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Topic Review
Iris (Anatomy)
In humans and most mammals and birds, the iris (plural: irides or irises) is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina. Eye color is defined by that of the iris. In optical terms, the pupil is the eye's aperture, while the iris is the diaphragm.
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  • 11 Oct 2022
Topic Review
Watson (Computer)
Watson is a question-answering computer system capable of answering questions posed in natural language, developed in IBM's DeepQA project by a research team led by principal investigator David Ferrucci. Watson was named after IBM's founder and first CEO, industrialist Thomas J. Watson. The computer system was initially developed to answer questions on the quiz show Jeopardy! and, in 2011, the Watson computer system competed on Jeopardy! against champions Brad Rutter and Ken Jennings, winning the first place prize of $1 million. In February 2013, IBM announced that Watson software system's first commercial application would be for utilization management decisions in lung cancer treatment at Memorial Sloan Kettering Cancer Center, New York City, in conjunction with WellPoint (now Anthem). In 2013, Manoj Saxena, IBM Watson's business chief said that 90% of nurses in the field who use Watson now follow its guidance.
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  • 19 Oct 2022
Topic Review
List of Aircraft in the Smithsonian Institution
The List of aircraft in the Smithsonian Institution includes aircraft exhibited in the Smithsonian Institution's National Air and Space Museum, Steven F. Udvar-Hazy Center, and the Paul E. Garber Preservation, Restoration, and Storage Facility. The Smithsonian Institution's collection of aircraft and spacecraft is the largest on display in the world.
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  • 21 Oct 2022
Topic Review
Orrery
An orrery is a mechanical model of the Solar System that illustrates or predicts the relative positions and motions of the planets and moons, usually according to the heliocentric model. It may also represent the relative sizes of these bodies; however, since accurate scaling is often not practical due to the actual large ratio differences, a subdued approximation may be used instead. Though the Greeks had working planetaria, the first orrery that was a planetarium of the modern era was produced in 1704, and one was presented to Charles Boyle, 4th Earl of Orrery – hence the name. They are typically driven by a clockwork mechanism with a globe representing the Sun at the centre, and with a planet at the end of each of the arms.
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  • 04 Nov 2022
Topic Review
Detection of Beta-Glucan
This entry provides a comprehensive review of the current literature about biological properties and available methods for the detection of beta-glucans. It shares the experience of the Nanotechnology Characterization Laboratory with the detection of beta-glucans in nanotechnology-based drug products. This entry summarizes and discusses five different approaches currently applied for the data interpretation of beta-glucan tests with respect to the acceptability (or lack thereof) of the beta-glucan levels in pharmaceutical products.
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  • 03 Nov 2020
Topic Review
Computus
The computus (Latin for 'computation') is a calculation that determines the calendar date of Easter.:xviii Easter is traditionally celebrated on the first Sunday after the Paschal full moon, which is the first full moon on or after 21 March (an approximation of the March equinox). Determining this date in advance requires a correlation between the lunar months and the solar year, while also accounting for the month, date, and weekday of the calendar.:xviii-xx The calculations produce different results depending on whether the Julian calendar or the Gregorian calendar is used. In late antiquity, it was feasible for the entire Christian church to receive the date of Easter each year through an annual announcement from the Pope. By the early third century, however, communications had deteriorated to the point that the church put great value in a system that would allow the clergy to independently and consistently determine the date for themselves.:xx Additionally, the church wished to eliminate dependencies on the Hebrew calendar, by deriving Easter directly from the vernal equinox.:xxxvi In The Reckoning of Time (725), Bede uses computus as a general term for any sort of calculation, although he refers to the Easter cycles of Theophilus as a "Paschal computus." By the end of the 8th century, computus came to refer specifically to the calculation of time.
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  • 15 Nov 2022
Topic Review
Jiles–Atherton Model
The Jiles–Atherton model of magnetic hysteresis was introduced in 1984 by David Jiles and D. L. Atherton. This is one of the most popular models of magnetic hysteresis. Its main advantage is the fact that this model enables connection with physical parameters of the magnetic material. Jiles–Atherton model enables calculation of minor and major hysteresis loops. The original Jiles–Atherton model is suitable only for isotropic materials. However, an extension of this model presented by Ramesh et al. and corrected by Szewczyk enables the modeling of anisotropic magnetic materials.
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  • 02 Nov 2022
Topic Review
World
The World is the Earth and all life on it, including human civilization. In a philosophical context, the "world" is the whole of the physical Universe, or an ontological world (the "world" of an individual). In a theological context, the world is the material or the profane sphere, as opposed to the celestial, spiritual, transcendent or sacred spheres. "End of the world" scenarios refer to the end of human history, often in religious contexts. Human history is commonly understood as the history of humanity spanning the major geopolitical developments of about five millennia, from the first civilizations to the present. In terms such as world religion, world language, world government, and world war, the term world suggests an international or intercontinental scope without necessarily implying participation of every part of the world. The world population is the sum of all human populations at any time; similarly, the world economy is the sum of the economies of all societies or countries, especially in the context of globalization. Terms such as "world championship", "gross world product", and "world flags" imply the sum or combination of all sovereign states.
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  • 17 Nov 2022
Topic Review
Aluminum-Fuel-Based Energy Conversion Systems
Metallic aluminum is widely used in propellants, energy-containing materials, and batteries due to its high energy density. In addition to burning in the air, aluminum can react with water to generate hydrogen. Aluminum is carbon-free and the solid-phase products can be recycled easily after the reaction. Micron aluminum powder is stable in the air and enables global trade. Aluminum metal is considered to be a viable recyclable carrier for clean energy.
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  • 05 Jan 2023
Topic Review
Pomegranate Juice for CYP3A4- and CYP2C9-Mediated Drugs Metabolism
The Punica granatum L. (pomegranate) fruit juice contains large amounts of polyphenols, mainly tannins such as ellagitannin, punicalagin, and punicalin, and flavonoids such as anthocyanins, flavan-3-ols, and flavonols. These constituents have high antioxidant, anti-inflammatory, anti-diabetic, anti-obesity, and anticancer activities. Because of these activities, many patients may consume pomegranate juice (PJ) with or without their doctor’s knowledge. This may raise any significant medication errors or benefits because of food-drug interactions that modulate the drug’s pharmacokinetics or pharmacodynamics. 
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  • 18 May 2023
Topic Review
Rockfall
A rockfall is defined as the “detachment, fall, rolling, and bouncing of rock fragments. It may occur singly or in clusters, but there is little dynamic interaction between the most mobile moving fragments, which interact mainly with the substrate (path)".
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  • 04 Aug 2021
Topic Review
AI Art
Artists have been working with artificial intelligence (AI) since the 1970s. They comprised a minuscule enclave within the early computer art community throughout the 1970s and 1980s and were largely unnoticed by the mainstream artworld and broader public. In the 1990s and 2000s, more artists got involved with AI and produced installations that question the meaning of agency, creativity, and expression. Since the 2000s, AI art diversified into generative and interactive approaches that involved statistical methods, natural language processing, pattern recognition, and computer vision algorithms. The increasing affordance of multilayered machine learning architectures, as well as the raising socio-political impact of AI, have facilitated the further expansion of AI art in the second half of the 2010s. The topics, methodologies, presentational formats, and implications of contemporary AI art are closely related to, and affected by, AI science research, development, and commercial application. The poetic scope of AI art is primarily informed by the various phenomenological aspects of sub-symbolic machine learning. It comprises creative strategies that explore the epistemological boundaries and artifacts of AI architectures; sample the latent space of neural networks; aestheticize the AI data renderings; and critique the conceptual, existential, or socio-political consequences of corporate AI; a few works criticize AI art itself. These strategies unfold in disparate practices ranging from popular and spectacular to tactical and experimental. The existing taxonomies or categorizations of AI art should be considered as provisory because of the creative dynamics and transdisciplinary character of the field. Similar to other computational art disciplines, AI art has had an ambivalent relationship with the mainstream artworld, marked by selective marginalization and occasional exploitation.
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  • 27 Jan 2022
Topic Review
Intersubjectivity
Intersubjectivity refers to the shared understanding and mutual agreement between individuals regarding their subjective experiences, perceptions, and interpretations of the world. It involves the recognition and validation of each other's perspectives, allowing for meaningful communication, cooperation, and collaboration based on common understanding and empathy. Intersubjectivity is essential for social interaction, interpersonal relationships, and the construction of shared meanings within society.
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  • 02 Feb 2024
Topic Review
Hinduism and Theosophy
Hinduism is regarded by modern Theosophy as one of the main sources of "esoteric wisdom" of the East. The Theosophical Society was created in a hope that Asian philosophical-religious ideas "could be integrated into a grand religious synthesis." Prof. Antoine Faivre wrote that "by its content and its inspiration" the Theosophical Society is greatly dependent on Eastern traditions, "especially Hindu; in this, it well reflects the cultural climate in which it was born." A Russian Indologist Alexander Senkevich noted that the concept of Helena Blavatsky's Theosophy was based on Hinduism. According to Encyclopedia of Hinduism, "Theosophy is basically a Western esoteric teaching, but it resonated with Hinduism at a variety of points."
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  • 21 Nov 2022
Topic Review
FireEye
FireEye is a privately held cybersecurity company headquartered in Milpitas, California. It has been involved in the detection and prevention of major cyber attacks. It provides hardware, software, and services to investigate cybersecurity attacks, protect against malicious software, and analyze IT security risks. FireEye was founded in 2004. Initially, it focused on developing virtual machines that would download and test internet traffic before transferring it to a corporate or government network. The company diversified over time, in part through acquisitions. In 2014, it acquired Mandiant, which provides incident response services following the identification of a security breach. FireEye went public in 2013. USAToday says FireEye "has been called in to investigate high-profile attacks against Target, JP Morgan Chase, Sony Pictures, Anthem and others".
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  • 18 Oct 2022
Topic Review
Pan-Islamism
Pan-Islamism (Arabic: الوحدة الإسلامية) is a political movement advocating the unity of Muslims under one Islamic country or state – often a caliphate – or an international organization with Islamic principles. Pan-Islamism was launched in Turkey at the end of the 19th century by Sultan Abdul-Hamid II for the purpose of combating the process of westernization and fostering the unification of Islam. Pan-Islamism differentiates itself from pan-nationalistic ideologies, for example Pan-Arabism, by seeing the ummah (Muslim community) as the focus of allegiance and mobilization, excluding ethnicity and race as primary unifying factors. The major leaders of the Pan-Islamist movement were the triad of Jamal al-Din Afghani (1839 - 1897), Muhammad Abduh (1849 - 1905) and Sayyid Rashid Rida (1865 - 1935); who were active in anti-colonial efforts to confront European penetration of Muslim lands. They also sought to strengthen Islamic unity, which they believed to be the strongest force to mobilize Muslims against imperial domination. Following Ibn Saud's conquest of Arabian Peninsula; pan-Islamism would be bolstered across the Islamic World. During the second half of the twentieth century; pan-Islamists would compete against secular nationalist ideologies in the Arab World such as Nasserism.
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  • 15 Nov 2022
Topic Review
Ch’orti’ Language
The Ch'orti' language (sometimes also Chorti) is a Mayan language, spoken by the indigenous Maya people who are also known as the Ch'orti' or Ch'orti' Maya. Ch'orti' is a direct descendant of the Classic Maya language in which many of the pre-Columbian inscriptions using the Maya script were written. This Classic Maya language is also attested in a number of inscriptions made in regions whose inhabitants most likely spoke a different Mayan language variant, including the ancestor of Yukatek Maya. Ch'orti' is the modern version of the ancient Mayan language Ch'olan (which was actively used and most popular between the years of A.D 250 and 850).
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  • 15 Nov 2022
Topic Review
Techno-Economic and Life Cycle Cost Analysis
The techno-economic analysis (TEA) and the life cycle cost analysis (LCCA) are the most widely used approaches for modeling and calculating processes’ economic impacts. A simulation-based TEA is a cost-benefit analysis that simultaneously considers technical and economic factors. In addition, the method facilitates the development of the entire project and provides a systematic approach for examining the interrelationships between economic and technological aspects. When it comes to economic studies, it is intimately bonded with uncertainty. There are numerous uncertainty sources, classified in various ways. The uncertainty reflects “an inability to determine the precise value of one or more parameters affecting a system.” The variability refers to the different values a given parameter may take. This implies that a probability density function (PDF), for instance, can be employed to estimate and quantify the variability of a given parameter. The bias refers to “assumptions that skew an analysis in a certain direction while ignoring other legitimate alternatives, factors, or data.” 
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  • 21 Oct 2022
Topic Review Peer Reviewed
T’amar Bagrationi (1184–1210)
T’amar Bagrationi, Queen of Georgia (1184–1210). T’amar Bagrationi was the ninth monarch from the royal house of Bagrationis who ruled over the united Georgian Kingdom. She reigned as a co-monarch alongside her father, Giorgi III, from 1178, assuming full authority in 1184. During her reign, dynastic legitimacy necessitated the appearance of the monumental royal portraits displaying the monarch with immediate predecessors and heirs. T’amar’s gender required introduction of meticulous visual language that would re-gender her with all signs of a male ruler and justify her status and sole right to rule. This notion was embodied in her portraits that were carefully incorporated in the overall programmes of the churches. T’amar’s five monumental depictions survive where she is identified in inscriptions; two other monumental images are presumed to depict her. Of all the depictions, only one can be determined to have been commissioned directly by her. T’amar’s imagery relies on Byzantine elements and adheres to established Georgian models for the local royal portraiture; however, it also adopted sophisticated visual means that was aptly used for manifesting royal power and manipulating authority over the nobility. 
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  • 18 Aug 2022
Topic Review
Shuttle–Mir Program
The Shuttle–Mir Program was a collaborative space program between Russia and the United States, which involved American Space Shuttles visiting the Russian space station Mir, Russian cosmonauts flying on the shuttle, and an American astronaut flying aboard a Soyuz spacecraft to engage in long-duration expeditions aboard Mir. The project, sometimes called "Phase One", was intended to allow the United States to learn from Russian experience with long-duration spaceflight and to foster a spirit of cooperation between the two nations and their space agencies, the US National Aeronautics and Space Administration (NASA) and the Russian Federal Space Agency (Roskosmos). The project helped to prepare the way for further cooperative space ventures; specifically, "Phase Two" of the joint project, the construction of the International Space Station (ISS). The program was announced in 1993, the first mission started in 1994 and the project continued until its scheduled completion in 1998. Eleven Space Shuttle missions, a joint Soyuz flight and almost 1000 cumulative days in space for American astronauts occurred over the course of seven long-duration expeditions. During the four-year program, many firsts in spaceflight were achieved by the two nations, including the first American astronaut to launch aboard a Soyuz spacecraft, the largest spacecraft ever to have been assembled at that time in history, and the first American spacewalk using a Russian Orlan spacesuit. The program was marred by various concerns, notably the safety of Mir following a fire and a collision, financial issues with the cash-strapped Russian Space Program and worries from astronauts about the attitudes of the program administrators. Nevertheless, a large amount of science, expertise in space station construction and knowledge in working in a cooperative space venture was gained from the combined operations, allowing the construction of the ISS to proceed much more smoothly than would have otherwise been the case.
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  • 19 Oct 2022
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