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CKIδ activity is implicated in mitosis and in response to DNA damage. During interphase, CKIδ associates with the Golgi Apparatus and appears to regulate the budding of clathrin coated vesicles from the TGN; it also appears to associate with tubulin. While undamaged mitotic cells shows no CKIδ association with tubulin, the kinase was recruited during mitosis in cells with DNA damage, indicative of a role for CKIδ in arranging the microtubule network during mitosis. The mechanisms for these biochemical interactions remain unknown. | 1 | Applied and Interdisciplinary Chemistry |
The standards are listed in . Primary standards are designed to protect human health, with an adequate margin of safety, including sensitive populations such as children, the elderly, and individuals suffering from respiratory diseases. Secondary standards are designed to protect public welfare, damage to property, transportation hazards, economic values, and personal comfort and well-being from any known or anticipated adverse effects of a pollutant. A district meeting a given standard is known as an "attainment area" for that standard, and otherwise a "non-attainment area".
Standards are required to "accurately reflect the latest scientific knowledge," and are reviewed every five years by a Clean Air Scientific Advisory Committee (CASAC), consisting of "seven members appointed by the EPA administrator."
EPA has set NAAQS for six major pollutants listed as below. These six are also the criteria air pollutants.
* Each standard has its own criteria for how many times it may be exceeded
* As of June 15, 2005, the 1-hour ozone standard no longer applies to areas designated with respect to the 8-hour ozone standard (which includes most of the United States, except for portions of 10 states).
* Source: [https://www.epa.gov/criteria-air-pollutants/naaqs-table USEPA] | 1 | Applied and Interdisciplinary Chemistry |
* Shakiness
* Dry cough
* Dizziness and light-headedness due to low blood pressure
* Fatigue, especially in the early stages
* Mouth dryness in the early stages
* Nausea
* Fainting
* Signs of infection (e.g., fever, chills, persistent sore throat)
* Chest pain
* Neutropenia (low white blood cells)
* Impotence (erectile dysfunction)
* Hyperkalemia
Serious allergic reactions to this drug are unlikely, but immediate medical attention must be sought if they occur. Symptoms of a serious allergic reaction include, but are not limited to a rash or swelling of the face, mouth, tongue, or throat. In extreme cases, ramipril may lead to potentially fatal liver problems. | 0 | Theoretical and Fundamental Chemistry |
This pathway is a part of the glutamate family of amino acid biosynthetic pathways. The reaction steps in the pathway are similar to the citric acid cycle.
The first step in the pathway is condensation of acetyl-CoA with α-ketoglutarate, which gives homocitrate. This reaction is catalyzed by homocitrate synthase. Homocitrate is then converted to homoaconitate by homoaconitase and then to homoisocitrate. This is then decarboxylated by homoisocitrate dehydrogenase, which results in α-ketoadipate. A nitrogen atom is added from glutamate by aminoadipate aminotransferase to form the α-aminoadipate, from which this pathway gets its name. This is then reduced by aminoadipate reductase via an acyl-enzyme intermediate to a semialdehyde. Reaction with glutamate by one class of saccharopine dehydrogenase yields saccharopine which is then cleaved by a second saccharopine dehydrogenase to yield lysine and oxoglutarate.
Conversion of lysine to α-ketoadipate during degradation of lysine proceeds via the same steps, but in reverse. | 1 | Applied and Interdisciplinary Chemistry |
Pewter, being a softer material, can be manipulated in various ways such as being cast, hammered, turned, spun and engraved.
Given that pewter is soft at room temperature, a pewter bell does not ring clearly. Cooling it in liquid nitrogen hardens it and enables it to ring, but also makes it more brittle. | 1 | Applied and Interdisciplinary Chemistry |
An optode requires three components to function: a chemical that responds to an analyte, a polymer to immobilise the chemical transducer and instrumentation (optical fibre, light source, detector and other electronics). Optodes usually have the polymer matrix coated onto the tip of an optical fibre, but in the case of evanescent wave optodes the polymer is coated on a section of fibre that has been unsheathed. | 0 | Theoretical and Fundamental Chemistry |
The Kuhn length is a theoretical treatment, developed by Werner Kuhn, in which a real polymer chain is considered as a collection of Kuhn segments each with a Kuhn length . Each Kuhn segment can be thought of as if they are freely jointed with each other. Each segment in a freely jointed chain can randomly orient in any direction without the influence of any forces, independent of the directions taken by other segments. Instead of considering a real chain consisting of bonds and with fixed bond angles, torsion angles, and bond lengths, Kuhn considered an equivalent ideal chain with connected segments, now called Kuhn segments, that can orient in any random direction.
The length of a fully stretched chain is for the Kuhn segment chain. In the simplest treatment, such a chain follows the random walk model, where each step taken in a random direction is independent of the directions taken in the previous steps, forming a random coil. The average end-to-end distance for a chain satisfying the random walk model is .
Since the space occupied by a segment in the polymer chain cannot be taken by another segment, a self-avoiding random walk model can also be used. The Kuhn segment construction is useful in that it allows complicated polymers to be treated with simplified models as either a random walk or a self-avoiding walk, which can simplify the treatment considerably.
For an actual homopolymer chain (consists of the same repeat units) with bond length and bond angle θ with a dihedral angle energy potential, the average end-to-end distance can be obtained as
::where is the average cosine of the dihedral angle.
The fully stretched length . By equating the two expressions for and the two expressions for from the actual chain and the equivalent chain with Kuhn segments, the number of Kuhn segments and the Kuhn segment length can be obtained.
For worm-like chain, Kuhn length equals two times the persistence length. | 0 | Theoretical and Fundamental Chemistry |
A conventional pollutant is a term used in the USA to describe a water pollutant that is amenable to treatment by a municipal sewage treatment plant. A basic list of conventional pollutants is defined in the U.S. Clean Water Act. The list has been amended in regulations issued by the Environmental Protection Agency:
* biochemical oxygen demand (BOD)
* fecal coliform bacteria
* oil and grease
* pH (exceeding regulatory limits)
* total suspended solids (TSS).
The Secondary Treatment Regulation contains national discharge standards for BOD, pH and TSS, applicable to sewage treatment plants in the U.S. | 1 | Applied and Interdisciplinary Chemistry |
Bromocresol green (BCG) is a dye of the triphenylmethane family (triarylmethane dyes). It belongs to a class of dyes called sulfonephthaleins. It is used as a pH indicator in applications such as growth mediums for microorganisms and titrations. In clinical practise, it is commonly used as a diagnostic technique. The most common use of bromocresol green is to measure serum albumin concentration within mammalian blood samples in possible cases of kidney failure and liver disease. In chemistry, bromocresol green is used in Thin-layer chromatography staining solutions to visualize acidic compounds. | 0 | Theoretical and Fundamental Chemistry |
Omics based methods use omics technologies, such as chemoproteomics, reverse genetics and genomics, transcriptomics, and proteomics, to identify the potential targets of the compound of interest. Reverse genetics and genomics approaches, for instance, uses genetic perturbation (e.g. CRISPR-Cas9 or siRNA) in combination with the compound to identify genes whose knockdown or knockout abolishes the pharmacological effect of the compound. On the other hand, transcriptomics and proteomics profiles of the compound can be used to compare with profiles of compounds with known targets. Thanks to computation inference, it is then possible to make hypotheses about the mechanism of action of the compound, which can subsequently be tested. | 1 | Applied and Interdisciplinary Chemistry |
Usually the endosymbiosis event is considered to have occurred in the Archaeplastida, within which the glaucophyta being the possible earliest diverging lineage. The glaucophyte chloroplast group is the smallest of the three primary chloroplast lineages, being found in only 13 species, and is thought to be the one that branched off the earliest. Glaucophytes have chloroplasts that retain a peptidoglycan wall between their double membranes, like their cyanobacterial parent. For this reason, glaucophyte chloroplasts are also known as muroplasts (besides cyanoplasts or cyanelles). Glaucophyte chloroplasts also contain concentric unstacked thylakoids, which surround a carboxysome – an icosahedral structure that glaucophyte chloroplasts and cyanobacteria keep their carbon fixation enzyme RuBisCO in. The starch that they synthesize collects outside the chloroplast. Like cyanobacteria, glaucophyte and rhodophyte chloroplast thylakoids are studded with light collecting structures called phycobilisomes. For these reasons, glaucophyte chloroplasts are considered a primitive intermediate between cyanobacteria and the more evolved chloroplasts in red algae and plants. | 0 | Theoretical and Fundamental Chemistry |
Ethylene oxide is widely used to generate detergents and surfactants by ethoxylation. Its hydrolysis affords ethylene glycol. It is also used for sterilisation of medical instruments and materials.
The reaction of epoxides with amines is the basis for the formation of epoxy glues and structural materials. A typical amine-hardener is triethylenetetramine (TETA). | 0 | Theoretical and Fundamental Chemistry |
The Phosphagen System (ATP-PCr) occurs in the cytosol (a gel-like substance) of the sarcoplasm of skeletal muscle, and in the myocyte's cytosolic compartment of the cytoplasm of cardiac and smooth muscle.
During muscle contraction:
:HO + ATP → H + ADP + P (Mg assisted, utilization of ATP for Muscle contraction by ATPase)
:H + ADP + CP → ATP + Creatine (Mg assisted, catalyzed by creatine kinase, ATP is used again in the above reaction for continued muscle contraction)
:2 ADP → ATP + AMP (catalyzed by adenylate kinase/myokinase when CP is depleted, ATP is again used for muscle contraction)
Muscle at rest:
:ATP + Creatine → ADP + CP + H (Mg assisted, catalyzed by creatine kinase)
:ADP + P → ATP (during anaerobic glycolysis and oxidative phosphorylation)
When the Phosphagen System has been depleted of phosphocreatine (creatine phosphate), the resulting AMP produced from the adenylate kinase (myokinase) reaction is primarily regulated by the Purine Nucleotide Cycle. | 1 | Applied and Interdisciplinary Chemistry |
Deviation from the experiment is not recommended, and has been linked with accidents. Candy with low moisture content or high surface area may cause explosions. | 1 | Applied and Interdisciplinary Chemistry |
Careful and well informed writers about thermodynamics, in their accounts of thermodynamic equilibrium, often enough make provisos or reservations to their statements. Some writers leave such reservations merely implied or more or less unstated.
For example, one widely cited writer, H. B. Callen writes in this context: "In actuality, few systems are in absolute and true equilibrium." He refers to radioactive processes and remarks that they may take "cosmic times to complete, [and] generally can be ignored". He adds "In practice, the criterion for equilibrium is circular. Operationally, a system is in an equilibrium state if its properties are consistently described by thermodynamic theory!"
J.A. Beattie and I. Oppenheim write: "Insistence on a strict interpretation of the definition of equilibrium would rule out the application of thermodynamics to practically all states of real systems."
Another author, cited by Callen as giving a "scholarly and rigorous treatment", and cited by Adkins as having written a "classic text", A.B. Pippard writes in that text: "Given long enough a supercooled vapour will eventually condense, ... . The time involved may be so enormous, however, perhaps 10 years or more, ... . For most purposes, provided the rapid change is not artificially stimulated, the systems may be regarded as being in equilibrium."
Another author, A. Münster, writes in this context. He observes that thermonuclear processes often occur so slowly that they can be ignored in thermodynamics. He comments: "The concept absolute equilibrium or equilibrium with respect to all imaginable processes, has therefore, no physical significance." He therefore states that: "... we can consider an equilibrium only with respect to specified processes and defined experimental conditions."
According to L. Tisza: "... in the discussion of phenomena near absolute zero. The absolute predictions of the classical theory become particularly vague because the occurrence of frozen-in nonequilibrium states is very common." | 0 | Theoretical and Fundamental Chemistry |
The most common application for an air-mixing plenum is the mixing of return air (or extract air) with fresh air to provide a supply air mixture for onward distribution to the building or area which the ventilation system is serving. The air transferred from the return air stream to the supply air stream is termed recirculated air. All air not mixed is rejected to the atmosphere as exhaust air. Air streams are mixed to save energy and improve energy efficiency. | 1 | Applied and Interdisciplinary Chemistry |
Scientists use OVERFLOW to better understand the aerodynamic forces on a vehicle by evaluating the flowfield surrounding the vehicle. While wind tunnel testing provides limited data at many flow conditions, CFD simulations provide detailed information about selected conditions, and also provide a distribution of forces on the vehicle, aiding in structural design.
OVERFLOW has also been used to simulate the effect of debris on the space shuttle launch vehicle. | 1 | Applied and Interdisciplinary Chemistry |
The HIV-1 integrase (IN) is a key enzyme in the replication mechanism of retroviruses. It is responsible for the transfer of virally encoded DNA into the host chromosome which is a necessary event in retroviral replication. Since IN has no equivalent in the host cell, integrase inhibitors have a high therapeutic index as they do not interfere with normal cellular processes. | 1 | Applied and Interdisciplinary Chemistry |
A ribosome binding site, or ribosomal binding site (RBS), is a sequence of nucleotides upstream of the start codon of an mRNA transcript that is responsible for the recruitment of a ribosome during the initiation of translation. Mostly, RBS refers to bacterial sequences, although internal ribosome entry sites (IRES) have been described in mRNAs of eukaryotic cells or viruses that infect eukaryotes. Ribosome recruitment in eukaryotes is generally mediated by the 5' cap present on eukaryotic mRNAs. | 1 | Applied and Interdisciplinary Chemistry |
Isolated restriction enzymes are used to manipulate DNA for different scientific applications.
They are used to assist insertion of genes into plasmid vectors during gene cloning and protein production experiments. For optimal use, plasmids that are commonly used for gene cloning are modified to include a short polylinker sequence (called the multiple cloning site, or MCS) rich in restriction enzyme recognition sequences. This allows flexibility when inserting gene fragments into the plasmid vector; restriction sites contained naturally within genes influence the choice of endonuclease for digesting the DNA, since it is necessary to avoid restriction of wanted DNA while intentionally cutting the ends of the DNA. To clone a gene fragment into a vector, both plasmid DNA and gene insert are typically cut with the same restriction enzymes, and then glued together with the assistance of an enzyme known as a DNA ligase.
Restriction enzymes can also be used to distinguish gene alleles by specifically recognizing single base changes in DNA known as single-nucleotide polymorphisms (SNPs). This is however only possible if a SNP alters the restriction site present in the allele. In this method, the restriction enzyme can be used to genotype a DNA sample without the need for expensive gene sequencing. The sample is first digested with the restriction enzyme to generate DNA fragments, and then the different sized fragments separated by gel electrophoresis. In general, alleles with correct restriction sites will generate two visible bands of DNA on the gel, and those with altered restriction sites will not be cut and will generate only a single band. A DNA map by restriction digest can also be generated that can give the relative positions of the genes. The different lengths of DNA generated by restriction digest also produce a specific pattern of bands after gel electrophoresis, and can be used for DNA fingerprinting.
In a similar manner, restriction enzymes are used to digest genomic DNA for gene analysis by Southern blot. This technique allows researchers to identify how many copies (or paralogues) of a gene are present in the genome of one individual, or how many gene mutations (polymorphisms) have occurred within a population. The latter example is called restriction fragment length polymorphism (RFLP).
Artificial restriction enzymes created by linking the FokI DNA cleavage domain with an array of DNA binding proteins or zinc finger arrays, denoted zinc finger nucleases (ZFN), are a powerful tool for host genome editing due to their enhanced sequence specificity. ZFN work in pairs, their dimerization being mediated in-situ through the FokI domain. Each zinc finger array (ZFA) is capable of recognizing 9–12 base pairs, making for 18–24 for the pair. A 5–7 bp spacer between the cleavage sites further enhances the specificity of ZFN, making them a safe and more precise tool that can be applied in humans. A recent Phase I clinical trial of ZFN for the targeted abolition of the CCR5 co-receptor for HIV-1 has been undertaken.
Others have proposed using the bacteria R-M system as a model for devising human anti-viral gene or genomic vaccines and therapies since the RM system serves an innate defense-role in bacteria by restricting tropism by bacteriophages. There is research on REases and ZFN that can cleave the DNA of various human viruses, including HSV-2, high-risk HPVs and HIV-1, with the ultimate goal of inducing target mutagenesis and aberrations of human-infecting viruses. The human genome already contains remnants of retroviral genomes that have been inactivated and harnessed for self-gain. Indeed, the mechanisms for silencing active L1 genomic retroelements by the three prime repair exonuclease 1 (TREX1) and excision repair cross complementing 1(ERCC) appear to mimic the action of RM-systems in bacteria, and the non-homologous end-joining (NHEJ) that follows the use of ZFN without a repair template. | 1 | Applied and Interdisciplinary Chemistry |
The use of micelles in high performance liquid chromatography was first introduced by Armstrong and Henry in 1980. The technique is used mainly to enhance retention and selectivity of various solutes that would otherwise be inseparable or poorly resolved. Micellar liquid chromatography (MLC) has been used in a variety of applications including separation of mixtures of charged and neutral solutes, direct injection of serum and other physiological fluids, analysis of pharmaceutical compounds, separation of enantiomers, analysis of inorganic organometallics, and a host of others.
One of the main drawbacks of the technique is the reduced efficiency that is caused by the micelles. Despite the sometimes poor efficiency, MLC is a better choice than ion-exchange LC or ion-pairing LC for separation of charged molecules and mixtures of charged and neutral species. Some of the aspects which will be discussed are the theoretical aspects of MLC, the use of models in predicting retentive characteristics of MLC, the effect of micelles on efficiency and selectivity, and general applications of MLC.
Reverse phase high-performance liquid chromatography (RP-HPLC) involves a non-polar stationary phase, often a hydrocarbon chain, and a polar mobile or liquid phase. The mobile phase generally consists of an aqueous portion with an organic addition, such as methanol or acetonitrile. When a solution of analytes is injected into the system, the components begin to partition out of the mobile phase and interact with the stationary phase. Each component interacts with the stationary phase in a different manner depending upon its polarity and hydrophobicity. In reverse phase HPLC, the solute with the greatest polarity will interact less with the stationary phase and spend more time in the mobile phase. As the polarity of the components decreases, the time spent in the column increases. Thus, a separation of components is achieved based on polarity. The addition of micelles to the mobile phase introduces a third phase into which the solutes may partition. | 0 | Theoretical and Fundamental Chemistry |
The theoretical SV of a pure triglyceride molecule can be calculated by the following equation (where MW is its molecular weight):
:where:
:3 is the number of fatty acids residues per triglyceride
:1000 is the conversion factor for milligrams to grams
:56.1 is the molar mass of KOH.
For instance, triolein, a triglyceride occurring in many fats and oils, has three oleic acid residues esterified to a molecule of glycerol with a total MW of 885.4 (g / mol). Therefore, its SV equals 190 mg KOH / g sample. In comparison, trilaurin with three shorter fatty acid residues (lauric acid) has a MW of 639 and an SV of 263.
As it can be seen from equation (2), the SV of a given fat is inversely proportional to its molecular weight. Actually, as fats and oils contain a mix of different triglycerides species, the average MW can be calculated according to the following relation:
This means that coconut oil with an abundance of medium chain fatty acids (mainly lauric acid) contain more fatty acids per unit of weight than, for example, olive oil (mainly oleic acid). Consequently, more ester saponifiable functions were present per g of coconut oil, which means more KOH is required to saponify the same amount of matter, and thus a higher SV. The calculated molecular weight (Eq. 3) is not applicable to fats and oils containing high amounts of unsaponifiable material, free fatty acids (> 0.1%), or mono- and diacylglycerols (> 0.1%). | 0 | Theoretical and Fundamental Chemistry |
Magnetometers based on helium-4 excited to its metastable triplet state thanks to a plasma discharge have been developed in the 1960s and 70s by Texas Instruments, then by its spinoff Polatomic, and from late 1980s by CEA-Leti. The latter pioneered a configuration which cancels the dead-zones, which are a recurrent problem of atomic magnetometers. This configuration was demonstrated to show an accuracy of 50 pT in orbit operation. The ESA chose this technology for the Swarm mission, which was launched in 2013. An experimental vector mode, which could compete with fluxgate magnetometers was tested in this mission with overall success. | 0 | Theoretical and Fundamental Chemistry |
Double-acting cylinders (DAC) use the force of air to move in both extend and retract strokes. They have two ports to allow air in, one for outstroke and one for instroke. Stroke length for this design is not limited, however, the piston rod is more vulnerable to buckling and bending. Additional calculations should be performed as well. | 1 | Applied and Interdisciplinary Chemistry |
Being the conjugate base of a strong acid (sulfuric acid), sulfate is not basic. It is more commonly a counterion in coordination chemistry. Tuttons salts, with the formula MM(SO)(HO) (M' = K, etc.; M = Fe, etc.), illustrate the ability of water to outcompete sulfate as a ligand for M. Similarly alums, such as chrome alum ([K(HO)][Cr(HO)][SO]), features with noncoordinated sulfate. In a related vein, some sulfato complexes confirmed by X-ray crystallography, convert to simple aquo complexes when dissolved in water. Copper(II) sulfate examplifies this behavior, sulfate is bonded to copper in the crystal but dissociates upon dissolution. | 0 | Theoretical and Fundamental Chemistry |
The velocity can be expressed in terms of the stream function as
where is the rotation matrix corresponding to a anticlockwise rotation about the positive axis. Solving the above equation for produces the equivalent form
From these forms it is immediately evident that the vectors and are
* perpendicular:
* of the same length: .
Additionally, the compactness of the rotation form facilitates manipulations (e.g., see Condition of existence). | 1 | Applied and Interdisciplinary Chemistry |
The Academy of Nutrition and Dietetics (AND) provides clinical guidance for preparing a subject for RMR measures, in order to mitigate possible confounding factors from feeding, stressful physical activities, or exposure to stimulants such as caffeine or nicotine:
Further, the correct use of a well-maintained indirect calorimeter includes achieving a natural and steady breathing pattern in order to reveal oxygen consumption and carbon dioxide production rates under a reproducible resting condition. Indirect calorimetry is considered the gold-standard method to measure RMR. Indirect calorimeters are usually found in laboratory and clinical settings, but technological advancements are bringing RMR measurement to free-living conditions. | 1 | Applied and Interdisciplinary Chemistry |
PBr evolves corrosive HBr, which is toxic, and reacts violently with water and alcohols.
:PBr + 3 HO → HPO + 3 HBr
In reactions that produce phosphorous acid as a by-product, when working up by distillation be aware that this can decompose above about 160 °C to give phosphine which can cause explosions in contact with air. | 0 | Theoretical and Fundamental Chemistry |
The stable compound cyanamide, whose minor tautomer is carbodiimide, is an isomer of diazomethane. Less stable but still isolable isomers of diazomethane include the cyclic 3H-diazirine and isocyanoamine (isodiazomethane). In addition, the parent nitrilimine has been observed under matrix isolation conditions.
<br /> | 0 | Theoretical and Fundamental Chemistry |
Physical properties of interest to materials science among perovskites include superconductivity, magnetoresistance, ionic conductivity, and a multitude of dielectric properties, which are of great importance in microelectronics and telecommunication. They are also some interests for scintillator as they have large light yield for radiation conversion. Because of the flexibility of bond angles inherent in the perovskite structure there are many different types of distortions which can occur from the ideal structure. These include tilting of the octahedra, displacements of the cations out of the centers of their coordination polyhedra, and distortions of the octahedra driven by electronic factors (Jahn-Teller distortions). The financially biggest application of perovskites is in ceramic capacitors, in which BaTiO is used because of its high dielectric constant. | 0 | Theoretical and Fundamental Chemistry |
The difficulty in the production of heavy Rydberg systems arises in finding an energetic pathway by which a molecule can be excited with just the right energy to form an ion pair, without sufficient internal energy to cause autodissociation (a process analogous to autoionization in atoms) or rapid dissociation due to collisions or local fields.
Currently production of heavy Rydberg systems relies on complex vacuum ultra-violet (so called because it is strongly absorbed in air and requires the entire system to be enclosed within a vacuum chamber) or multi-photon transitions (relying on absorption of multiple photons almost simultaneously), both of which are rather inefficient and result in systems with high internal energy. | 0 | Theoretical and Fundamental Chemistry |
The text is attributed to Zheng Yin, an alchemist from the 3rd century who purportedly taught Ge Hong, but the bulk of the text appears to have been written during the 9th century. | 1 | Applied and Interdisciplinary Chemistry |
The post-bioprinting process is necessary to create a stable structure from the biological material. If this process is not well-maintained, the mechanical integrity and function of the 3D printed object is at risk. To maintain the object, both mechanical and chemical stimulations are needed. These stimulations send signals to the cells to control the remodeling and growth of tissues. In addition, in recent development, bioreactor technologies have allowed the rapid maturation of tissues, vascularization of tissues and the ability to survive transplants.
Bioreactors work in either providing convective nutrient transport, creating microgravity environments, changing the pressure causing solution to flow through the cells, or adding compression for dynamic or static loading. Each type of bioreactor is ideal for different types of tissue, for example compression bioreactors are ideal for cartilage tissue. | 1 | Applied and Interdisciplinary Chemistry |
Charge-transfer interactions are also important in protein stabilization and surface interaction. In general donor-acceptor processes, one can think of excess electron density being present which can be donated to an electrophilic species. In aqueous media, these solute interactions are primarily due to pi orbital electron effects. | 1 | Applied and Interdisciplinary Chemistry |
The BET theory can be derived similarly to the Langmuir theory, but by considering multilayered gas molecule adsorption, where it is not required for a layer to be completed before an upper layer formation starts. Furthermore, the authors made five assumptions:
# Adsorptions occur only on well-defined sites of the sample surface (one per molecule)
# The only molecular interaction considered is the following one: a molecule can act as a single adsorption site for a molecule of the upper layer.
# The uppermost molecule layer is in equilibrium with the gas phase, i.e. similar molecule adsorption and desorption rates.
# The desorption is a kinetically limited process, i.e. a heat of adsorption must be provided:
#* these phenomena are homogeneous, i.e. same heat of adsorption for a given molecule layer.
#* it is E for the first layer, i.e. the heat of adsorption at the solid sample surface
#* the other layers are assumed similar and can be represented as condensed species, i.e. liquid state. Hence, the heat of adsorption is E is equal to the heat of liquefaction.
# At the saturation pressure, the molecule layer number tends to infinity (i.e. equivalent to the sample being surrounded by a liquid phase)
Consider a given amount of solid sample in a controlled atmosphere. Let θ be the fractional coverage of the sample surface covered by a number i of successive molecule layers. Let us assume that the adsorption rate R for molecules on a layer (i-1) (i.e. formation of a layer i) is proportional to both its fractional surface θ and to the pressure P, and that the desorption rate R on a layer i is also proportional to its fractional surface θ:
where k and k are the kinetic constants (depending on the temperature) for the adsorption on the layer (i−1) and desorption on layer i, respectively. For the adsorptions, these constants are assumed similar whatever the surface.
Assuming an Arrhenius law for desorption, the related constants can be expressed as
where E is the heat of adsorption, equal to E at the sample surface and to E otherwise.
Consider some substance A. The adsorption of A onto an available surface site produces a new site on the first layer. In summary,
Extending this to higher order layers one obtains
and similarly
Denoting the activity of the number of available sites of the th layer with and the partial pressure of A with , the last equilibrium can be written
It follows that the coverage of the first layer can be written
and that the coverage of the second layer can be written
Realising that the adsorption of A onto the second layer is equivalent to adsorption of A onto its own liquid phase, the rate constant for should be the same, which results in the recursion
In order to simplify some infinite summations, let and let . Then the th layer coverage can written
if . The coverage of any layer is defined as the relative number of available sites. An alternative definition, which leads to a set of coverage's that are numerically to those resulting from the original way of defining surface coverage, is that denotes the relative number of sites covered by only adsorbents. Doing so it is easy to see that the total volume of adsorbed molecules can be written as the sum
where is the molecular volume. Employing the fact that this sum is the first derivative of a geometric sum, the volume becomes
Since the total coverage of a mono-layer must be unity, the full mono-layer coverage must be
In order to properly make the substitution for , the restriction forces us to take the zeroth contribution outside the summation, resulting in
Lastly, defining the excess coverage as , the excess volume relative to the volume of an adsorbed mono-layer becomes
where the last equality was obtained by making use of the series expansions presented above. The constant must be interpreted as the relative binding affinity the substance A has towards a surface, relative to its own liquid. If then the initial part of the isotherm will be reminiscent of the Langmuir isotherm which reaches a plateau at full mono-layer coverage, whereas means the mono-layer will have a slow build-up. Another thing to note is that in order for the geometric substitutions to hold, . The isotherm above exhibits a singularity at . Since one can write , implying that . This means that must be true, ultimately resulting in . | 0 | Theoretical and Fundamental Chemistry |
Mutations in fumarate hydratase are found among patients suffering from kidney cancers, and mutations in succinate dehydrogenase were found in patients with pheochromocytoma and paragangliomas. These mutations cause a disruption of the TCA cycle with the accumulation of fumarate or succinate, both of which can inhibit dioxygenases or prolyl hydrolases that mediate the degradation of HIF proteins. HIF-1 could be elevated under aerobic conditions downstream from activated PI3K, which stimulates the synthesis of HIF-1. Loss of the tumor suppressor VHL in kidney cancer also stabilizes HIF-1, permitting it to activate glycolytic genes, which are normally activated by HIF-1 under hypoxic conditions. HIF1 then would activate the pyruvate dehydrogenase kinase (PDKs), which inactivate the mitochondrial pyruvate dehydrogenase complex. It reduces the flow of glucose-derived pyruvate into the tricarboxylic acid (citric acid cycle or TCA cycle). This reduction in pyruvate flux into the TCA cycle decreases the rate of oxidative phosphorylation and oxygen consumption, reinforcing the glycolytic phenotype and sparing oxygen under hypoxic conditions. | 1 | Applied and Interdisciplinary Chemistry |
In addition to numerous treatises in the Annales de Chimie et de Physique, he published Traité de chimie générale (7 vols., 3rd ed. 1862-65). The Encyclopédie Chimique, a work in 10 volumes, upon which he was engaged for thirteen years, was prepared by him in collaboration with several other scientists, and was completed in 1894. | 0 | Theoretical and Fundamental Chemistry |
In condensed matter physics and crystallography, the static structure factor (or structure factor for short) is a mathematical description of how a material scatters incident radiation. The structure factor is a critical tool in the interpretation of scattering patterns (interference patterns) obtained in X-ray, electron and neutron diffraction experiments.
Confusingly, there are two different mathematical expressions in use, both called structure factor. One is usually written ; it is more generally valid, and relates the observed diffracted intensity per atom to that produced by a single scattering unit. The other is usually written or and is only valid for systems with long-range positional order — crystals. This expression relates the amplitude and phase of the beam diffracted by the planes of the crystal ( are the Miller indices of the planes) to that produced by a single scattering unit at the vertices of the primitive unit cell. is not a special case of ; gives the scattering intensity, but gives the amplitude. It is the modulus squared that gives the scattering intensity. is defined for a perfect crystal, and is used in crystallography, while is most useful for disordered systems. For partially ordered systems such as crystalline polymers there is obviously overlap, and experts will switch from one expression to the other as needed.
The static structure factor is measured without resolving the energy of scattered photons/electrons/neutrons. Energy-resolved measurements yield the dynamic structure factor. | 0 | Theoretical and Fundamental Chemistry |
These contrasting effects reveal the importance of the endocannabinoid system in regulating anxiety-dependent behavior. Results suggest that glutamatergic cannabinoid receptors are not only responsible for mediating aggression, but produce an anxiolytic-like function by inhibiting excessive arousal: excessive excitation produces anxiety that limited the mice from exploring both animate and inanimate objects. In contrast, GABAergic neurons appear to control an anxiogenic-like function by limiting inhibitory transmitter release. Taken together, these two sets of neurons appear to help regulate the organism's overall sense of arousal during novel situations. | 1 | Applied and Interdisciplinary Chemistry |
Many different affinity media exist for a variety of possible uses.
Briefly, they are (generalized) activated/functionalized that work as a functional spacer, support matrix, and eliminates handling of toxic reagents.
Amino acid media is used with a variety of serum proteins, proteins, peptides, and enzymes, as well as rRNA and dsDNA. Avidin biotin media is used in the purification process of biotin/avidin and their derivatives.
Carbohydrate bonding is most often used with glycoproteins or any other carbohydrate-containing substance; carbohydrate is used with lectins, glycoproteins, or any other carbohydrate metabolite protein. Dye ligand media is nonspecific but mimics biological substrates and proteins. Glutathione is useful for separation of GST tagged recombinant proteins. Heparin is a generalized affinity ligand, and it is most useful for separation of plasma coagulation proteins, along with nucleic acid enzymes and lipases
Hydrophobic interaction media are most commonly used to target free carboxyl groups and proteins.
Immunoaffinity media (detailed below) utilizes antigens and antibodies high specificity to separate; immobilized metal affinity chromatography is detailed further below and uses interactions between metal ions and proteins (usually specially tagged) to separate; nucleotide/coenzyme that works to separate dehydrogenases, kinases, and transaminases.
Nucleic acids function to trap mRNA, DNA, rRNA, and other nucleic acids/oligonucleotides. Protein A/G method is used to purify immunoglobulins.
Speciality media are designed for a specific class or type of protein/co enzyme; this type of media will only work to separate a specific protein or coenzyme. | 0 | Theoretical and Fundamental Chemistry |
Mecillinam is used in the treatment of infections due to susceptible gram-negative bacteria, especially urinary tract infections which are most commonly caused by Escherichia coli. Mecillinam is active against most pathogenic Gram-negative bacteria, except Pseudomonas aeruginosa and some species of Proteus. Several studies have also found it to be as effective as other antibiotics for treating Staphylococcus saprophyticus infection, though it is Gram-positive, possibly because mecillinam reaches very high concentrations in urine.
Worldwide resistance to mecillinam in bacteria causing urinary tract infection has remained very low since its introduction; a 2003 study conducted in 16 European countries and Canada found resistance to range from 1.2% (Escherichia coli) to 5.2% (Proteus mirabilis). Another large study conducted in Europe and Brazil obtained similar results — 95.9% of E. coli strains, for instance, were sensitive to mecillinam. | 0 | Theoretical and Fundamental Chemistry |
Organic nitrites are prepared from alcohols and sodium nitrite in sulfuric acid solution. They decompose slowly on standing, the decomposition products being oxides of nitrogen, water, the alcohol, and polymerization products of the aldehyde. They are also prone to undergo homolytic cleavage to form alkyl radicals, the nitrite C–O bond being very weak (on the order of 40–50 kcal ⋅ mol). | 0 | Theoretical and Fundamental Chemistry |
HABs contain dense concentrations of organisms and appear as discolored water, often reddish-brown in color. It is a natural phenomenon, but the exact cause or combination of factors that result in a HAB event are not necessarily known. However, three key natural factors are thought to play an important role in a bloom - salinity, temperature, and wind. HABs cause economic harm, so outbreaks are carefully monitored. For example, the Florida Fish and Wildlife Conservation Commission provides an up-to-date status report on HABs in Florida. The Texas Parks and Wildlife Department also provides a status report. While no particular cause of HABs has been found, many different factors can contribute to their presence. These factors can include water pollution, which originates from sources such as human sewage and agricultural runoff.
The occurrence of HABs in some locations appears to be entirely natural (algal blooms are a seasonal occurrence resulting from coastal upwelling, a natural result of the movement of certain ocean currents) while in others they appear to be a result of increased nutrient pollution from human activities. The growth of marine phytoplankton is generally limited by the availability of nitrates and phosphates, which can be abundant in agricultural run-off as well as coastal upwelling zones. Other factors such as iron-rich dust influx from large desert areas such as the Sahara Desert are thought to play a major role in causing HAB events. Some algal blooms on the Pacific Coast have also been linked to occurrences of large-scale climatic oscillations such as El Niño events. | 0 | Theoretical and Fundamental Chemistry |
Organic selenocyanates are organoselenium compounds with the general formula RSeCN. They are generally colorless, air-stable solids or liquids with repulsive odors. In terms of structure, synthesis, and reactivity, selenocyanates and thiocyanates behave similarly. | 0 | Theoretical and Fundamental Chemistry |
*[https://web.archive.org/web/20160325031419/https://www.youtube.com/watch?v=gflKaMBrG-o]El Segundo Wind Tunnel, 9/2007 | 1 | Applied and Interdisciplinary Chemistry |
Alternative splicing is one of the most important components that show functional complexity of genome. Modified splicing has significant effect on the phenotype that is relevance to disease or drug metabolism. A change in splicing can be caused by modifying any of the components of the splicing machinery such as splice sites or splice enhancers or silencers. Modification in the alternative splicing site can lead to a different protein form which will show a different function. Humans use an estimated 100,000 different proteins or more, so some genes must be capable of coding for a lot more than just one protein. Alternative splicing occurs more frequently than was previously thought and can be hard to control; genes may produce tens of thousands of different transcripts, necessitating a new gene model for each alternative splice. | 1 | Applied and Interdisciplinary Chemistry |
A water distribution system consists of pipelines, storage facilities, pumps, and other accessories.
Pipelines laid within public right of way called water mains are used to transport water within a distribution system. Large diameter water mains called primary feeders are used to connect between water treatment plants and service areas. Secondary feeders are connected between primary feeders and distributors. Distributors are water mains that are located near the water users, which also supply water to individual fire hydrants. A service line is a small diameter pipe used to connect from a water main through a small tap to a water meter at users location. There is a service valve (also known as curb stop) on the service line located near street curb to shut off water to the users location.
Storage facilities, or distribution reservoirs, provide clean drinking water storage (after required water treatment process) to ensure the system has enough water to service in response to fluctuating demands (service reservoirs), or to equalize the operating pressure (balancing reservoirs). They can also be temporarily used to serve fire fighting demands during a power outage. The following are types of distribution reservoirs:
* Underground storage reservoir or covered finished water reservoir: An underground storage facility or large ground-excavated reservoir that is fully covered. The walls and the bottom of these reservoirs may be lined with impermeable materials to prevent ground water intrusion.
* covered finished water reservoir: A large ground-excavated reservoir that has adequate measures or lining to prevent surface water runoff and ground water intrusion but does not have a top cover. This type of reservoir is less desirable as the water will not be further treated before distribution and is susceptible to contaminants such as bird waste, animal and human activities, algal bloom, and airborne deposition.
* Surface reservoir (also known as ground storage tank and ground storage reservoir): A storage facility built on the ground with the wall lined with concrete, shotcrete, asphalt, or membrane. A surface reservoir is usually covered to prevent contamination. They are typically located in high elevation areas that have enough hydraulic head for distribution. When a surface reservoir at ground level cannot provide a sufficient hydraulic head to the distribution system, booster pumps will be required.
* Water tower (also known as elevated surface reservoir): An elevated water tank. A few common types are spheroid elevated storage tank, a steel spheroid tank on top of a small-diameter steel column; composite elevated storage tank, a steel tank on a large-diameter concrete column; and hydropillar elevated storage tanks, a steel tank on a large-diameter steel column. The space within the large column below the water tank can be used for other purposes such as multi-story office space and storage space. A main concern for using water towers in the water distribution system is the aesthetic of the area.
* Standpipe: A water tank that is a combination of ground storage tank and water tower. It is slightly different from an elevated water tower in that the standpipe allows water storage from the ground level to the top of the tank. The bottom storage area is called supporting storage, and the upper part which would be at the similar height of an elevated water tower is called useful storage.
* Sump: This is a contingency water storage facility that is not used to distribute water directly. It is typically built underground in a circular shape with a dome top above ground. The water from a sump will be pumped to a service reservoir when it is needed.
Storage facilities are typically located at the center of the service locations. Being at the central location reduces the length of the water mains to the services locations. This reduces the friction loss when water is transported over a water main. | 1 | Applied and Interdisciplinary Chemistry |
Peter Armbruster (born 25 July 1931) is a German physicist at the Gesellschaft für Schwerionenforschung (GSI) facility in Darmstadt, Germany, and is credited with co-discovering elements 107 (bohrium), 108 (hassium), 109 (meitnerium), 110 (darmstadtium), 111 (roentgenium), and 112 (copernicium) with research partner Gottfried Münzenberg.
Armbruster was born in Dachau, Bavaria. He studied physics at the Technical University of Stuttgart and Munich, and obtained his Ph.D. in 1961 under Heinz Maier-Leibnitz, Technical University of Munich. His major research fields are fission, interaction of heavy ions in matter and atomic physics with fission product beams at the Research Centre of Jülich (1965 to 1970). He was Senior Scientist at the Gesellschaft für Schwerionenforschung Darmstadt, GSI, from 1971 to 1996. From 1989 to 1992 he was research Director of the European Institut Laue-Langevin (ILL), Grenoble. Since 1996 he has been involved in a project on incineration of nuclear waste by spallation and fission reactions.
He was affiliated as professor to the University of Cologne (1968) and the Darmstadt University of Technology since 1984.
He has received many awards for his work, including the Max Born Medal and Prize awarded by the Institute of Physics and the Deutsche Physikalische Gesellschaft in 1988, and the Stern-Gerlach Medal awarded by the Deutsche Physikalische Gesellschaft in 1997. The American Chemical Society honoured Peter Armbruster 1997 as one of few non-Americans with the Nuclear Chemistry Award. | 1 | Applied and Interdisciplinary Chemistry |
Single-molecule techniques impacted optics, electronics, biology, and chemistry. In the biological sciences, the study of proteins and other complex biological machinery was limited to ensemble experiments that nearly made impossible the direct observation of their kinetics. For example, it was only after single molecule fluorescence microscopy was used to study kinesin-myosin pairs in muscle tissue that direct observation of the walking mechanisms were understood. These experiments, however, have for the most part been limited to in vitro studies, as useful techniques for live cell imaging have yet to be fully realized. The promise of single molecule in vivo imaging, however, brings with it an enormous potential to directly observe bio-molecules in native processes. These techniques are often targeted for studies involving low-copy proteins, many of which are still being discovered. These techniques have also been extended to study areas of chemistry, including the mapping of heterogeneous surfaces. | 0 | Theoretical and Fundamental Chemistry |
* Pacey, A. J. & Fisher, S. J. (1967) "Daniel Bernoulli and the vis viva of compressed air", The British Journal for the History of Science 3 (4), p. 388–392,
* British Transport Commission (1957) Handbook for Railway Steam Locomotive Enginemen, London : B.T.C., p. 81, (facsimile copy publ. Ian Allan (1977), ) | 0 | Theoretical and Fundamental Chemistry |
Copy number analysis is the process of analyzing data produced by a test for DNA copy number variation in an organism's sample. One application of such analysis is the detection of chromosomal copy number variation that may cause or may increase risks of various critical disorders. Copy number variation can be detected with various types of tests such as fluorescent in situ hybridization, comparative genomic hybridization and with high-resolution array-based tests based on array comparative genomic hybridization (or aCGH), SNP array technologies and high resolution microarrays that include copy number probes as well an SNPs. Array-based methods have been accepted as the most efficient in terms of their resolution and high-throughput nature and the highest coverage (choose an array with over 2 million probes) and they are also referred to as virtual karyotype. Data analysis for an array-based DNA copy number test can be very challenging though due to very high volume of data that come out of an array platform.
BAC (Bacterial Artificial Chromosome) arrays were historically the first microarray platform to be used for DNA copy number analysis. This platform is used to identify gross deletions or amplifications in DNA. Such anomalies for example are common in cancer and can be used for diagnosis of many developmental disorders. Data produced by such platforms are usually low to medium resolution in terms of genome coverage. Usually, log-ratio measurements are produced by this technology to represent deviation of patient's copy number state from normal. Such measurements then are studied and those that significantly differ from zero value are announced to represent a part of a chromosome with an anomaly (an abnormal copy number state). Positive log-ratios indicate a region of DNA copy number gain and negative log-ratio values mark a region of DNA copy number loss. Even a single data point can be declared an indication of a copy number gain or a copy number loss in BAC arrays. | 1 | Applied and Interdisciplinary Chemistry |
N-Sulfinyl imines (N-sulfinylimines, sulfinimines, thiooxime S-oxides) are a class of imines bearing a sulfinyl group attached to nitrogen. These imines display useful stereoselectivity reactivity and due to the presence of the chiral electron withdrawing N-sulfinyl group. They allow 1,2-addition of organometallic reagents to imines. The N-sulfinyl group exerts powerful and predictable stereodirecting effects resulting in high levels of asymmetric induction. Racemization of the newly created carbon-nitrogen stereo center is prevented because anions are stabilized at nitrogen (i.e., the sulfinyl group is a versatile amine protection group). The sulfinyl chiral auxiliary is readily removed by simple acid hydrolysis. The addition of organometallic reagents to N-sulfinyl imines is the most reliable and versatile method for the asymmetric synthesis of amine derivatives. These building blocks have been employed in the asymmetric synthesis of numerous biologically active compounds. | 0 | Theoretical and Fundamental Chemistry |
Heat cramps, a type of heat illness, are muscle spasms that result from loss of large amount of salt and water through exercise. Heat cramps are associated with cramping in the abdomen, arms and calves. This can be caused by inadequate consumption of fluids or electrolytes. Heavy sweating causes heat cramps, especially when the water is replaced without also replacing salt or potassium.
Although heat cramps can be quite painful, they usually don't result in permanent damage, though they can be a symptom of heat stroke or heat exhaustion. Heat cramps can indicate a more severe problem in someone with heart disease or if they last for longer than an hour.
In order to prevent them, one may drink electrolyte solutions such as sports drinks during exercise or strenuous work or eat potassium-rich foods like bananas and apples. When heat cramps occur, the affected person should avoid strenuous work and exercise for several hours to allow for recovery. | 0 | Theoretical and Fundamental Chemistry |
As described in the applications section, spectrophotometry can be used in both qualitative and quantitative analysis of DNA, RNA, and proteins. Qualitative analysis can be used and spectrophotometers are used to record spectra of compounds by scanning broad wavelength regions to determine the absorbance properties (the intensity of the color) of the compound at each wavelength. One experiment that can demonstrate the various uses that visible spectrophotometry can have is the separation of β-galactosidase from a mixture of various proteins. Largely, spectrophotometry is best used to help quantify the amount of purification your sample has undergone relative to total protein concentration. By running an affinity chromatography, B-Galactosidase can be isolated and tested by reacting collected samples with Ortho-Nitrophenyl-β-galactoside (ONPG) and determining if the sample turns yellow. Following this testing the sample at 420 nm for specific interaction with ONPG and at 595 for a Bradford Assay the amount of purification can be assessed quantitatively. In addition to this spectrophotometry can be used in tandem with other techniques such as SDS-Page electrophoresis in order to purify and isolate various protein samples. | 0 | Theoretical and Fundamental Chemistry |
The methylation of certain CpG clusters (i.e. DNA areas high in cytosine and guanine) regulate the transcriptional activity of nearby genes. That is, the methylation of a cluster(s) regulates its nearby gene by blocking it from making mRNAs and thereby the proteins encoded by these mRNAs. Studies find that the CMTM5 gene in the DNA isolated from the blood of individuals with the autoimmune diseases of systemic lupus erythematosus and primary Sjögrens syndrome (i.e. Sjorgens syndrome not associated with other health problems or connective tissue diseases) is hyper-methylated at its CpG cluster(s) and thereby less active or inactive. On the other hand, the CpG cluster(s) controlling the CMTM5 gene in the blood of individuals with the autoimmune disease of rheumatoid arthritis are hypo-methylated and therefore highly active. These methylation changes, the studies suggest, regulate the function of immunologically active blood cells (and, perhaps, blood platelets) and thereby the development, maintenance, and/or worsening of the cited autoimmune diseases. Further studies are required to prove that these methylations contribute to the immunologic dysregulations occurring in these (and perhaps other) autoimmune diseases and can serve as clinical markers of disease severity and/or as therapeutic targets for controlling the diseases. | 1 | Applied and Interdisciplinary Chemistry |
geWorkbench (genomics Workbench) is an open-source software platform for integrated genomic data analysis. It is a desktop application written in the programming language Java. geWorkbench uses a component architecture. , there are more than 70 plug-ins available, providing for the visualization and analysis of gene expression, sequence, and structure data.
geWorkbench is the Bioinformatics platform of MAGNet, the National Center for the Multi-scale Analysis of Genomic and Cellular Networks, one of the 8 National Centers for Biomedical Computing funded through the NIH Roadmap (NIH Common Fund). Many systems and structure biology tools developed by MAGNet investigators are available as geWorkbench plugins. | 1 | Applied and Interdisciplinary Chemistry |
In chemistry, a sulfilimine (or sulfimide) is a type of chemical compound containing a sulfur-to-nitrogen bond which is often represented as a double bond (). In fact, a double bond violates the octet rule, and the bond may be considered a single bond with a formal charge of +1 on the sulfur and a formal charge of −1 on the nitrogen. The parent compound is sulfilimine , which is mainly of theoretical interest.
Examples include S,S-diphenylsulfilimine and sulfoximines  such as methylphenylsulfoximine: In the case of a sulfoximine, the bonds can be considered single bonds, with formal charges of −1 on both the oxygen and the nitrogen, and a formal charge of +2 on the sulfur. | 0 | Theoretical and Fundamental Chemistry |
An important early contribution was made by Pierre Prevost in 1791. Prevost considered that what is nowadays called the photon gas or electromagnetic radiation was a fluid that he called "free heat". Prevost proposed that free radiant heat is a very rare fluid, rays of which, like light rays, pass through each other without detectable disturbance of their passage. Prevost's theory of exchanges stated that each body radiates to, and receives radiation from, other bodies. The radiation from each body is emitted regardless of the presence or absence of other bodies.
Prevost in 1791 offered the following definitions (translated):
Prevost went on to comment that "The heat of several portions of space at the same temperature, and next to one another, is at the same time in the two species of equilibrium." | 0 | Theoretical and Fundamental Chemistry |
*Feedstock
**Microbial oil
***Oleaginous microorganism
**Palm oil
**Soybean oil
**Coconut oil
**Vegetable fats and oils
**Jatropha
**Animal fat
**Waste oil
Common feedstock used in biodiesel production include:
*Yellow grease (recycled vegetable oil)
*Vegetable oil fuel
*Tallow
Lignocellulose generates byproducts that act as enzyme inhibitors, such as acetic acid, furfural, formic acid, vanillin, and these chemical inhibitors affect cell growth.
Recycled oil is processed to remove impurities from cooking, storage, and handling, such as dirt, charred food, and water. Virgin oils are refined, but not to a food-grade level. Degumming to remove phospholipids and other plant matter is common, though refinement processes vary. Water is removed because its presence during base-catalyzed transesterification results in the saponification (hydrolysis) of the triglycerides, producing soap instead of biodiesel.
A sample of the cleaned feedstock is then tested via titration against a standardized base solution, to determine the concentration of free fatty acids present in the vegetable oil sample. The acids are then either removed (typically through neutralization), or are esterified to produce biodiesel (or glycerides). | 0 | Theoretical and Fundamental Chemistry |
Levonorgestrel is a weak agonist of the androgen receptor (AR), the main biological target of the androgen sex hormone testosterone. It is a weakly androgenic progestin and in women may cause androgenic biochemical changes and side effects such as decreased sex hormone-binding globulin (SHBG) levels, decreased cholesterol levels, weight gain, and acne.
In combination with a potent estrogen like ethinylestradiol however, all contraceptives containing androgenic progestins are negligibly androgenic in practice and in fact can be used to treat androgen-dependent conditions like acne and hirsutism in women. This is because ethinylestradiol causes a marked increase in SHBG levels and thereby decreases levels of free and hence bioactive testosterone, acting as a functional antiandrogen. Nonetheless, contraceptives containing progestins that are less androgenic increase SHBG levels to a greater extent and may be more effective for such indications. Levonorgestrel is currently the most androgenic progestin that is used in contraceptives, and contraceptives containing levonorgestrel may be less effective for androgen-dependent conditions relative to those containing other progestins that are less androgenic. | 0 | Theoretical and Fundamental Chemistry |
Snow and ice sublime gradually at temperatures below the solid-liquid boundary (melting point) (generally 0 °C), and at partial pressures below the triple point pressure of , at a low rate. In freeze-drying, the material to be dehydrated is frozen and its water is allowed to sublime under reduced pressure or vacuum. The loss of snow from a snowfield during a cold spell is often caused by sunshine acting directly on the upper layers of the snow. Sublimation of ice is a factor to the erosive wear of glacier ice, also called ablation in glaciology. | 0 | Theoretical and Fundamental Chemistry |
Huang joined the Shanghai Institute of Organic Chemistry (SIOC), Chinese Academy of Sciences in 1955. In 1958, he responded to the demand of Chinese defense industry, stopped his established organic natural product research work and pursued research in the field of organofluorine chemistry. Under his leadership, the major base for organofluorine chemistry in China was established at the SIOC.
Huang discovered the sulfinatodehalogenation reaction in 1981, which converts perfluoroalkyl halides to the corresponding perfluoroalkanesulfinates with sulfinatodehalogenation reagents such as sodium dithionite. He and his students identified this reaction as a single electron transfer reaction. This reaction opens a new and practical way for perfluoroalkylation of unsaturated substrates such as alkenes alkynes and aromatics compounds with sulfinatodehalogenation reagents. This reaction is well documented internationally and he won the Second-class Award of National Natural Science in 1986.
Huang has published more than 200 research papers and has mentored twenty Ph.D. candidates, including the first Ph.D. in Organic Chemistry in Mainland China. He was the first one in China (1958) to introduce NMR and IR applications in organic chemistry.
He was elected as an academician of the Chinese Academy of Sciences in 1980. Huang was deputy director of SIOC (1978-1984) and director from 1984-1987. SIOC is the major Chinese chemistry research center and the place edits and publishes several major Chinese academic journals of chemistry.
Huang was the founder and chief editor of the Chinese Journal of Chemistry. He was elected as President of the Chinese Chemical Society (1986-1990).
Huang was in the first delegation from the Chinese chemist community to visit USA in 1977 and he made great efforts to establish the good relationship in exchange of scholars and visiting between Chinese and American chemists.
Huang received broad recognition from international chemistry community. He was elected as bureau member of IUPAC (1985-1993). He was awarded the Moissan Medal in 1986 at the conference "Centenary of the Discovery of Fluorine" in Paris. He was the co-chairman of 17th international symposium of fluorine chemistry in 2003. | 0 | Theoretical and Fundamental Chemistry |
Iminium ions are potent electrophiles useful for generating C-C bonds in complex molecules. However, the condensation of amines with carbonyl compounds to form iminium ions is often unfavorable, sometimes requiring harsh dehydrating conditions. Thus, alternative methods for iminium ion generation, particularly by oxidation from the corresponding amine, are a valuable synthesis tool. Iminium ions can be generated from activated amines using Ir(dtbbpy)(ppy)PF as a photoredox catalyst. This transformation is proposed to occur by oxidation of the amine to the aminium radical cation by the excited photocatalyst. This is followed by hydrogen atom transfer to a superstoichimetric oxidant, such as trichloromethyl radical (CCl to form the iminium ion). The iminium ion is then quenched by reaction with a nucleophile. Related transformations of amines with a wide variety of other nucleophiles have been investigated, such as cyanide (Strecker reaction), silyl enol ethers (Mannich reaction), dialkylphosphates, allyl silanes (aza-Sakurai reaction), indoles (Friedel-Crafts reaction), and copper acetylides.
Similar photoredox generation of iminium ions has furthermore been achieved using purely organic photoredox catalysts, such as Rose Bengal and Eosin Y.
An asymmetric variant of this reaction utilizes acyl nucleophile equivalents generated by N-heterocyclic carbene catalysis. This reaction method sidesteps the problem of poor enantioinduction from chiral photoredox catalysts by moving the source of enantioselectivity to the N-heterocyclic carbene. | 0 | Theoretical and Fundamental Chemistry |
The European Coil Coating Association (ECCA) is an international non-profit association dedicated to the diffusion of the use of coil and/or sheet coated metal. | 1 | Applied and Interdisciplinary Chemistry |
Each element has a specific set of chemical properties as a consequence of the number of electrons present in the neutral atom, which is Z (the atomic number). The configuration of these electrons follows from the principles of quantum mechanics. The number of electrons in each elements electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. Hence, it is the atomic number alone that determines the chemical properties of an element; and it is for this reason that an element can be defined as consisting of any' mixture of atoms with a given atomic number. | 0 | Theoretical and Fundamental Chemistry |
The first SGS model developed was the Smagorinsky–Lilly SGS model, which was developed by Smagorinsky and used in the first LES simulation by Deardorff. It models the eddy viscosity as:
where is the grid size and is a constant.
This method assumes that the energy production and dissipation of the small scales are in equilibrium - that is, . | 1 | Applied and Interdisciplinary Chemistry |
Extrusion-based printing is a very common technique within the field of 3D printing which entails extruding, or forcing, a continuous stream of melted solid material or viscous liquid through a sort of orifice, often a nozzle or syringe. When it comes to extrusion based bioprinting, there are four main types of extrusion. These are pneumatic driven, piston driven, screw driven and eccentric screw driven (also known as progressing cavity pump). Each extrusion method has their own advantages and disadvantages. Pneumatic extrusion uses pressurized air to force liquid bioink through a depositing agent. Air filters are commonly used to sterilize the air before it is used, to ensure air pushing the bioink is not contaminated. Piston driven extrusion utilizes a piston connected to a guide screw. The linear motion of the piston squeezes material out of the nozzle. Screw driven extrusion uses an auger screw to extrude material using rotational motion. Screw driven devices allow for the use of higher viscosity materials and provide more volumetric control. Eccentric screw driven systems allow for a much more precise deposition of low to high viscosity materials due to the self-sealing chambers in the extruder. Once printed, many materials require a crosslinking step to achieve the desired mechanical properties for the construct, which can be achieved for example with the treatment of chemical agents or photo-crosslinkers.
Direct extrusion is one of the most common extrusion-based bioprinting techniques, wherein the pressurized force directs the bioink to flow out of the nozzle, and directly print the scaffold without any necessary casting. The bioink itself for this approach can be a blend of polymer hydrogels, naturally derived materials such as collagen, and live cells suspended in the solution. In this manner, scaffolds can be cultured post-print and without the need for further treatment for cellular seeding. Some focus in the use of direct printing techniques is based upon the use of coaxial nozzle assemblies, or coaxial extrusion. The coaxial nozzle setup enables the simultaneous extrusion of multiple material bioinks, capable of making multi-layered scaffolds in a single extrusion step. The development of tubular structures has found the layered extrusion achieved via these techniques desirable for the radial variability in material characterization that it can offer, as the coaxial nozzle provides an inner and outer tube for bioink flow. Indirect extrusion techniques for bioprinting rather require the printing of a base material of cell-laden hydrogels, but unlike direct extrusion contains a sacrificial hydrogel that can be trivially removed post-printing through thermal or chemical extraction. The remaining resin solidifies and becomes the desired 3D-printed construct. | 1 | Applied and Interdisciplinary Chemistry |
CDE is defined by the United States Nuclear Regulatory Commission in Title 10, Section 20.1003, of the Code of Federal Regulations (10 CFR 20.1003), such that "The Committed dose equivalent, CDE (H,50) is the dose to some specific organ or tissue of reference (T) that will be received from an intake of radioactive material by an individual during the 50-year period following the intake".
"The calculation of the committed effective dose equivalent (CEDE) begins with the determination of the equivalent dose, H, to a tissue or organ, T. Where D,R is the absorbed dose in rads (one gray, an SI unit, equals 100 rads) averaged over the tissue or organ, T, due to radiation type, R, and W is the radiation weighting factor. The unit of equivalent dose is the rem (sievert, in SI units)." | 0 | Theoretical and Fundamental Chemistry |
The use of thermal mass is the most challenging in this environment where night temperatures remain elevated. Its use is primarily as a temporary heat sink. However, it needs to be strategically located to prevent overheating. It should be placed in an area that is not directly exposed to solar gain and also allows adequate ventilation at night to carry away stored energy without increasing internal temperatures any further. If to be used at all it should be used in judicious amounts and again not in large thicknesses. | 0 | Theoretical and Fundamental Chemistry |
Similar to the dissection procedure, animals are injected with a low dose of a radiolabelled compound. At the chosen time points after injection, PET or SPECT images are acquired, typically also a CT or MR image for anatomical reference. The radioactivity concentration is measured from the PET or SPECT images for the various organs of interest. This may include measuring the volume of these organs e.g. from the CT image (rather than weighing the organs as in the dissection procedure) or assessing the radioactivity concentration in a representative part of the organ. Normalizing the tissue radioactivity concentrations to the injected dose gives values in units of percent of the injected dose per milliliter of organ or biological tissue.
A benefit of imaging is that the animals can be anaesthetized for imaging for several or all the required time points, that is few animals are required for this procedure and all of them are kept alive. This is considered a non-invasive procedure. In addition, the procedure is in essence the same as for medical diagnostic imaging in the clinic with two main differences: (1) novel compounds under development may be injected into animals subject to scrutiny and approval of the detailed experimental plan while clinicians can only inject radiolabelled compounds that had been tested rigorously and approved for use in humans; (2) animals usually need to be anaesthetized for the duration of the scan (on the order of minutes) while humans are awake and simply need to stay still during the scan. | 1 | Applied and Interdisciplinary Chemistry |
Atmospheric dispersion, or diffusion, studies how pollutants are mixed in the environment. There are many factors included in this modeling process, such as which level of atmosphere(s) the mixing is taking place, the stability of the environment and what type of contaminant and source is being mixed. The Eulerian and Lagrangian (discussed below) models have both been used to simulate atmospheric diffusion, and are important for a proper understanding of how pollutants react and mix in different environments. Both of these models take into account both vertical and horizontal wind, but additionally integrate Fickian diffusion theory to account for turbulence. While these methods have to use ideal conditions and make numerous assumptions, at this point in time, it is difficult to better calculate the effects of turbulent diffusion on pollutants. Fickian diffusion theory and further advancements in research on atmospheric diffusion can be applied to model the effects that current emission rates of pollutants from various sources have on the atmosphere. | 1 | Applied and Interdisciplinary Chemistry |
Rather than using cylindrical rotors, spinning spheres can be spun stably at the magic angle, which can be used to increase the filling factor of the coils, hence improve the sensitivity. Magic angle spinning spheres allow stable MAS with faster spinning rates. | 0 | Theoretical and Fundamental Chemistry |
Certain species of hornwort are the only land plants which are known to have a biophysical CCM involving concentration of carbon dioxide within pyrenoids in their chloroplasts. | 0 | Theoretical and Fundamental Chemistry |
The following table lists pharmaceuticals that have been available in both racemic and single-enantiomer form. These single-enantiomer drug switched from the respective racemic drug are referred to as chiral switch.
The following are cases where the individual enantiomers have markedly different effects:
*Thalidomide: Thalidomide is racemic. One enantiomer is effective against morning sickness, whereas the other is teratogenic. However, the enantiomers are converted into each other in vivo. As a result, dosing with a single-enantiomer form of the drug will still lead to both the enantiomers eventually being present in the patients serum and thus would not prevent adverse effects—at best, it might reduce them if the rate of in vivo' conversion can be slowed.
*Ethambutol: Whereas the (S,S)-(+)-enantiomer is used to treat tuberculosis, the (R,R)-(–)-ethambutol may cause blindness.
*Steroid receptor sites also show stereoisomer specificity.
*Penicillin's activity is stereodependent. The antibiotic must mimic the -alanine chains that occur in the cell walls of bacteria in order to react with and subsequently inhibit bacterial transpeptidase enzyme.
*Propranolol: -propranolol is a powerful adrenoceptor antagonist, whereas -propranolol is not. However, both have local anesthetic effect.
*Methorphan: The -isomer of methorphan, levomethorphan, is a potent opioid analgesic, while the -isomer, dextromethorphan, is a dissociative cough suppressant.
*Carvedilol: (S)-(–)-isomer interacts with adrenoceptors with 100 times greater potency as β adrenoreceptor blocker than (R)-(+)-isomer. However, both the isomers are approximately equipotent as α adrenoreceptor blockers.
*Amphetamine and methamphetamine: The -isomers of these drugs are strong central nervous system (CNS) stimulants, while the -isomers lack appreciable CNS stimulant effects, but instead stimulate the peripheral nervous system. For this reason, the -isomer of methamphetamine is available as an over-the-counter nasal inhaler in some countries, while the -isomer is banned from medical use in all but a few countries in the world, and highly regulated in those countries which do allow it to be used medically.
*Ketamine: This drug is available as a mixture of both (S)-(+)-ketamine, also known as esketamine, and (R)-(–)-ketamine, also known as arketamine. Pure esketamine is also available. The two have different dissociative and hallucinogenic properties, with esketamine being more potent in isolation as a dissociative. The two enantiomers have inverse effects on the rate of glucose metabolism in the frontal cortex.
*Dihydroxy-3, 4 phenylalanine (Dopa): Dopa is a racemic mixture where one enantiomer, L-Dopa, is used as a treatment for Parkinson's Disease, and the other enantiomer, D-Dopa is considered to be toxic. D-Dopa can cause headaches, abdominal pains, nausea, vomiting, and dizziness. | 0 | Theoretical and Fundamental Chemistry |
Hydrogenography is a combinatorial method based on the observation of optical changes on the metal surface by hydrogen absorption. The method allows the examination of thousands of combinations of alloy samples in a single batch. | 0 | Theoretical and Fundamental Chemistry |
Gastrointestinal organoids refer to organoids that recapitulate structures of the gastrointestinal tract. The gastrointestinal tract arises from the endoderm, which during development forms a tube that can be divided in three distinct regions, which give rise to, along with other organs, the following sections of the gastrointestinal tract:
:# The foregut gives rise to the oral cavity and the stomach
:# The midgut gives rise to the small intestines and the ascending colon
:# The hindgut gives rise to the rectum and the rest of the colon
Organoids have been created for the following structures of the gastrointestinal tract: | 1 | Applied and Interdisciplinary Chemistry |
To help mitigate inbreeding depression for two endangered species, the Black-footed ferret(Mustela nigripes), Revive & Restore facilitates on-going efforts to clone individuals from historic cell lines stored at the San Diego Zoo Wildlife Alliance Frozen Zoo. The program seeks to restore genetic variation lost from the living gene pool.
On December 10, 2020, the world's first cloned black-footed ferret was born. This ferret, named Elizabeth Ann, marked the first time a U.S. endangered species was successfully cloned.
The cells of two 1980s wild-caught black-footed ferrets that never bred in captivity were preserved in the San Diego Wildlife Alliance Frozen Zoo. One of them was cloned to increase genetic diversity in this species in December 2020. More clones of both are planned. They will initially be bred separately from the non-cloned population. | 1 | Applied and Interdisciplinary Chemistry |
Saccharides are a food source rich in energy. Large polymers such as starch are partially hydrolyzed in the mouth by the enzyme amylase before being cleaved further into sugars. Many mammals have seen great expansions in the copy number of the amylase gene. These duplications allow for the pancreatic amylase AMY2 to re-target to the salivary glands, allowing animals to detect starch by taste and to digest starch more efficiently and in higher quantities. This has happened independently in mice, rats, dogs, pigs, and most importantly, humans after the agricultural revolution.
Following the agricultural revolution 12,000 years ago, human diet began to shift more to plant and animal domestication in place of hunting and gathering. Starch has become a staple of the human diet.
Despite the obvious benefits, early humans did not possess salivary amylase, a trend that is also seen in evolutionary relatives of the human, such as chimpanzees and bonobos, who possess either one or no copies of the gene responsible for producing salivary amylase.
Like in other mammals, the pancreatic alpha-amylase AMY2 was duplicated multiple times. One event allowed it to evolve salivary specificity, leading to the production of amylase in the saliva (named in humans as AMY1). The 1p21.1 region of human chromosome 1 contains many copies of these genes, variously named AMY1A, AMY1B, AMY1C, AMY2A, AMY2B, and so on.
However, not all humans possess the same number of copies of the AMY1 gene. Populations known to rely more on saccharides have a higher number of AMY1 copies than human populations that, by comparison, consume little starch. The number of AMY1 gene copies in humans can range from six copies in agricultural groups such as European-American and Japanese (two high starch populations) to only two to three copies in hunter-gatherer societies such as the Biaka, Datog, and Yakuts.
The correlation that exists between starch consumption and number of AMY1 copies specific to population suggest that more AMY1 copies in high starch populations has been selected for by natural selection and considered the favorable phenotype for those individuals. Therefore, it is most likely that the benefit of an individual possessing more copies of AMY1 in a high starch population increases fitness and produces healthier, fitter offspring.
This fact is especially apparent when comparing geographically close populations with different eating habits that possess a different number of copies of the AMY1 gene. Such is the case for some Asian populations that have been shown to possess few AMY1 copies relative to some agricultural populations in Asia. This offers strong evidence that natural selection has acted on this gene as opposed to the possibility that the gene has spread through genetic drift.
Variations of amylase copy number in dogs mirrors that of human populations, suggesting they acquired the extra copies as they followed humans around. Unlike humans whose amylase levels depend on starch content in diet, wild animals eating a broad range of foods tend to have more copies of amylase. This may have to do with mainly detection of starch as opposed to digestion. | 1 | Applied and Interdisciplinary Chemistry |
As an actor, he played minor roles with Yvonne De Carlo in Ride the Pink Horse (1947), River Lady (1948) and Black Bart (1948).
He died in Los Angeles on 4 July 2002 at aged 90. | 1 | Applied and Interdisciplinary Chemistry |
The de Broglie wavelength of ions used in LEIS experiments is given as . Using a worst-case value of 500 eV for an He ion, we see λ is still only 0.006 Å, still well below the typical interatomic spacing of 2-3 Å. Because of this, the effects of diffraction are not significant in a normal LEIS experiment. | 0 | Theoretical and Fundamental Chemistry |
A main difficulty of DHR research and weak point of the p-i concept is the fact that it is cumbersome to demonstrate a p-i reactivity – namely that the T cell stimulation occurred due to non-covalent drug binding to immune receptors. In principle, a T cell mediated DHR was explained by p-i if the drug binding to the immune receptors was found to be labile. | 1 | Applied and Interdisciplinary Chemistry |
Hahn's 1950 paper showed that another method for generating spin echoes is to apply three successive 90° pulses. After the first 90° pulse, the magnetization vector spreads out as described above, forming what can be thought of as a "pancake" in the x-y plane. The spreading continues for a time , and then a second 90° pulse is applied such that the "pancake" is now in the x-z plane. After a further time a third pulse is applied and a stimulated echo is observed after waiting for a time after the last pulse. | 0 | Theoretical and Fundamental Chemistry |
The 2005 edition replaces their previous recommendations Nomenclature The Red Book of Inorganic Chemistry, IUPAC Recommendations 1990 (Red Book I), and "where appropriate" (sic) Nomenclature of Inorganic Chemistry II, IUPAC Recommendations 2000 (Red Book II).
The recommendations take up over 300 pages and the full text can be downloaded from IUPAC. Corrections have been issued.
Apart from a reorganisation of the content, there is a new section on organometallics and a formal element list to be used in place of electronegativity lists in sequencing elements in formulae and names. The concept of a preferred IUPAC name (PIN), a part of the revised blue book for organic compound naming, has not yet been adopted for inorganic compounds. There are however guidelines as to which naming method should be adopted. | 0 | Theoretical and Fundamental Chemistry |
The Earle K. Plyler Prize for Molecular Spectroscopy and Dynamics is a prize that has been awarded annually by the American Physical Society since 1977. The recipient is chosen for "notable contributions to the field of molecular spectroscopy and dynamics". The prize is named after Earle K. Plyler, who was a leading experimenter in the field of infrared spectroscopy; as of 2007 it is valued at $10,000. The prize is currently sponsored by the AIP Journal of Chemical Physics. | 0 | Theoretical and Fundamental Chemistry |
The gene early growth response protein 1 (EGR1) is an immediate early gene (IEG). EGR1 can rapidly be induced by neuronal activity. The defining characteristic of IEGs is the rapid and transient up-regulation—within minutes—of their mRNA levels independent of protein synthesis. In adulthood, EGR1 is expressed widely throughout the brain, maintaining baseline expression levels in several key areas of the brain including the medial prefrontal cortex, striatum, hippocampus and amygdala. This expression is linked to control of cognition, emotional response, social behavior and sensitivity to reward. EGR1 binds to DNA at sites with the motifs 5′-GCGTGGGCG-3′ and 5'-GCGGGGGCGG-3′ and these motifs occur primarily in promoter regions of genes. The short isoform TET1s is expressed in the brain. EGR1 and TET1s form a complex mediated by the C-terminal regions of both proteins, independently of association with DNA. EGR1 recruits TET1s to genomic regions flanking EGR1 binding sites. In the presence of EGR1, TET1s is capable of locus-specific demethylation and activation of the expression of downstream genes regulated by EGR1. | 1 | Applied and Interdisciplinary Chemistry |
This stage, in which pancreatic enzymes are administered, can be useful in identifying patients with pancreatic insufficiency. The physician will give 3 days of pancreatic enzymes followed by repeating the test to check if radio-labeled Vitamin B12 would be detected in urine. | 1 | Applied and Interdisciplinary Chemistry |
Gain of function mutation was first discovered in patients with chronic mucocutaneous candidiasis (CMC). This disease is characteristic with its symptoms as persistent infections of the skin, mucosae - oral or genital and nails infections caused by Candida, mostly Candida albicans. CMC may very often result from primary immunodeficiency. Patients with CMC often suffer also with bacterial infections (mostly Staphylococcus aureus), also with infections of the respiratory system and skin. In these patients we can also find viral infections caused mostly by Herpesviridae, that also affect the skin. The mycobacterial infections are often caused by Mycobacterium tuberculosis or environmental bacteria. Very common are also autoimmune symptoms like type 1 diabetes, cytopenia, regression of the thymus or systemic lupus erythematosus. When T-cell deficient, these autoimmune díseases are very common. CMC was also reported as a common symptom in patients with hyper immunoglobulin E syndrome (hyper-IgE) and with autoimmune polyendocrine syndrome type I. There was reported an interleukin 17A role, because of low levels of IL-17A producing T-cells in CMC patients.
With various genomic and genetic methods was discovered, that a heterozygous gain of function mutation of STAT1 is a cause of more than a half CMC cases. This mutation is caused by defect in the coiled-coil domain, domain that binds DNA, N-terminal domain or SH2 domain. Because of this there is increased phosphorylation because of impossible dephosphorylation in nucleus. These processes are dependent on cytokines like interferon alpha or beta, interferon gamma or interleukin 27. As mentioned above, low levels of interleukin 17A were observed, therefore impaired the Th17 polarization of the immune response.
Patients with STAT1 gain of function mutation and CMC poorly or not at all respond to treatment with azole drugs such as Fluconazole, Itraconazole or Posaconazole. Besides common viral and bacterial infections, these patients develop autoimmunities or even carcinomas. It is very complicated to find a treatment because of various symptoms and resistances, inhibitors of JAK/STAT pathway such as Ruxolitinib are being tested and are a possible choice of treatment for these patients. | 1 | Applied and Interdisciplinary Chemistry |
Because of its fast growth, Eucalyptus occidentalis was mostly used in the past. However, some scientific studies have had better results with Eucalyptus sargentii.
Overall, any drought-hardy species are suitable, such as tamarind, acacia, prosopis, pistachio, eucalyptus, date palm and carob. | 1 | Applied and Interdisciplinary Chemistry |
A magnetic field can also be used to focus charged particles. The Lorentz force acting on the electron is perpendicular to both the direction of motion and to the direction of the magnetic field (vxB). A homogeneous field deflects charged particles, but does not focus them. The simplest magnetic lens is a donut-shaped coil through which the beam passes, preferably along the axis of the coil. To generate the magnetic field, an electric current is passed through the coil. The magnetic field is strongest in the plane of the coil and gets weaker moving away from it. In the plane of the coil, the field gets stronger as we move away from the axis. Thus, a charged particle further from the axis experiences a stronger Lorentz force than a particle closer to the axis (assuming that they have the same velocity). This gives rise to the focusing action. Unlike the paths in an electrostatic lens, the paths in a magnetic lens contain a spiraling component, i.e. the charged particles spiral around the optical axis. As a consequence, the image formed by a magnetic lens is rotated relative to the object. This rotation is absent for an electrostatic lens.
The spatial extent of the magnetic field can be controlled by using an iron (or other magnetically soft material) magnetic circuit. This makes it possible to design and build more compact magnetic lenses with well defined optical properties. The vast majority of electron microscopes in use today use magnetic lenses due to their superior imaging properties and the absence of the high voltages that are required for electrostatic lenses. | 0 | Theoretical and Fundamental Chemistry |
The phenomenon of macromolecular crowding alters the properties of molecules in a solution when high concentrations of macromolecules such as proteins are present. Such conditions occur routinely in living cells; for instance, the cytosol of Escherichia coli contains about 300– of macromolecules. Crowding occurs since these high concentrations of macromolecules reduce the volume of solvent available for other molecules in the solution, which has the result of increasing their effective concentrations. Crowding can promote formation of a biomolecular condensate by colloidal phase separation.
This crowding effect can make molecules in cells behave in radically different ways than in test-tube assays. Consequently, measurements of the properties of enzymes or processes in metabolism that are made in the laboratory (in vitro) in dilute solutions may be different by many orders of magnitude from the true values seen in living cells (in vivo). The study of biochemical processes under realistically crowded conditions is very important, since these conditions are a ubiquitous property of all cells and crowding may be essential for the efficient operation of metabolism. Indeed, in vitro studies have shown that crowding greatly influences binding stability of proteins to DNA. | 0 | Theoretical and Fundamental Chemistry |
Cerium-doped lutetium aluminum perovskite (LuAP:Ce) single crystals were reported. The main property of those crystals is a large mass density of 8.4 g/cm, which gives short X- and gamma-ray absorption length. The scintillation light yield and the decay time with Cs radiation source are 11,400 photons/MeV and 17 ns, respectively. Those properties made LUAP:Ce scintillators attractive for commercials and they were used quite often in high energy physics experiments. Until eleven years later, one group in Japan proposed Ruddlesden-Popper solution-based hybrid organic-inorganic perovskite crystals as low-cost scintillators. However, the properties were not so impressive in comparison with LuAP:Ce. Until the next nine years, the solution-based hybrid organic-inorganic perovskite crystals became popular again through a report about their high light yields of more than 100,000 photons/MeV at cryogenic temperatures. Recent demonstration of perovskite nanocrystal scintillators for X-ray imaging screen was reported and it is triggering more research efforts for perovskite scintillators. Layered Ruddlesden-Popper perovskites have shown potential as fast novel scintillators with room temperature light yields up to 40,000 photons/MeV, fast decay times below 5 ns and negligible afterglow. In addition this class of materials have shown capability for wide-range particle detection, including alpha particles and thermal neutrons. | 0 | Theoretical and Fundamental Chemistry |
If an irrotational flow occupies a simply-connected fluid region then there exists a scalar field such that
The scalar field is called the velocity potential for the flow. (See Irrotational vector field.) | 1 | Applied and Interdisciplinary Chemistry |
Although some control exists at the transcriptional level, the regulation of cellular iron levels is ultimately controlled at the translational level by iron-responsive element-binding proteins IRP1 and especially IRP2. When iron levels are low, these proteins are able to bind to iron-responsive elements (IREs). IREs are stem loop structures in the untranslated regions (UTRs) of mRNA.
Both ferritin and ferroportin contain an IRE in their 5 UTRs, so that under iron deficiency their translation is repressed by IRP2, preventing the unnecessary synthesis of storage protein and the detrimental export of iron. In contrast, TFR1 and some DMT1 variants contain 3 UTR IREs, which bind IRP2 under iron deficiency, stabilizing the mRNA, which guarantees the synthesis of iron importers. | 1 | Applied and Interdisciplinary Chemistry |
The Caspian Sea region presently is a significant, but not major, supplier of crude oil to world markets, based upon estimates by BP Amoco and the U.S. Energy Information Administration, U.S. Department of Energy. The region output about 1.4–1.5 million barrels per day plus natural gas liquids in 2001, 1.9% of total world output. More than a dozen countries output more than this top figure. Caspian region production has been higher, but waned during and after the collapse of the Soviet Union. Kazakhstan accounts for 55% and Azerbaijan for about 20% of the states' oil output.
The world's first offshore wells and machine-drilled wells were made in Bibi-Heybat Bay, near Baku, Azerbaijan. In 1873, exploration and development of oil began in some of the largest fields known to exist in the world at that time on the Absheron Peninsula near the villages of Balakhanli, Sabunchi, Ramana, and Bibi Heybat. Total recoverable reserves were more than 500 million tons. By 1900, Baku had more than 3,000 oil wells, 2,000 of which were producing at industrial levels. By the end of the 19th century, Baku became known as the "black gold capital", and many skilled workers and specialists flocked to the city.
By the beginning of the 20th century, Baku was the center of the international oil industry. In 1920, when the Bolsheviks captured Azerbaijan, all private property, including oil wells and factories, was confiscated. Rapidly the republics oil industry came under the control of the Soviet Union. By 1941, Azerbaijan was producing a record 23.5 million tons of oil per year – its Baku region output was nearly 72 percent of the Soviet Unions oil.
In 1994, the "Contract of the Century" was signed, heralding extra-regional development of the Baku oil fields. The large Baku–Tbilisi–Ceyhan pipeline conveys Azeri oil to the Turkish Mediterranean port of Ceyhan and opened in 2006.
The oil field in the Russian section of the body of water was discovered in 2005. It is reportedly the largest found in 25 years. It was announced in October 2016 that Lukoil would start production from it. | 1 | Applied and Interdisciplinary Chemistry |
*[https://web.archive.org/web/20061110071206/http://www.neuro.wustl.edu/neuromuscular/pathol/lipofuscin.htm Histology at neuro.wustl.edu]
*[http://www.fightaging.org/archives/001624.php Destroying Lipofuscin and Destroying Cancer, FightAging.org]
*[https://web.archive.org/web/20081205135327/http://www.acceleratingfuture.com/people-blog/?p=2498 Unfocused Pulsed Lasers Selectively Destroy Lipofuscin, AcceleratingFuture.com]
* [https://en.longevitywiki.org/wiki/Lipofuscin Lipofuscin] | 1 | Applied and Interdisciplinary Chemistry |
In molecular biology, subcloning is a technique used to move a particular DNA sequence from a parent vector to a destination vector.
Subcloning is not to be confused with molecular cloning, a related technique. | 1 | Applied and Interdisciplinary Chemistry |
The HUGO Gene Nomenclature Committee is responsible for providing human gene naming guidelines and approving new, unique human gene names and symbols (short identifiers typically created by abbreviating). For some nonhuman species, model organism databases serve as central repositories of guidelines and help resources, including advice from curators and nomenclature committees. In addition to species-specific databases, approved gene names and symbols for many species can be located in the National Center for Biotechnology Information's "Entrez Gene" database. | 1 | Applied and Interdisciplinary Chemistry |
Fast endophilin-mediated endocytosis (FEME) is an endocytic pathway found in eukaryotic cells. It requires the activity of endophilins as well as dynamins, but does not require clathrin.
In Clathrin-dependent endocytic pathways, endosomes budding from the cell membrane into the cell will form in clathrin pits, and be coated by clathrin triskelions. In FEME however, endosomes form when coated by actin, and internalise endophilin A2. | 1 | Applied and Interdisciplinary Chemistry |
PCLake is designed to study the effects of eutrophication on shallow lakes and ponds. On one hand, the model is used by scientists to study the general behavior of these ecosystems. For example, PCLake is used to understand the phenomena of alternative stable states and hysteresis, and in that light, the relative importance of lake features such as water depth or fetch length. Also the potential effects of climate warming for shallow lakes have been studied. On the other hand, PCLake is applied by lake water resource managers that consider the turbid state as undesirable. They can use the model to define the critical loadings for their specific lakes and evaluate the effectiveness of restoration measures. For this purpose also a meta-model has been developed. The meta-model can be used by water managers to derive an estimate of the critical loading values for a certain lake based on only a few important parameters, without the need of running the full dynamical model. | 1 | Applied and Interdisciplinary Chemistry |
Coelenteramine is a metabolic product of the bioluminescent reactions in organisms that utilize coelenterazine. It was first isolated from Aequorea victoria along with coelenteramide after coelenterates were stimulated to emit light. | 1 | Applied and Interdisciplinary Chemistry |
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