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Topic Review
Ballad
A ballad is a form of verse, often a narrative set to music. Ballads derive from the medieval French chanson balladée or ballade, which were originally "dance songs". Ballads were particularly characteristic of the popular poetry and song of Britain and Ireland from the later medieval period until the 19th century. They were widely used across Europe, and later in Australia, North Africa, North America and South America. Ballads are often 13 lines with an ABABBCBC form, consisting of couplets (two lines) of rhymed verse, each of 14 syllables. Another common form is ABAB or ABCB repeated, in alternating 8 and 6 syllable lines. Many ballads were written and sold as single sheet broadsides. The form was often used by poets and composers from the 18th century onwards to produce lyrical ballads. In the later 19th century, the term took on the meaning of a slow form of popular love song and is often used for any love song, particularly the sentimental ballad of pop or rock music, although the term is also associated with the concept of a stylized storytelling song or poem, particularly when used as a title for other media such as a film.
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  • 04 Nov 2022
Topic Review
Xiaomi Redmi Note 4
The Xiaomi Redmi Note 4 is the fourth smartphone of Redmi Note series developed by Xiaomi Inc. It is a part of Xiaomi's budget Redmi smartphone line. It has two variants: The older version sold as Redmi Note 4 is powered by a Deca-core Mediatek MT6797 Helio X20 SOC. The upgraded version, sold both as Redmi Note 4X and Redmi Note 4 (where MTK version was not released) is powered by an Octa-core MSM8953 Qualcomm Snapdragon 625 SoC. The Redmi Note 4 was succeeded by Redmi Note 5.
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  • 26 Oct 2022
Topic Review
High Frequency Active Auroral Research Program
The High Frequency Active Auroral Research Program (HAARP) was initiated as an ionospheric research program jointly funded by the United States Air Force , the U.S. Navy, the University of Alaska Fairbanks, and the Defense Advanced Research Projects Agency (DARPA). It was designed and built by BAE Advanced Technologies (BAEAT). Its original purpose was to analyze the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance. As a university-owned facility, HAARP is a high-power, high-frequency transmitter used for study of the ionosphere. The most prominent instrument at HAARP is the Ionospheric Research Instrument (IRI), a high-power radio frequency transmitter facility operating in the high frequency (HF) band. The IRI is used to temporarily excite a limited area of the ionosphere. Other instruments, such as a VHF and a UHF radar, a fluxgate magnetometer, a digisonde (an ionospheric sounding device), and an induction magnetometer, are used to study the physical processes that occur in the excited region. Work on the HAARP facility began in 1993. The current working IRI was completed in 2007; its prime contractor was BAE Systems Advanced Technologies. As of 2008, HAARP had incurred around $250 million in tax-funded construction and operating costs. In May 2014, it was announced that the HAARP program would be permanently shut down later in the year. After discussions between the parties, ownership of the facility and its equipment was transferred to the University of Alaska Fairbanks in August 2015. HAARP is a target of conspiracy theorists, who claim that it is capable of "weaponizing" weather. Commentators and scientists say that advocates of this theory are uninformed, as claims made fall well outside the abilities of the facility, if not the scope of natural science.
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  • 21 Nov 2022
Topic Review
Aparigraha
In Hinduism and Jainism, aparigraha (Sanskrit: अपरिग्रह) is the virtue of non-possessiveness, non-grasping or non-greediness. Aparigrah is the opposite of parigrah, and refers to keeping the desire for possessions to what is necessary or important, depending on one's life stage and context. The precept of aparigraha is a self-restraint (temperance) from the type of greed and avarice where one's own material gain or happiness comes by hurting, killing or destroying other human beings, life forms or nature. Aparigraha is related to and in part a motivator of dāna (proper charity), both from giver's and receiver's perspective.
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  • 13 Oct 2022
Topic Review
Pathogenic Bacteria
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. By contrast, several thousand species are part of the gut flora present in the digestive tract. The body is continually exposed to many species of bacteria, including beneficial commensals, which grow on the skin and mucous membranes, and saprophytes, which grow mainly in the soil and in decaying matter. The blood and tissue fluids contain nutrients sufficient to sustain the growth of many bacteria. The body has defence mechanisms that enable it to resist microbial invasion of its tissues and give it a natural immunity or innate resistance against many microorganisms. Pathogenic bacteria are specially adapted and endowed with mechanisms for overcoming the normal body defences, and can invade parts of the body, such as the blood, where bacteria are not normally found. Some pathogens invade only the surface epithelium, skin or mucous membrane, but many travel more deeply, spreading through the tissues and disseminating by the lymphatic and blood streams. In some rare cases a pathogenic microbe can infect an entirely healthy person, but infection usually occurs only if the body's defence mechanisms are damaged by some local trauma or an underlying debilitating disease, such as wounding, intoxication, chilling, fatigue, and malnutrition. In many cases, it is important to differentiate infection and colonization, which is when the bacteria are causing little or no harm. Caused by Mycobacterium tuberculosis bacteria, one of the diseases with the highest disease burden is tuberculosis, which killed 1.4 million people in 2019, mostly in sub-Saharan Africa. Pathogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus, Pneumococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter, and Salmonella. Pathogenic bacteria also cause infections such as tetanus, typhoid fever, diphtheria, syphilis, and leprosy. Pathogenic bacteria are also the cause of high infant mortality rates in developing countries. Most pathogenic bacteria can be grown in cultures and identified by Gram stain and other methods. Bacteria grown in this way are often tested to find which antibiotics will be an effective treatment for the infection. For hitherto unknown pathogens, Koch's postulates are the standard to establish a causative relationship between a microbe and a disease.
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  • 07 Nov 2022
Topic Review
Embryology of Aorta
The aorta is the largest elastic artery in the human body and is classically divided into two anatomical segments, the thoracic and the abdominal aorta, separated by the diaphragm. The thoracic aorta includes the aortic root, the ascending aorta, the arch, and the descending aorta. The aorta’s elastic properties depend on its wall structure, composed of three distinct histologic layers: intima, media, and adventitia. The different aortic segments show different embryological and anatomical features, which account for their different physiological properties and impact the occurrence and natural history of congenital and acquired diseases that develop herein.
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  • 30 Jun 2023
Topic Review
Five Precepts
The five precepts (Pali: pañcasīla; Sanskrit: pañcaśīla) or five rules of training (Pali: pañcasikkhapada; Sanskrit: pañcaśikṣapada) is the most important system of morality for Buddhist lay people. They constitute the basic code of ethics undertaken by lay followers of Buddhism. The precepts are commitments to abstain from killing living beings, stealing, sexual misconduct, lying and intoxication. Within the Buddhist doctrine, they are meant to develop mind and character to make progress on the path to enlightenment. They are sometimes referred to as the śrāvakayāna precepts in the Mahāyāna tradition, contrasting them with the bodhisattva precepts. The five precepts form the basis of several parts of Buddhist doctrine, both lay and monastic. With regard to their fundamental role in Buddhist ethics, they have been compared with the ten commandments in Christianity or the ethical codes of Confucianism. The precepts have been connected with utilitarianist, deontological and virtue approaches to ethics. They have been compared with human rights because of their universal nature, and some scholars argue they can complement the concept of human rights. The five precepts were common to the religious milieu of 6th-century BCE India, but the Buddha's focus on awareness through the fifth precept was unique. As shown in Early Buddhist Texts, the precepts grew to be more important, and finally became a condition for membership of the Buddhist religion. When Buddhism spread to different places and people, the role of the precepts began to vary. In countries where Buddhism had to compete with other religions, such as China, the ritual of undertaking the five precepts developed into an initiation ceremony to become a Buddhist lay person. On the other hand, in countries with little competition from other religions, such as Thailand, the ceremony has had little relation to the rite of becoming Buddhist, as many people are presumed Buddhist from birth. Undertaking and upholding the five precepts is based on the principle of non-harming (Pāli and Sanskrit: ahiṃsa). The Pali Canon recommends one to compare oneself with others, and on the basis of that, not to hurt others. Compassion and a belief in karmic retribution form the foundation of the precepts. Undertaking the five precepts is part of regular lay devotional practice, both at home and at the local temple. However, the extent to which people keep them differs per region and time. People keep them with an intention to develop themselves, but also out of fear of a bad rebirth. The first precept consists of a prohibition of killing, both humans and all animals. Scholars have interpreted Buddhist texts about the precepts as an opposition to and prohibition of capital punishment, suicide, abortion and euthanasia. In practice, however, many Buddhist countries still use the death penalty. With regard to abortion, Buddhist countries take the middle ground, by condemning though not prohibiting it. The Buddhist attitude to violence is generally interpreted as opposing all warfare, but some scholars have raised exceptions. The second precept prohibits theft. The third precept refers to adultery in all its forms, and has been defined by modern teachers with terms such as sexual responsibility and long-term commitment. The fourth precept involves falsehood spoken or committed to by action, as well as malicious speech, harsh speech and gossip. The fifth precept prohibits intoxication through alcohol, drugs or other means. Early Buddhist Texts nearly always condemn alcohol, and so do Chinese Buddhist post-canonical texts. Buddhist attitudes toward smoking differ per time and region, but are generally permissive. In modern times, traditional Buddhist countries have seen revival movements to promote the five precepts. As for the West, the precepts play a major role in Buddhist organizations. They have also been integrated in mindfulness training programs, though many mindfulness specialists do not support this because of the precepts' religious import. Lastly, many conflict prevention programs make use of the precepts.
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  • 22 Nov 2022
Topic Review
STEAMComp Edu: STEAM Competence Framework for Educators
STEAM (science, technology, engineering, arts, and mathematics) education is gaining increasing attention worldwide, with many initiatives being implemented to promote its adoption and effectiveness; thus, its successful integration into educational systems has become increasingly critical. Educators will play a central role in this integration; that is why it is critical to assess their needs, map the necessary roles and competences, and provide the means to guide their professional development in a systematic way. To address these requirements, our study introduces the STEAM Competence Framework for Educators (STEAMComp Edu), as a culmination of literature reviews, expert consultations, and empirical validation by 302 educational professionals, policymakers, and scholars.
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  • 09 Nov 2024
Topic Review
List of Human Spaceflight Programs
This is a list of human spaceflight programs, including successful programs, programs that were canceled, and programs planned for the future. The criteria for what constitutes human spaceflight vary. The FAI defines spaceflight as any flight over 100 kilometers (62 mi). In the U.S. professional, military, and commercial astronauts who travel above an altitude of 80 kilometers (50 mi) are awarded astronaut wings. This article follows the FAI definition of spaceflight. Until the 21st century, human spaceflight programs were sponsored exclusively by governments, through either the military or civilian space agencies. With the launch of the privately funded SpaceShipOne in 2004, a new category of human spaceflight programs – commercial human spaceflight – arrived.
  • 7.6K
  • 09 Nov 2022
Topic Review
Smart manufacturing, an advanced form of traditional manufacturing
Traditional manufacturing is an industrial process that converts materials into a finished product using a labor-intensive low-end operation, low precision, average resource utilization and efficiency for economic value.
  • 7.6K
  • 28 Mar 2022
Topic Review
Wife
A wife is a female partner in a continuing marital relationship. The term continues to be applied to a woman who has separated from her partner, and ceases to be applied to such a woman only when her marriage has come to an end, following a legally recognized divorce or the death of her spouse. On the death of her partner, a wife is referred to as a widow, but not after she is divorced from her partner. The rights and obligations of a wife in relation to her partner and her status in the community and in law vary between cultures and have varied over time.
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  • 17 Nov 2022
Topic Review
Rice Husk
The development of engineered silica particles by using low-cost renewable or waste resources is a key example of sustainability. Rice husks have emerged as a renewable resource for the production of engineered silica particles as well as bioenergy.
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  • 17 Jan 2022
Topic Review
Artemisia vulgaris L. (common mugwort)
Artemisia vulgaris L. (common mugwort) is a species with great importance in the history of medicine and was called the “mother of herbs” in the Middle Ages. It is a common herbaceous plant that exhibits high morphological and phytochemical variability depending on the location it occurs. This species is well known almost all over the world. Its herb—Artemisiae vulgaris herba—is used as a raw material due to the presence of volatile oil, flavonoids, and sesquiterpene lactones and their associated biological activities. The European Pharmacopoeia has listed this species as a potential homeopathic raw material. Moreover, this species has been used in traditional Chinese, Hindu, and European medicine to regulate the functioning of the gastrointestinal system and treat various gynecological diseases. The general aim of this review was to analyze the progress of phytochemical and pharmacological as well as professional scientific studies focusing on A. vulgaris. Thus far, numerous authors have confirmed the beneficial properties of A. vulgaris herb extracts, including their antioxidant, hepatoprotective, antispasmolytic, antinociceptive, estrogenic, cytotoxic, antibacterial, and antifungal effects. In addition, several works have reviewed the use of this species in the production of cosmetics and its role as a valuable spice in the food industry. 
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  • 05 Nov 2020
Topic Review
ISO Standards for Trailer Connectors
A number of ISO standards cover trailer connectors, the electrical connectors between vehicles and the trailers they tow that provide a means of control for the trailers. These are listed below, with notes on significant deviations from them that can cause problems.
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  • 07 Nov 2022
Topic Review
Accretion (Astrophysics)
In astrophysics, accretion is the accumulation of particles into a massive object by gravitationally attracting more matter, typically gaseous matter, in an accretion disk. Most astronomical objects, such as galaxies, stars, and planets, are formed by accretion processes.
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  • 11 Nov 2022
Topic Review
Post-WWII Anti-fascism
Antifa movements (/ænˈtiːfə, ˈæntiˌfɑː/) and Anti-Fascist Action networks are left wing, often anarchist, extra-parliamentary and often violent political movements that describe themselves as anti-fascist. Such movements have been active in several countries in the second half of the 20th and early 21st century.
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  • 09 Nov 2022
Topic Review
Deformation (Engineering)
In engineering, deformation refers to the change in size or shape of an object. Displacements are the absolute change in position of a point on the object. Deflection is the relative change in external displacements on an object. Strain is the relative internal change in shape of an infinitesimally small cube of material and can be expressed as a non-dimensional change in length or angle of distortion of the cube. Strains are related to the forces acting on the cube, which are known as stress, by a stress-strain curve. The relationship between stress and strain is generally linear and reversible up until the yield point and the deformation is elastic. The linear relationship for a material is known as Young's modulus. Above the yield point, some degree of permanent distortion remains after unloading and is termed plastic deformation. The determination of the stress and strain throughout a solid object is given by the field of strength of materials and for a structure by structural analysis. Engineering stress and engineering strain are approximations to the internal state that may be determined from the external forces and deformations of an object, provided that there is no significant change in size. When there is a significant change in size, the true stress and true strain can be derived from the instantaneous size of the object. In the figure it can be seen that the compressive loading (indicated by the arrow) has caused deformation in the cylinder so that the original shape (dashed lines) has changed (deformed) into one with bulging sides. The sides bulge because the material, although strong enough to not crack or otherwise fail, is not strong enough to support the load without change. As a result, the material is forced out laterally. Internal forces (in this case at right angles to the deformation) resist the applied load. The concept of a rigid body can be applied if the deformation is negligible.
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  • 24 Oct 2022
Topic Review
Zip (File Format)
ZIP files generally use the file extensions .zip or .ZIP and the MIME media type application/zip. ZIP is used as a base file format by many programs, usually under a different name. When navigating a file system via a user interface, graphical icons representing ZIP files often appear as a document or other object prominently featuring a zipper.
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  • 14 Oct 2022
Topic Review
History of Nanotechnology
The history of nanotechnology traces the development of the concepts and experimental work falling under the broad category of nanotechnology. Although nanotechnology is a relatively recent development in scientific research, the development of its central concepts happened over a longer period of time. The emergence of nanotechnology in the 1980s was caused by the convergence of experimental advances such as the invention of the scanning tunneling microscope in 1981 and the discovery of fullerenes in 1985, with the elucidation and popularization of a conceptual framework for the goals of nanotechnology beginning with the 1986 publication of the book Engines of Creation. The field was subject to growing public awareness and controversy in the early 2000s, with prominent debates about both its potential implications as well as the feasibility of the applications envisioned by advocates of molecular nanotechnology, and with governments moving to promote and fund research into nanotechnology. The early 2000s also saw the beginnings of commercial applications of nanotechnology, although these were limited to bulk applications of nanomaterials rather than the transformative applications envisioned by the field.
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  • 17 Oct 2022
Topic Review
Agriculture in Ancient Mesopotamia
Agriculture was the main economic activity in ancient Mesopotamia. Operating under harsh constraints, notably the arid climate, the Mesopotamian farmers developed effective strategies that enabled them to support the development of the first states, the first cities, and then the first known empires, under the supervision of the institutions which dominated the economy: the royal and provincial palaces, the temples, and the domains of the elites. They focused above all on the cultivation of cereals (particularly barley) and sheep farming, but also farmed legumes, as well as date palms in the south and grapes in the north. In reality, there were two types of Mesopotamian agriculture, corresponding to the two main ecological domains, which largely overlapped with cultural distinctions. The agriculture of southern or Lower Mesopotamia, the land of Sumer and Akkad, which later became Babylonia received almost no rain and required large scale irrigation works which were supervised by temple estates, but could produce high returns. The agriculture of Northern or Upper Mesopotamia, the land that would eventually become Assyria, had enough rainfall to allow dry agriculture most of the time so that irrigation and large institutional estates were less important, but the returns were also usually lower.
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  • 02 Dec 2022
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