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Topic Review

Acid throwing, also called an acid attack, a vitriol attack or vitriolage, is a form of violent assault defined as the act of throwing acid or a similarly corrosive substance onto the body of another "with the intention to disfigure, maim, torture, or kill". Perpetrators of these attacks throw corrosive liquids at their victims, usually at their faces, burning them, and damaging skin tissue, often exposing and sometimes dissolving the bones. The most common types of acid used in these attacks are sulfuric and nitric acid. Hydrochloric acid is sometimes used, but is much less damaging. Aqueous solutions of strongly alkaline materials, such as caustic soda (sodium hydroxide), are used as well, particularly in areas where strong acids are controlled substances. The long term consequences of these attacks may include blindness, as well as permanent scarring of the face and body, along with far-reaching social, psychological, and economic difficulties. Today, acid attacks are reported in many parts of the world. Since the 1990s, Bangladesh has been reporting the highest number of attacks and highest incidence rates for women, with 3,512 Bangladeshi people acid attacked between 1999 and 2013, and in Pakistan and India acid attacks are at an all-time high and increasing every year. Although acid attacks occur all over the world, this type of violence is most common in South Asia. The UK has one of the highest rates of acid attacks per capita in the world, according to Acid Survivors Trust International (ASTI). In 2016 there were over 601 acid attacks in the UK based on ASTI figures. Over 1,200 cases were recorded over the past 5 years. From 2011 to 2016 there were 1,464 crimes involving acid or corrosive substance in London alone.

9.0K
21 Oct 2022

Topic Review

Atomic units (au or a.u.) form a system of natural units which is especially convenient for atomic physics calculations. There are two different kinds of atomic units, Hartree atomic units and Rydberg atomic units, which differ in the choice of the unit of mass and charge. This article deals with Hartree atomic units, where the numerical values of the following four fundamental physical constants are all unity by definition: In Hartree units, the speed of light is approximately [math]\displaystyle{ 137 }[/math]. Atomic units are often abbreviated "a.u." or "au", not to be confused with the same abbreviation used also for astronomical units, arbitrary units, and absorbance units in different contexts.

9.0K
10 Nov 2022

Biography

Deepak Chopra (/ˈdiːpɑːk ˈtʃoʊprə/; Hindi: [d̪iːpək tʃoːpraː]; born October 22, 1946) is an Indian-born American author and alternative-medicine advocate.[1][2] A prominent figure in the New Age movement,[3] his books and videos have made him one of the best-known and wealthiest figures in alternative medicine.[4] Chopra studied medicine in India before emigrating in 1970 to the

9.0K
05 Dec 2022

Topic Review

CASC Rainbow (Cai Hong, abbreviated as CH) is a series of unmanned aerial vehicles (UAVs) developed by the China Academy of Aerospace Aerodynamics, an entity under the China Aerospace Science and Technology Corporation (CASC). The China Academy of Aerospace Aerodynamics is also known as the 11th Academy of CASC, or 701st Research Institute.

9.0K
17 Oct 2022

Topic Review

Prime Video, also marketed as Amazon Prime Video, is an American Internet video on demand service that is developed, owned, and operated by Amazon. It offers television shows and films for rent or purchase and Prime Video, a selection of Amazon Studios original content and licensed acquisitions included in the Amazon's Prime subscription. In the United Kingdom , United States , Germany , and many other territories, access to Prime Video is also available through a video-only membership, which does not require a full Prime subscription. In France and Italy, and other countries like Australia , Canada , India , etc. Prime Video content is only accessible through a dedicated Prime Video website. In some countries Prime Video additionally offers Amazon Channels, which allows viewers to subscribe to other suppliers' content, including HBO in the United States. Launched on September 7, 2006 as Amazon Unbox in the United States, the service grew with its expanding library, and added the Prime Video membership with the development of Prime. It was then renamed as Amazon Instant Video on Demand. After acquiring the local streaming and DVD-by-mail service LoveFilm in 2011, Prime Video was added to Prime in the United Kingdom, Germany and Austria in 2014, a move that angered some Prime UK members as the bundling was non-negotiable with a 61% increase in subscription fee. In the UK, Germany, and Austria, Prime Video has been available on a monthly subscription of £5.99 or €7.99 per month, continuing the plan of LoveFilm Instant. The service was previously available in Norway , Denmark and Sweden in 2012, but was discontinued in 2013. On April 18, 2016, Amazon split Prime Video from Amazon Prime in the US for $8.99 per month. The service also hosts Amazon Original content alongside titles on Video as well. On December 14, 2016, Prime Video launched worldwide (except for Mainland China, Cuba, Iran, North Korea, Syria) expanding its reach beyond the US, the UK, Germany, Austria, and Japan. Among the new territories, the service was included with Prime in Belgium, Canada , France , India , Italy, Spain , Poland , and Brazil , while for all other countries – for instance Bulgaria – it was made available for a monthly promotional price of $/€2.99 per month for the first six months and $/€5.99 per month thereafter.

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29 Nov 2022

Topic Review

Pigmentary and Structural Coloration in Nature

Most of us get inspired by and interact with the world around us based on visual cues such as the colors and patterns that we see. In nature, coloration takes three primary forms: pigmentary coloration, structural coloration, and bioluminescence. Typically, pigmentary and structural coloration are used by animals and plants for their survival. These forms of coloration are enabled by a variety of intracellular biophotonic structures.

9.0K
09 Jun 2022

Topic Review

Devil in Christianity

The Devil in Christianity is the personification of evil and author of sin, who rebelled against God in an attempt to become equal to God himself.[lower-alpha 1] He is depicted as a fallen angel, who was expelled from Heaven at the beginning of time, before God created the material world, and is in constant opposition to God. The devil is identified with several figures in the Bible including the serpent in the Garden of Eden, Lucifer, Satan, the tempter of the Gospels, Leviathan, and the dragon in the Book of Revelation. Early scholars discussed the role of the devil. Scholars influenced by neoplatonic cosmology, like Origen and Pseudo-Dionysius, portrayed the devil as representing deficiency and emptiness, the entity most remote from the divine. According to Augustine of Hippo the realm of the devil is not nothingness, but an inferior realm standing in opposition to God. The standard Medieval depiction of the devil was set up by Gregory the Great. He integrated the devil, as the first creation of God, into the Christian angelic hierarchy as the highest of the angels (either a cherub or a seraph). But as high as he stood in heaven, so far he fell into the depths of hell and became the leader of demons. Since the early reformation period, the devil was imagined as an increasingly powerful entity, with not only a lack of goodness but also a conscious will against God, his word, and his creation. Simultaneously, some reformists interpreted the devil as a mere metaphor for human's inclination to sin and so downgraded the importance of the devil. While the devil played for most scholars no significant role in the Modern Era, he became more important in contemporary Christianity again. At various times in history, some people such as the Cathars and the Bogomiles, as well as theologians like Marcion and Valentinus, believed that the devil was involved in creating the world. Today these views are not part of mainstream Christianity.

9.0K
06 Dec 2022

Topic Review

Remarriage is a marriage that takes place after a previous marital union has ended, as through divorce or widowhood. Some individuals are more likely to remarry than others; the likelihood can differ based on previous relationship status (e.g. divorced vs. widowed), level of interest in establishing a new romantic relationship, gender, race, and age among other factors. Those who choose not to remarry may prefer alternative arrangements like cohabitation or living apart together. Remarriage also provides mental and physical health benefits. However, although remarried individuals tend to have better health than individuals who do not repartner, they still generally have worse health than individuals who have remained continuously married. Someone who repeatedly remarries is referred to as a serial wedder.

9.0K
27 Oct 2022

Topic Review

History of Zoology (Through 1859)

The history of zoology before Charles Darwin's 1859 theory of evolution traces the organized study of the animal kingdom from ancient to modern times. Although the concept of zoology as a single coherent field arose much later, systematic study of zoology is seen in the works of Aristotle and Galen in the ancient Greco-Roman world. This work was developed in the Middle Ages by Islamic medicine and scholarship, and in turn their work was extended by European scholars such as Albertus Magnus. During the European Renaissance and early modern period, zoological thought was revolutionized in Europe by a renewed interest in empiricism and the discovery of many novel organisms. Prominent in this movement were the anatomist Vesalius and the physiologist William Harvey, who used experimentation and careful observation, and naturalists such as Carl Linnaeus and Buffon who began to classify the diversity of life and the fossil record, as well as the development and behavior of organisms. Microscopy revealed the previously unknown world of microorganisms, laying the groundwork for cell theory. The growing importance of natural theology, partly a response to the rise of mechanical philosophy, encouraged the growth of natural history (although it entrenched the argument from design). Over the 18th and 19th centuries, zoology became increasingly professional scientific disciplines. Explorer-naturalists such as Alexander von Humboldt investigated the interaction between organisms and their environment, and the ways this relationship depends on geography—laying the foundations for biogeography, ecology and ethology. Naturalists began to reject essentialism and consider the importance of extinction and the mutability of species. Cell theory provided a new perspective on the fundamental basis of life. These developments, as well as the results from embryology and paleontology, were synthesized in Charles Darwin's theory of evolution by natural selection. In 1859, Darwin placed the theory of organic evolution on a new footing, by his discovery of a process by which organic evolution can occur, and provided observational evidence that it had done so.

9.0K
21 Apr 2023

Topic Review

Stall (Fluid Mechanics)

In fluid dynamics, a stall is a reduction in the lift coefficient generated by a foil as angle of attack increases. This occurs when the critical angle of attack of the foil is exceeded. The critical angle of attack is typically about 15 degrees, but it may vary significantly depending on the fluid, foil, and Reynolds number. Stalls in fixed-wing flight are often experienced as a sudden reduction in lift as the pilot increases the wing's angle of attack and exceeds its critical angle of attack (which may be due to slowing down below stall speed in level flight). A stall does not mean that the engine(s) have stopped working, or that the aircraft has stopped moving—the effect is the same even in an unpowered glider aircraft. Vectored thrust in manned and unmanned aircraft is used to surpass the stall limit, thereby giving rise to post-stall technology. Because stalls are most commonly discussed in connection with aviation, this article discusses stalls as they relate mainly to aircraft, in particular fixed-wing aircraft. The principles of stall discussed here translate to foils in other fluids as well.

9.0K
16 Nov 2022

Topic Review

Religious Studies

Religious studies, alternately known as the study of religion, is an academic field devoted to research into religious beliefs, behaviors, and institutions. It describes, compares, interprets, and explains religion, emphasizing systematic, historically based, and cross-cultural perspectives. While theology attempts to understand the nature of transcendent or supernatural forces (such as deities), religious studies tries to study religious behavior and belief from outside any particular religious viewpoint. Religious studies draws upon multiple disciplines and their methodologies including anthropology, sociology, psychology, philosophy, and history of religion. Religious studies originated in the 19th century, when scholarly and historical analysis of the Bible had flourished, and Hindu and Buddhist texts were first being translated into European languages. Early influential scholars included Friedrich Max Müller, in England, and Cornelius P. Tiele, in the Netherlands. Today religious studies is practiced by scholars worldwide. In its early years, it was known as Comparative Religion or the Science of Religion and, in the USA, there are those who today also know the field as the History of religion (associated with methodological traditions traced to the University of Chicago in general, and in particular Mircea Eliade, from the late 1950s through to the late 1980s). The term "religion" originated from the Latin noun "religio", that was nominalized from one of three verbs: "relegere" (to turn to constantly/observe conscientiously); "religare" (to bind oneself [back]); and "reeligere" (to choose again). Because of these three different potential meanings, an etymological analysis alone does not resolve the ambiguity of defining religion, since each verb points to a different understanding of what religion is. During the Medieval Period, the term "religious" was used as a noun to describe someone who had joined a monastic order (a "religious"). The religious studies scholar Walter Capps described the purpose of the discipline as to provide "training and practice... in directing and conducting inquiry regarding the subject of religion". At the same time, Capps stated that its other purpose was to use "prescribed modes and techniques of inquiry to make the subject of religion intelligible." Religious studies scholar Robert A. Segal characterised the discipline as "a subject matter" that is "open to many approaches", and thus it "does not require either a distinctive method or a distinctive explanation to be worthy of disciplinary status." Different scholars operating in the field have different interests and intentions; some for instance seek to defend religion, while others seek to explain it away, and others wish to use religion as an example with which to prove a theory of their own. Some scholars of religious studies are interested in primarily studying the religion to which they belong. Scholars of religion have argued that a study of the subject is useful for individuals because it will provide them with knowledge that is pertinent in inter-personal and professional contexts within an increasingly globalised world. It has also been argued that studying religion is useful in appreciating and understanding sectarian tensions and religious violence.

9.0K
22 Nov 2022

Topic Review

Sub Synchronous Oscillation Phenomenon

The definition of sub synchronous oscillation (SSO) according to the IEEE Sub Synchronous Resonance Working Group is as follows. “Sub synchronous oscillation is an electric power system condition where the electric network exchanges significant energy with a turbine generator at one or more of the natural frequencies of the combined system below the synchronous frequency of the system following a disturbance from equilibrium”. According to the classification of SSO by the IEEE Sub Synchronous Resonance Working Group, there are two types of SSO, namely sub synchronous resonance (SSR) and device dependent sub synchronous oscillation (DDSSO). Sub synchronous control interaction (SSCI) and sub synchronous torsional interaction (SSTI) are other types of SSO. However, they are not included in the formal classification.

9.0K
09 Dec 2022

Topic Review

Trickle-Down Economics

Trickle-down economics, also called trickle-down theory, refers to the economic proposition that taxes on businesses and the wealthy in society should be reduced as a means to stimulate business investment in the short term and benefit society at large in the long term. In recent history, the term has been used by critics of supply-side economic policies, such as "Reaganomics". Whereas general supply-side theory favors lowering taxes overall, trickle-down theory more specifically targets taxes on the upper end of the economic spectrum. The term "trickle-down" originated as a joke by humorist Will Rogers and today is often used to criticize economic policies that favor the wealthy or privileged while being framed as good for the average citizen. David Stockman, who as Ronald Reagan's budget director championed Reagan's tax cuts at first, later became critical of them and told journalist William Greider that "supply-side economics" is the trickle-down idea: Political opponents of the Reagan administration soon seized on this language in an effort to brand the administration as caring only about the wealthy. Some studies suggest a link between trickle-down economics and reduced growth. Trickle-down economics has been widely criticized, particularly by left-wing, centre-left and moderate politicians and economists, but also some right-wing politicians. A 2019 study in the Journal of Political Economy found, contrary to trickle-down theory, that "the positive relationship between tax cuts and employment growth is largely driven by tax cuts for lower-income groups and that the effect of tax cuts for the top 10 percent on employment growth is small."

9.0K
02 Dec 2022

Biography

Hindemburg Melão Jr.

Hindemburg Melão Jr. (born 15 January 1972, in São Paulo) is a Brazilian philosopher, investor, epistemologist, theologian, author, retired chess player, amateur astrophotographer, and science popularizer.[1] Hindemburg has written over 1600 articles on science, philosophy, chess, finance, among other fields, and the book IMC na Balança ("BMI on the scale"). Hindemburg is known as a player o

9.0K
12 Dec 2022

Topic Review Peer Reviewed

Challenges for Nanotechnology

The term “Nanotechnology” describes a large field of scientific and technical activities dealing with objects and technical components with small dimensions. Typically, bodies that are in–at least–two dimensions smaller than 0.1 µm are regarded as “nanobjects”. By this definition, a lot of advanced materials, as well as the advanced electronic devices, are objects of nanotechnology. In addition, many aspects of molecular biotechnology as well as macromolecular and supermolecular chemistry and nanoparticle techniques are summarized under “nanotechnology”. Despite this size-oriented definition, nanotechnology is dealing with physics and chemistry as well as with the realization of technical functions in the area between very small bodies and single particles and molecules. This includes the shift from classical physics into the quantum world of small molecules and low numbers or single elementary particles. Besides the already established fields of nanotechnology, there is a big expectation about technical progress and solution to essential economic, medical, and ecological problems by means of nanotechnology. Nanotechnology can only meet these expectations if fundamental progress behind the recent state of the art can be achieved. Therefore, very important challenges for nanotechnology are discussed here.

8.9K
13 Apr 2022

Topic Review

Aarne–Thompson Classification Systems

The Aarne–Thompson classification systems are indices used to classify folktales: the Aarne–Thompson Motif-Index (catalogued by alphabetical letters followed by numerals), the Aarne–Thompson Tale Type Index (cataloged by AT or AaTh numbers), and the Aarne–Thompson–Uther classification system (developed in 2004 and cataloged by ATU numbers). They are named after their authors, Antti Aarne, Stith Thompson, and Hans-Jörg Uther. The indices are used in folkloristics to organize, classify, and analyze folklore narratives and are essential tools for folklorists, as Alan Dundes explained in 1997 about the first two indices, "the identification of folk narratives through motif and/or tale type numbers has become an international sine qua non among bona fide folklorists".

8.9K
05 Dec 2022

Topic Review

The Nag missile (IAST: Nāga; en: Cobra), also called "Prospina" for the land-attack version, is an India n third-generation, all-weather, fire-and-forget, lock-on after launch, anti-tank guided missile (ATGM) with an operational range of 500 m to 20 km. It has a single-shot hit probability of 90% and a ten-year, maintenance-free shelf life. The Nag has five variants under development: a land version, for a mast-mounted system; the helicopter-launched Nag (HELINA) also known as Dhruvastra; a "man-portable" version (MPATGM); an air-launched version which will replace the current imaging infra-red (IIR) to millimetric-wave (mmW) active radar homing seeker; and the Nag Missile Carrier (NAMICA) "tank buster", which is a modified BMP-2 Infantry Fighting Vehicle (IFV) produced under license in India by Ordnance Factory Medak (OFMK). Development of the Nag is part of the Integrated Guided Missile Development Program (IGMDP), run by Defence Research and Development Organisation (DRDO). It is manufactured by Bharat Dynamics Limited (BDL). India's Ministry of Defence (MoD) announced on 19 July 2019 that the missile was ready for production. The Defence Research and Development Organization (DRDO) successfully completed the final trial of Nag anti-tank missile using a live warhead on a dud tank at Pokhran army ranges at 6.45 am on Oct 21, 2020.

8.9K
09 Oct 2022

Topic Review

Anthroponotic Disease

Reverse zoonosis, also known as zooanthroponosis, and sometimes anthroponosis (Greek zoon "animal", anthropos "man", nosos "disease"), refers to pathogens reservoired in humans that are capable of being transmitted to other non-human animals.

8.9K
28 Oct 2022

Topic Review

Transwiki: Multiregional Origin of Modern Humans

The multiregional hypothesis is a scientific model that provides an explanation for the pattern of human evolution. The hypothesis holds that humans first arose near the beginning of the Pleistocene two million years ago and subsequent human evolution has been within a single, continuous human species. This species encompasses archaic human forms such as Homo erectus and Neanderthals as well as modern forms, and evolved worldwide to the diverse populations of modern Homo sapiens sapiens. The theory contends that humans evolve through a combination of adaptation within various regions of the world and gene flow between those regions. Proponents of multiregional origin point to fossil and genomic data and continuity of archaeological cultures as support for their hypothesis. The primary alternative hypothesis is recent African origin of modern humans, which contends that modern humans arose in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace archaic human forms without interbreeding.

8.9K
11 Nov 2022

Topic Review

Mass media refers to a diverse range of communication channels that transmit information and entertainment content to a large audience. This encompasses traditional mediums such as newspapers, television, and radio, as well as modern digital platforms like the internet and social media. Mass media plays a crucial role in shaping public opinion, disseminating news, and influencing societal norms on a global scale.

8.9K
25 Jan 2024

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