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Topic Review
Lotus-Leaf-Inspired Biomimetic Coatings
A universal infrastructural issue is wetting of surfaces; millions of dollars are invested annually for rehabilitation and maintenance of infrastructures including roadways and buildings to fix the damages caused by moisture and frost. The biomimicry of the lotus leaf can provide superhydrophobic surfaces that can repel water droplets, thus reducing the penetration of moisture, which is linked with many deterioration mechanisms in infrastructures, such as steel corrosion, sulfate attack, alkali-aggregate reactions, and freezing and thawing. In cold-region countries, the extent of frost damage due to freezing of moisture in many components of infrastructures will be decreased significantly if water penetration can be minimized. Consequently, it will greatly reduce the maintenance and rehabilitation costs of infrastructures.
  • 9.1K
  • 11 Jun 2022
Topic Review
Effects of Frankincense Compounds
Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection.
  • 9.1K
  • 11 Jul 2022
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.
  • 9.1K
  • 27 Nov 2022
Topic Review
Lobe-Finned Fish
Sarcopterygii (/ˌsɑːrkɒptəˈrɪdʒi.aɪ/; from grc σάρξ (sárx) 'flesh', and πτέρυξ (ptérux) 'wing, fins')—sometimes considered synonymous with Crossopterygii (from grc κροσσός (krossós) 'fringe')—is a taxon (traditionally a class or subclass) of the bony fishes whose members are known as lobe-finned fishes. The group Tetrapoda, a superclass including amphibians, reptiles (including dinosaurs and therefore birds), and mammals, evolved from certain sarcopterygians; under a cladistic view, tetrapods are themselves considered a group within Sarcopterygii. The known extant non-tetrapod sarcopterygians include two species of coelacanths and six species of lungfishes.
  • 9.1K
  • 21 Nov 2022
Topic Review
Feminist Political Economy
Feminist political economy is a concept from feminist material scholarship.  It connects market relations with domestic relations. It examines the roles of women, tensions related to women’s paid and unpaid work, how production and reproduction issues affect women, and the interactions at the micro, meso, and macro level contexts within women's lives.  
  • 9.1K
  • 28 Oct 2020
Topic Review
Lipid Membrane
The biological lipid membrane is the key element for the maintenance of cell architecture and physiology. Lipid membranes act as a barrier separating the inner cellular space from the outer environment and further helping in the transmission of signals across the cell boundary. The correct composition and structure of cell membranes define key pathophysiological aspects of cells.
  • 9.1K
  • 23 Dec 2020
Topic Review
Meat Extenders
Meat extenders are non-meat substances with high protein contents used to partially substitue (or extend) the meat content in meat products. Initially devised to reduce costs (as meat is the most expensive ingredient in meat products) they can become now a useful strategy to develop more sustainable and healthier meat products.
  • 9.1K
  • 28 Aug 2020
Topic Review
Preterism
Preterism, a Christian eschatological view, interprets some (partial preterism) or all (full preterism) prophecies of the Bible as events which have already happened. This school of thought interprets the Book of Daniel as referring to events that happened from the 7th century BC until the first century AD, while seeing the prophecies of the Book of Revelation as events that happened in the first century AD. Preterism holds that Ancient Israel finds its continuation or fulfillment in the Christian church at the destruction of Jerusalem in AD 70. The term preterism comes from the Latin praeter, which is a prefix denoting that something is "past" or "beyond". Adherents of preterism are known as preterists. Preterism teaches that either all (full preterism) or a majority (partial preterism) of the Olivet discourse had come to pass by AD 70. Historically, preterists and non-preterists have generally agreed that the Jesuit Luis de Alcasar (1554–1613) wrote the first systematic preterist exposition of prophecy Vestigatio arcani sensus in Apocalypsi (published in 1614) during the Counter-Reformation.
  • 9.1K
  • 11 Oct 2022
Topic Review
Social Group
In sociology, a group is a social entity composed of two or more individuals who interact with one another, share a sense of identity, and are bound by a common purpose or goal. These social groups can range from intimate and small-scale, such as families, to larger and more complex structures like organizations or communities. The study of groups in sociology provides insights into human social behavior, dynamics, and the influence of collective processes on individuals within the societal framework.
  • 9.1K
  • 25 Jan 2024
Topic Review
Non-Hispanic or Latino Whites
Non-Hispanic whites or Non-Latino whites are European Americans, Middle Eastern Americans, and North African Americans as defined by the United States Census Bureau. Americans of European ancestry represent ethnic groups and more than half of the white population are German, Irish, English, Italian and Polish Americans. In the United States , this population was first derived from English (and, to a lesser degree, French) settlement of the Americas, as well as settlement by other Europeans such as the Germans and Dutch that began in the 17th century (see History of the United States). Continued growth since the early 19th century is attributed to sustained very high birth rates alongside relatively low death rates among settlers and natives alike as well as periodically massive immigration from European countries, especially Germany, Ireland, England, Italy, Greece, the Netherlands, France and Wales, as well as Poland, Russia, and many more countries. It typically refers to an English-speaking American in distinction to Spanish speakers in Mexico and the Southwestern states. In some parts of the country, the term Anglo-American is used to refer to non-Hispanic white English speakers as distinct from Spanish speakers although the term is more frequently used to refer to people of British or English descent and might include white people of Hispanic descent who no longer speak Spanish.
  • 9.1K
  • 27 Oct 2022
Topic Review
Sophia (Gnosticism)
Sophia (Koinē Greek: Σοφíα "Wisdom", Coptic: ⲧⲥⲟⲫⲓⲁ "the Sophia") is a major theme, along with Knowledge (γνῶσις gnosis, Coptic sooun), among many of the early Christian knowledge-theologies grouped by the heresiologist Irenaeus as gnostikoi (γνωστικοί), ‘knowing’ or ‘men that claimed to have deeper wisdom’. Gnosticism is a 17th-century term expanding the definition of Irenaeus' groups to include other syncretic and mystery religions. In Gnosticism, Sophia is a feminine figure, analogous to the human soul but also simultaneously one of the feminine aspects of God. Gnostics held that she was the syzygy (female twin divine Aeon) of Jesus (i.e. the Bride of Christ), and Holy Spirit of the Trinity. She is occasionally referred to by the Hebrew equivalent of Achamōth (Ἀχαμώθ, Hebrew: חכמה‎ chokhmah) and as Prunikos (Προύνικος). In the Nag Hammadi texts, Sophia is the lowest Aeon, or anthropic expression of the emanation of the light of God. She is considered to have fallen from grace in some way, in so doing creating or helping to create the material world.
  • 9.1K
  • 23 Nov 2022
Topic Review
Caret
The caret (/ˈkærɪt/) is a V-shaped grapheme, usually inverted and sometimes extended, used in proofreading and typography to indicate that additional material needs to be inserted at this point in the text. There is a similar mark, ^, that has a variety of uses in programming, mathematics and other contexts. The symbol was included in typewriters and computer printers so that circumflex accents could be overprinted on letters (as in ô or ŵ). The character became reused in computer languages for many other purposes, and over time its appearance was enlarged and lowered, making it unusable as an accent mark. This symbol is often called a "caret", but this page will call it a "circumflex" to distinguish it from a true caret. This circumflex is not to be confused with other chevron-shaped characters, such as the circumflex accent, the turned v or the logical AND, which may occasionally be called carets.
  • 9.1K
  • 09 Oct 2022
Topic Review
Load Frequency Control System
Power systems are complex systems that have great importance to socio-economic development due to the fact that the entire world relies on the electric network power supply for day-to-day life. Therefore, for the stable operation of power systems, several protection and control techniques are necessary. Among various power system controls, the load frequency control (LFC) is the most time-consuming control mechanism of power systems due to the involvement of mechanical parts. As the control algorithms of frequency stabilization deliver control signals in the timescale of seconds, LFC systems cannot handle complicated data validation algorithms, making them more vulnerable to disturbances and cyber-attacks. Hence advanced research is highly encouraged in the field of development of attack resilient frequency stabilization techniques and in the area of cyber-security of LFC systems.
  • 9.1K
  • 26 Oct 2020
Topic Review
Mercedes-Benz CLA-Class
The Mercedes-Benz CLA class is a series of luxury compact executive cars manufactured by Mercedes-Benz since 2013. The first generation was a four-door sedan based on the platform of the W176 A-Class and W246 B-Class compact cars, marketed as a four-door coupé. In 2015, Mercedes-Benz expanded the CLA family to include the Shooting Brake, a station wagon configuration. As the V177 A-Class sedan took its place as the budget-conscious sedan, the second generation got longer and wider than the W205 C-Class. The CLA is Mercedes-Benz's first front-wheel drive vehicle offered in the North American market. The CLA range is positioned above the A-Class and it is nearly on the level of the C-Class in the Mercedes model range, and models tend to be less practical than the A-Class it is based on. The CLA first went on sale in Europe in April 2013, and was subsequently introduced in the United States in September 2013. Its largest markets are Western Europe and the United States. Global cumulative CLA sales reached 100,000 during its first year, cited as "our best launch in 20 years" by Mercedes-Benz. Worldwide, Mercedes-Benz sold about 750,000 units of the first generation.
  • 9.0K
  • 28 Oct 2022
Topic Review
Fruit Carving
Fruit carving is the art of carving fruit, a very common technique in Europe and Asian countries, and particularly popular in Thailand, China and Japan. There are many fruits that can be used in this process; the most popular one that artists use are watermelons, apples, strawberries, pineapples, and cantaloupes.
  • 9.0K
  • 11 Nov 2022
Topic Review
Financial Crisis of 2007–08
The financial crisis of 2007–08, also known as the global financial crisis and the 2008 financial crisis, was a severe worldwide economic crisis considered by many economists to have been the most serious financial crisis since the Great Depression of the 1930s, to which it is often compared. It began in 2007 with a crisis in the subprime mortgage market in the United States , and developed into a full-blown international banking crisis with the collapse of the investment bank Lehman Brothers on September 15, 2008. Excessive risk-taking by banks such as Lehman Brothers helped to magnify the financial impact globally. Massive bail-outs of financial institutions and other palliative monetary and fiscal policies were employed to prevent a possible collapse of the world financial system. The crisis was nonetheless followed by a global economic downturn, the Great Recession. The Asian markets (China, Hong Kong, Japan, India, etc.) were immediately impacted and volatilized after the U.S. sub-prime crisis. The European debt crisis, a crisis in the banking system of the European countries using the euro, followed later. In 2010, the Dodd–Frank Wall Street Reform and Consumer Protection Act was enacted in the US following the crisis to "promote the financial stability of the United States". The Basel III capital and liquidity standards were adopted by countries around the world.
  • 9.0K
  • 11 Nov 2022
Topic Review
Androcentrism
Androcentrism is a cultural and societal phenomenon characterized by the prioritization of male perspectives, experiences, and values over those of women. It manifests in various aspects of society, including language, media representation, and institutional practices, perpetuating gender inequalities and reinforcing patriarchal power structures.
  • 9.0K
  • 08 Feb 2024
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'.
  • 9.0K
  • 15 Nov 2022
Topic Review
Refractive Index and Extinction Coefficient of Thin-Film Materials
The derivation of the Forouhi–Bloomer dispersion equations is based on obtaining an expression for k as a function of photon energy, symbolically written as k(E), starting from first principles quantum mechanics and solid state physics. An expression for n as a function of photon energy, symbolically written as n(E), is then determined from the expression for k(E) in accordance to the Kramers–Kronig relations which states that n(E) is the Hilbert Transform of k(E). The Forouhi–Bloomer dispersion equations for n(E) and k(E) of amorphous materials are given as: [math]\displaystyle{ k(E) = \frac{A(E-E_g)^2}{E^2-BE+C} \ }[/math] [math]\displaystyle{ n(E) = n(\infty)+\frac{(B_0 E + C_0 )}{E^2-BE+C} \ }[/math] The five parameters A, B, C, Eg, and n(∞) each have physical significance. Eg is the optical energy band gap of the material. A, B, and C depend on the band structure of the material. They are positive constants such that 4C-B2 > 0. Finally, n(∞), a constant greater than unity, represents the value of n at E = ∞. The parameters B0 and C0 in the equation for n(E) are not independent parameters, but depend on A, B, C, and Eg. They are given by: [math]\displaystyle{ B_0 = \frac{A}{Q} \ \left (\frac{-B^2}{2} \ + E_gB - {E_g}^2 + C \right) }[/math] [math]\displaystyle{ C_0 = \frac{A}{Q} \ \left [({E_g}^2 + C) \frac{B}{2} \ - 2E_g C \right] }[/math] where [math]\displaystyle{ Q = \frac{1}{2} \ (4C - B^2 )^{\frac{1}{2}} }[/math] Thus, for amorphous materials, a total of five parameters are sufficient to fully describe the dependence of both n and k on photon energy, E. For crystalline materials which have multiple peaks in their n and k spectra, the Forouhi–Bloomer dispersion equations can be extended as follows: [math]\displaystyle{ k(E) = \sum_{i=1}^q \left [\frac{A_i(E - E_{g_i})^2}{E^2-B_iE+C_i} \right] }[/math] [math]\displaystyle{ n(E) = n(\infty)+\sum_{i=1}^q \left [\frac{B_{0_i}E+C_{0_i}}{E^2-B_iE+C_i} \right] }[/math] The number of terms in each sum, q, is equal to the number of peaks in the n and k spectra of the material. Every term in the sum has its own values of the parameters A, B, C, Eg, as well as its own values of B0 and C0. Analogous to the amorphous case, the terms all have physical significance.
  • 9.0K
  • 31 Oct 2022
Topic Review
Toophan
The Toophan (Persian: طوفان‎ "Storm", rarely Toofan) is an Iranian SACLOS anti-tank guided missile reverse-engineered from the United States of America BGM-71 TOW missile. The Toophan 1, an unlicensed copy of the BGM-71A TOW missile, began mass production in 1988 and the Toophan 2, a BGM-71C ITOW variant, was publicly shown in 2000. The Toophan comes in at least 11 variants, many of which are poorly documented, including variants with laser guidance, thermobaric warheads, and tandem-warheads with increased penetration. The Toophan is manufactured jointly by the Aerospace Industries Organization of Iran and Iran Electronics Industries. It's normally deployed from ground-based tripods, and can also be mounted on fighting vehicles and helicopters. Like the BGM-71 TOW missile, the Toophan is a large, rugged, powerful, and reliable anti-tank guided missile deployed by small teams against tanks, armored vehicles, buildings, and other targets. The Toophan forms the backbone of the Iranian Armed Forces's ATGM inventory and is procured in large quantities in a variety of variants. The Toophan has been exported to the governments of Iraq and Syria and to a large number of non-state actors in the Middle East, and has been used in the Iran–Iraq War, the 2006 Lebanon War and the Iraqi, Syrian, and Yemeni Civil Wars.
  • 9.0K
  • 14 Nov 2022
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