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Topic Review
Old Spanish Language
Old Spanish, also known as Old Castilian (Spanish: castellano antiguo; Template:Lang-osp [roˈmantse kasteˈʎano]) or Medieval Spanish (Spanish: español medieval), was originally a colloquial Latin spoken in the provinces of the Roman Empire that provided the root for the early form of the Spanish language that was spoken on the Iberian Peninsula from the 10th century until roughly the beginning of the 15th century, before a consonantal readjustment gave rise to the evolution of modern Spanish. The poem Cantar de Mio Cid (The Poem of the Cid), published around 1200, remains the best known and most extensive work of literature in Old Spanish.
  • 7.5K
  • 26 Oct 2022
Topic Review
The Intelligent Reflecting Surface
The Intelligent Reflecting Surface (IRS) is a revolutionary technology to improve the performance of wireless data transmission systems. In particular, the wireless signal transmission environment is reconfigured by jointly adjusting a large number of small reflective units
  • 7.5K
  • 08 Apr 2022
Topic Review
Copper(II) Complex
A dinuclear copper(II) complex of (1) (where bipy = 2,2′‑bipyridine, bzt = benzoate and ox = oxalate) was synthesised and characterised by diffractometric (powder and single-crystal XRD) and thermogravimetric (TG/DTG) analyses, spectroscopic techniques (IR, Raman, electron paramagnetic resonance spectroscopy (EPR) and electronic spectroscopy), magnetic measurements and density functional theory (DFT) calculations. The analysis of the crystal structure revealed that the oxalate ligand is in bis(bidentate) coordination mode between two copper(II) centres. The other four positions of the coordination environment of the copper(II) ion are occupied by one water molecule, a bidentate bipy and a monodentate bzt ligand. An inversion centre located on the ox ligand generates the other half of the dinuclear complex. Intermolecular hydrogen bonds and pi-pi for the organisation of the molecules in the solid state. Molar magnetic susceptibility and field dependence magnetisation studies evidenced a weak intramolecular–ferromagnetic interaction (J = +2.9 cm‑1) between the metal ions. The sign and magnitude of the calculated J value by density functional theory (DFT) are in agreement with the experimental data.
  • 7.5K
  • 30 Oct 2020
Topic Review
Smart manufacturing, an advanced form of traditional manufacturing
Traditional manufacturing is an industrial process that converts materials into a finished product using a labor-intensive low-end operation, low precision, average resource utilization and efficiency for economic value.
  • 7.5K
  • 28 Mar 2022
Topic Review
Spray Congealing Technology
Spray congealing is an emerging technology for the production of solid dispersion to enhance the bioavailability of poorly soluble drugs by using low-melting hydrophilic excipients. Since the '90s, spray congealing technology has been used to obtain microparticles (MPs) for controlled release, taste masking and stability enhancement of APIs. The main advantages are the absence of solvents and the possibility to obtain free-flowing MPs by a relatively inexpensive, simple and one step process. This entry focused on the application of spary congealing as an amerging technology for the production of solid dispersions to enhance the bioavailability of poorly water soluble drugs by using low-melting hydrophilic excipients.
  • 7.5K
  • 14 Dec 2021
Topic Review
Jojoba Oil
Jojoba is a widely used medicinal plant that is cultivated worldwide. Its seeds and oil have a long history of use in folklore to treat various ailments, such as skin and scalp disorders, superficial wounds, sore throat, obesity, and cancer; for improvement of liver functions, enhancement of immunity, and promotion of hair growth. Extensive studies on Jojoba oil showed a wide range of pharmacological applications, including antioxidant, anti-acne and antipsoriasis, anti-inflammatory, antifungal, antipyretic, analgesic, antimicrobial, and anti-hyperglycemia activities. In addition, Jojoba oil is widely used in the pharmaceutical industry, especially in cosmetics for topical, transdermal, and parenteral preparations. Jojoba oil also holds value in the industry as an anti-rodent, insecticides, lubricant, surfactant, and a source for the production of bioenergy. Jojoba oil is considered among the top-ranked oils due to its wax, which constitutes about 98% (mainly wax esters, few free fatty acids, alcohols, and hydrocarbons). In addition, sterols and vitamins with few triglyceride esters, flavonoids, phenolic and cyanogenic compounds are also present. 
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  • 03 Jun 2021
Topic Review
Commune (Model of Government)
The commune, as a model of government, is generally advocated by some communists, revolutionary socialists, and anarchists. Communes are an organizational community with social cohesion derived from a shared culture. As a governing community, a commune often entails some degree of local governance, communal ownership, and cultural cohesion. However, models that do not include all three aspects may still be described as communes. At its core, a commune is just an organization which creates social conditions that prioritize the primacy of the collective over the individual. Many different forms of commune-based governments are possible, such as a local and sovereign community which is both a microstate and a nation-state, a federated commune which lacks a degree of sovereignty under the rule of a larger state, or a larger national community which focuses more on aspects of communal ownership rather than communal governance.
  • 7.5K
  • 09 Nov 2022
Topic Review
Short-Chain Fatty Acids
The relationship between diet and the diversity and function of the intestinal microbiome and its importance for human health is currently the subject of many studies. The type and proportion of microorganisms found in the intestines can determine the energy balance of the host. Intestinal microorganisms perform many important functions, one of which is participation in metabolic processes, e.g., in the production of short-chain fatty acids—SCFAs (also called volatile fatty acids). These acids represent the main carbon flow from the diet to the host microbiome. Maintaining intestinal balance is necessary to maintain the host’s normal health and prevent many diseases. The results of many studies confirm the beneficial effect of probiotic microorganisms on the balance of the intestinal microbiome and produced metabolites, including SCFAs. The aim of this review is to summarize what is known on the effects of probiotics on the production of short-chain fatty acids by gut microbes. In addition, the mechanism of formation and properties of these metabolites is discussed and verified test results confirming the effectiveness of probiotics in human nutrition by modulating SCFAs production by intestinal microbiome is presented.
  • 7.5K
  • 30 Oct 2020
Topic Review
The Evolution of Food Security
Food security is one of the most challenging topics globally; however, the concept of food security has taken on additional dimensions that are general and are less detailed. Recognizing the factors that directly and indirectly affect food security will enable future researchers to focus on and study important topics. One of the important indicators of sustainable development is eliminating hunger and ensuring sustainable food security. International organizations and the WHO have various programs and measures to achieve this goal. The consequences of food insecurity, including hunger, malnutrition, and its direct or indirect effects on health and quality of life, have always been considered.
  • 7.5K
  • 23 Mar 2022
Topic Review
Control Freak
In the slang of psychology, the colloquial term control freak describes a person with a personality disorder characterized by undermining other people, usually by way of controlling behavior manifested in the ways that they act to dictate the order of things in a social situation. The term control freak was first used in the 1970s, a decade when the cultural Zeitgeist featured liberal social norms, which espoused the live-and-let-live principle of "Do your own thing" in opposition to the perceived requirement of social conformity within traditional conservatism.
  • 7.5K
  • 19 Oct 2022
Topic Review
Pathogenic Bacteria
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. By contrast, several thousand species are part of the gut flora present in the digestive tract. The body is continually exposed to many species of bacteria, including beneficial commensals, which grow on the skin and mucous membranes, and saprophytes, which grow mainly in the soil and in decaying matter. The blood and tissue fluids contain nutrients sufficient to sustain the growth of many bacteria. The body has defence mechanisms that enable it to resist microbial invasion of its tissues and give it a natural immunity or innate resistance against many microorganisms. Pathogenic bacteria are specially adapted and endowed with mechanisms for overcoming the normal body defences, and can invade parts of the body, such as the blood, where bacteria are not normally found. Some pathogens invade only the surface epithelium, skin or mucous membrane, but many travel more deeply, spreading through the tissues and disseminating by the lymphatic and blood streams. In some rare cases a pathogenic microbe can infect an entirely healthy person, but infection usually occurs only if the body's defence mechanisms are damaged by some local trauma or an underlying debilitating disease, such as wounding, intoxication, chilling, fatigue, and malnutrition. In many cases, it is important to differentiate infection and colonization, which is when the bacteria are causing little or no harm. Caused by Mycobacterium tuberculosis bacteria, one of the diseases with the highest disease burden is tuberculosis, which killed 1.4 million people in 2019, mostly in sub-Saharan Africa. Pathogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus, Pneumococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter, and Salmonella. Pathogenic bacteria also cause infections such as tetanus, typhoid fever, diphtheria, syphilis, and leprosy. Pathogenic bacteria are also the cause of high infant mortality rates in developing countries. Most pathogenic bacteria can be grown in cultures and identified by Gram stain and other methods. Bacteria grown in this way are often tested to find which antibiotics will be an effective treatment for the infection. For hitherto unknown pathogens, Koch's postulates are the standard to establish a causative relationship between a microbe and a disease.
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  • 07 Nov 2022
Topic Review
Histopathology of Colorectal Carcinoma
The histopathology of colorectal carcinoma involves analysis of tissue taken from a biopsy or surgery. A pathology report contains a description of the microscopical characteristics of the tumor tissue, including both tumor cells and how the tumor invades into healthy tissues and finally if the tumor appears to be completely removed. The most common form of colon cancer is adenocarcinoma, constituting between 95% to 98% of all cases of colorectal cancer. Other, rarer types include lymphoma, adenosquamous and squamous cell carcinoma. Some subtypes have been found to be more aggressive.
  • 7.5K
  • 09 Nov 2022
Topic Review
Dromaeosauridae
Dromaeosauridae (/ˌdrɒmi.əˈsɔːrɪdiː/) is a family of feathered theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek δρομεῦς (dromeûs), meaning 'runner', and σαῦρος (saûros), meaning 'lizard'. In informal usage, they are often called raptors (after Velociraptor), a term popularized by the film Jurassic Park; a few types include the term "raptor" directly in their name and have come to emphasize their bird-like appearance and speculated bird-like behavior. Dromaeosaurid fossils have been found across the globe in North America, Europe, Africa, Asia, South America and Antarctica, with some fossils giving credence to the possibility that they inhabited Australia as well. They first appeared in the mid-Jurassic Period (late Bathonian stage, about 167 million years ago) and survived until the end of the Cretaceous (Maastrichtian stage, 66 ma), existing until the Cretaceous–Paleogene extinction event. The presence of dromaeosaurids as early as the Middle Jurassic has been suggested by the discovery of isolated fossil teeth, though no dromaeosaurid body fossils have been found from this period.
  • 7.5K
  • 07 Nov 2022
Topic Review
Younger Dryas
The Younger Dryas (around 12,900 to 11,700 years BP) was a return to glacial conditions after the Late Glacial Interstadial, which temporarily reversed the gradual climatic warming after the Last Glacial Maximum (LGM) started receding around 20,000 BP. It is named after an indicator genus, the alpine-tundra wildflower Dryas octopetala, as its leaves are occasionally abundant in late glacial, often minerogenic-rich sediments, such as the lake sediments of Scandinavia. Physical evidence of a sharp decline in temperature over most of the Northern Hemisphere has been discovered by geological research. This temperature change occurred at the end of what the earth sciences refer to as the Pleistocene epoch and immediately before the current, warmer Holocene epoch. In archaeology, this time frame coincides with the final stages of the Upper Paleolithic in many areas. The Younger Dryas was the most recent and longest of several interruptions to the gradual warming of the Earth's climate since the severe LGM, about 27,000 to 24,000 years BP. The change was relatively sudden, taking place in decades, and it resulted in a decline of temperatures in Greenland by 4 to 10°C (7.2 to 18°F) and advances of glaciers and drier conditions, over much of the temperate Northern Hemisphere. It is thought to have been caused by a decline in the strength of the Atlantic meridional overturning circulation, which transports warm water from the Equator towards the North Pole, in turn thought to have been caused by an influx of fresh, cold water from North America to the Atlantic. The Younger Dryas was a period of climatic change, but the effects were complex and variable. In the Southern Hemisphere and some areas of the Northern Hemisphere, such as southeastern North America, a slight warming occurred.
  • 7.4K
  • 14 Oct 2022
Topic Review
Medium-Voltage Switchgear Condition Monitoring
Switchgear are a key component of the electrical grid. They serve both protective and control roles in distribution electric power with in the grid. It is therefore important to monitor and predict the condition of these assets. Thereby, condition monitoring is divided into three main tasks: breaker drive monitoring, thermal monitoring and partial discharge monitoring. This encyclopedia article provides an overview of the potential failure modes and monitoring techniques. More details can be found in an exhaustive review article, cited below.
  • 7.4K
  • 29 Oct 2020
Topic Review
Proofs of Fermat's Theorem on Sums of Two Squares
Fermat's theorem on sums of two squares asserts that an odd prime number p can be expressed as with integer x and y if and only if p is congruent to 1 (mod 4). The statement was announced by Girard in 1625, and again by Fermat in 1640, but neither supplied a proof. The "only if" clause is easy: a perfect square is congruent to 0 or 1 modulo 4, hence a sum of two squares is congruent to 0, 1, or 2. An odd prime number is congruent to either 1 or 3 modulo 4, and the second possibility has just been ruled out. The first proof that such a representation exists was given by Leonhard Euler in 1747 and was complicated. Since then, many different proofs have been found. Among them, the proof using Minkowski's theorem about convex sets and Don Zagier's short proof based on involutions have appeared.
  • 7.4K
  • 11 Nov 2022
Topic Review
Reindeer Distribution
The reindeer is a widespread and numerous species in the northern Holarctic, being present in both tundra and taiga (boreal forest). Originally, the reindeer was found in Scandinavia, eastern Europe, Russia , Mongolia, and northern China north of the 50th latitude. In North America, it was found in Canada , Alaska (United States ), and the northern contiguous USA from Washington to Maine. In the 19th century, it was apparently still present in southern Idaho. It also occurred naturally on Sakhalin, Greenland, and probably even in historical times in Ireland. During the late Pleistocene era, reindeer were found further south, such as at Nevada, Tennessee , and Alabama in North America and Spain in Europe. Today, wild reindeer have disappeared from many areas within this large historical range, especially from the southern parts, where it vanished almost everywhere. Populations of wild reindeer are still found in Norway , Finland , Siberia, Greenland, Alaska, and Canada . Domesticated reindeer are mostly found in northern Fennoscandia and Russia, with a herd of approximately 150–170 semi-domesticated reindeer living around the Cairngorms region in Scotland. The last remaining wild tundra reindeer in Europe are found in portions of southern Norway . A few reindeer from Norway were introduced to the South Atlantic island of South Georgia in the beginning of the 20th century. The South Georgian reindeer totaled some estimated 2600 animals in two distinct herds separated by glaciers. Although the flag and the coat of arms of the territory contain an image of a reindeer, they were eradicated from 2013 to 2017 because of the environmental damage they caused. Around 4000 reindeer have been introduced into the French sub-Antarctic archipelago of Kerguelen Islands. East Iceland has a small herd of about 2500–3000 animals. Caribou and reindeer numbers have fluctuated historically, but many herds are in decline across their range. This global decline is linked to climate change for northern, migratory caribou and reindeer herds and industrial disturbance of caribou habitat for sedentary, non-migratory herds.
  • 7.4K
  • 28 Nov 2022
Topic Review
2010 Flash Crash
The May 6, 2010, Flash Crash, also known as the Crash of 2:45, the 2010 Flash Crash or simply the Flash Crash, was a United States trillion-dollar stock market crash, which started at 2:32 p.m. EDT and lasted for approximately 36 minutes.:1 Stock indexes, such as the S&P 500, Dow Jones Industrial Average and Nasdaq Composite, collapsed and rebounded very rapidly. The Dow Jones Industrial Average had its second biggest intraday point drop (from the opening) up to that point, plunging 998.5 points (about 9%), most within minutes, only to recover a large part of the loss. It was also the second-largest intraday point swing (difference between intraday high and intraday low) up to that point, at 1,010.14 points. The prices of stocks, stock index futures, options and exchange-traded funds (ETFs) were volatile, thus trading volume spiked.:3 A CFTC 2014 report described it as one of the most turbulent periods in the history of financial markets.:1 When new regulations put in place following the 2010 Flash Crash proved to be inadequate to protect investors in the August 24, 2015 flash crash—"when the price of many ETFs appeared to come unhinged from their underlying value"—ETFs were put under greater scrutiny by regulators and investors. On April 21, 2015, nearly five years after the incident, the U.S. Department of Justice laid "22 criminal counts, including fraud and market manipulation" against Navinder Singh Sarao, a trader. Among the charges included was the use of spoofing algorithms; just prior to the Flash Crash, he placed thousands of E-mini S&P 500 stock index futures contracts which he planned on canceling later. These orders amounting to about "$200 million worth of bets that the market would fall" were "replaced or modified 19,000 times" before they were canceled. Spoofing, layering, and front running are now banned. The Commodity Futures Trading Commission (CFTC) investigation concluded that Sarao "was at least significantly responsible for the order imbalances" in the derivatives market which affected stock markets and exacerbated the flash crash. Sarao began his alleged market manipulation in 2009 with commercially available trading software whose code he modified "so he could rapidly place and cancel orders automatically." Traders Magazine journalist, John Bates, argued that blaming a 36-year-old small-time trader who worked from his parents' modest stucco house in suburban west London for sparking a trillion-dollar stock market crash is a little bit like blaming lightning for starting a fire" and that the investigation was lengthened because regulators used "bicycles to try and catch Ferraris." Furthermore, he concluded that by April 2015, traders can still manipulate and impact markets in spite of regulators and banks' new, improved monitoring of automated trade systems. As recently as May 2014, a CFTC report concluded that high-frequency traders "did not cause the Flash Crash, but contributed to it by demanding immediacy ahead of other market participants.":1 Some recent peer-reviewed research shows that flash crashes are not isolated occurrences, but have occurred quite often. Gao and Mizrach studied US equities over the period of 1993–2011. They show that breakdowns in market quality (such as flash crashes) have occurred in every year they examined and that, apart from the financial crisis, such problems have declined since the introduction of Reg NMS. They also show that 2010, while infamous for the Flash Crash, was not a year with an inordinate number of breakdowns in market quality.
  • 7.4K
  • 30 Nov 2022
Topic Review
Nose Ring (Animal)
A nose ring is inserted into the nose of an animal. Nose rings are used to control bulls and occasionally cows, and to help wean young cattle by preventing suckling. Nose rings are used on pigs to discourage rooting. Some nose rings are installed through a pierced hole in the nasal septum or rim of the nose and remain there, while others are temporary tools.
  • 7.4K
  • 03 Nov 2022
Topic Review
Physiology of Plant Responses to Water Stress
Drought and waterlogging seriously affect the growth of plants and are considered severe constraints on agricultural and forestry productivity; their frequency and degree have increased over time due to global climate change. The morphology, photosynthetic activity, antioxidant enzyme system and hormone levels of plants could change in response to water stress. 
  • 7.4K
  • 23 May 2022
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