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Small interfering RNA In some cases, the endonucleolytic cleavage of the phosphodiester backbone may be suppressed by mismatches of siRNA and target mRNA near the cleaving site. Other times, the Argonaute proteins of the RISC lack endonuclease activity even when the target mRNA and siRNA are perfectly paired. In such c... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA One promising method of reducing the nonspecific effects is to convert the siRNA into a microRNA. MicroRNAs occur naturally, and by harnessing this endogenous pathway it should be possible to achieve similar gene knockdown at comparatively low concentrations of resulting siRNAs. This should minimi... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA However recently a large Phase III trial of PEGylated RNA aptamer against factor IX had to be discontinued by Regado Biosciences because of a severe anaphylactic reaction to the PEG part of the RNA. This reaction led to death in some cases and raises significant concerns about siRNA delivery when ... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA Chemical modification of siRNA can also inadvertently result in loss of single-nucleotide specificity. siRNAs and their role in post-transcriptional gene silencing (PTGS) were first discovered in plants by David Baulcombe's group at the Sainsbury Laboratory in Norwich, England and reported in "Sci... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA Delivering pure DNA to target organisms is challenging because its large size and structure prevents it from diffusing readily across membranes. siRNA oligos circumvent this problem due to their small size of 21-23 oligos. This allows delivery via nano-scale delivery vehicles called nanovectors. A... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA Phase I results of the first two therapeutic RNAi trials (indicated for age-related macular degeneration, aka AMD) reported at the end of 2005 that siRNAs are well tolerated and have suitable pharmacokinetic properties. In a phase 1 clinical trial, 41 patients with advanced cancer metastasised to ... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA This method is advantageous because it can deliver siRNA to most types of cells, has high efficiency and reproducibility, and is offered commercially. The most common commercial reagents for transfection of siRNA are Lipofectamine and Neon Transfection. However it is not compatible with all cell t... | https://en.wikipedia.org/wiki?curid=584617 |
Small interfering RNA Delivering this siRNA from DNA templates can be done through several recombinant viral vectors based on retrovirus, adeno-associated virus, adenovirus, and lentivirus. The latter is the most efficient virus that stably delivers siRNA to target cells as it can transduce nondividing cells as well as... | https://en.wikipedia.org/wiki?curid=584617 |
Chemical Abstracts Service (CAS) is a division of the American Chemical Society. It is a source of chemical information. CAS is located in Columbus, Ohio, United States. Chemical Abstracts is a periodical index that provides numerous tools such as SciFinder as well as tagged keywords, summaries, indexes of disclosures,... | https://en.wikipedia.org/wiki?curid=585185 |
Chemical Abstracts Service The assignment of chemical names is done according to the chemical nomenclature rules for "CA" index names, which is slightly different from the internationally standard IUPAC names, according to the rules of IUPAC. CAS databases are available via two principal database systems, STN, and SciF... | https://en.wikipedia.org/wiki?curid=585185 |
Chemical Abstracts Service The range is from 1907 to the present, including both serial and non-serial scientific and technical publications. The database is updated quarterly. "Beyond CASSI" lists abbreviated journal titles from early chemical literature and other historical reference sources. "Chemical Abstracts" ("C... | https://en.wikipedia.org/wiki?curid=585185 |
Chemical Abstracts Service Baker became the CAS Director upon Crane's retirement in 1958. According to CAS, his visionary view of CAS' potential "led to expansion, modernization, and the forging of international alliances with other information organizations." CAS was an early leader in the use of computer technology t... | https://en.wikipedia.org/wiki?curid=585185 |
Penning trap A is a device for the storage of charged particles using a homogeneous axial magnetic field and an inhomogeneous quadrupole electric field. This kind of trap is particularly well suited to precision measurements of properties of ions and stable subatomic particles. Geonium atoms have been created and studi... | https://en.wikipedia.org/wiki?curid=586599 |
Penning trap Pierce's 1949 book, and I developed a simple description of the axial, magnetron, and cyclotron motions of an electron in it. With the help of the expert glassblower of the Department, Jake Jonson, I built my first high vacuum magnetron trap in 1959 and was soon able to trap electrons for about 10 sec and ... | https://en.wikipedia.org/wiki?curid=586599 |
Penning trap These motions are similar to the deferent and epicycle, respectively, of the Ptolemaic model of the solar system. The sum of these two frequencies is the "cyclotron" frequency, which depends only on the ratio of electric charge to mass and on the strength of the magnetic field. This frequency can be measur... | https://en.wikipedia.org/wiki?curid=586599 |
Penning trap Firstly, in the only static fields are applied and therefore there is no micro-motion and resultant heating of the ions due to the dynamic fields, even for extended 2- and 3-dimensional ion Coulomb crystals. Also, the can be made larger whilst maintaining strong trapping. The trapped ion can then be held f... | https://en.wikipedia.org/wiki?curid=586599 |
Penning trap For this the ring electrode is segmented and opposite electrodes are connected to a superconducting coil and the source and the gate of a field-effect transistor. The coil and the parasitic capacitances of the circuit form a LC circuit with a Q of about 50 000. The LC circuit is excited by an external elec... | https://en.wikipedia.org/wiki?curid=586599 |
Penning trap Energy levels and g-factor of the particle can be measured with high precision. Van Dyck, Jr et al. explored the magnetic splitting of geonium spectra in 1978 and in 1987 published high-precision measurements of electron and positron g-factors, which constrained the electron radius. In November 2017, an in... | https://en.wikipedia.org/wiki?curid=586599 |
Wastewater treatment is a process used to remove contaminants from wastewater or sewage and convert it into an effluent that can be returned to the water cycle with minimum impact on the environment, or directly reused. The latter is called water reclamation because treated wastewater can be used for other purposes. Th... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment International treaties may also regulate disposal into rivers crossing international borders. Water bodies entirely within the jurisdiction of a single nation may be subject to regulations of multiple local governments. Acceptable impurity concentrations may vary widely among different jurisdiction... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment Disposal options for dried solids vary with the type and concentration of impurities removed from water. Production of waste brine, however, may discourage wastewater treatment removing dissolved inorganic solids from water by methods like ion exchange, reverse osmosis, and distillation. Solids lik... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment Secondary treatment converts organic compounds into carbon dioxide, water, and biosolids. Chemical oxidation is widely used for disinfection. Secondary treatment by biochemical oxidation of dissolved and colloidal organic compounds is widely used in sewage treatment and is applicable to some agricu... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment whether it is sewage, industrial wastewater, agricultural wastewater or leachate. A typical municipal sewage treatment plant in an industrialized country may include primary treatment to remove solid material, secondary treatment to digest dissolved and suspended organic material as well as the nut... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment The latest, and very promising treatment technology is the use aerobic granulation. Disposal of wastewaters from an industrial plant is a difficult and costly problem. Most petroleum refineries, chemical and petrochemical plants have onsite facilities to treat their wastewaters so that the pollutan... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment Although economies of scale may favor use of a large municipal sewage treatment plant for disposal of small volumes of industrial wastewater, industrial wastewater treatment and disposal may be less expensive than correctly apportioned costs for larger volumes of industrial wastewater not requiring... | https://en.wikipedia.org/wiki?curid=588004 |
Wastewater treatment Point sources must obtain surface water discharge permits through the National Pollutant Discharge Elimination System (NPDES). Point sources include industrial facilities, municipal governments (sewage treatment plants and storm sewer systems), other government facilities such as military bases, an... | https://en.wikipedia.org/wiki?curid=588004 |
Bimetallic strip A bimetallic strip is used to convert a temperature change into mechanical displacement. The strip consists of two strips of different metals which expand at different rates as they are heated, usually steel and copper, or in some cases steel and brass. The different expansions force the flat strip to ... | https://en.wikipedia.org/wiki?curid=589225 |
Bimetallic strip The sideways displacement of the strip is much larger than the small lengthways expansion in either of the two metals. In some applications the bimetal strip is used in the flat form. In others, it is wrapped into a coil for compactness. The greater length of the coiled version gives improved sensitivi... | https://en.wikipedia.org/wiki?curid=589225 |
Bimetallic strip Harrison's invention is recognized in the memorial to him in Westminster Abbey, England. This effect is used in a range of mechanical and electrical devices. Mechanical clock mechanisms are sensitive to temperature changes as each part has tiny tolerance and it leads to errors in time keeping. A bimeta... | https://en.wikipedia.org/wiki?curid=589225 |
Bimetallic strip Some thermostats use a mercury switch connected to both electrical leads. The angle of the entire mechanism is adjustable to control the set point of the thermostat. Depending upon the application, a higher temperature may open a contact (as in a heater control) or it may close a contact (as in a refri... | https://en.wikipedia.org/wiki?curid=589225 |
Bimetallic strip A bimetallic strip is also used in a recording thermometer. Breguet's thermometer consists of a tri-metallic helix in order to have a more accurate result. Heat engines are not the most efficient ones, and with the use of bimetallic strips the efficiency of the heat engines is even lower as there is no... | https://en.wikipedia.org/wiki?curid=589225 |
Pi bond In chemistry, pi bonds (π bonds) are covalent chemical bonds where two lobes of an orbital on one atom overlap two lobes of an orbital on another atom and this overlap occurs laterally. Each of these atomic orbitals has zero electron density at a shared nodal plane, passing through the two bonded nuclei. The sa... | https://en.wikipedia.org/wiki?curid=589286 |
Pi bond Pi bonds are more diffuse bonds than the sigma bonds. Electrons in pi bonds are sometimes referred to as pi electrons. Molecular fragments joined by a pi bond cannot rotate about that bond without breaking the pi bond, because rotation involves destroying the parallel orientation of the constituent p orbitals. ... | https://en.wikipedia.org/wiki?curid=589286 |
Pi bond For example, in organic chemistry, carbon–carbon bond lengths are about 154 pm in ethane, 134 pm in ethylene and 120 pm in acetylene. More bonds make the total bond shorter and stronger. A pi bond can exist between two atoms that do not have a net sigma-bonding effect between them. In certain metal complexes, p... | https://en.wikipedia.org/wiki?curid=589286 |
Molecular orbital theory In chemistry, Molecular orbital (MO) theory is a method for describing the electronic structure of molecules using quantum mechanics. Electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of the nuclei in the whole molecule. The spatial and ... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory A larger coefficient means that the orbital basis is composed more of that particular contributing atomic orbital—hence, the molecular orbital is best characterized by that type. This method of quantifying orbital contribution as a linear combination of atomic orbitals is used in computational ... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory According to physicist and physical chemist Erich Hückel, the first quantitative use of molecular orbital theory was the 1929 paper of Lennard-Jones. This paper predicted a triplet ground state for the dioxygen molecule which explained its paramagnetism (see ) before valence bond theory, which ... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory This rigorous approach is known as the Hartree–Fock method for molecules although it had its origins in calculations on atoms. In calculations on molecules, the molecular orbitals are expanded in terms of an atomic orbital basis set, leading to the Roothaan equations. This led to the developmen... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory Electrons in non-bonding orbitals tend to be associated with atomic orbitals that do not interact positively or negatively with one another, and electrons in these orbitals neither contribute to nor detract from bond strength. Molecular orbitals are further divided according to the types of ato... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory For instance, in the simple case of a hydrogen diatomic molecule, promotion of a single electron from a bonding orbital to an antibonding orbital can occur under UV radiation. This promotion weakens the bond between the two hydrogen atoms and can lead to photodissociation—the breaking of a chem... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory In this molecule, 24 of the 30 total valence bonding electrons—24 coming from carbon atoms and 6 coming from hydrogen atoms—are located in 12 σ (sigma) bonding orbitals, which are located mostly between pairs of atoms (C-C or C-H), similarly to the electrons in the valence bond description. How... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory When methane is ionized, a single electron is taken from the valence MOs, which can come from the s bonding or the triply degenerate p bonding levels, yielding two ionization energies. In comparison, the explanation in VB theory is more complicated. When one electron is removed from an sp orbit... | https://en.wikipedia.org/wiki?curid=589303 |
Molecular orbital theory MO theory recognizes that some electrons in the graphite atomic sheets are completely delocalized over arbitrary distances, and reside in very large molecular orbitals that cover an entire graphite sheet, and some electrons are thus as free to move and therefore conduct electricity in the sheet... | https://en.wikipedia.org/wiki?curid=589303 |
Perxenate In chemistry, perxenates are salts of the yellow xenon-containing anion . This anion has octahedral molecular geometry, as determined by Raman spectroscopy, having O–Xe–O bond angles varying between 87° and 93°. The Xe–O bond length was determined by X-ray crystallography to be 1.875 Å. Perxenates are synthes... | https://en.wikipedia.org/wiki?curid=589488 |
Perxenate The sodium, potassium, and barium salts are soluble. Barium perxenate solution is used as the starting material for the synthesis of xenon tetroxide (XeO) by mixing it with concentrated sulfuric acid: Most metal perxenates are stable, except silver perxenate, which decomposes violently. Sodium perxenate, NaXe... | https://en.wikipedia.org/wiki?curid=589488 |
Xenon tetroxide is a chemical compound of xenon and oxygen with molecular formula XeO, remarkable for being a relatively stable compound of a noble gas. It is a yellow crystalline solid that is stable below −35.9 °C (-33 F°); above that temperature it is very prone to exploding and decomposing into elemental xenon and ... | https://en.wikipedia.org/wiki?curid=589503 |
Xenon tetroxide One is the disproportionation of xenates to perxenates and xenon: The other is oxidation of the xenates with ozone in basic solution: Barium perxenate is reacted with sulfuric acid and the unstable perxenic acid is dehydrated to give xenon tetroxide: Any excess perxenic acid slowly undergoes a decomposi... | https://en.wikipedia.org/wiki?curid=589503 |
Corrin is a heterocyclic compound. It is the parent macrocycle related to the substituted derivative that is found in vitamin B. Its name reflects that it is the "core" of vitamin B (cobalamins). Upon deprotonation, the corrinoid ring is capable of binding cobalt. In vitamin B, the resulting complex also features a ben... | https://en.wikipedia.org/wiki?curid=182455 |
Porphyrin Porphyrins ( ) are a group of heterocyclic macrocycle organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (=CH−). The parent of porphyrin is porphine, a rare chemical compound of exclusively theoretical interest. Substituted porphines are ca... | https://en.wikipedia.org/wiki?curid=182499 |
Porphyrin verteporfin is a benzoporphyrin derivative. Several other heterocycles are related to porphyrins. These include corrins, chlorins, bacteriochlorophylls, and corphins. Chlorins (2,3-dihydroporphyrin) are more reduced, contain more hydrogen than porphyrins, i.e. one pyrrole has been converted to a pyrroline. Th... | https://en.wikipedia.org/wiki?curid=182499 |
Porphyrin The enzymes involved in this pathway are glutamyl-tRNA synthetase, glutamyl-tRNA reductase, and glutamate-1-semialdehyde 2,1-aminomutase. This pathway is known as the C5 or Beale pathway. Two molecules of dALA are then combined by porphobilinogen synthase to give porphobilinogen (PBG), which contains a pyrrol... | https://en.wikipedia.org/wiki?curid=182499 |
Porphyrin In solution-phase synthesis, acidic conditions are essential; formic acid, acetic acid, and propionic acid are typical reaction solvents, or "p"-toluenesulfonic acid or various Lewis acids can be used with a non-acidic solvent. A large amount of side-product is formed and is removed, usually by recrystallizat... | https://en.wikipedia.org/wiki?curid=182499 |
Porphyrin Bacteria have been shown to produce porphyrins endogenously as byproducts in heme biosynthesis, and these can be used in phototherapy to treat bacterial infections, such as acne. The field of organic geochemistry, the study of the impacts and processes that organisms have had on the Earth, had its origins in ... | https://en.wikipedia.org/wiki?curid=182499 |
Porphyrin Metalloporphyrins are also studied as catalysts for water splitting, with the purpose of generating molecular hydrogen and oxygen for fuel cells. Porphyrin-based compounds are of interest as possible components of molecular electronics and photonics. Synthetic porphyrin dyes have been incorporated in prototyp... | https://en.wikipedia.org/wiki?curid=182499 |
Winkler test for dissolved oxygen The Winkler test is used to determine the concentration of dissolved oxygen in water samples. Dissolved oxygen (D.O.) is widely used in water quality studies and routine operation of water reclamation facilities to analyze its level of oxygen saturation. In the test, an excess of manga... | https://en.wikipedia.org/wiki?curid=182650 |
Winkler test for dissolved oxygen Phytoplankton and macroalgae present in the water mass-produce oxygen by way of photosynthesis. Bacteria and eukaryotic organisms (zooplankton,fish) consume this oxygen through cellular respiration. The result of these two mechanisms determines the concentration of dissolved oxygen, wh... | https://en.wikipedia.org/wiki?curid=182650 |
Winkler test for dissolved oxygen The acid facilitates the conversion by the brown, Manganese-containing precipitate of the Iodide ion into elemental Iodine. The Mn(SO) formed by the acid converts the iodide ions into iodine, itself being reduced back to manganese(II) ions in an acidic medium. Thiosulfate is used, with... | https://en.wikipedia.org/wiki?curid=182650 |
Winkler test for dissolved oxygen The difference in DO and the dilution factor are used to calculated BOD. The resulting number (usually reported in parts per million or milligrams per liter) is useful in determining the relative organic strength of sewage or other polluted waters. The BOD test is an example of analysi... | https://en.wikipedia.org/wiki?curid=182650 |
Chlorin In organic chemistry, a chlorin is a tetrapyrrole. Chlorins are partially hydrogenated versions of porphyrins. The parent chlorin is a rare compound, but substituted chlorins are common. Magnesium-containing chlorins are called chlorophylls. Chlorophylls are the photosensitive pigment in chloroplasts. Related t... | https://en.wikipedia.org/wiki?curid=182695 |
Magnetohydrodynamic drive A magnetohydrodynamic drive or MHD accelerator is a method for propelling vehicles using only electric and magnetic fields with no moving parts, accelerating an electrically conductive propellant (liquid or gas) with magnetohydrodynamics. The fluid is directed to the rear and as a reaction, th... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive The working principle involves the acceleration of an electrically conductive fluid (which can be a liquid or an ionized gas called a plasma) by the Lorentz force, resulting from the cross product of an electric current (motion of charge carriers accelerated by an electric field applied betwee... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive As the Lorentz force in an MHD converter does not act on a single isolated charged particle nor on electrons in a solid electrical wire, but on a continuous charge distribution in motion, it is a "volumetric" (body) force, a force per unit volume: where f is the "force density" (force per unit... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive Additionally, the MHD design eliminates many of the wear and friction pieces of the drivetrain with a directly driven propeller by an engine. Problems with current technologies include expense and slow speed compared to a propeller driven by an engine. The extra expense is from the large gener... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive Small-scale ship models were later built and studied extensively in the laboratory, leading to successful comparisons between the measurements and the theoretical prediction of ship terminal speeds. Military research about underwater MHD propulsion included high-speed torpedoes, remotely opera... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive Active flow control by MHD force fields on the contrary involves a direct and imperious action of forces to locally accelerate or slow down the airflow, modifying its velocity, direction, pressure, friction, heat flux parameters, in order to preserve materials and engines from stress, allowing... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive These projects aim to develop MHD generators feeding MHD accelerators for a new generation of high-speed vehicles. Such MHD bypass systems are often designed around a scramjet engine, but easier to design turbojets are also considered, as well as subsonic ramjets. Such studies covers a field o... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive As external flow systems can control the flow over the whole wetted area, limiting thermal issues at high speeds, ambient air would be ionized and radially accelerated by Lorentz forces around an axisymmetric body (shaped as a cylinder, a cone, a sphere…), the entire airframe being the engine.... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive As this kind of MHD propulsion involves compressible fluids in the form of plasmas (ionized gases) it is also referred to as magnetogasdynamics or magnetoplasmadynamics. In such electromagnetic thrusters, the working fluid is most of the time ionized hydrazine, xenon or lithium. Depending on t... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive Even today, these systems are not ready to be launched in space as they still lack a suitable compact power source offering enough energy density (such as hypothetical fusion reactors) to feed the power-greedy electromagnets, especially pulsed inductive ones. The rapid ablation of electrodes u... | https://en.wikipedia.org/wiki?curid=182734 |
Magnetohydrodynamic drive In the Ben Bova novel "The Precipice," the ship where some of the action took place, "Starpower 1," built to prove that exploration and mining of the Asteroid Belt was feasible and potentially profitable, had a magnetohydrodynamic drive mated to a fusion power plant. | https://en.wikipedia.org/wiki?curid=182734 |
Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine substances from liquids or air. It is used in science labs to remove solids from liquids. This can be used to remove sand from water. has various properties. The important parameters are wet strength... | https://en.wikipedia.org/wiki?curid=182839 |
Filter paper Normally particularly long fibrous pulp that is mercerised is used to get these properties. The paper is normally impregnated to improve the resistance to moisture. Some heavy duty qualities are made to be rinsed and thereby extend the life of the filter. Coffee filters of paper are made from about 100 g/m... | https://en.wikipedia.org/wiki?curid=182839 |
Filter paper There are total 13 different grades of qualitative filter paper. The largest pore size is grade 4; the smallest pore size is grade 602 h; the most commonly used grades are grade 1 to grade 4. Grade 1 qualitative filter paper has the pore size of 11 μm. This grade of filter paper is widely used for many dif... | https://en.wikipedia.org/wiki?curid=182839 |
Filter paper Chromatography is a method chemists use to separate compounds. This type of filter paper has specific water flow rate and absorption speed to maximize the result of paper chromatography. The absorption speed of this type of filter paper is from 6 cm to 18 cm and the thickness is from 0.17 mm from 0.93 mm. ... | https://en.wikipedia.org/wiki?curid=182839 |
Filter paper Engine oil is filtered to remove impurities. Filtration of oil is normally done with volume filtration. Filter papers for lubrication oils are impregnated to resist high temperatures. Tea bags are made from abacá fibers, a very thin and long fiber manilla hemp. Often the paper is augmented with a minor por... | https://en.wikipedia.org/wiki?curid=182839 |
Nernst heat theorem The was formulated by Walther Nernst early in the twentieth century and was used in the development of the third law of thermodynamics. The says that as absolute zero is approached, the entropy change ΔS for a chemical or physical transformation approaches 0. This can be expressed mathematically as ... | https://en.wikipedia.org/wiki?curid=182842 |
Connate fluids In geology and sedimentology, connate fluids are liquids that were trapped in the pores of sedimentary rocks as they were deposited. These liquids are largely composed of water, but also contain many mineral components as ions in solution. As rocks are buried, they undergo lithification and the connate f... | https://en.wikipedia.org/wiki?curid=183132 |
Connate fluids , the last ice age) so is also very old, but possibly not of the same genesis as the rock. | https://en.wikipedia.org/wiki?curid=183132 |
Submitochondrial particle A submitochondrial particle is a compartmentalized membranous product of exposing mitochondria to ultrasound. This causes the cristae to pinch off, forcing the inner mitochondrial membrane inside out. As a consequence, the F particle becomes exposed and on the outside. Using chaotropic agents ... | https://en.wikipedia.org/wiki?curid=183222 |
Exploratory engineering is a term coined by K. Eric Drexler to describe the process of designing and analyzing detailed hypothetical models of systems that are not feasible with current technologies or methods, but do seem to be clearly within the bounds of what science considers to be possible within the narrowly defi... | https://en.wikipedia.org/wiki?curid=183275 |
Exploratory engineering often posits that a highly detailed solution exists, and explores the putative characteristics of such a solution, while holding in abeyance the question of how to implement that solution. If a point can be reached where the attempted implementation of the solution is addressed using the princip... | https://en.wikipedia.org/wiki?curid=183275 |
Exploratory engineering While both critics and proponents often agree that much of the highly detailed simulation effort in the field may never result in a physical device, the dichotomy between the two groups is exemplified by the situation in which proponents of molecular nanotechnology contend that many complicated ... | https://en.wikipedia.org/wiki?curid=183275 |
Exploratory engineering On the negative side of the same ledger, other science fiction devices such as the space elevator may be forever impossible because of basic strength of materials issues or due to other difficulties, either anticipated or unanticipated. 2. Eric Drexler : "Physical Laws and the future of nanotech... | https://en.wikipedia.org/wiki?curid=183275 |
Life extension is the idea of extending the human lifespan, either modestly – through improvements in medicine – or dramatically by increasing the maximum lifespan beyond its generally settled limit of 125 years. The ability to achieve such dramatic changes, however, does not currently exist. Some researchers in this a... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension Specifically, aging is characterized as and thought to be caused by "genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication." Oxidati... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension Widely recognized methods of extending maximum lifespan in model organisms such as nematodes, fruit flies, and mice include caloric restriction, gene manipulation, and administration of pharmaceuticals. Another technique uses evolutionary pressures such as breeding from only older members or altering lev... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension For example, the American Medical Association has been critical of some anti-aging hormone therapies. While growth hormone (GH) decreases with age, the evidence for use of growth hormone as an anti-aging therapy is mixed and based mostly on animal studies. There are mixed reports that GH or IGF-1 modulat... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension Among the foremost researchers of life extension at this period were the Nobel Prize winning biologist Elie Metchnikoff (1845-1916) -- the author of the cell theory of immunity and vice director of Institut Pasteur in Paris, and Charles-Édouard Brown-Séquard (1817-1894) -- the president of the French Bio... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension After 11 years of legal battles, Kent and Faloon convinced the US Attorney’s Office to dismiss all criminal indictments brought against them by the FDA. In 2003, Doubleday published "The Immortal Cell: One Scientist's Quest to Solve the Mystery of Human Aging," by Michael D. West. West emphasised the pot... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension In 2013, Google announced Calico, a new company based in San Francisco that will harness new technologies to increase scientific understanding of the biology of aging. It is led by Arthur D. Levinson, and its research team includes scientists such as Hal V. Barron, David Botstein, and Cynthia Kenyon. In ... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension The research shows that when consumers pursue a hoped-for self, it is expectations of success that most strongly drive their motivation to use the product. The research also shows why doing badly when trying to avoid a feared self is more motivating than doing well. When product use is seen to fail it is... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension He states his opposition to life extension with the words: John Harris, former editor-in-chief of the Journal of Medical Ethics, argues that as long as life is worth living, according to the person himself, we have a powerful moral imperative to save the life and thus to develop and offer life extension ... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension A Spring 2013 Pew Research poll in the United States found that 38% of Americans would want life extension treatments, and 56% would reject it. However, it also found that 68% believed most people would want it and that only 4% consider an "ideal lifespan" to be more than 120 years. The median "ideal lif... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension David Gems, assistant director of the Institute of Healthy Ageing, argues that aging should be viewed as a disease. In response to the universality of aging, David Gems notes that it is as misleading as arguing that Basenji are not dogs because they do not bark. Because of the universality of aging he ca... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension Since 2009, investigators have found ways to increase the lifespan of nematode worms and yeast by 10-fold; the record in nematodes was achieved through genetic engineering and the extension in yeast by a combination of genetic engineering and caloric restriction. A 2009 review of longevity research noted... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension Based on that research, there have been attempts to develop drugs that will have the same effect on the aging process as a caloric restriction diet, which are known as Caloric restriction mimetic drugs. Some drugs that are already approved for other uses have been studied for possible longevity effects o... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension According to Richard Feynman, it was his former graduate student and collaborator Albert Hibbs who originally suggested to him (circa 1959) the idea of a "medical" use for Feynman's theoretical nanomachines (see biological machine). Hibbs suggested that certain repair machines might one day be reduced in... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension The use of human stem cells, particularly embryonic stem cells, is controversial. Opponents' objections generally are based on interpretations of religious teachings or ethical considerations. Proponents of stem cell research point out that cells are routinely formed and destroyed in a variety of context... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension While many biogerontologists find these ideas "worthy of discussion" and SENS conferences feature important research in the field, some contend that the alleged benefits are too speculative given the current state of technology, referring to it as "fantasy rather than science". Genome editing, in which n... | https://en.wikipedia.org/wiki?curid=183290 |
Life extension Therefore, to extend life, we should be able to prevent these genes from switching on, and we should be able to do so by "identifying changes in the internal chemical environment of a body that take place during aging... and by simulating the superficial chemical properties of a young body". One hypothet... | https://en.wikipedia.org/wiki?curid=183290 |
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