drop without the interfacial area decreasing the receding contact angle is thus measured. When volume is added to the maximum before the interfacial area increases, this is the advancing contact angle. As with the tilt method, the difference between the advancing and receding contact angles is the contact angle hysteresis. Most researchers prefer the tilt method; the add/remove method requires that a tip or needle stay embedded in the drop which can affect the accuracy of the values, especially the receding contact angle. | 7 | Magnetic Ordering |
Upon absorption of light, fluorescent materials emit light upon of a longer wavelength (lower energy) than the absorbed radiation, but cease to do so once immediately, when the illumination is stopped. The tagging of stamps uses substances that absorb ultraviolet light of wavelengths between 300 nm and 450 nm ("Black light", UVA, long-wave UV) and emit light in the visible spectrum. Under UV illumination they usually glow a greenish or yellowish colour.
It must not be confused with the "whitening" of paper which is achieved by adding optical brighteners that usually re-emit light in the blue region of the spectrum, making the paper appear whiter by compensating a perceived deficit in reflected colours of these wavelengths. | 0 | Luminescence |
A bioartificial heart is an engineered heart that contains the extracellular structure of a decellularized heart and cellular components from a different source. Such hearts are of particular interest for therapy as well as research into heart disease. The first bioartificial hearts were created in 2008 using cadaveric rat hearts. In 2014, human-sized bioartificial pig hearts were constructed. Bioartificial hearts have not been developed yet for clinical use, although the recellularization of porcine hearts with human cells opens the door to xenotransplantation. | 2 | Tissue Engineering |
An important application of the Néel effect is as a current sensor, measuring the magnetic field radiated by a conductor with a current; this is the principle of Néel effect current sensors. The Néel effect allows the accurate measurement of currents with very low-frequency-type sensors in a current transformer without contact.
The transducer of a Néel-effect current sensor consists of a coil with a core of superparamagnetic nanoparticles. The coil is traversed by a current excitation:
In the presence of an external magnetic field to be measured:
the transducer transposes (with the Néel effect) the information to be measured, H (f) around a carrier frequency, the harmonic of order 2 excitation current 2:
which is simpler. The electromotive force generated by the coil is proportional to the magnetic field to measure:
and to the square of the excitation current:
To improve the measurement's performance (such as linearity and sensitivity to temperature and vibration), the sensor includes a second permanent winding-reaction against it to cancel the second harmonic. The relationship of the current reaction against the primary current is proportional to the number of turns against reaction: | 7 | Magnetic Ordering |
The magnetostriction characterizes the shape change of a ferromagnetic material during magnetization, whereas the inverse magnetostrictive effect characterizes the change of sample magnetization (for given magnetizing field strength ) when mechanical stresses are applied to the sample. | 7 | Magnetic Ordering |
Helimagnetism is a form of magnetic ordering where spins of neighbouring magnetic moments arrange themselves in a spiral or helical pattern, with a characteristic turn angle of somewhere between 0 and 180 degrees. It results from the competition between ferromagnetic and antiferromagnetic exchange interactions. It is possible to view ferromagnetism and antiferromagnetism as helimagnetic structures with characteristic turn angles of 0 and 180 degrees respectively. Helimagnetic order breaks spatial inversion symmetry, as it can be either left-handed or right-handed in nature.
Strictly speaking, helimagnets have no permanent magnetic moment, and as such are sometimes considered a complicated type of antiferromagnet. This distinguishes helimagnets from conical magnets, (e.g. Holmium below 20 K) which have spiral modulation in addition to a permanent magnetic moment. Helimagnets can be characterized by the distance it takes for the spiral to complete one turn. In analogy to the pitch of screw thread, the period of repetition is known as the "pitch" of the helimagnet. If the spirals period is some rational multiple of the crystals unit cell, the structure is commensurate, like the structure originally proposed for MnO. On the other hand, if the multiple is irrational, the magnetism is incommensurate, like the updated MnO structure.
Helimagnetism was first proposed in 1959, as an explanation of the magnetic structure of manganese dioxide. Initially applied to neutron diffraction, it has since been observed more directly by Lorentz electron microscopy. Some helimagnetic structures are reported to be stable up to room temperature. Like how ordinary ferromagnets have domain walls that separate individual magnetic domains, helimagnets have their own classes of domain walls which are characterized by topological charge.
Many helimagnets have a chiral cubic structure, such as the FeSi (B20) crystal structure type. In these materials, the combination of ferromagnetic exchange and the Dzyaloshinskii–Moriya interaction leads to helixes with relatively long periods. Since the crystal structure is noncentrosymetric even in the paramagnetic state, the magnetic transition to a helimagnetic state does not break inversion symmetry, and the direction of the spiral is locked to the crystal structure.
On the other hand, helimagnetism in other materials can also be based on frustrated magnetism or the RKKY interaction. The result is that centrosymmetric structures like the MnP-type (B31) compounds can also exhibit double-helix type helimagnetism where both left and right handed spirals coexist. For these itinerant helimagnets, the direction of the helicity can be controlled by applied electric currents and magnetic fields. | 7 | Magnetic Ordering |
An example of magnetoresistance due to direct action of magnetic field on electric current can be studied on a Corbino disc (see Figure).
It consists of a conducting annulus with perfectly conducting rims. Without a magnetic field, the battery drives a radial current between the rims. When a magnetic field perpendicular to the plane of the annulus is applied, (either into or out of the page) a circular component of current flows as well, due to Lorentz force. Initial interest in this problem began with Boltzmann in 1886, and independently was re-examined by Corbino in 1911.
In a simple model, supposing the response to the Lorentz force is the same as for an electric field, the carrier velocity v is given by:
where μ is the carrier mobility. Solving for the velocity, we find:
where the effective reduction in mobility due to the B-field (for motion perpendicular to this field) is apparent. Electric current (proportional to the radial component of velocity) will decrease with increasing magnetic field and hence the resistance of the device will increase. Critically, this magnetoresistive scenario depends sensitively on the device geometry and current lines and it does not rely on magnetic materials.
In a semiconductor with a single carrier type, the magnetoresistance is proportional to (1 + (μB)), where μ is the semiconductor mobility (units m·V·s or T) and B is the magnetic field (units teslas). Indium antimonide, an example of a high mobility semiconductor, could have an electron mobility above 4 m·V·s at 300 K. So in a 0.25 T field, for example the magnetoresistance increase would be 100%. | 7 | Magnetic Ordering |
Excimer lamps emit narrow-band UVC and vacuum-ultraviolet radiation at a variety of wavelengths depending on the medium. They are mercury-free and reach full output quicker than a mercury lamp, and generate less heat. Excimer emission at 207 and 222 nm appears to be safer than traditional 254 nm germicidal radiation, due to greatly reduced penetration of these wavelengths in human skin. | 8 | Ultraviolet Radiation |
Organ printing for medical applications is still in the developmental stages. Thus, the long term impacts of organ printing have yet to be determined. Researchers hope that organ printing could decrease the organ transplant shortage. There is currently a shortage of available organs, including liver, kidneys, and lungs. The lengthy wait time to receive life saving organs is one of the leading causes of death in the United States, with nearly one third of deaths each year in the United States that could be delayed or prevented with organ transplants. Currently the only organ that has been 3D bioprinted and successfully transplanted into a human is a bladder. The bladder was formed from the host's bladder tissue. Researchers have proposed that a potential positive impact of 3D printed organs is the ability to customize organs for the recipient. Developments enabling an organ recipient’s host cells to be used to synthesize organs decreases the risk of organ rejection.
The ability to print organs has decreased the demand for animal testing. Animal testing is used to determine the safety of products ranging from makeup to medical devices. Cosmetic companies are already using smaller tissue models to test new products on skin. The ability to 3D print skin reduces the need for animal trials for makeup testing. In addition, the ability to print models of human organs to test the safety and efficacy of new drugs further reduces the necessity for animal trials. Researchers at Harvard University determined that drug safety can be accurately tested on smaller tissue models of lungs. The company Organovo, which designed one of the initial commercial bioprinters in 2009, has displayed that biodegradable 3D tissue models can be used to research and develop new drugs, including those to treat cancer. An additional impact of organ printing includes the ability to rapidly create tissue models, therefore increasing productivity. | 2 | Tissue Engineering |
The black-white Bravais lattices characterize the translational symmetry of the structure like the typical Bravais lattices, but also contain additional symmetry elements. For black-white Bravais lattices, the number of black and white sites is always equal. There are 14 traditional Bravais lattices, 14 grey lattices, and 22 black-white Bravais lattices, for a total of 50 two-color lattices in three dimensions.
The table shows the 36 black-white Bravais lattices, including the 14 traditional Bravais lattices, but excluding the 14 gray lattices which look identical to the traditional lattices. The lattice symbols are those used for the traditional Bravais lattices. The suffix in the symbol indicates the mode of centering by the black (antisymmetry) points in the lattice, where s denotes edge centering. | 7 | Magnetic Ordering |
Barometric light is a name for the light that is emitted by a mercury-filled barometer tube when the tube is shaken. The discovery of this phenomenon in 1675 revealed the possibility of electric lighting. | 0 | Luminescence |
For higher grade applications such as ferrous metals, coal and industrial minerals, sensor-based ore sorting can be applied to create a final product. Pre-condition is, that the liberation allows for the creation of a sellable product. Undersize material is usually bypassed as product, but can also be diverted to the waste fraction, if the composition does not meet the required specifications. This is case and application dependent. | 5 | Separation Processes |
A related technique pumps deuterium gas through the wall of a palladium-silver alloy tubing. The palladium is electrolytically loaded with deuterium. In some experiments this produces fast neutrons that trigger further reactions. Other experimenters (Fralick et al.) also made claims of anomalous heat produced by this system. | 3 | Nuclear Fusion |
The MIRAGE Commission consists of three groups which tightly interact with each other.
The advisory board consists of leading scientists in glycobiology, who, for example, critically review the outcomes of the working group and promote the reporting guidelines within the community.
The working group seeks for external consultation and directly interacts with the glycomics community. The group members carry out defined subprojects (e.g. development and revision of guidelines) by focusing on specific research areas to fulfill the overall aims of the MIRAGE project.
The co-ordination team links the subprojects from the working group together and passes the outcomes to the advisory board for review. | 6 | Carbohydrates |
At least three biological pathways support trehalose biosynthesis. An industrial process can derive trehalose from corn starch. | 6 | Carbohydrates |
The LCP family or TagU family of proteins is a conserved family of phosphotransferases that are involved in the attachment of teichoic acid (TA) molecules to gram-positive cell wall or cell membrane. It was initially thought as the LytR (lytic repressor) component of a LytABC operon encoding autolysins, but the mechanism of regulation was later realized to be the production of TA molecules. It was accordingly renamed TagU.
The "LCP" acronym derives from three proteins initially identified to contain this domain, LytR (now TagU, ), cpsA ("Capsular polysaccharide expression regulator"), and psr ("PBP 5 synthesis repressor"). These proteins were mistaken as transcriptional regulators via different reasons, but all three of them are now known to be TagU-like enzymes. While TagU itself only attaches TA molecules to the peptidoglycan cell wall (forming WTA), other LCP proteins may glycosylate cell wall proteins (A. oris LcpA, ) or attach TA molecules to a cell membrane anchor (forming LTA). Most, if not all, LCP proteins also have a secondary pyrophosphatase activity.
Typical TagU proteins are made up of an N-terminal transmembrane domain (for anchoring), an optional, non-conserved accessory domain (CATH 3tflA01), a core catalytic domain, and sometimes a C-terminal domain for which the structure is unknown. The core LCP domain is a magnesium-dependent enzyme. | 4 | Acids + Bases |
Twenty to fifty percent of hypothermia deaths are associated with paradoxical undressing. This typically occurs during moderate and severe hypothermia, as the person becomes disoriented, confused, and combative. They may begin discarding their clothing, which, in turn, increases the rate of heat loss.
Rescuers who are trained in mountain survival techniques are taught to expect this; however, people who die from hypothermia in urban environments who are found in an undressed state are sometimes incorrectly assumed to have been subjected to sexual assault.
One explanation for the effect is a cold-induced malfunction of the hypothalamus, the part of the brain that regulates body temperature. Another explanation is that the muscles contracting peripheral blood vessels become exhausted (known as a loss of vasomotor tone) and relax, leading to a sudden surge of blood (and heat) to the extremities, causing the person to feel overheated. | 1 | Cryobiology |
Mechanochromic luminescence (ML) references to intensity and/or color changes of (solid-state) luminescent materials induced by mechanical forces, such as rubbing, crushing, pressing, shearing, or smearing. Unlike "triboluminescence" which does not require additional excitation source other than force itself, ML is often manifested by external photoexcitation such as a UV lamp. The most common cause of ML is related to changes of intermolecular interactions of dyes and pigments, which gives rise to various strong (exciton splitting) and/or weak (Forster) excited state interactions. For example, a certain boron complex of [http://pubs.acs.org/doi/abs/10.1021/ja9097719 sunscreen compound] avobenzone exhibits reversible ML. A [http://pubs.rsc.org/en/Content/ArticleLanding/2012/JM/c2jm32809g recent detailed study] suggests that ML from the boron complex consists of two critical coupled steps: 1) generation of low energy exciton trap via mechanical perturbation; and 2) exciton migration from regions where photoexcitation results in a higher excited state. Since solid-state energy transfer can be very efficient, only a small fraction of the low-energy exciton traps is required when mechanical force is applied. As a result, for crystalline ML materials, XRD measurement may not able to detect changes before and after mechanical stimuli while its photoluminescence can be quite different. | 0 | Luminescence |
Gastric acid, gastric juice, or stomach acid is a digestive fluid formed within the stomach lining. With a pH between 1 and 3, gastric acid plays a key role in digestion of proteins by activating digestive enzymes, which together break down the long chains of amino acids of proteins. Gastric acid is regulated in feedback systems to increase production when needed, such as after a meal. Other cells in the stomach produce bicarbonate, a base, to buffer the fluid, ensuring a regulated pH. These cells also produce mucus – a viscous barrier to prevent gastric acid from damaging the stomach. The pancreas further produces large amounts of bicarbonate and secretes bicarbonate through the pancreatic duct to the duodenum to neutralize gastric acid passing into the digestive tract.
The primary active component of gastric acid is hydrochloric acid (HCl), which is produced by parietal cells in the gastric glands in the stomach. The secretion is a complex and relatively energetically expensive process. Parietal cells contain an extensive secretory network (called canaliculi) from which the "hydrochloric acid" is secreted into the lumen of the stomach. The pH of gastric acid is 1.5 to 3.5 in the human stomach lumen, a level maintained by the proton pump H/K ATPase. The parietal cell releases bicarbonate into the bloodstream in the process, which causes a temporary rise of pH in the blood, known as an alkaline tide.
The highly acidic environment in the stomach lumen degrades proteins (e.g., food). Peptide bonds, which comprise proteins, are labilized. The gastric chief cells of the stomach secrete enzymes for protein breakdown (inactive pepsinogen, and in infancy rennin). The low pH activates pepsinogen into the enzyme pepsin, which then aids digestion by breaking the amino acid bonds, a process called proteolysis. In addition, many microorganisms are inhibited or destroyed in an acidic environment, preventing infection or sickness. | 4 | Acids + Bases |
Excimer lamps are quasimonochromatic light sources operating over a wide range of wavelengths in the ultraviolet (UV) and vacuum ultraviolet (VUV) spectral regions. Operation of an excimer lamp is based on the formation of excited dimers (excimers), which spontaneously transiting from the excited state to the ground state result in the emission of UV photons. The spectral maximum of excimer lamp radiation is specified by a working excimer molecule:
Excimers are diatomic molecules (dimers) or polyatomic molecules that have stable excited electronic states and an unbound or weakly bound (thermally unstable) ground state. Initially, only homonuclear diatomic molecules with a stable excited state but a repulsive ground state were called excimers (excited dimers). The term "excimer" was later extended to refer any polyatomic molecule with a repulsive or weakly bound ground state. One can also come across the term "exciplex" (from "excited complex"). It is also an excimer molecule but not a homonuclear dimer. For instance, Xe*, Kr*, Ar* are excimer molecules, while XeCl*, KrCl*, XeBr*, ArCl*, XeCl* are referred to exciplex molecules. Dimers of rare gases and rare-gas–halogen dimers are the most spread and studied excimers. Rare-gas–halide trimers, metal excimers, metal–rare-gas excimers, metal–halide excimers, and rare-gas–oxide excimers are also known, but they are rarely used.
An excimer molecule can exist in an excited electronic state for a limited time, as a rule from a few to a few tens of nanoseconds. After that, an excimer molecule transits to the ground electronic state, while releasing the energy of internal electronic excitation in the form of a photon. Owing to a specific electronic structure of an excimer molecule, the energy gap between the lowest bound excited electronic state and the ground state amounts from 3.5 to 10 eV, depending on a kind of an excimer molecule and provides light emission in the UV and VUV spectral region. A typical spectral characteristic of excimer lamp radiation consists mainly of one intense narrow emission band. About 70–80% of the whole radiation power of an excimer lamp is concentrated in this emission band. The full width at half maximum of the emission band depends on a kind of an excimer molecule and excitation conditions and ranges within 2 to 15 nm. In fact, excimer lamps are sources of quasimonochromatic light. Therefore, such sources are suitable for spectral-selective irradiation and can even replace lasers in some cases. | 8 | Ultraviolet Radiation |
Another class of UV fluorescent bulb is designed for use in "bug zapper" flying insect traps. Insects are attracted to the UV light, which they are able to see, and are then electrocuted by the device. These bulbs use the same UV-A emitting phosphor blend as the filtered blacklight, but since they do not need to suppress visible light output, they do not use a purple filter material in the bulb. Plain glass blocks out less of the visible mercury emission spectrum, making them appear light blue-violet to the naked eye. These lamps are referred to by the designation "blacklight" or "BL" in some North American lighting catalogs. These types are not suitable for applications which require the low visible light output of "BLB" tubes lamps. | 8 | Ultraviolet Radiation |
Magnetocrystalline anisotropy has a great influence on industrial uses of ferromagnetic materials. Materials with high magnetic anisotropy usually have high coercivity, that is, they are hard to demagnetize. These are called "hard" ferromagnetic materials and are used to make permanent magnets. For example, the high anisotropy of rare-earth metals is mainly responsible for the strength of rare-earth magnets. During manufacture of magnets, a powerful magnetic field aligns the microcrystalline grains of the metal such that their "easy" axes of magnetization all point in the same direction, freezing a strong magnetic field into the material.
On the other hand, materials with low magnetic anisotropy usually have low coercivity, their magnetization is easy to change. These are called "soft" ferromagnets and are used to make magnetic cores for transformers and inductors. The small energy required to turn the direction of magnetization minimizes core losses, energy dissipated in the transformer core when the alternating current changes direction. | 7 | Magnetic Ordering |
Fresh blastocyst (day 5 to 6) stage transfer seems to be more effective than cleavage (day 2 or 3) stage transfer in assisted reproductive technologies. The Cochrane study showed a small improvement in live birth rate per couple for blastocyst transfers. This would mean that for a typical rate of 31% in clinics that use early cleavage stage cycles, the rate would increase to 32% to 41% live births if clinics used blastocyst transfer. Recent systematic review showed that along with selection of embryo, the techniques followed during transfer procedure may result in successful pregnancy outcome. The following interventions are supported by the literature for improving pregnancy rates:
Abdominal ultrasound guidance for embryo transfer
Removal of cervical mucus
Use of soft embryo transfer catheters
Placement of embryo transfer tip in the upper or middle (central) area of the uterine cavity, greater than 1 cm from the fundus, for embryo expulsion
Immediate ambulation once the embryo transfer procedure is completed | 1 | Cryobiology |
Many studies have proposed that induction of EMT is the primary mechanism by which epithelial cancer cells acquire malignant phenotypes that promote metastasis. Drug development targeting the activation of EMT in cancer cells has thus become an aim of pharmaceutical companies. | 2 | Tissue Engineering |
DPN is emerging as a powerful research tool for manipulating cells at subcellular resolution
* Stem cell differentiation
* Subcellular drug delivery
* Cell sorting
* Surface gradients
* Subcellular ECM protein patterns
* Cell adhesion | 2 | Tissue Engineering |
A mixing chamber where a mechanical agitator brings in intimate contact the feed solution and the solvent to carry out the transfer of solute(s). The mechanical agitator is equipped with a motor which drives a mixing and pumping turbine. This turbine draws the two phases from the settlers of the adjacent stages, mixes them, and transfers this emulsion to the associated settler.
The mixer may consists of one or multiple stages of mixing tanks. Common laboratory mixers consist of a single mixing stage, whereas industrial scale copper mixers may consist of up to three mixer stages where each stage performs a combined pumping and mixing action. Use of multiple stages allows a longer reaction time and also minimizes the short circuiting of unreacted material through the mixers. | 5 | Separation Processes |
According to the United States Environmental Protection Agency, "radioactive antiques [including watches] are usually not a health risk as long as they are intact and in good condition." However, radium is highly radioactive, emitting alpha, beta, and gamma radiation — the effects of which are particularly deleterious if inhaled or ingested since there is no shielding within the body. Indeed, the body treats radium as it does calcium, storing it in bone where it may cause bone degeneration and cancer.
Therefore, it is of the utmost importance that watches with radium dials should not be taken apart without proper training, technique, and facilities. Radium paint can be ingested by inhaling flaking paint particles. The alpha particles emitted by the radium, which is taken up in bone, will kill off surrounding bone tissue, resulting in a condition loosely referred to as radium jaw. Inhaled or ingested particles may deposit a high local dose with a risk of radiation-caused lung or gastrointestinal cancer. Penetrating gamma radiation produced by some dials also represents a significant health risk.
Although old radium dials generally no longer produce light, this is due to the breakdown of the crystal structure of the luminous zinc sulfide rather than the radioactive decay of the radium. The radium isotope (Ra) used has a half-life of about 1,600 years, so radium dials remain essentially just as radioactive as when originally painted 50 or 100 years ago, whether or not they remain luminous.
Radium dials held near the face have been shown to produce radiation doses in excess of 10 µSv / hour. After about 20 minutes this delivers the equivalent of one whole day's worth of normal background radiation. This rate probably only represents the dose rate from gamma emission, as the alpha emission will be stopped by the lacquer, or crystal, or case; hence, the dose rate following ingestion or inhalation of the dust could be much higher.
Chronic exposure to high levels of radium can result in an increased incidence of bone, liver, or breast cancer. Decaying radium also produces the gas radon, recognized as the second leading cause of lung cancer in the United States and the United Kingdom. A 2018 study by researchers from the University of Northampton found that a collection of 30 vintage military watches with radium dials kept in a small, unventilated room produced a radon concentration 134 times greater than the UK's recommended "safe" level.
Ingestion of radium has been linked to anemia, cataracts, broken teeth, and reduced bone growth. | 0 | Luminescence |
Prior to the early 1990s, the studies on different chemical and physical variables of sonoluminescence were all conducted using multi-bubble sonoluminescence (MBSL). This was a problem since all of the theories and bubble dynamics were based on single bubble sonoluminescence (SBSL) and researchers believed that the bubble oscillations of neighboring bubbles could affect each other. Single bubble sonoluminescence wasn't achieved until the early 1990s and allowed the study of the effects of various parameters on a single cavitating bubble. After many of the early theories were disproved, the remaining plausible theories can be classified into two different processes: electrical and thermal. | 0 | Luminescence |
Current RO membranes, thin-film composite (TFC) polyamide membranes, are being studied to find ways of improving their permeability. Through new imaging methods, researchers were able to make 3D models of membranes and examine how water flowed through them. They found that TFC membranes with areas of low flow significantly decreased water permeability. By ensuring uniformity of the membranes and allowing water to flow continuously without slowing down, membrane permeability could be improved by 30%-40%. | 5 | Separation Processes |
In addition to medical and psychological effects, many social implications exist for acid survivors, especially women. For example, such attacks usually leave victims handicapped in some way, rendering them dependent on either their spouse or family for everyday activities, such as eating and running errands. These dependencies are increased by the fact that many acid survivors are not able to find suitable work, due to impaired vision and physical handicap. This negatively impacts their economic viability, causing hardships on the families/spouses that care for them. As a result, divorce rates are high, with abandonment by husbands found in 25% of acid assault cases in Uganda (compared to only 3% of wives abandoning their disfigured husbands). Moreover, acid survivors who are single when attacked almost certainly become ostracized from society, effectively ruining marriage prospects. Some media outlets overwhelmingly avoid reporting acid attack violence, or the description of the attack is laconic or often implies that the act was inevitable or even justified. | 4 | Acids + Bases |
According to Afshin Molavi, in the early years of the revolution and following the mandating of the covering of hair by women in Iran, some women were threatened with acid attacks by Islamic vigilantes for failing to wear hijab.
Recently, acid assault in Iran has been met with increased sanctions. The Sharia code of qisas, or equivalence justice, required a caught perpetrator of acid violence to pay a fine and may be blinded with acid in both eyes. Under Iranian law, victims or their families can ask a courts permission to enact "qisas" either by taking the perpetrators life in murder cases or inflicting an equivalent injury on his or her body. One victim, Ameneh Bahrami, sentenced her attacker to be blinded in 2008. However, as of 31 July 2011, she pardoned her attacker, thereby absolving Majid Movahedi of his crime and halting the retributive justice of Qisas.
In October 2014, a series of acid attacks on women occurred in the city of Isfahan, resulting in demonstrations and arrests of journalists who had covered the attacks. The attacks were thought by many Iranians to be the work of conservative Islamist vigilantes, but the Iranian government denies this. | 4 | Acids + Bases |
A review in 2013 came to the result that infants resulting from IVF (with or without ICSI) have a relative risk of birth defects of 1.32 (95% confidence interval 1.24–1.42) compared to naturally conceived infants. In 2008, an analysis of the data of the National Birth Defects Study in the US found that certain birth defects were significantly more common in infants conceived through IVF, notably septal heart defects, cleft lip with or without cleft palate, esophageal atresia, and anorectal atresia; the mechanism of causality is unclear. However, in a population-wide cohort study of 308,974 births (with 6,163 using assisted reproductive technology and following children from birth to age five) researchers found: "The increased risk of birth defects associated with IVF was no longer significant after adjustment for parental factors." Parental factors included known independent risks for birth defects such as maternal age, smoking status, etc. Multivariate correction did not remove the significance of the association of birth defects and ICSI (corrected odds ratio 1.57), although the authors speculate that underlying male infertility factors (which would be associated with the use of ICSI) may contribute to this observation and were not able to correct for these confounders. The authors also found that a history of infertility elevated risk itself in the absence of any treatment (odds ratio 1.29), consistent with a Danish national registry study and "implicates patient factors in this increased risk." The authors of the Danish national registry study speculate: "our results suggest that the reported increased prevalence of congenital malformations seen in singletons born after assisted reproductive technology is partly due to the underlying infertility or its determinants." | 1 | Cryobiology |
The use of fibrin hydrogel in gene delivery (transfection) is studied to address essential factors controlling the delivery process such as fibrinogen and pDNA concentration in addition to significance of cell-mediated fibrin degradation for pursuing the potential of cell-transfection microarray engineering or in vivo gene transfer. Gene transfer is more successful in-gel than on-gel probably because of proximity of lipoplexes and target cells. Less cytotoxicity is observed due to less use of transfection agents like lipofectamine and steady degradation of fibrin. Consequently, each cell type requires optimization of fibrinogen and pDNA concentrations for higher transfection yields and studies towards high-throughput transfection microarray experiments are promising. | 2 | Tissue Engineering |
The main impregnation techniques are wet impregnation and dry impregnation. During wet impregnation, the porous particles are dissolved in the extractant and allowed to soak with the respective fluid. In this approach, the particles are either contacted with a precalculated amount of extractant, which completely soaks into the porous matrix, or the particles are contacted with an excess of extractant. After soaking, the remaining extractant, which is not inside the pores, is evaporated.
If the wet method is used, the extractant is dissolved in an additional solvent prior to impregnation. The porous particles are then dispersed in the extractant-solvent solution. After soaking the particles, the excess solvent can either be filtered off or evaporated. In the first case, an extractant-solvent mixture would be retained within the pores. This would be of interest for extractants which would be solid at design conditions when pure. In the second case, only the extractant would remain inside the pores. Figure 3 shows porous particles dispersed in an aqueous solution after wet impregnation. The cut-out in Figure 3 shows an enlarge segment of the surface of such an impregnated particle.
An additional, albeit not so frequently used technique is the modifier addition method. This technique relies on the use of an extractant/solvent/modifier system. The additional modifier is supposed to enhance the penetration of the extractant into the particle pores. The solvent is subsequently evaporated, leaving extractant and modifier in the particle pores.
Furthermore, the dynamic column method can be used. The particles are contacted with a solvent until they are completely soaked. This can be done prior or after packing into the column. The packed bed is then rinsed with the liquid extractant until inlet and outlet concentrations are the same. This approach is particularly interesting when particles are already packed in a column and shall be reused for a SIR application. | 5 | Separation Processes |
"In vitro" is a latin phrase whose literal translation is "within the glass." This term is used in the English language to describe a process which occurs outside of a living organism. Within the context of muscle tissue engineering, the term "in vitro" applies to the seeding of cells into a biomaterial scaffold with growth factors and nutrients, then culturing these constructs until a functional construct, such as myofibres, is developed. These developed constructs are then implanted into the wound site with the expectation that they will continue to proliferate and integrate into host muscle tissue. The goal of in vitro muscle tissue engineering is to increase the functionality of the tissue before it is ever implanted into the body, thus increasing mechanical properties and potential to thrive in the host body.
Abdulghani & Mitchell describe in vitro muscle tissue engineering as a concept with utilizes the same basic strategies of in vivo tissue engineering. The difference between the two methods, however, is the development of a fully functional tissue engineered muscle graft (TEMG) that occurs in the in vitro technique. In vitro muscle tissue engineering includes the seeding of cells onto a biomaterial scaffold, but goes a step further by adding growth factors and biochemical and biophysical cues to promote cell growth, proliferation, differentiation, and finally regeneration into a functional muscle tissue construct. Typically, in vitro scaffolds contain specific surface features which guide the direction of cell proliferation. They are usually fibrous with aligned pores as these features encourage cell adhesion during regeneration. Beyond the types of scaffolds used in this technique, a largely important aspect of this technique is the electrical and mechanical stimulation which mimic the natural regeneration environment and encourage the expansion of intracellular communication pathways. Before TEMGs are introduced into the wound defect, they musts be vascularized to promote proper integration with the host tissue. To achieve vascularization, researchers typically seed a scaffold with multiple cell types in order to develop both muscle tissue and vascular pathways. This process prevents rejection of the TEMG upon implantation as it is able to effectively thrive in the host tissue environment. There is always a risk of immune rejection when implanting fully developed tissue, though, so this method tissue regeneration is the most closely monitored post-implantation.
The in vitro muscle tissue engineering technique is used to create muscle tissue with more successful functional and mechanical properties. According to Carnes & Pins in Skeletal Muscle Tissue Engineering: Biomaterials-Based Strategies for the Treatment of Volumetric Muscle Loss, this approach develops a microenvironment that is more conducive to enhancing tissue regeneration upon implantation, thus restoring full functionality to patients. | 2 | Tissue Engineering |
Bioremediation utilizes microorganisms or in recent times, materials of biological origin, such as enzymes, biocomposites, biopolymers, or nanoparticles, to biochemically degrade contaminants into harmless substances, making it an environmentally friendly and cost-effective alternative; 3D bioprinting facilitates the fabrication of functional structures utilizing these materials that enhance bioremediation processes leading to a significant interest in the application of 3D bioprinted constructs in improving bioremediation. | 2 | Tissue Engineering |
In Australia, the average age of women undergoing ART treatment is 35.5 years among those using their own eggs (one in four being 40 or older) and 40.5 years among those using donated eggs. While IVF is available in Australia, Australians using IVF are unable to choose their baby's gender. | 1 | Cryobiology |
* [http://dspace.mit.edu/handle/1721.1/50230 MIT Open Access Articles].
* (manuscript).
* In the foreword by the president of ENEA the belief is expressed that the cold fusion phenomenon is proved. | 3 | Nuclear Fusion |
When ferrimagnets are exposed to an external magnetic field, they display what is called magnetic hysteresis, where magnetic behavior depends on the history of the magnet. They also exhibit a saturation magnetization ; this magnetization is reached when the external field is strong enough to make all the moments align in the same direction. When this point is reached, the magnetization cannot increase, as there are no more moments to align. When the external field is removed, the magnetization of the ferrimagnet does not disappear, but a nonzero magnetization remains. This effect is often used in applications of magnets. If an external field in the opposite direction is applied subsequently, the magnet will demagnetize further until it eventually reaches a magnetization of . This behavior results in what is called a hysteresis loop. | 7 | Magnetic Ordering |
Dip pen nanolithography (DPN) is a scanning probe lithography technique where an atomic force microscope (AFM) tip is used to create patterns directly on a range of substances with a variety of inks. A common example of this technique is exemplified by the use of alkane thiolates to imprint onto a gold surface. This technique allows surface patterning on scales of under 100 nanometers. DPN is the nanotechnology analog of the dip pen (also called the quill pen), where the tip of an atomic force microscope cantilever acts as a "pen", which is coated with a chemical compound or mixture acting as an "ink", and put in contact with a substrate, the "paper".
DPN enables direct deposition of nanoscale materials onto a substrate in a flexible manner. Recent advances have demonstrated massively parallel patterning using two-dimensional arrays of 55,000 tips.
Applications of this technology currently range through chemistry, materials science, and the life sciences, and include such work as ultra high density biological nanoarrays, and additive photomask repair. | 2 | Tissue Engineering |
Lung hysteresis is evident when observing the compliance of a lung on inspiration versus expiration. The difference in compliance (Δvolume/Δpressure) is due to the additional energy required to overcome surface tension forces during inspiration to recruit and inflate additional alveoli.
The transpulmonary pressure vs Volume curve of inhalation is different from the Pressure vs Volume curve of exhalation, the difference being described as hysteresis. Lung volume at any given pressure during inhalation is less than the lung volume at any given pressure during exhalation. | 7 | Magnetic Ordering |
Glycogen synthase (UDP-glucose-glycogen glucosyltransferase) is a key enzyme in glycogenesis, the conversion of glucose into glycogen. It is a glycosyltransferase () that catalyses the reaction of UDP-glucose and (1,4---glucosyl) to yield UDP and (1,4---glucosyl). | 6 | Carbohydrates |
According to IUPAC nomenclature of organic chemistry, the hydronium ion should be referred to as oxonium. Hydroxonium may also be used unambiguously to identify it.
An oxonium ion is any cation containing a trivalent oxygen atom. | 4 | Acids + Bases |
The first successful man-made fusion device was the boosted fission weapon tested in 1951 in the Greenhouse Item test. The first true fusion weapon was 1952s Ivy Mike, and the first practical example was 1954s Castle Bravo. In these devices, the energy released by a fission explosion compresses and heats the fuel, starting a fusion reaction. Fusion releases neutrons. These neutrons hit the surrounding fission fuel, causing the atoms to split apart much faster than normal fission processes. This increased the effectiveness of bombs: normal fission weapons blow themselves apart before all their fuel is used; fusion/fission weapons do not waste their fuel. | 3 | Nuclear Fusion |
Select filter cloth to obtain a good surface for cake formation. Use twill weave variation in the construction pattern of the fabric for better wear resistance. The belt tension, de-mooning bar height, wash water quantity and discharge roll speed are carefully tuned to maintain a good path for the cake formation to prevent excessive wear of the filter cloth. | 5 | Separation Processes |
Although the experimental protocol had not been published, physicists in several countries attempted, and failed, to replicate the excess heat phenomenon. The first paper submitted to Nature reproducing excess heat, although it passed peer review, was rejected because most similar experiments were negative and there were no theories that could explain a positive result; this paper was later accepted for publication by the journal Fusion Technology. Nathan Lewis, professor of chemistry at the California Institute of Technology, led one of the most ambitious validation efforts, trying many variations on the experiment without success, while CERN physicist Douglas R. O. Morrison said that "essentially all" attempts in Western Europe had failed. Even those reporting success had difficulty reproducing Fleischmann and Pons' results. On 10 April 1989, a group at Texas A&M University published results of excess heat and later that day a group at the Georgia Institute of Technology announced neutron production—the strongest replication announced up to that point due to the detection of neutrons and the reputation of the lab. On 12 April Pons was acclaimed at an ACS meeting. But Georgia Tech retracted their announcement on 13 April, explaining that their neutron detectors gave false positives when exposed to heat. Another attempt at independent replication, headed by Robert Huggins at Stanford University, which also reported early success with a light water control, became the only scientific support for cold fusion in 26 April US Congress hearings. But when he finally presented his results he reported an excess heat of only one degree Celsius, a result that could be explained by chemical differences between heavy and light water in the presence of lithium. He had not tried to measure any radiation and his research was derided by scientists who saw it later. For the next six weeks, competing claims, counterclaims, and suggested explanations kept what was referred to as "cold fusion" or "fusion confusion" in the news.
In April 1989, Fleischmann and Pons published a "preliminary note" in the Journal of Electroanalytical Chemistry. This paper notably showed a gamma peak without its corresponding Compton edge, which indicated they had made a mistake in claiming evidence of fusion byproducts. Fleischmann and Pons replied to this critique, but the only thing left clear was that no gamma ray had been registered and that Fleischmann refused to recognize any mistakes in the data. A much longer paper published a year later went into details of calorimetry but did not include any nuclear measurements.
Nevertheless, Fleischmann and Pons and a number of other researchers who found positive results remained convinced of their findings. The University of Utah asked Congress to provide $25 million to pursue the research, and Pons was scheduled to meet with representatives of President Bush in early May.
On 30 April 1989, cold fusion was declared dead by The New York Times. The Times called it a circus the same day, and the Boston Herald attacked cold fusion the following day.
On 1 May 1989, the American Physical Society held a session on cold fusion in Baltimore, including many reports of experiments that failed to produce evidence of cold fusion. At the end of the session, eight of the nine leading speakers stated that they considered the initial Fleischmann and Pons claim dead, with the ninth, Johann Rafelski, abstaining. Steven E. Koonin of Caltech called the Utah report a result of "the incompetence and delusion of Pons and Fleischmann," which was met with a standing ovation. Douglas R. O. Morrison, a physicist representing CERN, was the first to call the episode an example of pathological science.
On 4 May, due to all this new criticism, the meetings with various representatives from Washington were cancelled.
From 8 May, only the A&M tritium results kept cold fusion afloat.
In July and November 1989, Nature published papers critical of cold fusion claims. Negative results were also published in several other scientific journals including Science, Physical Review Letters, and Physical Review C (nuclear physics).
In August 1989, in spite of this trend, the state of Utah invested $4.5 million to create the National Cold Fusion Institute.
The United States Department of Energy organized a special panel to review cold fusion theory and research. The panel issued its report in November 1989, concluding that results as of that date did not present convincing evidence that useful sources of energy would result from the phenomena attributed to cold fusion. The panel noted the large number of failures to replicate excess heat and the greater inconsistency of reports of nuclear reaction byproducts expected by established conjecture. Nuclear fusion of the type postulated would be inconsistent with current understanding and, if verified, would require established conjecture, perhaps even theory itself, to be extended in an unexpected way. The panel was against special funding for cold fusion research, but supported modest funding of "focused experiments within the general funding system". Cold fusion supporters continued to argue that the evidence for excess heat was strong, and in September 1990 the National Cold Fusion Institute listed 92 groups of researchers from 10 countries that had reported corroborating evidence of excess heat, but they refused to provide any evidence of their own arguing that it could endanger their patents. However, no further DOE nor NSF funding resulted from the panel's recommendation. By this point, however, academic consensus had moved decidedly toward labeling cold fusion as a kind of "pathological science".
In March 1990, Michael H. Salamon, a physicist from the University of Utah, and nine co-authors reported negative results. University faculty were then "stunned" when a lawyer representing Pons and Fleischmann demanded the Salamon paper be retracted under threat of a lawsuit. The lawyer later apologized; Fleischmann defended the threat as a legitimate reaction to alleged bias displayed by cold-fusion critics.
In early May 1990, one of the two A&M researchers, Kevin Wolf, acknowledged the possibility of spiking, but said that the most likely explanation was tritium contamination in the palladium electrodes or simply contamination due to sloppy work. In June 1990 an article in Science by science writer Gary Taubes destroyed the public credibility of the A&M tritium results when it accused its group leader John Bockris and one of his graduate students of spiking the cells with tritium. In October 1990 Wolf finally said that the results were explained by tritium contamination in the rods. An A&M cold fusion review panel found that the tritium evidence was not convincing and that, while they couldn't rule out spiking, contamination and measurements problems were more likely explanations, and Bockris never got support from his faculty to resume his research.
On 30 June 1991, the National Cold Fusion Institute closed after it ran out of funds; it found no excess heat, and its reports of tritium production were met with indifference.
On 1 January 1991, Pons left the University of Utah and went to Europe. In 1992, Pons and Fleischmann resumed research with Toyota Motor Corporation's IMRA lab in France. Fleischmann left for England in 1995, and the contract with Pons was not renewed in 1998 after spending $40 million with no tangible results. The IMRA laboratory stopped cold fusion research in 1998 after spending £12 million. Pons has made no public declarations since, and only Fleischmann continued giving talks and publishing papers.
Mostly in the 1990s, several books were published that were critical of cold fusion research methods and the conduct of cold fusion researchers. Over the years, several books have appeared that defended them. Around 1998, the University of Utah had already dropped its research after spending over $1 million, and in the summer of 1997, Japan cut off research and closed its own lab after spending $20 million. | 3 | Nuclear Fusion |
Formerly the name "carbohydrate" was used in chemistry for any compound with the formula C (HO). Following this definition, some chemists considered formaldehyde (CHO) to be the simplest carbohydrate, while others claimed that title for glycolaldehyde. Today, the term is generally understood in the biochemistry sense, which excludes compounds with only one or two carbons and includes many biological carbohydrates which deviate from this formula. For example, while the above representative formulas would seem to capture the commonly known carbohydrates, ubiquitous and abundant carbohydrates often deviate from this. For example, carbohydrates often display chemical groups such as: N-acetyl (e.g. chitin), sulfate (e.g. glycosaminoglycans), carboxylic acid and deoxy modifications (e.g. fucose and sialic acid).
Natural saccharides are generally built of simple carbohydrates called monosaccharides with general formula (CHO) where n is three or more. A typical monosaccharide has the structure H–(CHOH)(C=O)–(CHOH)–H, that is, an aldehyde or ketone with many hydroxyl groups added, usually one on each carbon atom that is not part of the aldehyde or ketone functional group. Examples of monosaccharides are glucose, fructose, and glyceraldehydes. However, some biological substances commonly called "monosaccharides" do not conform to this formula (e.g. uronic acids and deoxy-sugars such as fucose) and there are many chemicals that do conform to this formula but are not considered to be monosaccharides (e.g. formaldehyde CHO and inositol (CHO)).
The open-chain form of a monosaccharide often coexists with a closed ring form where the aldehyde/ketone carbonyl group carbon (C=O) and hydroxyl group (–OH) react forming a hemiacetal with a new C–O–C bridge.
Monosaccharides can be linked together into what are called polysaccharides (or oligosaccharides) in a large variety of ways. Many carbohydrates contain one or more modified monosaccharide units that have had one or more groups replaced or removed. For example, deoxyribose, a component of DNA, is a modified version of ribose; chitin is composed of repeating units of N-acetyl glucosamine, a nitrogen-containing form of glucose. | 6 | Carbohydrates |
Cold fusion is a hypothesized type of nuclear reaction that would occur at, or near, room temperature. It would contrast starkly with the "hot" fusion that is known to take place naturally within stars and artificially in hydrogen bombs and prototype fusion reactors under immense pressure and at temperatures of millions of degrees, and be distinguished from muon-catalyzed fusion. There is currently no accepted theoretical model that would allow cold fusion to occur.
In 1989, two electrochemists, Martin Fleischmann and Stanley Pons, reported that their apparatus had produced anomalous heat ("excess heat") of a magnitude they asserted would defy explanation except in terms of nuclear processes. They further reported measuring small amounts of nuclear reaction byproducts, including neutrons and tritium. The small tabletop experiment involved electrolysis of heavy water on the surface of a palladium (Pd) electrode. The reported results received wide media attention and raised hopes of a cheap and abundant source of energy.
Many scientists tried to replicate the experiment with the few details available. Hopes faded with the large number of negative replications, the withdrawal of many reported positive replications, the discovery of flaws and sources of experimental error in the original experiment, and finally the discovery that Fleischmann and Pons had not actually detected nuclear reaction byproducts. By late 1989, most scientists considered cold fusion claims dead, and cold fusion subsequently gained a reputation as pathological science. In 1989 the United States Department of Energy (DOE) concluded that the reported results of excess heat did not present convincing evidence of a useful source of energy and decided against allocating funding specifically for cold fusion. A second DOE review in 2004, which looked at new research, reached similar conclusions and did not result in DOE funding of cold fusion. Presently, since articles about cold fusion are rarely published in peer-reviewed mainstream scientific journals, they do not attract the level of scrutiny expected for mainstream scientific publications.
Nevertheless, some interest in cold fusion has continued through the decades—for example, a Google-funded failed replication attempt was published in a 2019 issue of Nature. A small community of researchers continues to investigate it, often under the alternative designations low-energy nuclear reactions (LENR) or condensed matter nuclear science (CMNS). | 3 | Nuclear Fusion |
Timex introduced the Indiglo technology in 1992 in their Ironman watch line and subsequently expanded its use to 70% of their watch line, including mens and womens watches, sport watches and chronographs. Casio introduced their version of electroluminescent backlight technology in 1995.
The Indiglo name was later licensed to other companies, such as Austin Innovations Inc., for use on their electroluminescent products.
From 2006-2011, the Timex Group marketed a line of high-end quartz watches under the TX Watch Company brand, using a proprietary six-hand, four-motor, micro-processor controlled movement. To separate the brand from Timex, the movements had luxury features associated with a higher-end brand, e.g., sapphire crystals and stainless steel or titanium casework — and used hands treated with super-luminova luminescent pigment for low-light legibility — rather than indiglo technology.
When the Timex Group migrated the microprocessor-controlled, multi-motor, multi-hand technology to its Timex brand in 2012, it created a sub-collection marketed as Intelligent Quartz (IQ). The line employed the same movements and capabilities from the TX brand, at a much lower price-point -- incorporating indiglo technology rather than the super-luminova pigments. | 0 | Luminescence |
* Intracytoplasmic sperm injection (ICSI) is where a single sperm is injected directly into an egg. Its main usage as an expansion of IVF is to overcome male infertility problems, although it may also be used where eggs cannot easily be penetrated by sperm, and occasionally in conjunction with sperm donation. It can be used in teratozoospermia, since once the egg is fertilised abnormal sperm morphology does not appear to influence blastocyst development or blastocyst morphology.
* Additional methods of embryo profiling. For example, methods are emerging in making comprehensive analyses of up to entire genomes, transcriptomes, proteomes and metabolomes which may be used to score embryos by comparing the patterns with ones that have previously been found among embryos in successful versus unsuccessful pregnancies.
* Assisted zona hatching (AZH) can be performed shortly before the embryo is transferred to the uterus. A small opening is made in the outer layer surrounding the egg in order to help the embryo hatch out and aid in the implantation process of the growing embryo.
* In egg donation and embryo donation, the resultant embryo after fertilisation is inserted in another person than the one providing the eggs. These are resources for those with no eggs due to surgery, chemotherapy, or genetic causes; or with poor egg quality, previously unsuccessful IVF cycles or advanced maternal age. In the egg donor process, eggs are retrieved from a donors ovaries, fertilised in the laboratory with sperm, and the resulting healthy embryos are returned to the recipients uterus.
* In oocyte selection, the oocytes with optimal chances of live birth can be chosen. It can also be used as a means of preimplantation genetic screening.
* Embryo splitting can be used for twinning to increase the number of available embryos.
*Cytoplasmic transfer is where the cytoplasm from a donor egg is injected into an egg with compromised mitochondria. The resulting egg is then fertilised with sperm and introduced into a uterus, usually that of the person who provided the recipient egg and nuclear DNA. Cytoplasmic transfer was created to aid those who experience infertility due to deficient or damaged mitochondria, contained within an egg's cytoplasm. | 1 | Cryobiology |
Isopropyl β--1-thiogalactopyranoside (IPTG) is a molecular biology reagent. This compound is a molecular mimic of allolactose, a lactose metabolite that triggers transcription of the lac operon, and it is therefore used to induce protein expression where the gene is under the control of the lac operator. | 6 | Carbohydrates |
Vogel was a proponent of research into plant consciousness and believed "empathy between plant and human" could be established. | 0 | Luminescence |
The word neo-organ comes from the Greek word "neos," which means new. Organ transplants have been successfully used for medical purposes since 1954. The difficulty with the traditional process of organ transplants is that it requires waiting for a viable donor to donate an organ. The process of matching the organ to make sure it is compatible with the patient has also proven to be challenging. There are two main challenges: finding the right candidate for the patient and avoiding the patient rejecting the organ even if it is a match. Neo-organs can be used to avoid the process of organ matching and donating. | 2 | Tissue Engineering |
In certain countries, including Austria, Italy, Estonia, Hungary, Spain and Israel, the male does not have the full ability to withdraw consent to storage or use of embryos once they are fertilised. In the United States, the matter has been left to the courts on a more or less ad hoc basis. If embryos are implanted and a child is born contrary to the wishes of the male, he still has legal and financial responsibilities of a father. | 1 | Cryobiology |
When the periodicity of the magnetic order coincides with the periodicity of crystallographic order, the magnetic phase is said to be commensurate, and can be well-described by a magnetic space group. However, when this is not the case, the order does not correspond to any magnetic space group. These phases can instead be described by magnetic superspace groups, which describe incommensurate order. This is the same formalism often used to describe the ordering of some quasicrystals. | 7 | Magnetic Ordering |
In South Asia, acid attacks have been used as a form of revenge for refusal of sexual advances, proposals of marriage and demands for dowry. Scholars Taru Bahl and M.H. Syed say that land and property disputes are another leading cause. | 4 | Acids + Bases |
Unlike single-bubble sonoluminescence, multi-bubble sonoluminescence is the creation of many oscillating and collapsing bubbles. Typically in MBSL, the light emission from each individual bubble is weaker than in SBSL because the neighboring bubbles can interact and affect each other. Because each neighboring bubble can interact with each other, it can make it more difficult to produce accurate studies and to characterize the properties of the collapsing bubble. | 0 | Luminescence |
The declassification of the program was a large topic of discussion between scientists at all of the laboratories involved with the project and at the Sherwood conferences. The reasoning for an initial high classification status was that if the research into controlled fusion were to be successful then it would be a significant advantage in regards to military aspects. In particular, fusion products high-energy neutrons which could be used to enrich uranium into plutonium for nuclear bomb production. If a small fusion machine was possible, this represented a significant proliferation risk.
However, as the difficultly in making a working fusion reactor became increasingly clear, fears of hidden reactors faded. Additionally, while some of the required industrial work could be conducted without access to the classified information, there were some instances where the classified information of the program was a necessity for those people working on projects such as the large-scale stellarator, the ultra-high vacuum, and the problem of energy storage. In these instances, there was a contract with the Commission that the information that was being used would only be shared with the personnel that was directly working on the project. It soon became apparent that industrial companies were expected to become highly invested in the area of fission and because of this it became clear that these companies should have full access to the research information obtained by Project Sherwood. In June 1956, permits for the research information from Project Sherwood became available through the Commission for companies that were qualified.
Between 1955 and 1958, information became more and more available to the public with its gradual declassification beginning with the sharing of information with the United Kingdom. Huge supporters of declassification of the program included the director of the Division of Research, Thomas Johnson, and a member of his staff, Amasa Bishop. Some of their reasoning for wanting declassification was that the secrecy of the project could negatively impact their ability to enlist and employ experienced personnel to the program. The also argued that it would change the way their conferences could be held. The scientists working on the project would be able to freely discuss their findings with others in the scientific community rather than only the scientists working on the same project.
In 1956, Soviet physicist Igor Kurchatov gave a talk in the UK where he revealed the entire Soviet fusion program and detailed the problems they were having. Now that the very group of people the classification was intended to keep in the dark were at roughly the same stage of development, there was no obvious reason to continue classification. While the UK had been among the first to classify their program in the aftermath of the Klaus Fuchs affair in 1950, in the summer of 1957 they appeared to have successfully created fusion in their new ZETA and were clamoring to tell the press of their advances. Their agreement to share information with the US required them to classify their work, and now they also began pressing the US to agree to declassification.
By May 1958, basic information about the various projects within Project Sherwood including the stellarator, magnetic mirrors, and molecular ion beams had been released to the public. | 3 | Nuclear Fusion |
Dye-sub printing is a digital printing technology using full color artwork that works with polyester and polymer-coated substrates. Also referred to as digital sublimation, the process is commonly used for decorating apparel, signs and banners, as well as novelty items such as cell phone covers, plaques, coffee mugs, and other items with sublimation-friendly surfaces. The process uses the science of sublimation, in which heat and pressure are applied to a solid, turning it into a gas through an endothermic reaction without passing through the liquid phase.
In sublimation printing, unique sublimation dyes are transferred to sheets of “transfer” paper via liquid gel ink through a piezoelectric print head. The ink is deposited on these high-release inkjet papers, which are used for the next step of the sublimation printing process. After the digital design is printed onto sublimation transfer sheets, it is placed on a heat press along with the substrate to be sublimated.
In order to transfer the image from the paper to the substrate, it requires a heat press process that is a combination of time, temperature and pressure. The heat press applies this special combination, which can change depending on the substrate, to “transfer” the sublimation dyes at the molecular level into the substrate. The most common dyes used for sublimation activate at 350 degrees Fahrenheit. However, a range of 380 to 420 degrees Fahrenheit is normally recommended for optimal color.
The result of the sublimation process is a nearly permanent, high resolution, full color print. Because the dyes are infused into the substrate at the molecular level, rather than applied at a topical level (such as with screen printing and direct to garment printing), the prints will not crack, fade or peel from the substrate under normal conditions. | 5 | Separation Processes |
Internally, ferromagnetic materials have a structure that is divided into domains, each of which is a region of uniform magnetization. When a magnetic field is applied, the boundaries between the domains shift and the domains rotate; both of these effects cause a change in the materials dimensions. The reason that a change in the magnetic domains of a material results in a change in the materials dimensions is a consequence of magnetocrystalline anisotropy; it takes more energy to magnetize a crystalline material in one direction than in another. If a magnetic field is applied to the material at an angle to an easy axis of magnetization, the material will tend to rearrange its structure so that an easy axis is aligned with the field to minimize the free energy of the system. Since different crystal directions are associated with different lengths, this effect induces a strain in the material.
The reciprocal effect, the change of the magnetic susceptibility (response to an applied field) of a material when subjected to a mechanical stress, is called the Villari effect. Two other effects are related to magnetostriction: the Matteucci effect is the creation of a helical anisotropy of the susceptibility of a magnetostrictive material when subjected to a torque and the Wiedemann effect is the twisting of these materials when a helical magnetic field is applied to them.
The Villari reversal is the change in sign of the magnetostriction of iron from positive to negative when exposed to magnetic fields of approximately 40 kA/m.
On magnetization, a magnetic material undergoes changes in volume which are small: of the order 10. | 7 | Magnetic Ordering |
Histidine-tryptophan-ketoglutarate, or Custodiol HTK solution, is a high-flow, low-potassium preservation solution used for organ transplantation. The solution was initially developed by Hans-Jürgen Bretschneider.
HTK solution is intended for perfusion and flushing of donor liver, kidney, heart, lung and pancreas prior to removal from the donor and for preserving these organs during hypothermic storage and transport to the recipient. HTK solution is based on the principle of inactivating organ function by withdrawal of extracellular sodium and calcium, together with intensive buffering of the extracellular space by means of histidine/histidine hydrochloride, so as to prolong the period during which the organs will tolerate interruption of oxygenated blood. The composition of HTK is similar to that of intracellular fluid. All of the components of HTK occur naturally in the body. The osmolarity of HTK is 310 mOsm/L. | 1 | Cryobiology |
Hydroiodic acid reacts with oxygen in air to give iodine:
:4 HI + O → 2 + 2 I
Like other hydrogen halides, hydroiodic acid adds to alkenes to give alkyl iodides. It can also be used as a reducing agent, for example in the reduction of aromatic nitro compounds to anilines. | 4 | Acids + Bases |
Solar neutrinos are produced in the core of the Sun through various nuclear fusion reactions, each of which occurs at a particular rate and leads to its own spectrum of neutrino energies. Details of the more prominent of these reactions are described below.
The main contribution comes from the proton–proton chain. The reaction is:
or in words:
: two protons deuteron + positron + electron neutrino.
Of all Solar neutrinos, approximately 91% are produced from this reaction. As shown in the figure titled "Solar neutrinos (proton–proton chain) in the standard solar model", the deuteron will fuse with another proton to create a He nucleus and a gamma ray. This reaction can be seen as:
The isotope He can be produced by using the He in the previous reaction which is seen below.
With both helium-3 and helium-4 now in the environment, one of each weight of helium nucleus can fuse to produce beryllium:
Beryllium-7 can follow two different paths from this stage: It could capture an electron and produce the more stable lithium-7 nucleus and an electron neutrino, or alternatively, it could capture one of the abundant protons, which would create boron-8. The first reaction via lithium-7 is:
This lithium-yielding reaction produces approximately 7% of the solar neutrinos. The resulting lithium-7 later combines with a proton to produce two nuclei of helium-4. The alternative reaction is proton capture, that produces boron-8, which then beta decays into beryllium-8 as shown below:
This alternative boron-yielding reaction produces about 0.02% of the solar neutrinos; although so few that they would conventionally be neglected, these rare solar neutrinos stand out because of their higher average energies. The asterisk (*) on the beryllium-8 nucleus indicates that it is in an excited, unstable state. The excited beryllium-8 nucleus then splits into two helium-4 nuclei: | 3 | Nuclear Fusion |
** Building construction for the immense 192-beam 500-terawatt NIF project is completed and construction of laser beam-lines and target bay diagnostics commences, expecting to take its first full system shot in 2010.
** Negotiations on the Joint Implementation of ITER begin between Canada, countries represented by the European Union, Japan and Russia.
** Claims and counter-claims are published regarding bubble fusion, in which a table-top apparatus was reported as producing small-scale fusion in a liquid undergoing acoustic cavitation. Like cold fusion (see 1989), it is later dismissed.
** European Union proposes Cadarache in France and Vandellos in Spain as candidate sites for ITER while Japan proposes Rokkasho.
** The United States rejoins the ITER project with China and Republic of Korea also joining. Canada withdraws.
** Cadarache in France is selected as the European Candidate Site for ITER.
** Sandia National Laboratories begins fusion experiments in the Z machine.
** The United States drops its own ITER-scale tokamak project, FIRE, recognising an inability to match EU progress.
** Following final negotiations between the EU and Japan, ITER chooses Cadarache over Rokkasho for the site of the reactor. In concession, Japan is able to host the related materials research facility and granted rights to fill 20% of the project's research posts while providing 10% of the funding.
** The NIF fires its first bundle of eight beams achieving the highest ever energy laser pulse of 152.8 kJ (infrared).
** China's EAST test reactor is completed, the first tokamak experiment to use superconducting magnets to generate both the toroidal and poloidal fields.
** Construction of the NIF reported as complete.
** Ricardo Betti, the third Under Secretary, responsible for Nuclear Energy, testifies before Congress: "IFE [ICF for energy production] has no home". | 3 | Nuclear Fusion |
Gastrointestinal organoids refer to organoids that recapitulate structures of the gastrointestinal tract. The gastrointestinal tract arises from the endoderm, which during development forms a tube that can be divided in three distinct regions, which give rise to, along with other organs, the following sections of the gastrointestinal tract:
:# The foregut gives rise to the oral cavity and the stomach
:# The midgut gives rise to the small intestines and the ascending colon
:# The hindgut gives rise to the rectum and the rest of the colon
Organoids have been created for the following structures of the gastrointestinal tract: | 2 | Tissue Engineering |
Some research groups initially reported that they had replicated the Fleischmann and Pons results but later retracted their reports and offered an alternative explanation for their original positive results. A group at Georgia Tech found problems with their neutron detector, and Texas A&M discovered bad wiring in their thermometers. These retractions, combined with negative results from some famous laboratories, led most scientists to conclude, as early as 1989, that no positive result should be attributed to cold fusion. | 3 | Nuclear Fusion |
He is the author of numerous books including Foundations of Solid Mechanics, Continuum Mechanics, and a series of books on Biomechanics. He is also one of the principal founders of the Journal of Biomechanics and was a past chair of the ASME International Applied Mechanics Division. In 1972, Fung established the Biomechanics Symposium under the American Society of Mechanical Engineers. This biannual summer meeting, first held at the Georgia Institute of Technology, became the annual Summer Bioengineering Conference. Fung and colleagues were also the first to recognize the importance of residual stress on arterial mechanical behavior. | 2 | Tissue Engineering |
Many UVGI systems use UV wavelengths that can be harmful to humans, resulting in both immediate and long-term effects. Acute impacts on the eyes and skin can include conditions such as photokeratitis (often termed "snow blindness") and erythema (reddening of the skin), while chronic exposure may heighten the risk of skin cancer.
However, the safety and effects of UV vary extensively by wavelength, implying that not all UVGI systems pose the same level of hazards. Humans typically encounter UV light in the form of solar UV, which comprises significant portions of UV-A and UV-B, but excludes UV-C. The UV-B band, able to penetrate deep into living, replicating tissue, is recognized as the most damaging and carcinogenic.
Many standard UVGI systems, such as low-pressure mercury (LP-Hg) lamps, produce broad-band emissions in the UV-C range and also peaks in the UV-B band. This often makes it challenging to attribute damaging effects to a specific wavelength. Nevertheless, longer wavelengths in the UV-C band can cause conditions like photokeratitis and erythema. Hence, many UVGI systems are used in settings where direct human exposure is limited, such as with upper-room UVGI air cleaners and water disinfection systems.
Precautions are commonly implemented to protect users of these UVGI systems, including:
* Warning labels: Labels alert users to the dangers of UV light.
* Interlocking systems: Shielded systems, such as closed water tanks or air circulation units, often have interlocks that automatically shut off the UV lamps if the system is opened for human access. Clear viewports that block UV-C are also available.
* Personal protective equipment: Most protective eyewear, particularly those compliant with ANSI Z87.1, block UV-C. Similarly, clothing, plastics, and most types of glass (excluding fused silica) effectively impede UV-C.
Since the early 2010s there has been growing interest in the far-UVC wavelengths of 200-235 nm for whole-room exposure. These wavelengths are generally considered safer due to their limited penetration depth caused by increased protein absorption. This feature confines far-UVC exposure to the superficial layers of tissue, such as the outer layer of dead skin (the stratum corneum) and the tear film and surface cells of the cornea. As these tissues do not contain replicating cells, damage to them poses less carcinogenic risk. It has also been demonstrated that far-UVC does not cause erythema or damage to the cornea at levels many times that of solar UV or conventional 254 nm UVGI systems. | 8 | Ultraviolet Radiation |
Like flux density, the magnetostriction also exhibits hysteresis versus the strength of the magnetizing field. The shape of this hysteresis loop (called "dragonfly loop") can be reproduced using the Jiles-Atherton model. | 7 | Magnetic Ordering |
This methods consists in selecting the cell type of interest, usually with antibiotic resistance. For this purpose, the source material cells are modified to contain antibiotic resistance cassette under a target cell type specific promoter. Only cells committed to the lineage of interest is surviving the selection. | 2 | Tissue Engineering |
* The rotary vacuum drum filter is a continuous and automatic operation, so the operating cost is low.
* The variation of the drum speed rotating can be used to control the cake thickness.
* The process can be easily modified (pre-coating filter process).
* Can produce relatively clean product by adding a showering device. | 5 | Separation Processes |
Fluorophores have particular importance in the field of biochemistry and protein studies, for example, in immunofluorescence, cell analysis, immunohistochemistry, and small molecule sensors. | 0 | Luminescence |
O-GlcNAc (short for O-linked GlcNAc or O-linked β-N-acetylglucosamine) is a reversible enzymatic post-translational modification that is found on serine and threonine residues of nucleocytoplasmic proteins. The modification is characterized by a β-glycosidic bond between the hydroxyl group of serine or threonine side chains and N-acetylglucosamine (GlcNAc). O-GlcNAc differs from other forms of protein glycosylation: (i) O-GlcNAc is not elongated or modified to form more complex glycan structures, (ii) O-GlcNAc is almost exclusively found on nuclear and cytoplasmic proteins rather than membrane proteins and secretory proteins, and (iii) O-GlcNAc is a highly dynamic modification that turns over more rapidly than the proteins which it modifies. O-GlcNAc is conserved across metazoans.
Due to the dynamic nature of O-GlcNAc and its presence on serine and threonine residues, O-GlcNAcylation is similar to protein phosphorylation in some respects. While there are roughly 500 kinases and 150 phosphatases that regulate protein phosphorylation in humans, there are only 2 enzymes that regulate the cycling of O-GlcNAc: O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) catalyze the addition and removal of O-GlcNAc, respectively. OGT utilizes UDP-GlcNAc as the donor sugar for sugar transfer.
First reported in 1984, this post-translational modification has since been identified on over 5,000 proteins. Numerous functional roles for O-GlcNAcylation have been reported including crosstalking with serine/threonine phosphorylation, regulating protein-protein interactions, altering protein structure or enzyme activity, changing protein subcellular localization, and modulating protein stability and degradation. Numerous components of the cells transcription machinery have been identified as being modified by O-GlcNAc, and many studies have reported links between O-GlcNAc, transcription, and epigenetics. Many other cellular processes are influenced by O-GlcNAc such as apoptosis, the cell cycle, and stress responses. As UDP-GlcNAc is the final product of the hexosamine biosynthetic pathway, which integrates amino acid, carbohydrate, fatty acid, and nucleotide metabolism, it has been suggested that O-GlcNAc acts as a "nutrient sensor" and responds to the cells metabolic status. Dysregulation of O-GlcNAc has been implicated in many pathologies including Alzheimer's disease, cancer, diabetes, and neurodegenerative disorders. | 6 | Carbohydrates |
Photobiology is the scientific study of the beneficial and harmful interactions of non-ionizing radiation in living organisms, conventionally demarcated around 10 eV, the first ionization energy of oxygen. UV ranges roughly from 3 to 30 eV in energy. Hence photobiology entertains some, but not all, of the UV spectrum. | 8 | Ultraviolet Radiation |
A formation light, also known as a slime light, is a type of thin film electroluminescent light that assists aircraft flying in formation in low visibility environments. | 0 | Luminescence |
Due to the very low temperatures required, varying levels of stress are put on the DNA samples. Spermatozoa, in particular, are stressed by temperature shock, osmotic stress, and oxidative stress with the latter being the most detrimental. When temperature shock occurs, the membrane is damaged through freezing and thawing of the sperm. Osmotic stress occurs when ice crystals form inside the nucleus during the freezing process, causing differing osmotic pressures within the cell. Oxidative stress is the result of too many reactive oxygen species (ROS), which is highly reactive and damaging to all parts of the cell. Although these stressors are present within the cell, there are solutions to each. By introducing cholesterol to the samples, temperature shock can be reduced. The use of antifreeze proteins provides one solution for osmotic stress. Oxidative stress is the most difficult to combat because of the highly reactive components of ROS, but some measures like adding certain proteins to limit freeze-thaw damage and increase the survival rate of the DNA. | 1 | Cryobiology |
Single-crystal alloys exhibit superior microstrain, but are vulnerable to yielding due to the anisotropic mechanical properties of most metals. It has been observed that for polycrystalline alloys with a high area coverage of preferential grains for microstrain, the mechanical properties (ductility) of magnetostrictive alloys can be significantly improved. Targeted metallurgical processing steps promote abnormal grain growth of {011} grains in galfenol and alfenol thin sheets, which contain two easy axes for magnetic domain alignment during magnetostriction. This can be accomplished by adding particles such as boride species and niobium carbide () during initial chill casting of the ingot.
For a polycrystalline alloy, an established formula for the magnetostriction, λ, from known directional microstrain measurements is:
λ = 1/5(2λ+3λ)
During subsequent hot rolling and recrystallization steps, particle strengthening occurs in which the particles introduce a “pinning” force at grain boundaries that hinders normal (stochastic) grain growth in an annealing step assisted by a atmosphere. Thus, single-crystal-like texture (~90% {011} grain coverage) is attainable, reducing the interference with magnetic domain alignment and increasing microstrain attainable for polycrystalline alloys as measured by semiconducting strain gauges. These surface textures can be visualized using electron backscatter diffraction (EBSD) or related diffraction techniques. | 7 | Magnetic Ordering |
Subsets and Splits