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Topic Review
Rock Art
The term ‘rock art’ defines non-utilitarian humanly made markings on natural rock surfaces, caused either by an additive (pictograms, made by the application of material) or a reductive process (petroglyphs, made by the removal of rock material). The former include rock paintings, pigment drawings, stencils, and beeswax figures; the latter term covers engravings, percussion petroglyphs, and finger flutings. Rock art occurs in nearly all countries. Its uneven distribution is attributable to differences in cultural conventions as well as a taphonomic attribute, i.e. a result of preservation bias. Prehistoric rock art represents by far the largest body of evidence we possess of humanity’s cultural, cognitive, and artistic beginnings. Through its relative permanence, it has profoundly influenced the beliefs and cultural conventions of subsequent societies up to the present. It is, therefore, an integral part of humanity's collective memory and the most significant surviving witness of our cultural evolution. 
  • 6.0K
  • 07 Apr 2021
Topic Review
Floating Wind Turbines
Globally, the wind resource in deep water (depths > 60 m) is very abundant. Due to the abundance of potential at these depths, the wind turbines will need the design of a floating platform because the wind turbines that are currently in operation are mostly fixed at the bottom and are dependent upon conventional concrete with a gravity base that is not feasible at these depths. A balance among the two varying principles (i.e., the requirement for a stable foundation for the wind turbine’s control and operation and the nature of the substructure being innate, to respond to environmental forces) is required for the design of the floating platform for wind energy. The absence of rigid foundations results in an additional six degrees of freedom (DOFs) for the platform of floating turbines; three translational (surge X, sway Y, and heave Z) and three rotational (roll RotX, pitch RotY, and yaw RotZ). For the platforms of onshore wind turbines and bottom-mounted offshore wind turbines, the effect of soil-structure interaction (SSI) can be modeled with six degrees of freedom; three translational (horizontal forces in X and Y and vertical force in Z) and three rotational (rocking moments in X and Y and a torsional moment in Z) respectively.
  • 6.0K
  • 11 Oct 2021
Topic Review
Trickster
In mythology, and in the study of folklore and religion, a trickster is a character in a story (god, goddess, spirit, human, or anthropomorphisation), which exhibits a great degree of intellect or secret knowledge, and uses it to play tricks or otherwise disobey normal rules and conventional behaviour.
  • 6.0K
  • 03 Nov 2022
Topic Review
Communalism
Communalism usually refers to a system that integrates communal ownership and federations of highly localized independent communities. A prominent libertarian socialist, Murray Bookchin, defines the Communalism political philosophy that he developed as "a theory of government or a system of government in which independent communes participate in a federation", as well as "the principles and practice of communal ownership". The term 'government' in this case does not imply an acceptance of a State or top-down hierarchy. This usage of communalism appears to have emerged during the late 20th century to distinguish commune-based systems from other political movements and/or governments espousing (if not actually practicing) similar ideas. In particular, earlier communities and movements advocating such practices were often described as "anarchist", "socialist" and/or "communist". Many historical communities practicing utopian socialism or anarcho-communism did implement internal rules of communalist property ownership in the context of federated communalism. It is at least theoretically possible for a federation of communes to include communes which do not practice communalist rules of property, which is to say, that the overall national government may be a federation of communes, but that private property rather than communalist property is the order within each such commune. Karl Marx, often viewed as the founder of modern communism, criticized older forms, including primitive communism and/or utopian socialism, as poorly conceived and/or prone to disintegration in practice. Communalism in the form described above is distinct from the predominant usage in South Asian forms of English: allegiance to a particular ethnic and/or religious group rather than to a broader society. As such, this usage is synonymous with sectarianism and associated with communal violence.
  • 6.0K
  • 16 Nov 2022
Topic Review
Low Intensity Conflict
A low-intensity conflict (LIC) is a military conflict, usually localised, between two or more state or non-state groups which is below the intensity of conventional war. It involves the state's use of military forces applied selectively and with restraint to enforce compliance with its policies or objectives. The term can be used to describe conflicts where at least one or both of the opposing parties operate along such lines.
  • 6.0K
  • 27 Sep 2022
Topic Review
Microgrid and Its Architecture
The world today is plagued with problems of increased transmission and distribution (T&D) losses leading to poor reliability due to power outages and an increase in the expenditure on electrical infrastructure. To address these concerns, technology has evolved to enable the integration of renewable energy sources (RESs) like solar, wind, diesel and biomass energy into small scale self-governing power system zones which are known as micro-grids (MGs). A de-centralised approach for modern power grid systems has led to an increased focus on distributed energy resources and demand response. MGs act as complete power system units albeit on a small scale. However, this does not prevent them from large operational sophistication allowing their independent functioning in both grid-connected and stand-alone modes. MGs provide greater reliability as compared to the entire system owing to the large amount of information secured from the bulk system. They comprise numerous sources like solar, wind, diesel along with storage devices and converters. Several modeling schemes have been devised to reduce the handling burden of large scale systems. 
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  • 18 Jan 2022
Topic Review
Plant Nutrition for Human Health
Is there any relationship between plant nutrition and human health? The overall response to this question is very positive, and a strong relationship between the nutrition of plants and humans has been reported. The nutritional status of edible plants consumed by humans can have a negative or positive impact on human health.
  • 6.0K
  • 14 Jul 2022
Topic Review
Properties and Synthesis of Photocatalysts
The photocatalysts must be characterized by the ability to absorb radiation from a wide spectral range of light, the appropriate position of the semiconductor energy bands in relation to the redox reaction potentials, and the long diffusion path of charge carriers, besides the thermodynamic, electrochemical, and photoelectrochemical stabilities.
  • 6.0K
  • 30 Dec 2022
Topic Review
Tobacco Products
Tobacco is the agricultural product of the leaves of plants in the genus Nicotiana. All species of Nicotiana contain the addictive drug nicotine—a stimulant and sedative contained in all parts of the plants except the seeds—which occurs in varying amounts depending on the species and variety cultivated. See types of tobacco and curing of tobacco for more information. The vast majority of commercially available tobacco is derived from the species Nicotiana tabacum, although it is also produced from Nicotiana alata, and to a lesser extent Nicotiana clevelandii, Nicotiana longiflora, and Nicotiana rustica, among others. N. rustica in particular contains much more nicotine than N. tabacum and other species of Nicotiana, and forms the basis of a number of unique tobacco products, including several preparations used in Latin American shamanic ceremonies. Once tobacco has been grown, harvested, cured, and processed, it is used to produce a number of different products. These are most often consumable; however, tobacco and the nicotine derived from it are also used to create pesticides. Tobacco products can generally be divided into two types: smoked tobacco (see tobacco smoking) and smokeless tobacco. An expert in tobacco and tobacco products — especially pipes, pipe tobacco, and cigars—including their procurement and sale, is called a tobacconist. The health effects of tobacco consumption are discussed in health effects of tobacco.
  • 6.0K
  • 19 Oct 2022
Topic Review
Railway Nationalization
Railway nationalization is the act of taking rail transport assets into public ownership. Several countries have at different times nationalized part or all of their railway system. More recently, the international trend has been towards privatization. In some areas, notably Great Britain, resultant problems with track maintenance have led back to a more mixed solution, with a nationalised infrastructure operator but privately run train operating companies. National characteristics influenced the structures under which countries' rail networks developed. Some national railways were always under direct State management, some were State-planned but privately operated (as in France, others were wholly private enterprises lightly regulated (as in Great Britain, Ireland and Spain). Nationalization was therefore a bolder step to take in some countries than in others. While ideology has played a role, so too has the need for systematic reconstruction of vital infrastructure devastated by war, often following a period of State control over private companies initiated during the conflict.
  • 6.0K
  • 01 Dec 2022
Topic Review
2015–16 Chinese Stock Market Turbulence
The Chinese stock market turbulence began with the popping of the stock market bubble on 12 June 2015 and ended in early February 2016. A third of the value of A-shares on the Shanghai Stock Exchange was lost within one month of the event. Major aftershocks occurred around 27 July and 24 August's "Black Monday". By 8–9 July 2015, the Shanghai stock market had fallen 30 percent over three weeks as 1,400 companies, or more than half listed, filed for a trading halt in an attempt to prevent further losses. Values of Chinese stock markets continued to drop despite efforts by the government to reduce the fall. After three stable weeks the Shanghai index fell again on 24 August by 8.48 percent, marking the largest fall since 2007. At the October 2015 International Monetary Fund (IMF) annual meeting of "finance ministers and central bankers from the Washington-based lender’s 188 member-countries" held in Peru, China's slump dominated discussions with participants asking if "China’s economic downturn [would] trigger a new financial crisis". By the end of December 2015 China's stock market had recovered from the shocks and had outperformed S&P for 2015, though still well below the 12 June highs. By the end of 2015 the Shanghai Composite Index was up 12.6 percent. In January 2016 the Chinese stock market experienced a steep sell-off and trading was halted on 4 and 7 January 2016 after the market fell 7%, the latter within 30 minutes of open. The market meltdown set off a global rout in early 2016. According to 19 January 2016 articles in the Xinhua News Agency, the official press agency of the China , China reported a 6.9 percent GDP growth rate for 2015 and an "economic volume of over ten trillion U.S. dollars". Forbes journalist argues that the "stock market crash does not indicate a blowout of the Chinese physical economy." China is shifting from a focus on manufacturing to service industries and while it has slowed down, it is still growing by 5%. After this last turbulence, as of January 2017 the Shanghai Composite Index has been stable around 3,000 points, 50% less than before the bubble popped.
  • 6.0K
  • 28 Nov 2022
Topic Review
Metabolic N-Dealkylation and N-Oxidation
Metabolic reactions that occur at alkylamino moieties may provide insight into the roles of these moieties when they are parts of drug molecules that act at different receptors. N-dealkylation of N,N-dialkylamino moieties has been associated with retaining, attenuation or loss of pharmacologic activities of metabolites compared to their parent drugs. Further, N-dealkylation has resulted in clinically used drugs, activation of prodrugs, change of receptor selectivity, and providing potential for developing fully-fledged drugs.
  • 6.0K
  • 13 Apr 2021
Topic Review
Sallekhana
Sallekhana (IAST: sallekhanā), also known as Samlehna, Santhara, Samadhi-marana or Sanyasana-marana; is a supplementary vow to the ethical code of conduct of Jainism. It is the religious practice of voluntarily fasting to death by gradually reducing the intake of food and liquids. It is viewed in Jainism as the thinning of human passions and the body, and another means of destroying rebirth-influencing karma by withdrawing all physical and mental activities. It is not considered as a suicide by Jain scholars because it is not an act of passion, nor does it deploy poisons or weapons. After the sallekhana vow, the ritual preparation and practice can extend into years. Sallekhana is a vow available to both for Jain ascetics and householders. Historic evidence such as nishidhi engravings suggest sallekhana was observed by both men and women, including queens, in Jain history. However, in the modern era, death through sallekhana has been a relatively uncommon event. There is debate about the practice from a right to life and a freedom of religion viewpoint. In 2015, the Rajasthan High Court banned the practice, considering it suicide. Later that year, the Supreme Court of India stayed the decision of the Rajasthan High Court and lifted the ban on Sallekhana.
  • 6.0K
  • 10 Nov 2022
Topic Review
Location-Based Social Networks
There are several definitions for “geosocial network” or “location-based social network”: the first formal definition was given by Quercia et al. in 2010, who defined it as “a type of social networking in which geographic services and capabilities such as geocoding and geotagging are used to enable additional social dynamics”. One year later, Zheng refined this definition by stating that “a location-based social network (LBSN) does not only mean adding a location to an existing social network so that people in the social structure can share location embedded information but also consists of the new social structure made up of individuals connected by the interdependency derived from their locations in the physical world as well as their location-tagged media content, such as photos, video, and texts”. In 2013, Roick and Heuser defined LBSNs simply as “social network sites that include location information into shared contents”. Finally, one most recent definition is given by Armenatzoglou and Papadias and is the following: “geosocial network (GeoSN) is an online social network augmented by geographical information”.
  • 6.0K
  • 17 Jan 2022
Topic Review
Diagnosis and Management of Onychotillomania
Onychotillomania is defined as repetitive picking or pulling of the nail unit, causing damage to the nail matrix, nail bed, nail plate and/or periungual skin.
  • 6.0K
  • 23 Mar 2022
Topic Review
Agriculture Robotics
Agricultural robotics aims to overcome the challenges imposed by population growth, accelerated urbanization, high competitiveness of high-quality products, environmental preservation and a lack of qualified labor. The main existing applications of agricultural robotic systems are for the execution of land preparation before planting, sowing, planting, plant treatment, harvesting, yield estimation and phenotyping.
  • 6.0K
  • 05 May 2021
Topic Review
Different Types of Literature Review
Literature reviews are crucial for demonstrating progress and a comprehensive understanding of a subject. However, an unorganized growth in literature can lead to complicated and competing arguments, hindering progress. This research delves into different types of literature reviews and the common mistakes researchers make when conducting them. Learning how to efficiently conduct a literature review is essential for success in academia and professional careers.
  • 6.0K
  • 09 May 2023
Topic Review
Polyoxymethylene
Polyoxymethylene (POM) is a material able to provide tooth-colored esthetics and that is suitable for fabrication of frameworks for removable dental prostheses. POM can be characterized as both polyethers (-C-O-) as well as polyacetals (-O-C-O-).
  • 6.0K
  • 29 Apr 2021
Topic Review
Broadcasting
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began with AM radio, which came into popular use around 1920 with the spread of vacuum tube radio transmitters and receivers. Before this, all forms of electronic communication (early radio, telephone, and telegraph) were one-to-one, with the message intended for a single recipient. The term broadcasting evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as early as 1898. Over the air broadcasting is usually associated with radio and television, though more recently, both radio and television transmissions have begun to be distributed by cable (cable television). The receiving parties may include the general public or a relatively small subset; the point is that anyone with the appropriate receiving technology and equipment (e.g., a radio or television set) can receive the signal. The field of broadcasting includes both government-managed services such as public radio, community radio and public television, and private commercial radio and commercial television. The U.S. Code of Federal Regulations, title 47, part 97 defines "broadcasting" as "transmissions intended for reception by the general public, either direct or relayed". Private or two-way telecommunications transmissions do not qualify under this definition. For example, amateur ("ham") and citizens band (CB) radio operators are not allowed to broadcast. As defined, "transmitting" and "broadcasting" are not the same. Transmission of radio and television programs from a radio or television station to home receivers by radio waves is referred to as "over the air" (OTA) or terrestrial broadcasting and in most countries requires a broadcasting license. Transmissions using a wire or cable, like cable television (which also retransmits OTA stations with their consent), are also considered broadcasts but do not necessarily require a license (though in some countries, a license is required). In the 2000s, transmissions of television and radio programs via streaming digital technology have increasingly been referred to as broadcasting as well.
  • 6.0K
  • 24 Nov 2022
Topic Review
Waste Treatment Using Black Soldier Fly
Poor waste management has adverse impacts on the environment and human health. The recent years have seen increasing interest in using black soldier fly (BSF), Hermetia illucens, as an organic waste converter. Black soldier fly larvae (BSFL) feed voraciously on various types of organic waste, including food wastes, agro-industrial by-products, and chicken and dairy manure, and reduce the initial weight of the organic waste by about 50% in a shorter period than conventional composting. The main components of the BSFL system are the larvero, where the larvae feed and grow, and the fly house, where the adults BSF live and reproduce.
  • 6.0K
  • 28 Apr 2022
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