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Colostrum There is currently much interest in the potential value of colostrum for the prevention and treatment of these conditions as it is derived from natural sources and can influence damaging factors through multiple pathways including nutritional support, immunological intervention (through its immunoglobulin and other anti-microbial factors) and growth/healing factor constituents. As pointed out by Kelly, inconsistency between results in some published studies may be due in part to variation in dose given and to the timing of the colostrum collection being tested (first milking versus pooled colostrum collected up to day 5 following calving). Some athletes have used colostrum in an attempt to improve their performance, decrease recovery time, and prevent sickness during peak performance levels. Supplementation with bovine colostrum, 20 grams per day (g/d), in combination with exercise training for 8 wk may increase bone-free lean body mass in active men and women. Low IGF-1 levels may be associated with dementia in the very elderly, although causation has not been established. People with eating disorders also have low levels of IGF-1 due to malnutrition, as do obese individuals. Supplementation with colostrum, which is rich in IGF-1, can be a useful part of a weight reduction program | https://en.wikipedia.org/wiki?curid=525722 |
Colostrum Although IGF-1 is not absorbed intact by the body, some studies suggest it stimulates the production of IGF-1 when taken as a supplement whereas others do not also has antioxidant components, such as lactoferrin and hemopexin, which binds free heme in the body. The Isle of Man had a local delicacy called "Groosniuys", a pudding made with colostrum. A sweet cheese like delicacy is made with colostrum in south Indian states of Andhra Pradesh, Telangana called 'Junnu'. This is made with the milk of buffalo as well as cow. the milk produced by Cow or a buffalo on the 2 day of giving birth is considered to be the best for making this pudding like delicacy. The colostrum has a very high demand in these states which has resulted in adulteration too. Hyperimmune colostrum is natural bovine colostrum collected from a population of cows immunized repeatedly with a specific pathogen. The colostrum is collected within 24 hours of the cow giving birth. Antibodies towards the specific pathogens or antigens that were used in the immunization are present in higher levels than in the population before treatment. Although some papers have been published stating that specific human pathogens were just as high as in hyperimmune colostrum, and natural colostrum nearly always had higher antibody titers than did the hyperimmune version | https://en.wikipedia.org/wiki?curid=525722 |
Colostrum Clinical trials have shown that if the immunization is by surface antigens of the bacteria, the Bovine Powder can be used to make tablets capable of binding to the bacteria so that they are excreted in stools. This prevents the successful colonization of the gut, which would otherwise lead to bacteria releasing enterotoxigenic materials. These small immune signaling peptides (PRPs) were independently discovered in colostrum and other sources, such as blood plasma, in the United States, Czechoslovakia and Poland. Hence they appear under various names in the literature, including Colostrinin, CLN, transfer factor and PRP. They function as signal transducing molecules that have the unique effect of modulating the immune system, turning it up when the body comes under attack from pathogens or other disease agents, and damping it when the danger is eliminated or neutralized. At first thought to actually transfer immunity from one immune system to another, it now appears that PRPs simply stimulate cell-mediated immunity. | https://en.wikipedia.org/wiki?curid=525722 |
Vladimir Kovalyonok Vladimir Vasiliyevich Kovalyonok (; ; born March 3, 1942 in Beloye, Minsk Oblast, Belorussian SSR) is a retired Soviet cosmonaut. He entered the Soviet space programme on July 5, 1967 and was commander of three missions. He retired from the cosmonaut team on June 23, 1984. From 1990 to 1992 he was a Director of the 30th Central Scientific Research Institute, Ministry of Defence (Russia). | https://en.wikipedia.org/wiki?curid=526903 |
Episodes (journal) Episodes is the quarterly journal of the International Union of Geological Sciences, published in Seoul, Korea. In circulation since 1978, Episodes is an international and interdisciplinary open access and free, both to submit and download, publication journal that covers all geoscience disciplines, including economic geology, environmental geology, geochemistry, geoethics, geoheritage, geophysics, hydrogeology, mineralogy, paleontology, petroleum geology, petrology, sedimentology, stratigraphy, structural geology, remote sensing, planetary geology, and social science (metric and diversity in publications and citations in Earth Sciences). Episodes includes authoritative articles that reflect global research advances, evolving trends in geoscience disciplines and concise reports on the results of international meetings, conferences, and symposia. It is a high visibility journal, and is indexed in Science Citation Index (SCI), Science Citation Index Expanded (SCIE; Web of Science), and Journal Citation Reports (JCR)/Science Edition, along with many other databases such as SCOPUS. Submitted manuscripts are peer-reviewed, and a first decision is provided to authors approximately within 30 days after submission. | https://en.wikipedia.org/wiki?curid=529843 |
T-type asteroid T-type asteroids are rare inner-belt asteroids of unknown composition with dark, featureless and moderately red spectra, and a moderate absorption feature shortwards of 0.85 μm. No direct meteorite analog has been found to date. Thought to be anhydrous, they are considered to be related to P-types or D-types, or possibly a highly altered C-type. Examples of T-type asteroids include 96 Aegle, 114 Kassandra, 233 Asterope, and 308 Polyxo. The infrared spectrum of the first three are similar to the mineral troilite, while 308 Pylyxo is modified with hydration features. | https://en.wikipedia.org/wiki?curid=532285 |
R-type asteroid R-type asteroids are moderately bright, relatively uncommon inner-belt asteroids that are spectrally intermediate between the V and A-type asteroids. The spectrum shows distinct olivine and pyroxene features at 1 and 2 micrometres, with a possibility of plagioclase. Shortwards of 0.7 μm the spectrum is very reddish. The IRAS mission has classified 4 Vesta, 246 Asporina, 349 Dembowska, 571 Dulcinea and 937 Bethgea as type R; however, the re-classification of Vesta, the V archetype, is debatable. Of these bodies, only 349 Dembowska is recognized as being type R when all wavelengths are taken into account. As of February 2019, at least 5 asteroids have been classified as R-type: | https://en.wikipedia.org/wiki?curid=532301 |
Q-type asteroid Q-type asteroids are relatively uncommon inner-belt asteroids with a strong, broad 1 micrometre olivine and pyroxene feature, and a spectral slope that indicates the presence of metal. There are absorption features shortwards and longwards of 0.7 μm, and the spectrum is generally intermediate between the V and S-type. Q-type asteroids are spectrally more similar to ordinary chondrite meteorites (types H, L, LL) than any other asteroid type. This has led scientists to speculate that they are abundant, but only about 20 of this type has been characterized. Examples of Q-type asteroids are: 1862 Apollo, 2102 Tantalus, 3753 Cruithne, 6489 Golevka, and 9969 Braille. | https://en.wikipedia.org/wiki?curid=532309 |
D-type asteroid D-type asteroids have a very low albedo and a featureless reddish spectrum. It has been suggested that they have a composition of organic-rich silicates, carbon and anhydrous silicates, possibly with water ice in their interiors. D-type asteroids are found in the outer asteroid belt and beyond; examples are 152 Atala, and 944 Hidalgo as well as the majority of Jupiter trojans. It has been suggested that the Tagish Lake meteorite was a fragment from a D-type asteroid, and that the Martian moon Phobos is closely related. The Nice model suggests that D-type asteroids may have originated in the Kuiper belt. 46 D-type asteroids are known, including 3552 Don Quixote, 944 Hidalgo, 624 Hektor, and 10199 Chariklo. A list of some of the largest D-type asteroids. | https://en.wikipedia.org/wiki?curid=532322 |
G-type asteroid G-type asteroids are a relatively uncommon type of carbonaceous asteroid that makes up approximately 5% of asteroids. The most notable asteroid in this class is 1 Ceres. Generally similar to the C-type objects, but contain a strong ultraviolet absorption feature below 0.5 μm. An absorption feature around 0.7 μm may also be present, which is indicative of phyllosilicate minerals such as clays or mica. In the SMASS classification the G-type corresponds to the Cgh and Cg types, depending on the presence or absence (respectively) of the absorption feature at 0.7 μm. The G-type, C-type and some rare types are sometimes collected together into a wider C-group of carbonaceous asteroids. | https://en.wikipedia.org/wiki?curid=532323 |
F-type asteroid F-type asteroids are a relatively uncommon type of carbonaceous asteroid, falling into the wider C-group. F-type asteroids have spectra generally similar to those of the B-type asteroids, but lack the "water" absorption feature around 3 μm indicative of hydrated minerals, and differ in the low wavelength part of the ultraviolet spectrum below 0.4 μm. The F-type and B-type asteroids are not distinguishable with the criteria used in the SMASS classification, so in that scheme are grouped together under the B-type. | https://en.wikipedia.org/wiki?curid=532325 |
Place theory (hearing) Place theory is a theory of hearing that states that our perception of sound depends on where each component frequency produces vibrations along the basilar membrane. By this theory, the pitch of a sound, such as a human voice or a musical tone, is determined by the places where the membrane vibrates, based on frequencies corresponding to the tonotopic organization of the primary auditory neurons. More generally, schemes that base attributes of auditory perception on the neural firing rate as a function of place are known as rate–place schemes. The main alternative to the place theory is the temporal theory, also known as timing theory. These theories are closely linked with the volley principle or volley theory, a mechanism by which groups of neurons can encode the timing of a sound waveform. In all cases, neural firing patterns in time determine the perception of pitch. The combination known as the place–volley theory uses both mechanisms in combination, primarily coding low pitches by temporal pattern and high pitches by rate–place patterns. It is now generally believed that there is good evidence for both mechanisms. The place theory is usually attributed to Hermann Helmholtz, though it was widely believed much earlier. Experiments to distinguish between place theory and rate theory are difficult to devise, because of the strong correlation: large vibrations with low rate are produced at the apical end of the basilar membrane while large vibrations with high rate are produced at the basal end | https://en.wikipedia.org/wiki?curid=533206 |
Place theory (hearing) The two can be controlled independently using cochlear implants: pulses with a range of rates can be applied via electrodes distributed along the membrane. Experiments using implant recipients showed that, at low stimulation rates, ratings of pitch on a pitch scale were proportional to the log of stimulation rate, but also decreased with distance from the round window. At higher rates, the effect of rate was weaker, but the effect of place was strong. | https://en.wikipedia.org/wiki?curid=533206 |
Sedna Planitia is a large lowland area of Venus, south of Ishtar Terra. It is thought to be lava-covered and similar to a lunar mare. Its name is derived from the Inuit sea goddess. | https://en.wikipedia.org/wiki?curid=538459 |
Emanuel Kayser Friedrich Heinrich (March 26, 1845November 29, 1927) was a German geologist and palaeontologist, born in Königsberg. He was educated at the universities of Halle, Heidelberg and Berlin, where in 1871 he qualified as a lecturer in geology. From 1873 he worked as a state geologist for the "Preußischen Geologischen Landesanstalt" (Prussian Geological Survey), and in 1881 became a professor at the Berlin Mining Academy. In 1885 he succeeded Wilhelm Dunker as professor of geology and paleontology at the University of Marburg. He is known for his work involving the stratigraphy, tectonics and paleontology of Paleozoic formations in Germany; especially the Harz and the Rhenish Massif. With Wilhelm Dames, he was co-editor of the journal "Paläontologischen Abhandlungen". Among his separate works are "Lehrbuch der Geologie" (2 vols.): ii. "Geologische Formationskunde" (1891; 2nd ed., 1902), and i. "Allgemeine Geologie" (1893); vol. ii. (the volume first issued) was translated and edited by Philip Lake, under the title "Textbook of Comparative Geology" (1893). Another work is "Beiträge zur Kenntniss der Fauna der Siegenschen Grauwacke" (1892). Kayser Bjerg, a mountain in Greenland, was named after him. | https://en.wikipedia.org/wiki?curid=538671 |
Cloud formation and climate change Nephology (; from the Greek word "nephos" for 'cloud') is the study of clouds and cloud formation. British meteorologist Luke Howard was a major researcher within this field, establishing a cloud classification system. While this branch of meteorology still exists today, the term nephology, or nephologist is rarely used. The term came into use at the end of the nineteenth century, and fell out of common use by the middle of the twentieth. Recently, interest in nephology (if not the name) has surged as many meteorologists have begun to focus on the relationship between clouds and global warming. Some nephologists believe that an increase in global temperature could decrease the thickness and brightness (ability to reflect light energy), which would further increase global temperature. Recently research has been going on at CERN's CLOUD facility to study the effects of the solar cycle and cosmic rays on cloud formation. | https://en.wikipedia.org/wiki?curid=538820 |
Pol Duwez (11 December 1907 – 31 December 1984) was a Belgian-born materials scientist. While working at Caltech in 1960, he first introduced metallic glasses made through rapid liquid cooling using a technique known as Splat quenching. | https://en.wikipedia.org/wiki?curid=541658 |
Visconte Maggiolo (1478 – after 1549), also spelled "Maiollo" and "Maiolo", was a Genoese cartographer. He was born in Genoa and maybe he was a fellow sailor of explorer Giovanni da Verrazzano. In 1511 he moved to Naples, where he produced three extant nautical atlases. Some historians say that he died of malaria in 1530; but archival documents show that he was still alive, in Genoa, at least in 1549, although he certainly was already dead in 1561. In 1527, he created a map depicting Verrazzano's travels. This map had a major error (so-called "Verrazzano Sea" with his "Verrazzano Isthmus", as Giovanni did not accurately describe the North American continent. This error kept on showing up in maps for over a century. A copy of this 1527 map was destroyed during World War II. There are numerous portolan charts, atlases and at least two other world maps made by Vesconte Maggiolo: one dated Genoa, 1531; another kept at a public library in Treviso (in Italian), is dated Genoa, 1549. | https://en.wikipedia.org/wiki?curid=542652 |
Protein purification is a series of processes intended to isolate one or a few proteins from a complex mixture, usually cells, tissues or whole organisms. is vital for the characterization of the function, structure and interactions of the protein of interest. The purification process may separate the protein and non-protein parts of the mixture, and finally separate the desired protein from all other proteins. Separation of one protein from all others is typically the most laborious aspect of protein purification. Separation steps usually exploit differences in protein size, physico-chemical properties, binding affinity and biological activity. The pure result may be termed protein isolate. is either "preparative" or "analytical". Preparative purifications aim to produce a relatively large quantity of purified proteins for subsequent use. Examples include the preparation of commercial products such as enzymes (e.g. lactase), nutritional proteins (e.g. soy protein isolate), and certain biopharmaceuticals (e.g. insulin). Several preparative purifications steps are often deployed to remove bi-products, such as host cell proteins, which poses as a potential threat to the patient's health. Analytical purification produces a relatively small amount of a protein for a variety of research or analytical purposes, including identification, quantification, and studies of the protein's structure, post-translational modifications and function. Pepsin and urease were the first proteins purified to the point that they could be crystallized | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification If the protein of interest is not secreted by the organism into the surrounding solution, the first step of each purification process is the disruption of the cells containing the protein. Depending on how fragile the protein is and how stable the cells are, one could, for instance, use one of the following methods: i) repeated freezing and thawing, ii) sonication, iii) homogenization by high pressure (French press), iv) homogenization by grinding (bead mill), and v) permeabilization by detergents (e.g. Triton X-100) and/or enzymes (e.g. lysozyme). Finally, the cell debris can be removed by centrifugation so that the proteins and other soluble compounds remain in the supernatant. Also proteases are released during cell lysis, which will start digesting the proteins in the solution. If the protein of interest is sensitive to proteolysis, it is recommended to proceed quickly, and to keep the extract cooled, to slow down the digestion. Alternatively, one or more protease inhibitors can be added to the lysis buffer immediately before cell disruption. Sometimes it is also necessary to add DNAse in order to reduce the viscosity of the cell lysate caused by a high DNA content. In bulk protein purification, a common first step to isolate proteins is precipitation with ammonium sulfate (NH)SO. This is performed by adding increasing amounts of ammonium sulfate and collecting the different fractions of precipitated protein. Subsequently, ammonium sulfate can be removed using dialysis | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification During the ammonium sulfate precipitation step, hydrophobic groups present on the proteins are exposed to the atmosphere, attracting other hydrophobic groups; the result is formation of an aggregate of hydrophobic components. In this case, the protein precipitate will typically be visible to the naked eye. One advantage of this method is that it can be performed inexpensively, even with very large volumes. The first proteins to be purified are water-soluble proteins. Purification of integral membrane proteins requires disruption of the cell membrane in order to isolate any one particular protein from others that are in the same membrane compartment. Sometimes a particular membrane fraction can be isolated first, such as isolating mitochondria from cells before purifying a protein located in a mitochondrial membrane. A detergent such as sodium dodecyl sulfate (SDS) can be used to dissolve cell membranes and keep membrane proteins in solution during purification; however, because SDS causes denaturation, milder detergents such as Triton X-100 or CHAPS can be used to retain the protein's native conformation during complete purification. Centrifugation is a process that uses centrifugal force to separate mixtures of particles of varying masses or densities suspended in a liquid | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification When a vessel (typically a tube or bottle) containing a mixture of proteins or other particulate matter, such as bacterial cells, is rotated at high speeds, the inertia of each particle yields a force in the direction of the particles velocity that is proportional to its mass. The tendency of a given particle to move through the liquid because of this force is offset by the resistance the liquid exerts on the particle. The net effect of "spinning" the sample in a centrifuge is that massive, small, and dense particles move outward faster than less massive particles or particles with more "drag" in the liquid. When suspensions of particles are "spun" in a centrifuge, a "pellet" may form at the bottom of the vessel that is enriched for the most massive particles with low drag in the liquid. Non-compacted particles remain mostly in the liquid called "supernatant" and can be removed from the vessel thereby separating the supernatant from the pellet. The rate of centrifugation is determined by the angular acceleration applied to the sample, typically measured in comparison to the "g". If samples are centrifuged long enough, the particles in the vessel will reach equilibrium wherein the particles accumulate specifically at a point in the vessel where their buoyant density is balanced with centrifugal force. Such an "equilibrium" centrifugation can allow extensive purification of a given particle | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification Sucrose gradient centrifugation — a linear concentration gradient of sugar (typically sucrose, glycerol, or a silica based density gradient media, like Percoll) is generated in a tube such that the highest concentration is on the bottom and lowest on top. Percoll is a trademark owned by GE Healthcare companies. A protein sample is then layered on top of the gradient and spun at high speeds in an ultracentrifuge. This causes heavy macromolecules to migrate towards the bottom of the tube faster than lighter material. During centrifugation in the absence of sucrose, as particles move farther and farther from the center of rotation, they experience more and more centrifugal force (the further they move, the faster they move). The problem with this is that the useful separation range of within the vessel is restricted to a small observable window. Spinning a sample twice as long doesn't mean the particle of interest will go twice as far, in fact, it will go significantly further. However, when the proteins are moving through a sucrose gradient, they encounter liquid of increasing density and viscosity. A properly designed sucrose gradient will counteract the increasing centrifugal force so the particles move in close proportion to the time they have been in the centrifugal field. Samples separated by these gradients are referred to as "rate zonal" centrifugations. After separating the protein/particles, the gradient is then fractionated and collected | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification Choice of a starting material is key to the design of a purification process. In a plant or animal, a particular protein usually isn't distributed homogeneously throughout the body; different organs or tissues have higher or lower concentrations of the protein. Use of only the tissues or organs with the highest concentration decreases the volumes needed to produce a given amount of purified protein. If the protein is present in low abundance, or if it has a high value, scientists may use recombinant DNA technology to develop cells that will produce large quantities of the desired protein (this is known as an expression system). Recombinant expression allows the protein to be tagged, e.g. by a His-tag or Strep-tag to facilitate purification, reducing the number of purification steps required. An analytical purification generally utilizes three properties to separate proteins. First, proteins may be purified according to their isoelectric points by running them through a pH graded gel or an ion exchange column. Second, proteins can be separated according to their size or molecular weight via size exclusion chromatography or by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) analysis. Proteins are often purified by using 2D-PAGE and are then analysed by peptide mass fingerprinting to establish the protein identity. This is very useful for scientific purposes and the detection limits for protein are nowadays very low and nanogram amounts of protein are sufficient for their analysis | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification Thirdly, proteins may be separated by polarity/hydrophobicity via high performance liquid chromatography or reversed-phase chromatography. Usually a protein purification protocol contains one or more chromatographic steps. The basic procedure in chromatography is to flow the solution containing the protein through a column packed with various materials. Different proteins interact differently with the column material, and can thus be separated by the time required to pass the column, or the conditions required to elute the protein from the column. Usually proteins are detected as they are coming off the column by their absorbance at 280 nm. Many different chromatographic methods exist: Chromatography can be used to separate protein in solution or denaturing conditions by using porous gels. This technique is known as size exclusion chromatography. The principle is that smaller molecules have to traverse a larger volume in a porous matrix. Consequentially, proteins of a certain range in size will require a variable volume of eluent (solvent) before being collected at the other end of the column of gel. In the context of protein purification, the eluent is usually pooled in different test tubes. All test tubes containing no measurable trace of the protein to purify are discarded. The remaining solution is thus made of the protein to purify and any other similarly-sized proteins | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification HIC media is amphiphilic, with both hydrophobic and hydrophilic regions, allowing for separation of proteins based on their surface hydrophobicity. Target proteins and their product aggregate species tend to have different hydrophobic properties and removing them via HIC further purifies the protein of interest. Additionally, the environment used typically employs less harsh denaturing conditions than other chromatography techniques, thus helping to preserve the protein of interest in its native and functional state. In pure water, the interactions between the resin and the hydrophobic regions of protein would be very weak, but this interaction is enhanced by applying a protein sample to HIC resin in high ionic strength buffer. The ionic strength of the buffer is then reduced to elute proteins in order of decreasing hydrophobicity. Ion exchange chromatography separates compounds according to the nature and degree of their ionic charge. The column to be used is selected according to its type and strength of charge. Anion exchange resins have a positive charge and are used to retain and separate negatively charged compounds (anions), while cation exchange resins have a negative charge and are used to separate positively charged molecules (cations). Before the separation begins a buffer is pumped through the column to equilibrate the opposing charged ions. Upon injection of the sample, solute molecules will exchange with the buffer ions as each competes for the binding sites on the resin | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification The length of retention for each solute depends upon the strength of its charge. The most weakly charged compounds will elute first, followed by those with successively stronger charges. Because of the nature of the separating mechanism, pH, buffer type, buffer concentration, and temperature all play important roles in controlling the separation. Ion exchange chromatography is a very powerful tool for use in protein purification and is frequently used in both analytical and preparative separations. Free-flow electrophoresis (FFE) is a carrier-free electrophoresis technique that allows preparative protein separation in a laminar buffer stream by using an orthogonal electric field. By making use of a pH-gradient, that can for example be induced by ampholytes, this technique allows to separate protein isoforms up to a resolution of < 0.02 delta-pI. Affinity Chromatography is a separation technique based upon molecular conformation, which frequently utilizes application specific resins. These resins have ligands attached to their surfaces which are specific for the compounds to be separated. Most frequently, these ligands function in a fashion similar to that of antibody-antigen interactions. This "lock and key" fit between the ligand and its target compound makes it highly specific, frequently generating a single peak, while all else in the sample is unretained. Many membrane proteins are glycoproteins and can be purified by lectin affinity chromatography | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification Detergent-solubilized proteins can be allowed to bind to a chromatography resin that has been modified to have a covalently attached lectin. Proteins that do not bind to the lectin are washed away and then specifically bound glycoproteins can be eluted by adding a high concentration of a sugar that competes with the bound glycoproteins at the lectin binding site. Some lectins have high affinity binding to oligosaccharides of glycoproteins that is hard to compete with sugars, and bound glycoproteins need to be released by denaturing the lectin. Immunoaffinity chromatography uses the specific binding of an antibody-antigen to selectively purify the target protein. The procedure involves immobilizing a protein to a solid substrate (e.g. a porous bead or a membrane), which then selectively binds the target, while everything else flows through. The target protein can be eluted by changing the pH or the salinity. The immobilized ligand can be an antibody (such as Immunoglobulin G) or it can be a protein (such as Protein A). Because this method does not involve engineering in a tag, it can be used for proteins from natural sources. Another way to tag proteins is to engineer an antigen peptide tag onto the protein, and then purify the protein on a column or by incubating with a loose resin that is coated with an immobilized antibody. This particular procedure is known as immunoprecipitation | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification Immunoprecipitation is quite capable of generating an extremely specific interaction which usually results in binding only the desired protein. The purified tagged proteins can then easily be separated from the other proteins in solution and later eluted back into clean solution. When the tags are not needed anymore, they can be cleaved off by a protease. This often involves engineering a protease cleavage site between the tag and the protein. High performance liquid chromatography or high pressure liquid chromatography is a form of chromatography applying high pressure to drive the solutes through the column faster. This means that the diffusion is limited and the resolution is improved. The most common form is "reversed phase" HPLC, where the column material is hydrophobic. The proteins are eluted by a gradient of increasing amounts of an organic solvent, such as acetonitrile. The proteins elute according to their hydrophobicity. After purification by HPLC the protein is in a solution that only contains volatile compounds, and can easily be lyophilized. HPLC purification frequently results in denaturation of the purified proteins and is thus not applicable to proteins that do not spontaneously refold. At the end of a protein purification, the protein often has to be concentrated. Different methods exist. If the solution doesn't contain any other soluble component than the protein in question the protein can be lyophilized (dried). This is commonly done after an HPLC run | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification This simply removes all volatile components, leaving the proteins behind. Ultrafiltration concentrates a protein solution using selective permeable membranes. The function of the membrane is to let the water and small molecules pass through while retaining the protein. The solution is forced against the membrane by mechanical pump, gas pressure, or centrifugation. The most general method to monitor the purification process is by running a SDS-PAGE of the different steps. This method only gives a rough measure of the amounts of different proteins in the mixture, and it is not able to distinguish between proteins with similar apparent molecular weight. If the protein has a distinguishing spectroscopic feature or an enzymatic activity, this property can be used to detect and quantify the specific protein, and thus to select the fractions of the separation, that contains the protein. If antibodies against the protein are available then western blotting and ELISA can specifically detect and quantify the amount of desired protein. Some proteins function as receptors and can be detected during purification steps by a ligand binding assay, often using a radioactive ligand. In order to evaluate the process of multistep purification, the amount of the specific protein has to be compared to the amount of total protein. The latter can be determined by the Bradford total protein assay or by absorbance of light at 280 nm, however some reagents used during the purification process may interfere with the quantification | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification For example, imidazole (commonly used for purification of polyhistidine-tagged recombinant proteins) is an amino acid analogue and at low concentrations will interfere with the bicinchoninic acid (BCA) assay for total protein quantification. Impurities in low-grade imidazole will also absorb at 280 nm, resulting in an inaccurate reading of protein concentration from UV absorbance. Another method to be considered is Surface Plasmon Resonance (SPR). SPR can detect binding of label free molecules on the surface of a chip. If the desired protein is an antibody, binding can be translated directly to the activity of the protein. One can express the active concentration of the protein as the percent of the total protein. SPR can be a powerful method for quickly determining protein activity and overall yield. It is a powerful technology that requires an instrument to perform. Gel electrophoresis is a common laboratory technique that can be used both as preparative and analytical method. The principle of electrophoresis relies on the movement of a charged ion in an electric field. In practice, the proteins are denatured in a solution containing a detergent (SDS). In these conditions, the proteins are unfolded and coated with negatively charged detergent molecules. The proteins in SDS-PAGE are separated on the sole basis of their size. In analytical methods, the protein migrate as bands based on size. Each band can be detected using stains such as Coomassie blue dye or silver stain | https://en.wikipedia.org/wiki?curid=542744 |
Protein purification Preparative methods to purify large amounts of protein, require the extraction of the protein from the electrophoretic gel. This extraction may involve excision of the gel containing a band, or eluting the band directly off the gel as it runs off the end of the gel. In the context of a purification strategy, denaturing condition electrophoresis provides an improved resolution over size exclusion chromatography, but does not scale to large quantity of proteins in a sample as well as the late chromatography columns. A non-denaturing electrophoretic procedure for isolating bioactive metalloproteins in complex protein mixtures is preparative native PAGE. The intactness or the structural integrity of the isolated protein has to be confirmed by an independent method. | https://en.wikipedia.org/wiki?curid=542744 |
Eadie–Hofstee diagram In biochemistry, an (also Woolf–Eadie–Augustinsson–Hofstee or Eadie–Augustinsson plot) is a graphical representation of enzyme kinetics. In the diagram the reaction rate is plotted as a function of the ratio between rate and substrate concentration: where "v" represents reaction rate, "K" is the Michaelis–Menten constant, ["S"] is the substrate concentration, and "V" is the maximum reaction rate. It can be derived from the Michaelis–Menten equation as follows: invert and multiply with formula_3: Rearrange: Isolate v: A plot of v against "v"/[S] will hence yield "V" as the y-intercept, "V"/K as the x-intercept, and "K" as the negative slope. Like other techniques that linearize the Michaelis–Menten equation, the Eadie–Hofstee plot was used historically for rapid identification of important kinetic terms like "K" and "V", but has been superseded by nonlinear regression methods that are significantly more accurate and no longer computationally inaccessible. It is also more robust against error-prone data than the Lineweaver–Burk plot, particularly because it gives equal weight to data points in any range of substrate concentration or reaction rate. (The Lineweaver–Burk plot unevenly weights such points.) Both plots remain useful as a means to present data graphically. One drawback from the Eadie–Hofstee approach is that neither ordinate nor abscissa represent independent variables: both are dependent on reaction rate. Thus any experimental error will be present in both axes | https://en.wikipedia.org/wiki?curid=544919 |
Eadie–Hofstee diagram Also, experimental error or uncertainty will propagate unevenly and become larger over the abscissa thereby giving more weight to smaller values of "v"/[S]. Therefore, the typical measure of goodness of fit for linear regression, the correlation coefficient "R", is not applicable. | https://en.wikipedia.org/wiki?curid=544919 |
Hoffmann-La Roche F. AG is a Swiss multinational healthcare company that operates worldwide under two divisions: Pharmaceuticals and Diagnostics. Its holding company, Roche Holding AG, has bearer shares listed on the SIX Swiss Exchange. The company headquarters are located in Basel. The company controls the American biotechnology company Genentech, which is a wholly owned affiliate, and the Japanese biotechnology company Chugai Pharmaceuticals, as well as the United States-based Ventana. Roche's revenues during fiscal year 2018 were 56.85 billion Swiss francs, or approximately US$57 billion. Roche is the second-largest pharmaceutical company worldwide. Descendants of the founding Hoffmann and Oeri families own slightly over half of the bearer shares with voting rights (a pool of family shareholders 45%, and Maja Oeri a further 5% apart), with Swiss pharma firm Novartis owning a further third of its shares. Roche is one of the few companies increasing their dividend every year, for 2018 as the 32nd consecutive year. F. is a full member of the European Federation of Pharmaceutical Industries and Associations (EFPIA). Founded in 1896 by Fritz Hoffmann-La Roche, the company was early on known for producing various vitamin preparations and derivatives. In 1934, it became the first company to mass-produce synthetic vitamin C, under the brand name Redoxon. In 1957 it introduced the class of tranquilizers known as benzodiazepines (with Valium and Rohypnol being the best known members) | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche It manufactures and sells several cancer drugs and is a leader in this field. In 1956, the first antidepressant, iproniazid, was accidentally created during an experiment while synthesizing isoniazid. Originally, it had been intended to create a more efficient drug at combatting Tuberculosis. Iproniazid, however, revealed to have its own benefits; some people felt it made them feel happier. It was withdrawn from the market in the early 1960s due to toxic side-effects. In 1976, an accident at a chemical factory in Seveso, Italy, owned by a subsidiary of Roche, caused a large dioxin contamination; see Seveso disaster. In 1982, the United States arm of the company acquired Biomedical Reference Laboratories for US$163.5 million. That company dated from the late 1960s, and was located in Burlington, North Carolina. That year then merged it with all of its laboratories, and incorporated the merged company as Roche Biomedical Laboratories, Inc. in Burlington. By the early 1990s, Roche Biomedical became one of the largest clinical laboratory networks in the United States, with 20 major laboratories and US$600 million in sales. Roche has also produced various HIV tests and antiretroviral drugs. It bought the patents for the polymerase chain reaction (PCR) technique in 1992. In 1995 the era of highly active anti-retroviral therapy (HAART) was initiated by the United States FDA's approval of Hoffman LaRoche's HIV protease inhibitor saquinavir | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche Within 2 years of its approval (and that of ritonavir 4 months later) annual deaths from AIDS in the United States fell from over 50,000 to approximately 18,000 On 28 April 1995 sold Roche Biomedical Laboratories, Inc. to National Health Laboratories Holdings Inc. (which then changed its name to Laboratory Corporation of America Holdings). Roche acquired Syntex in 1994 and Chugai Pharmaceuticals in 2002. Oseltamivir is considered to be the primary antiviral drug used to combat avian influenza, commonly known as the bird flu. Roche is the only drug company authorized to manufacture the drug, which was discovered by Gilead Sciences. Roche purchased the rights to the drug in 1996 and in 2005 settled a royalty dispute, agreeing to pay Gilead tiered royalties of 14–22% of annual net sales without adjusting the payments for manufacturing costs, as had been allowed in the original licensing agreement. On 20 October 2005 decided to license other companies to manufacture Oseltamivir. Also in 2005 Roche acquired the Swiss company GlycArt Biotechnology in order to acquire technology to afucosylate antibodies; one of its products in development was obinutuzumab, which gained FDA approval in November 2013 for the treatment of chronic lymphocytic leukemia. On 22 January 2008 Roche acquired Ventana Medical Systems for $3.4 billion. On 2 January 2009, Roche acquired Memory Pharmaceuticals Corp. On 26 March 2009, Roche acquired Genentech for $46.8 billion | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche On 12 March 2009 Roche agreed to fully acquire Genentech, which it had held a majority stake since 1990, after eight months of negotiations. As a result of the Genentech acquisition, Roche moved its Palo Alto based research facilities to their campus that straddles the border between Clifton, New Jersey and Nutley, New Jersey while Roche's United States headquarters, located on the site since 1929, was moved to Genentech's facility in South San Francisco. Genentech became a wholly owned subsidiary group of Roche on 25 March 2009. Roche acquired Medingo Ltd. in April 2010 for $160 million and BioImagene, Inc. in August for $100 million. In 2011, the company received the International Society for Pharmaceutical Engineering Facility of the Year Award for Process Innovation for Roche’s "MyDose" Clinical Supply project. In March 2011, Roche acquired PVT Probenverteiltechnik GmbH for up to €85 million. In July 2010, Roche acquired mtm laboratories AG for up to 190 million EUR. On October, Roche acquired Anadys Pharmaceuticals, Inc. for $230 million. In December, Roche announced it would acquire Munich-based Verum Diagnostica GmbH, gaining entry to the fastest-growing field in the coagulation diagnostics market. On 26 June 2012, Roche announced the closure of the Nutley/Clifton campus, which was completed in 2013. The property is in the process of remediation. In July 2013, Roche Diagnostics acquired blood diagnostics company Constitution Medical Inc. for $220 million | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche Later, in September, Genentech announced it would acquire Arrayit Corporation. On 7 April 2014, Roche announced its intention to acquire IQuum for up to $450 million, as well as the rights to an experimental drug (ORY-1001) from Spanish company Oryzon Genomics for $21 million and up to $500 million in milestone payments. On 2 June, Roche announced its intention to acquire Genia Technologies Inc. for up to $350 million. In August 2014, the company agreed to purchase Californian-based pharmaceutical firm InterMune for $8.3 billion, at $74 a share this represents a 38% premium over the final share closing price, as well as Santaris Pharma A/S for $450 million. In December 2014, the company acquired next-generation sequencing processing company Bina Technologies for an undisclosed sum and Dutalys GmbH a developer of next-generation anti-bodies. On 16 January 2015, the company announced that they would acquire Trophos for €470 million ($543 million) in order to increase the company's neuromuscular disease presence. The deal will centre on the Phase II and III spinal muscular atrophy drug olesoxime (TRO19622). In April 2015, Roche acquired CAPP Medical, and its chief development of technology for cancer screening and monitoring via the detection of circulating tumor DNA. In August, the company announced its intention to acquire GeneWEAVE , Inc. for up to $425 million in order to strengthen its microbial diagnostics business. Days later the company acquired Kapa Biosystems, Inc | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche for $445M, focussing on next generation sequencing and polymerase chain reaction applications. In October 2015, the company acquired Adheron Therapeutics for $105 million (plus up to $475 million in milestone payments). In January 2016, the company announced it would acquire Tensha Therapeutics for $115 million upfront, with $420 million in contingent payments. In January 2017, the company acquired ForSight VISION4. In June, the company acquired the diabetes management platform, mySugr GmbH for an undisclosed price. In November Roche acquired Viewics, Inc. In late December the company announced it would acquire Ignyta Inc, expanding its global oncology business. In February 2018, Roche announced it would acquire Flatiron Health, a business specialising in US cancer data analytics, for $1.9 billion. In June of the same year the company announced it would acquire the outstanding shares of Foundation Medicine for $2.4 billion ($137 per share). Later in September Roche announced its intention to acquire Tusk Therapeutics for up to €655 million ($759 million) expanding Roche's oncology pipeline. Tusk announced that the anti-CD38 antibody it is developing will be spun off to form a new company, Black Belt Therapeutics. In late November, the company announced that Genentech would acquire Jecure Therapeutics, gaining access to Jecure's portfolio of NLRP3 inhibitors developed to fight inflammatory diseases like non-alcoholic steatohepatitis and liver fibrosis | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche In February 2019, the business announced it would acquire gene therapy company, Spark Therapeutics, for ($114.50 per share) adding Spark's gene therapy portfolio to its previous acquired assets. Spark has an already approved treatment for Leber’s congenital amaurosis, Luxturna - priced at per patient per year. The offer to acquire Spark Therapeutics was extended to May 2019 after Roche was unable to garner majority support from Spark shareholders. A second gene therapy-related action came in December with the acquisition of non-United States rights to an investigational duchenne muscular dystrophy gene therapy developed by Sarepta Therapeutics. In November Roche acquired Promedior and its lead treatment - PRM-151 - for the treatment of idiopathic pulmonary fibrosis, for $390 million upfront and another $1 billion in milestone payments. In March 2020, the Roche Diagnostics division reached a significant milestone with the FDA-approval of its high-volume Sars-CoV-2 diagnostic test, capable of analyzing 1,400-8,800 samples within 24h on the proprietary cobas 6800/8800 molecular testing system. is strong in the field pharmaceuticals for cancer treatment, against virus diseases and for treatment of metabolic diseases. The company is the world's largest spender in pharmaceutical R&D | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche Drugs produced by Roche include: Diabetes management products produced by Roche under the Accu-Chek brand include Accu-Chek Mobile, Accu-Chek Aviva, Accu-Chek Compact Plus, Accu-Chek Aviva Expert, Accu-Chek Active, Accu-Chek Advantage, Accu-Chek Performa, Accu-Chek Aviva Nano, Accu-Chek Performa Nano blood glucose monitors. Accu-Chek Spirit and Accu-Chek Combo insulin pumps. Accu-Chek 360 and SmartPix diabetes management software. Other products include: Stanley Adams, Roche's World Product Manager in Basel, contacted the European Economic Community in 1973 with evidence that Roche had been breaking antitrust laws, engaging in price fixing and market sharing for vitamins with its competitors. Roche was fined accordingly, but a bungle on the part of the EEC allowed the company to discover that it was Adams who had blown the whistle. He was arrested for unauthorised disclosure — an offence under Swiss law — and imprisoned. His wife, having learnt that he might face decades in jail, committed suicide. In 1999 the firm pleaded guilty to participation in a worldwide conspiracy to raise and fix prices for vitamins sold in the US and globally. paid $500 million in criminal fines to the United States. In addition to internal research and development activities F. is also involved in publicly funded collaborative research projects, with other industrial and academic partners. One example in the area of non-clinical safety assessment is the InnoMed PredTox | https://en.wikipedia.org/wiki?curid=548739 |
Hoffmann-La Roche The company is expanding its activities in joint research projects within the framework of the Innovative Medicines Initiative of EFPIA and the European Commission. | https://en.wikipedia.org/wiki?curid=548739 |
Bioship A bioship is a type of spacecraft or starship described in science fiction. Bioships differ from other types of spacecraft in that they are composed, either predominantly or totally, of biological components, rather than being constructed from manufactured materials. Because of this, they nearly always have a distinctively organic look. Bioships are usually quite powerful, and can often regenerate or heal damaged parts. Some bioships are intelligent or sentient, and some are considered to be lifeforms. Like most organic beings, many bioships contain large amounts of "scaffolding" materials to keep their shape, such as the xylem in trees or bone and chitin in animals. In the science fiction short story "Specialist" by Robert Sheckley, published in 1953 in "Galaxy" magazine, it is revealed that many galactic races are actually capable of symbiotic cooperation to become bioships, with each race forming a different part. Earth, apparently, is one of the planets inhabited by creatures that are supposed to function as FTL (faster than light) drives (Pushers), and, it is stated that all the conflicts and discontent of humanity are due to the fact that, while they have matured, they have nowhere to apply their true purpose. This story is perhaps the first mention of a bioship in science fiction. Volume 322 of the German Perry Rhodan magazine series, first published in November 1967, marks another very early appearance of the bioship concept in science fiction | https://en.wikipedia.org/wiki?curid=551450 |
Bioship The Dolans are powerful bioengineered combat spaceships that are grown from the same synthetic genetic material as their extraterrestrial commanders. Different types of bioships are a recurrent feature in later stages of the Perry Rhodan universe. "The Night's Dawn Trilogy": the Edenist Voidhawk and Mercenary Blackhawk are both advanced bioships (the latter being a genetic tailoring for combat of the former). Both types employ mental bonding to the captain. In the case of Voidhawks this is done by both the craft and captain gestating together and maintaining mental contact during their formative years. Blackhawks however are purchased as eggs and are bonded to the buyer who will become captain when the Blackhawk matures. In the first novel of Julian May's Pliocene series, "The Many-Colored Land" (1982), the backstory of two races of alien refugees living in the Earth's Pliocene epoch describes their hard landing in a bioship. The bioship was emotionally bonded to one of the aliens (the "shipwife") and sacrificed its own life to safely deliver its passengers to the planet surface. In the popular science fiction franchise Star Trek several bioships appear. On Babylon 5 , many of the First Ones used organic ships, like the Vorlon and Shadows races | https://en.wikipedia.org/wiki?curid=551450 |
Bioship Use of organic technology by these races signified their significant advancement over the younger races since their ships are very resilient, generate their own power, very maneuverable, have devastatingly powerful weapons (including variants that are capable of destroying planets), regenerate, and have a measure of intelligence. The episode features a bioship as the main part of the plot. Species 8472 also has an enormous fleet of bioships which are able to go toe to toe with, arguably the Federation's most malignant enemy, The Borg. The Zerg alien race in the video game "StarCraft" traverse space via sentient, organic vessels called "Leviathan". | https://en.wikipedia.org/wiki?curid=551450 |
F-center An F-center, Farbe center or color center (from the original German "Farbzentrum", where "Farbe" means "color" and "zentrum" means center) is a type of crystallographic defect in which an anionic vacancy in a crystal lattice is occupied by one or more unpaired electrons. Electrons in such a vacancy tend to absorb light in the visible spectrum such that a material that is usually transparent becomes colored. This is used to identify many compounds, especially zinc oxide (yellow). Color centers can occur naturally in compounds (particularly metallic oxides) because when heated to high temperature the ions become excited and are displaced from their normal crystallographic positions, leaving behind some electrons in the vacated spaces. This effect is also exhibited by ionic compounds containing metal-excess defects. F-centers are often paramagnetic and can be studied by electron paramagnetic resonance techniques. The greater the number of F-centers, the more intense the color of the compound. One way of producing F-centers in a crystal artificially is to heat it in an atmosphere of the metal of which it is constituted, e.g., heating NaCl in a metallic Na atmosphere. Na → Na + e Na is incorporated into the NaCl crystal after giving up an electron. A Cl vacancy is generated to balance the excess Na. The effective positive charge of the Cl vacancy traps the electron released by the Na atom | https://en.wikipedia.org/wiki?curid=552965 |
F-center This trapping of the electrons by anion vacancies results in the formation of F-centers; that is, the electrons released in this process diffuse to the vacant sites where negatively charged ions (i.e., anions) normally reside. Ionizing radiation can also produce F-centers. An H-center (a halogen interstitial) is in a sense the opposite to an F-center, so that when the two come into contact in a crystal they combine and cancel out both defects. This process can be photoinduced, e.g., using a laser. The formation of F-centers is the reason that some crystals like lithium chloride, potassium chloride, and zinc oxide become pink, lilac and yellow, respectively, when heated. | https://en.wikipedia.org/wiki?curid=552965 |
Immunofluorescence is a technique used for light microscopy with a fluorescence microscope and is used primarily on microbiological samples. This technique uses the specificity of antibodies to their antigen to target fluorescent dyes to specific biomolecule targets within a cell, and therefore allows visualization of the distribution of the target molecule through the sample. The specific region an antibody recognizes on an antigen is called an epitope. There have been efforts in epitope mapping since many antibodies can bind the same epitope and levels of binding between antibodies that recognize the same epitope can vary. Additionally, the binding of the fluorophore to the antibody itself cannot interfere with the immunological specificity of the antibody or the binding capacity of its antigen. is a widely used example of immunostaining (using antibodies to stain proteins) and is a specific example of immunohistochemistry (the use of the antibody-antigen relationship in tissues). This technique primarily makes use of fluorophores to visualise the location of the antibodies. can be used on tissue sections, cultured cell lines, or individual cells, and may be used to analyze the distribution of proteins, glycans, and small biological and non-biological molecules. This technique can even be used to visualize structures such as intermediate-sized filaments. If the topology of a cell membrane has yet to be determined, epitope insertion into proteins can be used in conjunction with immunofluorescence to determine structures | https://en.wikipedia.org/wiki?curid=553628 |
Immunofluorescence can also be used as a "semi-quantitative" method to gain insight into the levels and localization patterns of DNA methylation since it is a more time-consuming method than true quantitative methods and there is some subjectivity in the analysis of the levels of methylation. can be used in combination with other, non-antibody methods of fluorescent staining, for example, use of DAPI to label DNA. Several microscope designs can be used for analysis of immunofluorescence samples; the simplest is the epifluorescence microscope, and the confocal microscope is also widely used. Various super-resolution microscope designs that are capable of much higher resolution can also be used. To make fluorochrome-labeled antibodies, a fluorochrome must be conjugated ("tagged") to the antibody. Likewise, an antigen can also be conjugated to the antibody with a fluorescent probe in a technique called fluorescent antigen technique. Staining procedures can apply to both fixed antigen in the cytoplasm or to cell surface antigens on living cells, called "membrane immunofluorescence". It is also possible to label the complement of the antibody-antigen complex with a fluorescent probe. In addition to the element to which fluorescence probes are attached, there are two general classes of immunofluorescence techniques: primary and secondary. The following descriptions will focus primarily on these classes in terms of conjugated antibodies | https://en.wikipedia.org/wiki?curid=553628 |
Immunofluorescence There are two classes of immunofluorescence techniques, primary (or direct) and secondary (or indirect). Primary (direct) immunofluorescence uses a single, primary antibody, chemically linked to a fluorophore. The primary antibody recognizes the target molecule (antigen) and binds to a specific region called the epitope. This is accomplished by a process which manipulates the immune response of organism with adaptive immunity. The attached fluorophore can be detected via fluorescent microscopy, which, depending on the messenger used, will emit a specific wavelength of light once excited. Direct immunofluorescence, although somewhat less common, has notable advantages over the secondary (indirect) procedure. The direct attachment of the messenger to the antibody reduces the number of steps in the procedure, saving time and reducing non-specific background signal. This also limits the possibility of antibody cross-reactivity and possible mistakes throughout the process. </ref> However, some disadvantages do exist in this method. Since the number of fluorescent molecules that can be bound to the primary antibody is limited, direct immunofluorescence is substantially less sensitive than indirect immunofluorescence and may result in false negatives. Direct immunofluorescence also requires the use of much more primary antibody, which is extremely expensive, sometimes running up to $400.00/mL | https://en.wikipedia.org/wiki?curid=553628 |
Immunofluorescence Secondary (indirect) immunofluorescence uses two antibodies; the unlabeled first (primary) antibody specifically binds the target molecule, and the secondary antibody, which carries the fluorophore, recognizes the primary antibody and binds to it. Multiple secondary antibodies can bind a single primary antibody. This provides signal amplification by increasing the number of fluorophore molecules per antigen. This protocol is more complex and time-consuming than the primary (or direct) protocol above, but allows more flexibility because a variety of different secondary antibodies and detection techniques can be used for a given primary antibody. This protocol is possible because an antibody consists of two parts, a variable region (which recognizes the antigen) and constant region (which makes up the structure of the antibody molecule). It is important to realize that this division is artificial and in reality the antibody molecule is four polypeptide chains: two heavy chains and two light chains. A researcher can generate several primary antibodies that recognize various antigens (have different variable regions), but all share the same constant region. All these antibodies may therefore be recognized by a single secondary antibody. This saves the cost of modifying the primary antibodies to directly carry a fluorophore. Different primary antibodies with different constant regions are typically generated by raising the antibody in different species | https://en.wikipedia.org/wiki?curid=553628 |
Immunofluorescence For example, a researcher might create primary antibodies in a goat that recognize several antigens, and then employ dye-coupled rabbit secondary antibodies that recognize the goat antibody constant region ("rabbit anti-goat" antibodies). The researcher may then create a second set of primary antibodies in a mouse that could be recognized by a separate "donkey anti-mouse" secondary antibody. This allows re-use of the difficult-to-make dye-coupled antibodies in multiple experiments. As with most fluorescence techniques, a significant problem with immunofluorescence is photobleaching. Loss of activity caused by photobleaching can be controlled by reducing or limiting the intensity or time-span of light exposure, by increasing the concentration of fluorophores, or by employing more robust fluorophores that are less prone to bleaching (e.g., Alexa Fluors, Seta Fluors, or DyLight Fluors). Some problems that may arise from this technique include autofluorescence, extraneous undesired specific fluorescence, and nonspecific fluorescence. Autofluorescence includes fluorescence emitted from the sample tissue or cell itself. Extraneous undesired specific fluorescence occurs when a targeted antigen is impure and contains antigenic contaminants. Nonspecific fluorescence involves the loss of a probe's specificity due to fluorophore, from improper fixation, or from a dried out specimen. is only limited to fixed (i.e | https://en.wikipedia.org/wiki?curid=553628 |
Immunofluorescence , dead) cells when structures within the cell are to be visualized because antibodies do not penetrate the cell membrane when reacting with fluorescent labels. Antigenic material must be fixed firmly on the site of its natural localization inside the cell. Intact antibodies can also be too large to dye cancer cells "in vivo". Their size results in slow tumor penetration and long circulating half-life. Research has been done investigating the use of diabodies to get around this limitation. Proteins in the supernatant or on the outside of the cell membrane can be bound by the antibodies; this allows for living cells to be stained. Depending on the fixative that is being used, proteins of interest might become cross-linked and this could result in either false positive or false negative signals due to non-specific binding. An alternative approach is using recombinant proteins containing fluorescent protein domains, e.g., green fluorescent protein (GFP). Use of such "tagged" proteins allows determination of their localization in live cells. Even though this seems to be an elegant alternative to immunofluorescence, the cells have to be transfected or transduced with the GFP-tag, and as a consequence they become at least S1 or above organisms that require stricter security standards in a laboratory. This technique involves altering the genetic information of cells. Many improvements to this method lie in the improvement of fluorescent microscopes and fluorophores | https://en.wikipedia.org/wiki?curid=553628 |
Immunofluorescence Super-resolution methods generally refer to a microscope's ability to produce resolution below the Abbe limit (a limit placed on light due to its wavelength). This diffraction limit is about 200-300 nm in the lateral direction and 500-700 nm in the axial direction. This limit is comparable or larger than some structures in the cell, and consequently, this limit prevented scientists from determining details in their structure. Super-resolution in fluorescence, more specifically, refers to the ability of a microscope to prevent the simultaneous fluorescence of adjacent spectrally identical fluorophores. This process effectively sharpens the point-spread function of the microscope. Examples of recently developed super-resolution fluorescent microscope methods include stimulated emission depletion (STED) microscopy, saturated structured-illumination microscopy (SSIM), fluorescence photoactivation localization microscopy (FPALM), and stochastic optical reconstruction microscopy (STORM). | https://en.wikipedia.org/wiki?curid=553628 |
Poling (metallurgy) Poling is a metallurgical method employed in the purification of copper which contains copper oxide as an impurity and also in the purification of tin ("Sn") which contains tin oxide (stannic oxide or "SnO") as an impurity. The impure metal, usually in the form of molten blister copper, is placed in an anode furnace for two stages of refining. In the first stage, sulphur and iron are removed by gently blowing air through the molten metal to form iron oxides and sulfur dioxide. The iron oxides are skimmed or poured off the top of the copper and the gaseous sulfur dioxide exits the furnace via the off-gas system. Once the first "oxidation" stage is complete, the second stage ("reduction" or "poling") begins. This involves using a reducing agent, normally natural gas or diesel (but ammonia, liquid petroleum gas, and naphtha can also be used), to react with the oxygen in the copper oxide to form copper . In the past, freshly cut ("green") trees were used as wooden poles. The sap in these poles acted as the reducing agent. The heat of the copper makes the pole emit wood gas(CO and H) that reduces the cuprous oxide to copper. It was the use of these greenwood poles gave rise to the term "poling." Care must be taken to avoid removing too much of the oxygen from the anode copper, as this will cause other impurities to change from their oxide to metallic states and they will remain in solid solution in the copper, reduce its conductivity and change its physical properties | https://en.wikipedia.org/wiki?curid=553679 |
Poling (metallurgy) Also upper surface can be covered with coke to prevent reoxidation of metal. | https://en.wikipedia.org/wiki?curid=553679 |
Pierre Berthier (; 3 July 1782, Nemours, Seine-et-Marne – 24 August 1861) was a French geologist and mining engineer. was born in Nemours. After studying at the École Polytechnique, he went to the École des Mines, where he became chief of the laboratory in 1816. In 1821, while working in the village of Les Baux-de-Provence, in southern France, he discovered the rock bauxite, named for the place of its discovery. He also discovered the mineral Berthierite, which was named after him. In addition to numerous contributions in mineralogy and mining, Berthier is also noted for his research into blast furnaces and for the utilization of phosphates by plants. The detailed register of homosexuals, then maintained by the Paris police prefecture, mention him as a lover of soldiers. was elected a member of the Académie des Sciences in 1825. In 1828, he became a "chevalier" of the Legion of Honor. His name is one of the 72 names inscribed on the Eiffel Tower. | https://en.wikipedia.org/wiki?curid=555120 |
Potential evaporation (PE) or potential evapotranspiration (PET) is defined as the amount of evaporation that would occur if a sufficient water source were available. If the actual evapotranspiration is considered the net result of atmospheric demand for moisture from a surface and the ability of the surface to supply moisture, then PET is a measure of the demand side. Surface and air temperatures, insolation, and wind all affect this. A dryland is a place where annual potential evaporation exceeds annual precipitation. formula_1 Where formula_2 is the estimated potential evapotranspiration (mm/month) formula_3 is the average daily temperature (degrees Celsius; if this is negative, use formula_4) of the month being calculated formula_5 is the number of days in the month being calculated formula_6 is the average day length (hours) of the month being calculated formula_7 formula_8 is a heat index which depends on the 12 monthly mean temperatures formula_9. Somewhat modified forms of this equation appear in later publications (1955 and 1957) by Thornthwaite and Mather. The Penman equation describes evaporation (E) from an open water surface, and was developed by Howard Penman in 1948. Penman's equation requires daily mean temperature, wind speed, air pressure, and solar radiation to predict E. Simpler Hydrometeorological equations continue to be used where obtaining such data is impractical, to give comparable results within specific contexts, e.g. humid vs arid climates | https://en.wikipedia.org/wiki?curid=557896 |
Potential evaporation The Penman–Monteith equation equation refines weather based potential evapotranspiration (PET) estimates of vegetated land areas. It is widely regarded as one of the most accurate models, in terms of estimates. The Priestley–Taylor equation equation was developed as a substitute to the Penman–Monteith equation to remove dependence on observations. For Priestley–Taylor, only radiation (irradiance) observations are required. This is done by removing the aerodynamic terms from the Penman–Monteith equation and adding an empirically derived constant factor, formula_10. The underlying concept behind the Priestley–Taylor model is that an air mass moving above a vegetated area with abundant water would become saturated with water. In these conditions, the actual evapotranspiration would match the Penman rate of potential evapotranspiration. However, observations revealed that actual evaporation was 1.26 times greater than potential evaporation, and therefore the equation for actual evaporation was found by taking potential evapotranspiration and multiplying it by formula_10. The assumption here is for vegetation with an abundant water supply (i.e. the plants have low moisture stress). Areas like arid regions with high moisture stress are estimated to have higher formula_10 values. The assumption that an air mass moving over a vegetated surface with abundant water saturates has been questioned later | https://en.wikipedia.org/wiki?curid=557896 |
Potential evaporation The lowest and turbulent part of the atmosphere, the atmospheric boundary layer, is not a closed box, but constantly brings in dry air from higher up in the atmosphere towards the surface. As water evaporates more easily into a dry atmosphere, evapotranspiration is enhanced. This explains the larger than unity value of the Priestley-Taylor parameter formula_10. The proper equilibrium of the system has been derived and involves the characteristics of the interface of the atmospheric boundary layer and the overlying free atmosphere. | https://en.wikipedia.org/wiki?curid=557896 |
Lactococcus virus P008 is a phage specific to "Lactococcus lactis", a lactic acid bacteria used in the first stage of making cheese. P008 and related species are responsible for important loss each year in cheese factories. | https://en.wikipedia.org/wiki?curid=559368 |
Earth pigment Earth pigments are naturally occurring minerals containing metal oxides, principally iron oxides and manganese oxides, that have been used since prehistoric times as pigments. The primary types are ochre, sienna and umber. Earth pigments are known for their fast drying time in oil painting, relative inexpensiveness, and lightfastness. Cave paintings done in sienna still survive today. After mining, the mineral used for making a pigment is ground to a very fine powder (if not already in the form of clay), washed to remove water-soluble components, dried, and ground again to powder. For some pigments, notably sienna and umber, the color can be deepened by heating (calcination) in a process known as "burning", although it does not involve oxidation but instead dehydration. | https://en.wikipedia.org/wiki?curid=561873 |
Biogenic substance A biogenic substance is a product made by or of life forms. The term encompasses constituents, secretions, and metabolites of plants or animals. In context of molecular biology, biogenic substances are referred to as biomolecules. An abiogenic substance or process does not result from the present or past activity of living organisms. Abiogenic products may, e.g., be minerals, other inorganic compounds, as well as simple organic compounds (e.g. extraterrestrial methane, see also abiogenesis). | https://en.wikipedia.org/wiki?curid=563239 |
Crystalloluminescence is the effect of luminescence produced during crystallization. The phenomena was first reported in the 1800s from the rapid crystallization of potassium sulfate from an aqueous solution. | https://en.wikipedia.org/wiki?curid=563728 |
Expression vector An expression vector, otherwise known as an expression construct, is usually a plasmid or virus designed for gene expression in cells. The vector is used to introduce a specific gene into a target cell, and can commandeer the cell's mechanism for protein synthesis to produce the protein encoded by the gene. Expression vectors are the basic tools in biotechnology for the production of proteins. The vector is engineered to contain regulatory sequences that act as enhancer and promoter regions and lead to efficient transcription of the gene carried on the expression vector. The goal of a well-designed expression vector is the efficient production of protein, and this may be achieved by the production of significant amount of stable messenger RNA, which can then be translated into protein. The expression of a protein may be tightly controlled, and the protein is only produced in significant quantity when necessary through the use of an inducer, in some systems however the protein may be expressed constitutively. "Escherichia coli" is commonly used as the host for protein production, but other cell types may also be used. An example of the use of expression vector is the production of insulin, which is used for medical treatments of diabetes. An expression vector has features that any vector may have, such as an origin of replication, a selectable marker, and a suitable site for the insertion of a gene like the multiple cloning site | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector The cloned gene may be transferred from a specialized cloning vector to an expression vector, although it is possible to clone directly into an expression vector. The cloning process is normally performed in "Escherichia coli". Vectors used for protein production in organisms other than "E.coli" may have, in addition to a suitable origin of replication for its propagation in "E. coli", elements that allow them to be maintained in another organism, and these vectors are called shuttle vectors. An expression vector must have elements necessary for gene expression. These may include a promoter, the correct translation initiation sequence such as a ribosomal binding site and start codon, a termination codon, and a transcription termination sequence. There are differences in the machinery for protein synthesis between prokaryotes and eukaryotes, therefore the expression vectors must have the elements for expression that are appropriate for the chosen host. For example, prokaryotes expression vectors would have a Shine-Dalgarno sequence at its translation initiation site for the binding of ribosomes, while eukaryotes expression vectors would contain the Kozak consensus sequence. The promoter initiates the transcription and is therefore the point of control for the expression of the cloned gene. The promoters used in expression vector are normally inducible, meaning that protein synthesis is only initiated when required by the introduction of an inducer such as IPTG | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector Gene expression however may also be constitutive (i.e. protein is constantly expressed) in some expression vectors. Low level of constitutive protein synthesis may occur even in expression vectors with tightly controlled promoters. After the expression of the gene product, it is usually necessary to purify the expressed protein; however, separating the protein of interest from the great majority of proteins of the host cell can be a protracted process. To make this purification process easier, a purification tag may be added to the cloned gene. This tag could be histidine (His) tag, other marker peptides, or a fusion partners such as glutathione S-transferase or maltose-binding protein. Some of these fusion partners may also help to increase the solubility of some expressed proteins. Other fusion proteins such as green fluorescent protein may act as a reporter gene for the identification of successful cloned genes, or they may be used to study protein expression in cellular imaging. The expression vector is transformed or transfected into the host cell for protein synthesis. Some expression vectors may have elements for transformation or the insertion of DNA into the host chromosome, for example the "vir" genes for plant transformation, and integrase sites for chromosomal integration . Some vectors may include targeting sequence that may target the expressed protein to a specific location such as the periplasmic space of bacteria | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector Different organisms may be used to express a gene's target protein, and the expression vector used will therefore have elements specific for use in the particular organism. The most commonly used organism for protein production is the bacterium "Escherichia coli". However, not all proteins can be successfully expressed in "E. coli", or be expressed with the correct form of post-translational modifications such as glycosylations, and other systems may therefore be used. The expression host of choice for the expression of many proteins is "Escherichia coli" as the production of heterologous protein in "E. coli" is relatively simple and convenient, as well as being rapid and cheap. A large number of "E. coli" expression plasmids are also available for a wide variety of needs. Other bacteria used for protein production include "Bacillus subtilis". Most heterologous proteins are expressed in the cytoplasm of "E. coli". However, not all proteins formed may be soluble in the cytoplasm, and incorrectly folded proteins formed in cytoplasm can form insoluble aggregates called inclusion bodies. Such insoluble proteins will require refolding, which can be an involved process and may not necessarily produce high yield. Proteins which have disulphide bonds are often not able to fold correctly due to the reducing environment in the cytoplasm which prevents such bond formation, and a possible solution is to target the protein to the periplasmic space by the use of an N-terminal signal sequence | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector Another possibility is to manipulate the redox environment of the cytoplasm. Other more sophisticated systems are also being developed; such systems may allow for the expression of proteins previously thought impossible in "E. coli", such as glycosylated proteins. The promoters used for these vector are usually based on the promoter of the "lac" operon or the T7 promoter, and they are normally regulated by the "lac" operator. These promoters may also be hybrids of different promoters, for example, the Tac-Promoter is a hybrid of "trp" and "lac" promoters. Note that most commonly used "lac" or "lac"-derived promoters are based on the "lac"UV5 mutant which is insensitive to catabolite repression. This mutant allows for expression of protein under the control of the "lac" promoter when the growth medium contains glucose since glucose would inhibit gene expression if wild-type "lac" promoter is used. Presence of glucose nevertheless may still be used to reduce background expression through residual inhibition in some systems. Examples of "E. coli" expression vectors are the pGEX series of vectors where glutathione S-transferase is used as a fusion partner and gene expression is under the control of the tac promoter, and the pET series of vectors which uses a T7 promoter. It is possible to simultaneously express two or more different proteins in "E. coli" using different plasmids | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector However, when 2 or more plasmids are used, each plasmid needs to use a different antibiotic selection as well as a different origin of replication, otherwise one of the plasmids may not be stably maintained. Many commonly used plasmids are based on the ColE1 replicon and are therefore incompatible with each other; in order for a ColE1-based plasmid to coexist with another in the same cell, the other would need to be of a different replicon, e.g. a p15A replicon-based plasmid such as the pACYC series of plasmids. Another approach would be to use a single two-cistron vector or design the coding sequences in tandem as a bi- or poly-cistronic construct. A yeast commonly used for protein production is "Pichia pastoris". Examples of yeast expression vector in "Pichia" are the pPIC series of vectors, and these vectors use the AOX1 promoter which is inducible with methanol. The plasmids may contain elements for insertion of foreign DNA into the yeast genome and signal sequence for the secretion of expressed protein. Proteins with disulphide bonds and glycosylation can be efficiently produced in yeast. Another yeast used for protein production is "Kluyveromyces lactis" and the gene is expressed, driven by a variant of the strong lactase LAC4 promoter. "Saccharomyces cerevisiae" is particularly widely used for gene expression studies in yeast, for example in yeast two-hybrid system for the study of protein-protein interaction | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector The vectors used in yeast two-hybrid system contain fusion partners for two cloned genes that allow the transcription of a reporter gene when there is interaction between the two proteins expressed from the cloned genes. Baculovirus, a rod-shaped virus which infects insect cells, is used as the expression vector in this system. Insect cell lines derived from Lepidopterans (moths and butterflies), such as "Spodoptera frugiperda", are used as host. A cell line derived from the cabbage looper is of particular interest, as it has been developed to grow fast and without the expensive serum normally needed to boost cell growth. The shuttle vector is called bacmid, and gene expression is under the control of a strong promoter pPolh. Baculovirus has also been used with mammalian cell lines in the BacMam system. Baculovirus is normally used for production of glycoproteins, although the glycosylations may be different from those found in vertebrates. In general, it is safer to use than mammalian virus as it has a limited host range and does not infect vertebrates without modifications. Many plant expression vectors are based on the Ti plasmid of "Agrobacterium tumefaciens". In these expression vectors, DNA to be inserted into plant is cloned into the T-DNA, a stretch of DNA flanked by a 25-bp direct repeat sequence at either end, and which can integrate into the plant genome. The T-DNA also contains the selectable marker | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector The "Agrobacterium" provides a mechanism for transformation, integration of into the plant genome, and the promoters for its "vir" genes may also be used for the cloned genes. Concerns over the transfer of bacterial or viral genetic material into the plant however have led to the development of vectors called intragenic vectors whereby functional equivalents of plant genome are used so that there is no transfer of genetic material from an alien species into the plant. Plant viruses may be used as vectors since the "Agrobacterium" method does not work for all plants. Examples of plant virus used are the tobacco mosaic virus (TMV), potato virus X, and cowpea mosaic virus. The protein may be expressed as a fusion to the coat protein of the virus and is displayed on the surface of assembled viral particles, or as an unfused protein that accumulates within the plant. Expression in plant using plant vectors is often constitutive, and a commonly used constitutive promoter in plant expression vectors is the cauliflower mosaic virus (CaMV) 35S promoter. Mammalian expression vectors offer considerable advantages for the expression of mammalian proteins over bacterial expression systems - proper folding, post-translational modifications, and relevant enzymatic activity. It may also be more desirable than other eukaryotic non-mammalian systems whereby the proteins expressed may not contain the correct glycosylations | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector It is of particular use in producing membrane-associating proteins that require chaperones for proper folding and stability as well as containing numerous post-translational modifications. The downside, however, is the low yield of product in comparison to prokaryotic vectors as well as the costly nature of the techniques involved. Its complicated technology, and potential contamination with animal viruses of mammalian cell expression have also placed a constraint on its use in large-scale industrial production. Cultured mammalian cell lines such as the Chinese hamster ovary (CHO), COS, including human cell lines such as HEK and HeLa may be used to produce protein. Vectors are transfected into the cells and the DNA may be integrated into the genome by homologous recombination in the case of stable transfection, or the cells may be transiently transfected. Examples of mammalian expression vectors include the adenoviral vectors, the pSV and the pCMV series of plasmid vectors, vaccinia and retroviral vectors, as well as baculovirus. The promoters for cytomegalovirus (CMV) and SV40 are commonly used in mammalian expression vectors to drive gene expression. Non-viral promoter, such as the elongation factor (EF)-1 promoter, is also known. "E. coli" cell lysate containing the cellular components required for transcription and translation are used in this "in vitro" method of protein production | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector The advantage of such system is that protein may be produced much faster than those produced "in vivo" since it does not require time to culture the cells, but it is also more expensive. Vectors used for "E. coli" expression can be used in this system although specifically designed vectors for this system are also available. Eukaryotic cell extracts may also be used in other cell-free systems, for example, the wheat germ cell-free expression systems. Mammalian cell-free systems have also been produced. in an expression host is now the usual method used in laboratories to produce proteins for research. Most proteins are produced in "E. coli", but for glycosylated proteins and those with disulphide bonds, yeast, baculovirus and mammalian systems may be used. Most protein pharmaceuticals are now produced through recombinant DNA technology using expression vectors. These peptide and protein pharmaceuticals may be hormones, vaccines, antibiotics, antibodies, and enzymes. The first human recombinant protein used for disease management, insulin, was introduced in 1982. Biotechnology allows these peptide and protein pharmaceuticals, some of which were previously rare or difficult to obtain, to be produced in large quantity. It also reduces the risks of contaminants such as host viruses, toxins and prions | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector Examples from the past include prion contamination in growth hormone extracted from pituitary glands harvested from human cadavers, which caused Creutzfeldt–Jakob disease in patients receiving treatment for dwarfism, and viral contaminants in clotting factor VIII isolated from human blood that resulted in the transmission of viral diseases such as hepatitis and AIDS. Such risk is reduced or removed completely when the proteins are produced in non-human host cells. In recent years, expression vectors have been used to introduce specific genes into plants and animals to produce transgenic organisms, for example in agriculture it is used to produce transgenic plants. Expression vectors have been used to introduce a vitamin A precursor, beta-carotene, into rice plants. This product is called golden rice. This process has also been used to introduce a gene into plants that produces an insecticide, called Bacillus thuringiensis toxin or Bt toxin which reduces the need for farmers to apply insecticides since it is produced by the modified organism. In addition expression vectors are used to extend the ripeness of tomatoes by altering the plant so that it produces less of the chemical that causes the tomatoes to rot. There have been controversies over using expression vectors to modify crops due to the fact that there might be unknown health risks, possibilities of companies patenting certain genetically modified food crops, and ethical concerns. Nevertheless, this technique is still being used and heavily researched | https://en.wikipedia.org/wiki?curid=564380 |
Expression vector Transgenic animals have also been produced to study animal biochemical processes and human diseases, or used to produce pharmaceuticals and other proteins. They may also be engineered to have advantageous or useful traits. Green fluorescent protein is sometimes used as tags which results in animal that can fluoresce, and this have been exploited commercially to produce the fluorescent GloFish. Gene therapy is a promising treatment for a number of diseases where a "normal" gene carried by the vector is inserted into the genome, to replace an "abnormal" gene or supplement the expression of particular gene. Viral vectors are generally used but other nonviral methods of delivery are being developed. The treatment is still a risky option due to the viral vector used which can cause ill-effects, for example giving rise to insertional mutation that can result in cancer. However, there have been promising results. | https://en.wikipedia.org/wiki?curid=564380 |
Brian Heap Sir Robert Brian Heap, (born 27 February 1935) is a British biological scientist. He was educated at New Mills Grammar School in the Peak District, Derbyshire, and the University of Nottingham (where he earned his BSc and PhD). He also has an MA and a ScD from the University of Cambridge and Honorary DScs from Nottingham (1994), York (2001) and St Andrews (2007). Heap's primary research interest was in reproductive biology and the function of hormones in reproduction. His research into the control of pregnancy, birth and lactation led to important contributions in endocrine physiology and farm animal breeding. He has published on endocrine physiology, biotechnology, sustainable consumption and production, and science advice for policy makers. He was the Master of St Edmund's College, University of Cambridge from 1996 until 2004 and has been a Special Professor in Animal Physiology at the University of Nottingham since 1988 until 2016. He was elected a fellow of the Royal Society in 1989, and held the post of Royal Society Vice President and Foreign Secretary from 1996 to 2001. He was Executive Editor of the "Philosophical Transactions of the Royal Society, Series B" from 2004-2007. He is a founder member of the International Society for Science and Religion and an Associate of the Faraday Institute for Science and Religion | https://en.wikipedia.org/wiki?curid=566872 |
Brian Heap was President of the Institute of Biology (now Royal Society of Biology) 1996-1998, UK Representative on the European Science Foundation Strasbourg, 1994–97, a member of the Nuffield Council on Bioethics 1996-2001, UK Representative on the NATO Science Committee 1998-2005, member of the Scientific Advisory Panel for Emergency Responses (SAPER) at the Cabinet Office, Chairman of the Cambridge Genetics Knowledge Park and Public Health Genetics, 2002-2010, and President of the , 2010-2014. He was co-Project Leader of Biosciences for Farming in Africa, 2014-17, and Senior Adviser of Smart Villages from 2017. In 1994 he was awarded CBE, and in 2001 knighted for services to international science. On 8 October 2007, the Duke of Edinburgh opened three new buildings at St Edmund's College, Cambridge, one of which was named the "Building". | https://en.wikipedia.org/wiki?curid=566872 |
Kale (moon) Kale , also known as ', is a retrograde irregular satellite of Jupiter. It was discovered in 2001 by astronomers Scott S. Sheppard, D. Jewitt, and J. Kleyna, and was originally designated as '. Kale is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 22,409 Mm in 685.324 days, at an inclination of 165° to the ecliptic (166° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2011. It was named in August 2003 after Kale, one of the Charites (Greek Χάριτες, Latin "Gratiae", "Graces"), daughters of Zeus (Jupiter). Kale is the spouse of Hephaestus according to some authors (although most have Aphrodite play that role). It belongs to the Carme group, made up of irregular retrograde moons orbiting Jupiter at a distance ranging between 23 and 24 Gm and at an inclination of about 165°. | https://en.wikipedia.org/wiki?curid=571107 |
Celestial event A celestial event is an astronomical phenomenon of interest that involves one or more celestial objects. Some examples of celestial events are the cyclical phases of the Moon, solar and lunar eclipses, transits and occultations, planetary oppositions and conjunctions, meteor showers, and comet flybys, solstices and equinoxes. | https://en.wikipedia.org/wiki?curid=573924 |
Jean Bricmont (; born 12 April 1952) is a Belgian theoretical physicist and philosopher of science. Professor at the Catholic University of Louvain (UCLouvain), he works on renormalization group and nonlinear differential equations. Since 2004, He is a member of the Division of Sciences of the Royal Academy of Belgium. Bricmont is mostly known to the non-academic audience as a rationalist activist who partners with American intellectuals with similar views. He has notably criticized postmodernist views of science along with Alan Sokal, with whom he wrote "Fashionable Nonsense" (1997). He has also criticized imperialism and defended freedom of expression along with Noam Chomsky. | https://en.wikipedia.org/wiki?curid=574226 |
MIRACL MIRACL, or Mid-Infrared Advanced Chemical Laser, is a directed energy weapon developed by the US Navy. It is a deuterium fluoride laser, a type of chemical laser. The laser first became operational in 1980. It can produce over a megawatt of output for up to 70 seconds, making it the most powerful continuous wave (CW) laser in the US. Its original goal was to be able to track and destroy anti-ship cruise missiles, but in later years it was used to test phenomenologies associated with national anti-ballistic and anti-satellite laser weapons. Originally tested at a contractor facility in California, as of the later 1990s and early 2000s, it was located at a facility () in the White Sands Missile Range in New Mexico. The beam size in the resonator is about 21 cm (8.3 in) high and 3 cm (1.2 in) wide. The beam is then reshaped to a 14 x 14 cm (5.5 in x 5.5 in) square. Amid much controversy in October 1997, was tested against MSTI-3, a US Air Force satellite at the end of its original mission in orbit at a distance of 432 km (268 mi). failed during the test and was damaged and the Pentagon claimed mixed results for other portions of the test. A second, lower-powered chemical laser was able to temporarily blind the MSTI-3 sensors during the test. | https://en.wikipedia.org/wiki?curid=578365 |
Cosmography is the science that maps the general features of the cosmos or universe, describing both heaven and Earth (but without encroaching on geography or astronomy). The 14th-century work "'Aja'ib al-makhluqat wa-ghara'ib al-mawjudat" by Persian physician Zakariya al-Qazwini is considered to be an early work of cosmography. Traditional Hindu, Buddhist and Jain cosmography schematize a universe centered on Mount Meru surrounded by rivers, continents and seas. These cosmographies posit a universe being repeatedly created and destroyed over time cycles of immense lengths. In 1551, Martín Cortés de Albacar, from Zaragoza, Spain, published "Breve compendio de la esfera y del arte de navegar". Translated into English and reprinted several times, the work was of great influence in Britain for many years. He proposed spherical charts and mentioned magnetic deviation and the existence of magnetic poles. Peter Heylin's 1652 book "Cosmographie" (enlarged from his "Microcosmos" of 1621) was one of the earliest attempts to describe the entire world in English, and being the first known description of Australia and among the first of California. The book has 4 sections, examining the geography, politics, and cultures of Europe, Asia, Africa, and America, with an addendum on "Terra Incognita", including Australia, and extending to Utopia, Fairyland, and the "Land of Chivalrie" | https://en.wikipedia.org/wiki?curid=585226 |
Cosmography In 1659, Thomas Porter published a smaller, but extensive "Compendious Description of the Whole World", which also included a chronology of world events from Creation forward. These were all part of a major trend in the European Renaissance to explore (and perhaps comprehend) the known world. The word was also commonly used by Buckminster Fuller in his lectures. In astrophysics, the term "cosmography" is beginning to be used to describe attempts to determine the large-scale matter distribution and kinematics of the observable universe, dependent on the Friedmann–Lemaître–Robertson–Walker metric but independent of the temporal dependence of the scale factor on the matter/energy composition of the Universe. In recent decades, the cosmic accelerating expansion is a discovered cosmological landmark. It was previously unknown how a number of dynamical mechanisms are proposed to give explanation to a mysterious phenomenon in cosmography. Although, the essence of it is still not known there are theoretical attempts that attempt to give explanation through modified gravity and dark energy. One of the first paradigms is based on a belief that there is a cosmic opponent named a dark energy. Many observations focus on the high-redshift region. For example, the supernova in a joint light-curve analysis (JLA) compilation can span the redshift region up to 1.3; the cosmic microwave background (CMB) even can retrospect to the very early universe at z ∼ 1100 | https://en.wikipedia.org/wiki?curid=585226 |
Cosmography To legitimate the expansion at high redshift, they introduced an improved redshift parametrization y = z/(1 + z) cosmography in the y-based expansion is mathematically safe and useful, because of 0 < y < 1, even for the high redshift. Later, some other methods of redshift were also proposed There are also other forms of recently found cosmography such as ‘urban cosmography’ which are illustrations of urban scenes that describe the physical characteristics of the places that are depicted in the illustrations. The representation of the physical characteristics of the urban scenes express a wide range of beliefs in an implicit form. These beliefs represent their surrounding world and the ties between their surroundings and local systems, institutions and human actions they face. Therefore, the illustration of a city represents a form of cosmography that came from early modern artisans in an attempt to understand and represent the contours of the world, that were both known and unknown. The ‘urban cosmography’ uses the perspective to document the city's position inside a universe that continually evolves around it. Maps, posters and birds eye views of the city document this ‘urban cosmography’. An example of this ‘urban cosmography’ is "The Ideal City" which is thought to have been painted by Fran Carnevale circa 1480. "The Ideal City" is a panel painting which was part of three similar paintings that belonged to the Duke of Urbino | https://en.wikipedia.org/wiki?curid=585226 |
Cosmography The image shown in this painting is one that represents a world that is beyond the period's urban reality's framework. However, the architectural forms found in the painting and the placement in the painted city were an accurate representation of what was the order of things at the time. The perceived order of things at the time had a perfected feel but this representation still managed to illustrate and maintain its grasp of future realization and the illustration. That is Fra Carnevale's ‘urban cosmography’ stating the definition of ‘urban cosmography’ in which it is used as a tool for the perspective to document the city's position inside a universe that continually evolves around it. There are many other visual references throughout history and art which are also representations of ‘urban cosmography’. These have offered a wide view of cities through time and the perspective of the people who live in them. | https://en.wikipedia.org/wiki?curid=585226 |
Capillary number In fluid dynamics, the capillary number (Ca) is a dimensionless quantity representing the relative effect of viscous drag forces versus surface tension forces acting across an interface between a liquid and a gas, or between two immiscible liquids. For example, an air bubble in a liquid flow tends to be deformed by the friction of the liquid flow due to viscosity effects, but the surface tension forces tend to minimize the surface area. The capillary number is defined as: where formula_2 is the dynamic viscosity of the liquid, formula_3 is a characteristic velocity and formula_4 is the surface tension or interfacial tension between the two fluid phases. Being a dimensionless quantity, the capillary number's value does not depend on the system of units. In the petroleum industry, capillary number is denoted formula_5 instead of formula_6. For low capillary numbers (a rule of thumb says less than 10), flow in porous media is dominated by capillary forces, whereas for high capillary numbers the capillary forces are negligible compared to the viscous forces. Flow through the pores in an oil field reservoir have capillary number on the order of 10, whereas flow of oil through an oil well drill pipe has a capillary number on the order of 1. The capillary number plays a role in the dynamics of capillary flow; in particular, it governs the dynamic contact angle of a flowing droplet at an interface. | https://en.wikipedia.org/wiki?curid=585453 |
Carl Jakob Sundevall (22 October 1801, Högestad – 2 February 1875) was a Swedish zoologist. Sundevall studied at Lund University, where he became a Ph.D. in 1823. After traveling to East Asia, he studied medicine, graduating as Doctor of Medicine in 1830. He was employed at the Swedish Museum of Natural History, Stockholm from 1833, and was professor and keeper of the vertebrate section from 1839 to 1871. He wrote "Svenska Foglarna" (1856–87) which described 238 species of birds observed in Sweden. He classified a number of birds collected in southern Africa by Johan August Wahlberg. In 1835, he developed a phylogeny for the birds based on the muscles of the hip and leg that contributed to later work by Thomas Huxley. He then went on to examine the arrangement of the deep plantar tendons in the bird's foot. This latter information is still used by avian taxonomists. Sundevall was also an entomologist and arachnologist, for which (for the latter field) in 1833 he published an early catalog "Conspectus Arachnidum". Much later in 1862, he wrote a monograph proposing a universal phonetic alphabet, "Om phonetiska bokstäver". Sundevall is commemorated in the scientific names of four species of reptiles: "Elapsoidea sundevalli, Leptotyphlops sundewalli, Mochlus sundevalli", and "Prosymna sundevalli". | https://en.wikipedia.org/wiki?curid=588214 |
Trinculo (moon) Trinculo is a retrograde irregular satellite of Uranus. It was discovered by a group of astronomers led by Holman, "et al." on 13 August 2001, and given the temporary designation S/2001 U 1. Confirmed as Uranus XXI, it was named after the drunken jester Trinculo in William Shakespeare's play "The Tempest". Trinculo is the smallest of Uranus' 27 moons and is approximately only 18 km wide and is roughly the size of Manhattan Island. | https://en.wikipedia.org/wiki?curid=589883 |
Alpine garden An alpine garden (or alpinarium, alpinum) is a domestic or botanical garden specialising in the collection and cultivation of alpine plants growing naturally at high altitudes around the world, such as in the Caucasus, Pyrenees, Rocky Mountains, Alps, Himalayas and Andes. An alpine garden tries to imitate the conditions of the plants' place of origin. One example of this is using large stones and gravel beds, rather than the soil that naturally grows there. Though the plants can often cope with low temperatures, they dislike standing in damp soil during the winter months. The soil used is typically poor (sandy) but extremely well-drained. One of the main obstacles in developing an alpine garden is the unnatural conditions which exist in some areas, particularly mild or severe winters and heavy rainfall, such as those present in the United Kingdom and Ireland. This can be avoided by growing the plants in an alpine house or unheated greenhouse, which tries to reproduce the ideal conditions. The first true alpine garden was created by Anton Kerner von Marilaun in 1875 on the Blaser Mountain, in Tyrol, Austria, at an altitude of . Typical plants found in an alpine garden include: | https://en.wikipedia.org/wiki?curid=594717 |
Dry distillation is the heating of solid materials to produce gaseous products (which may condense into liquids or solids). The method may involve pyrolysis or thermolysis, or it may not (for instance, a simple mixture of ice and glass could be separated without breaking any chemical bonds, but organic matter contains a greater diversity of molecules, some of which are likely to break). If there are no chemical changes, just phase changes, it resembles classical distillation, although it will generally need higher temperatures. in which chemical changes occur is a type of destructive distillation or cracking. The method has been used to obtain liquid fuels from coal and wood. It can also be used to break down mineral salts such as sulfates () through thermolysis, in this case producing sulfur dioxide (SO) or sulfur trioxide (SO) gas which can be dissolved in water to obtain sulfuric acid. By this method sulfuric acid was first identified and artificially produced. When substances of vegetable origin, e.g. coal, oil shale, peat or wood, are heated in the absence of air (dry distillation), they decompose into gas, liquid products and coke/charcoal. The yield and chemical nature of the decomposition products depend on the nature of the raw material and the conditions under which the dry distillation is done. Decomposition within a temperature range of 450 to about 600°C is called carbonization or low-temperature degassing. At temperatures above 900°C, the process is called coking or high-temperature degassing | https://en.wikipedia.org/wiki?curid=595145 |
Dry distillation If coal is gasified to make coal gas or carbonized to make coke then Coal tar is among the by-products. When wood is heated above 270°C it begins to carbonize. If air is absent, the final product (since there is no oxygen present to react with the wood) is charcoal. If air (which contains oxygen) is present, the wood will catch fire and burn when it reaches a temperature of about 400–500°C and the fuel product is wood ash. If wood is heated away from air, first the moisture is driven off. Until this is complete, the wood temperature remains at about 100–110°C. When the wood is dry its temperature rises, and at about 270°C, it begins to spontaneously decompose. This is the well known exothermic reaction which takes place in charcoal burning. At this stage evolution of the by-products of wood carbonization starts. These substances are given off gradually as the temperature rises and at about 450°C the evolution is complete. The solid residue, charcoal, is mainly carbon (about 70%) and small amounts of tarry substances which can be driven off or decomposed completely only by raising the temperature to above about 600°C. In the common practice of charcoal burning using internal heating of the charged wood by burning a part of it, all the by-product vapors and gas escapes into the atmosphere as smoke | https://en.wikipedia.org/wiki?curid=595145 |
Dry distillation The by-products can be recovered by passing the off-gases through a series of water to yield so-called wood vinegar (pyroligneous acid) and the non-condensible wood gas passes on through the condenser and may be burned to provide heat. The wood gas is only usable as fuel and consists typically of 17% methane; 2% hydrogen; 23% carbon monoxide; 38% carbon dioxide; 2% oxygen and 18% nitrogen. It has a gas calorific value of about 10.8 MJoules per m (290 BTU/cu.ft.) i.e. about one third the value of natural gas. When deciduous tree woods are subjected to distillation, the products are methanol (wood alcohol) and charcoal. The distillation of pine wood causes Pine tar and pitch to drip away from the wood and leave behind charcoal. Birch tar from birch bark is a particularly fine tar, known as "Russian oil", suitable for leather protection. The by-products of wood tar are turpentine and charcoal. Tar kilns are dry distillation ovens, historically used in Scandinavia for producing tar from wood. They were built close to the forest, from limestone or from more primitive holes in the ground. The bottom is sloped into an outlet hole to allow the tar to pour out. The wood is split into dimensions of a finger, stacked densely, and finally covered tight with dirt and moss. If oxygen can enter, the wood might catch fire, and the production would be ruined. On top of this, a fire is stacked and lit. After a few hours, the tar starts to pour out and continues to do so for a few days. | https://en.wikipedia.org/wiki?curid=595145 |
Rudolf Trümpy (16 August 1921 – 30 January 2009) was a Swiss geologist, who was born in the small Swiss town of Glarus. He graduated from the ETH Zürich in the late 1940s with a thesis titled: “Der Lias der Glarner Alpen”. From 1947 to 1953 he spent his post-doctoral years in Lausanne before being appointed professor at ETH Zürich in 1953. He would remain there until 1986. His research mainly concentrated on alpine geology. However, he also published papers on extra-alpine regions like Greenland, the Montagne Noire and the Sahara. He was the author of the reference book "Geology of Switzerland". Trümpy is the recipient of numerous awards and prizes including the Wollaston Medal and the Penrose Medal. In 1978 he was elected a Foreign Associate of the United States National Academy of Sciences. He is also a member of the French Academy of Sciences. Many stratigraphic formations in the western Alps were first described by Trümpy. For example, the Couches de l’Aroley, the Couches des Marmontains and the Couches de St Cristoph. | https://en.wikipedia.org/wiki?curid=598258 |
BD (company) Becton, Dickinson and Company, commonly known as BD, is an American medical technology company that manufactures and sells medical devices, instrument systems, and reagents. BD also provides consulting and analytics services in certain geographies. Founded in 1897 and headquartered in Franklin Lakes, New Jersey, BD employs nearly 70,000 people in more than 50 countries throughout the world. In the fiscal year ending September 30, 2019, more than 40% of BD sales were generated from non-U.S. markets. The company's customers include health care institutions, science researchers, clinical laboratories, the pharmaceutical industry, and the general public. BD was one of the first companies to sell U.S.-made glass syringes. It was also a pioneer in the production of hypodermic needles. Today, BD is divided into three segments: BD Medical, BD Life Sciences and BD Interventional. BD is ranked #195 in the 2019 Fortune 500 list. The firm in October 2014 agreed to acquire CareFusion for a price of $12.2 billion in cash and stock. In April 2017 Becton Dickinson agreed to acquire C. R. Bard for $24 billion. BD was founded in 1897 by Maxwell W. Becton and Fairleigh S. Dickinson, two American businessmen who met on a sales trip. The same year the company made its first sale, a Luer-all-glass syringe that sold for $2.50. In 1898, BD acquired its first patent for a medical product. In 1899 the company introduced its first logo which was meant to symbolize guaranteed superior quality of the products provided by BD | https://en.wikipedia.org/wiki?curid=598704 |
BD (company) In 1904, BD acquired the Philadelphia Surgical Company. This very first acquisition and other early acquisitions significantly expanded the company's manufacturing ability and product offering. Two years later, BD incorporated in the state of New Jersey and built a manufacturing facility in East Rutherford, the first in the U.S. created specifically for the production of thermometers, hypodermic needles, and syringes. In 1924, BD manufactured its first syringe designed specifically for insulin injection. One year later, BD introduced the BD Yale Luer-Lok Syringe, designed and patented by Fairleigh S. Dickinson, Sr. It provided a simple and secure method of attaching and removing the needle to and from the syringe. Today, Luer taper connectors are the standard for syringes in the U.S. In 1947 Joseph Kleiner developed the Evacutainer—a device used to draw blood by vacuum through a needle into a test tube. This product eventually evolved to become the BD Vacutainer Blood Collection system. In 1948, BD faced new leadership as Fairleigh S. Dickinson, Jr. and Henry P. Becton, sons of the founders, took over the company. Their 24-year tenure was a time of rapid development for BD. The company grew within the U.S. as well as internationally. In 1949, it opened its first manufacturing site outside of New Jersey in Columbus, Nebraska. In 1961, it established a manufacturing facility in Canaan, Connecticut. BD also soon expanded to Canada (1951), Mexico (1952), France (1955), and Brazil (1956). The tenure of Fairleigh S | https://en.wikipedia.org/wiki?curid=598704 |
BD (company) Dickinson, Jr. and Henry P. Becton was also a time of significant product innovation. In 1950, BD's first sterile disposable product, a blood collection set, was developed and sold to the American Red Cross. In 1954, BD introduced the first completely disposable syringe made of glass: BD Hypak. This innovative product was used in a large-scale field test of the polio vaccine developed by Dr. Jonas Salk. One year later, BD entered the microbiology field through the acquisition of the Baltimore Biological Laboratory. In 1961, the company introduced its disposable BD Plastipak syringe. Under the new leadership the company also went public (1962) and appeared for the first time in the Fortune 500 list (1970). In 1973, BD added another U.S. facility — a research center in Durham, North Carolina in Research Triangle Park. The center was established to help the company meet United States Environmental Protection Agency (EPA) requirements, research improved manufacturing and process methods, and develop future innovative technologies. In 1975, BD Pharmaceutical Systems Europe acquired an important patent for a prefilled syringe injecting heparin. In 1980, BD developed its first automated system for mycobacteria testing—the BD BACTEC 460TB System. The next year brought significant signs of the company's development as sales surpassed the $1 billion milestone and a new plant in Plymouth, England was constructed to serve the European markets | https://en.wikipedia.org/wiki?curid=598704 |
BD (company) Five years later BD moved its corporate headquarters to Franklin Lakes, New Jersey (current HQ location.) Also in 1986, BD acquired Fabersanitas Industrial, a major Spanish syringe manufacturer as well as Deseret Medical, a vascular access devices manufacturer. The last three years of the 1980s also showed growth in Asia (manufacturing facilities in Singapore and Japan.) Furthermore, BD became the first company to introduce a safety-engineered syringe, the BD Safety-Lok (1988), and acquired the Beaver Blade Company, a manufacturer of high-quality surgical blades. The first half of the next decade was very important to BD's development. The company opened a central distribution center in Temse, Belgium (1992) and entered India and China (1995). BD also introduced a device that offered needle stick protection following blood-drawing procedures, the BD Vacutainer Safety-Lok Blood Collection Set. In 1999 BD announced its new corporate identity. Numerous independent brand names were replaced by a single name: BD. In addition, the company symbol that is used today was introduced. BD also named Edward J. Ludwig as the company's president. Ludwig was also named Chief Executive Officer (2000) and Chairman of the Board of Directors (2002). On February 9, 1999, BD announced the acquisition of Biometric Imaging, Inc. (BMI), a privately held company serving the transfusion medicine, infectious diseases, and oncology markets | https://en.wikipedia.org/wiki?curid=598704 |
BD (company) On December 20, 2000, BD signed an agreement to acquire Gentest Corporation, a privately held company serving the life sciences market in the areas of drug metabolism and toxicology testing of pharmaceutical candidates. During that time, BD also got heavily involved in global health issues announcing a five-year maternal and neonatal tetanus worldwide elimination partnership with UNICEF (1999), launching the BD Safety Compliance Initiative (2000), and pledging $1 million contribution to the International AIDS Vaccine Initiative (2002.) In 2003 and 2004, BD introduced several innovative products: BD FACSAria Cell Sorter—the first entirely new instrument in the next-generation portfolio of flow cytometers (2003), BD Accuspray—a nasal drug delivery system for administering vaccines (2003), BD.id—a patient identification system designed to limit the potential for medical errors in specimen collection (2003), and the world's first "intelligent" insulin pump and glucose monitoring system, a wireless system consisting of a Medtronic MiniMed Paradigm 512 Insulin Pump and Paradigm Link Blood Glucose Monitor, co-developed with BD. In the beginning of the 21st century BD also invested in growing its business by acquiring several strategically important companies. In 2001, it acquired the Gentest Corporation, a leading in drug metabolism and toxicology testing company | https://en.wikipedia.org/wiki?curid=598704 |
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