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Topic Review
Iron-Containing Oral Contraceptives
Oral contraceptive use has been associated with decreased menstrual blood losses; thus, can independently reduce the risk of anemia and iron deficiency in women. Manufacturers have recently started to include supplemental iron in the non-hormonal placebo tablets of some contraceptives. 
  • 9.6K
  • 15 Jul 2021
Topic Review
Rheinmetall 120 Mm Gun
The Rheinmetall 120 mm gun is a smoothbore tank gun designed and produced by the West German Rheinmetall-DeTec AG company, developed in response to Soviet advances in armor technology and development of new armored threats. Production began in 1974, with the first version of the gun, known as the L/44 as it was 44 calibers long, used on the German Leopard 2 tank and soon produced under license for the American M1A1 Abrams and other tanks. The American version, the M256, uses a coil spring recoil system instead of a hydraulic system. The 120-millimeter (4.7 in) gun has a length of 5.28 meters (17.3 ft), and the gun system weighs approximately 3,317 kilograms (7,313 lb). By 1990, the L/44 was not considered powerful enough to deal with future Soviet armour, which stimulated an effort by Rheinmetall to develop a better main armament. This first involved a 140-millimeter (5.5 in) tank gun named Neue Panzerkanone 140 ("new tank gun 140"), but later turned into a compromise which led to the development of an advanced 120 mm gun, the L/55, based on the same internal geometry as the L/44 and installed in the same breech and mount. The L/55 is 1.32 meters (4.3 ft) longer, giving increased muzzle velocity to ammunition fired through it. As the L/55 retains the same barrel geometry, it can fire the same ammunition as the L/44. This gun was retrofitted into German and Dutch Leopard 2s, and chosen as the main gun of the Spanish Leopard 2E and the Greek Leopard 2HEL. It was tested on the British Challenger 2 as a potential replacement for its current weapon, the rifled L30 120 mm cannon. A variety of ammunition has been developed for use by tanks with guns based on Rheinmetall's original L/44 design. This includes a series of kinetic energy penetrators, such as the American M829 series, and high explosive anti-tank warheads. Recent ammunition includes a range of anti-personnel rounds and demolition munitions. The LAHAT, developed in Israel, is a gun-launched missile which has received interest from Germany and other Leopard 2 users, and is designed to defeat both land armour and combat helicopters. The Israelis also introduced a new anti-personnel munition which limits collateral damage by controlling the fragmentation of the projectile.
  • 9.6K
  • 27 Oct 2022
Topic Review
Control Techniques in Photovoltaic Systems
Complex control structures are required for the operation of photovoltaic electrical energy systems. In this paper, a general review of the controllers used for photovoltaic systems is presented. This entry is based on the most recent papers presented in the literature. The control architectures considered are complex hybrid systems that combine classical and modern techniques, such as artificial intelligence and statistical models. The main contribution of this paper is the synthesis of a generalized control structure and the identification of the latest trends. The main findings are summarized in the development of increasingly robust controllers for operation with improved efficiency, power quality, stability, safety, and economics.
  • 9.6K
  • 19 Feb 2021
Topic Review
Harrison Family of Virginia
The Harrison family of Virginia, primarily consisting of two branches, is a notable political family in U.S. history. The family’s origin is in England ; members of one branch immigrated to Virginia before 1633, settled on the James River, and are occasionally referred to as the James River Harrisons. This branch includes successive generations who served in the colonial Virginia legislature, a signer of the Declaration of Independence, and several Virginia Governors. Also notably descended from the James River family were two presidents of the United States, William Henry Harrison and Benjamin Harrison. The family produced as well two mayors of Chicago, and members of the U. S. House of Representatives. The second branch of the Virginia Harrisons descends from an interim chaplain of the Jamestown Colony, who returned to England. The family later immigrated in 1687, first to New England, and then settled in the Shenandoah Valley of Virginia fifty years later. They include the founder of the city of Harrisonburg, and brought forth another of the nation’s presidents, Abraham Lincoln. This branch also includes noted physicians, educators, and local officials.
  • 9.6K
  • 27 Nov 2022
Topic Review
CNBC Ticker
The CNBC Ticker is a computer simulation of ticker tapes used by the United States business news-oriented television network CNBC (as well as its international sister channels), that is displayed as a crawl on the lower part of the television screen. The CNBC Ticker shows security and index symbols in the manner of the ticker tapes that received information by telegraph. The security identifiers used on the CNBC Ticker are taken from nomenclatures used by third-party companies like Reuters or from global stock exchanges. The ticker is composed of a faster-scrolling upper band with a white background and a slower-scrolling lower band with a dark blue background for all CNBC channels. In addition for some channels, such as CNBC Europe; CNBC-e; CNBC Arabiya and Class CNBC, a third business news band is displayed in gray with a black background. The ticker is shown throughout the duration of financial news programming on CNBC's domestic and international channels, including national commercial breaks. However, in the United States and Canada , advertisements that are locally inserted by cable television providers may be shown full-screen, omitting the ticker from being displayed during local breaks (as of 2013, all ad inserts by cable television providers, as well as satellite television providers DirecTV and Dish Network are now shown full-screen).
  • 9.6K
  • 18 Oct 2022
Topic Review
Luminiferous Aether
Luminiferous aether or ether ("luminiferous", meaning "light-bearing") was the postulated medium for the propagation of light. It was invoked to explain the ability of the apparently wave-based light to propagate through empty space, something that waves should not be able to do. The assumption of a spatial plenum of luminiferous aether, rather than a spatial vacuum, provided the theoretical medium that was required by wave theories of light. The aether hypothesis was the topic of considerable debate throughout its history, as it required the existence of an invisible and infinite material with no interaction with physical objects. As the nature of light was explored, especially in the 19th century, the physical qualities required of an aether became increasingly contradictory. By the late 1800s, the existence of the aether was being questioned, although there was no physical theory to replace it. The negative outcome of the Michelson–Morley experiment (1887) suggested that the aether did not exist, a finding that was confirmed in subsequent experiments through the 1920s. This led to considerable theoretical work to explain the propagation of light without an aether. A major breakthrough was the theory of relativity, which could explain why the experiment failed to see aether, but was more broadly interpreted to suggest that it was not needed. The Michelson-Morley experiment, along with the blackbody radiator and photoelectric effect, was a key experiment in the development of modern physics, which includes both relativity and quantum theory, the latter of which explains the particle-like nature of light.
  • 9.6K
  • 17 Oct 2022
Topic Review
Islam and Secularism
Secularism—i.e. the separation of religion from civic affairs and the state—has been a controversial concept in Islamic political thought, owing in part to historical factors and in part to the ambiguity of the concept itself. In the Muslim world, the notion has acquired strong negative connotations due to its association with removal of Islamic influences from the legal and political spheres under foreign colonial domination, as well as attempts to restrict public religious expression by some secularist nation states. Thus, secularism has often been perceived as a foreign ideology imposed by invaders and perpetuated by post-colonial ruling elites, and is frequently understood to be equivalent to irreligion or anti-religion. Especially in the late 19th to mid-20th century, some Muslim thinkers advocated secularism as a way to strengthen the Islamic world in the face of Russian, British and French colonialism. Some have advocated secularism in the sense of political order that does not impose any single interpretation of sharia (Ali Abdel Raziq and Mahmoud Mohammed Taha); argued that such a political order would not/does not violate Islam (Abdullah Saeed); and that combined with constitutionalism and human rights, is more consistent with Islamic history than modern visions of an Islamic state (Abdullahi Ahmed An-Na'im). Strongly opposed to limiting Islam to matters of personal belief, and strongly advocating an Islam encompassing law, politics, economics, culture and every other aspect of the lives of its citizens, are orthodox Islamic scholars and proponents of Islamism (political Islam). Islamist pioneer Abul A'la Maududi claimed that the goal of secularists was not to ameliorate tensions and divisions in multi-religious societies, but to avoid the "restraints of morality and divine guidance", and thus eliminate "all morality, ethics, or human decency from the controlling mechanisms of society." A number of pre-modern polities in the Islamic world demonstrated some level of separation between religious and political authority, even if they did not adhere to the modern concept of a state with no official religion or religion-based laws. Today, some Muslim-majority countries define themselves as or are regarded as secular. Many of them have a dual legal system in which Muslims can bring familial and financial disputes to sharia courts whose jurisdiction varies from country to country but usually includes marriage, divorce, inheritance, and guardianship.
  • 9.6K
  • 26 Oct 2022
Topic Review
GURUKUL: The Schools of Ancient India
"GURUKUL" a combination of the Sanskrit words Guru(Teacher) and Kula(Home or Family) which literally means "Home of the Guru". This research talks about the Gurukuls of Ancient India, the education system of our own India which was demolished by the Britishers.
  • 9.6K
  • 29 Apr 2024
Topic Review
Inelastic Neutron Scattering
Inelastic neutron scattering (INS) is a spectroscopy based on the energy analysis of neutrons after they have been scattered by a sample. A detected energy transfer can be related to a physical interaction of the corresponding atoms with their environment. An energy transfer of several meVs typically arises from vibrations of atoms. Thus, INS provides an amplitude-of-motion and neutron incoherent cross section weighted phonon density of states.  Given the much higher incoherent scattering cross section of hydrogen relative to that of all other elements, INS is particular sensitive to hydrogen based vibrations. The method is widely used in condensed matter physics and solid state chemistry, because the vibrational properties of matter define various physical properties such as the heat capacity. If used as a fingerprint method, INS can be used to characterize chemical bonds both in the bulk as well as on the surface.
  • 9.6K
  • 30 Oct 2020
Topic Review
Irreligion in India
Atheism and agnosticism have a long history in India and flourished within the Śramaṇa movement. Indian religions like Jainism, Hinduism and Buddhism consider atheism to be acceptable. India has produced some notable atheist politicians and social reformers. According to the 2011 Census of India, 99.76% of Indians identified with a religion while 0.24% did not state their religious identity. According to the 2012 WIN-Gallup Global Index of Religion and Atheism report, 81% of Indians were religious, 13% were non-religious, 3% were convinced atheists, and 3% were unsure or did not respond.
  • 9.6K
  • 09 Oct 2022
Topic Review
Stilbene Biosynthesis
Stilbenes are a small family of polyphenolic secondary metabolites that can be found in several distantly related plant species. These compounds act as phytoalexins, playing a crucial role in plant defense against phytopathogens, as well as being involved in the adaptation of plants to abiotic environmental factors. Among stilbenes, trans-resveratrol is certainly the most popular and extensively studied for its health properties. However, many other stilbenes, both monomeric and oligomeric, are currently under intensive investigation due to their biological role and bioactivity.
  • 9.6K
  • 14 Jan 2021
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.
  • 9.6K
  • 21 Apr 2023
Topic Review
Ascomycota
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defining feature of this fungal group is the "ascus" (from grc ἀσκός (askós) 'sac, wineskin'), a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens (loosely termed "ascolichens") such as Cladonia belong to the Ascomycota. Ascomycota is a monophyletic group (it contains all descendants of one common ancestor). Previously placed in the Deuteromycota along with asexual species from other fungal taxa, asexual (or anamorphic) ascomycetes are now identified and classified based on morphological or physiological similarities to ascus-bearing taxa, and by phylogenetic analyses of DNA sequences. The ascomycetes are of particular use to humans as sources of medicinally important compounds, such as antibiotics, for fermenting bread, alcoholic beverages and cheese. Penicillium species on cheeses and those producing antibiotics for treating bacterial infectious diseases are examples of ascomycetes. Many ascomycetes are pathogens, both of animals, including humans, and of plants. Examples of ascomycetes that can cause infections in humans include Candida albicans, Aspergillus niger and several tens of species that cause skin infections. The many plant-pathogenic ascomycetes include apple scab, rice blast, the ergot fungi, black knot, and the powdery mildews. Several species of ascomycetes are biological model organisms in laboratory research. Most famously, Neurospora crassa, several species of yeasts, and Aspergillus species are used in many genetics and cell biology studies.
  • 9.6K
  • 04 Nov 2022
Topic Review
Emulsion Gel and Its Preparation
Emulsion gels are emulsion with a gel network structure and stable mechanical properties. Emulsion gel formation is considered a strategy for oil stabilization and structuring, presenting advantages such as transporting functional components and improving the sensory and physical product properties. 
  • 9.5K
  • 15 Jul 2022
Topic Review
Cocoa Shell
The positive impact of cocoa shell on nutritional value of food was emphasized, such as increase of fiber content, enrichment with polyphenols, positive impact on glucose metabolism. However, potential shortcomings, such as mycotoxins, PAHs, and microbial contamination are also discussed.
  • 9.5K
  • 28 Oct 2020
Topic Review
Co-Culture System
Co-culture system provides a novel platform to study interaction between different cell types in an in-vitro method. The co-cultures techniques have played key role in the understanding of cell–cell communication and relevant for drug response analysis. 
  • 9.5K
  • 21 Jan 2021
Biography
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell OM FRS[1] (18 May 1872 – 2 February 1970) was a British polymath. As an academic, he worked in philosophy, mathematics, and logic. His work has had a considerable influence on mathematics, logic, set theory, linguistics, artificial intelligence, cognitive science, computer science, and various areas of analytic philosophy, especially philosophy
  • 9.5K
  • 18 Nov 2022
Topic Review
Evolutionary Psychology Controversy
The purpose of this article is to outline the various criticisms of evolutionary psychology, as well as counterarguments to these criticisms.
  • 9.5K
  • 08 Oct 2022
Topic Review
Synesthesia
Synesthesia (American English) or synaesthesia (British English) is a perceptual phenomenon in which stimulation of one sensory or cognitive pathway leads to involuntary experiences in a second sensory or cognitive pathway. People who report a lifelong history of such experiences are known as synesthetes. Awareness of synesthetic perceptions varies from person to person. In one common form of synesthesia, known as grapheme–color synesthesia or color–graphemic synesthesia, letters or numbers are perceived as inherently colored. In spatial-sequence, or number form synesthesia, numbers, months of the year, or days of the week elicit precise locations in space (e.g., 1980 may be "farther away" than 1990), or may appear as a three-dimensional map (clockwise or counterclockwise). Synesthetic associations can occur in any combination and any number of senses or cognitive pathways. Little is known about how synesthesia develops. It has been suggested that synesthesia develops during childhood when children are intensively engaged with abstract concepts for the first time. This hypothesis – referred to as semantic vacuum hypothesis – could explain why the most common forms of synesthesia are grapheme–color, spatial sequence, and number form. These are usually the first abstract concepts that educational systems require children to learn. Difficulties have been recognized in adequately defining synesthesia. Many different phenomena have been included in the term synesthesia, and in many cases the terminology seems to be inaccurate. A more accurate but less common term may be ideasthesia. The earliest recorded case of synesthesia is attributed to the Oxford University academic and philosopher John Locke, who, in 1690, made a report about a blind man who said he experienced the color scarlet when he heard the sound of a trumpet. However, there is disagreement as to whether Locke described an actual instance of synesthesia or was using a metaphor. The first medical account came from German physician Georg Tobias Ludwig Sachs in 1812. The term is from the Ancient Greek σύν syn, 'together', and αἴσθησις aisthēsis, 'sensation'.
  • 9.5K
  • 15 Nov 2022
Topic Review
Unbiunium
Check temperatures Ubu: no input for C, K, F. Check temperatures Ubu: no input for C, K, F. Unbiunium, also known as eka-actinium or simply element 121, is the hypothetical chemical element with symbol Ubu and atomic number 121. Unbiunium and Ubu are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to be the first of the superactinides, and the third element in the eighth period: analogously to lanthanum and actinium, it could be considered the fifth member of group 3 and the first member of the fifth-row transition metals. It has attracted attention because of some predictions that it may be in the island of stability, although newer calculations expect the island to actually occur at a slightly lower atomic number, closer to copernicium and flerovium. Unbiunium has not yet been synthesized. Nevertheless, because it is only three elements away from the heaviest known element, oganesson (element 118), its synthesis may come in the near future; it is expected to be one of the last few reachable elements with current technology, and the limit may be anywhere between element 120 and 124. It will also likely be far more difficult to synthesize than the elements known so far up to 118, and still more difficult than elements 119 and 120. The team at RIKEN in Japan has plans to attempt the synthesis of element 121 in the future after its attempts on elements 119 and 120. The position of unbiunium in the periodic table suggests that it would have similar properties to its lighter congeners, scandium, yttrium, lanthanum, and actinium; however, relativistic effects may cause some of its properties to differ from those expected from a straight application of periodic trends. For example, unbiunium is expected to have a s2p valence electron configuration instead of the s2d of its lighter congeners in group 3, but this is not expected to significantly affect its chemistry, which is predicted to be that of a normal group 3 element; it would on the other hand significantly lower its first ionisation energy beyond what would be expected from periodic trends.
  • 9.5K
  • 25 Oct 2022
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