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Topic Review

Biomechanics of Table Tennis

Table tennis is a popular recreational and competitive sports at all levels. Recent research on table tennis maneuvers identified the differences between playing levels and between maneuvers using parameters which included ball and racket speed, joint kinematics and kinetics, electromyography, and plantar pressure distribution. Different maneuvers underlined changes on body posture and lines of movement which were accommodated particularly by the racket face angle, trunk rotation, knee and elbow joint movements, and thus different contributions of muscles. Higher-level players produced ball and strike at higher accuracy and repeatability but not necessarily lead to higher speed. In addition, higher-level players utilize superior whole-body coordination and footwork to compromise between agility and stability for a quality strike. Strengthening shoulder and wrist muscles could enhance the speed of the strike while personalized training shall be considered since motor coordination and adaptation vary among individuals.

14.6K
29 Oct 2020

Topic Review

Criticism of Jehovah's Witnesses

Jehovah's Witnesses have received criticism from mainstream Christianity, members of the medical community, former members, and commentators regarding their beliefs and practices. The movement has been accused of doctrinal inconsistency and reversals, failed predictions, mistranslation of the Bible, harsh treatment of former members and autocratic and coercive leadership. Criticism has also focused on their rejection of blood transfusions, particularly in life-threatening medical situations, and claims that they have failed to report cases of sexual abuse to the authorities. Many of the claims are denied by Jehovah's Witnesses and some have also been disputed by courts and religious scholars.

14.6K
18 Nov 2022

Topic Review

Chief Justice of Pakistan

The chief justice of Pakistan (Urdu: منصف اعظم پاکستان) (initials as CJP) is the head of the court system of Pakistan (the judicature branch of government) and the chief judge of the Supreme Court of Pakistan. The officeholder is the senior most of 17 senior justices of the Supreme Court of Pakistan. The Federal Court of Pakistan was established by Governor-General Jinnah's Order in February 1948. Until 1956, the chief justice and senior justices were known by the title of 'Federal Judge', and the Federal Court of Pakistan operated out of a wing of the Lahore High Court, despite the federal capital's location in Karachi. The enactment of Pakistan's first constitution in March 1956 redesigned it as the 'Supreme Court of Pakistan.' The chief justice is the chief administrative officer of the country's court system and the highest judicial officer, ranking immediately above the chief justice of the Federal Shariat Court, and is responsible for supervising federal judicial policies, and conducting judicial business in the Supreme Court. Nomination for the appointment of the chief justice is made by the prime minister of Pakistan, and final appointments are confirmed by the president of Pakistan. Presiding over the oral arguments before the court, the chief justice has significant agenda-setting power over meetings of the Supreme Court. In modern tradition[clarification needed], the chief justice has the ceremonial duty of administering the oath of office of the president of Pakistan. The first chief justice was Sir Abdul Rashid. The current chief justice is Umar Ata Bandial; incumbent since 2 February 2022.

14.6K
21 Nov 2022

Topic Review

Muhammad Ibn Musa Al-Khwarizmi

Muḥammad ibn Mūsā al-Khwārizmī (Persian: محمد بن موسی خوارزمی‎, romanized: Moḥammad ben Musā Khwārazmi; c. 780 – c. 850), or al-Khwarizmi and formerly Latinized as Algorithmi, was a Persian polymath who produced vastly influential works in mathematics, astronomy, and geography. Around 820 CE he was appointed as the astronomer and head of the library of the House of Wisdom in Baghdad.:14 Al-Khwarizmi's popularizing treatise on algebra (The Compendious Book on Calculation by Completion and Balancing, c. 813–833 CE:171) presented the first systematic solution of linear and quadratic equations. One of his principal achievements in algebra was his demonstration of how to solve quadratic equations by completing the square, for which he provided geometric justifications.:14 Because he was the first to treat algebra as an independent discipline and introduced the methods of "reduction" and "balancing" (the transposition of subtracted terms to the other side of an equation, that is, the cancellation of like terms on opposite sides of the equation), he has been described as the father or founder of algebra. The term algebra itself comes from the title of his book (the word al-jabr meaning "completion" or "rejoining"). His name gave rise to the terms algorism and algorithm, as well as Spanish and Portuguese terms algoritmo, and Spanish guarismo and Portuguese algarismo meaning "digit". In the 12th century, Latin translations of his textbook on arithmetic (Algorithmo de Numero Indorum) which codified the various Indian numerals, introduced the decimal positional number system to the Western world. The Compendious Book on Calculation by Completion and Balancing, translated into Latin by Robert of Chester in 1145, was used until the sixteenth century as the principal mathematical text-book of European universities. In addition to his best-known works, he revised Ptolemy's Geography, listing the longitudes and latitudes of various cities and localities.:9 He further produced a set of astronomical tables and wrote about calendaric works, as well as the astrolabe and the sundial. He also made important contributions to trigonometry, producing accurate sine and cosine tables, and the first table of tangents.

14.5K
10 Oct 2022

Topic Review

Environmental Risk Factors

Environmental health is a growing area of knowledge, continually increasing and updating the body of evidence linking the environment to human health.

14.5K
03 Dec 2022

Topic Review

Religious Cosmology

Religious cosmology is an explanation of the origin, evolution, and eventual fate of the universe, from a religious perspective. This may include beliefs on origin in the form of a creation myth, subsequent evolution, current organizational form and nature, and eventual fate or destiny. There are various traditions in religion or religious mythology asserting how and why everything is the way it is and the significance of it all. Religious cosmologies describe the spatial lay-out of the universe in terms of the world in which people typically dwell as well as other dimensions, such as the seven dimensions of religion; these are ritual, experiential and emotional, narrative and mythical, doctrinal, ethical, social, and material. Religious mythologies may include descriptions of an act or process of creation by a creator deity or a larger pantheon of deities, explanations of the transformation of chaos into order, or the assertion that existence is a matter of endless cyclical transformations. Religious cosmology differs from a strictly scientific cosmology informed by the results of the study of astronomy and similar fields, and may differ in conceptualizations of the world's physical structure and place in the universe, its creation, and forecasts or predictions on its future. The scope of religious cosmology is more inclusive than a strictly scientific cosmology (physical cosmology) in that religious cosmology is not limited to experiential observation, testing of hypotheses, and proposals of theories; for example, religious cosmology may explain why everything is the way it is or seems to be the way it is and prescribing what humans should do in context. Variations in religious cosmology include those such as from India Buddhism, Hindu, and Jain; the religious beliefs of China, Chinese Buddhism, Taoism and Confucianism, Japan's Shintoisim and the beliefs of the Abrahamic faiths, such as Judaism, Christianity, and Islam. Religious cosmologies have often developed into the formal logics of metaphysical systems, such as Platonism, Neoplatonism, Gnosticism, Taoism, Kabbalah, Wuxing or the great chain of being.

14.5K
20 Oct 2022

Topic Review

The drag polar or drag curve is the relationship between the lift on an aircraft and its drag, expressed in terms of the dependence of the drag coefficient on the lift coefficient. It may be described by an equation or displayed in a diagram called a polar plot.

14.5K
24 Oct 2022

Topic Review Video

Fixed and Floating Offshore Structures

Diverse forms of offshore oil and gas structures are utilized for a wide range of purposes and in varying water depths. They are designed for unique environments and water depths around the world. The applications of these offshore structures require different activities for proper equipment selection, design of platform types, and drilling/production methods. There are advances made in ocean engineering which include a variety of innovative offshore structure designs, ranging from fixed platforms to floating platforms. Some of these structures include the deep-water semisubmersible platforms, jack-up rigs, floating offshore wind turbines (FOWTs), FPS (floating production systems) units.

14.5K
19 Aug 2022

Topic Review

Vocaloid is a singing voice synthesizer and the first engine released in the Vocaloid series. It was succeeded by Vocaloid 2. This version was made to be able to sing both English and Japanese.

14.4K
17 Oct 2022

Topic Review

Telegram (Service)

Telegram is a cloud-based instant messaging and voice over IP service developed by Telegram Messenger LLP, a privately held company registered in London, United Kingdom , founded by the Russian entrepreneur Pavel Durov. Telegram client apps are available for Android, iOS, Windows Phone, Windows NT, macOS and Linux. Users can send messages and exchange photos, videos, stickers, audio and files of any type. Telegram's client-side code is open-source software but the source code for recent versions is not always immediately published, whereas its server-side code is closed-source and proprietary. The service also provides APIs to independent developers. In March 2018, Telegram stated that it had 200 million monthly active users. According to its CEO, (As of April 2017), Telegram’s annual growth rate was greater than 50%. Messages and media in Telegram are only client-server encrypted and stored on the servers by default. The service provides end-to-end encryption for voice calls, and optional end-to-end encrypted "secret" chats between two online users, yet not for groups or channels. Telegram's security model has received notable criticism by cryptography experts. They criticized the general security model of permanently storing all contacts, messages and media together with their decryption keys on its servers by default and by not enabling end-to-end encryption for messages by default. Pavel Durov has argued that this is because it helps to avoid third-party unsecure backups, and to allow users to access messages and files from any device. Cryptography experts have furthermore criticized Telegram's use of a custom-designed encryption protocol that has not been proven reliable and secure. Telegram has faced censorship or outright bans in some countries over accusations that the app's services have been used to facilitate illegal activities, such as protests and terrorism, as well as declining demands to facilitate government access to user data and communications.

14.4K
21 Nov 2022

Topic Review

Social Presence Theory

Social presence theory explores how the "sense of being with another" is influenced by digital interfaces in human-computer interactions. Developed from the foundations of interpersonal communication and symbolic interactionism, social presence theory was first formally introduced by John Short, Ederyn Williams, and Bruce Christie in The Social Psychology of Telecommunications. Research on social presence theory has recently developed to examine the efficacy of telecommunications media, including SNS communications. The theory notes that computer-based communication is lower in social presence than face-to-face communication, but different computer-based communications can affect the levels of social presence between communicators and receivers.

14.3K
02 Dec 2022

Topic Review

List of Islands of Australia

This is a list of selected Australian islands grouped by State or Territory. Australia has 8,222 islands within its maritime borders.

14.3K
14 Oct 2022

Topic Review

Marriageable Age

Marriageable age (or marriage age) is the minimum age at which a person is allowed by law to marry, either as a right or subject to parental, judicial or other forms of approval. Age and other prerequisites to marriage vary between jurisdictions, but in the vast majority of jurisdictions, the marriage age as a right is set at the age of majority. Nevertheless, most jurisdictions allow marriage at a younger age with parental or judicial approval, and some also allow younger people to marry if the female is pregnant. Until recently, the marriageable age for girls was lower in many jurisdictions than for boys, on the premise that girls mature at an earlier age than boys. This law has been viewed to be discriminatory, so that in many countries the marriageable age of girls has been raised to equal that of boys. That age is most commonly 18, but there are variations, some higher and some lower. The marriageable age should not be confused with the age of maturity or the age of consent, though, they may be the same in many places. In many developing countries, the official age prescriptions stand as mere guidelines. International organizations, such as UNICEF, regard a marriage by a person below the age of 18 as a child marriage and a violation of human rights. The 55 parties to the 1962 Convention on Consent to Marriage, Minimum Age for Marriage, and Registration of Marriages have agreed to specify a minimum marriage age by statute law‚ to override customary, religious, and tribal laws and traditions. When the marriageable age under a law of a religious community is lower than that under the law of the land, the state law prevails. However, some religious communities do not accept the supremacy of state law in this respect, which may lead to child marriage or forced marriage. The 123 parties to the 1956 Supplementary Convention on the Abolition of Slavery have agreed to adopt a prescribed “suitable” minimum age for marriage.

14.3K
21 Nov 2022

Topic Review

Food Colorants Analysis in Foods

Color additives are used extensively in several food products, as to enhance their appearance, and their nutritional properties. They can be defined as “any substance that its intentional addition of which to a food aiming for a technological (including organoleptic) purpose in the manufacture, processing, preparation treatment, packing, packaging, transport or holding of such food results, or may be reasonably expected to result, in it or its by-products becoming a component of the food or otherwise affecting the characteristics of such foods”. Thus, hereby they are presented all the late advancements related to existing analytical methods and sample preparation methodologies, for their determination and quantification in food matrices.Furthermore, all these advancements are connected to general information about the existing natural or synthetic food colorants, along with legislative information and toxicological aspects, in order to support the importance and the need of appropriate analytical methodologies.

14.3K
12 Jan 2021

Topic Review

The Bible Belt is a region of the Southern United States in which socially conservative Protestant Christianity plays a strong role in society and politics, and church attendance across the denominations is generally higher than the nation's average. The region contrasts with the religiously diverse Midwest and Great Lakes, and the Mormon corridor in Utah and southern Idaho. Whereas the states with the highest percentage of residents identifying as non-religious are in the West and New England regions of the United States (with Vermont at 37%, ranking the highest), in the Bible Belt state of Alabama it is just 12%, and Tennessee has the highest proportion of evangelical Protestants, at 52%. The evangelical influence is strongest in northern Georgia, Tennessee , Alabama, Mississippi, North Carolina, southern and western Virginia, West Virginia, the Upstate region of South Carolina, and East Texas . The earliest known usage of the term "Bible Belt" was by American journalist and social commentator H. L. Mencken, who in 1924 wrote in the Chicago Daily Tribune: "The old game, I suspect, is beginning to play out in the Bible Belt." In 1927, Mencken claimed the term as his invention. The term is now also used in other countries for regions with higher religious doctrine adoption.

14.2K
24 Nov 2022

Topic Review

Examination of Apollo Moon Photographs

The examination of Apollo Moon photographs is an endeavour undertaken by certain people engaged in the debate as to the merits of Moon landing conspiracy theories, despite the abundance of third-party evidence for Apollo Moon landings. A number of allegations and refutations with a variable degree of notability are put forward due to this examination.

14.2K
02 Dec 2022

Topic Review

Renewable Energy Resources in Nigeria

Renewable energy resource utilisation is becoming more prevalent in society and can be a sustainable method to meet rising energy demand and consumption. The International Renewable Energy Agency reports that presently, approximately 33% of total electricity output around the world is from renewable energy sources. In Nigeria, the World Bank reported this figure as 18.2% in 2015. It is important to understand how Nigeria can raise this average as the world moves towards less use of fossil fuels.

14.1K
17 Aug 2022

Topic Review

The Intel 80386, also known as i386 or just 386, is a 32-bit microprocessor introduced in 1985. The first versions had 275,000 transistors and were the CPU of many workstations and high-end personal computers of the time. As the original implementation of the 32-bit extension of the 80286 architecture, the 80386 instruction set, programming model, and binary encodings are still the common denominator for all 32-bit x86 processors, which is termed the i386-architecture, x86, or IA-32, depending on context. The 32-bit 80386 can correctly execute most code intended for the earlier 16-bit processors such as 8086 and 80286 that were ubiquitous in early PCs. (Following the same tradition, modern 64-bit x86 processors are able to run most programs written for older x86 CPUs, all the way back to the original 16-bit 8086 of 1978.) Over the years, successively newer implementations of the same architecture have become several hundreds of times faster than the original 80386 (and thousands of times faster than the 8086). A 33 MHz 80386 was reportedly measured to operate at about 11.4 MIPS. The 80386 was introduced in October 1985, while manufacturing of the chips in significant quantities commenced in June 1986. Mainboards for 80386-based computer systems were cumbersome and expensive at first, but manufacturing was rationalized upon the 80386's mainstream adoption. The first personal computer to make use of the 80386 was designed and manufactured by Compaq and marked the first time a fundamental component in the IBM PC compatible de facto standard was updated by a company other than IBM. In May 2006, Intel announced that 80386 production would stop at the end of September 2007. Although it had long been obsolete as a personal computer CPU, Intel and others had continued making the chip for embedded systems. Such systems using an 80386 or one of many derivatives are common in aerospace technology and electronic musical instruments, among others. Some mobile phones also used (later fully static CMOS variants of) the 80386 processor, such as BlackBerry 950 and Nokia 9000 Communicator. Linux continued to support 80386 processors until December 11, 2012; when the kernel cut 386-specific instructions in version 3.8.

14.1K
23 Oct 2022

Topic Review

Oceanic Climate

An oceanic climate, also known as a marine climate or temperate oceanic climate, is the Köppen classification of climate typical of west coasts in higher middle latitudes of continents, and generally features cool summers (relative to their latitude) and cool but not cold winters, with a relatively narrow annual temperature range and few extremes of temperature. Oceanic climates are defined as having a monthly mean temperature below 22 °C (72 °F) in the warmest month, and above 0 °C (32 °F) (or −3 °C (27 °F) in the coldest month). This climate type is often caused by the onshore flow from the cool, high latitude oceans that are found west of their location. It typically lacks a dry season, as precipitation is more evenly dispersed throughout the year. It is the predominant climate type across much of Western Europe, United Kingdom , New Zealand, the Pacific Northwest region of the United States and Canada, far southwestern South America, a narrow zone of southeastern Australia including Tasmania, and isolated locations elsewhere. Oceanic climates are generally characterised by a narrower annual range of temperatures than in other places at a comparable latitude, and generally do not have the extremely dry summers of Mediterranean climates or the hot and wet summers of humid subtropical climates. Oceanic climates are most dominant in Europe, where they spread much farther inland than in other continents. Oceanic climates can have considerable storm activity as they are located in the belt of the stormy westerlies. Many oceanic climates have frequent cloudy or overcast conditions due to the near constant storms and lows tracking over or near them. The annual range of temperatures is smaller than typical climates at these latitudes due to the constant stable marine air masses that pass through oceanic climates, which lack both very warm and very cool fronts.

14.1K
29 Nov 2022

Topic Review

Agricultural Expansion Drivers and Constraints

Agricultural expansion refers to the conversion of uncultivated land, including natural forests, woodlands, grasslands and wetlands into crop or grazing land, and may be undertaken by smallholders or largescale farmers.

14.1K
30 Apr 2021

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