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Topic Review
Rice Husk
The development of engineered silica particles by using low-cost renewable or waste resources is a key example of sustainability. Rice husks have emerged as a renewable resource for the production of engineered silica particles as well as bioenergy.
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  • 17 Jan 2022
Topic Review
Ballad
A ballad is a form of verse, often a narrative set to music. Ballads derive from the medieval French chanson balladée or ballade, which were originally "dance songs". Ballads were particularly characteristic of the popular poetry and song of Britain and Ireland from the later medieval period until the 19th century. They were widely used across Europe, and later in Australia, North Africa, North America and South America. Ballads are often 13 lines with an ABABBCBC form, consisting of couplets (two lines) of rhymed verse, each of 14 syllables. Another common form is ABAB or ABCB repeated, in alternating 8 and 6 syllable lines. Many ballads were written and sold as single sheet broadsides. The form was often used by poets and composers from the 18th century onwards to produce lyrical ballads. In the later 19th century, the term took on the meaning of a slow form of popular love song and is often used for any love song, particularly the sentimental ballad of pop or rock music, although the term is also associated with the concept of a stylized storytelling song or poem, particularly when used as a title for other media such as a film.
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  • 04 Nov 2022
Topic Review
Broadcasting of Sports Events
The broadcasting of sports events (also known as a sportscast) is the live coverage of sports as a television program, on radio, and other broadcasting media. It usually involves one or more sports commentators describing events as they happen.
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  • 01 Dec 2022
Topic Review
6 February 1934 Crisis
The 6 February 1934 crisis was an anti-parliamentarist street demonstration in Paris organized by multiple far-right leagues that culminated in a riot on the Place de la Concorde, near the seat of the French National Assembly. The police shot and killed 15 demonstrators. It was one of the major political crises during the Third Republic (1870–1940). Frenchmen on the left feared it was an attempt to organize a fascist coup d'état. According to historian Joel Colton, "The consensus among scholars is that there was no concerted or unified design to seize power and that the leagues lacked the coherence, unity, or leadership to accomplish such an end." As a result of the actions of that day, several anti-fascist organisations were created, such as the Comité de vigilance des intellectuels antifascistes, in an attempt to thwart the rise of fascism in France. After World War II, several historians, among them Serge Berstein, argued that while some leagues had been indisputably pushing for a coup, François de La Rocque had, in fact, turned in a liberal direction, toward a respect for constitutional order. However, if the lack of coordination among the fascist leagues undermined the idea of a fascist conspiracy, the fascist actions on 6 February were an uncoordinated but violent attempt to overthrow the Cartel des gauches government elected in 1932. Édouard Daladier, who was president of the Council of Ministers, replaced Camille Chautemps on 27 January 1934 because of accusations of corruption (including the Stavisky Affair). Daladier, who had been a popular figure, was nonetheless forced to resign on 7 February. He was replaced by the conservative Gaston Doumergue as head of the government; this was the first time during the tenure of the Third Republic a government fell because of pressures from the street.
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  • 21 Nov 2022
Topic Review
Deformation (Engineering)
In engineering, deformation refers to the change in size or shape of an object. Displacements are the absolute change in position of a point on the object. Deflection is the relative change in external displacements on an object. Strain is the relative internal change in shape of an infinitesimally small cube of material and can be expressed as a non-dimensional change in length or angle of distortion of the cube. Strains are related to the forces acting on the cube, which are known as stress, by a stress-strain curve. The relationship between stress and strain is generally linear and reversible up until the yield point and the deformation is elastic. The linear relationship for a material is known as Young's modulus. Above the yield point, some degree of permanent distortion remains after unloading and is termed plastic deformation. The determination of the stress and strain throughout a solid object is given by the field of strength of materials and for a structure by structural analysis. Engineering stress and engineering strain are approximations to the internal state that may be determined from the external forces and deformations of an object, provided that there is no significant change in size. When there is a significant change in size, the true stress and true strain can be derived from the instantaneous size of the object. In the figure it can be seen that the compressive loading (indicated by the arrow) has caused deformation in the cylinder so that the original shape (dashed lines) has changed (deformed) into one with bulging sides. The sides bulge because the material, although strong enough to not crack or otherwise fail, is not strong enough to support the load without change. As a result, the material is forced out laterally. Internal forces (in this case at right angles to the deformation) resist the applied load. The concept of a rigid body can be applied if the deformation is negligible.
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  • 24 Oct 2022
Topic Review
Zip (File Format)
ZIP files generally use the file extensions .zip or .ZIP and the MIME media type application/zip. ZIP is used as a base file format by many programs, usually under a different name. When navigating a file system via a user interface, graphical icons representing ZIP files often appear as a document or other object prominently featuring a zipper.
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  • 14 Oct 2022
Topic Review
Direct Contact Condensers
Direct contact heat exchangers can be smaller, cheaper, and have simpler construction than the surface, shell, or tube heat exchangers of the same capacity and can operate in evaporation or condensation modes. For these reasons, they have many practical applications, such as water desalination, heat exchangers in power plants, or chemical engineering devices.
  • 7.5K
  • 23 Dec 2022
Topic Review
Minimalist Program
In linguistics, the minimalist program (MP) is a major line of inquiry that has been developing inside generative grammar since the early 1990s, starting with a 1993 paper by Noam Chomsky. Chomsky presents MP as a program, not as a theory, following Imre Lakatos's distinction. The MP seeks to be a mode of inquiry characterized by the flexibility of the multiple directions that its minimalism enables. Ultimately, the MP provides a conceptual framework used to guide the development of linguistic theory. In minimalism, Chomsky attempts to approach universal grammar from below—that is, proposing the question "what would be the optimal answer to what the theory of i-Language should be?" For Chomsky, there are minimalist questions, but the answers can be framed in any theory. Of all these questions, the two that play the most crucial role are:
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  • 20 Nov 2022
Topic Review
Precambrian Supereon
The Precambrian (or Pre-Cambrian, sometimes abbreviated pЄ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic eon, which is named after Cambria, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian (colored green in the timeline figure) is an informal unit of geologic time, subdivided into three eons (Hadean, Archean, Proterozoic) of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago (Ga) to the beginning of the Cambrian Period, about 541 million years ago (Ma), when hard-shelled creatures first appeared in abundance.
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  • 18 Oct 2022
Topic Review
Cultural Heritage and Tourism
The integration of the cultural/creative and tourism industries is one way to present different types of regional cultural heritage to the world. With the growth of scenic towns and the revitalization of rural areas due to mass tourism, intangible cultural heritage has become an important tourism and cultural resource. The numbers of domestic and foreign tourists visiting these traditional cultural resources are on the rise every year. Many areas with rich cultural resources rely on tourism to alleviate poverty and achieve revitalization. However, a region’s tourism resources are not always proportional to its cultural heritage. It is important to carefully study the methods of regional tourism resource development, while also fully integrating cultural resources.
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  • 30 Jun 2022
Topic Review
ISO Standards for Trailer Connectors
A number of ISO standards cover trailer connectors, the electrical connectors between vehicles and the trailers they tow that provide a means of control for the trailers. These are listed below, with notes on significant deviations from them that can cause problems.
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  • 07 Nov 2022
Topic Review
Processing of Cereals and Derived-By-Products
Cereals have been one of the major food resources for human diets and animal feed for thousands of years, and a large quantity of by-products is generated throughout the entire processing food chain, from farm to fork. These by-products mostly consist of the germ and outer layers (bran) derived from dry and wet milling of the grains, of the brewers’ spent grain generated in the brewing industry, or comprise other types obtained from the breadmaking and starch production industries. Cereal processing by-products are an excellent low-cost source of various compounds such as dietary fibres, proteins, carbohydrates and sugars, minerals and antioxidants (such as polyphenols and vitamins), among others. Often, they are downgraded and end up as waste or, in the best case, are used as animal feed or fertilizers. With the increase in world population coupled with the growing awareness about environmental sustainability and healthy life-styles and well-being, the interest of the industry and the global market to provide novel, sustainable and innovative solutions for the management of cereal-based by-products is also growing rapidly.
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  • 15 Sep 2020
Topic Review
BMW X5 (E70)
The BMW E70 is the second-generation BMW X5 mid-size luxury crossover SUV. It replaced the BMW X5 (E53) in July 2006. It was manufactured alongside the BMW X6 at BMW's Greer, South Carolina plant in the U.S. and BMW's facility in Toluca, Mexico.
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  • 29 Nov 2022
Topic Review
Beeswax
Beeswax is one of the natural waxes that have been used as a support ingredient in cosmetic and pharmaceutical formulations. Although it has well-known healing properties, it remains a secondary and poorly valued product, particularly in South American countries' apiarian production. In Latin America, for example, the apiarian activity can be traced back to stingless bees in pre-Columbian times. Then, with the arrival of the Spaniards in the 16th century, honey bees (Apis mellifera iberian and A. m. mellifera) were introduced, which were joined afterward by other breeds such as A. m. ligustica and A. m. scutellata. Over the years, honey has been the main product from the apiarian farmers, being beeswax a secondary product, mainly used for the regular renewal procedure of the hives. Nowadays, beeswax's cosmetic and pharmaceutical use is found at the level of small laboratories and small businesses.
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  • 10 Oct 2022
Topic Review
Ideas of Reference and Delusions of Reference
Ideas of reference and delusions of reference describe the phenomenon of an individual experiencing innocuous events or mere coincidences and believing they have strong personal significance. It is "the notion that everything one perceives in the world relates to one's own destiny", usually in a negative and hostile manner. In psychiatry, delusions of reference form part of the diagnostic criteria for psychotic illnesses such as schizophrenia, delusional disorder, bipolar disorder (during the elevated stages of mania), as well as schizotypal personality disorder. To a lesser extent, it can be a hallmark of paranoid personality disorder, as well as body dysmorphic disorder. Such symptoms can also be caused by intoxication, such as stimulants like methamphetamine.
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  • 20 Oct 2022
Topic Review
History of Nanotechnology
The history of nanotechnology traces the development of the concepts and experimental work falling under the broad category of nanotechnology. Although nanotechnology is a relatively recent development in scientific research, the development of its central concepts happened over a longer period of time. The emergence of nanotechnology in the 1980s was caused by the convergence of experimental advances such as the invention of the scanning tunneling microscope in 1981 and the discovery of fullerenes in 1985, with the elucidation and popularization of a conceptual framework for the goals of nanotechnology beginning with the 1986 publication of the book Engines of Creation. The field was subject to growing public awareness and controversy in the early 2000s, with prominent debates about both its potential implications as well as the feasibility of the applications envisioned by advocates of molecular nanotechnology, and with governments moving to promote and fund research into nanotechnology. The early 2000s also saw the beginnings of commercial applications of nanotechnology, although these were limited to bulk applications of nanomaterials rather than the transformative applications envisioned by the field.
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  • 17 Oct 2022
Topic Review
Skin-Lightening Active Ingredients in Japan
Japanese pharmaceutical cosmetics, often referred to as quasi-drugs, contain skin-lightening active ingredients formulated to prevent sun-induced pigment spots and freckles. Their mechanisms of action include suppressing melanin production in melanocytes and promoting epidermal growth to eliminate melanin more rapidly. For example, arbutin and rucinol are representative skin-lightening active ingredients that inhibit melanin production, and disodium adenosine monophosphate and dexpanthenol are skin-lightening active ingredients that inhibit melanin accumulation in the epidermis. In contrast, oral administration of vitamin C and tranexamic acid in pharmaceutical products can lighten freckles and melasma, and these products are more effective than quasi-drugs. On the basis of their clinical effectiveness, skin-lightening active ingredients can be divided into four categories according to their effectiveness and adverse effects.
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  • 08 Aug 2022
Topic Review
Hockey Stick Controversy
In the hockey stick controversy, the data and methods used in reconstructions of the temperature record of the past 1000 years have been disputed. Reconstructions have consistently shown that the rise in the instrumental temperature record of the past 150 years is not matched in earlier centuries, and the name "hockey stick graph" was coined for figures showing a long-term decline followed by an abrupt rise in temperatures. These graphs were publicised to explain the scientific findings of climatology, and in addition to scientific debate over the reconstructions, they have been the topic of political dispute. The issue is part of the global warming controversy and has been one focus of political responses to reports by the Intergovernmental Panel on Climate Change (IPCC). Arguments over the reconstructions have been taken up by fossil fuel industry–funded lobbying groups attempting to cast doubt on climate science. The use of proxy indicators to get quantitative estimates of the temperature record of past centuries was developed from the 1990s onwards, and found indications that recent warming was exceptional. The Bradley & Jones 1993 reconstruction introduced the "Composite Plus Scaling" (CPS) method used by most later large-scale reconstructions, and its findings were disputed by Patrick Michaels at the United States House Committee on Science. In 1998, Michael E. Mann, Raymond S. Bradley and Malcolm K. Hughes developed new statistical techniques to produce Mann, Bradley & Hughes 1998 (MBH98), the first eigenvector-based climate field reconstruction (CFR). This showed global patterns of annual surface temperature, and included a graph of average hemispheric temperatures back to 1400. In Mann, Bradley & Hughes 1999 (MBH99) the methodology was extended back to 1000. The term hockey stick was coined by the climatologist Jerry D. Mahlman, to describe the pattern this showed, envisaging a graph that is relatively flat to 1900 as forming an ice hockey stick's "shaft", followed by a sharp increase corresponding to the "blade". A version of this graph was featured prominently in the 2001 IPCC Third Assessment Report (TAR), along with four other reconstructions supporting the same conclusion. The graph was publicised, and became a focus of dispute for those opposed to the strengthening scientific consensus that late 20th-century warmth was exceptional. Those disputing the graph included Pat Michaels, the George C. Marshall Institute and Fred Singer. A paper by Willie Soon and Sallie Baliunas claiming greater medieval warmth was used by the Bush administration chief of staff Philip Cooney to justify altering the first Environmental Protection Agency Report on the Environment. The paper was quickly dismissed by scientists in the Soon and Baliunas controversy, but on July 28, Republican Jim Inhofe spoke in the Senate citing it to claim "that man-made global warming is the greatest hoax ever perpetrated on the American people". Later in 2003, a paper by Steve McIntyre and Ross McKitrick disputing the data used in MBH98 paper was publicised by the George C. Marshall Institute and the Competitive Enterprise Institute. In 2004, Hans von Storch published criticism of the statistical techniques as tending to underplay variations in earlier parts of the graph, though this was disputed and he later accepted that the effect was very small. In 2005, McIntyre and McKitrick published criticisms of the principal component analysis methodology as used in MBH98 and MBH99. The analysis therein was subsequently disputed by published papers, including Huybers 2005 and Wahl & Ammann 2007, which pointed to errors in the McIntyre and McKitrick methodology. In June 2005, Rep. Joe Barton launched what Sherwood Boehlert, chairman of the House Science Committee, called a "misguided and illegitimate investigation" into the data, methods and personal information of Mann, Bradley and Hughes. At Boehlert's request, a panel of scientists convened by the National Research Council was set up, which reported in 2006, supporting Mann's findings with some qualifications, including agreeing that there were some statistical failings but these had little effect on the result. Barton and U.S. Rep. Ed Whitfield requested Edward Wegman to set up a team of statisticians to investigate, and they supported McIntyre and McKitrick's view that there were statistical failings, although they did not quantify whether there was any significant effect. They also produced an extensive network analysis which has been discredited by expert opinion and found to have issues of plagiarism. Arguments against the MBH studies were reintroduced as part of the Climatic Research Unit email controversy, but dismissed by eight independent investigations. More than two dozen reconstructions, using various statistical methods and combinations of proxy records, have supported the broad consensus shown in the original 1998 hockey-stick graph, with variations in how flat the pre-20th century "shaft" appears. The 2007 IPCC Fourth Assessment Report cited 14 reconstructions, 10 of which covered 1,000 years or longer, to support its strengthened conclusion that it was likely that Northern Hemisphere temperatures during the 20th century were the highest in at least the past 1,300 years. Over a dozen subsequent reconstructions, including Mann et al. 2008 and PAGES 2k Consortium 2013, have supported these general conclusions.
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  • 21 Oct 2022
Topic Review
Food Waste Management in Bangladesh
Food waste management is a critical environmental issue in many developing countries, including Bangladesh, due to unplanned food waste disposal and lack of dedicated food waste legislation. In those countries, a significant amount of food waste is discarded to the environment rather than being recycled. In Bangladesh, food waste is traditionally often used for composting, landfilling, and feeding animals, as there is no valorization option. In addition, food waste and food waste streams of food industries are utilized for the recycling and production of diverse economically valuable bioactive compounds.
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  • 18 Oct 2022
Topic Review
2D-MoS2
Two-dimensional (2D) materials are generally defined as crystalline substances with a few atoms thickness.Two-dimensional transition metal dichalcogenide (2D-TMDs) semiconducting (SC) materials have exhibited unique optical and electrical properties. The layered configuration of the 2D-TMDs materials is at the origin of their strong interaction with light and the relatively high mobility of their charge carriers, which in turn prompted their use in many optoelectronic applications, such as ultra-thin field-effect transistors, photo-detectors, light emitting diode, and solar-cells. Generally, 2D-TMDs form a family of graphite-like layered thin semiconducting structures with the chemical formula of MX2, where M refers to a transition metal atom (Mo, W, etc.) and X is a chalcogen atom (Se, S, etc.). The layered nature of this class of 2D materials induces a strong anisotropy in their electrical, chemical, mechanical, and thermal properties. In particular, molybdenum disulfide (MoS2) is the most studied layered 2D-TMD.
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  • 28 Sep 2021
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