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Topic Review
Gotra
In Hindu society, the term gotra (Sanskrit: गोत्र) is commonly considered to be equivalent to clan. It broadly refers to people who are descendants in an unbroken male line from a common male ancestor or patriline. Generally the gotra forms an exogamous unit, with the marriage within the same gotra being prohibited by custom, being regarded as incest. The name of the gotra can be used as a surname, but it is different from a surname and is strictly maintained because of its importance in marriages among Hindus, especially among the higher castes. Pāṇini defines gotra for grammatical purposes as apatyam pautraprabhrti gotram (IV. 1. 162), which means "the word gotra denotes the progeny (of a sage) beginning with the son's son." When a person says "I am Vipparla-gotra", he means that he traces his descent from the ancient sage Vipparla by unbroken male descent. According to the Brihadaranyaka Upanisad 2.2.6, Gautama and Bharadvāja, Viśvāmitra and Jamadagni, Vashishtha and Kaśhyapa and Shandilya are seven sages (also known as saptarishi); the progeny of these seven sages are declared to be gotras. This enumeration of seven primary gotras seems to have been known to Pāṇini. The offspring (apatya) of these seven are gotras and others than these are called gotrâvayava. One who follows the system defined by three sages defines himself as tri-a-rishaye. Similarly, for five sages, it is pancha-rishaye, and for seven sages, it is sapta-rishaye. There exists another theory about gotra: sons and disciples of a sage would have the same gotra; it is believed that they possess similar thought and philosophy. People of the same gotra can be found across different castes. Each Gotra comprises pravaras.
  • 20.9K
  • 30 Nov 2022
Topic Review
Fuel Economy in Aircraft
The fuel economy in aircraft is the measure of the transport energy efficiency of aircraft. Efficiency is increased with better aerodynamics and by reducing weight, and with improved engine BSFC and propulsive efficiency or TSFC. Endurance and range can be maximized with the optimum airspeed, and economy is better at optimum altitudes, usually higher. An airline efficiency depends on its fleet fuel burn, seating density, air cargo and passenger load factor, while operational procedures like maintenance and routing can save fuel. Average fuel burn of new aircraft fell 45% from 1968 to 2014, a compounded annual reduction 1.3% with a variable reduction rate. In 2018, CO₂ emissions totalled 747 million tonnes for passenger transport, for 8.5 trillion revenue passenger kilometres (RPK), giving an average of 88 gram CO₂ per RPK. A 88 gCO₂/km represents 28 g of fuel per km, or a 3.5 L/100 km (67 mpg‑US) fuel consumption. New technology can reduce engine fuel consumption, like higher pressure and bypass ratios, geared turbofans, open rotors, hybrid electric or fully electric propulsion; and airframe efficiency with retrofits, better materials and systems and advanced aerodynamics.
  • 20.9K
  • 01 Nov 2022
Topic Review
Creatine Monohydrate
Creatine (N-(aminoiminomethyl)-N-methyl glycine) is a naturally occurring nitrogen-containing compound that plays an integral role in cellular metabolism. Creatine monohydrate (CrM) supplementation increases muscle phosphagen levels, improves repetitive high-intensity exercise performance, and promotes greater training adaptations. No significant side effects other than weight gain have been reported from CrM supplementation despite widespread use throughout the world. 
  • 20.8K
  • 07 Mar 2022
Topic Review
Physico-Chemical Properties of Sodium Alginate
The macromolecules of natural origin have attracted the attention of many researchers as essential to protect the structures of unstable drug substances. After analyzing the studies carried out by various authors, researchers found that these molecules are used for both investigational and therapeutic purposes. This requires the design of certain drug delivery formulations knowing the nature of the macromolecule, its target organ, the required dose and the route of delivery. Therefore, researchers consider it important to use sodium alginate to optimize the delivery of drug substances for maximum therapeutic performance in the body after administration.
  • 20.8K
  • 19 Oct 2022
Topic Review
Wiktionary
Wiktionary is a multilingual, web-based project to create a free content dictionary of all words in all languages. It is collaboratively edited via a wiki, and its name is a portmanteau of the words wiki and dictionary. It is available in 171 languages and in Simple English. Like its sister project Wikipedia, Wiktionary is run by the Wikimedia Foundation, and is written collaboratively by volunteers, dubbed "Wiktionarians". Its wiki software, MediaWiki, allows almost anyone with access to the website to create and edit entries. Because Wiktionary is not limited by print space considerations, most of Wiktionary's language editions provide definitions and translations of words from many languages, and some editions offer additional information typically found in thesauri and lexicons. The English Wiktionary includes a thesaurus (formerly known as Wikisaurus) of synonyms of various words. Wiktionary data are frequently used in various natural language processing tasks.
  • 20.7K
  • 08 Nov 2022
Topic Review
Lalitaditya Muktapida of Kashmir
Lalitaditya Muktapida of Kashmir, an eminent 8th-century ruler, is a significant yet often overlooked figure in Indian history. Known for his unparalleled military prowess, Lalitaditya never lost a battle, whether against the Arabs or his contemporaries. Beyond his martial achievements, he was a prolific builder, responsible for the construction of numerous cities and monumental structures, including the grand Martand Sun Temple and his capital, Parihaspura. His reign in Kashmir was characterised by wide territorial control and cultural flowering.
  • 20.7K
  • 02 Jul 2024
Topic Review
Black Cumin and Kidney Injury
The prevalence of chronic kidney disease (CKD) is increasing worldwide, and a close association between acute kidney injury (AKI) and CKD has recently been identified. Black cumin (Nigella sativa) has been shown to be effective in treating various kidney diseases. Accumulating evidence shows that black cumin and its vital compound, thymoquinone (TQ), can protect against kidney injury caused by various xenobiotics, namely chemotherapeutic agents, heavy metals, pesticides, and other environmental chemicals. Black cumin can also protect the kidneys from ischemic shock. The mechanisms underlying the kidney protective potential of black cumin and TQ include antioxidation, anti-inflammation, anti-apoptosis, and antifibrosis which are manifested in their regulatory role in the antioxidant defense system, NF-κB signaling, caspase pathways, and TGF-β signaling. 
  • 20.6K
  • 01 Sep 2021
Topic Review
Process of Converting Ammonia to Hydrogen
Hydrogen technology for transition to a hydrogen-based economy requires supplying clean and renewable energy and capture of CO2 from current fossil hydrogen production. Ammonia is the most popular substance as a green hydrogen carrier because it does not carry carbon, and the total hydrogen content of ammonia is higher than other fuels and is thus suitable to convert to hydrogen. Ammonia cracking is a process of producing hydrogen from ammonia decomposition over a catalyst at high temperatures and is preferentially performed at normal pressures. 
  • 20.6K
  • 12 Dec 2022
Topic Review
Government Censorship of Telegram Messenger
Telegram Messenger application has been blocked by multiple countries.
  • 20.6K
  • 14 Nov 2022
Topic Review
Physical Law
A physical law or a law of physics is a statement "inferred from particular facts, applicable to a defined group or class of phenomena, and expressible by the statement that a particular phenomenon always occurs if certain conditions be present." Physical laws are typically conclusions based on repeated scientific experiments and observations over many years and which have become accepted universally within the scientific community. The production of a summary description of our environment in the form of such laws is a fundamental aim of science. These terms are not used the same way by all authors. The distinction between natural law in the political-legal sense and law of nature or physical law in the scientific sense is a modern one, both concepts being equally derived from physis, the Greek word (translated into Latin as natura) for nature.
  • 20.5K
  • 01 Dec 2022
Topic Review
Folk Dance
A folk dance is a dance developed by people that reflect the life of the people of a certain country or region. Not all ethnic dances are folk dances. For example, ritual dances or dances of ritual origin are not considered to be folk dances. Ritual dances are usually called "Religious dances" because of their purpose. The terms "ethnic" and "traditional" are used when it is required to emphasize the cultural roots of the dance. In this sense, nearly all folk dances are ethnic ones. If some dances, such as polka, cross ethnic boundaries and even cross the boundary between "folk" and "ballroom dance", ethnic differences are often considerable enough to mention.
  • 20.4K
  • 12 Oct 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.
  • 20.4K
  • 01 Nov 2022
Topic Review
Thelema
Thelema (/θəˈliːmə/) is a social or spiritual philosophy derived from Western esotericism. The word thelema is the English transliteration of the Koine Greek noun θέλημα (pronounced [θélɛ:ma]), "will", from the verb θέλω (ethélō): "to will, wish, want or purpose". While Thelema is most often regarded as a religion it is also often called a philosophy. Thelema was developed in the early 1900s by Aleister Crowley, an English writer, mystic, and ceremonial magician. He believed himself to be the prophet of a new age, the Æon of Horus, based upon a spiritual experience that he and his wife, Rose Edith, had in Egypt in 1904. By his account, a possibly non-corporeal or "praeterhuman" being that called itself Aiwass contacted him through Rose and dictated, through Rose, a text known as The Book of the Law or Liber AL vel Legis, which outlined the principles of Thelema. The Thelemic pantheon—a collection of gods and goddesses who either literally exist or serve as symbolic archetypes or metaphors, depending on one's viewpoint—includes a number of deities, primarily a trio adapted from ancient Egyptian religion, who are the three speakers of The Book of the Law: Nuit, Hadit and Ra-Hoor-Khuit. Crowley described these deities as a "literary convenience". The religion is founded on the idea that the 20th century marked the beginning of the Aeon of Horus, in which a new ethical code would be followed: "Do what thou wilt shall be the whole of the Law". This means that adherents of Thelema should seek out and follow their true path, i.e. their True Will. The philosophy also emphasizes the ritual practice of Magick. As Crowley developed the religion, he wrote widely on the topic, as well as producing more "inspired" writings that he collectively termed The Holy Books of Thelema. He also associated Thelemic spiritual practice with concepts rooted in occultism, yoga, and Eastern and Western mysticism, especially the Qabalah. Aspects of Thelema and Crowley's thought in general inspired the development of Wicca and, to a certain degree, the rise of Modern Paganism as a whole, as well as chaos magick and Satanism. Some scholars, such as Hugh Urban, also believe Thelema to have been an influence on the development of Scientology, but others, such as J. Gordon Melton, deny any such connection.
  • 20.4K
  • 20 Oct 2022
Topic Review
Erikson's Stages of Psychosocial Development
Erikson's stages of psychosocial development, as articulated in the second half of the 20th century by Erik Erikson in collaboration with Joan Erikson, is a comprehensive psychoanalytic theory that identifies a series of eight stages that a healthy developing individual should pass through from infancy to late adulthood. According to Erikson’s theory the results from each stage, whether positive or negative, influences the results of succeeding stages. Erikson published a book called Childhood and Society around the 1950s that made his research well known on the eight stages of psychosocial development. Erikson was originally influenced by Sigmund Freud’s psychosexual stages of development. He began by working with Freud's theories specifically, but as he began to dive deeper into biopsychosocial development and how other environmental factors affect human development, he soon progressed past Freud’s theories and developed his own ideas. Erikson's stage theory characterizes an individual advancing through the eight life stages as a function of negotiating their biological and sociocultural forces. The two conflicting forces each have a psychosocial crisis which characterizes the eight stages. If an individual does indeed successfully reconcile these forces (favoring the first mentioned attribute in the crisis), they emerge from the stage with the corresponding virtue. For example, if an infant enters into the toddler stage (autonomy vs. shame and doubt) with more trust than mistrust, they carry the virtue of hope into the remaining life stages. The challenges of stages not successfully completed may be expected to return as problems in the future. However, mastery of a stage is not required to advance to the next stage. In one study, subjects showed significant development as a result of organized activities.
  • 20.4K
  • 20 Oct 2022
Topic Review
Cretaceous–Paleogene Extinction Event
The Cretaceous–Paleogene (K–Pg) extinction event, also known as the Cretaceous–Tertiary (K–T) extinction,[lower-alpha 2] was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. With the exception of some ectothermic species such as the sea turtles and crocodilians, no tetrapods weighing more than 25 kilograms (55 pounds) survived. It marked the end of the Cretaceous period, and with it the end of the entire Mesozoic Era, opening the Cenozoic Era that continues today. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the K–Pg boundary, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows high levels of the metal iridium, which is rare in the Earth's crust, but abundant in asteroids. As originally proposed in 1980 by a team of scientists led by Luis Alvarez and his son Walter, it is now generally thought that the K–Pg extinction was caused by the impact of a massive comet or asteroid 10 to 15 km (6 to 9 mi) wide, 66 million years ago, which devastated the global environment, mainly through a lingering impact winter which halted photosynthesis in plants and plankton. The impact hypothesis, also known as the Alvarez hypothesis, was bolstered by the discovery of the 180 km (112 mi) Chicxulub crater in the Gulf of Mexico's Yucatán Peninsula in the early 1990s, which provided conclusive evidence that the K–Pg boundary clay represented debris from an asteroid impact. The fact that the extinctions occurred simultaneously provides strong evidence that they were caused by the asteroid. A 2016 drilling project into the Chicxulub peak ring confirmed that the peak ring comprised granite ejected within minutes from deep in the earth, but contained hardly any gypsum, the usual sulfate-containing sea floor rock in the region: The gypsum would have vaporized and dispersed as an aerosol into the atmosphere, causing longer-term effects on the climate and food chain. In October 2019, researchers reported that the event rapidly acidified the oceans producing ecological collapse and, in this way as well, produced long-lasting effects on the climate, and accordingly was a key reason for the end-Cretaceous mass extinction. In January 2020, scientists reported new evidence that the extinction event was mostly a result of the meteorite impact and not volcanism. Other causal or contributing factors to the extinction may have been the Deccan Traps and other volcanic eruptions, climate change, and sea level change. A wide range of species perished in the K–Pg extinction, the best-known being the non-avian dinosaurs. It also destroyed a myriad of other terrestrial organisms, including some mammals, pterosaurs, birds, lizards, insects, and plants. In the oceans, the K–Pg extinction killed off plesiosaurs and mosasaurs and devastated teleost fish, sharks, mollusks (especially ammonites, which became extinct), and many species of plankton. It is estimated that 75% or more of all species on Earth vanished. Yet the extinction also provided evolutionary opportunities: In its wake, many groups underwent remarkable adaptive radiation — sudden and prolific divergence into new forms and species within the disrupted and emptied ecological niches. Mammals in particular diversified in the Paleogene, evolving new forms such as horses, whales, bats, and primates. The surviving group of dinosaurs were avians, ground and water fowl who radiated into all modern species of bird. Teleost fish, and perhaps lizards also radiated.
  • 20.4K
  • 03 Nov 2022
Topic Review
Investment in Tourism Infrastructure Development
Investment in tourism infrastructure includes investment in components such as transport and communications infrastructure, the hotel and restaurant industry, and recreation facilities... Investment in tourism infrastructure development to make destinations and services increasingly attractive is considered a key measure in developing a country’s tourist destinations. It has a strong and positive impact on visitor attraction. 
  • 20.3K
  • 18 Sep 2021
Topic Review
Nutritional Value of Fish
Fish are considered highly nutritious products of the aquaculture system due to the presence of well-balanced macronutrients such as proteins, lipids and micronutrients such as vitamins and minerals
  • 20.2K
  • 28 Nov 2022
Topic Review
Unified Atomic Mass Unit
The unified atomic mass unit or dalton (symbol: u, or Da) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass). One unified atomic mass unit is approximately the mass of one nucleon (either a single proton or neutron) and is numerically equivalent to 1 g/mol. It is defined as one twelfth of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest, and has a value of 1.660539040(20)×10−27 kg, or approximately 1.66 yoctograms. The CIPM has categorised it as a non-SI unit accepted for use with the SI, and whose value in SI units must be obtained experimentally. The amu without the "unified" prefix is technically an obsolete unit based on oxygen, which was replaced in 1961. However, many sources still use the term amu but now define it in the same way as u (i.e., based on carbon-12). In this sense, most uses of the terms atomic mass units and amu, today, actually refer to unified atomic mass unit. For standardization, a specific atomic nucleus (carbon-12 vs. oxygen-16) had to be chosen because the average mass of a nucleon depends on the count of the nucleons in the atomic nucleus due to mass defect. This is also why the mass of a proton or neutron by itself is more than (and not equal to) 1 u. The atomic mass unit is not the unit of mass in the atomic units system, which is rather the electron rest mass (me).
  • 20.2K
  • 21 Oct 2022
Topic Review
2004 Indian Ocean Tsunami in Malaysia
The tsunami is one of the deadliest natural disasters, responsible for more than 260,000 deaths and billions in economic losses over the last two decades. The footage of the devastating power of the 2004 Indian Ocean tsunami perhaps remains vivid in the memory of most survivors, and Malaysia was one of the countries affected by the unprecedented 2004 tsunami. It was the first time the Malaysian government had managed such a great disaster. A compilation of post-event observations regarding tsunami characteristics is first presented in the form of maps, followed by building damage, including damage modes of wall failure, total collapse, debris impact and tilting of structures.
  • 20.2K
  • 17 Jun 2025
Topic Review
Digitalisation of organisations and COVID-19
The COVID-19 pandemic caused profound shifts in the functioning of organisations, with the increased mobilisation of the implementation of digitalisation processes in the activities of the members of these coordinated collective units. In this perspective, based on our academic experience and recent literature, this paper offers some dimensions that seem to us relevant to ponder with special urgency, and that will shape both organisations in the near future and an organisational culture that is, in many cases, renewed.
  • 20.2K
  • 28 Oct 2020
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