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Topic Review
Shear Strain
In physics, deformation is the continuum mechanics transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body. A deformation can occur because of external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. Strain is related to deformation in terms of relative displacement of particles in the body that excludes rigid-body motions. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor or its dual is considered. In a continuous body, a deformation field results from a stress field due to applied forces or because of some changes in the temperature field of the body. The relation between stress and strain is expressed by constitutive equations, e.g., Hooke's law for linear elastic materials. Deformations which cease to exist after the stress field is removed are termed as elastic deformation. In this case, the continuum completely recovers its original configuration. On the other hand, irreversible deformations remain. They exist even after stresses have been removed. One type of irreversible deformation is plastic deformation, which occurs in material bodies after stresses have attained a certain threshold value known as the elastic limit or yield stress, and are the result of slip, or dislocation mechanisms at the atomic level. Another type of irreversible deformation is viscous deformation, which is the irreversible part of viscoelastic deformation. In the case of elastic deformations, the response function linking strain to the deforming stress is the compliance tensor of the material.
  • 5.0K
  • 11 Nov 2022
Topic Review
Composition of Barley
Barley (Hordeum vulgare L.) is one such feed ingredient, the use of which remains limited in poultry diets due to its low metabolisable energy, presence of anti-nutritive, soluble non-starch polysaccharides and consequent inter-cultivar variability. 
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  • 01 Nov 2022
Topic Review
Cincinnati Radiation Experiments (1960-1971)
The Cincinnati Radiation Experiments were a series of total and partial body irradiation tests performed on at least 90 patients with advanced cancer at the Cincinnati General Hospital, now University Hospital, from 1960-1971. Led by radiologist Dr. Eugene L. Saenger, the experiments were funded in part by the Defense Atomic Support Agency within the Department of Defense to study how soldiers in nuclear war would be affected by large doses of radiation. The experiments were conducted without patient consent in the first five years of the study and with disputed levels of consent thereafter. The irradiated patients experienced nausea, vomiting, cognitive impairment, and death. The contract between the researchers and the DOD terminated in 1972 under pressure from Senator Edward Kennedy, marking the end of major human irradiation experimentation in the U.S. that began after World War II and continued throughout the Cold War Era. Although initially fading from public eye, the controversy resurfaced in 1993 and was soon investigated by President Bill Clinton’s Advisory Committee on Human Radiation Experiments. In 1994, families of the patients filed a class-action lawsuit against the team of 15 researchers. Five years later, the University of Cincinnati settled the case for over $4 million.
  • 5.0K
  • 20 Oct 2022
Topic Review
Primal Therapy
Primal therapy is a trauma-based psychotherapy created by Arthur Janov, who argues that neurosis is caused by the repressed pain of childhood trauma. Janov argues that repressed pain can be sequentially brought to conscious awareness and resolved through re-experiencing specific incidents and fully expressing the resulting pain during therapy. In therapy, the patient recalls and reenacts a particularly disturbing past experience usually occurring early in life and expresses normally repressed anger or frustration especially through spontaneous and unrestrained screams, hysteria, or violence. Primal therapy was developed as a means of eliciting the repressed pain; the term Pain is capitalized in discussions of primal therapy when referring to any repressed emotional distress and its purported long-lasting psychological effects. Janov criticizes the talking therapies as they deal primarily with the cerebral cortex and higher-reasoning areas and do not access the source of Pain within the more basic parts of the central nervous system. Primal therapy is used to re-experience childhood pain—i.e., felt rather than conceptual memories—in an attempt to resolve the pain through complete processing and integration, becoming real. An intended objective of the therapy is to lessen or eliminate the hold early trauma exerts on adult behaviour. Primal therapy became very influential during a brief period in the early 1970s, after the publication of Janov's first book, The Primal Scream. It inspired hundreds of spin-off clinics worldwide and served as an inspiration for many popular cultural icons. Singer-songwriter John Lennon, actor James Earl Jones, and pianist Roger Williams were prominent advocates of primal therapy. Primal therapy has since declined in popularity, partly because Janov had not demonstrated in research the outcomes necessary to convince research-oriented psychotherapists of its effectiveness. Proponents of the methodology continue to advocate and practice the therapy or variations of it.
  • 5.0K
  • 23 Nov 2022
Topic Review
Gene Therapy
Gene therapy is an experimental technique that uses genes to treat or prevent disease. 
  • 5.0K
  • 24 Dec 2020
Topic Review
Dog-Whistle Politics
Dog-whistle politics is the use of coded or suggestive language in politics to garner support from a wider audience for a candidate. Dog whistles serve the purpose of attracting the intended political audience without garnering ire with opposing audiences, similar to ultrasonic dog whistles used in sheepherding. The concept of dog-whistles has similarities to the concept of code words. Accusations of dog-whistling may be used to accuse an individual of expressing a "hidden" meaning when no such message was intended and the actual words used are innocuous. Such accusations can be a form of political correctness or gaslighting and are by their nature impossible to refute. An example is the accusation that using the phrase "international banks" is evidence of anti-Semitism. When it exists, a dog-whistle is a type of doublespeak used in political messaging. Dog whistles work by employing language that has normal meanings to the majority, but can be implied or loaded to mean very specific things to intended recipients. One example commonly believed to be dog whistling may include is the use of 'family values' as a signal to Christians that the candidate is Christian and would support policies related to Christian values without raising flags among the non-religious who might oppose a Christian candidate. This type of dog whistle would serve the purpose of gaining popularity with Christians without losing popularity with non-Christians.
  • 5.0K
  • 25 Nov 2022
Topic Review
Synthetic Applications of Lawesson’s Reagent in Organic Synthesis
Lawesson’s reagent (LR) is a well-known classic example of a compound with unique construction and unusual chemical behavior, with a wide range of applications in synthetic organic chemistry. Its main functions were rounded for the thionation of various carbonyl groups in the early days. Now its use can help the chemistry community to understand innovative ideas. These include constructing biologically valuable heterocycles, coupling reactions, and the thionation of natural compounds.
  • 5.0K
  • 27 Nov 2021
Topic Review
Bessel Beam
Diffraction is a phenomenon related to the wave nature of light and arises when a propagating wave comes across an obstacle. Consequently, the wave can be transformed in amplitude or phase and diffraction occurs. Those parts of the wavefront avoiding an obstacle form a diffraction pattern after interfering with each other. In this review paper, we have discussed the topic of non-diffractive beams, explicitly Bessel beams. Such beams provide some resistance to diffraction and hence are hypothetically a phenomenal alternate to Gaussian beams in several circumstances. Several outstanding applications are coined to Bessel beams and have been employed in commercial applications. We have discussed several hot applications based on these magnificent beams such as optical trapping, material processing, free-space long-distance self-healing beams, optical coherence tomography, superresolution, sharp focusing, polarization transformation, increased depth of focus, birefringence detection based on astigmatic transformed BB and encryption in optical communication. According to our knowledge, each topic presented in this entry is justifiably explained.
  • 5.0K
  • 09 Dec 2020
Topic Review
Vanillin Production from Lignin
Vanillin, one of the most widely used and appreciated flavoring agents worldwide, is the main constituent of vanilla bean extract, obtained from the seed pods of various members belonging to the Orchidaceae family. Due to the great demand in the food confectionery industry, as well as in the perfume industry, medicine, and more, the majority of vanillin used today is produced synthetically, and only less than one percent of the world’s vanilla flavoring market comes directly from the traditional natural sources. The increasing global demand for vanillin requires alternative and overall sustainable new production methods, and the recovery from biobased polymers, like lignin, is an environmentally friendly alternative to chemical synthesis. 
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  • 01 Feb 2024
Topic Review
Objectivity
In philosophy, objectivity is the concept of truth independent from individual subjectivity (bias caused by one's perception, emotions, or imagination). A proposition is considered to have objective truth when its truth conditions are met without bias caused by the mind of a sentient being. Scientific objectivity refers to the ability to judge without partiality or external influence. Objectivity in the moral framework calls for moral codes to be assessed based on the well-being of the people in the society that follow it. Moral objectivity also calls for moral codes to be compared to one another through a set of universal facts and not through subjectivity.
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  • 03 Nov 2022
Topic Review
N-Acetylcysteine
Exercise frequently alters the metabolic processes of oxidative metabolism in athletes, including exposure to extreme reactive oxygen species impairing exercise performance. Therefore, both researchers and athletes have been consistently investigating the possible strategies to improve metabolic adaptations to exercise-induced oxidative stress. N-acetylcysteine (NAC) has been applied as a therapeutic agent in treating many diseases in humans due to its precursory role in the production of hepatic glutathione, a natural antioxidant.
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  • 03 Feb 2021
Topic Review
The Hero with a Thousand Faces
The Hero with a Thousand Faces (first published in 1949) is a work of comparative mythology by Joseph Campbell. In this book, Campbell discusses his theory of the mythological structure of the journey of the archetypal hero found in world myths. Since the publication of The Hero with a Thousand Faces, Campbell's theory has been consciously applied by a wide variety of modern writers and artists. Filmmaker George Lucas acknowledged Campbell's theory in mythology, and its influence on the Star Wars films. The Joseph Campbell Foundation and New World Library issued a new edition of The Hero with a Thousand Faces in July 2008 as part of the Collected Works of Joseph Campbell series of books, audio and video recordings. In 2011, Time (magazine) placed the book in its list of the 100 best and most influential books written in English since the magazine was founded in 1923.
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  • 20 Oct 2022
Topic Review
Space Travel Using Constant Acceleration
Constant acceleration is a proposed aspect of most future forms of space travel. It entails that the propulsion system of whatever kind operate continuously with a steady acceleration, rather than the brief impulsive thrusts used by chemical rockets — for the first half of the journey it constantly pushes the spacecraft towards its destination, and for the last half of the journey it constantly uses backthrust, so that the spaceship arrives at the destination at a standstill.
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  • 11 Oct 2022
Topic Review
Pyrolysis and Gasification Mechanism of Biomass
Biomass can be converted to energy by using thermochemical and biochemical methodsecology; environmental; biomass; pyrolysis. Biochemical methods, including anaerobic digestion and fermentation, constitute the transformation of cellulose and hemicellulose into biofuel at the stages of hydrolysis and fermentation. At present, biochemical methods are cost-intensive, and involve problems with using lignin-rich biomass.
  • 5.0K
  • 26 Nov 2021
Topic Review
Ascorbic Acid-Induced Reactions
Ascorbic acid is the most well-known vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis. Ascorbic acid can be used as a substrate or mediator in organic synthesis. In this review, we report ascorbic acid-catalyzed reactions in organic synthesis. Several examples are included in this review to demonstrate that ascorbic acid is a versatile catalyst for the synthesis of diverse organic compounds. Reactions catalyzed by ascorbic acid are performed in organic or aqueous media. The readily available and easy handling features of ascorbic acid make these procedures highly fascinating.
  • 5.0K
  • 25 Nov 2020
Topic Review
Physical Body
In physics, a physical body or physical object (or simply a body or object) is an identifiable collection of matter, which may be constrained by an identifiable boundary, and may move as a unit by translation or rotation, in 3-dimensional space. In common usage, an object is a collection of matter within a defined contiguous boundary in 3-dimensional space. The boundary must be defined and identified by the properties of the material. The boundary may change over time. The boundary is usually the visible or tangible surface of the object. The matter in the object is constrained (to a greater or lesser degree) to move as one object. The boundary may move in space relative to other objects that it is not attached to (through translation and rotation). An object's boundary may also deform and change over time in other ways. Also in common usage, an object is not constrained to consist of the same collection of matter. Atoms or parts of an object may change over time. An object is defined by the simplest representation of the boundary consistent with the observations. However the laws of Physics only apply directly to objects that consist of the same collection of matter. Each object has a unique identity, independent of any other properties. Two objects may be identical, in all properties except position, but still remain distinguishable. In most cases the boundaries of two objects may not overlap at any point in time. The property of identity allows objects to be counted. Examples of models of physical bodies include, but are not limited to a particle, several interacting smaller bodies (particles or other), and continuous media. The common conception of physical objects includes that they have extension in the physical world, although there do exist theories of quantum physics and cosmology which may challenge this. In modern physics, "extension" is understood in terms of the spacetime: roughly speaking, it means that for a given moment of time the body has some location in the space, although not necessarily a point. A physical body as a whole is assumed to have such quantitative properties as mass, momentum, electric charge, other conserving quantities, and possibly other quantities. A body with known composition and described in an adequate physical theory is an example of physical system.
  • 5.0K
  • 12 Dec 2022
Topic Review
TCV and TGV Technology
Through ceramic via (TCV) technology expands the volume of high-precision and high-power thin-film circuits with 3D planar distribution, significantly improves the structural density and reduces the device size through via interconnection and circuit redistribution. Through glass via (TGV) technology has the advantages of high-density interconnection and low-loss transmission, which forms a highly reliable interconnection between the chip and the substrate, has higher I/O density and smaller spacing, and realizes passive on-chip devices, high-density copper interconnection and the heterogeneous integration of chips. Therefore, 3D integration and system-level packaging technology have developed rapidly.
  • 5.0K
  • 26 Jul 2023
Topic Review
Cheese By-Products
Cheese whey (CW) is nowadays recognized as a source of functional and bioactive compounds, especially proteins and peptides. However, a large proportion of the whey produced worldwide is still not valorized. This results from the fact that small and medium size dairy industries lack dimension to make the necessary investments for CW valorization. In some countries such as Portugal, Spain, Italy and Turkey, CW is employed in the production of whey cheeses. The liquid remaining after whey cheese production represents more than 90% of the original whey and is called second cheese whey (SCW). SCW is a poorly studied by-product and there is little interest in its recovery. SCW is a poorly studied by-product and there is little interest in its recovery. Some authors studied the use of SCW for conversion into biofuel and as a biotechnological substrate for fermented products while others studied its potential for the production of fermented drinks. However, half of CW and almost all SCW are not valorized for human consumption. This review presents several alternatives for the valorization of both by-products.
  • 5.0K
  • 20 May 2021
Topic Review
Electronic Trading
Electronic or scripless trading, sometimes called e-trading or paperless trading is a method of trading securities (such as stocks, and bonds), foreign exchange or financial derivatives electronically. Information technology is used to bring together buyers and sellers through an electronic trading platform and network to create virtual market places. They can include various exchange-based systems, such as NASDAQ, NYSE Arca and Globex, as well as other types of trading platforms, such as electronic communication networks (ECNs), alternative trading systems, crossing networks and "dark pools". Electronic trading is rapidly replacing human trading in global securities markets. Electronic trading is in contrast to older floor trading and phone trading and has a number of advantages, but glitches and cancelled trades do still occur.
  • 5.0K
  • 14 Oct 2022
Topic Review
Purple Non-Sulfur Bacteria
Photosynthetic bacteria (PSB) are procaryotes capable of carrying out photosynthesis by converting light energy into chemical energy. These photosynthetic bacteria can either grow in the presence or absence of oxygen (aerobic and anaerobic conditions) and can either use organic or inorganic substances as an electron donor to fix the atmospheric nitrogen (N2) and carbon dioxide (CO2). The purple non-sulfur bacteria belong to the anoxygenic group of PSB, and their major groups include Rhodopseudomonas spp. and Rhodobacter spp. They are naturally present in wastewater ponds, lagoons, lakes, sediments, wetland ecosystems, moist soils, hypersaline systems, and marine ecosystems. They possess versatile metabolic pathways and, therefore, are widely used in the livestock and fisheries industries , in bioremedial methods for heavy metals and sewage, and in biofuel production (electricity or photohydrogen). Studies have also shown that purple non-sulfur bacteria (PNSB) help boost soil fertility when applied directly to the soil, whereas PNSB applied to plants help improve crop growth and yield.
  • 5.0K
  • 14 Oct 2022
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