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Topic Review
African Sheep Breeds
The African continent is home to more than 400 million heads of sheep, the majority of which are classified as indigenous and raised primarily for subsistence. They live and thrive well in a wide range of climatic and production conditions, ranging from unfavorable to favorable environments. 
  • 10.8K
  • 17 Sep 2021
Topic Review
Occupational Stress
Occupational stress is psychological stress related to one's job. Occupational stress refers to a chronic condition. Occupational stress can be managed by understanding what the stressful conditions at work are and taking steps to remediate those conditions. Occupational stress can occur when workers do not feel supported by supervisors or coworkers, feel as if they have little control over the work they perform, or find that their efforts on the job are incommensurate with the job's rewards. Occupational stress is a concern for both employees and employers because stressful job conditions are related to employees' emotional well-being, physical health, and job performance. A landmark study conducted by the World Health Organization and the International Labour Organization found that exposure to long working hours, which are theorized to operate through increased psycho-social occupational stress, is the occupational risk factor with the largest attributable burden of disease, according to these official estimates causing an estimated 745,000 workers to die from ischemic heart disease and stroke events in 2016. A number of disciplines within psychology are concerned with occupational stress including occupational health psychology, human factors and ergonomics, epidemiology, occupational medicine, sociology, industrial and organizational psychology, and industrial engineering.
  • 10.8K
  • 30 Sep 2022
Topic Review
Demonic Possession
Demonic possession is the belief that a person's actions are controlled by an alien spirit, demon, or entity. Symptoms of demonic possession commonly claimed by victims include missing memories, perceptual distortions, loss of a sense of control, and hyper-suggestibility. Erika Bourguignon found in a study of 488 societies worldwide, seventy-four percent believe in possession by spirits, with the highest numbers of beliefs in Pacific cultures and the lowest incidence among Native Americans of both North and South America.
  • 10.8K
  • 25 Nov 2022
Topic Review
Scandinavian Folklore
Scandinavian folklore or Nordic folklore is the folklore of Norway , Sweden, Denmark , Iceland and the Faroe Islands. It has common roots with, and has been mutually influenced by, folklore in England, Germany, the Baltic countries, Finland and Sapmi. Folklore is a concept encompassing expressive traditions of a particular culture or group. The peoples of Scandinavia are heterogenous, as are the oral genres and material culture that has been common in their lands. However, there are some commonalities across Scandinavian folkloric traditions, among them a common ground in elements from Norse mythology as well as Christian conceptions of the world. Among the many tales common in Scandinavian oral traditions, some have become known beyond Scandinavian borders - examples include The Three Billy Goats Gruff and The Giant Who Had No Heart in His Body.
  • 10.8K
  • 19 Oct 2022
Topic Review
Uniaxial Tensile Test
Tensile testing, also known as tension testing, is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. Properties that are directly measured via a tensile test are ultimate tensile strength, breaking strength, maximum elongation and reduction in area. From these measurements the following properties can also be determined: Young's modulus, Poisson's ratio, yield strength, and strain-hardening characteristics. Uniaxial tensile testing is the most commonly used for obtaining the mechanical characteristics of isotropic materials. Some materials use biaxial tensile testing. The main difference between these testing machines being how load is applied on the materials.
  • 10.8K
  • 07 Nov 2022
Biography
Sabrina Gonzalez Pasterski
Sabrina Gonzalez Pasterski (born June 3, 1993) is an American theoretical physicist from Chicago who studies high energy physics.[1] She describes herself as "a proud first-generation Cuban-American & Chicago Public Schools alumna."[2] She completed her undergraduate studies at the Massachusetts Institute of Technology (MIT), earned her PhD from Harvard University and is a rising PCTS Postdoctor
  • 10.8K
  • 12 Dec 2022
Topic Review
Intel 80486
The Intel 80486, also known as the i486 or 486, is a higher performance follow-up to the Intel 80386 microprocessor. The 80486 was introduced in 1989 and was the first tightly pipelined x86 design as well as the first x86 chip to use more than a million transistors, due to a large on-chip cache and an integrated floating-point unit. It represents a fourth generation of binary compatible CPUs since the original 8086 of 1978. A 50 MHz 80486 executes around 40 million instructions per second on average and is able to reach 50 MIPS peak performance. Approximately twice as fast as the 80386 or 80286 per clock cycle, thanks to its five stage pipeline with all stages bound to a single cycle. The on chip enhanced FPU unit was also significantly faster than the 80387 per cycle.
  • 10.8K
  • 03 Nov 2022
Topic Review
Applications of polydimethylsiloxane (PDMS) in Engineering
Polydimethylsiloxane (PDMS) is an elastomer with excellent optical, electrical and mechanical properties, which makes it well-suited for several engineering applications. Due to its biocompatibility, PDMS is widely used for biomedical purposes. Some properties can be improved by adding additives.
  • 10.8K
  • 12 Jan 2022
Topic Review
Vitamin D Synthesis and Metabolism
Vitamin D, conventionally considered a nutrient, is a potent hormone regulating many physiological functions. Vitamin D exists as a prohormone that needs to be transformed into biologically active products that bind to their cognate nuclear receptors to regulate diverse physiological processes.
  • 10.8K
  • 13 Apr 2022
Topic Review
Coffee By-Products
The coffee plant Coffea spp. offers much more than the well-known drink made from the roasted coffee bean. During its cultivation and production, a wide variety of by-products are accrued, most of which are currently unused, thermally recycled, or used as animal feed.
  • 10.8K
  • 02 Nov 2020
Topic Review
Customer Centricity
Firms are increasingly organized around the client. At the same time, there is customer pressure on green and sustainable organizations. This entry joint this two stand points in a sustainable view.
  • 10.8K
  • 03 Mar 2023
Topic Review
Chalk
Chalk is a soft, white, porous, sedimentary carbonate rock, a form of limestone composed of the mineral calcite. Calcite is an ionic salt called calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite shells (coccoliths) shed from micro-organisms called coccolithophores. Flint (a type of chert) is very common as bands parallel to the bedding or as nodules embedded in chalk. It is probably derived from sponge spicules or other siliceous organisms as water is expelled upwards during compaction. Flint is often deposited around larger fossils such as Echinoidea which may be silicified (i.e. replaced molecule by molecule by flint). Chalk, as seen in Cretaceous deposits of Western Europe, is unusual among sedimentary limestones in the thickness of the beds. Most cliffs of chalk have very few obvious bedding planes unlike most thick sequences of limestone such as the Carboniferous Limestone or the Jurassic oolitic limestones. This may indicate very stable conditions over tens of millions of years. Chalk has greater resistance to weathering and slumping than the clays with which it is usually associated, thus forming tall, steep cliffs where chalk ridges meet the sea. Chalk hills, known as chalk downland, usually form where bands of chalk reach the surface at an angle, so forming a scarp slope. Because chalk is well jointed it can hold a large volume of ground water, providing a natural reservoir that releases water slowly through dry seasons.
  • 10.8K
  • 29 Nov 2022
Topic Review
Brilliant Blue FCF
Brilliant Blue FCF (Blue 1) is a synthetic organic compound used primarily as a blue colorant for processed foods, medications, dietary supplements, and cosmetics. It is classified as a triarylmethane dye and is known under various names, such as FD&C Blue No. 1 or Acid Blue 9. It is denoted by E number E133 and has a color index of 42090. It has the appearance of a blue powder and is soluble in water and glycerol, with a maximum absorption at about 628 nanometers. It is one of the oldest FDA-approved color additives and is generally considered nontoxic and safe.
  • 10.7K
  • 17 Nov 2022
Topic Review
Digital Protective Relay
In utility and industrial electric power transmission and distribution systems, a digital protective relay is a computer-based system with software-based protection algorithms for the detection of electrical faults. Such relays are also termed as microprocessor type protective relays. They are functional replacements for electro-mechanical protective relays and may include many protection functions in one unit, as well as providing metering, communication, and self-test functions.
  • 10.7K
  • 09 Oct 2022
Topic Review
Antenna Gain
In electromagnetics, an antenna's power gain or simply gain is a key performance number which combines the antenna's directivity and electrical efficiency. In a transmitting antenna, the gain describes how well the antenna converts input power into radio waves headed in a specified direction. In a receiving antenna, the gain describes how well the antenna converts radio waves arriving from a specified direction into electrical power. When no direction is specified, gain is understood to refer to the peak value of the gain, the gain in the direction of the antenna's main lobe. A plot of the gain as a function of direction is called the gain pattern or radiation pattern. Antenna gain is usually defined as the ratio of the power produced by the antenna from a far-field source on the antenna's beam axis to the power produced by a hypothetical lossless isotropic antenna, which is equally sensitive to signals from all directions. Usually this ratio is expressed in decibels, and these units are referred to as decibels-isotropic (dBi). An alternative definition compares the received power to the power received by a lossless half-wave dipole antenna, in which case the units are written as dBd. Since a lossless dipole antenna has a gain of 2.15 dBi, the relation between these units is [math]\displaystyle{ \mathrm{Gain(dBd)} = \mathrm{Gain(dBi)} - 2.15 }[/math]. For a given frequency, the antenna's effective area is proportional to the power gain. An antenna's effective length is proportional to the square root of the antenna's gain for a particular frequency and radiation resistance. Due to reciprocity, the gain of any reciprocal antenna when receiving is equal to its gain when transmitting. Directive gain or directivity is a different measure which does not take an antenna's electrical efficiency into account. This term is sometimes more relevant in the case of a receiving antenna where one is concerned mainly with the ability of an antenna to receive signals from one direction while rejecting interfering signals coming from a different direction.
  • 10.7K
  • 10 Oct 2022
Biography
E. Michael Jones
Eugene Michael Jones (born May 4, 1948) is an American writer, former professor, media commentator and the current editor of Culture Wars magazine (formerly Fidelity Magazine). Jones is known for his writings from a perspective which defends the Catholic Church in American society and overviews the decline of the Catholic communities which were assimilated into the secular American mainstream af
  • 10.7K
  • 29 Dec 2022
Topic Review
The Transition to Adulthood
The transition to adulthood is a process that brings childhood to an end and turns the individual into a young adult. This process is characterised by the acquisition of new roles for young people, roles linked to the development of personal autonomy that culminate in their emotional and functional independence.
  • 10.7K
  • 31 Aug 2021
Topic Review
Probability Sampling and Non Probability Sampling
There are two types of sampling methods namely: probability sampling and non-probability sampling. Each of these methods includes different types of techniques of sampling. Non-probability Sampling includes Quota sampling, Snowball sampling, Judgment sampling, and Convenience sampling, furthermore,  Probability Sampling includes Simple random, Stratified random, Cluster sampling, Systematic sampling and Multi stage sampling. 
  • 10.7K
  • 18 Feb 2022
Topic Review
Luffa Natural Fiber Composites
Natural fiber composites (NFCs) are an evolving area in polymer sciences. Fibers extracted from natural sources hold a wide set of advantages such as negligible cost, significant mechanical characteristics, low density, high strength-to-weight ratio, environmental friendliness, recyclability, etc. Luffa cylindrica, also termed luffa gourd or luffa sponge, is a natural fiber that has a solid potential to replace synthetic fibers in composite materials in diverse applications like vibration isolation, sound absorption, packaging, etc. Recently, many researches have involved luffa fibers as a reinforcement in the development of NFC, aiming to investigate their performance in selected matrices as well as the behavior of the end NFC.
  • 10.7K
  • 25 Sep 2020
Topic Review
Shenyang J-31
The Shenyang J-31 (or "FC-31 fifth Generation Multi-Purpose light Fighter") also known as the "Gyrfalcon" (鹘鹰), or "Falcon Hawk" by some military enthusiasts, is a twin-engine, mid-size fifth-generation jet fighter currently under development by Shenyang Aircraft Corporation. The fighter has also been referred to as the "F-60" or "J-21 Snowy Owl" (雪鸮) in some media reports. Its official name is Shenyang FC-31; J-xx nomenclatures in the Chinese military are reserved to programs launched and financed by the army, while this plane was developed by a state-owned company.
  • 10.7K
  • 10 Nov 2022
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