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Topic Review
Water-Related Issues in Bhutan
Water for hydropower in Bhutan has been in focus as compared to that allocated for irrigation, industries, and environmental demand. The demand for water in Bhutan has also increased in the last decade due to population increase, changes in lifestyle, and economic advancements through tourism and hydropower projects.
  • 5.5K
  • 28 Apr 2021
Topic Review
Tomatine
Tomatine (sometimes called tomatin or lycopersicin) is a glycoalkaloid, found in the stems and leaves of tomato plants, and in the fruits at much lower concentrations. Chemically pure tomatine is a white crystalline solid at standard temperature and pressure. Tomatine is sometimes confused with the glycoalkaloid solanine, which is found in potatoes.
  • 5.5K
  • 26 Oct 2022
Biography
Ravidas
Ravidas was an India n mystic poet-sant of the Bhakti movement of Sri Hari and his incarnations like Rama, Krishna such as Namdev, Meerabai and founder of Ravidassia sect during the 15th to 16th century CE.[1][2] Venerated as a guru (teacher) in the region of Uttar Pradesh, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh and mainly Punjab and Haryana. He was a poet-saint, social reformer and a s
  • 5.5K
  • 15 Nov 2022
Topic Review
Turing Reduction
In computability theory, a Turing reduction from a problem A to a problem B, is a reduction which solves A, assuming the solution to B is already known (Rogers 1967, Soare 1987). It can be understood as an algorithm that could be used to solve A if it had available to it a subroutine for solving B. More formally, a Turing reduction is a function computable by an oracle machine with an oracle for B. Turing reductions can be applied to both decision problems and function problems. If a Turing reduction of A to B exists then every algorithm for B can be used to produce an algorithm for A, by inserting the algorithm for B at each place where the oracle machine computing A queries the oracle for B. However, because the oracle machine may query the oracle a large number of times, the resulting algorithm may require more time asymptotically than either the algorithm for B or the oracle machine computing A, and may require as much space as both together. The first formal definition of relative computability, then called relative reducibility, was given by Alan Turing in 1939 in terms of oracle machines. Later in 1943 and 1952 Stephen Kleene defined an equivalent concept in terms of recursive functions. In 1944 Emil Post used the term "Turing reducibility" to refer to the concept. A polynomial-time Turing reduction is known as a Cook reduction, after Stephen Cook.
  • 5.5K
  • 14 Oct 2022
Topic Review
Passivation
Passivation, in physical chemistry and engineering, refers to coating a material so it becomes "passive", that is, less readily affected or corroded by the environment. Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build by spontaneous oxidation in the air. As a technique, passivation is the use of a light coat of a protective material, such as metal oxide, to create a shield against corrosion. Passivation of silicon is used during fabrication of microelectronic devices. In electrochemical treatment of water, passivation reduces the effectiveness of the treatment by increasing the circuit resistance, and active measures are typically used to overcome this effect, the most common being polarity reversal, which results in limited rejection of the fouling layer.[clarification needed] When exposed to air, many metals naturally form a hard, relatively inert surface layer, usually an oxide (termed the "native oxide layer") or a nitride, that serves as a passivation layer. In the case of silver, the dark tarnish is a passivation layer of silver sulfide formed from reaction with environmental hydrogen sulfide. (In contrast, metals such as iron oxidize readily to form a rough porous coating of rust that adheres loosely and sloughs off readily, allowing further oxidation.) The passivation layer of oxide markedly slows further oxidation and corrosion in room-temperature air for aluminium, beryllium, chromium, zinc, titanium, and silicon (a metalloid). The inert surface layer formed by reaction with air has a thickness of about 1.5 nm for silicon, 1–10 nm for beryllium, and 1 nm initially for titanium, growing to 25 nm after several years. Similarly, for aluminium, it grows to about 5 nm after several years. Surface passivation refers to a common semiconductor device fabrication process critical to modern electronics. It is the process by which a semiconductor surface such as silicon is rendered inert, and does not change semiconductor properties when it interacts with air or other materials. This is typically achieved by thermal oxidation, in which the material is heated and exposed to oxygen. In a silicon semiconductor, this process allows electricity to reliably penetrate to the conducting silicon below the surface, and to overcome the surface states that prevent electricity from reaching the semiconducting layer. Surface passivation by thermal oxidation is one of the key features of silicon technology, and is dominant in microelectronics. The surface passivation process was developed by Mohamed M. Atalla at Bell Labs in the late 1950s. It is commonly used to manufacture MOSFETs (metal-oxide-semiconductor field-effect transistors) and silicon integrated circuit chips (with the planar process), and is critical to the semiconductor industry. Surface passivation is also critical to solar cell and carbon quantum dot technologies.
  • 5.5K
  • 03 Nov 2022
Topic Review
Pedogenesis
Pedogenesis (from the Greek pedo-, or pedon, meaning 'soil, earth,' and genesis, meaning 'origin, birth') (also termed soil development, soil evolution, soil formation, and soil genesis) is the process of soil formation as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizons, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors. Pedogenesis is studied as a branch of pedology, the study of soil in its natural environment. Other branches of pedology are the study of soil morphology, and soil classification. The study of pedogenesis is important to understanding soil distribution patterns in current (soil geography) and past (paleopedology) geologic periods.
  • 5.5K
  • 03 Nov 2022
Biography
John G. Trump
John George Trump (August 21, 1907 – February 21, 1985) was an American electrical engineer, inventor, and physicist. He was a recipient of U.S. President Ronald Reagan's National Medal of Science, and a member of the National Academy of Engineering.[1][2][3] John Trump was noted for developing rotational radiation therapy.[1] Together with Robert J. Van de Graaff, he developed one of the firs
  • 5.5K
  • 02 Dec 2022
Topic Review
P53 Protein famliy
p53 and p73 are critical tumor suppressors that are often inactivated in human cancers through various mechanisms. Owing to their high structural homology, the proteins have many joined functions and recognize the same set of genes involved in apoptosis and cell cycle regulation. p53 is known as the ‘guardian of the genome’ and together with p73 forms a barrier against cancer development and progression. The TP53 is mutated in more than 50% of all human cancers and the germline mutations in TP53 predispose to the early onset of multiple tumors in Li–Fraumeni syndrome (LFS), the inherited cancer predisposition. In cancers where TP53 gene is intact, p53 is degraded. Despite the ongoing efforts, the treatment of cancers remains challenging. Presently, the endeavors focus on reactivating p53 exclusively, neglecting the potential of the restoration of p73 protein for cancer eradication. Taken that several small molecules reactivating p53 failed in clinical trials, there is a need to develop new treatments targeting p53 proteins in cancer. This review outlines the most advanced strategies to reactivate p53 and p73 and describes drug repurposing approaches for the efficient reinstatement of the p53 proteins for cancer therapy.
  • 5.5K
  • 21 Oct 2020
Topic Review
Sustainable Tourism in Fiji
The tourism industry has evolved as a major contributor to economic development and employment creation globally. Over the past seven decades, the tourism industry has experienced growth in both developed and developing countries. Although tourism has significant economic benefits, it often compromises environmental quality. Thus, tourism sustainability becomes an important element in managing the industry. Tourism sustainability has emerged as a leading policy paradigm and is important because tourism is a significant contributor to carbon emissions worldwide.
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  • 02 Jun 2022
Topic Review
Polymers in Wastewater Treatment
The utilization of various types of natural and modified polymers for removing toxicant dyes in wastewater generated by the dye industry is reviewed in this article. Dye wastewater contains large amounts of metals, surfactants, and organic matter, which have adverse effects on human health, potentially causing skin diseases and respiratory problems. The removal of dyes from wastewaters through chemical and physical processes has been addressed by many researchers. Currently, the use of natural and modified polymers for the removal of dyes from wastewater is becoming more common. Although modified polymers are preferred for the removal of dyes, due to their biodegradability and non-toxic nature, large amounts of polymers are required, resulting in higher costs. 
  • 5.5K
  • 20 Oct 2020
Topic Review
Windows 10 Version History (Version 1607)
The Windows 10 Anniversary Update (also known as version 1607 and codenamed "Redstone 1") is the second major update to Windows 10 and the first in a series of updates under the Redstone codenames. It carries the build number 10.0.14393.
  • 5.5K
  • 20 Oct 2022
Biography
Albert Lutuli
Inkosi Albert John Luthuli (very often spelt Lutuli;[1] c. 1898 – 21 July 1967), also known by his Zulu name Mvumbi (English language: continuous rain),[2] was a South Africa n teacher, activist, Nobel Peace Prize winner, and politician. Luthuli was elected president of the African National Congress (ANC) in 1952. At this time, an umbrella organisation that led opposition to the white minori
  • 5.5K
  • 29 Nov 2022
Topic Review
Coordination Polymers
Coordination polymers are solid-state structures consisting of repeating coordination units extending in one, two or three dimensions. Fields applications of the coordination polymers in general and metal-organic frameworks in particular are briefly discussed.
  • 5.5K
  • 31 Jul 2020
Topic Review
Trailer Connectors in North America
A number of standards prevail in North America, or parts of it, for trailer connectors, the electrical connectors between vehicles and the trailers they tow that provide a means of control for the trailers.
  • 5.5K
  • 28 Oct 2022
Topic Review
Magnesium Supplements and Statin Medication
Many investigations have discovered a connection between statins and magnesium supplements. On one hand, increasing research suggests that chronic hypomagnesemia may be an important factor in the etiology of some metabolic illnesses, including obesity and overweight, insulin resistance and type 2 diabetes mellitus, hypertension, alterations in lipid metabolism, and low-grade inflammation. Chronic metabolic problems seem to be prevented by a high Mg intake combined with diet and/or supplements.
  • 5.5K
  • 23 Apr 2023
Topic Review
Coherent States
In physics, specifically in quantum mechanics, a coherent state is the specific quantum state of the quantum harmonic oscillator, often described as a state which has dynamics most closely resembling the oscillatory behavior of a classical harmonic oscillator. It was the first example of quantum dynamics when Erwin Schrödinger derived it in 1926, while searching for solutions of the Schrödinger equation that satisfy the correspondence principle. The quantum harmonic oscillator and hence, the coherent states arise in the quantum theory of a wide range of physical systems. For instance, a coherent state describes the oscillating motion of a particle confined in a quadratic potential well (for an early reference, see e.g. Schiff's textbook). The coherent state describes a state in a system for which the ground-state wavepacket is displaced from the origin of the system. This state can be related to classical solutions by a particle oscillating with an amplitude equivalent to the displacement. These states, expressed as eigenvectors of the lowering operator and forming an overcomplete family, were introduced in the early papers of John R. Klauder, e.g. . In the quantum theory of light (quantum electrodynamics) and other bosonic quantum field theories, coherent states were introduced by the work of Roy J. Glauber in 1963. The concept of coherent states has been considerably abstracted; it has become a major topic in mathematical physics and in applied mathematics, with applications ranging from quantization to signal processing and image processing (see Coherent states in mathematical physics). For this reason, the coherent states associated to the quantum harmonic oscillator are sometimes referred to as canonical coherent states (CCS), standard coherent states, Gaussian states, or oscillator states.
  • 5.5K
  • 20 Oct 2022
Topic Review
Flynn Effect
The Flynn effect is the substantial and long-sustained increase in both fluid and crystallized intelligence test scores that were measured in many parts of the world over the 20th century. When intelligence quotient (IQ) tests are initially standardized using a sample of test-takers, by convention the average of the test results is set to 100 and their standard deviation is set to 15 or 16 IQ points. When IQ tests are revised, they are again standardized using a new sample of test-takers, usually born more recently than the first. Again, the average result is set to 100. However, when the new test subjects take the older tests, in almost every case their average scores are significantly above 100. Test score increases have been continuous and approximately linear from the earliest years of testing to the present. For example, a study published in the year 2009 found that British children's average scores on the Raven's Progressive Matrices test rose by 14 IQ points from 1942 to 2008. Similar gains have been observed in many other countries in which IQ testing has long been widely used, including other Western European countries, Japan, and South Korea. There are numerous proposed explanations of the Flynn effect, as well as some skepticism about its implications. Similar improvements have been reported for semantic and episodic memory. Some research suggests that there may be an ongoing reversed Flynn effect, i.e. a decline in IQ scores, in Norway, Denmark, Australia, Britain, the Netherlands, Sweden, Finland, and German-speaking countries, a development which appears to have started in the 1990s, but in certain cases an apparent reversal is due to cultural changes making parts of intelligence tests obsolete. Meta-analyses indicate that overall, the Flynn effect continues either at the same rate or at a slower rate in developed countries.
  • 5.5K
  • 03 Nov 2022
Topic Review
Pink Tide
The pink tide (Spanish: marea rosa, Portuguese: onda rosa, French: marée rose), or the turn to the left (Spanish: giro a la izquierda, Portuguese: volta à esquerda, French: tournant à gauche), was a political wave and perception of a turn towards left-wing governments in Latin American democracies moving away from the neoliberal economic model at the start of the 21st century. As a term, both phrases are used in contemporary 21st-century political analysis in the news media and elsewhere to refer to a move toward more economic progressive or social progressive policies in Latin America. Such governments have been referred to as "left-of-centre", "left-leaning", and "radical social-democratic". The Latin American countries viewed as part of this ideological trend have been referred to as pink tide nations, with the term post-neoliberalism or socialism of the 21st century being used to describe the movement as well. Some pink tide governments, such as those of Argentina , Brazil , and Venezuela, have been varyingly characterized as being "anti-American", as well as populist, for their rejection of the Washington Consensus, and as authoritarian, particularly in the case of Nicaragua and Venezuela by the 2010s. The pink tide was followed by the conservative wave, a political phenomenon that emerged in the early 2010s as a direct reaction to the pink tide. Some authors have proposed that there are multiple distinct pink tides rather than a single one, with the first pink tide happening during the late 1990s and early 2000s, and a second pink tide encompassing the elections of the late 2010s to early 2020s. A resurgence of the pink tide was kicked off by Mexico in 2018 and Argentina in 2019, and further established by Bolivia in 2020, along with Peru, Honduras, and Chile in 2021, and Colombia in 2022, with the first left-wing president-elect in Colombia's history, according to analysts.
  • 5.5K
  • 14 Nov 2022
Topic Review
Bio-Oil
Bio-oil is a the liquid phase obtained from the pyrolysis of biomass. The composition and amount of bio-oil generated depend not only on the type of the biomass but also on the conditions under which pyrolysis is performed. Most fossil fuels can be replaced by bio-oil-derived products. Thus, bio-oil can be used directly or co-fed along with fossil fuels in boilers, transformed into fuel for car engines by hydrodeoxygenation or even used as a more suitable source for hydrogen production than biomass. On the other hand, due to its rich composition in compounds resulting from the pyrolysis of cellulose, hemicellulose and lignin, bio-oil co-acts as a source of various value-added chemicals such as aromatic compounds.
  • 5.5K
  • 12 May 2021
Topic Review
Qt
Qt (pronounced "cute") is cross-platform software for creating graphical user interfaces as well as cross-platform applications that run on various software and hardware platforms such as Linux, Windows, macOS, Android or embedded systems with little or no change in the underlying codebase while still being a native application with native capabilities and speed. Qt is currently being developed by The Qt Company, a publicly listed company, and the Qt Project under open-source governance, involving individual developers and organizations working to advance Qt. Qt is available under both commercial licenses and open-source GPL 2.0, GPL 3.0, and LGPL 3.0 licenses.
  • 5.5K
  • 28 Nov 2022
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