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Most tanning beds are horizontal enclosures with a bench and canopy (lid) that house long, low-pressure fluorescent bulbs (100–200 watt) under an acrylic surface. The tanner is surrounded by bulbs when the canopy is closed. Modern tanning beds emit mostly UVA (the sun emits around 95% UVA and 5% UVB). One review of studies found that the UVB irradiance of beds was on average lower than the summer sun at latitudes 37°S to 35°N, but that UVA irradiance was on average much higher.
The user sets a timer (or it is set remotely by the salon operator), lies on the bed and pulls down the canopy. The maximum exposure time for most low-pressure beds is 15–20 minutes. In the US, maximum times are set by the manufacturer according to how long it takes to produce four "minimal erythema doses" (MEDs), an upper limit laid down by the FDA. An MED is the amount of UV radiation that will produce erythema (redness of the skin) within a few hours of exposure.
High-pressure beds use smaller, higher-wattage quartz bulbs and emit a higher percentage of UVA. They may emit 10–15 times more UVA than the midday sun, and have a shorter maximum exposure time (typically 10–12 minutes). UVA gives an immediate, short-term tan by bronzing melanin in the skin, but no new melanin is formed. UVB has no immediate bronzing effect, but with a delay of 72 hours makes the skin produce new melanin, leading to tans of longer duration. UVA is less likely to cause burning or dry skin than UVB, but is associated with wrinkling and loss of elasticity because it penetrates deeper.
Commercial tanning beds cost $6,000 to $30,000 as of 2006, with high-pressure beds at the high end. One Manhattan chain was charging $10 to $35 per session in 2016, depending on the number, strength, and type of bulbs. This is known as level 1–6 tanning; level 1 involves a basic low-pressure bed with 36 x 100-watt bulbs. Depending on the quality of the bed, it may contain a separate facial tanner, shoulder tanners, a choice of tanning levels and UVA/UVB combinations, sound system, MP3 connection, aromatherapy, air conditioning, a misting option and voice guide. There are also open-air beds, in which the tanner is not entirely enclosed. | 8 | Ultraviolet Radiation |
Radium was discovered by Marie and Pierre Curie in 1898 and was soon combined with paint to make luminescent paint, which was applied to clocks, airplane instruments, and the like, to be able to read them in the dark.
In 1914, Dr. Sabin Arnold von Sochocky and Dr. George S. Willis founded the Radium Luminous Material Corporation. The company made luminescent paint. The company later changed its name to the United States Radium Corporation. The use of radium to provide luminescence for hands and indices on watches soon followed.
The Ingersoll Watch division of the Waterbury Clock Company, a nationally-known maker of low-cost pocket and wristwatches, was a leading popularizer of the use of radium for watch hands and indices through the introduction of their "Radiolite" watches in 1916. The Radiolite series, made in various sizes and models, became a signature of the Connecticut-based company.
Radium dials were typically painted by young women, who used to point their brushes by licking and shaping the bristles prior to painting the fine lines and numbers on the dials. This practice resulted in the ingestion of radium, which caused serious jaw-bone degeneration and malignancy and other dental diseases. The disease, radium-induced osteonecrosis, was recognized as an occupational disease in 1925 after a group of radium painters, known as the Radium Girls, from the United States Radium Corporation sued. By 1930, all dial painters stopped pointing their brushes by mouth. Stopping this practice drastically reduced the amount of radium ingested and therefore, the incidence of malignancy.
Luminous Processes employees interviewed by a journalist in 1978 stated they had been left ignorant of radium's dangers. They were told that eliminating lip-pointing had ended earlier problems. They worked in unvented rooms, they wore smocks that they laundered at home. Geiger counters could pick up readings from pants returned from a dry cleaner and from clothes stored away in a cedar chest." | 0 | Luminescence |
Spiral separators of the wet type, also called spiral concentrators, are devices to separate solid components in a slurry, based upon a combination of the solid particle density as well as the particle's hydrodynamic properties (e.g. drag). The device consists of a tower, around which is wound a sluice, from which slots or channels are placed in the base of the sluice to extract solid particles that have come out of suspension.
As larger and heavier particles sink to the bottom of the sluice faster and experience more drag from the bottom, they travel slower, and so move towards the center of the spiral. Conversely, light particles stay towards the outside of the spiral, with the water, and quickly reach the bottom. At the bottom, a "cut" is made with a set of adjustable bars, channels, or slots, separating the low and high density parts. | 5 | Separation Processes |
The existence of the candoluminescence phenomenon and the underlying mechanism have been the subject of extensive research and debate since the first reports of it in the 1800s. The topic was of particular interest before the introduction of electric lighting, when most artificial light was produced by fuel combustion. The main alternative explanation for candoluminescence is that it is simply "selective" thermal emission in which the material has a very high emissivity in the visible spectrum and a very weak emissivity in the part of the spectrum where the blackbody thermal emission would be highest; in such a system, the emitting material will tend to retain a higher temperature because of the lack of invisible radiative cooling. In this scenario, observations of candoluminescence would simply have been underestimating the temperature of the emitting species. Several authors in the 1950s came to the view that candoluminescence was simply an instance of selective thermal emission, and one of the most prominent researchers in the field, V. A. Sokolov, once advocated eliminating the term from the literature in his noted 1952 review article, only to revise his view several years later. The modern scientific consensus is that candoluminescence does occur, that it is not always simply due to selective thermal emission, but the mechanisms vary depending on the materials involved and the method of heating, particularly the type of flame and the position of the material relative to the flame. | 0 | Luminescence |
Solid chloroauric acid is a hydrophilic (ionic) protic solute. It is soluble in water and other oxygen-containing solvents, such as alcohols, esters, ethers, and ketones. For example, in dry dibutyl ether or diethylene glycol, the solubility exceeds 1 M. Saturated solutions in the organic solvents often are the liquid solvates of specific stoichiometry. Chloroauric acid is a strong monoprotic acid.
When heated in air, solid melts in the water of crystallization, quickly darkens and becomes dark brown. | 4 | Acids + Bases |
Bene Meat Technologies a.s. was founded in 2020 by Mgr. Roman Kříž, who is the project leader. The main biologist of the scientific team is Jiří Janoušek and one of the external scientists involved in the ongoing research is the immunologist Prof. RNDr. Jan Černý, Ph.D. In 2022, the BMT research team consisted of 70 scientists | 2 | Tissue Engineering |
Super-LumiNova granulated pigments are applied either by manual application, screen printing or pad printing. RC Tritech AG recommends up to application thickness in one or multiple layer(s). Over that, the ultraviolet light starts getting problems to effectively reach and activate the bottom of the deposited pigment, diminishing the returns for additional application thickness. The pigments and binders are produced separately, as there is no optimal binder for differing applications. This forces RC Tritech AG to offer many solvent and non-solvent based binder systems to maximally concentrate the granulated pigments in the mixture for application on various surfaces.
Alternatively, RC Tritech AG offers Lumicast pieces, which are highly concentrated luminous Super-LumiNova 3D-castings. According to RC Tritech AG these ceramic parts can be made in any customer desired shape and result in a higher light emission brightness when compared to the common application methods. Lumicast pieces can be glued or form fitted on various surfaces. | 0 | Luminescence |
Tissue opacity is thought to be the result of light scattering due to heterogeneous refractive indices. Tissue clearing methods chemically homogenize refractive indices, resulting in almost completely transparent tissue. | 2 | Tissue Engineering |
In physics, amorphous magnet refers to a magnet made from amorphous solids. Below a certain temperature, these magnets present permanent magnetic phases produced by randomly located magnetic moments. Three common types of amorphous magnetic phases are asperomagnetism, speromagnetism and sperimagnetism, which correspond to ferromagnetism, antiferromagnetism and ferrimagnetism, respectively, of crystalline solids. Spin glass models can present these amorphous types of magnetism. Due to random frustration, amorphous magnets possess many nearly degenerate ground states.
The terms for the amorphous magnetic phases were coined by Michael Coey in 1970s. The Greek root spero/speri () means to scatter. | 7 | Magnetic Ordering |
Most fluorophores are organic small molecules of 20–100 atoms (200–1000 Dalton; the molecular weight may be higher depending on grafted modifications and conjugated molecules), but there are also much larger natural fluorophores that are proteins: green fluorescent protein (GFP) is 27 kDa, and several phycobiliproteins (PE, APC...) are ≈240kDa. As of 2020, the smallest known fluorophore was claimed to be 3-hydroxyisonicotinaldehyde, a compound of 14 atoms and only 123 Da.
Fluorescence particles like quantum dots (2–10 nm diameter, 100–100,000 atoms) are also considered fluorophores.
The size of the fluorophore might sterically hinder the tagged molecule and affect the fluorescence polarity. | 0 | Luminescence |
Insects that are psychrotrophic can survive cold temperatures through several general mechanisms (unlike opportunistic and chill susceptible insects): (1) chill tolerance, (2) freeze avoidance, and (3) freeze tolerance. Chill tolerant insects succumb to freezing temperatures after prolonged exposure to mild or moderate freezing temperatures. Freeze avoiding insects can survive extended periods of time at sub-freezing temperatures in a supercooled state, but die at their supercooling point. Freeze tolerant insects can survive ice crystal formation within their body at sub-freezing temperatures. Freeze tolerance within insects is argued to be on a continuum, with some insect species exhibiting partial (e.g., Tipula paludosa, Hemideina thoracica
), moderate (e.g., Cryptocercus punctulatus), and strong freezing tolerance (e.g., Eurosta solidaginis and Syrphus ribesii), and other insect species exhibiting freezing tolerance with low supercooling point (e.g., Pytho deplanatus). | 1 | Cryobiology |
In control systems, hysteresis can be used to filter signals so that the output reacts less rapidly than it otherwise would by taking recent system history into account. For example, a thermostat controlling a heater may switch the heater on when the temperature drops below A, but not turn it off until the temperature rises above B. (For instance, if one wishes to maintain a temperature of 20 °C then one might set the thermostat to turn the heater on when the temperature drops to below 18 °C and off when the temperature exceeds 22 °C).
Similarly, a pressure switch can be designed to exhibit hysteresis, with pressure set-points substituted for temperature thresholds. | 7 | Magnetic Ordering |
Hydronium is an abundant molecular ion in the interstellar medium and is found in diffuse and dense molecular clouds as well as the plasma tails of comets. Interstellar sources of hydronium observations include the regions of Sagittarius B2, Orion OMC-1, Orion BN–IRc2, Orion KL, and the comet Hale–Bopp.
Interstellar hydronium is formed by a chain of reactions started by the ionization of into by cosmic radiation. can produce either or through dissociative recombination reactions, which occur very quickly even at the low (≥10 K) temperatures of dense clouds. This leads to hydronium playing a very important role in interstellar ion-neutral chemistry.
Astronomers are especially interested in determining the abundance of water in various interstellar climates due to its key role in the cooling of dense molecular gases through radiative processes. However, does not have many favorable transitions for ground-based observations. Although observations of HDO (the deuterated version of water) could potentially be used for estimating abundances, the ratio of HDO to is not known very accurately.
Hydronium, on the other hand, has several transitions that make it a superior candidate for detection and identification in a variety of situations. This information has been used in conjunction with laboratory measurements of the branching ratios of the various dissociative recombination reactions to provide what are believed to be relatively accurate and abundances without requiring direct observation of these species. | 4 | Acids + Bases |
The first sperm banks began as early as 1964 in Iowa, USA and Tokyo, Japan and were established for a medical therapeutic approach to support individuals who were infertile. As a result, over 1 million babies were born within 40 years.
Sperm banks provide the opportunity for individuals to have a child who otherwise would not be able to conceive naturally. This includes, but is not limited to, single women, same-sexed couples, and couples where one partner is infertile.
Where a sperm bank provides fertility services directly to a recipient woman, it may employ different methods of fertilization using donor sperm in order to optimize the chances of a pregnancy. Sperm banks do not provide a cure for infertility in individuals who produce non-viable sperm. Nevertheless, the increasing range of services available through sperm banks enables people to have choices over challenges with reproduction.
Individuals may choose an anonymous donor who will not be a part of family life, or they may choose known donors who may be contacted later in life by the donor children. People may choose to use a surrogate to bear their children, using eggs provided by the person and sperm from a donor. Sperm banks often provide services which enable an individual to have subsequent pregnancies by the same donor, but equally, people may choose to have children by a number of different donors. Sperm banks sometimes enable an individual to choose the sex of their child, enabling even greater control over the way families are planned. Sperm banks increasingly adopt a less formal approach to the provision of their services thereby enabling people to take a relaxed approach to their own individual requirements.
Men who donate semen through a sperm bank provide an opportunity for others who cannot have children on their own. Sperm donors may or may not have legal obligations or responsibilities to the child conceived through this route. Whether a donor is anonymous or not, this factor is important in allowing sperm banks to recruit sperm donors and to use their sperm to produce whatever number of pregnancies from each donor as are permitted where they operate, or alternatively, whatever number they decide.
In many parts of the world sperm banks are not allowed to be established or to operate. Where sperm banks are allowed to operate they are often controlled by local legislation which is primarily intended to protect the unborn child, but which may also provide a compromise between the conflicting views which surround their operation. A particular example of this is the control which is often placed on the number of children which a single donor may father and which may be designed to protect against consanguinity. However, such legislation usually cannot prevent a sperm bank from supplying donor sperm outside the jurisdiction in which it operates, and neither can it prevent sperm donors from donating elsewhere during their lives. There is an acute shortage of sperm donors in many parts of the world and there is obvious pressure from many quarters for donor sperm from those willing and able to provide it to be made available as safely and as freely as possible. | 1 | Cryobiology |
Moving parts within machines, such as the components of a gear train, normally have a small gap between them, to allow movement and lubrication. As a consequence of this gap, any reversal in direction of a drive part will not be passed on immediately to the driven part. This unwanted delay is normally kept as small as practicable, and is usually called backlash. The amount of backlash will increase with time as the surfaces of moving parts wear. | 7 | Magnetic Ordering |
Careful and detailed documentation concerning the characteristics of the starting materials (e.g. history of the cell line derivation and cell banking) and manufacturing process steps (e.g. procurement of tissue or cells and manipulation) must be maintained. The cellular part of every cell-based medicinal product must be characterized in terms of identity, purity, potency, viability and suitability for the intended use. The non-cellular constituents must be also characterized with regards to their intended function in the final product. For example, scaffolds or membranes that are used to support the cells must be identified and characterized in terms of porosity, density, microscopic structure and particular size. The same requirement for characterization applies for biologically active molecules, such as growth factors or cytokines. | 2 | Tissue Engineering |
Cryoprotectants operate by increasing the solute concentration in cells. However, in order to be biologically viable they must easily penetrate and must not be toxic to cells. | 1 | Cryobiology |
Hysteretic models are mathematical models capable of simulating complex nonlinear behavior (hysteresis) characterizing mechanical systems and materials used in different fields of engineering, such as aerospace, civil, and mechanical engineering. Some examples of mechanical systems and materials having hysteretic behavior are:
* materials, such as steel, reinforced concrete, wood;
* structural elements, such as steel, reinforced concrete, or wood joints;
* devices, such as seismic isolators and dampers.
Each subject that involves hysteresis has models that are specific to the subject. In addition, there are hysteretic models that capture general features of many systems with hysteresis. An example is the Preisach model of hysteresis, which represents a hysteresis nonlinearity as a linear superposition of square loops called non-ideal relays. Many complex models of hysteresis arise from the simple parallel connection, or superposition, of elementary carriers of hysteresis termed hysterons.
A simple and intuitive parametric description of various hysteresis loops may be found in the Lapshin model. Along with the smooth loops, substitution of trapezoidal, triangular or rectangular pulses instead of the harmonic functions allows piecewise-linear hysteresis loops frequently used in discrete automatics to be built in the model. There are implementations of the hysteresis loop model in Mathcad and in R programming language.
The Bouc–Wen model of hysteresis is often used to describe non-linear hysteretic systems. It was introduced by Bouc and extended by Wen, who demonstrated its versatility by producing a variety of hysteretic patterns. This model is able to capture in analytical form, a range of shapes of hysteretic cycles which match the behaviour of a wide class of hysteretical systems; therefore, given its versability and mathematical tractability, the Bouc–Wen model has quickly gained popularity and has been extended and applied to a wide variety of engineering problems, including multi-degree-of-freedom (MDOF) systems, buildings, frames, bidirectional and torsional response of hysteretic systems two- and three-dimensional continua, and soil liquefaction among others. The Bouc–Wen model and its variants/extensions have been used in applications of structural control, in particular in the modeling of the behaviour of magnetorheological dampers, base isolation devices for buildings and other kinds of damping devices; it has also been used in the modelling and analysis of structures built of reinforced concrete, steel, masonry and timber.. The most important extension of Bouc-Wen Model was carried out by Baber and Noori and later by Noori and co-workers. That extended model, named, BWBN, can reproduce the complex shear pinching or slip-lock phenomenon that earlier model could not reproduce. The BWBN model has been widely used in a wide spectrum of applications and implementations are available in software such as OpenSees.
Hysteretic models may have a generalized displacement as input variable and a generalized force as output variable, or vice versa. In particular, in rate-independent hysteretic models, the output variable does not depend on the rate of variation of the input one.
Rate-independent hysteretic models can be classified into four different categories depending on the type of equation that needs to be solved to compute the output variable:
* algebraic models
* transcendental models
* differential models
* integral models | 7 | Magnetic Ordering |
Vogel examined a metal sample which was allegedly given to Billy Meier by extraterrestrials, but by misinterpreting a graph on a test instrument, erroneously concluded it contained thallium, a rare metal. | 0 | Luminescence |
The timeline of solar neutrinos and their discovery dates back to the 1960s, beginning with the two astrophysicists John N. Bahcall and Raymond Davis Jr. The experiment, known as the Homestake experiment, named after the town in which it was conducted (Homestake, South Dakota), aimed to count the solar neutrinos arriving at Earth. Bahcall, using a solar model he developed, came to the conclusion that the most effective way to study solar neutrinos would be via the chlorine-argon reaction. Using his model, Bahcall was able to calculate the number of neutrinos expected to arrive at Earth from the Sun. Once the theoretical value was determined, the astrophysicists began pursuing experimental confirmation. Davis developed the idea of taking hundreds of thousands of liters of perchloroethylene, a chemical compound made up of carbon and chlorine, and searching for neutrinos using a chlorine-argon detector. The process was conducted very far underground, hence the decision to conduct the experiment in Homestake as the town was home to the Homestake Gold Mine. By conducting the experiment deep underground, Bahcall and Davis were able to avoid cosmic ray interactions which could affect the process and results. The entire experiment lasted several years as it was able to detect only a few chlorine to argon conversions each day, and the first results were not yielded by the team until 1968. To their surprise, the experimental value of the solar neutrinos present was less than 20% of the theoretical value Bahcall calculated. At the time, it was unknown if there was an error with the experiment or with the calculations, or if Bahcall and Davis did not account for all variables, but this discrepancy gave birth to what became known as the solar neutrino problem. | 3 | Nuclear Fusion |
The first transfer of an embryo from one human to another resulting in pregnancy was reported in July 1983 and subsequently led to the announcement of the first human birth 3 February 1984. This procedure was performed at the Harbor UCLA Medical Center under the direction of Dr. John Buster and the University of California at Los Angeles School of Medicine.
In the procedure, an embryo that was just beginning to develop was transferred from one woman in whom it had been conceived by artificial insemination to another woman who gave birth to the infant 38 weeks later. The sperm used in the artificial insemination came from the husband of the woman who bore the baby.
This scientific breakthrough established standards and became an agent of change for women with infertility and for women who did not want to pass on genetic disorders to their children. Donor embryo transfer has given women a mechanism to become pregnant and give birth to a child that will contain their husband's genetic makeup. Although donor embryo transfer as practiced today has evolved from the original non-surgical method, it now accounts for approximately 5% of in vitro fertilization recorded births.
Prior to this, thousands of women who were infertile, had adoption as the only path to parenthood. This set the stage to allow open and candid discussion of embryo donation and transfer. This breakthrough has given way to the donation of human embryos as a common practice similar to other donations such as blood and major organ donations. At the time of this announcement the event was captured by major news carriers and fueled healthy debate and discussion on this practice which impacted the future of reproductive medicine by creating a platform for further advancements in woman's health.
This work established the technical foundation and legal-ethical framework surrounding the clinical use of human oocyte and embryo donation, a mainstream clinical practice, which has evolved over the past 25 years. | 1 | Cryobiology |
HTK (branded as Custodiol® by Essential Pharmaceuticals LLC), has been presented by industry to surgeons as an alternative solution that exceeds other cardioplegias in myocardial protection during cardiac surgery. This claim relies on the single-dose administration of HTK compared with other multidose cardioplegias (MDC), sparing time in the adjustment of equipment during cardioplegia re-administration, allowing greater time to operate and thus a decreased CPB duration. Other benefits include a lower concentration of sodium, calcium, and potassium compared with other cardioplegias with cardiac arrest arising from the deprivation of sodium. Finally, histidine is thought to aid buffering, mannitol and tryptophan to improve membrane stability, and ketoglutarate to help ATP production during reperfusion.
A 2021 meta-analysis demonstrated no statistical advantage of HTK over blood or other crystalloid cardioplegias during adult cardiac surgery. The only practical advantage of HTK, therefore, is the single-dose administration compared to multi-dose requirements of blood and other crystalloid cardioplegia. | 1 | Cryobiology |
O-GlcNAc has been found to slow protein aggregation, though the generality of this phenomenon is unknown.
Solid-phase peptide synthesis was used to prepare full-length α-synuclein with an O-GlcNAc modification at T72. Thioflavin T aggregation assays and transmission electron microscopy demonstrated that this modified α-synuclein does not readily form aggregates.
Treatment of JNPL3 tau transgenic mice with an OGA inhibitor was shown to increase microtubule-associated protein tau O-GlcNAcylation. Immunohistochemistry analysis of the brainstem revealed decreased formation of neurofibrillary tangles. Recombinant O-GlcNAcylated tau was shown to aggregate slower than unmodified tau in an in vitro thioflavin S aggregation assay. Similar results were obtained for a recombinantly prepared O-GlcNAcylated TAB1 construct versus its unmodified form. | 6 | Carbohydrates |
Lactulose is used in the treatment of chronic constipation in patients of all ages as a long-term treatment. The dosage of lactulose for chronic idiopathic constipation is adjusted depending on the constipation severity and desired effect, from a mild stool softener to causing diarrhea. Lactulose is contraindicated in case of galactosemia, as most preparations contain the monosaccharide galactose due to its synthesis process.
Lactulose may be used to counter the constipating effects of opioids, and in the symptomatic treatment of hemorrhoids as a stool softener.
Lactulose is commonly prescribed for children who develop fear of their bowel movements and are withholders. This is because lactulose, when dosed in the proper amount, causes a bowel movement that is impossible to retain for very long. Lactulose is also used for the elderly because of its gentle and consistent results. | 6 | Carbohydrates |
Under a given uni-axial mechanical stress , the flux density for a given magnetizing field strength may increase or decrease. The way in which a material responds to stresses depends on its saturation magnetostriction . For this analysis, compressive stresses are considered as negative, whereas tensile stresses are positive.<br />
According to Le Chatelier's principle:
This means, that when the product is positive, the flux density increases under stress. On the other hand, when the product is negative, the flux density decreases under stress. This effect was confirmed experimentally. | 7 | Magnetic Ordering |
Tengion, Inc. is an American development-stage regenerative medicine company founded in 2003 with financing from J&J Development Corporation, HealthCap and Oak Investment Partners, which is headquartered in Winston-Salem, North Carolina. Its goals are discovering, developing, manufacturing and commercializing a range of replacement organs and tissues, or neo-organs and neo-tissues, to address unmet medical needs in urologic, renal, gastrointestinal, and vascular diseases and disorders. The company creates these human neo-organs from a patient’s own cells or autologous cells, in conjunction with its Organ Regeneration Platform.
The company declared Chapter 7 bankruptcy in December 2014, and it, along with its assets and tissue engineering samples, have been bought back by its creditors and former executives as of March 2015. The purchase was expedited, so that time-sensitive research can continue. | 2 | Tissue Engineering |
Histone proteins, the primary protein component of chromatin, are known to be modified by O-GlcNAc. O-GlcNAc has been identified on all core histones (H2A, H2B, H3, and H4). The presence of O-GlcNAc on histones has been suggested to affect gene transcription as well as other histone marks such as acetylation and monoubiquitination. TET2 has been reported to interact with the TPR domain of OGT and facilitate recruitment of OGT to histones. This interaction is associated with H2B S112 O-GlcNAc, which in turn is associated with H2B K120 monoubiquitination. Phosphorylation of OGT T444 via AMPK has been found to inhibit OGT-chromatin association and downregulate H2B S112 O-GlcNAc. | 6 | Carbohydrates |
Unlike the helium hydride ion, the neutral helium hydride molecule HeH is not stable in the ground state. However, it does exist in an excited state as an excimer (HeH*), and its spectrum was first observed in the mid-1980s.
The neutral molecule is the first entry in the Gmelin database. | 4 | Acids + Bases |
UVGI is often used to disinfect equipment such as safety goggles, instruments, pipettors, and other devices. Lab personnel also disinfect glassware and plasticware this way. Microbiology laboratories use UVGI to disinfect surfaces inside biological safety cabinets ("hoods") between uses. | 8 | Ultraviolet Radiation |
The second approach of bioprinting is autonomous self-assembly. This approach relies on the physical process of embryonic organ development as a model to replicate the tissues of interest. When cells are in their early development, they create their own extracellular matrix building block, the proper cell signaling, and independent arrangement and patterning to provide the required biological functions and micro-architecture. Autonomous self-assembly demands specific information about the developmental techniques of the tissues and organs of the embryo. There is a "scaffold-free" model that uses self-assembling spheroids that subjects to fusion and cell arrangement to resemble evolving tissues. Autonomous self-assembly depends on the cell as the fundamental driver of histogenesis, guiding the building blocks, structural and functional properties of these tissues. It demands a deeper understanding of how embryonic tissues mechanisms develop as well as the microenvironment surrounded to create the bioprinted tissues. | 2 | Tissue Engineering |
Additional helium atoms can attach to HeH to form larger clusters such as HeH, HeH, HeH, HeH and HeH.
The dihelium hydride cation, HeH, is formed by the reaction of dihelium cation with molecular hydrogen:
: + H → HeH + H
It is a linear ion with hydrogen in the centre.
The hexahelium hydride ion, HeH, is particularly stable.
Other helium hydride ions are known or have been studied theoretically. Helium dihydride ion, or dihydridohelium(1+), , has been observed using microwave spectroscopy. It has a calculated binding energy of 25.1 kJ/mol, while trihydridohelium(1+), , has a calculated binding energy of 0.42 kJ/mol. | 4 | Acids + Bases |
Jiří Linhart (13 April 1924 – 6 January 2011) Nuclear fusion physicist and Czech Olympic swimmer. He competed in the men's 200 metre breaststroke at the 1948 Summer Olympics in London. He stayed on in London after which he took his PhD under the supervision of Denis Gabor. He was a pioneer of Nuclear Fusion, author of [https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/abs/plasma-physics-by-j-g-linhart-amsterdam-north-holland-publishing-co-1960-278-pp-50s/B5B22BC6E784AF39819CB8F40B17D112# "Plasma Physics" (1960) - the first textbook on Plasma science], and many [https://iopscience.iop.org/article/10.1088/0029-5515/10/3/001 academic papers] and early [https://www.freepatentsonline.com/3113917.html patents on nuclear reactors].
In 1956 he became group Head of Acceleration at CERN, and in 1960 he became the head of the EURATOM group in Frascati.
He was also a very keen chess player, playing in the [https://www.chessgames.com/perl/chessplayer?pid=161073 Haifa Olympiad in 1976.] | 3 | Nuclear Fusion |
The magnetoelastic energy describes the energy storage due to elastic lattice distortions. It may be neglected if magnetoelastic coupled effects are neglected.
There exists a preferred local distortion of the crystalline solid associated with the magnetization director m, .
For a simple model, one can assume this strain to be isochoric and fully
isotropic in the lateral direction, yielding the deviatoric ansatz
where the material parameter E > 0 is the magnetostrictive
constant. Clearly, E is the strain induced by the magnetization in
the direction m. With this ansatz at hand, we consider the elastic
energy density to be a function of the elastic, stress-producing
strains . A quadratic form for the magnetoelastic energy is
where
is the fourth-order elasticity tensor. Here the elastic response is assumed to be isotropic (based on
the two Lamé constants λ and μ).
Taking into account the constant length of m, we obtain the invariant-based representation
This energy term contributes to magnetostriction. | 7 | Magnetic Ordering |
IVF is expensive in China and not generally accessible to unmarried women. In August 2022, China's National Health Authority announced that it will take steps to make assisted reproductive technology more accessible, including by guiding local governments to include such technology in its national medical system.
Croatia
No egg or sperm donations take place in Croatia, however using donated sperm or egg in ART and IUI is allowed. With donated eggs, sperm or embryo, a heterosexual couple and single women have legal access to IVF. Male or female couples do not have access to ART as a form of reproduction. The minimum age for males and females to access ART in Croatia is 18 there is no maximum age. Donor anonymity applies, but the born child can be given access to the donor's identity at a certain age | 1 | Cryobiology |
Sonoluminescence is a phenomenon that occurs when a small gas bubble is acoustically suspended and periodically driven in a liquid solution at ultrasonic frequencies, resulting in bubble collapse, cavitation, and light emission. The thermal energy that is released from the bubble collapse is so great that it can cause weak light emission. The mechanism of the light emission remains uncertain, but some of the current theories, which are categorized under either thermal or electrical processes, are Bremsstrahlung radiation, argon rectification hypothesis, and hot spot. Some researchers are beginning to favor thermal process explanations as temperature differences have consistently been observed with different methods of spectral analysis. In order to understand the light emission mechanism, it is important to know what is happening in the bubbles interior and at the bubbles surface. | 0 | Luminescence |
*Massachusetts Institute of Technology (MIT)
*Carnegie Institute
*Westinghouse Electric Corporation
*Gould-National Batteries, Inc.
*General Electrical Company | 3 | Nuclear Fusion |
This compound is prepared by treatment of NaBAr′ in diethyl ether (EtO) with hydrogen chloride:
: NaBAr′ + HCl + 2 EtO → [H(OEt)] + NaCl
NaBAr′ is soluble in diethyl ether, whereas sodium chloride is not. Precipitation of sodium chloride thus drives the formation of the oxonium acid compound, which is isolable as a solid. | 4 | Acids + Bases |
This method is related to the downdraft, but uses a pump to power a spray nozzle, fixed a few inches above the water level. The spray action entraps and shreds the air in the base of the unit, similar to holding your thumb over a garden hose, which then rises to the collection chamber. In the United States, one company has patented the spray induction technology and the commercial product offerings are limited to that single company. | 5 | Separation Processes |
Embryo transfer refers to a step in the process of assisted reproduction in which embryos are placed into the uterus of a female with the intent to establish a pregnancy. This technique - which is often used in connection with in vitro fertilization (IVF) - may be used in humans or in other animals, in which situations and goals may vary.
Embryo transfer can be done at day two or day three, or later in the blastocyst stage, which was first performed in 1984.
Factors that can affect the success of embryo transfer include the endometrial receptivity, embryo quality, and embryo transfer technique. | 1 | Cryobiology |
Ordinarily, the probability of the triple-alpha process is extremely small. However, the beryllium-8 ground state has almost exactly the energy of two alpha particles. In the second step, Be + He has almost exactly the energy of an excited state of C. This resonance greatly increases the probability that an incoming alpha particle will combine with beryllium-8 to form carbon. The existence of this resonance was predicted by Fred Hoyle before its actual observation, based on the physical necessity for it to exist, in order for carbon to be formed in stars. The prediction and then discovery of this energy resonance and process gave very significant support to Hoyle's hypothesis of stellar nucleosynthesis, which posited that all chemical elements had originally been formed from hydrogen, the true primordial substance. The anthropic principle has been cited to explain the fact that nuclear resonances are sensitively arranged to create large amounts of carbon and oxygen in the universe. | 3 | Nuclear Fusion |
Psychrophiles are protected from freezing and the expansion of ice by ice-induced desiccation and vitrification (glass transition), as long as they cool slowly. Free living cells desiccate and vitrify between −10 °C and −26 °C. Cells of multicellular organisms may vitrify at temperatures below −50 °C. The cells may continue to have some metabolic activity in the extracellular fluid down to these temperatures, and they remain viable once restored to normal temperatures.
They must also overcome the stiffening of their lipid cell membrane, as this is important for the survival and functionality of these organisms. To accomplish this, psychrophiles adapt lipid membrane structures that have a high content of short, unsaturated fatty acids. Compared to longer saturated fatty acids, incorporating this type of fatty acid allows for the lipid cell membrane to have a lower melting point, which increases the fluidity of the membranes. In addition, carotenoids are present in the membrane, which help modulate the fluidity of it.
Antifreeze proteins are also synthesized to keep psychrophiles internal space liquid, and to protect their DNA when temperatures drop below waters freezing point. By doing so, the protein prevents any ice formation or recrystallization process from occurring.
The enzymes of these organisms have been hypothesized to engage in an activity-stability-flexibility relationship as a method for adapting to the cold; the flexibility of their enzyme structure will increase as a way to compensate for the freezing effect of their environment.
Certain cryophiles, such as Gram-negative bacteria Vibrio and Aeromonas spp., can transition into a viable but nonculturable (VBNC) state. During VBNC, a micro-organism can respire and use substrates for metabolism – however, it cannot replicate. An advantage of this state is that it is highly reversible. It has been debated whether VBNC is an active survival strategy or if eventually the organism's cells will no longer be able to be revived. There is proof however it may be very effective – Gram positive bacteria Actinobacteria have been shown to have lived about 500,000 years in the permafrost conditions of Antarctica, Canada, and Siberia. | 1 | Cryobiology |
Hand-counting is a cheap and easy to conduct method to estimate the liberation characteristics of a bulk sample wither originating from run-of-mine material, a waste dump or for example exploration trenching. Analysis of particles in the size range 10-100mm has been conducted on a total sample mass of 10 tonnes. By visual inspection of trained personnel, a classification of each particle into different bins (e.g. lithology, grade) is possible and the distribution is determined by weighing each bin. A trained professional can quickly estimate the efficiency of a specific detection and process efficiency of sensor-based ore sorting knowing the sensor response of the mineralogy of ore in question and other process efficiency parameters. | 5 | Separation Processes |
A 2006 project at University of California, Berkeley produced a design for inexpensive water disinfection in resource deprived settings. The project was designed to produce an open source design that could be adapted to meet local conditions. In a somewhat similar proposal in 2014, Australian students designed a system using potato chip (crisp) packet foil to reflect solar UV radiation into a glass tube that disinfects water without power. | 8 | Ultraviolet Radiation |
There are a number of methods through which hypothermia is induced. These include: cooling catheters, cooling blankets, and application of ice applied around the body among others. As of 2013 it is unclear if one method is any better than the others. While cool intravenous fluid may be given to start the process, further methods are required to keep the person cold.
Core body temperature must be measured (either via the esophagus, rectum, bladder in those who are producing urine, or within the pulmonary artery) to guide cooling. A temperature below should be avoided, as adverse events increase significantly. The person should be kept at the goal temperature plus or minus half a degree Celsius for 24 hours. Rewarming should be done slowly with suggested speeds of per hour.
Targeted temperature management should be started as soon as possible. The goal temperature should be reached before 8 hours. Targeted temperature management remains partially effective even when initiated as long as 6 hours after collapse.
Prior to the induction of targeted temperature management, pharmacological agents to control shivering must be administered. When body temperature drops below a certain threshold—typically around —people may begin to shiver. It appears that regardless of the technique used to induce hypothermia, people begin to shiver when temperature drops below this threshold. Drugs commonly used to prevent and treat shivering in targeted temperature management include acetaminophen, buspirone, opioids including pethidine (meperidine), dexmedetomidine, fentanyl, and/or propofol. If shivering is unable to be controlled with these drugs, patients are often placed under general anesthesia and/or are given paralytic medication like vecuronium. People should be rewarmed slowly and steadily in order to avoid harmful spikes in intracranial pressure. | 1 | Cryobiology |
The Food and Drug Administration (FDA) classifies tanning beds as "moderate risk" devices (changed in 2014 from "low risk"). It requires that devices carry a black box warning that they should not be used by individuals under the age of 18, but it has not banned their use by minors. , California, Delaware, the District of Columbia, Hawaii, Illinois, Kansas, Louisiana, Massachusetts, Minnesota, Nevada, New Hampshire, North Carolina, Oregon, Texas, Vermont and Washington have banned the use of tanning beds for minors under the age of 18. Other states strictly regulate indoor tanning under the age of 18, with most banning indoor tanning for persons under the age of 14 unless medically required, and some requiring the consent of a guardian for those aged 14–17. In 2010 under the Affordable Care Act, a 10% "tanning tax" was introduced, which is added to the fees charged by tanning facilities; it was expected to raise $2.7 billion for health care over ten years.
Tanning beds are regulated in the United States by the federal governments Code of Federal Regulations (21 CFR 1040.20). This is designed to ensure that the devices adhere to a set of safety rules, with the primary focus on sunbed and lamp manufacturers regarding maximum exposure times and product equivalence. Additionally, must have a "Recommended Exposure Schedule" posted on both the front of the tanning bed and in the owners manual, and list the original lamp that was certified for that particular tanning bed. Salon owners are required to replace the lamps with either exactly the same lamp, or a lamp that is certified by the lamp manufacturer to be.
States control regulations for salons, regarding operator training, sanitization of sunbeds and eyewear, and additional warning signs. Many states also ban or regulate the use of tanning beds by minors under the age of 18.
American osteopathic physician Joseph Mercola was prosecuted in 2016 by the Federal Trade Commission (FTC) for selling tanning beds to "reverse your wrinkles" and "slash your risk of cancer". The settlement meant that consumers who had purchased the devices were eligible for refunds totalling $5.3 million. Mercola had falsely claimed that the FDA "endorsed indoor tanning devices as safe", and had failed to disclose that he had paid the Vitamin D Council for its endorsement of his devices. The FTC said that it was deceptive for the defendants to fail to disclose that tanning is not necessary to produce vitamin D. | 8 | Ultraviolet Radiation |
As the concentration of particles in a suspension is increased, a point is reached where particles are so close together that they no longer settle independently of one another and the velocity fields of the fluid displaced by adjacent particles, overlap. There is also a net upward flow of liquid displaced by the settling particles. This results in a reduced particle-settling velocity and the effect is known as hindered settling.
There is a common case for hindered settling occurs. the whole suspension tends to settle as a ‘blanket’ due to its extremely high particle concentration. This is known as zone settling, because it is easy to make a distinction between several different zones which separated by concentration discontinuities. Fig. 3 represents a typical batch-settling column tests on a suspension exhibiting zone-settling characteristics. There is a clear interface near the top of the column would be formed to separating the settling sludge mass from the clarified supernatant as long as leaving such a suspension to stand in a settling column. As the suspension settles, this interface will move down at the same speed. At the same time, there is an interface near the bottom between that settled suspension and the suspended blanket. After settling of suspension is complete, the bottom interface would move upwards and meet the top interface which moves downwards. | 5 | Separation Processes |
More sophisticated variants of sublimation apparatus include those that apply a temperature gradient so as to allow for controlled recrystallization of different fractions along the cold surface. Thermodynamic processes follow a statistical distribution, and suitably designed apparatus exploit this principle with a gradient that will yield different purities in particular temperature zones along the collection surface. Such techniques are especially helpful when the requirement is to refine or separate multiple products or impurities from the same mix of raw materials. It is necessary in particular when some of the required products have similar sublimation points or pressure curves. | 5 | Separation Processes |
Fructose, along with glucose, is one of the principal sugars involved in the creation of wine. At time of harvest, there is usually an equal amount of glucose and fructose molecules in the grape; however, as the grape overripens the level of fructose will become higher. In wine, fructose can taste nearly twice as sweet as glucose and is a key component in the creation of sweet dessert wines. During fermentation, glucose is consumed first by the yeast and converted into alcohol. A winemaker that chooses to halt fermentation (either by temperature control or the addition of brandy spirits in the process of fortification) will be left with a wine that is high in fructose and notable residual sugars. The technique of süssreserve, where unfermented grape must is added after the wine's fermentation is complete, will result in a wine that tastes less sweet than a wine whose fermentation was halted. This is because the unfermented grape must will still have roughly equal parts of fructose and the less sweet tasting glucose. Similarly, the process of chaptalization where sucrose (which is one part glucose and one part fructose) is added will usually not increase the sweetness level of the wine. | 6 | Carbohydrates |
UV pinning enhances the management of drop size and image integrity, minimizing the unwanted mixing of drops and providing the highest possible image quality and the sharpest colour rendering.
Challenge:
Overcome the wetting problems that were causing UV-Curable inks to spread and cause ink droplets to bleed into each other before full curing single-pass digital printing of narrow web labels.
Solution:
A UV pinning system that uses high power UV light emitting diodes(LEDs) installed next to the inkjet array (print head). The UV light from the pinning system, typically lower than that of the full cure UV system, causes the UV ink to thicken, also known as gelling, but not fully cure. This ink thickening stops dot gain and holds the ink droplet pattern in place until it reaches the full cure UV system. | 8 | Ultraviolet Radiation |
Tissue engineered heart valves offer certain advantages over traditional biological and mechanical valves:
* Living valve – The option of a living heart valve replacement is highly optimal for children as the live valve has the ability to grow and respond to its biological environment, which is especially beneficial for children whose bodies are continually changing. This option would help reduce the number of reoperation needed in a child's life.
* Customized process – Since the scaffolds used in tissue engineering can be manufactured from scratch, there is a higher degree of flexibility and control. This allows the potential of tailoring tissue engineered heart valves and its properties such as the scaffold's shape and biomaterial makeup to be tailored specifically to the patient. | 2 | Tissue Engineering |
Thermonuclear weapons, also known as hydrogen bombs, are nuclear weapons that use energy released by a burning plasma's fusion reactions to produce part of their explosive yield. This is in contrast to pure-fission weapons, which produce all of their yield from a neutronic nuclear fission reaction. The first thermonuclear explosion, and thus the first man-made burning plasma, was the Ivy Mike test carried out by the United States in 1952. All high-yield nuclear weapons today are thermonuclear weapons. | 3 | Nuclear Fusion |
Fung's famous exponential strain constitutive equation for preconditioned soft tissues is
with
quadratic forms of Green-Lagrange strains and , and material constants. is a strain energy function per volume unit, which is the mechanical strain energy for a given temperature. Materials that follow this law are known as Fung-elastic. | 2 | Tissue Engineering |
One of the first companies to begin experimenting with hair cloning was Intercytex. Researchers at the company were convinced that their approach was the cure for baldness, and if the technology is fully developed, they can basically eliminate hair loss due to hereditary factors. This therapy would also eliminate the need for donor hair, as it can be simply grown from the patient's own cells.
Intercytex tried to clone new hair follicles from the stem cells harvested from the back of the neck. They hoped that if they multiplied (cloned) the follicles and then implanted them back in the scalp in the bald areas they would be successful in regrowing the hair itself. They tested the method in their Phase II trials, which showed very promising results as two-thirds of the bald male patients were able to grow new hair after the treatment.
The company was hoping to complete the research so they can make it available to the public, so they began Phase III trials. They estimated they would be able to finish the process in a few years. However, these tests did not show the expected progress. In 2008 Intercytex admitted that they failed in fully developing the hair cloning therapy and decided to discontinue all research.
This was not solely the result of the failed tests, as the company's financial background also became unstable in 2008 and they had to implement several cost-cutting measures. They laid off a great number of staff members and cut funding to the research projects such as hair cloning. In 2010 they went out of business. | 2 | Tissue Engineering |
Chloroauric acid is a strong eye, skin, and mucous membrane irritant. Prolonged skin contact with chloroauric acid may result in tissue destruction. Concentrated chloroauric acid is corrosive to skin and must, therefore, be handled with appropriate care, since it can cause skin burns, permanent eye damage, and irritation to mucous membranes. Gloves are worn when handling the compound. | 4 | Acids + Bases |
While many in vitro and in vivo studies have been tested in animal models, the translation from animal models to humans has not begun. Factors such as the size of surgical cut sites, duration of the procedure, and available resources and cost must all be considered. Synthetic nanomaterials have the potential to advance scaffoldings used in tissue engineering of heart valves. The use of nanotechnology could help expand beneficial properties of fabricated scaffolds such as higher tensile strength. | 2 | Tissue Engineering |
Radioluminescence occurs when an incoming particle of ionizing radiation collides with an atom or molecule, exciting an orbital electron to a higher energy level. The particle usually comes from the radioactive decay of an atom of a radioisotope, an isotope of an element which is radioactive. The electron then returns to its ground energy level by emitting the extra energy as a photon of light. A chemical that releases light of a particular color when struck by ionizing radiation is called a phosphor. Radioluminescent light sources usually consist of a radioactive substance mixed with, or in proximity to, a phosphor. | 0 | Luminescence |
Burning of the most abundant isotope of lithium, lithium-7, occurs by a collision of Li and a proton producing beryllium-8, which promptly decays into two helium-4 nuclei. The temperature necessary for this reaction is just below the temperature necessary for hydrogen fusion. Convection in low-mass stars ensures that lithium in the whole volume of the star is depleted. Therefore, the presence of the lithium line in a candidate brown dwarf's spectrum is a strong indicator that it is indeed substellar. | 3 | Nuclear Fusion |
There are three main components to the hybrid fusion fuel cycle: deuterium, tritium, and fissionable elements. Deuterium can be derived by the separation of hydrogen isotopes in seawater (see heavy water production). Tritium may be generated in the hybrid process itself by absorption of neutrons in lithium bearing compounds. This would entail an additional lithium-bearing blanket and a means of collection. Small amounts of tritium are also produced by neutron activation in nuclear fission reactors, particularly when heavy water is used as a neutron moderator or coolant. The third component is externally derived fissionable materials from demilitarized supplies of fissionables, or commercial nuclear fuel and waste streams. Fusion driven fission also offers the possibility of using thorium as a fuel, which would greatly increase the potential amount of fissionables available. The extremely energetic nature of the fast neutrons emitted during the fusion events (up to 0.17 the speed of light) can allow normally non-fissioning U to undergo fission directly (without conversion first to Pu), enabling refined natural Uranium to be used with very low enrichment, while still maintaining a deeply subcritical regime. | 3 | Nuclear Fusion |
In the elastic hysteresis of rubber, the area in the centre of a hysteresis loop is the energy dissipated due to material internal friction.
Elastic hysteresis was one of the first types of hysteresis to be examined.
The effect can be demonstrated using a rubber band with weights attached to it. If the top of a rubber band is hung on a hook and small weights are attached to the bottom of the band one at a time, it will stretch and get longer. As more weights are loaded onto it, the band will continue to stretch because the force the weights are exerting on the band is increasing. When each weight is taken off, or unloaded, the band will contract as the force is reduced. As the weights are taken off, each weight that produced a specific length as it was loaded onto the band now contracts less, resulting in a slightly longer length as it is unloaded. This is because the band does not obey Hooke's law perfectly. The hysteresis loop of an idealized rubber band is shown in the figure.
In terms of force, the rubber band was harder to stretch when it was being loaded than when it was being unloaded. In terms of time, when the band is unloaded, the effect (the length) lagged behind the cause (the force of the weights) because the length has not yet reached the value it had for the same weight during the loading part of the cycle. In terms of energy, more energy was required during the loading than the unloading, the excess energy being dissipated as thermal energy.
Elastic hysteresis is more pronounced when the loading and unloading is done quickly than when it is done slowly. Some materials such as hard metals don't show elastic hysteresis under a moderate load, whereas other hard materials like granite and marble do. Materials such as rubber exhibit a high degree of elastic hysteresis.
When the intrinsic hysteresis of rubber is being measured, the material can be considered to behave like a gas. When a rubber band is stretched it heats up, and if it is suddenly released, it cools down perceptibly. These effects correspond to a large hysteresis from the thermal exchange with the environment and a smaller hysteresis due to internal friction within the rubber. This proper, intrinsic hysteresis can be measured only if the rubber band is thermally isolated.
Small vehicle suspensions using rubber (or other elastomers) can achieve the dual function of springing and damping because rubber, unlike metal springs, has pronounced hysteresis and does not return all the absorbed compression energy on the rebound. Mountain bikes have made use of elastomer suspension, as did the original Mini car.
The primary cause of rolling resistance when a body (such as a ball, tire, or wheel) rolls on a surface is hysteresis. This is attributed to the viscoelastic characteristics of the material of the rolling body. | 7 | Magnetic Ordering |
The usual measure of the strength of an acid is its acid dissociation constant (), which can be determined experimentally by titration methods. Stronger acids have a larger and a smaller logarithmic constant () than weaker acids. The stronger an acid is, the more easily it loses a proton, . Two key factors that contribute to the ease of deprotonation are the polarity of the bond and the size of atom A, which determine the strength of the bond. Acid strengths also depend on the stability of the conjugate base.
While the value measures the tendency of an acidic solute to transfer a proton to a standard solvent (most commonly water or DMSO), the tendency of an acidic solvent to transfer a proton to a reference solute (most commonly a weak aniline base) is measured by its Hammett acidity function, the value. Although these two concepts of acid strength often amount to the same general tendency of a substance to donate a proton, the and values are measures of distinct properties and may occasionally diverge. For instance, hydrogen fluoride, whether dissolved in water ( = 3.2) or DMSO ( = 15), has values indicating that it undergoes incomplete dissociation in these solvents, making it a weak acid. However, as the rigorously dried, neat acidic medium, hydrogen fluoride has an value of –15, making it a more strongly protonating medium than 100% sulfuric acid and thus, by definition, a superacid. (To prevent ambiguity, in the rest of this article, "strong acid" will, unless otherwise stated, refer to an acid that is strong as measured by its value ( < –1.74). This usage is consistent with the common parlance of most practicing chemists.)
When the acidic medium in question is a dilute aqueous solution, the is approximately equal to the pH value, which is a negative logarithm of the concentration of aqueous in solution. The pH of a simple solution of an acid in water is determined by both and the acid concentration. For weak acid solutions, it depends on the degree of dissociation, which may be determined by an equilibrium calculation. For concentrated solutions of acids, especially strong acids for which pH value is a better measure of acidity than the pH. | 4 | Acids + Bases |
In 2010, NIF researchers conducted a series of "tuning" shots to determine the optimal target design and laser parameters for high-energy ignition experiments with fusion fuel. Net fuel energy gain was achieved in September 2013.
In April 2014, LLNL ended the Laser Inertial Fusion Energy (LIFE) program and directed their efforts towards NIF.
A 2012 paper demonstrated that a dense plasma focus had achieved temperatures of 1.8 billion degrees Celsius, sufficient for boron fusion, and that fusion reactions were occurring primarily within the contained plasmoid, necessary for net power.
In August 2014, MIT announced a tokamak it named the ARC fusion reactor, using rare-earth barium-copper oxide (REBCO) superconducting tapes to construct high-magnetic field coils that it claimed produced comparable magnetic field strength in a smaller configuration than other designs.
In October 2015, researchers at the Max Planck Institute of Plasma Physics completed building the largest stellarator to date, the Wendelstein 7-X. In December they produced the first helium plasma, and in February 2016 produced hydrogen plasma. In 2015, with plasma discharges lasting up to 30 minutes, Wendelstein 7-X attempted to demonstrate the essential stellarator attribute: continuous operation of a high-temperature plasma.
In 2014 EAST achieved a record confinement time of 30 seconds for plasma in the high-confinement mode (H-mode), thanks to improved heat dispersal. This was an order of magnitude improvement vs other reactors. In 2017 the reactor achieved a stable 101.2-second steady-state high confinement plasma, setting a world record in long-pulse H-mode operation.
In 2018 MIT scientists formulated a theoretical means to remove the excess heat from compact nuclear fusion reactors via larger and longer divertors.
In 2019 the United Kingdom announced a planned £200-million (US$248-million) investment to produce a design for a fusion facility named the Spherical Tokamak for Energy Production (STEP), by the early 2040s. | 3 | Nuclear Fusion |
21st Century Medicine (21CM) is a California cryobiological research company which has as its primary focus the development of perfusates and protocols for viable long-term cryopreservation of human organs, tissues and cells at temperatures below −100 °C through the use of vitrification. 21CM was founded in 1993.
In 2004 21CM received a $900,000 grant from the U.S. National Institutes of Health (NIH) to study a preservation solution developed by the University of Rochester in New York for extending simple cold storage time of human hearts removed for transplant.
At the July 2005 annual conference of the Society for Cryobiology, 21st Century Medicine announced the vitrification of a rabbit kidney to −135 °C with their vitrification mixture. The kidney was successfully transplanted upon rewarming to a rabbit, the rabbit being euthanized on the 48th day for histological follow-up.
On February 9, 2016, 21st Century Medicine won the Small Mammal Brain Preservation Prize. On March 13, 2018, they won the Large Mammal Brain Preservation Prize. | 1 | Cryobiology |
In scanning electron microscopes a focused beam of electrons impinges on a sample and induces it to emit light that is collected by an optical system, such as an elliptical mirror. From there, a fiber optic will transfer the light out of the microscope where it is separated into its component wavelengths by a monochromator and is then detected with a photomultiplier tube. By scanning the microscope's beam in an X-Y pattern and measuring the light emitted with the beam at each point, a map of the optical activity of the specimen can be obtained (cathodoluminescence imaging). Instead, by measuring the wavelength dependence for a fixed point or a certain area, the spectral characteristics can be recorded (cathodoluminescence spectroscopy). Furthermore, if the photomultiplier tube is replaced with a CCD camera, an entire spectrum can be measured at each point of a map (hyperspectral imaging). Moreover, the optical properties of an object can be correlated to structural properties observed with the electron microscope.
The primary advantages to the electron microscope based technique is its spatial resolution. In a scanning electron microscope, the attainable resolution is on the order of a few ten nanometers, while in a (scanning) transmission electron microscope (TEM), nanometer-sized features can be resolved. Additionally, it is possible to perform nanosecond- to picosecond-level time-resolved measurements if the electron beam can be "chopped" into nano- or pico-second pulses by a beam-blanker or with a pulsed electron source. These advanced techniques are useful for examining low-dimensional semiconductor structures, such a quantum wells or quantum dots.
While an electron microscope with a cathodoluminescence detector provides high magnification, an optical cathodoluminescence microscope benefits from its ability to show actual visible color features directly through the eyepiece. More recently developed systems try to combine both an optical and an electron microscope to take advantage of both these techniques. | 0 | Luminescence |
Another option studied was using decellularized biological scaffolds and seeding them with their corresponding cells in vitro. In 2000, Steinhoff implanted a decellularized sheep pulmonary valve scaffold seeded with sheep endothelial cells and myofibroblasts. Dohmen then created a decellularized cryopreserved pulmonary allograft scaffold and seeded it with human vascular endothelial cells to reconstruct the right ventricular outflow tract (RVOT) in a human patient in 2002. Perry in 2003 seeded a P4HB coated PGA scaffold with sheep mesenchymal stem cells in vitro; however, an in vivo study was not performed. In 2004, Iwai conducted a study using a poly(lactic-co-glycolic acid) PLGA compounded with collagen microsponge sphere scaffold, which was seeded with endothelial and smooth muscle cells at the site of a dog's pulmonary artery. Sutherland in 2005 utilized a sheep mesenchymal stem cell seeded PGA and poly-L-lactic acid (PLLA) scaffold to replace all three pulmonary valve leaflets in a sheep. | 2 | Tissue Engineering |
Solid acids are acids that are insoluble in the reaction medium. They are often used as heterogeneous catalysts. | 4 | Acids + Bases |
In chemical separation processes, a mass separating agent (MSA) is a chemical species that is added to ensure that the intended separation process takes place. It is analogous to an energy separating agent, which aids separations processes via addition of energy. An MSA may be partially immiscible with one or more mixture components and frequently is the constituent of highest concentration in the added phase. Alternatively, the MSA may be miscible with a liquid feed mixture, but may selectively alter partitioning of species between liquid and vapor phases.
Disadvantages of using an MSA are a need for an additional separator to recover the MSA for recycle, a need for MSA makeup, possible MSA product contamination, and more difficult design procedures.
Processes like absorption and stripping generally utilize various MSAs. | 5 | Separation Processes |
An increasingly popular method of cleaning windows is the "water-fed pole" system. Instead of washing windows with conventional detergent, they are scrubbed with purified water, typically containing less than 10 ppm dissolved solids, using a brush on the end of a pole wielded from ground level. RO is commonly used to purify the water. | 5 | Separation Processes |
Ultraviolet radiation is helpful in the treatment of skin conditions such as psoriasis and vitiligo. Exposure to UVA, while the skin is hyper-photosensitive, by taking psoralens is an effective treatment for psoriasis. Due to the potential of psoralens to cause damage to the liver, PUVA therapy may be used only a limited number of times over a patient's lifetime.
UVB phototherapy does not require additional medications or topical preparations for the therapeutic benefit; only the exposure is needed. However, phototherapy can be effective when used in conjunction with certain topical treatments such as anthralin, coal tar, and vitamin A and D derivatives, or systemic treatments such as methotrexate and Soriatane. | 8 | Ultraviolet Radiation |
With the help of lithography techniques, it is possible to fabricate sub-micrometer size magnetic islands whose geometric arrangement reproduces the frustration found in naturally occurring spin ice materials. Recently R. F. Wang et al. reported the discovery of an artificial geometrically frustrated magnet composed of arrays of lithographically fabricated single-domain ferromagnetic islands. These islands are manually arranged to create a two-dimensional analog to spin ice. The magnetic moments of the ordered ‘spin’ islands were imaged with magnetic force microscopy (MFM) and then the local accommodation of frustration was thoroughly studied. In their previous work on a square lattice of frustrated magnets, they observed both ice-like short-range correlations and the absence of long-range correlations, just like in the spin ice at low temperature. These results solidify the uncharted ground on which the real physics of frustration can be visualized and modeled by these artificial geometrically frustrated magnets, and inspires further research activity.
These artificially frustrated ferromagnets can exhibit unique magnetic properties when studying their global response to an external field using Magneto-Optical Kerr Effect. In particular, a non-monotonic angular dependence of the square lattice coercivity is found to be related to disorder in the artificial spin ice system. | 7 | Magnetic Ordering |
Sensor-based sorting has been introduced by Wotruba and Harbeck as an umbrella term for all applications where particles are singularly detected by a sensor technique and then rejected by an amplified mechanical, hydraulic or pneumatic process. | 5 | Separation Processes |
Nuclear DNA is injured during cold storage of kidneys. Lazarus showed that single stranded DNA breaks occurred within 16 hours in hypothermically stored mice kidneys, with the injury being inhibited a little by storage in Collins or Sacks solutions. This nuclear injury differed from that seen in warm injury when double stranded DNA breaks occurred. | 1 | Cryobiology |
There are a great variety of applications of the hysteresis in ferromagnets. Many of these make use of their ability to retain a memory, for example magnetic tape, hard disks, and credit cards. In these applications, hard magnets (high coercivity) like iron are desirable, such that as much energy is absorbed as possible during the write operation and the resultant magnetized information is not easily erased.
On the other hand, magnetically soft (low coercivity) iron is used for the cores in electromagnets. The low coercivity minimizes the energy loss associated with hysteresis, as the magnetic field periodically reverses in the presence of an alternating current. The low energy loss during a hysteresis loop is the reason why soft iron is used for transformer cores and electric motors. | 7 | Magnetic Ordering |
Systems with rate-independent hysteresis have a persistent memory of the past that remains after the transients have died out. The future development of such a system depends on the history of states visited, but does not fade as the events recede into the past. If an input variable cycles from to and back again, the output may be initially but a different value upon return. The values of depend on the path of values that passes through but not on the speed at which it traverses the path. Many authors restrict the term hysteresis to mean only rate-independent hysteresis. Hysteresis effects can be characterized using the Preisach model and the generalized Prandtl−Ishlinskii model. | 7 | Magnetic Ordering |
Lattice confinement fusion (LCF) is a type of nuclear fusion in which deuteron-saturated metals are exposed to gamma radiation or ion beams, such as in an IEC fusor, avoiding the confined high-temperature plasmas used in other methods of fusion. | 3 | Nuclear Fusion |
3D organ printing technology permits the fabrication of high degrees of complexity with great reproducibility, in a fast and cost-effective manner. 3D printing has been used in pharmaceutical research and fabrication, providing a transformative system allowing precise control of droplet size and dose, personalized medicine, and the production of complex drug-release profiles. This technology calls for implantable drug delivery devices, in which the drug is injected into the 3D printed organ and is released once in vivo. Also, organ printing has been used as a transformative tool for in vitro testing. The printed organ can be utilized in discovery and dosage research upon drug-release factors. | 2 | Tissue Engineering |
Magnetomechanical effects connect magnetic, mechanical and electric phenomena in solid materials.
* Magnetostriction
* Inverse magnetostrictive effect
* Wiedemann effect
* Matteucci effect
* Guillemin effect
Magnetostriction is thermodynamically opposite to inverse magnetostriction effect. The same situation occurs for Wiedemann and Matteuci effects.
For magnetic, mechanical and electric phenomena in fluids see Magnetohydrodynamics and Electrohydrodynamics. | 7 | Magnetic Ordering |
Research has prompted many solutions to the increasing incidence of acid attacks in the world. Bangladesh, whose rates of attack have been decreasing, is a model for many countries, and they follow Bangladesh's lead in many legislative reforms. However, several reports highlighted the need for an increased, legal role of NGOs to offer rehabilitation support to acid survivors. Additionally, nearly all research stressed the need for stricter regulation of acid sales to combat this social issue. | 4 | Acids + Bases |
Although the metabolism of fructose and glucose share many of the same intermediate structures, they have very different metabolic fates in human metabolism. Fructose is metabolized almost completely in the liver in humans, and is directed toward replenishment of liver glycogen and triglyceride synthesis, while much of dietary glucose passes through the liver and goes to skeletal muscle, where it is metabolized to CO, HO and ATP, and to fat cells where it is metabolized primarily to glycerol phosphate for triglyceride synthesis as well as energy production. The products of fructose metabolism are liver glycogen and de novo lipogenesis of fatty acids and eventual synthesis of endogenous triglyceride. This synthesis can be divided into two main phases: The first phase is the synthesis of the trioses, dihydroxyacetone (DHAP) and glyceraldehyde; the second phase is the subsequent metabolism of these trioses either in the gluconeogenic pathway for glycogen replenishment and/or the complete metabolism in the fructolytic pathway to pyruvate, which enters the Krebs cycle, is converted to citrate and subsequently directed toward de novo synthesis of the free fatty acid palmitate. | 6 | Carbohydrates |
The significance of sources of FODMAPs varies through differences in dietary groups such as geography, ethnicity, and other factors. Commonly used FODMAPs comprise the following:
* oligosaccharides, including fructans and galactooligosaccharides
* disaccharides, including lactose
* monosaccharides, including fructose
* polyols, including sorbitol, xylitol, and mannitol | 6 | Carbohydrates |
Professor Reddi discovered that bone induction is a sequential multistep cascade involving chemotaxis, mitosis, and differentiation. Early studies in his laboratory at the University of Chicago and National Institutes of Health unraveled the sequence of events involved in bone matrix-induce bone morphogenesis. Using a battery of in vitro and in vivo bioassays for bone formation, a systematic study was undertaken in his laboratory to isolate and purify putative bone morphogenetic proteins. Reddi and colleagues were the first to identify BMPs as pleiotropic regulators, acting in a concentration dependent manner. They demonstrated first that BMPs bind the extracellular matrix, are present at the apical ectodermal ridge in the developing limb bud, are chemotactic for human monocytes, and have neurotropic potential. His laboratory pioneered the use of BMPs in regenerative orthopedics and dentistry. | 2 | Tissue Engineering |
In a handful of cases, a woman with vaginal aplasia has received a successful vagina transplant donated by her mother. The first such case is believed to have occurred in 1970, with no signs of rejection taking place after three years. In at least one case, a woman who received such a transplant was able to conceive and give birth. In 1981, a 12-year-old girl with vaginal aplasia received a vaginal wall implant from her mother. She became sexually active seven years later, without incident. At age 24, she conceived and carried a child to term. The child was born via cesarean section. | 2 | Tissue Engineering |
The helium hydrogen ion is isoelectronic with molecular hydrogen ().
Unlike the dihydrogen ion , the helium hydride ion has a permanent dipole moment, which makes its spectroscopic characterization easier. The calculated dipole moment of HeH is 2.26 or 2.84 D. The electron density in the ion is higher around the helium nucleus than the hydrogen. 80% of the electron charge is closer to the helium nucleus than to the hydrogen nucleus.
Spectroscopic detection is hampered, because one of its most prominent spectral lines, at 149.14 μm, coincides with a doublet of spectral lines belonging to the methylidyne radical ⫶CH.
The length of the covalent bond in the ion is 0.772 Å or 77.2 pm. | 4 | Acids + Bases |
Alpha-glucosidases are enzymes involved in breaking down complex carbohydrates such as starch and glycogen into their monomers.
They catalyze the cleavage of individual glucosyl residues from various glycoconjugates including alpha- or beta-linked polymers of glucose. This enzyme convert complex sugars into simpler ones. | 6 | Carbohydrates |
Vaginal aplasia is a rare medical condition in which the vagina does not form properly before birth. Those with the condition may have a partially formed vagina, or none at all. The condition is typically treated by reconstructive surgery. First a space is surgically created where the vagina would typically exist. Then tissue from another part of the body is harvested, molded into the shape of a vagina, and grafted into the vagina cavity. This technique has significant drawbacks. Typically, the implanted tissue does not function normally as a muscle, which can lead to low enjoyment of sexual intercourse. Additionally, stenosis (narrowing of the cavity) can occur over time. Most women require multiple surgeries before a satisfactory result is achieved. An alternative to traditional reconstructive surgery is transplantation. | 2 | Tissue Engineering |
In addition to converters using electrodes, pure inductive magnetic converters have also been proposed by Lev Artsimovich in 1963, then Alan Frederic Haught and his team from United Aircraft Research Laboratories in 1970, and Ralph Moir in 1977.
The magnetic compression-expansion direct energy converter is analogous to the internal combustion engine. As the hot plasma expands against a magnetic field, in a manner similar to hot gases expanding against a piston, part of the energy of the internal plasma is inductively converted to an electromagnetic coil, as an EMF (voltage) in the conductor.
This scheme is best used with pulsed devices, because the converter then works like a "magnetic four-stroke engine":
# Compression: A column of plasma is compressed by a magnetic field that acts like a piston.
# Thermonuclear burn: The compression heats the plasma to the thermonuclear ignition temperature.
# Expansion/Power: The expansion of fusion reaction products (charged particles) increases the plasma pressure and pushes the magnetic field outward. A voltage is induced and collected in the electromagnetic coil.
# Exhaust/Refuel: After expansion, the partially burned fuel is flushed out, and new fuel in the form of gas is introduced and ionized; and the cycle starts again.
In 1973, a team from Los Alamos and Argonne laboratories stated that the thermodynamic efficiency of the magnetic direct conversion cycle from alpha-particle energy to work is 62%. | 3 | Nuclear Fusion |
Active metabolism of glucose with production of bicarbonate has been demonstrated by Pettersson and Cohen.
Pettersson studies were on the metabolism of glucose and fatty acids by kidneys during 6 day hypothermic perfusion storage and he found that the kidneys consumed glucose at 4.4 μmol/g/day and fatty acids at 5.8 μmol/g/day. In Cohens study the best 8 day stored kidneys consumed glucose at the rate of 2.3 μmol/g/day and 4.9 μmol/g/day respectively which made it likely that they were using fatty acids at similar rates to Petterssons dogs' kidneys. The constancy of both the glucose consumption rate and the rate of bicarbonate production implied that no injury was affecting the glycolytic enzyme or carbonic anhydrase enzyme systems.
Lee showed that fatty acids were the preferred substrate of the rabbits kidney cortex at normothermic temperatures, and glucose the preferred substrate for the medullary cells which normally metabolise anaerobically. Abodeely showed that both fatty acids and glucose could be utilised by the outer medulla of the rabbits kidney but that glucose was used preferentially. At hypothermia the metabolic needs of the kidney are much reduced but measurable consumption of glucose, fatty acids and ketone bodies occurs. Horsburgh showed that lipid is utilised by hypothermic kidneys, with palmitate consumption being 0-15% of normal in the rat kidney cortex at 15 °C. Pettersson showed that, on a molar basis, glucose and fatty acids were metabolised by hypothermically perfused kidneys at about the same rates. The cortex of the hypothermic dog kidney was shown by Huang to lose lipid (35% loss of total lipid after 24 hours) unless oleate was added to the kidney perfusate. Huang commented that this loss could affect the structure of the cell and that the loss also suggested that the kidney was utilising fatty acid. In a later publication Huang showed that dog kidney cortex slices metabolised fatty acids, but not glucose, at 10 °C.
Even if the correct nutrients are provided, they may be lost by absorption into the tubing of the preservation system. Lee demonstrated that silicone rubber (a material used extensively in kidney preservation systems) absorbed 46% of a perfusate's oleic acid after 4 hours of perfusion. | 1 | Cryobiology |
Although there was already a main project (magnetic mirror) at the University of California, scientist W. R. Baker began research into the pinch effect at UCRL, Berkeley in 1952. Two years later, Stirling Colgate began research on shock-heating at UCRL, Livermore. | 3 | Nuclear Fusion |
H. Schwartz observed in 1955 that the decay of the tritium molecule = should generate the helium hydride ion with high probability.
In 1963, F. Cacace at the Sapienza University of Rome conceived the decay technique for preparing and studying organic radicals and carbenium ions. In a variant of that technique, exotic species like methanium are produced by reacting organic compounds with the that is produced by the decay of that is mixed with the desired reagents. Much of what we know about the chemistry of came through this technique. | 4 | Acids + Bases |
Staying dry and wearing proper clothing help to prevent hypothermia. Synthetic and wool fabrics are superior to cotton as they provide better insulation when wet and dry. Some synthetic fabrics, such as polypropylene and polyester, are used in clothing designed to wick perspiration away from the body, such as liner socks and moisture-wicking undergarments. Clothing should be loose fitting, as tight clothing reduces the circulation of warm blood. In planning outdoor activity, prepare appropriately for possible cold weather. Those who drink alcohol before or during outdoor activity should ensure at least one sober person is present responsible for safety.
Covering the head is effective, but no more effective than covering any other part of the body. While common folklore says that people lose most of their heat through their heads, heat loss from the head is no more significant than that from other uncovered parts of the body. However, heat loss from the head is significant in infants, whose head is larger relative to the rest of the body than in adults. Several studies have shown that for uncovered infants, lined hats significantly reduce heat loss and thermal stress. Children have a larger surface area per unit mass, and other things being equal should have one more layer of clothing than adults in similar conditions, and the time they spend in cold environments should be limited. However children are often more active than adults, and may generate more heat. In both adults and children, overexertion causes sweating and thus increases heat loss.
Building a shelter can aid survival where there is danger of death from exposure. Shelters can be constructed out of a variety of materials. Metal can conduct heat away from the occupants and is sometimes best avoided. The shelter should not be too big so body warmth stays near the occupants. Good ventilation is essential especially if a fire will be lit in the shelter. Fires should be put out before the occupants sleep to prevent carbon monoxide poisoning. People caught in very cold, snowy conditions can build an igloo or snow cave to shelter.
The United States Coast Guard promotes using life vests to protect against hypothermia through the 50/50/50 rule: If someone is in water for 50 minutes, they have a 50 percent better chance of survival if they are wearing a life jacket. A heat escape lessening position can be used to increase survival in cold water.
Babies should sleep at 16–20 °C (61–68 °F) and housebound people should be checked regularly to make sure the temperature of the home is at least 18 °C (64 °F). | 1 | Cryobiology |
Using a catalytic chemical reaction from titanium dioxide and UVC exposure, oxidation of organic matter converts pathogens, pollens, and mold spores into harmless inert byproducts. However, the reaction of titanium dioxide and UVC is not a straight path. Several hundreds of reactions occur prior to the inert byproducts stage and can hinder the resulting reaction creating formaldehyde, aldehyde, and other VOCs en route to a final stage. Thus, the use of titanium dioxide and UVC requires very specific parameters for a successful outcome. The cleansing mechanism of UV is a photochemical process. Contaminants in the indoor environment are almost entirely organic carbon-based compounds, which break down when exposed to high-intensity UV at 240 to 280 nm. Short-wave ultraviolet radiation can destroy DNA in living microorganisms. UVCs effectiveness is directly related to intensity and exposure time.
UV has also been shown to reduce gaseous contaminants such as carbon monoxide and VOCs. UV lamps radiating at 184 and 254 nm can remove low concentrations of hydrocarbons and carbon monoxide if the air is recycled between the room and the lamp chamber. This arrangement prevents the introduction of ozone into the treated air. Likewise, air may be treated by passing by a single UV source operating at 184 nm and passed over iron pentaoxide to remove the ozone produced by the UV lamp. | 8 | Ultraviolet Radiation |
In 2008, a California physician transferred 12 embryos to a woman who gave birth to octuplets (Suleman octuplets). This led to accusations that a doctor is willing to endanger the health and even life of people in order to gain money. Robert Winston, professor of fertility studies at Imperial College London, had called the industry "corrupt" and "greedy" stating that "one of the major problems facing us in healthcare is that IVF has become a massive commercial industry," and that "what has happened, of course, is that money is corrupting this whole technology", and accused authorities of failing to protect couples from exploitation: "The regulatory authority has done a consistently bad job. Its not prevented the exploitation of people, its not put out very good information to couples, it's not limited the number of unscientific treatments people have access to". The IVF industry has been described as a market-driven construction of health, medicine and the human body.
The industry has been accused of making unscientific claims, and distorting facts relating to infertility, in particular through widely exaggerated claims about how common infertility is in society, in an attempt to get as many couples as possible and as soon as possible to try treatments (rather than trying to conceive naturally for a longer time). This risks removing infertility from its social context and reducing the experience to a simple biological malfunction, which not only can be treated through bio-medical procedures, but should be treated by them. | 1 | Cryobiology |
The winnowing-fan (λίκνον [líknon], also meaning a "cradle") featured in the rites accorded Dionysus and in the Eleusinian Mysteries: "it was a simple agricultural implement taken over and mysticized by the religion of Dionysus," Jane Ellen Harrison remarked. Dionysus Liknites ("Dionysus of the winnowing fan") was wakened by the Dionysian women, in this instance called Thyiades, in a cave on Parnassus high above Delphi; the winnowing-fan links the god connected with the mystery religions to the agricultural cycle, but mortal Greek babies too were laid in a winnowing-fan. In Callimachus Hymn to Zeus, Adrasteia lays the infant Zeus in a golden líknon, her goat suckles him and he is given honey. In the Odyssey, the dead oracle Teiresias tells Odysseus to walk away from Ithaca with an oar until a wayfarer tells him it is a winnowing fan (i.e., until Odysseus has come so far from the sea that people dont recognize oars), and there to build a shrine to Poseidon. | 5 | Separation Processes |
Cryoneurolysis, also referred to as cryoanalgesia, is a medical procedure that temporarily blocks nerve conduction along peripheral nerve pathways. The procedure, which inserts a small probe to freeze the target nerve, can facilitate complete regeneration of the structure and function of the affected nerve. Cryoneurolysis has been used to treat a variety of painful conditions. | 1 | Cryobiology |
Insects most often use sugars or polyols as cryoprotectants. One species that uses cryoprotectant is Polistes exclamans (a wasp). In this species, the different levels of cryoprotectant can be used to distinguish between morphologies. | 1 | Cryobiology |
Tissue engineering aims to generate functional constructs which could replace or improve damaged or infected tissues or whole organs. Many of these constructs lead to infected tissue around the implant area. Coating these materials in amylopectin allows reduction in this infectious reaction. Since amylopectin is mainly used as a coating around these constructs in as it prevents following immune reactions. Since amylopectin is derived directly from a natural polysaccharide, it integrates well with tissues and cells. However, mechanical properties of amylopectin are not optimal due to its high level of crosslinking. This can be avoided by the formation of amylopectin fibers or by forming a nanocomposite with another more rigid polymer. | 6 | Carbohydrates |
In December 2020, the Chinese experimental nuclear fusion reactor HL-2M achieved its first plasma discharge. In May 2021, Experimental Advanced Superconducting Tokamak (EAST) announced a new world record for superheated plasma, sustaining a temperature of 120 M°C for 101 seconds and a peak of 160 M°C for 20 seconds. In December 2021 EAST set a new world record for high temperature (70 M°C) plasma of 1,056 seconds.
In 2020, Chevron Corporation announced an investment in start-up Zap Energy, co-founded by British entrepreneur and investor, Benj Conway, together with physicists Brian Nelson and Uri Shumlak from University of Washington. In 2021 the company raised $27.5 million in Series B funding led by Addition.
In 2021, the US DOE launched the INFUSE program, a public-private knowledge sharing initiative involving a PPPL, MIT Plasma Science and Fusion Center and Commonwealth Fusion Systems partnership, together with partnerships with TAE Technologies, Princeton Fusion Systems, and Tokamak Energy. In 2021, DOE's Fusion Energy Sciences Advisory Committee approved a strategic plan to guide fusion energy and plasma physics research that included a working power plant by 2040, similar to Canadian, Chinese, and U.K. efforts.
In January 2021, SuperOx announced the commercialization of a new superconducting wire, with more than 700 A/mm2 current capability.
TAE Technologies announced that its Norman device had sustained a temperature of about 60 million degrees C for 30 milliseconds, 8 and 10 times higher, respectively, than the company's previous devices. The duration was claimed to be limited by the power supply rather than the device.
In August 2021, the National Ignition Facility recorded a record-breaking 1.3 megajoules of energy created from fusion which is the first example of the Lawson criterion being surpassed in a laboratory.
In February 2022, JET sustained 11 MW and a Q value of 0.33 for over 5 seconds, outputting 59.7 megajoules, using a mix of deuterium and tritium for fuel. In March 2022 it was announced that Tokamak Energy achieved a record plasma temperature of 100 million kelvins, inside a commercial compact tokamak.
In October 2022, the Korea Superconducting Tokamak Advanced Research (KSTAR) reached a record plasma duration of 45 seconds, sustaining the high-temperature fusion plasma over the 100 million degrees Celsus based on the integrated real-time RMP control for ELM-less H-mode, i.e. fast ions regulated enhancement (FIRE) mode, machine learning algorithm, and 3D field optimization via an edge-localized RMP.
In December 2022, the NIF achieved the first scientific breakeven controlled fusion experiment, with an energy gain of 1.5.
In February 2024, the KSTAR tokamak set a new record (shot #34705) for the longest duration (102 seconds) of a magnetically confined plasma. The plasma was operated in ELM-less H-mode, with much better control of the error field than was possible previously. KSTAR also set a record (shot #34445) for the longest steady-state duration at a temperature of 100 million degrees Celsius (48 seconds). | 3 | Nuclear Fusion |
Germicidal UV for disinfection is most typically generated by a mercury-vapor lamp. Low-pressure mercury vapor has a strong emission line at 254 nm, which is within the range of wavelengths that demonstrate strong disinfection effect. The optimal wavelengths for disinfection are close to 260 nm.
Mercury vapor lamps may be categorized as either low-pressure (including amalgam) or medium-pressure lamps. Low-pressure UV lamps offer high efficiencies (approx. 35% UV-C) but lower power, typically 1 W/cm power density (power per unit of arc length). Amalgam UV lamps utilize an amalgam to control mercury pressure to allow operation at a somewhat higher temperature and power density. They operate at higher temperatures and have a lifetime of up to 16,000 hours. Their efficiency is slightly lower than that of traditional low-pressure lamps (approx. 33% UV-C output), and power density is approximately 2–3 W/cm. Medium-pressure UV lamps operate at much higher temperatures, up to about 800 degrees Celsius, and have a polychromatic output spectrum and a high radiation output but lower UV-C efficiency of 10% or less. Typical power density is 30 W/cm or greater.
Depending on the quartz glass used for the lamp body, low-pressure and amalgam UV emit radiation at 254 nm and also at 185 nm, which has chemical effects. UV radiation at 185 nm is used to generate ozone.
The UV lamps for water treatment consist of specialized low-pressure mercury-vapor lamps that produce ultraviolet radiation at 254 nm, or medium-pressure UV lamps that produce a polychromatic output from 200 nm to visible and infrared energy. The UV lamp never contacts the water; it is either housed in a quartz glass sleeve inside the water chamber or mounted externally to the water, which flows through the transparent UV tube. Water passing through the flow chamber is exposed to UV rays, which are absorbed by suspended solids, such as microorganisms and dirt, in the stream. | 8 | Ultraviolet Radiation |
UV water treatment devices can be used for well water and surface water disinfection. UV treatment compares favourably with other water disinfection systems in terms of cost, labour and the need for technically trained personnel for operation. Water chlorination treats larger organisms and offers residual disinfection, but these systems are expensive because they need special operator training and a steady supply of a potentially hazardous material. Finally, boiling of water is the most reliable treatment method but it demands labour and imposes a high economic cost. UV treatment is rapid and, in terms of primary energy use, approximately 20,000 times more efficient than boiling. | 8 | Ultraviolet Radiation |
The experimental determination of a value is commonly performed by means of a titration. A typical procedure would be as follows. A quantity of strong acid is added to a solution containing the acid or a salt of the acid, to the point where the compound is fully protonated. The solution is then titrated with a strong base
until only the deprotonated species, , remains in solution. At each point in the titration pH is measured using a glass electrode and a pH meter. The equilibrium constant is found by fitting calculated pH values to the observed values, using the method of least squares. | 4 | Acids + Bases |
When Deutsche Post of the GDR expanded automated mail processing in the 1980s, they did not use luminescent tagging, but used sideways illumination to identify the shadows of the stamp perforation in order to position mail items in cancelling and sorting machinery. Red light was used for this purpose, giving a good contrast to ordinary writing ink colours and enabling machine reading of postcodes. Some issues of Postal cards were printed entirely in orange to facilitate the latter process. However, the colours of the imprinted stamps was later changed to those of the usual definitives of the corresponding value, and simulated perforations were added around the stamp design to help locate the stamp position. | 0 | Luminescence |
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