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Topic Review

Solid Waste Management in Middle East Arab Countries

Solid waste production, specifically construction waste, in Middle Eastern Arab countries has dramatically increased. This is characterized by several factors, including rapid urbanization, common food wasting habits, diverse culture, lack of proper planning of solid waste processes, insufficient equipment, as well as lack of proper funding. The exponential growth in solid waste generation rates has led to hazards to health and the environment, causing issues related to air and water pollution under the already increasing pressure of climate change.

7.7K
17 Nov 2022

Topic Review

Sexual Fetishism

Sexual fetishism or erotic fetishism is a sexual fixation on a nonliving object or nongenital body part. The object of interest is called the fetish; the person who has a fetish for that object is a fetishist. A sexual fetish may be regarded as a non-pathological aid to sexual excitement, or as a mental disorder if it causes significant psychosocial distress for the person or has detrimental effects on important areas of their life. Sexual arousal from a particular body part can be further classified as partialism. While medical definitions restrict the term sexual fetishism to objects or body parts, fetish can, in common discourse, also refer to sexual interest in specific activities.

7.7K
14 Oct 2022

Topic Review

House of Bonaparte

The House of Bonaparte (originally Buonaparte) was an imperial and royal European dynasty founded in 1804 by Italian noble Carlo Buonaparte and his son Napoleon I, a French military leader of Italian heritage who had risen to notability out of the French Revolution and who in 1804 transformed the First French Republic into the First French Empire, five years after his coup d'état of November 1799. Napoleon turned the Grande Armée against every major European power and dominated continental Europe through a series of military victories during the Napoleonic Wars. He installed members of his family on the thrones of client states, extending the power of the dynasty. The House of Bonaparte formed the Imperial House of France during the French Empire, together with some non-Bonaparte family members. In addition to holding the title of Emperor of the French, the Bonaparte dynasty held various other titles and territories during the Napoleonic Wars, including their ancestral Kingdom of Italy, the Kingdom of Spain, the Kingdom of Westphalia, the Kingdom of Holland, and the Kingdom of Naples. The dynasty held power for around a decade until the Napoleonic Wars began to take their toll. Making very powerful enemies, such as Austria, Britain, Russia, and Prussia, as well as royalist (particularly Bourbon) restorational movements in France, Spain, the Two Sicilies, and Sardinia, the dynasty eventually collapsed due to the final defeat of Napoleon at the Battle of Waterloo and the restoration of former dynasties by the Congress of Vienna. During the reign of Napoleon I, the Imperial Family consisted of the Emperor's immediate relations – his wife, son, siblings, and some other close relatives, namely Joachim Murat, Joseph Fesch, and Eugène de Beauharnais. Between 1852 and 1870, there was a Second French Empire, when a member of the Bonaparte dynasty again ruled France: Napoleon III, the youngest son of Louis Bonaparte. However, during the Franco-Prussian War of 1870–1871, the dynasty was again ousted from the Imperial Throne. Since that time, there has been a series of pretenders. Supporters of the Bonaparte family's claim to the throne of France are known as Bonapartists. Current head Jean-Christophe, Prince Napoléon, has a Bourbon mother.

7.7K
11 Nov 2022

Topic Review

Permian–Triassic Extinction Event

The Permian–Triassic extinction event, also known as the P–Tr extinction, the P–T extinction, the End-Permian Extinction, and colloquially as the Great Dying, formed the boundary between the Permian and Triassic geologic periods, as well as between the Paleozoic and Mesozoic eras, approximately 252 million years ago. It is the Earth's most severe known extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct. It was the largest known mass extinction of insects. Some 57% of all biological families and 83% of all genera became extinct. There is evidence for one to three distinct pulses, or phases, of extinction. Potential causes for those pulses include one or more large meteor impact events, massive volcanic eruptions (such as the Siberian Traps), and climate change brought on by large releases of underwater methane or methane-producing microbes. The speed of the recovery from the extinction is disputed. Some scientists estimate that it took 10 million years (until the Middle Triassic), due both to the severity of the extinction and because grim conditions returned periodically for another 5 million years. However, studies in Bear Lake County, near Paris, Idaho, showed a relatively quick rebound in a localized Early Triassic marine ecosystem, taking around 2 million years to recover, suggesting that the impact of the extinction may have been felt less severely in some areas than others.

7.7K
11 Oct 2022

Topic Review

Grade Retention

Grade retention is a strategy for the remediation of learning or developmental delays. Students who cannot keep up with their peers or do not meet a predefined level repeat the same grade once again and by doing so have an extra year to get at the level that is needed to successfully manage the next grade. There are considerable doubts as regards the usefulness and effectiveness of retaining grades. Studies conclude that in the short term retaining grades may have a positive effect on academic achievement, but that this gain disappears in the longer term.

7.7K
30 Oct 2020

Topic Review

Hoveyda–Grubbs Catalyst

Hoveyda–Grubbs-type complexes, ruthenium catalysts for olefin metathesis, have gained increased interest as a research target in the interdisciplinary research fields of chemistry and biology because of their high functional group selectivity in olefin metathesis reactions and stabilities in aqueous media.

7.7K
26 Mar 2021

Topic Review

Critical Factors in Renewable Energy Generation

The factors influencing the development of renewable energy in the electrical power sector can be grouped into four main clusters: (i) economic factors, (ii) legal and policy factors, (iii) social acceptance factors, and (iv) adverse impacts of renewable energy projects on the ecological environment.

7.7K
16 Dec 2021

Topic Review

Vegetable Oils as Lubricants

Vegetable oils have been used as metalworking fluids (MWFs) for many years, particularly in small-scale metalworking operations and in industries where environmental regulations are strict. Before the development of modern MWFs, vegetable oils were one of the most common lubricants used for metalworking tools. The use of vegetable oils can be traced back to ancient civilizations such as Egypt, Greece, and Rome, where olive oil was commonly used to lubricate metal tools and weapons.

7.7K
19 Apr 2023

Topic Review

Nose Ring (Animal)

A nose ring is inserted into the nose of an animal. Nose rings are used to control bulls and occasionally cows, and to help wean young cattle by preventing suckling. Nose rings are used on pigs to discourage rooting. Some nose rings are installed through a pierced hole in the nasal septum or rim of the nose and remain there, while others are temporary tools.

7.7K
03 Nov 2022

Topic Review

Role-Playing Games

Role-Playing Games may be defined as a system for creating stories based on rules. They allow a group of players and a game director (also known as Game Master or Narrator) to participate and interact using their imagination to determine what could happen. There are different kinds of Role-Playing Games (RPGs) that relate to video games and online video games. The original RPGs, sometimes called tabletop RPGs or pen-and-paper RPGs, were the starting point of their digital relatives, and used mainly speech and imagination; however, technology may be used in some cases for communication. RPGs that are played by writing posts in forums or sending emails are called Play by Post (PbP). Some RPGs even require live interaction, similar to theater representations; these are called Live Action Role Play (LARP).

7.7K
17 Dec 2021

Topic Review

Face with Tears of Joy Emoji

thumb|Appearance in the EmojiOne emoji set|167x167px Face with Tears of Joy (😂) is an emoji featuring a jovial face laughing, while also crying out tears. It can also be used for joking and teasing. It is the most commonly used emoji on social media websites such as Facebook, Snapchat, Twitter and Instagram. The emoji is also variously known as the lol emoji, joy emoji, laughing emoji or the laughing crying emoji.

7.7K
09 Nov 2022

Topic Review

2010 Flash Crash

The May 6, 2010, Flash Crash, also known as the Crash of 2:45, the 2010 Flash Crash or simply the Flash Crash, was a United States trillion-dollar stock market crash, which started at 2:32 p.m. EDT and lasted for approximately 36 minutes.:1 Stock indexes, such as the S&P 500, Dow Jones Industrial Average and Nasdaq Composite, collapsed and rebounded very rapidly. The Dow Jones Industrial Average had its second biggest intraday point drop (from the opening) up to that point, plunging 998.5 points (about 9%), most within minutes, only to recover a large part of the loss. It was also the second-largest intraday point swing (difference between intraday high and intraday low) up to that point, at 1,010.14 points. The prices of stocks, stock index futures, options and exchange-traded funds (ETFs) were volatile, thus trading volume spiked.:3 A CFTC 2014 report described it as one of the most turbulent periods in the history of financial markets.:1 When new regulations put in place following the 2010 Flash Crash proved to be inadequate to protect investors in the August 24, 2015 flash crash—"when the price of many ETFs appeared to come unhinged from their underlying value"—ETFs were put under greater scrutiny by regulators and investors. On April 21, 2015, nearly five years after the incident, the U.S. Department of Justice laid "22 criminal counts, including fraud and market manipulation" against Navinder Singh Sarao, a trader. Among the charges included was the use of spoofing algorithms; just prior to the Flash Crash, he placed thousands of E-mini S&P 500 stock index futures contracts which he planned on canceling later. These orders amounting to about "$200 million worth of bets that the market would fall" were "replaced or modified 19,000 times" before they were canceled. Spoofing, layering, and front running are now banned. The Commodity Futures Trading Commission (CFTC) investigation concluded that Sarao "was at least significantly responsible for the order imbalances" in the derivatives market which affected stock markets and exacerbated the flash crash. Sarao began his alleged market manipulation in 2009 with commercially available trading software whose code he modified "so he could rapidly place and cancel orders automatically." Traders Magazine journalist, John Bates, argued that blaming a 36-year-old small-time trader who worked from his parents' modest stucco house in suburban west London for sparking a trillion-dollar stock market crash is a little bit like blaming lightning for starting a fire" and that the investigation was lengthened because regulators used "bicycles to try and catch Ferraris." Furthermore, he concluded that by April 2015, traders can still manipulate and impact markets in spite of regulators and banks' new, improved monitoring of automated trade systems. As recently as May 2014, a CFTC report concluded that high-frequency traders "did not cause the Flash Crash, but contributed to it by demanding immediacy ahead of other market participants.":1 Some recent peer-reviewed research shows that flash crashes are not isolated occurrences, but have occurred quite often. Gao and Mizrach studied US equities over the period of 1993–2011. They show that breakdowns in market quality (such as flash crashes) have occurred in every year they examined and that, apart from the financial crisis, such problems have declined since the introduction of Reg NMS. They also show that 2010, while infamous for the Flash Crash, was not a year with an inordinate number of breakdowns in market quality.

7.7K
30 Nov 2022

Topic Review

Parallel Processing (Psychology)

In psychology, parallel processing is the ability of the brain to simultaneously process incoming stimuli of differing quality. Parallel processing is associated with the visual system in that the brain divides what it sees into four components: color, motion, shape, and depth. These are individually analyzed and then compared to stored memories, which helps the brain identify what you are viewing. The brain then combines all of these into the field of view that then seen and comprehended. Parallel processing has been linked, by some experimental psychologists, to the stroop effect. This is a continual and seamless operation. For example, if one is standing between two different groups of people who are simultaneously carrying on two different conversations, one may be able to pick up only some information of both conversation at the same time.

7.7K
02 Dec 2022

Topic Review

Commune (Model of Government)

The commune, as a model of government, is generally advocated by some communists, revolutionary socialists, and anarchists. Communes are an organizational community with social cohesion derived from a shared culture. As a governing community, a commune often entails some degree of local governance, communal ownership, and cultural cohesion. However, models that do not include all three aspects may still be described as communes. At its core, a commune is just an organization which creates social conditions that prioritize the primacy of the collective over the individual. Many different forms of commune-based governments are possible, such as a local and sovereign community which is both a microstate and a nation-state, a federated commune which lacks a degree of sovereignty under the rule of a larger state, or a larger national community which focuses more on aspects of communal ownership rather than communal governance.

7.7K
09 Nov 2022

Topic Review

Dihedral (Aeronautics)

In aeronautics, dihedral is the angle between the left and right wings (or tail surfaces) of an aircraft. "Dihedral" is also used to describe the effect of sideslip on the rolling of the aircraft. Dihedral angle is the upward angle from horizontal of the wings or tailplane of a fixed-wing aircraft. "Anhedral angle" is the name given to negative dihedral angle, that is, when there is a downward angle from horizontal of the wings or tailplane of a fixed-wing aircraft. Dihedral angle has a strong influence on dihedral effect, which is named after it. Dihedral effect is the amount of roll moment produced in proportion to the amount of sideslip. Dihedral effect is a critical factor in the stability of an aircraft about the roll axis (the spiral mode). It is also pertinent to the nature of an aircraft's Dutch roll oscillation and to maneuverability about the roll axis. Longitudinal dihedral is a comparatively obscure term related to the pitch axis of an airplane. It is the angle between the zero-lift axis of the wing and the zero-lift axis of the horizontal tail. Longitudinal dihedral can influence the nature of controllability about the pitch axis and the nature of an aircraft's phugoid-mode oscillation. When the term "dihedral" (of an aircraft) is used by itself it is usually intended to mean "dihedral angle". However, context may otherwise indicate that "dihedral effect" is the intended meaning.

7.7K
27 Oct 2022

Topic Review

Hegemony (UK: /hɪˈɡɛməni, hɪˈdʒɛməni/, US: /hɪˈdʒɛməni/ (pronunciation (help·info)) or /ˈhɛdʒəˌmoʊni/) is the political, economic, or military predominance or control of one state over others. In Ancient Greece (8th century BC – 6th century AD), hegemony denoted the politico-military dominance of a city-state over other city-states. The dominant state is known as the hegemon. In the 19th century, hegemony came to denote the "Social or cultural predominance or ascendancy; predominance by one group within a society or milieu". Later, it could be used to mean "a group or regime which exerts undue influence within a society". Also, it could be used for the geopolitical and the cultural predominance of one country over others, from which was derived hegemonism, as in the idea that the Great Powers meant to establish European hegemony over Africa, Asia and Latin America. In cultural imperialism, the leader state dictates the internal politics and the societal character of the subordinate states that constitute the hegemonic sphere of influence, either by an internal, sponsored government or by an external, installed government. In international relations theory, hegemony denotes a situation of (i) great material asymmetry in favour of one state, that has (ii) enough military power to systematically defeat any potential contester in the system, (iii) controls the access to raw materials, natural resources, capital and markets, (iv) has competitive advantages in the production of value added goods, (v) generates an accepted ideology reflecting this status quo; and (vi) is functionally differentiated from other states in the system, being expected to provide certain public goods such as security, or commercial and financial stability. The Marxist theory of cultural hegemony, associated particularly with Antonio Gramsci, is the idea that the ruling class can manipulate the value system and mores of a society, so that their view becomes the world view (Weltanschauung): in Terry Eagleton's words, "Gramsci normally uses the word hegemony to mean the ways in which a governing power wins consent to its rule from those it subjugates". In contrast to authoritarian rule, cultural hegemony "is hegemonic only if those affected by it also consent to and struggle over its common sense".

7.6K
10 Nov 2022

Biography

James Arthur Gosling, OC (born May 19, 1955) is a Canadian computer scientist, best known as the founder and lead designer behind the Java programming language.[1] James Gosling received a Bachelor of Science from the University of Calgary [2] and his M.A. and Ph.D. from Carnegie Mellon University, all in computer science.[3][4][5] He wrote a version of Emacs called Gosling Emacs (Gosmacs) wh

7.6K
24 Nov 2022

Topic Review

The Intelligent Reflecting Surface

The Intelligent Reflecting Surface (IRS) is a revolutionary technology to improve the performance of wireless data transmission systems. In particular, the wireless signal transmission environment is reconfigured by jointly adjusting a large number of small reflective units

7.6K
08 Apr 2022

Topic Review

Jojoba is a widely used medicinal plant that is cultivated worldwide. Its seeds and oil have a long history of use in folklore to treat various ailments, such as skin and scalp disorders, superficial wounds, sore throat, obesity, and cancer; for improvement of liver functions, enhancement of immunity, and promotion of hair growth. Extensive studies on Jojoba oil showed a wide range of pharmacological applications, including antioxidant, anti-acne and antipsoriasis, anti-inflammatory, antifungal, antipyretic, analgesic, antimicrobial, and anti-hyperglycemia activities. In addition, Jojoba oil is widely used in the pharmaceutical industry, especially in cosmetics for topical, transdermal, and parenteral preparations. Jojoba oil also holds value in the industry as an anti-rodent, insecticides, lubricant, surfactant, and a source for the production of bioenergy. Jojoba oil is considered among the top-ranked oils due to its wax, which constitutes about 98% (mainly wax esters, few free fatty acids, alcohols, and hydrocarbons). In addition, sterols and vitamins with few triglyceride esters, flavonoids, phenolic and cyanogenic compounds are also present.

7.6K
03 Jun 2021

Topic Review

The Younger Dryas (around 12,900 to 11,700 years BP) was a return to glacial conditions after the Late Glacial Interstadial, which temporarily reversed the gradual climatic warming after the Last Glacial Maximum (LGM) started receding around 20,000 BP. It is named after an indicator genus, the alpine-tundra wildflower Dryas octopetala, as its leaves are occasionally abundant in late glacial, often minerogenic-rich sediments, such as the lake sediments of Scandinavia. Physical evidence of a sharp decline in temperature over most of the Northern Hemisphere has been discovered by geological research. This temperature change occurred at the end of what the earth sciences refer to as the Pleistocene epoch and immediately before the current, warmer Holocene epoch. In archaeology, this time frame coincides with the final stages of the Upper Paleolithic in many areas. The Younger Dryas was the most recent and longest of several interruptions to the gradual warming of the Earth's climate since the severe LGM, about 27,000 to 24,000 years BP. The change was relatively sudden, taking place in decades, and it resulted in a decline of temperatures in Greenland by 4 to 10°C (7.2 to 18°F) and advances of glaciers and drier conditions, over much of the temperate Northern Hemisphere. It is thought to have been caused by a decline in the strength of the Atlantic meridional overturning circulation, which transports warm water from the Equator towards the North Pole, in turn thought to have been caused by an influx of fresh, cold water from North America to the Atlantic. The Younger Dryas was a period of climatic change, but the effects were complex and variable. In the Southern Hemisphere and some areas of the Northern Hemisphere, such as southeastern North America, a slight warming occurred.

7.6K
14 Oct 2022

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