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Arylalkylamine Substituted arylalkylamines are a group of chemical compounds. Two major classes of arylalkylamines include "indolylalkylamines" (e.g., tryptamines (a.k.a. indolylethylamines)) and "phenylalkylamines" (e.g., phenethylamines and amphetamines (a.k.a. phenylisopropylamines)), which consist of the monoamine neurotransmitters as well as clinically-used and recreationally-abused monoaminergic drugs, including psychostimulants, anorectics, wakefulness-promoting agents, bronchodilators, decongestants, antidepressants, entactogens, and psychedelics, among others. | https://en.wikipedia.org/wiki?curid=23727536 |
Optical sectioning is the process by which a suitably designed microscope can produce clear images of focal planes deep within a thick sample. This is used to reduce the need for thin sectioning using instruments such as the microtome. Many different techniques for optical sectioning are used and several microscopy techniques are specifically designed to improve the quality of optical sectioning. Good optical sectioning, often referred to as good depth or z resolution, is popular in modern microscopy as it allows the three-dimensional reconstruction of a sample from images captured at different focal planes. In an ideal microscope, only light from the focal plane would be allowed to reach the detector (typically an observer or a CCD) producing a clear image of the plane of the sample the microscope is focused on. Unfortunately a microscope is not this specific and light from sources outside the focal plane also reaches the detector; in a thick sample there may be a significant amount of material, and so spurious signal, between the focal plane and the objective lens. With no modification to the microscope, i.e. with a simple wide field light microscope, the quality of optical sectioning is governed by the same physics as the depth of field effect in photography. For a high numerical aperture lens, equivalent to a wide aperture, the depth of field is small (shallow focus) and gives good optical sectioning | https://en.wikipedia.org/wiki?curid=23728083 |
Optical sectioning High magnification objective lenses typically have higher numerical apertures (and so better optical sectioning) than low magnification objectives. Oil immersion objectives typically have even larger numerical apertures so improved optical sectioning. The resolution in the depth direction (the "z resolution") of a standard wide field microscope depends on the numerical aperture and the wavelength of the light and can be approximated as: formula_1 where λ is the wavelength, n the refractive index of the objective lens immersion media and NA the numerical aperture. In comparison, the lateral resolution can be approximated as: formula_2 Beyond increasing numerical aperture, there are few techniques available to improve optical sectioning in bright-field light microscopy. Most microscopes with oil immersion objectives are reaching the limits of numerical aperture possible due to refraction limits. Differential interference contrast (DIC) provides modest improvements to optical sectioning. In DIC the sample is effectively illuminated by two slightly offset light sources which then interfere to produce an image resulting from the phase differences of the two sources. As the offset in the light sources is small the only difference in phase results from the material close to the focal plane. In fluorescence microscopy objects out of the focal plane only interfere with the image if they are illuminated and fluoresce | https://en.wikipedia.org/wiki?curid=23728083 |
Optical sectioning This adds an extra way in which optical sectioning can be improved by making illumination specific to only the focal plane. Confocal microscopy uses a scanning point or points of light to illuminate the sample. In conjunction with a pinhole at a conjugate focal plane this acts to filter out light from sources outside the focal plane to improve optical sectioning. Lightsheet based fluorescence microscopy illuminates the sample with excitation light under an angle of 90° to the direction of observation, i.e. only the focal plane is illuminated using a laser that is only focused in one direction (lightsheet). This method effectively reduces out-of focus light and may in addition lead to a modest improvement in longitudinal resolution, compared to epi fluorescence microscopy. Dual and multi-photon excitation techniques take advantage of the fact that fluorophores can be excited not just by a single photon of the correct energy but also by multiple photons, which together provide the correct energy. The additional "concentration"-dependent effect of requiring multiple photons to simultaneously interact with a fluorophore gives stimulation only very close to the focal plane. These techniques are normally used in conjunction with confocal microscopy. Further improvements in optical sectioning are under active development, these principally work through methods to circumvent the diffraction limit of light | https://en.wikipedia.org/wiki?curid=23728083 |
Optical sectioning Examples include single photon interferometry through two objective lenses to give extremely accurate depth information about a single fluorophore and three-dimensional structured illumination microscopy. The optical sectioning of normal wide field microscopes can be improved significantly by deconvolution, an image processing technique to remove blur from the image according to a measured or calculated point spread function. can be enhanced by the use of clearing agents possessing a high refractive index (>1.4) such as Benzyl-Alcohol/Benzyl Benzoate (BABB) or Benzyl-ether which render specimens transparent and therefore allow for observation of internal structures. is underdeveloped in non-light microscopes. X-ray and electron microscopes typically have a large depth of field (poor optical sectioning), and thus thin sectioning of samples is still widely used. Although similar physics guides the focusing process, Scanning probe microscopes and scanning electron microscopes are not typically discussed in the context of optical sectioning as these microscopes only interact with the surface of the sample. Total internal reflection microscopy is a fluorescent microscopy technique, which intentionally restricts observation to either the top or bottom surfaces of a sample, but with extremely high depth resolution. 3D imaging using a combination of focal sectioning and tilting has been demonstrated theoretically and experimentally in order to provide exceptional 3D resolution over large fields of view | https://en.wikipedia.org/wiki?curid=23728083 |
Optical sectioning The primary alternatives to optical sectioning are: | https://en.wikipedia.org/wiki?curid=23728083 |
Aminopropane may refer to: | https://en.wikipedia.org/wiki?curid=23728830 |
C7H10O5 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23729513 |
C6H8O3 The molecular formula CHO (molar mass: 128.13 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23729581 |
C7H19N3 The molecular formula CHN may refer to: | https://en.wikipedia.org/wiki?curid=23729594 |
C30H50 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23729622 |
C21H22N2O2 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23729651 |
C6H7NO3S The molecular formula CHNOS (molar mass: 173.190 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23729712 |
Upstream open reading frame An upstream open reading frame (uORF) is an open reading frame (ORF) within the 5' untranslated region (5'UTR) of an mRNA. uORFs can regulate eukaryotic gene expression. Translation of the uORF typically inhibits downstream expression of the primary ORF. In bacteria, uORFs are called leader peptides and were originally discovered on the basis of their impact on the regulation of genes involved in the synthesis or transport of amino acids. Approximately 50% of human genes contain uORFs in their 5'UTR, and when present, these cause reductions in protein expression. Human peptides derived from translated uORFs can be detected from cellular material with a mass spectrometer. | https://en.wikipedia.org/wiki?curid=23732455 |
Secondary spill containment is the containment of hazardous liquids in order to prevent pollution of soil and water. Common techniques include the use of spill berms to contain oil-filled equipment, fuel tanks, truck washing decks, or any other places or items that may leak hazardous liquids. involves the sequestration of hazardous waste to prevent the contamination of local soils and water. United States Environmental Protection Agency (EPA) Spill Prevention, Control, and Countermeasure (SPCC) guidelines require that facilities that store large quantities of petroleum (products) must have a plan in place to contain a spill. The purpose of the SPCC rule is to establish requirements for facilities to prevent a discharge of oil into navigable waters or adjoining shorelines. Within the electric utility industry, oil-filled transformers are often in need of secondary containment. Outdated secondary containment techniques such as concrete catch-basins are quickly losing ground to solutions that offer more cost-effective cleanup in case of a spill or leak. One example of a more cost-effective method involves placing a geotextile boom filled with oil solidifying polymers around a transformer. These geotextile barriers allow for flow of water, but completely solidify oil in the event of a leak and effectively seal the spill | https://en.wikipedia.org/wiki?curid=23733801 |
Secondary spill containment Many electrical utility companies are switching to this method because it saves them significant amounts of money when a spill occurs, because there is no need to employ vac-trucks afterwards to clean up a spill inside a catch-basin. Portable containment berms are essentially a basin that can catch many different types of hazardous liquids and chemicals. They are a form of secondary spill containment useful for containing mobile equipment such as oil drums, trucks, tankers and trailers. Unlike geotextile berms, portable berms usually do not solidify oil. Many companies involved in fracking use spill containment berms to capture contaminated water that is a by-product of the operation. Each well site has multiple trucks that transport water used in deep well drilling procedure. | https://en.wikipedia.org/wiki?curid=23733801 |
Trojan wave packet A trojan wave packet is a wave packet that is nonstationary and nonspreading. It is part of an artificially created system that consists of a nucleus and one or more electron wave packets, and that is highly excited under a continuous electromagnetic field. The strong, polarized electromagnetic field, holds or "traps" each electron wave packet in an intentionally selected orbit (energy shell). They derive their names from the trojan asteroids in the Sun–Jupiter system. Trojan asteroids orbit around the Sun in Jupiter's orbit at its Lagrangian equilibrium points L4 and L5, where they are phase-locked and protected from collision with each other, and this phenomenon is analogous to the way the wave packet is held together. The concept of the is derived from a flourishing area of physics which manipulates atoms and ions at the atomic level creating ion traps. Ion traps allow the manipulation of atoms and are used to create new states of matter including ionic liquids, Wigner crystals and Bose–Einstein condensates. This ability to manipulate the quantum properties directly is key to the real life development of applicable nanodevices such as quantum dots and microchip traps. In 2004 it was shown that it is possible to create a trap which is actually a single atom. Within the atom, the behavior of an electron can be manipulated. During experiments in 2004 using lithium atoms in an excited state, researchers were able to localize an electron in a classical orbit for 15,000 orbits (900 ns) | https://en.wikipedia.org/wiki?curid=23735926 |
Trojan wave packet It was neither spreading nor dispersing. This "classical atom" was synthesized by "tethering" the electron using a microwave field to which its motion is phase locked. The phase lock of the electrons in this unique atomic system is, as mentioned above, analogous to the phase locked asteroids of Jupiter's orbit. The techniques explored in this experiment are a solution to a problem that dates back to 1926. Physicists at that time realized that any initially localized wave packet will inevitably spread around the orbit of the electrons. Physicist noticed that "the wave equation is dispersive for the atomic Coulomb potential." In the 1980s several groups of researchers proved this to be true. The wave packets spread all the way around the orbits and coherently interfered with themselves. Recently the real world innovation realized with experiments such as Trojan wave packets, is localizing the wave packets, i.e., with no dispersion. Applying a polarized circular EM field, at microwave frequencies, synchronized with an electron wave packet, intentionally keeps the electron wave packets in a Lagrange type orbit. The experiments built on previous work with lithium atoms in an excited state. These are atoms, which respond sensitively to electric and magnetic fields, have decay periods that are relatively prolonged, and electrons, which for all intents and purposes actually operate in classical orbits | https://en.wikipedia.org/wiki?curid=23735926 |
Trojan wave packet The sensitivity to electric and magnetic fields is important because this allows control and response by the polarized microwave field. The next logical step is to attempt to move from single electron wave packets to more than one electron wave packet. This had already been accomplished in barium atoms, with two electron wave packets. These two were localized. However, eventually, these created dispersion after colliding near the nucleus. Another technique employed a nondispersive pair of electrons, but one of these had to have a localized orbit close to the nucleus. The nondispersive two-electron Trojan wave packets demonstration changes all that. These are the next step analogue of the one electron Trojan wave packets – and designed for excited helium atoms. As of July 2005, atoms with coherent, stable two-electron, nondispersing wave packets had been created. These are excited helium-like atoms, or quantum dot helium (in solid-state applications), and are atomic (quantum) analogues to the three body problem of Newton's classical physics, which includes today's astrophysics. In tandem, circularly polarized electromagnetic and magnetic fields stabilize the two electron configuration in the helium atom or the quantum dot helium (with impurity center). The stability is maintained over a broad spectrum, and because of this, the configuration of two electron wave packets is considered to be truly nondispersive | https://en.wikipedia.org/wiki?curid=23735926 |
Trojan wave packet For example, with the quantum dot helium, configured for confining electrons in two spatial dimensions, there now exists a variety of trojan wave packet configurations with two electrons, and as of 2005, only one in three dimensions. In 2012 an essential experimental step was undertaken not only generating but locking the Trojan wavepackets on adiabatically changed frequency and expanding the atoms as once predicted by Kalinski and Eberly. It will allow to create two electron Langmuir Trojan wave packets in Helium by the sequential excitation in adiabatic Stark field able to produce the circular one-electron aureola over first and then put the second electron in similar state. | https://en.wikipedia.org/wiki?curid=23735926 |
Dulong–Petit law The Dulong–Petit law, a thermodynamic law proposed in 1819 by French physicists Pierre Louis Dulong and Alexis Thérèse Petit, states the classical expression for the molar specific heat capacity of certain chemical elements. Experimentally the two scientists had found that the heat capacity per weight (the mass-specific heat capacity) for a number of elements was close to a constant value, "after" it had been multiplied by a number representing the presumed relative atomic weight of the element. These atomic weights had shortly before been suggested by John Dalton and modified by Jacob Berzelius. In modern terms, Dulong and Petit found that the heat capacity of a mole of many solid elements is about 3"R", where "R" is the modern constant called the universal gas constant. Dulong and Petit were unaware of the relationship with "R", since this constant had not yet been defined from the later kinetic theory of gases. The value of 3"R" is about 25 joules per kelvin, and Dulong and Petit essentially found that this was the heat capacity of certain solid elements per mole of atoms they contained. The modern theory of the heat capacity of solids states that it is due to lattice vibrations in the solid and was first derived in crude form from this assumption by Albert Einstein in 1907. The Einstein solid model thus gave for the first time a reason why the should be stated in terms of the classical heat capacities for gases | https://en.wikipedia.org/wiki?curid=23736226 |
Dulong–Petit law An equivalent statement of the in modern terms is that, regardless of the nature of the substance, the specific heat capacity "c" of a solid element (measured in joule per kelvin per kilogram) is equal to 3"R"/"M", where "R" is the gas constant (measured in joule per kelvin per mole) and "M" is the molar mass (measured in kilogram per mole). Thus, the heat capacity per mole of many elements is 3"R". The initial form of the was: where "K" is a constant which we know today is about 3"R". In modern terms the mass "m" of the sample divided by molar mass "M" gives the number of moles "n". Therefore, using uppercase "C" for the full heat capacity (in joule per kelvin), we have: or Therefore, the heat capacity of most solid crystalline substances is 3"R" per mole of substance. Dulong and Petit did not state their law in terms of the gas constant "R" (which was not then known). Instead, they measured the values of heat capacities (per weight) of substances and found them smaller for substances of greater atomic weight as inferred by Dalton and other early atomists. Dulong and Petit then found that when multiplied by these atomic weights, the value for the heat capacity per mole was nearly constant, and equal to a value which was later recognized to be 3"R". In other modern terminology, the dimensionless heat capacity ("C"/"NR") is equal to 3. The law can also be written as a function of the total number of atoms "N" in the sample: where "k" is Boltzmann constant | https://en.wikipedia.org/wiki?curid=23736226 |
Dulong–Petit law Despite its simplicity, offers fairly good prediction for the heat capacity of many elementary solids with relatively simple crystal structure at high temperatures. This agreement is because in the classical statistical theory of Ludwig Boltzmann, the heat capacity of solids approaches a maximum of 3"R" per mole of atoms because full vibrational-mode degrees of freedom amount to 3 degrees of freedom per atom, each corresponding to a quadratic kinetic energy term and a quadratic potential energy term. By the equipartition theorem, the average of each quadratic term is "k""T", or "RT" per mole (see derivation below). Multiplied by 3 degrees of freedom and the two terms per degree of freedom, this amounts to 3"R" per mole heat capacity. The fails at room temperatures for light atoms bonded strongly to each other, such as in metallic beryllium and in carbon as diamond. Here, it predicts higher heat capacities than are actually found, with the difference due to higher-energy vibrational modes not being populated at room temperatures in these substances. In the very low (cryogenic) temperature region, where the quantum mechanical nature of energy storage in all solids manifests itself with larger and larger effect, the law fails for all substances. For crystals under such conditions, the Debye model, an extension of the Einstein theory that accounts for statistical distributions in atomic vibration when there are lower amounts of energy to distribute, works well | https://en.wikipedia.org/wiki?curid=23736226 |
Dulong–Petit law A system of vibrations in a crystalline solid lattice can be modelled as an Einstein solid, i.e. by considering "N" quantum harmonic oscillator potentials along each degree of freedom. Then, the free energy of the system can be written as where the index "α" sums over all the degrees of freedom. In the 1907 Einstein model (as opposed to the later Debye model) we consider only the high-energy limit: Then and we have Define "geometric mean frequency" by where "g" measures the total number of spatial degrees of freedom of the system. Thus we have Using energy we have This gives heat capacity at constant volume which is independent of the temperature. For another more precise derivation, see Debye model. | https://en.wikipedia.org/wiki?curid=23736226 |
C8H6O4 C8H6O4 | https://en.wikipedia.org/wiki?curid=23739454 |
C19H25NO4 The molecular formula CHNO (molar mass: 331.412 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23739596 |
C10H14N2O5 The molecular formula CHNO (molar mass: 242.229 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23740130 |
C29H50O2 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23740207 |
C6H13NO5 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23741687 |
C12H19NO3 The molecular formula CHNO (molar mass : 225.28 g/mol, exact mass : 225.136493) may refer to: | https://en.wikipedia.org/wiki?curid=23741841 |
C3H9O3P The molecular formula CHOP (molar mass: 124.076 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23741851 |
C18H15N The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23742402 |
C18H12 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=23742447 |
C8H15N The molecular formula CHN may refer to: | https://en.wikipedia.org/wiki?curid=23742530 |
C11H12N2O2 The molecular formula CHNO (molar mass : 204.22 g/mol, exact mass : 204.089878) may refer to: | https://en.wikipedia.org/wiki?curid=23742583 |
C9H11NO3 The molecular formula CHNO (molar mass: 181.18 g/mol, exact mass: 181.073893) may refer to: | https://en.wikipedia.org/wiki?curid=23742612 |
C9H6O3 The molecular formula CHO (molar mass : 162.14 g/mol, exact mass : 162.031694) may refer to : | https://en.wikipedia.org/wiki?curid=23742625 |
C9H12N2O6 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23742708 |
C18H16O7 The molecular formula CHO (molar mass: 344.31 g/mol, exact mass: 344.089603) may refer to: | https://en.wikipedia.org/wiki?curid=23742719 |
Gold (hieroglyph) The Egyptian hieroglyph representing gold (𓋞 Gardiner S12), phonetic value "nb", is important due to its use in the Horus-of-Gold name, one of the Fivefold Titulary names of the Egyptian pharaoh. In its determinative usage, it identifies any precious metal, The hieroglyph represents a large gold and pearl necklace. Old Kingdom scenes show dwarfs metalworking the gold, and "stringing the pearls of gold". Three variants of the gold hieroglyph are ligatured with another hieroglyph: The meaning of this particular title has been disputed. One belief is that it represents the triumph of Horus over his uncle Seth, as the symbol for gold can be taken to mean that Horus was "superior to his foes". Gold also was strongly associated in the ancient Egyptian mind with eternity, so this may have been intended to convey the pharaoh's eternal Horus name. The combination of the Horus falcon and the gold hieroglyph is frequently found on Ancient Egyptian pectorals (see image). In the Old Egyptian Palermo Stone inscription (late 24th or early 23rd century BC), the hieroglyph is used in the phrases "first counting of gold" and "collar of gold". One of the few coins minted for ancient Egypt is the gold stater, issued during the 30th Dynasty. The reverse of the gold stater shows a horse reared up on its hind legs. The obverse has the two hieroglyphs for "nfr" and "nb": ""Perfect gold"", or a common-era term: " 'Fine'-gold", (""Beautiful Gold"") | https://en.wikipedia.org/wiki?curid=23743517 |
Gold (hieroglyph) The reverse, horse iconography is referenced because of the "beauty", and uniqueness of the horse species. | https://en.wikipedia.org/wiki?curid=23743517 |
Fukuyama reduction The is an organic reaction and an organic reduction in which a thioester is reduced to an aldehyde by a silyl hydride in presence of a catalytic amount of palladium. This reaction was invented in 1990 by Tohru Fukuyama. In the original scope of the reaction the silyl hydride was triethylsilane and the catalyst palladium on carbon: Fukuyama reductions are used for the conversion of carboxylic acids (as thioester precursor) to aldehydes which is considered a difficult procedure because of the ease of secondary reduction to an alcohol. The basic reaction mechanism for this reaction takes place as a catalytic cycle: In a variation of the the core BODIPY molecule has been synthesized from the SMe-substituted derivative: In the related Fukuyama coupling the hydride is replaced by a carbon nucleophile. | https://en.wikipedia.org/wiki?curid=23743967 |
Iodine in biology Iodine is an essential trace element in biological systems. It has the distinction of being the heaviest element commonly needed by living organisms as well as the second-heaviest known to be used by any form of life (only tungsten, a component of a few bacterial enzymes, has a higher atomic number and atomic weight). It is a component of biochemical pathways in organisms from all biological kingdoms, suggesting its fundamental significance throughout the evolutionary history of life. Iodine is critical to the proper functioning of the vertebrate endocrine system, and plays smaller roles in numerous other organs, including those of the digestive and reproductive systems. An adequate intake of iodine-containing compounds is important at all stages of development, especially during the fetal and neonatal periods, and diets deficient in iodine can present serious consequences for growth and metabolism. In vertebrate biology, iodine's primary function is as a constituent of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3). These molecules are made from addition-condensation products of the amino acid tyrosine, and are stored prior to release in an iodine-containing protein called thyroglobulin. T4 and T3 contain four and three atoms of iodine per molecule, respectively; iodine accounts for 65% of the molecular weight of T4 and 59% of T3 | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology The thyroid gland actively absorbs iodine from the blood to produce and release these hormones into the blood, actions which are regulated by a second hormone, called thyroid-stimulating hormone (TSH), which is produced by the pituitary gland. Thyroid hormones are phylogenetically very old molecules which are synthesized by most multicellular organisms, and which even have some effect on unicellular organisms. Thyroid hormones play a fundamental role in biology, acting upon gene transcription mechanisms to regulate the basal metabolic rate. T3 acts on small intestine cells and adipocytes to increase carbohydrate absorption and fatty acid release, respectively. A deficiency of thyroid hormones can reduce basal metabolic rate up to 50%, while an excessive production of thyroid hormones can increase the basal metabolic rate by 100%. T4 acts largely as a precursor to T3, which is (with minor exceptions) the biologically active hormone. Via the thyroid hormones, iodine has a nutritional relationship with selenium. A family of selenium-dependent enzymes called deiodinases converts T4 to T3 (the active hormone) by removing an iodine atom from the outer tyrosine ring. These enzymes also convert T4 to reverse T3 (rT3) by removing an inner ring iodine atom, and also convert T3 to 3,3'-Diiodothyronine (T2) by removing an inner ring atom. Both of the latter products are inactivated hormones which have essentially no biological effects and are quickly prepared for disposal | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology A family of non-selenium-dependent enzymes then further deiodinates the products of these reactions. Selenium also plays a very important role in the production of glutathione, the body's most powerful antioxidant. During the production of the thyroid hormones, hydrogen peroxide is produced in large quantities, and therefore high iodine in the absence of selenium can destroy the thyroid gland (often described as a sore throat feeling); the peroxides are neutralized through the production of glutathione from selenium. In turn, an excess of selenium increases demand for iodine, and deficiency will result when a diet is high in selenium and low in iodine. The human body contains about 15–20 mg of iodine, mostly concentrated in thyroid tissue (70–80%). Extra-thyroidal iodine exists in several other organs, including the mammary glands, eyes, gastric mucosa, cervix, cerebrospinal fluid, arterial walls, ovary and salivary glands. In the cells of these tissues the iodide ion (I) enters directly by the sodium-iodide symporter (NIS). Different tissue responses for iodine and iodide occur in the mammary glands and the thyroid gland of rats. The role of iodine in mammary tissue is related to fetal and neonatal development, but its role in the other tissues is not well known. It has been shown to act as an antioxidant and antiproliferant in various tissues that can uptake iodine. Molecular iodine (I) has been shown to have a suppressive effect on benign and cancerous neoplasias. The U.S | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology Food and Nutrition Board and Institute of Medicine recommended daily allowance of iodine ranges from 150 micrograms per day for adult humans to 290 micrograms per day for lactating mothers. However, the thyroid gland needs no more than 70 micrograms per day to synthesize the requisite daily amounts of T4 and T3. The higher recommended daily allowance levels of iodine seem necessary for optimal function of a number of other body systems, including lactating breasts, gastric mucosa, salivary glands, oral mucosa, arterial walls, thymus, epidermis, choroid plexus and cerebrospinal fluid, among others. Iodine and thyroxine have also been shown to stimulate the spectacular apoptosis of the cells of the larval gills, tail and fins during metamorphosis in amphibians, as well as the transformation of their nervous system from that of the aquatic, herbivorous tadpole into that of the terrestrial, carnivorous adult. The frog species "Xenopus laevis" has proven to be an ideal model organism for experimental study of the mechanisms of apoptosis and the role of iodine in developmental biology. Moreover, iodine can add to double bonds of docosahexaenoic acid and arachidonic acid of cellular membranes, making them less reactive to free oxygen radicals. The U.S. Institute of Medicine (IOM) updated Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for iodine in 2000 | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology For people age 14 and up, the iodine RDA is 150 μg/day; the RDA for pregnant women is 220 μg/day and the RDA during lactation is 290 μg/day. For children 1–8 years, the RDA is 90 μg/day; for children 8–13 years, 130 μg/day. As a safety consideration, the IOM sets tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. The UL for iodine for adults is 1,100 μg/day. This UL was assessed by analyzing the effect of supplementation on thyroid-stimulating hormone. Collectively, the EARs, RDAs, AIs and ULs are referred to as Dietary Reference Intakes (DRIs). The European Food Safety Authority (EFSA) refers to the collective set of information as Dietary Reference Values, with Population Reference Intake (PRI) instead of RDA, and Average Requirement instead of EAR; AI and UL are defined the same as in the United States. For women and men ages 18 and older, the PRI for iodine is set at 150 μg/day; the PRI during pregnancy or lactation is 200 μg/day. For children ages 1–17 years, the PRI increases with age from 90 to 130 μg/day. These PRIs are comparable to the U.S. RDAs with the exception of that for lactation. The EFSA reviewed the same safety question and set its adult UL at 600 μg/day, which is a bit more than half the U.S. value. Notably, Japan reduced its adult iodine UL from 3,000 to 2,200 µg/day in 2010, but then increased it back to 3,000 µg/day in 2015. For U.S | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology food and dietary supplement labeling purposes, the amount in a serving is expressed as a percent of Daily Value (%DV). For iodine specifically, 100% of the Daily Value is considered 150 μg, and this figure remained at 150 μg in the May 27, 2016 revision. A table of the old and new adult Daily Values is provided at Reference Daily Intake. The original deadline to be in compliance was July 28, 2018, but on September 29, 2017, the FDA released a proposed rule that extended the deadline to January 1, 2020 for large companies and January 1, 2021 for small companies. As of 2000, the median observed intake of iodine from food in the United States was 240 to 300 μg/day for men and 190 to 210 μg/day for women. In Japan, consumption is much higher due to the frequent consumption of seaweed or kombu kelp. The average daily intake in Japan ranges from 1,000 to 3,000 μg/day; previous estimates suggested an average intake as high as 13,000 μg/day. Natural sources of iodine include many marine organisms, such as kelp and certain seafood products, as well as plants grown on iodine-rich soil. Iodized salt is fortified with iodine. According to a Food Fortification Initiative 2016 report, 130 countries have mandatory iodine fortification of salt and an additional 10 have voluntary fortification. Worldwide, iodine deficiency affects two billion people and is the leading preventable cause of mental retardation | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology Mental disability is a result which occurs primarily when babies or small children are rendered hypothyroidic by a lack of dietary iodine (new hypothyroidism in adults may cause temporary mental slowing, but not permanent damage). In areas where there is little iodine in the diet, typically remote inland areas and semi-arid equatorial climates where no marine foods are eaten, iodine deficiency also gives rise to hypothyroidism, the most serious symptoms of which are epidemic goitre (swelling of the thyroid gland), extreme fatigue, mental slowing, depression, weight gain, and low basal body temperatures. The addition of iodine to table salt (so-called iodized salt) has largely eliminated the most severe consequences of iodine deficiency in wealthier nations, but deficiency remains a serious public health problem in the developing world. Iodine deficiency is also a problem in certain areas of Europe; in Germany, an estimated one billion dollars in healthcare costs is spent each year in combating and treating iodine deficiency. Source: <onlyinclude> Elemental iodine is an oxidizing irritant, and direct contact with skin can cause lesions, so iodine crystals should be handled with care. Solutions with high elemental iodine concentration such as tincture of iodine are capable of causing tissue damage if use for cleaning and antisepsis is prolonged | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology Although elemental iodine is used in the formulation of Lugol's solution, a common medical disinfectant, it becomes triiodide upon reacting with the potassium iodide used in the solution and is therefore non-toxic. Only a small amount of elemental iodine will dissolve in water, and adding potassium iodide allows a much larger amount of elemental iodine to dissolve through the reaction of I2-I3. This allows Lugol's iodine to be produced in strengths varying from 2% to 15% iodine. Elemental iodine (I) is poisonous if taken orally in large amounts; 2–3 grams is a lethal dose for an adult human. Potassium iodide, on the other hand, has a median lethal dose (LD) that is relatively high in several other animals: in rabbits, it is 10 g/kg; in rats, 14 g/kg, and in mice, 22 g/kg. The tolerable upper intake level for iodine as established by the Food and Nutrition Board is 1,100 µg/day for adults. The safe upper limit of consumption set by the Ministry of Health, Labor and Welfare in Japan is 3,000 µg/day. The biological half-life of iodine differs between the various organs of the body, from 100 days in the thyroid, to 14 days in the kidneys and spleen, to 7 days in the reproductive organs. Typically the daily urinary elimination rate ranges from 100 to 200 µg/L in humans. However, the Japanese diet, high in iodine-rich kelp, contains 1,000 to 3,000 µg of iodine per day, and research indicates the body can readily eliminate excess iodine that is not needed for thyroid hormone production | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology The literature reports as much as 30,000 µg/L (30 mg/L) of iodine being safely excreted in the urine in a single day, with levels returning to the standard range in a couple of days, depending on seaweed intake. One study concluded the range of total body iodine content in males was 12.1 mg to 25.3 mg, with a mean of 14.6 mg. It is presumed that once thyroid-stimulating hormone is suppressed, the body simply eliminates excess iodine, and as a result, long-term supplementation with high doses of iodine has no additional effect once the body is replete with enough iodine. It is unknown if the thyroid gland is the rate-limiting factor in generating thyroid hormone from iodine and tyrosine, but assuming it is not, a short-term loading dose of one or two weeks at the tolerable upper intake level may quickly restore thyroid function in iodine-deficient patients. Iodine vapor is very irritating to the eye, to mucous membranes, and in the respiratory tract. Concentration of iodine in the air should not exceed 1 mg/m (eight-hour time-weighted average). When mixed with ammonia and water, elemental iodine forms nitrogen triiodide, which is extremely shock-sensitive and can explode unexpectedly. Excessive iodine intake presents symptoms similar to those of iodine deficiency. Commonly encountered symptoms are abnormal growth of the thyroid gland and disorders in functioning, as well as in growth of the organism as a whole | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology Iodide toxicity is similar to (but not the same as) toxicity to ions of the other halogens, such as bromides or fluorides. Excess bromine and fluorine can prevent successful iodine uptake, storage and use in organisms, as both elements can selectively replace iodine biochemically. Excess iodine may also be more cytotoxic in combination with selenium deficiency. Iodine supplementation in selenium-deficient populations is theoretically problematic, partly for this reason. Selenocysteine (abbreviated as Sec or U, in older publications also as Se-Cys) is the 21st proteinogenic amino acid, and is the root of iodide ion toxicity when there is a simultaneous insufficiency of biologically available selenium. Selenocysteine exists naturally in all kingdoms of life as a building block of selenoproteins. Some people develop a hypersensitivity to compounds of iodine but there are no known cases of people being directly allergic to elemental iodine itself. Notable sensitivity reactions that have been observed in humans include: Medical use of iodine compounds (i.e. as a contrast agent) can cause anaphylactic shock in highly sensitive patients, presumably due to sensitivity to the chemical carrier. Cases of sensitivity to iodine compounds should not be formally classified as iodine allergies, as this perpetuates the erroneous belief that it is the iodine to which patients react, rather than to the specific allergen | https://en.wikipedia.org/wiki?curid=23747793 |
Iodine in biology Sensitivity to iodine-containing compounds is rare but has a considerable effect given the extremely widespread use of iodine-based contrast media. | https://en.wikipedia.org/wiki?curid=23747793 |
C8H8O3 The molecular formula CHO (molar mass: 152.15 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23749838 |
C17H27NO2 The molecular formula CHNO (molar mass : 277.40 g/mol, exact mass : 277.204179) may refer to: | https://en.wikipedia.org/wiki?curid=23749854 |
C63H88CoN14O14P The molecular formula CHCoNOP may refer to: | https://en.wikipedia.org/wiki?curid=23749958 |
C19H16O4 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23750047 |
C13H8O2 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=23750071 |
C21H26N2O3 The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=23750190 |
Combined Development Agency The (CDA), originally the Combined Development Trust (CDT), was a defense purchasing authority established in 1944 by the governments of the United States and the United Kingdom. Its role was to ensure adequate supplies of uranium for the respective countries weapons development programs. The agency initiated a range of incentives to several countries to encourage exploration and a fast buildup of mineral reserves. The main countries targeted for the programs were the US, Canada, South Africa, and to a limited extent Australia. The countries tried to monopolize on the resources of the territories they owned or that had hardly any claim. The Belgian Congo was an example of the third world place that was used for its resources. In Australia, uranium ore from a number of mines was processed at the purpose built Port Pirie Uranium Treatment Complex which operated under contract to the CDA by the Government of South Australia between 1955 and 1962. General Leslie Groves was a United States General that was put in charge of assembling and maintaining the Manhattan Project. He was a major campaigner for the creation of the CDT because he saw the importance of not only obtaining an adequate amount of uranium to complete the needs of the Manhattan Project, but also to attempt to obtain the uranium so that the Soviet Union would have less access. The entire world's stockpile of uranium was unknown, but a joint effort was a good start to securing access to the most uranium possible | https://en.wikipedia.org/wiki?curid=23751078 |
Combined Development Agency He first created a program, Murray Hill Area Project, that’s main goal was to seek locations of uranium ore and thorium ore based on reports from mostly foreign documents. He found that protecting the thorium could prove just as important because it could be converted into uranium. This meant that finding the locations was only half the battle and funneled money into the purchase of the varies mineral rights. | https://en.wikipedia.org/wiki?curid=23751078 |
Thiirene is a sulfur heterocycle. | https://en.wikipedia.org/wiki?curid=23755701 |
Severe plastic deformation (SPD) is a generic term describing a group of metalworking techniques involving very large strains typically involving a complex stress state or high shear, resulting in a high defect density and equiaxed "ultrafine" grain (UFG) size (d < 500 nm) or nanocrystalline (NC) structure (d < 100 nm). The development of the principles underlying SPD techniques goes back to the pioneering work of P.W. Bridgman at Harvard University in the 1930s. This work concerned the effects on solids of combining large hydrostatic pressures with concurrent shear deformation and it led to the award of the Nobel Prize in Physics in 1946. Very successful early implementations of these principles, described in more detail below, are the processes of equal-channel angular pressing (ECAP) developed by V.M. Segal and co-workers in Minsk in the 1970s and high-pressure torsion, derived from Bridgman's work, but not widely developed until the 1980s at the Russian Institute of Metals Physics in modern-day Yekaterinburg. Some definitions of SPD describe it as a process in which high strain is applied without any significant change in the dimensions of the workpiece, resulting in a large hydrostatic pressure component. However, the mechanisms that lead to grain refinement in SPD are the same as those originally developed for mechanical alloying, a powder process that has been characterized as "severe plastic deformation" by authors as early as 1983 | https://en.wikipedia.org/wiki?curid=23756855 |
Severe plastic deformation Additionally, some more recent processes such as asymmetric rolling, do result in a change in the dimensions of the workpiece, while still producing an ultrafine grain structure. The principles behind SPD have even been applied to surface treatments. Equal channel angular extrusion (ECAE, sometimes called Equal channel angular pressing, ECAP) was developed in the 1970s. In this process, a metal billet is pressed through an angled (typically 90 degrees) channel. To achieve optimal results, the process may be repeated several times, changing the orientation of the billet with each pass. This produces a uniform shear throughout the bulk of the material. High pressure torsion (HPT) can be traced back to the experiments that won Percy Bridgman the 1946 Nobel Prize in Physics, though its use in metal processing is considerably more recent. In this method, a disk of the material to be strained is placed between 2 anvils. A large compressive stress (typically several gigapascals) is applied, while one anvil is rotated to create a torsion force. HPT can be performed unconstrained, in which the material is free to flow outward, fully constrained, or to some degree between in which outward flow is allowed, but limited. In accumulative roll bonding (ARB), 2 sheets of the same material are stacked, heated (to below the recrystallization temperature), and rolled, bonding the 2 sheets together. This sheet is cut in half, the 2 halves are stacked, and the process is repeated several times | https://en.wikipedia.org/wiki?curid=23756855 |
Severe plastic deformation Compared to other SPD processes, ARB has the benefit that it does not require specialized equipment or tooling, only a conventional rolling mill. However, the surfaces to be joined must be well-cleaned before rolling to ensure good bonding. Repetitive corrugation and straightening (RCS) is a severe plastic deformation technique used to process sheet metals. In RCS, a sheet is pressed between two corrugated dies followed by pressing between two flat dies. RCS has gained wide popularity to produce fine grained sheet metals. Endeavors to improve this technique lead to introduce Repetitive Corrugation and Straightening by Rolling (RCSR), a novel SPD method. Applicability of this new method approved in the various materials. In asymmetric rolling (ASR), a rolling mill is modified such that one roll has a higher velocity than the other. This is typically done with either independent speed control or by using rolls of different size. This creates a region in which the frictional forces on the top and bottom of the sheet being rolled are opposite, creating shear stresses throughout the material in addition to the normal compressive stress from rolling. Unlike other SPD processes, ASR does not maintain the same net shape, but the effect on the microstructure of the material is similar. Mechanical alloying/milling (MA/MM) performed in a high-energy ball mill such as a shaker mill or planetary mill will also induce severe plastic deformation in metals | https://en.wikipedia.org/wiki?curid=23756855 |
Severe plastic deformation During milling, particles are fractured and cold welded together, resulting in large deformations. The end product is generally a powder that must then be consolidated in some way (often using other SPD processes), but some alloys have the ability to consolidate "in-situ" during milling. Mechanical alloying also allows powders of different metals to be alloyed together during processing. More recently, the principles behind SPD have been used to develop surface treatments that create a nanocrystalline layer on the surface of a material. In the surface mechanical attrition treatment (SMAT), an ultrasonic horn is connected to an ultrasonic (20 kHz) transducer), with small balls on top of the horn. The workpiece is mounted a small distance above the horn. The high frequency results in a large number of collisions between the balls and the surface, creating a strain rate on the order of 10–10 s. The NC surface layer developed can be on the order of 50 μm thick. The process is similar to shot peening, but the kinetic energy of the balls is much higher in SMAT. An ultrasonic nanocrystalline surface modification (UNSM) technique is also one of the newly developed surface modification technique. In the UNSM process, not only the static load, but also the dynamic load are exerted. The processing is conducted striking a workpiece surface up to 20K or more times per second with shots of an attached ball to the horn in the range of 1K-100K per square millimeter | https://en.wikipedia.org/wiki?curid=23756855 |
Severe plastic deformation The strikes, which can be described as cold-forging, introduce SPD to produce a NC surface layer by refining the coarse grains until nanometer scale without changing the chemical composition of a material which render the high strength and high ductility. This UNSM technique does not only improve the mechanical and tribological properties of a material, but also produces a corrugated structure having numerous of desired dimples on the treated surface. Most research into SPD has focused on grain refinement, which has obvious applications in the development of high-strength materials as a result of the Hall-Petch relation. Conventionally processed industrial metals typically have a grain size from 10–100 μm. Reducing the grain size from 10 μm to 1 μm can increase the yield strength of metals by more than 100%. Techniques that use bulk materials such as ECAE can provide reliable and relatively inexpensive ways of producing ultrafine grain materials compared to rapid solidification techniques such as melt spinning. However, other effects of SPD, such as texture modification also have potential industrial applications as properties such as the Lankford coefficient (important for deep drawing processes) and magnetic properties of electrical steel are highly dependent on texture | https://en.wikipedia.org/wiki?curid=23756855 |
Severe plastic deformation Processes such as ECAE and HPT have also been used to consolidate metal powders and composites without the need for the high temperatures used in conventional consolidation processes such as hot isostatic pressing, allowing desirable characteristics such as nanorystalline grain sizes or amorphous structures to be retained. Some known commercial application of SPD processes are in the production of Sputtering targets by Honeywell and UFG titanium for medical implants. The presence of a high hydrostatic pressure, in combination with large shear strains, is essential for producing high densities of crystal lattice defects, particularly dislocations, which can result in a significant refining of the grains. Grain refinment in SPD processes occurs by a multi-step process: The mechanism by which the subgrains rotate is less understood. Wu "et al." describe a process in which dislocation motion becomes restricted due to the small subgrain size and grain rotation becomes more energetically favorable. Mishra "et al." propose a slightly different explanation, in which the rotation is aided by diffusion along the grain boundaries (which is much faster than through the bulk). F.A. Mohamad has proposed a model for the minimum grain size achievable using mechanical milling. The model is based on the concept that the grain size is dependent on the rates at which dislocations are generated and annihilated | https://en.wikipedia.org/wiki?curid=23756855 |
Severe plastic deformation The full model is given by formula_1 While the model was developed specifically for mechanical milling, it has also been successfully applied to other SPD processes. Frequently only a portion of the model is used (typically the term involving the stacking fault energy) as the other terms are often unknown and difficult to measure. This is still useful as it implies that all other things remaining equal, reducing the stacking fault energy, a property that is a function of the alloying elements, will allow for better grain refinement. A few studies, however, suggested that despite the significance of stacking fault energy on the grain refinement at the early stages of straining, the steady-state grain size at large strains is mainly controlled by the homologous temperature in pure metals and by the interaction of solute atoms and dislocations in single-phase alloys. | https://en.wikipedia.org/wiki?curid=23756855 |
Field metabolic rate (FMR) refers to a measurement of the metabolic rate of a free-living animal. Measurement of the is made using the doubly labeled water method, although alternative techniques, such as monitoring heart rates, can also be used. The advantages and disadvantages of the alternative approaches have been reviewed by Butler, "et al." Several summary reviews have been published. | https://en.wikipedia.org/wiki?curid=23759925 |
Dihydrofuran may refer to: | https://en.wikipedia.org/wiki?curid=23767643 |
C3H6S The molecular formula CHS may refer to: | https://en.wikipedia.org/wiki?curid=23774111 |
C2H4S2 CHS may refer to: | https://en.wikipedia.org/wiki?curid=23774477 |
C6H12S The molecular formula CHS (molar mass: 116.22 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23774491 |
Propiolactone may refer to either of two isomeric chemical compounds: | https://en.wikipedia.org/wiki?curid=23774543 |
Oxetanone may refer to: | https://en.wikipedia.org/wiki?curid=23774645 |
C2O4 CO may refer to: Compounds sharing the molecular formula: | https://en.wikipedia.org/wiki?curid=23774661 |
C6O6 The molecular formula CO (molar mass : 168.06 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=23774697 |
Noro–Frenkel law of corresponding states The is an equation in thermodynamics that describes the critical temperature of the liquid-gas transition T as a function of the range of the attractive potential "R". It states that, all short-ranged spherically symmetric pair-wise additive attractive potentials are characterised by the same thermodynamics properties if compared at the same reduced density and second virial coefficient Johannes Diderik van der Waals's law of corresponding states expresses the fact that there are basic similarities in the thermodynamic properties of all simple gases. Its essential feature is that if we scale the thermodynamic variables that describe an equation of state (temperature, pressure, and volume) with respect to their values at the liquid-gas critical point, all simple fluids obey the same reduced equation of state. Massimo G. Noro and Daan Frenkel formulated an extended law of corresponding states that predicts the phase behaviour of short-ranged potentials on the basis of the effective pair potential alone – extending the validity of the van der Waals law to systems interacting through pair potentials with different functional forms. The Noro–Frenkel law suggests to condensate the three quantities which are expected to play a role in the thermodynamics behavior of a system (hard-core size, interaction energy and range) into a combination of only two quantities: an effective hard core diameter and the reduced second virial coefficient | https://en.wikipedia.org/wiki?curid=23775396 |
Noro–Frenkel law of corresponding states Noro and Frenkel suggested to determine the effective hard core diameter following the expression suggested by Barker based on the separation of the potential into attractive "V" and repulsive "V" parts used in the Weeks–Chandler– Andersen method. The reduced second virial coefficient, i.e., the second virial coefficient "B" divided by the second virial coefficient of hard spheres with the effective diameter can be calculated (or experimentally measured) once the potential is known. "B" is defined as The Noro–Frenkel law is particularly useful for the description of colloidal and globular protein solutions, for which the range of the potential is indeed significantly smaller than the particle size. For these systems the thermodynamic properties can be re-written as a function of only two parameters, the reduced density (using the effective diameter as length scale) and the reduced second-virial coefficient "B". The gas-liquid critical point of all systems satisfying the extended law of corresponding states are characterized by same values of "B" at the critical point. The Noro-Frenkel law can be generalized to particles with limited valency (i.e. to non spherical interactions). Particles interacting with different potential ranges but identical valence behave again according to the generalized law, but with a different value for each valence of "B" at the critical point. | https://en.wikipedia.org/wiki?curid=23775396 |
Peroxide fusion is used to prepare samples for inductively coupled plasma (ICP), atomic absorption (AA) analysis and wet chemistry. Sodium peroxide (NaO) is used to oxidize the sample that becomes soluble in a diluted acid solution. This method allows complete dissolution of numerous refractory compounds like chromite, magnetite, ilmenite, rutile, and even silicon, carbides, alloys, noble metals and materials with high sulfide contents. can be performed either manually or with automated systems. The latter have the advantage of increasing productivity, improving safety, maintaining repeatable preparation conditions, and avoiding spattering as well as cross-contamination. Acid digestion is the most common dissolution method used for many types of samples. Unfortunately, acid digestion involves numerous manipulations of concentrated acids. Some types of samples even require the use of perchloric acid (HClO) that is explosive when it comes into contact with any organic materials. It can be readily combined with hydrofluoric acid (HF) and brought to a fumic state to drive off this volatile acid that is extremely dangerous to human health, not to mention it will dissolve the walls of any glass container it is being processed within. Moreover, it is often difficult to get full dissolution of the sample, even when using these hazardous chemicals. | https://en.wikipedia.org/wiki?curid=23777328 |
Index of pesticide articles This is an index of articles relating to pesticides. | https://en.wikipedia.org/wiki?curid=23781390 |
Pyrethrin I is one of the two pyrethrins, natural organic compounds with potent insecticidal activity. It is an ester of (+)-"trans"-chrysanthemic acid with ("S")-("Z")-pyrethrolone. The synthesis of pyrethrin I involves the esterification of (+)-"trans"-chrysanthemic acid with (S)-(Z)-pyrethrolone. One synthetic method for each of these is shown in the images below. Sobti and Dev of the Malti-Chem Research Centre in Nadesari, vadodara, India published this method for chrysanthemic acid in 1974. The starting material for the synthesis uses commercially available (+)-3α, 4α-epoxycarane (1). A lactone is eventually formed and the ring is opened by the use of a Grignard reagent to give (+)-trans-chrysanthemic acid. The preparation of ("S")-pyrethrolone is essentially a 2 step synthesis. The starting material (S)-4-hydroxy-3-methyl-2-(2-propynyl)-2-cyclopenten-1-one (7) is also commercially available as the alcohol moiety of ETOC. Tetrakis(triphenylphosphine)palladium(0), copper(I) iodide, triethylamine, and vinyl bromide are added to (7) to add two more carbons and form (8). The final step is the addition of an activated zinc compound to reduce the triple carbon bond to form the cis product, ("S")-pyrethrolone (9). Although no journal articles specify the combining of the alcohol and acid moieties of pyrethrin I, they could be combined through an esterification process to form the wanted product. | https://en.wikipedia.org/wiki?curid=23795258 |
Silver-gilt or gilded/gilt silver, sometimes known in American English by the French term vermeil, is silver (either pure or sterling) which has been gilded with gold. Most large objects made in goldsmithing that appear to be gold are actually silver-gilt; for example most sporting trophies (including medals such as the gold medals awarded in all Olympic Games after 1912) and many crown jewels are silver-gilt objects. Apart from the raw materials being much less expensive to acquire than solid gold of any karat, large silver-gilt objects are also noticeably lighter if lifted, as well as more durable (gold is much heavier than even lead and is easily scratched and bent). For objects that have intricate detail like monstrances, gilding greatly reduces the need for cleaning and polishing, and so reduces the risk of damage. Ungilded silver would suffer oxidation and need frequent polishing; gold does not oxidize at all. The "gold" threads used in embroidered goldwork are normally also silver-gilt. objects have been made since ancient times across Eurasia, using a variety of gilding techniques, and a distinctive depletion gilding technique was developed by the Incas in Pre-Columbian South America | https://en.wikipedia.org/wiki?curid=23800578 |
Silver-gilt "Overlaying" or folding or hammering on gold foil or gold leaf is mentioned in Homer's Odyssey (Bk vi, 232), and fire-gilding with mercury dates to at least the 4th century BC, and was the most common method until the Early Modern period at least, though dangerous for the workers and often caused blindness among French artisans who refined the technique in the 18th century. Today electroplating is the most commonly used method: it involves no mercury and is therefore much safer. Keum-boo is a special Korean technique of silver-gilding, using depletion gilding. In China gilt-bronze, also known as ormolu, was more common. Vermeil ( or ; ) is an alternative for the usual term silver-gilt. It is a French word which came into use in the English language, mostly in America, in the 19th century, and is rare in British English. "Vermeil" can also refer to gilt bronze, an even less costly alternative construction material than silver. The US Code of Federal Regulations 16, Part 23.5 defines "vermeil" thus: "An industry product may be described or marked as 'vermeil' if it consists of a base of sterling silver coated or plated on all significant surfaces with gold or gold alloy of not less than 10-karat fineness, that is of substantial thickness and a minimum thickness throughout equivalent to two and one half () microns (or approximately of an inch) of fine gold | https://en.wikipedia.org/wiki?curid=23800578 |
Silver-gilt " Silver objects could be gilded at any point, not just when first made, and items regularly handled, such as toilet service sets for dressing-tables or tableware, often needed regilding after a few years, as the gold began to wear off. In 18th century London two different silversmiths charged 3 shillings per ounce of silver for an initial gilding, and 1 shilling and 9 pence per ounce for regilding. Often only the interior of cups was gilded, perhaps from concern at the chemical compounds used to clean tarnish from silver. This is called parcel-gilt. Fully silver-gilt items are visually indistinguishable from gold, and were no doubt often thought to be solid gold. When the English Commonwealth sold the Crown Jewels of England after the execution of Charles I they were disappointed in the medieval "Queen Edith's Crowne, formerly thought to be of massy gold, but upon trial found to be of silver gilt", which was valued at only £16, compared to £1,110 for the "imperial crowne". The English Gothic Revival architect Sir George Gilbert Scott was concerned by the morality of this. Gilding of the interior only he accepted, but with all-over gilding "we ... reach the actual boundary of truth and falsehood; and I am convinced that if we adopt this custom we overstep it... why make our gift look more costly than it is? We increase its beauty, but it is at the sacrifice of truth." Indeed, some Early Medieval silver-gilt Celtic brooches had compartments apparently for small lead weights to aid such deception. | https://en.wikipedia.org/wiki?curid=23800578 |
Corby toxic waste case The was a court case decided by The Hon. Mr. Justice Akenhead at the High Court of Justice, London, on 29 July 2009 in the case of Corby Group Litigation v. Corby Borough Council [2009] EWHC 1944 (TCC). The judge found Corby Borough Council liable in negligence, public nuisance and a breach of statutory duty for its reclamation of a Corby Steelworks in the town of Corby, Northamptonshire, between 1985 and 1997. The landmark decision was historically significant as the first in the world to establish a link between atmospheric toxic waste and birth defects - all previous cases have involved water pollution - and held implications for other council reclamation programs and the methods of conducting reclamation in England and Wales. The case has been described as "the British Erin Brockovich". Corby became a steelmaking centre through the establishment of the Stewarts & Lloyds production site in the 1930s, and by 1960 had grown to become one of the most heavily industrialised areas in the Midlands. In 1981 however the plant had become unprofitable and owners British Steel Corporation closed the site. By then it was one of the largest steelmaking operations in Western Europe, covering , with four blast furnaces, two coke oven complexes and associated facilities. During its operation a huge quantity of industrial waste, including toxic waste, had been deposited there | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case Between 1984 and 1999 Corby Borough Council undertook the demolition, excavation and redevelopment of the site as part of a program of urban regeneration. This involved transporting the waste through populated areas to a quarry north of the site, utilising up to 200 vehicle movements daily. The toxic waste was carried in open lorries, spilling sludge over the roads and releasing huge amounts of dust into the air. Subsequently, in the late 1980s and 1990s, the rates of upper-limb defects in babies born in Corby were found to be almost three times higher than those of children born in the surrounding area and ten times higher than a town with a population of 60,000 should expect. In all cases initially referred to the court there were no previous family histories of limb defect. In November 2005 expert evidence was submitted to the High Court in London by the mothers of thirty children who claimed that during their pregnancies they were exposed to contamination from the waste removal operations and who sought to bring a legal action to try to prove a link between the mismanagement of the toxic waste and the birth defects suffered by their children. The evidence presented included reports detailing the higher rate of birth defects, and alleging that exposure to the toxic waste was the likely cause of the children's deformities | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case They also presented a report written by Roger Braithwaite, an environmental expert instructed by the families, which concluded that the negligent handling of the waste by Corby Borough Council demonstrated "naivety, arrogance, ignorance, incompetence and a possible serious conflict of interest... At this early stage it would seem to me that these... badly polluted lands have never been effectively or comprehensively assessed, properly permitted, regulated, monitored or adequate records maintained... This is environmental negligence on a grand scale." After reviewing the evidence presented by all parties to the case, an order approved by the then Lord Chief Justice, Lord Phillips of Worth Matravers, set out the terms of the litigation in relation to the council's management and execution of the "land reclamation contracts" between 1985 and 1999 and any duty they had to the families, and permission was given for the parents to pursue the claim against Corby Borough Council as a class action involving children born between 1985 and 1999. The case to be heard at the High Court in 2009 represented 18 young people who alleged that toxic waste dumped by Corby Borough Council between 1984 and 1999 was the cause of their deformities. All had serious disabilities, including missing or underdeveloped fingers and deformities of their feet. They alleged that their mothers ingested or inhaled the toxic substances that affected the development of their limbs while they were still in the womb | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case All of their mothers either lived in or regularly visited Corby between 1984 and 1999 when the work was carried out across the town. The case had taken ten years to reach this point largely because of the difficulties encountered in obtaining disclosure of information from Corby Borough Council. When the case reached the High Court on 16 February 2009, involving 18 families and the culmination of a ten-year legal process, evidence was put forward describing how, between 1985 and 1997, there existed a possibility that expectant mothers could have been affected by toxic waste which could either have travelled by air as a consequence of dust, or could have been ingested after landing on vegetables or other items. The area was constantly coated with a thick, red dust, including an open air market selling vegetables and other produce. The vehicles were uncovered, and there was no adherence to procedures such as the wheel washing of the vehicles. David Wilby, QC, leading counsel for the claimants, stated in court that one expert, in trying to convey the appearance of the minute particles hanging over the town at that time, had described it as an "atmospheric soup of toxic materials". Some of the open-backed lorries transported so-called 'wet waste', containing dioxins and heavy metals such as cadmium, lead and chromium. With regard to the allegations that the council demonstrated a conflict of interest, Wilby stated: "Their motive - to a very considerable degree - was money | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case They looked to the Government and to the redevelopment organisations for the funds to redevelop the sites. They used that money to pay local contractors and the reality was that many of the contracts were awarded to friends or former work colleagues of members of the council." In 1997 police investigated allegations of corruption in the awarding of the contracts but the Crown Prosecution Service decided there was insufficient evidence to proceed. The presence and locations of the toxic waste was known before work began, having been stored in purpose-built "pits" around the site by British Steel, "in a form which was of no danger to anyone unless they fell in. But the effect of the works undertaken was to remove the majority of these materials and move them a long distance to other areas of Corby, and this involved vast numbers of vehicle movements." Professor Louise Parker PhD, Professor of Pediatrics and Community Health and Epidemiology at Dalhousie University, Halifax, Nova Scotia, Canada, testified that between 1989 and 1998 children in Corby were 2.5 times more likely to be born with upper limb defects than in the rest of the Kettering Health Authority area, which was statististically "quite significant" | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case An internal report prepared by Corby Borough Council was uncovered which had raised the prospect of residents being exposed to high levels of zinc, arsenic, boron and nickel as a result of the reclamation works, and a separate report, from the council’s auditor, complained of incompetence and negligence by the council and said there was a "cavalier approach" to the operation. The families' counsel submitted that whether Corby Borough Council knew or should have known that the substances being transported around the town could have been hazardous to health was "hardly rocket science". Further, Wilby submitted that the Council committed a criminal act when they allowed the movement of toxic waste without a licence: in 1986 there was no proper permission in place for moving the contaminated waste, only for moving 'inert' waste. Inspectors were not told the true nature of the substances involved and so took only sporadic samples from the site. Wilby said that the council had deliberately ignored the advice from experts to properly analyse the site because it was going to be an expensive task. He said: "They decided they were going to do this 'dig-and-dump'. They thought 'we have got this great deal of land and all this spoil on this site which must be contaminated, we have got to get it off there because we'll never be able to sell it.'" Records demonstrated that in one test which took place in 1983 only five soil samples were collected to represent a area | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case In his ruling, Mr Justice Akenhead said it was clear that the council had permitted toxic waste to disperse into the atmosphere. He also said that there was a "statistically significant" cluster of birth defects between 1989 and 1999, and that, "toxicologically, there were present on and from the Corby Borough Council sites, over the whole period from 1985 (and possibly before) until 1997, the types of contaminants which could cause the birth defects complained of." "There was an extended period between 1983 and August 1997 in which Corby Borough Council was extensively negligent in its control and management of the sites which they acquired from British Steel and otherwise used. That negligence and, as from April 1, 1992, breach of statutory duty on the part of CBC permitted and led to the extensive dispersal of contaminated mud and dust over public areas of Corby and into and over private homes, with the result that the contaminants could realistically have caused the types of birth defects of which complaint has been made by the claimants (save in limited respects)... Corby Borough Council is liable in public nuisance, negligence and breach of statutory duty, obviously subject to it being established in later proceedings by individual claimants that their particular conditions were actually caused by the defaults identified in this judgment | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case " Mr Justice Akenhead said that while the parents had been "wholly honest", the council's motive was to develop and sell the land quickly without thought for the consequences of those nearby, and without appreciating "the enormity, ramifications and difficulty" of its task in moving the material. The two youngest claimants, nine-year-old India Harrison and ten-year-old Ashleigh Jane Custance, were unable at that time to proceed with their cases, however, because of the ruling that there were no breaches of duty after August 1997. Their parents indicated that they would appeal this cut-off date. The families' lawyer, Des Collins, said: "Prior to the trial, the council maintained that a thorough investigation had led it to the conclusion that there was no link between the reclamation work and the children's birth defects. It also maintained that had any convincing evidence been shown that the children had good claims then the council would have wanted to compensate them appropriately without going to trial. Today that link has been established and the evidence provided. The children now call upon the council to fulfil their pre-trial promises without delay." Collins said of the legal battle: "I've been made out to be a shyster and an ambulance-chaser. The council has stonewalled, obstructed and prevaricated all the way through this. They didn't need to. If they'd ever said to us, 'Look, we're not admitting liability, but we'll co-operate with you to find out what really happened', I wouldn't have minded | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case Instead, they tried to shut us out and paint us as the baddies... They've tried at every turn to stop us getting at the truth. Now they claim they can't afford to pay. I'm not impressed." Corby Borough Council's Chief Executive Chris Mallender said: "We are obviously very disappointed and very surprised at the outcome of this trial. Our position has always been that there was no link between the reclamation work that was carried out in Corby in past decades and these children's birth defects. That is still our position." He also said they were "prepared to apologise for mistakes that had been made but could not apologise until a causal link was proved between the works and the defects... We are not yet at the point of saying sorry because nobody yet is responsible." The council's legal representatives said they were asked to advise on an appeal but had over 400 pages of judgment to review and also their client had to consider its position. The firm said it would be a few weeks before it has instructions. The statement added: "There are however some clear points to note at this stage. The case involves reclamation work going back to the 1980s. The judge concluded that this contamination affected pregnant women. A child, so affected, has 21 years from birth to make a claim and thus any work since the late 1980s which has not met the standard of care indicated in this judgment could be challenged in this way | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case For both local authorities and developers alike this is a significant concern because the standard of care has been drawn very highly, and could cause a rethink of the way that reclamation is carried out in the UK even though the facts of the case are historic." Kelvin Glendenning, leader of Corby Borough Council between 1984 and 1995, said "I don't think that Corby Council has anything to regret... If there was toxic waste - and I am sure there wasn't any toxic waste at all that was floating about in the air - they shouldn't be blaming us." On 1 August 2009 it was announced that the decision by Corby Borough Council regarding whether or not to appeal the ruling would be taken on 18 August 2009, the day before the deadline for appeal decisions to be submitted to Mr Justice Akenhead. Unusually, the authority decided that openness and public opinion were required at the extraordinary full council sitting after which councillors will vote on whether to appeal or instead pay the compensation to 16 children who were born with birth defects. Chief Executive Chris Mallender stated: "The council is doing the right thing by reaching the decision in public. We will be starting the meeting at 6pm so we can give the opportunity for [the public] to speak," a move he said would make sure councillors' decisions reflected public opinion. The council, which has an annual budget of £12m, has already spent £1.9m fighting the case and has now received a bill for £4.7m from the families' solicitor | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case Compensation payments could total in excess of a further £8m. At the meeting the council voted to appeal against the ruling but said that they would follow a "twin track" approach, preferring to attend independent mediation sessions to come to an out-of-court settlement with the families. They also stated that any mediation would include the cases of the two youngest claimants despite these not being covered by the ruling. The chief executive gave a statement that if a causal link between the toxins and the limb deformities was ever proven he would "offer an unreserved apology", however he believed "that the judgement is unsound and will be found wanting on appeal." The settlement was mediated by retired judge Sir Henry Brooke. Before settlement had been reached, Chris Mallender explained: "We have reached a view that there are going to be no outright winners in this. In the circumstances we feel that it's better that we try and find a middle ground, we settle in a way that's fair to the families, but is also fair in terms of the residual burden on the council tax payer." On 16 April 2010 the council released a joint statement with the families' solicitors announcing it was dropping its appeal and had agreed a financial settlement with 19 families. Chris Mallender said: "The council recognises that it made mistakes in its clean-up of the former British Steel site years ago and extends its deepest sympathy to the children and their families | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case Although I accept that money cannot properly compensate these young people for their disabilities and for all that they have suffered to date and their problems in the future, the council sincerely hopes that this apology coupled with today's agreement will mean that they can now put their legal battle behind them and proceed with their lives with a greater degree of financial certainty." The financial terms of the settlement remained confidential, and the agreement forbids disclosure of the financial arrangements. On the subject of cost, Mallender said: "Every £1m of cost involves a payment £5 per household in Corby on average, per year, for the next 20 years. So, simple maths: if the overall bill is £5m, it's £25 per household for 20 years." The settlement also encompassed three children not covered by the original ruling, including India Harrison and Ashleigh Custance. Paula Jefferson, head of Beachcroft LLP's Disease Group, said: "Any organisation involved in any activity in the future, where there is the potential for release of harmful substances in to the atmosphere, should ensure that they have taken all necessary steps to identify the potential contamination and to then ensure that they either employ, or have themselves the necessary skills, to deal with that contamination. The principles in the judgment apply not just when there is demolition in progress, but to any activity where there is potential for exposure in to the atmosphere | https://en.wikipedia.org/wiki?curid=23802230 |
Corby toxic waste case Where there is any known potential for such exposure, then regard should be had to not just the onsite workforce but also to those living and working in the surrounding area. In the Corby case the area of risk was 4km from the demolition site. The area for potential exposure will clearly vary depending on the circumstances of each case. In essence, the message remains the same - proper risk assessment is key and must include identifying the appropriate people to do the job and not cutting corners, which, as has been proved for Corby Borough Council, is likely to be false economy." | https://en.wikipedia.org/wiki?curid=23802230 |
Agilent ChemStation is a software package to control Agilent liquid chromatography, gas chromatography, and ultraviolet-visible spectroscopy systems such as the 1050, 1100 and 1200 Series HPLC system and the 8453 and 8454 single-beam diode array detector spectrophotometers. It is an evolution of the Hewlett-Packard ChemStation System. Two versions are available: one ("online") in connection with the modules of the HPLC chain is designed to control instruments and run experiments, and the other ("offline"), without a connection with the HPLC chain, is designed to analyze data. ChemStation is structured around a number of registers. Two of the more important registers are CHROMREG and CHROMRES, the chromatographic data registers. Other special registers exist for the UV-vis implementation of the software. ChemStation has a command line interpreter and can run macros. Those macros are files grouping a set of commands. These files possess a .mac extension. ChemStation can import analysis lists and export result files in XML by adding new lines to the ChemStation.ini configuration file. This is a feature to implement the connection with a Laboratory information management system (LIMS). | https://en.wikipedia.org/wiki?curid=23803311 |
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