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Topic Review
Prince of Wales's Feathers
Template:Infobox Coat of arms The Prince of Wales's feathers is the heraldic badge of the Prince of Wales. It consists of three white ostrich feathers emerging from a gold coronet. A ribbon below the coronet bears the motto Ich dien (German: [ɪç ˈdiːn], "I serve"). As well as being used in royal heraldry, the badge is sometimes used to symbolise Wales, particularly in Welsh rugby union and Welsh regiments of the British Army.
  • 6.2K
  • 27 Nov 2022
Topic Review
Dunkleosteus
Dunkleosteus is an extinct genus of large armored, jawed fishes that existed during the Late Devonian period, about 382–358 million years ago. It consists of ten species, some of which are among the largest placoderms to have ever lived: D. terrelli, D. belgicus, D. denisoni, D. marsaisi, D. magnificus, D. missouriensis, D. newberryi, D. amblyodoratus, and D. raveri. The largest and most well known species is D. terrelli, which grew up to 8.79 m (28.8 ft) long and 4 t (4.4 short tons) in weight. Dunkleosteus could quickly open and close its jaw, like modern-day suction feeders, and had a bite force of 6,000 N (612 kgf; 1,349 lbf) at the tip and 7,400 N (755 kgf; 1,664 lbf) at the blade edge. Numerous fossils of the various species have been found in North America, Poland , Belgium, and Morocco.
  • 6.2K
  • 16 Nov 2022
Topic Review
Causes of Transsexuality
The study of the causes of transsexuality investigates gender identity formation of transgender people, especially those who are transsexual. Transgender people have a gender identity that does not match their assigned sex, often resulting in gender dysphoria. The causes of transsexuality have been studied for decades. The most studied factors are biological, especially brain structure differences in relation to biology and sexual orientation. Environmental factors have also been proposed. Transgender brain studies, especially those on trans women who are sexually attracted to women (gynephilic), and those on trans men who are sexually attracted to men (androphilic), are limited, as they include a small number of tested individuals. The available research indicates that the brain structure of androphilic trans women with early-onset gender dysphoria is closer to the brain structure of cisgender women's and less like cisgender men's. It also reports that both androphilic trans women and trans women with late-onset gender dysphoria who are gynephilic have different brain phenotypes, and that gynephilic trans women differ from both cisgender female and male controls in non-dimorphic brain areas. Cortical thickness, which is generally thicker in cisgender women's brains than in cisgender men's brains, may also be thicker in trans women's brains, but is present in a different location to cisgender women's brains. For trans men, research indicates that those with early-onset gender dysphoria and who are gynephilic have brains that generally correspond to their assigned sex, but that they have their own phenotype with respect to cortical thickness, subcortical structures, and white matter microstructure, especially in the right hemisphere. Hormone use can also affect transgender people's brain structure; it can cause transgender women's brains to become closer to those of cisgender women, and morphological increments observed in the brains of trans men might be due to the anabolic effects of testosterone. Twin studies suggest that there are likely genetic causes of transsexuality, although the precise genes involved are not fully understood. One study published in the International Journal of Transgender Health found that 20% of identical twin pairs in which at least one twin was trans were both trans, compared to only 2.6% of non-identical twins who were raised in the same family at the same time, but were not genetically identical. Ray Blanchard created a taxonomy of male-to-female transsexualism that proposes two distinct etiologies for androphilic and gynephilic individuals that has become controversial, supported by J. Michael Bailey, Anne Lawrence, James Cantor and others, but opposed by Charles Allen Moser, Julia Serano, and the World Professional Association for Transgender Health.
  • 6.2K
  • 20 Oct 2022
Topic Review
Topical Antifungal-Corticosteroid Combinations
A broad range of topical antifungal formulations containing miconazole or terbinafine as actives are commonly used as efficacious choices for combating fungal skin infections. Their many benefits, owing to their specific mechanism of action, include their ability to target the site of infection, enhance treatment efficacy and reduce the risk of systemic side effects. Their proven efficacy, and positioning in the treatment of fungal skin infections, is enhanced by high patient compliance, especially when appropriate vehicles such as creams, ointments and gels are used.
  • 6.2K
  • 18 Aug 2022
Topic Review
Iranian Plateau
The Iranian Plateau or the Persian Plateau is a geological feature in Central Asia, South Asia, and Western Asia. It is the part of the Eurasian Plate wedged between the Arabian and Indian plates, situated between the Zagros Mountains to the west, the Caspian Sea and the Kopet Dag to the north, the Armenian Highlands and the Caucasus Mountains in the northwest, the Strait of Hormuz and the Persian Gulf to the south and the Indo-Gangetic Plain to the east in Indian subcontinent. As a historical region, it includes Parthia, Media, Persis, the heartlands of Iran and some of the previous territories of Greater Iran. The Zagros Mountains form the plateau's western boundary, and its eastern slopes may be included in the term. The Encyclopædia Britannica excludes "lowland Khuzestan" explicitly and characterizes Elam as spanning "the region from the Mesopotamian Plain to the Iranian Plateau". From the Caspian in the northwest to Balochistan in the south-east, the Iranian Plateau extends for close to 2,000 km. It encompasses the greater part of Iran, all of Afghanistan, and Pakistan west of the Indus River containing some 3,700,000 square kilometres (1,400,000 sq mi). In spite of being called a "plateau", it is far from flat but contains several mountain ranges, the highest peak being Damavand in the Alborz at 5610 m, and the Dasht-e Lut east of Kerman in Central Iran falling below 300 m.
  • 6.2K
  • 22 Nov 2022
Topic Review
Wine Tourism
Nowadays, wine has become an important beverage that is increasingly being consumed more frequently all over the world, and its production and marketing has received increasing attention from consumers, specialists, and producers. As a result, the growing importance of wine tourism for many destinations and the role of this type of tourism in supporting local economies is now beginning to be understood. It has also been highlighted that wine tourism can play a significant role in the development of tourism by contributing to the economic and social support of local regions and communities. Wine is one of the ingredients of people's journeys, and journeys dedicated to wine-producing areas have led to the tourism product known as wine tourism.
  • 6.2K
  • 18 Apr 2022
Topic Review
Dot-Com Bubble
The dot-com bubble (also known as the dot-com boom, the tech bubble, and the Internet bubble) was a historic economic bubble and period of excessive speculation that occurred roughly from 1995 to 2000, a period of extreme growth in the usage and adaptation of the Internet. The Nasdaq Composite stock market index, which included many Internet-based companies, peaked in value on March 10, 2000 before crashing. The burst of the bubble, known as the dot-com crash, lasted from March 11, 2000 to October 9, 2002. During the crash, many online shopping companies, such as Pets.com, Webvan, and Boo.com, as well as communication companies, such as Worldcom, NorthPoint Communications and Global Crossing failed and shut down. Others, such as Cisco, whose stock declined by 86%, and Qualcomm, lost a large portion of their market capitalization but survived, and some companies, such as eBay and Amazon.com, declined in value but recovered quickly.
  • 6.2K
  • 01 Nov 2022
Topic Review
Biochemistry of Hydrogen Peroxide
Hydrogen Peroxide (H2O2) is the nonionized 2-electron reduction product of unstable molecular oxygen (O2), which plays a central role in maintaining the redox cycle of living cells.
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  • 10 Jan 2022
Topic Review
Self-confidence
The concept of self-confidence is commonly used as self-assurance in one's personal judgment, ability, power, etc. One's self confidence increases from experiences of having satisfactorily completed particular activities. It is a positive belief that in the future one can generally accomplish what one wishes to do. Self-confidence is not the same as self-esteem, which is an evaluation of one's own worth, whereas self-confidence is more specifically trust in one's ability to achieve some goal, which one meta-analysis suggested is similar to generalization of self-efficacy. Abraham Maslow and many others after him have emphasized the need to distinguish between self-confidence as a generalized personality characteristic, and self-confidence with respect to a specific task, ability or challenge (i.e. self-efficacy). Self-confidence typically refers to general self-confidence. This is different from self-efficacy, which psychologist Albert Bandura has defined as a “belief in one’s ability to succeed in specific situations or accomplish a task” and therefore is the term that more accurately refers to specific self-confidence. Psychologists have long noted that a person can possess self-confidence that he or she can complete a specific task (self-efficacy) (e.g. cook a good meal or write a good novel) even though they may lack general self-confidence, or conversely be self-confident though they lack the self-efficacy to achieve a particular task (e.g. write a novel). These two types of self-confidence are, however, correlated with each other, and for this reason can be easily conflated.
  • 6.2K
  • 18 Oct 2022
Topic Review
Straight-Three Engine
A straight-three engine, also known as an inline-triple, or inline-three (abbreviated I3 or L3), is a reciprocating piston internal combustion engine with three cylinders arranged in a straight line or plane, side by side.
  • 6.2K
  • 31 Oct 2022
Topic Review
Partition Problem
In number theory and computer science, the partition problem, or number partitioning, is the task of deciding whether a given multiset S of positive integers can be partitioned into two subsets S1 and S2 such that the sum of the numbers in S1 equals the sum of the numbers in S2. Although the partition problem is NP-complete, there is a pseudo-polynomial time dynamic programming solution, and there are heuristics that solve the problem in many instances, either optimally or approximately. For this reason, it has been called "the easiest hard problem". There is an optimization version of the partition problem, which is to partition the multiset S into two subsets S1, S2 such that the difference between the sum of elements in S1 and the sum of elements in S2 is minimized. The optimization version is NP-hard, but can be solved efficiently in practice.
  • 6.2K
  • 10 Oct 2022
Topic Review
Visual-SLAM Algorithms
The visual-based simultaneous localization and mapping (SLAM) techniques use one or more cameras in the sensor system, receiving 2D images as the source of information. In general, the visual-based SLAM algorithms are divided into three main threads: initialization, tracking, and mapping.
  • 6.2K
  • 23 Mar 2022
Topic Review
Laser Absorption Spectroscopy
Laser absorption spectroscopy (LAS) is an absorption spectroscopic method that employs a laser as the light source and measures the chemical concentration based on detection of a variation of laser beam intensity after transmission along the optical path. 
  • 6.2K
  • 10 Sep 2020
Topic Review
Correlation and Dependence
In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. In the broadest sense correlation is any statistical association, though it commonly refers to the degree to which a pair of variables are linearly related. Familiar examples of dependent phenomena include the correlation between the height of parents and their offspring, and the correlation between the price of a good and the quantity the consumers are willing to purchase, as it is depicted in the so-called demand curve. Correlations are useful because they can indicate a predictive relationship that can be exploited in practice. For example, an electrical utility may produce less power on a mild day based on the correlation between electricity demand and weather. In this example, there is a causal relationship, because extreme weather causes people to use more electricity for heating or cooling. However, in general, the presence of a correlation is not sufficient to infer the presence of a causal relationship (i.e., correlation does not imply causation). Formally, random variables are dependent if they do not satisfy a mathematical property of probabilistic independence. In informal parlance, correlation is synonymous with dependence. However, when used in a technical sense, correlation refers to any of several specific types of mathematical operations between the tested variables and their respective expected values. Essentially, correlation is the measure of how two or more variables are related to one another. There are several correlation coefficients, often denoted [math]\displaystyle{ \rho }[/math] or [math]\displaystyle{ r }[/math], measuring the degree of correlation. The most common of these is the Pearson correlation coefficient, which is sensitive only to a linear relationship between two variables (which may be present even when one variable is a nonlinear function of the other). Other correlation coefficients – such as Spearman's rank correlation – have been developed to be more robust than Pearson's, that is, more sensitive to nonlinear relationships. Mutual information can also be applied to measure dependence between two variables.
  • 6.2K
  • 14 Oct 2022
Topic Review
Solar Power Plants in Iran
The world’s electricity generation has increased with renewable energy technologies such as solar (solar power plant), wind energy (wind turbines), heat energy, and even ocean waves. Iran is in the best condition to receive solar radiation due to its proximity to the equator (25.2969° N). In 2020, Iran was able to supply only 900 MW (about 480 solar power plants and 420 MW home solar power plants) of its electricity demand from solar energy, which is very low compared to the global average. Yazd, Fars, and Kerman provinces are in the top ranks of Iran, with the production of approximately 68, 58, and 47 MW using solar energy, respectively. Iran also has a large area of vacant land for the construction of solar power plants.
  • 6.2K
  • 07 Jan 2022
Topic Review
Nomadic Empire
Nomadic empires, sometimes also called steppe empires, Central or Inner Asian empires, were the empires erected by the bow-wielding, horse-riding, nomadic people in the Eurasian Steppe, from classical antiquity (Scythia) to the early modern era (Dzungars). They are the most prominent example of non-sedentary polities. Some nomadic empires consolidated by establishing a capital city inside a conquered sedentary state and then exploiting the existing bureaucrats and commercial resources of that non-nomadic society. In such a scenario, the originally nomadic dynasty may become culturally assimilated to the culture of the occupied nation before it is ultimately overthrown. Ibn Khaldun (1332–1406) described a similar cycle on a smaller scale in 1377 in his Asabiyyah theory. Historians of the early medieval period may refer to these polities as "khanates" (after khan, the title of their rulers). After the Mongol conquests of the 13th century the term orda ("horde") also came into use — as in "Golden Horde".
  • 6.2K
  • 25 Nov 2022
Topic Review
Rudra
Rudra (/ˈrʊdrə/; Sanskrit: रुद्र) is a Rigvedic deity, associated with wind or storm and the hunt. One translation of the name is "the roarer". In the Rigveda, Rudra has been praised as the "mightiest of the mighty". Rudra is the personification of 'terror'. Depending up on the periodic situation, Rudra can be meant as the most severe roarer/howler (could be a hurricane or tempest) or the most frightening one. The Shri Rudram hymn from the Yajurveda is dedicated to Rudra, and is important in the Saivism sect. The Hindu god Shiva shares several features with the Rudra: the theonym Shiva originated as an epithet of Rudra, the adjective shiva ("kind") being used euphemistically of Rudra, who also carries the epithet Aghora, Abhayankar ("extremely calm [sic] non terrifying"). Usage of the epithet came to exceed the original theonym by the post-Vedic period (in the Sanskrit Epics), and the name Rudra has been taken as a synonym for the god Shiva and the two names are used interchangeably.
  • 6.1K
  • 25 Nov 2022
Topic Review
Container Shipping Supply Chain
Container shipping supply chain (CSSC) consists of several key stakeholders such as the shipper, freight forwarder, shipping line, port/terminal operator, inland carrier, and intermodal terminal/depot operator, who are working together to transport containerized cargo by different transport vehicles (e.g., vessels, trains, and trucks) and handle the containers by various types of handling equipment and facilities (e.g., terminals, cranes, trailers, wagons, lifters, and depots) from origin to destination along the entire end-to-end supply chain.
  • 6.1K
  • 05 Jul 2021
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.
  • 6.1K
  • 27 Oct 2022
Topic Review
The Photosynthetic Apparatus of Plants
Chlorophylls together with carotenoids, serve, noncovalently bound to specific apoproteins, as principal light-harvesting and energy-transforming pigments in oxygenic photosynthetic organisms, including plants.
  • 6.1K
  • 10 Jun 2021
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