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Topic Review
Mahindra & Mahindra
Mahindra & Mahindra Limited is an India multinational vehicle Automotive industry corporation headquartered in Mumbai , Maharashtra, India. It was established in 1945 as Muhammad & Mahindra and later renamed as Mahindra and Mahindra. It is one of the largest vehicle manufacturers by production in India and the largest manufacturer of tractors in the world. It is a part of the Mahindra Group, an Indian conglomerate. It was ranked 17th on a list of top companies in India by Fortune India 500 in 2018. Its major competitors in the Indian market include Maruti Suzuki and Tata Motors.
  • 7.0K
  • 23 Nov 2022
Topic Review
Monogamy
Monogamy (/məˈnɒɡəmi/ mə-NOG-ə-mee) is a form of dyadic relationship in which an individual has only one partner during their lifetime—alternately, only one partner at any one time (serial monogamy)—as compared to non-monogamy (e.g., polygamy or polyamory). The term is also applied to the social behavior of some animals, referring to the state of having only one mate at any one time.
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  • 02 Nov 2022
Topic Review
Anki
Anki (/ˈɒŋkiː/; Japanese: [aŋki]) is a free and open-source flashcard program using spaced repetition, a technique from cognitive science for fast and long-lasting memorization. "Anki" (暗記) is the Japanese word for "memorization". The SM-2 algorithm, created for SuperMemo in the late 1980s, forms the basis of the spaced repetition methods employed in the program. Anki's implementation of the algorithm has been modified to allow priorities on cards and to show flashcards in order of their urgency. The cards are presented using HTML and may include text, images, sounds, videos, and LaTeX equations. The decks of cards, along with the user's statistics, are stored in the open SQLite format.
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  • 01 Dec 2022
Topic Review
US Airways Livery
US Airways' aircraft livery has varied both under the US Airways and USAir name. In general the Express and Shuttle divisions have had liveries that closely parallel the company-wide livery at the time. The US Airways livery has been replaced with the new American Airlines livery, in accordance with their merger.
  • 7.0K
  • 16 Nov 2022
Topic Review
AK-630
The AK-630 is a Soviet and Russian fully automatic naval close-in weapon system based on a six-barreled 30 mm rotary cannon. In "630", "6" means 6 barrels and "30" means 30 mm. It is mounted in an enclosed automatic turret and directed by MR-123 radar and television detection and tracking. The system's primary purpose is defense against anti-ship missiles and other precision guided weapons. However it can also be employed against fixed or rotary wing aircraft, ships and other small craft, coastal targets, and floating mines. Once operational, this weapon system was rapidly adopted, with up to 8 units installed in every new Soviet warship (from mine-hunters to aircraft carriers), and hundreds produced in total.
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  • 08 Oct 2022
Topic Review
Bilaminar Blastocyst
Bilaminar blastocyst or bilaminar disc refers to the epiblast and the hypoblast, evolved from the embryoblast. These two layers are sandwiched between two balloons: the primitive yolk sac and the amniotic cavity. The inner cell mass, the embryoblast, begins to transform into two distinct epithelial layers just before implantation occurs. The epiblast is the outer layer that consists of columnar cells. The inner layer is called the hypoblast, or primitive endoderm, which is composed of cuboidal cells. As the two layers become evident, a basement membrane presents itself between the layers. The final two layers of the embryoblast are known collectively as the bilaminar embryonic disc as well as the bilaminar blastocyst or bilaminar blastoderm. This bilaminar blastocyst also defines the primitive dorsal ventral axis. Blastocyst implantation will occur during the second week of fetal development in the endometrium of the uterus; the epiblast is dorsal and the hypoblast is ventral.
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  • 19 May 2023
Topic Review
Elephant
Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are an informal grouping within the proboscidean family Elephantidae. Elephantidae is the only surviving family of proboscideans; extinct members include the mastodons. Elephantidae also contains several extinct groups, including the mammoths and straight-tusked elephants. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears, and convex or level backs. The distinctive features of all elephants include a long proboscis called a trunk, tusks, large ear flaps, massive legs, and tough but sensitive skin. The trunk is used for breathing, bringing food and water to the mouth, and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. The pillar-like legs carry their great weight. Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia and are found in different habitats, including savannahs, forests, deserts, and marshes. They are herbivorous, and they stay near water when it is accessible. They are considered to be keystone species, due to their impact on their environments. Elephants have a fission–fusion society, in which multiple family groups come together to socialise. Females (cows) tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups, which do not include bulls, are usually led by the oldest cow, known as the matriarch. Males (bulls) leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate. They enter a state of increased testosterone and aggression known as musth, which helps them gain dominance over other males as well as reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness, and appear to show empathy for dying and dead family members. African bush elephants and Asian elephants are listed as endangered and African forest elephants as critically endangered by the International Union for Conservation of Nature (IUCN). One of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past, they were used in war; today, they are often controversially put on display in zoos, or exploited for entertainment in circuses. Elephants are highly recognisable and have been featured in art, folklore, religion, literature, and popular culture.
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  • 09 Nov 2022
Topic Review
Philosophy of Max Stirner
The philosophy of Max Stirner is credited as a major influence in the development of individualism, nihilism, existentialism, post-modernism and anarchism (especially of egoist anarchism, individualist anarchism, postanarchism and post-left anarchy). Max Stirner's main philosophical work was The Ego and Its Own, also known as The Ego and His Own (Der Einzige und sein Eigentum in German, or more accurately The Individual and its Property). Stirner's philosophy has been cited as an influence on both his contemporaries, most notably Karl Marx (who was strongly opposed to Stirner's views) as well as subsequent thinkers such as Friedrich Nietzsche, Enrico Arrigoni, Steven T. Byington, Benjamin Tucker, Émile Armand and Albert Camus
  • 7.0K
  • 21 Oct 2022
Topic Review
Urban Legend
An urban legend, urban myth, urban tale, or contemporary legend is a genre of folklore comprising stories circulated as true, especially as having happened to a friend or family member, often with horrifying or humorous elements. These legends can be entertainment, but often concern mysterious peril or troubling events, such as disappearances and strange objects. They may also be confirmation of moral standards, or reflect prejudices, or be a way to make sense of societal anxieties. Urban legends are most often circulated orally, but can be spread by any media, including newspapers, e-mail and social media. Some urban legends have passed through the years with only minor changes to suit regional variations. Recent legends tend to reflect modern circumstances: for instance, the common legend of a person being ambushed and anesthetized, only to wake up and realize that they are now missing a kidney that was supposedly surgically removed for transplantation.
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  • 04 Oct 2022
Topic Review
Construction 4.0
Construction 4.0 is a variety of interdisciplinary technologies, methodologies and concepts that digitize, automate and integrate the construction process at all stages of the value chain
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  • 27 Mar 2023
Topic Review
Transmission Electron Microscopy
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a sensor such as a scintillator attached to a charge-coupled device. Transmission electron microscopes are capable of imaging at a significantly higher resolution than light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands of times smaller than a resolvable object seen in a light microscope. Transmission electron microscopy is a major analytical method in the physical, chemical and biological sciences. TEMs find application in cancer research, virology, and materials science as well as pollution, nanotechnology and semiconductor research, but also in other fields such as paleontology and palynology. TEM instruments have multiple operating modes including conventional imaging, scanning TEM imaging (STEM), diffraction, spectroscopy, and combinations of these. Even within conventional imaging, there are many fundamentally different ways that contrast is produced, called "image contrast mechanisms". Contrast can arise from position-to-position differences in the thickness or density ("mass-thickness contrast"), atomic number ("Z contrast", referring to the common abbreviation Z for atomic number), crystal structure or orientation ("crystallographic contrast" or "diffraction contrast"), the slight quantum-mechanical phase shifts that individual atoms produce in electrons that pass through them ("phase contrast"), the energy lost by electrons on passing through the sample ("spectrum imaging") and more. Each mechanism tells the user a different kind of information, depending not only on the contrast mechanism but on how the microscope is used—the settings of lenses, apertures, and detectors. What this means is that a TEM is capable of returning an extraordinary variety of nanometer- and atomic-resolution information, in ideal cases revealing not only where all the atoms are but what kinds of atoms they are and how they are bonded to each other. For this reason TEM is regarded as an essential tool for nanoscience in both biological and materials fields. The first TEM was demonstrated by Max Knoll and Ernst Ruska in 1931, with this group developing the first TEM with resolution greater than that of light in 1933 and the first commercial TEM in 1939. In 1986, Ruska was awarded the Nobel Prize in physics for the development of transmission electron microscopy.
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  • 05 Dec 2022
Topic Review
Production of Chitosan Nanoparticles
Chitosan Nanoparticles are made from chitosan or its derivatives. The N-deacetylated derivative of chitin is an appealing biopolymer for producing nanoparticles because chitosan has a unique polymeric cationic nature, non-toxicity, high biocompatibility, mucoadhesive properties, absorption-enhancing qualities, and biodegradability.
  • 7.0K
  • 08 Oct 2022
Topic Review
Full-Color Realization of Micro-LED Displays
Emerging technologies, such as smart wearable devices, augmented reality (AR)/virtual reality (VR) displays, and naked-eye 3D projection, have gradually entered our lives, accompanied by an urgent market demand for high-end display technologies. Ultra-high-resolution displays, flexible displays, and transparent displays are all important types of future display technology, and traditional display technology cannot meet the relevant requirements. Micro-light-emitting diodes (micro-LEDs), which have the advantages of a high contrast, a short response time, a wide color gamut, low power consumption, and a long life, are expected to replace traditional liquid-crystal displays (LCD) and organic light-emitting diodes (OLED) screens and become the leaders in the next generation of display technology. However, there are two major obstacles to moving micro-LEDs from the laboratory to the commercial market. One is improving the yield rate and reducing the cost of the mass transfer of micro-LEDs, and the other is realizing a full-color display using micro-LED chips. This study will outline the three main methods for applying current micro-LED full-color displays, red, green, and blue (RGB) three-color micro-LED transfer technology, color conversion technology, and single-chip multi-color growth technology, to summarize present-day micro-LED full-color display technologies and help guide the follow-up research.
  • 7.0K
  • 22 Dec 2020
Topic Review
Nanocarriers
Nanocarriers are added as colloidal nanosystems loaded with therapeutic agents (anticancer agents or any macromolecules, such as proteins or genes), which allow drugs to selectively accumulate at the site of cancerous tumors. As a result of their unique nanometer range, 1–1000 nm (drug administration is preferable in the 5–200 nm range), they are used for cancer treatment. The main and most promising nanocarriers in the literature are iron oxide, gold, polymers, liposomes, micelles, fullerenes (carbon nanotubes, graphene), dendrimers, quantum dots, and nanodiamonds.
  • 7.0K
  • 06 Aug 2021
Topic Review
IBM Mainframe Utility Programs
IBM mainframe utility programs are utility software supplied with IBM mainframe operating systems such as MVS and zOS to carry out various tasks associated with maintenance of the computer system or datasets. The following list describes utilities distributed with OS/360 and successors. No VSE or VM utilities are included.
  • 7.0K
  • 26 Oct 2022
Topic Review
Wife-carrying
Wife carrying (Finnish: eukonkanto or akankanto, Estonian: naisekandmine, Swedish: kärringkånk) is a contest in which male competitors race while each carrying a female teammate. The objective is for the male to carry the female through a special obstacle track in the fastest time. The sport was first introduced at Sonkajärvi, Finland . Several types of carrying may be practised: either a classic piggyback, a fireman's carry (over the shoulder), or Estonian-style (wife upside-down on his back with her legs over the neck and shoulders).
  • 7.0K
  • 11 Oct 2022
Topic Review
The Genetic Basis of Eye Color
Eye color is a polygenic phenotype, and many genetic variants have been highlighted, with the major contributor being the HERC2-OCA2 locus, where many single nucleotide variations (SNPs) were identified.
  • 7.0K
  • 22 Aug 2023
Topic Review
Aesthetics
Aesthetics, or esthetics, is a branch of philosophy that deals with the nature of beauty and taste, as well as the philosophy of art (its own area of philosophy that comes out of aesthetics). It examines aesthetic values, often expressed through judgments of taste. Aesthetics covers both natural and artificial sources of experiences and how we form a judgment about those sources. It considers what happens in our minds when we engage with objects or environments such as viewing visual art, listening to music, reading poetry, experiencing a play, watching a fashion show, movie, sports or even exploring various aspects of nature. The philosophy of art specifically studies how artists imagine, create, and perform works of art, as well as how people use, enjoy, and criticize art. Aesthetics considers why people like some works of art and not others, as well as how art can affect moods or even our beliefs. Both aesthetics and the philosophy of art ask questions like "What is art?," "What is a work of art?," and "What makes good art?" Scholars in the field have defined aesthetics as "critical reflection on art, culture and nature". In modern English, the term "aesthetic" can also refer to a set of principles underlying the works of a particular art movement or theory (one speaks, for example, of a Renaissance aesthetic).
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  • 04 Nov 2022
Topic Review
Aging and Its Molecular Mechanism
Aging is a continuous process over time that is mainly related to natural alterations in mechanical–biological processes. This phenomenon is due to several factors, including the time and energy of biological processes. Aging can be attributed to biological factors such as oxidative stress, cell longevity, and stem cell senescence.
  • 7.0K
  • 22 Apr 2022
Topic Review
Cydonia (Region of Mars)
Cydonia (/sɪˈdoʊniə/, /saɪˈdoʊniə/) is a region on the planet Mars that has attracted both scientific and popular interest. The name originally referred to the albedo feature (distinctively coloured area) that was visible from Earthbound telescopes. The area borders plains of Acidalia Planitia and the Arabia Terra highlands. The area includes the regions: "Cydonia Mensae", an area of flat-topped mesa-like features, "Cydonia Colles", a region of small hills or knobs, and "Cydonia Labyrinthus", a complex of intersecting valleys. As with other albedo features on Mars, the name Cydonia was drawn from classical antiquity, in this case from Kydonia, a historic polis (or "city-state") on the island of Crete. Cydonia contains the "Face on Mars", located about halfway between Arandas Crater and Bamberg Crater.
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  • 25 Oct 2022
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