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Topic Review
Upper Mantle (Earth)
The upper mantle of the Earth begins just beneath the crust about 35 km (22 mi) and ends at the top of the lower mantle at 670 km (420 mi). Temperatures range from approximately 200 °C (392 °F) at the upper boundary with the crust to approximately 900 °C (1,650 °F) at the boundary with the lower mantle. Upper mantle material which has come up onto the surface is made up of about 55% olivine, 35% pyroxene and 5 to 10% of calcium oxide and aluminum oxide minerals such as plagioclase, spinel or garnet, depending upon depth.
  • 15.4K
  • 29 Sep 2022
Topic Review
Vichy France
Vichy France (French: Régime de Vichy) is the common name of the French State (État français) headed by Marshal Philippe Pétain during World War II. Evacuated from Paris to Vichy in the unoccupied "Free Zone" (zone libre) in the southern part of metropolitan France which included French Algeria, it remained responsible for the civil administration of all France as well as the French colonial empire. From 1940 to 1942, while the Vichy regime was the nominal government of all of France except for Alsace-Lorraine, the Germans militarily occupied northern France. While Paris remained the de jure capital of France, the government chose to relocate to the town of Vichy, 360 km (220 mi) to the south in the zone libre, which thus became the de facto capital of the French State. Following the Allied landings in French North Africa in November 1942, southern France was also militarily occupied by Germany and Italy to protect the Mediterranean coastline. Petain's government remained in Vichy as the nominal government of France, albeit one that was obliged by circumstances to collaborate with Germany from November 1942 onwards. The government at Vichy remained there until late 1944, when it lost its authority due to the Allied invasion of France. After being appointed Premier by President Albert Lebrun, Marshal Pétain's cabinet agreed to end the war and signed an Armistice with Germany on 22 June 1940. On 10 July, the French Third Republic was dissolved, and Pétain established an authoritarian regime when the National Assembly granted him full powers. The Vichy government reversed many liberal policies and began tight supervision of the economy, calling for "National Regeneration", with central planning a key feature. Labour unions came under tight government control. Conservative Catholics became prominent and clerical input in schools resumed. Paris lost its avant-garde status in European art and culture. The media were tightly controlled and stressed virulent anti-Semitism, and, after June 1941, anti-Bolshevism. The French State maintained nominal sovereignty over the whole of French territory, but had effective full sovereignty only in the unoccupied southern zone libre ("free zone"). It had limited and only civil authority in the northern zones under military occupation. The occupation was to be a provisional state of affairs, pending the conclusion of the war, which at the time (1940) appeared imminent. The occupation also presented certain advantages, such as keeping the French Navy and French colonial empire under French control, and avoiding full occupation of the country by Germany, thus maintaining a degree of French independence and neutrality. The French government at Vichy never joined the Axis alliance. Germany kept two million French soldiers prisoner, carrying out forced labour. They were hostages to ensure that Vichy would reduce its military forces and pay a heavy tribute in gold, food, and supplies to Germany. French police were ordered to round up Jews and other "undesirables" such as communists and political refugees. Much of the French public initially supported the government, despite its undemocratic nature and its difficult position vis-à-vis the Germans, often seeing it as necessary to maintain a degree of French autonomy and territorial integrity. In November 1942, however, the zone libre was also occupied by Axis forces, leading to the disbandment of the remaining army and the sinking of France's remaining fleet and ending any semblance of independence, with Germany now closely supervising all French officials. Most of the overseas French colonies were originally under Vichy control, but with the Allied invasion of North Africa it lost one colony after another to Charles de Gaulle's Allied-oriented Free France. Public opinion in some quarters turned against the French government and the occupying German forces over time, when it became clear that Germany was losing the war, and resistance to them increased. Following the Allied invasion of France in June 1944 and the liberation of France later that year, the Free French Provisional government of the French Republic (GPRF) was installed by the Allies as France's government, led by de Gaulle. Under a "national unanimity" cabinet uniting the many factions of the French Resistance, the GPRF re-established a provisional French Republic, thus apparently restoring continuity with the Third Republic. Most of the legal French government's leaders at Vichy fled or were subject to show trials by the GPRF, and a number were quickly executed for "treason" in a series of purges (épuration légale). Thousands of collaborators were summarily executed by local communists and the Resistance in so-called "savage purges" (épuration sauvage). The last of the French state exiles were captured in the Sigmaringen enclave by de Gaulle's French 1st Armoured Division in April 1945. Pétain, who had voluntarily made his way back to France via Switzerland, was also put on trial for treason by the new Provisional government, and received a death sentence, but this was commuted to life imprisonment by de Gaulle. Only four senior Vichy officials were tried for crimes against humanity, although many more had participated in the deportation of Jews for extermination in Nazi concentration camps, abuses of prisoners, and severe acts against members of the Resistance.
  • 15.2K
  • 09 Nov 2022
Topic Review
Applications of Fibre Reinforced Polymer
Three FRP shapes are used in Structural Engineering applications: FRP profiles for new construction, FRP rebars and FRP strengthening systems. Applications in bridges, buildings, railway platforms, cooling towers and repair and rehabilitation of existing structures are presented. FRP is a strong and lightweight sustainable material with lower carbon footprint than traditional materials. However, FRPs are not as widely used as expected. FRP use in repair and rehabilitation has seen significant growth, though, over last two decades. The major challenges have been steel-like FRP elements, lack of ductility, almost no legal design guidelines and inadequate knowledge about fire and durability performance. The future of FRPs can be promising if engineers use this material more for net-zero carbon construction, and to effectively deal with climate emergency.
  • 15.2K
  • 28 Mar 2022
Topic Review
Longitudinal Static Stability
In flight dynamics, longitudinal static stability is the stability of an aircraft in the longitudinal, or pitching, plane under steady flight conditions. This characteristic is important in determining whether a human pilot will be able to control the aircraft in the pitching plane without requiring excessive attention or excessive strength.
  • 15.2K
  • 20 Oct 2022
Topic Review
List of Highest Mountains on Earth
There are at least 108 mountains on Earth with elevations of 7,200 metres (23,622 ft) or greater above sea level. The vast majority of these mountains are located on the edge of the Indian and Eurasian plate- namely, in China , Pakistan , Nepal and India .
  • 15.2K
  • 10 Nov 2022
Topic Review
Single Point Mooring (SPM) Systems with Buoys
The SPM system consists of four main components, namely, the body of the buoy, the anchoring and mooring components, the fluid transfer system and the ancillary elements. Static legs linked to the seabed underneath the surface keep the buoy body in place. Above the water level, the body has a spinning portion that is attached to the offloading/loading tanker. A roller bearing, referred to as the main bearing, connects these two portions. Due to this array, the anchored tanker can easily weather-vane around the buoy and find a steady position. The concept of the buoy is determined by the type of bearing utilized and the divide between the rotating and geostatic sections. The buoy’s size is determined by the amount of counter buoyancy required to keep the anchor chains in place, and the chains are determined by environmental conditions and vessel size.
  • 15.1K
  • 19 Nov 2021
Topic Review
Social Evolution
Social evolution refers to the gradual and continuous change in social structures, behaviors, and institutions over time. It encompasses the development and transformation of societies, including advancements in technology, shifts in cultural norms, and alterations in political and economic systems, often driven by factors such as innovation, conflict, and interaction with the environment. This concept underpins various theories in sociology and anthropology, offering insights into how societies adapt and evolve in response to internal and external pressures.
  • 15.1K
  • 26 Jan 2024
Topic Review
Mercedes-Benz 9G-Tronic Transmission
9G-Tronic is Mercedes-Benz's trademark name for its nine-speed automatic transmission, starting off with the W9A 700 (Wandler-9-Gang-Automatik bis 700 Nm Eingangsdrehmoment; converter-9-gear-automatic with 516 lb-ft maximum input torque; type 725.0) as core model.
  • 15.1K
  • 30 Nov 2022
Topic Review
Apple juice fermentation process
This work emphasized the apple fermentation process and showed how the fermentation can be affected by the first material composition and the used microorganisms.
  • 15.1K
  • 19 Aug 2020
Topic Review
Apostolic Age
The Apostolic Age of the history of Christianity is traditionally regarded as the period of the Twelve Apostles, dating from the Great Commission of the Apostles by the risen Jesus in Jerusalem around 33 AD until the death of the last Apostle, believed to be John the Apostle in Anatolia c. 100. Traditionally, the Apostles are believed to have dispersed from Jerusalem, founding the Apostolic Sees. It holds special significance in Christian tradition as the age of the direct apostles of Jesus Christ. One major primary source for the "Apostolic Age" is the Acts of the Apostles, but its historical accuracy is questioned by some and its coverage is partial, focusing especially from Acts 15:36 onwards on the ministry of Paul (an apostle to the Gentiles, but not one of the original twelve apostles – Rom. 1:1; 11:13) and his companions, and ending around 62 AD with Paul preaching in Rome under house arrest. According to most scholars, the followers of Jesus were composed principally from apocalyptic Jewish sects during the late Second Temple period of the 1st century. Some Early Christian groups were strictly Jewish, such as the Ebionites and the early-church leaders in Jerusalem, collectively called Jewish Christians. During this period, they were led by James the Just. According to Acts 9:1–2, they described themselves as 'disciples of the Lord' and [followers] 'of the Way', and according to Acts 11:26 a settled community of disciples at Antioch were the first to be called 'Christians'. Saul of Tarsus, commonly known as Paul the Apostle, persecuted the early Jewish Christians, such as Saint Stephen, then converted and adopted the title of "Apostle to the Gentiles" and started proselytizing among the Gentiles. He persuaded the leaders of the Jerusalem Church to allow Gentile converts exemption from most Jewish commandments at the Council of Jerusalem. According to the Oxford Dictionary of the Christian Church, Paul's influence on Christian thinking is more significant than any other New Testament author, however the relationship of Paul the Apostle and Judaism is still disputed today (see the link for details). After the Destruction of the Second Temple in AD 70 during the First Jewish-Roman War, or at the latest following the Bar Kokhba revolt of 132, Jerusalem ceased to be the center of the Christian church, and its bishops became "suffragans" (subordinates) of the Metropolitan bishop of Caesarea. In the 2nd century, Christianity established itself as a predominantly Gentile religion that spanned the Roman Empire and beyond.
  • 15.1K
  • 27 Oct 2022
Topic Review
History of Islam
The history of Islam concerns the political, social, economic and cultural developments of the Islamic civilization. Despite concerns about the reliability of early sources, most historians believe that Islam originated in Mecca and Medina at the start of the 7th century, approximately 600 years after the founding of Christianity. Muslims, however, believe that it did not start with Muhammad, but that it was the original faith of others whom they regard as prophets, such as Jesus, David, Moses, Abraham, Noah and Adam. In 610 CE, Muhammad began receiving what Muslims consider to be divine revelations. Muhammad's message won over a handful of followers and was met with increasing opposition from Meccan notables. In 618, after he lost protection with the death of his influential uncle Abu Talib, Muhammad migrated to the city of Yathrib (now known as Medina). With Muhammad's death in 632, disagreement broke out over who would succeed him as leader of the Muslim community which was eventually resurrected leading to the First Fitna. The dispute would intensify greatly after the Battle of Karbala, in which Muhammad's grandson Hussein ibn Ali was killed by the ruling Umayyad Caliph Yazid I, and the outcry for revenge divided the early Islamic community. By the 8th century, the Islamic empire extended from Iberia in the west to the Indus river in the east. Polities such as those ruled by the Umayyads (in the Middle East and later in Iberia), Abbasids, Fatimids, and Mamluks were among the most influential powers in the world. The Islamic Golden Age gave rise to many centers of culture and science and produced notable astronomers, mathematicians, doctors and philosophers during the Golden Age of Islam. In the early 13th century, the Delhi Sultanate took over northern parts of Indian subcontinent. In the 13th and 14th centuries, destructive Mongol invasions from the East, along with the loss of population in the Black Death, greatly weakened the traditional centers of the Islamic world, stretching from Persia to Egypt, but in the Early Modern period, the Ottomans, the Safavids, and the Mughals were able to create new world powers again. During the 19th and early 20th centuries, most parts of the Muslim world fell under the influence or direct control of European "Great Powers." Their efforts to win independence and build modern nation states over the course of the last two centuries continue to reverberate to the present day.
  • 15.1K
  • 11 Nov 2022
Topic Review
Blonde Stereotype
Blonde stereotypes are stereotypes of blond-haired women. Sub-types include the "blonde bombshell" and the "dumb blonde". Blondes are differently stereotyped from brunettes as more desirable and less intelligent. There are many blonde jokes made on these premises. Although chiefly aimed at women, jokes of this style have also been aimed at similar stereotypes associated with men, such as the "dumb jock" and the "surfer dude".
  • 15.1K
  • 25 Oct 2022
Topic Review
Georgism
Georgism, also called in modern times geoism and known historically as the single tax movement, is an economic ideology holding that, although people should own the value they produce themselves, the economic rent derived from land – including from all natural resources, the commons, and urban locations – should belong equally to all members of society. Developed from the writings of American economist and social reformer Henry George, the Georgist paradigm seeks solutions to social and ecological problems, based on principles of land rights and public finance which attempt to integrate economic efficiency with social justice. Georgism is concerned with the distribution of economic rent caused by land ownership, natural monopolies, pollution and the control of commons, including title of ownership for natural resources and other contrived privileges (e.g. intellectual property). Any natural resource which is inherently limited in supply can generate economic rent, but the classical and most significant example of land monopoly involves the extraction of common ground rent from valuable urban locations. Georgists argue that taxing economic rent is efficient, fair and equitable. The main Georgist policy recommendation is a tax assessed on land value, arguing that revenues from a land value tax (LVT) can be used to reduce or eliminate existing taxes (such as on income, trade, or purchases) that are unfair and inefficient. Some Georgists also advocate for the return of surplus public revenue to the people by means of a basic income or citizen's dividend. The concept of gaining public revenues mainly from land and natural resource privileges was widely popularized by Henry George through his first book, Progress and Poverty (1879). The philosophical basis of Georgism dates back to several early thinkers such as John Locke, Baruch Spinoza and Thomas Paine. Economists since Adam Smith and David Ricardo have observed that a public levy on land value does not cause economic inefficiency, unlike other taxes. A land value tax also has progressive tax effects. Advocates of land value taxes argue that they would reduce economic inequality, increase economic efficiency, remove incentives to underutilize urban land and reduce property speculation. Georgist ideas were popular and influential during the late 19th and early 20th century. Political parties, institutions and communities were founded based on Georgist principles during that time. Early devotees of Henry George's economic philosophy were often termed Single Taxers for their political goal of raising public revenue mainly or only from a land value tax, although Georgists endorsed multiple forms of rent capture (e.g. seigniorage) as legitimate. The term Georgism was invented later, and some prefer the term geoism as more generic.
  • 15.1K
  • 08 Nov 2022
Topic Review
Subject–Verb–Object
In linguistic typology, subject–verb–object (SVO) is a sentence structure where the subject comes first, the verb second, and the object third. Languages may be classified according to the dominant sequence of these elements in unmarked sentences (i.e., sentences in which an unusual word order is not used for emphasis). English is included in this group. An example is "Sam ate oranges." The label often includes ergative languages that do not have subjects, but have an agent–verb–object (AVO) order. SVO is the second-most common order by number of known languages, after SOV. Together, SVO and SOV account for more than 75% of the world's languages. It is also the most common order developed in Creole languages, suggesting that it may be somehow more initially "obvious" to human psychology. Languages regarded as SVO include: All Bantu languages, Albanian, Arabic dialects, Assyrian, Bosnian, Bulgarian,[a 1] Chinese, English, Estonian, Finnish (but see below), French, Greek, Hausa, Icelandic (with the V2 restriction), Igbo, Italian, Javanese, Khmer, Latvian, Macedonian, Malay (Indonesian, Malaysian), Modern Hebrew, Norwegian (with the V2 restriction), Polish, Portuguese, Quiché, Reo Rapa, Romanian, Russian (but see below), Slovene, Spanish, Swedish (with the V2 restriction), Thai and Lao, Ukrainian (but see below), Vietnamese and Yoruba. Ancient Greek has free syntactic order, though Classical Greeks tended to favor SOV. Many famous phrases are SVO, however.
  • 15.1K
  • 29 Nov 2022
Topic Review
Fine Motor Skill Development in Young Children
Fine motor skills (FMS) are fundamental for children’s growth, influencing their writing progress and everyday activities. Children's FMS are also assessed in their school readiness assessment, DIFER (Diagnostic System for Assessing Development) which is a widely used and standardized school readiness test in Hungary and some European countries. However, the development of these skills is a multifaceted process that is affected by various factors. Consequently, it becomes essential to comprehend the disparities in children’s fine motor skills (FMS) development and the predictive factors. 
  • 15.0K
  • 07 Oct 2023
Topic Review
Proton–Proton Chain Reaction
The proton–proton chain reaction is one of two known sets of nuclear fusion reactions by which stars convert hydrogen to helium. It dominates in stars with masses less than or equal to that of the Sun, whereas the CNO cycle, the other known reaction, is suggested by theoretical models to dominate in stars with masses greater than about 1.3 times that of the Sun. In general, proton–proton fusion can occur only if the kinetic energy (i.e. temperature) of the protons is high enough to overcome their mutual electrostatic repulsion. In the Sun, deuterium-producing events are rare. Diprotons are the much more common result of proton–proton reactions within the star, and diprotons almost immediately decay back into two protons. Since the conversion of hydrogen to helium is slow, the complete conversion of the hydrogen in the core of the Sun is calculated to take more than ten billion years. Although called the "proton–proton chain reaction", it is not a chain reaction in the normal sense. In most nuclear reactions, a chain reaction designates a reaction that produces a product, such as neutrons given off during fission, that quickly induces another such reaction. The proton-proton chain is, like a decay chain, a series of reactions. The product of one reaction is the starting material of the next reaction. There are two such chains leading from Hydrogen to Helium in the Sun. One chain has five reactions, the other chain has six.
  • 15.0K
  • 21 Oct 2022
Topic Review
2020–2021 Taal Volcano Eruptions
Taal Volcano in Batangas, Philippines began to erupt on January 12, 2020, when a phreatomagmatic eruption from its main crater spewed ashes over Calabarzon, Metro Manila, and some parts of Central Luzon and Ilocos Region, resulting in the suspension of school classes, work schedules, and flights in the area. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) subsequently issued an Alert Level 4, indicating "that a hazardous explosive eruption is possible within hours to days." Volcanic activity continued into 2021, when smaller eruptions occurred in July 2021.
  • 15.0K
  • 24 Nov 2022
Topic Review
Value (Ethics)
In ethics, value denotes the degree of importance of some thing or action, with the aim of determining what actions are best to do or what way is best to live (normative ethics), or to describe the significance of different actions. Value systems are prospective and prescriptive beliefs; they affect ethical behavior of a person or are the basis of their intentional activities. Often primary values are strong and secondary values are suitable for changes. What makes an action valuable may in turn depend on the ethical values of the objects it increases, decreases or alters. An object with "ethic value" may be termed an "ethic or philosophic good" (noun sense). Values can be defined as broad preferences concerning appropriate courses of actions or outcomes. As such, values reflect a person's sense of right and wrong or what "ought" to be. "Equal rights for all", "Excellence deserves admiration", and "People should be treated with respect and dignity" are representatives of values. Values tend to influence attitudes and behavior and these types include ethical/moral values, doctrinal/ideological (religious, political) values, social values, and aesthetic values. It is debated whether some values that are not clearly physiologically determined, such as altruism, are intrinsic, and whether some, such as acquisitiveness, should be classified as vices or virtues.
  • 15.0K
  • 06 Oct 2022
Topic Review
Outline of Heresies in the Catholic Church
The following outline is provided as an overview of and topical guide to heresies (as regarded by the Roman Catholic Church): Heresy, in Catholicism, is defined as belief that conflicts with established Catholic dogma.
  • 14.9K
  • 16 Nov 2022
Topic Review
Hindu Views on Evolution
Hinduism includes a range of viewpoints about the origin of life, creationism and evolution. There is no single story of creation, due to dynamic diversity of Hinduism, and these are derived from various sources like Vedas, some from the Brahmanas, some from Puranas; some are philosophical, based on concepts, and others are narratives. The Rigveda mentions the Hiranyagarbha ("golden embryo") as the source of the creation of the Universe, similar to the world egg motif found in the creation myths of many other civilizations. It also contains a myth of proto-Indo-European origin, in which the creation arises out of the dismemberment of a cosmic being (the Purusha) who is sacrificed by the gods. As for the creation of the primordial gods themselves, the Nasadiya Sukta of Rigveda takes a near-agnostic stand, stating that the Gods came into being after the world's creation, and nobody knows when the world first came into being. In the later Puranic texts, the creator god Brahma is described as performing the act of 'creation', or more specifically of 'propagating life within the universe'. Some texts consider him equivalent to the Hiranyagarbha or the Purusha, while others state that he arose out of these. Brahma is a part of the trinity of gods that also includes Vishnu and Shiva, who are responsible for 'preservation' and 'destruction' (of the universe) respectively. Many Hindu texts mention the cycle of creation and destruction. The Shatapatha Brahmana states that the current human generation descends from Manu, the only man who survived a great deluge after being warned by the God. This legend is comparable to the other flood legends, such as the story of the Noah's Ark mentioned in the Bible and the Quran. Hindus find support for, or foreshadowing of evolutionary ideas in scriptures. For example, the concept of Dashavatara can be seen as having some similarities to Charles Darwin's theory of evolution.The first incarnation of Vishnu in the form of a fish resembles the evolutionary origin of fish in the Silurian Period. In a survey of 909 people, 77% of its respondents in India agreed that enough scientific evidence exists to support Charles Darwin’s Theory of Evolution, and 85% of God-believing people said they agree with evolution as well. According to the survey conducted by Pew Forum in the United States , 80% of Hindus agree that evolution is the best explanation for the origin of human life on earth. However, in India, there were minimal references to Darwinism in the 1800s. Elements of Victorian England opposed the idea of Darwinism. Hindus already had present notion of common ancestry between humans and animals. The Hindu dharma believes that the gods have animal features, showing a theory that humans can be reborn again as animals or with their features.
  • 14.9K
  • 21 Oct 2022
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