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Topic Review
Travis (Chimpanzee)
Travis (October 21, 1995 – February 16, 2009) was a male common chimpanzee (Pan troglodytes) who, in February 2009, mauled his owner's friend in Stamford, Connecticut. He blinded her, severed several body parts and lacerated her face. He was shot dead by a police officer. As an animal actor, Travis had appeared in several television shows and commercials, including spots for Pepsi and Old Navy. He had also appeared on The Maury Povich Show, The Man Show, and a television pilot that featured Sheryl Crow and Michael Moore.
  • 6.5K
  • 07 Nov 2022
Topic Review
Transwiki: Multiregional Origin of Modern Humans
The multiregional hypothesis is a scientific model that provides an explanation for the pattern of human evolution. The hypothesis holds that humans first arose near the beginning of the Pleistocene two million years ago and subsequent human evolution has been within a single, continuous human species. This species encompasses archaic human forms such as Homo erectus and Neanderthals as well as modern forms, and evolved worldwide to the diverse populations of modern Homo sapiens sapiens. The theory contends that humans evolve through a combination of adaptation within various regions of the world and gene flow between those regions. Proponents of multiregional origin point to fossil and genomic data and continuity of archaeological cultures as support for their hypothesis. The primary alternative hypothesis is recent African origin of modern humans, which contends that modern humans arose in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace archaic human forms without interbreeding.
  • 6.5K
  • 11 Nov 2022
Biography
Jack Parsons
John Whiteside Parsons (born Marvel Whiteside Parsons;[1] October 2, 1914 – June 17, 1952) was an American rocket engineer, chemist, and Thelemite occultist. Associated with the California Institute of Technology (Caltech), Parsons was one of the principal founders of both the Jet Propulsion Laboratory (JPL) and the Aerojet Engineering Corporation. He invented the first rocket engine to use a
  • 6.5K
  • 15 Nov 2022
Topic Review
Allelopathy
Allelopathy is an ecological phenomenon in which organisms interfere with each other. As a management strategy in agricultural systems, allelopathy can be mainly used to control weeds, resist pests, and disease and improve the interaction of soil nutrition and microorganisms. Volatile organic compounds (VOCs) are allelochemicals volatilized from plants and have been widely demonstrated to have different ecological functions.
  • 6.5K
  • 09 Sep 2021
Topic Review
Space Shuttle Main Engine
The Aerojet Rocketdyne RS-25, otherwise known as the Space Shuttle main engine (SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA's Space Shuttle and is planned to be used on its successor, the Space Launch System. Designed and manufactured in the United States by Rocketdyne (later known as Pratt & Whitney Rocketdyne and Aerojet Rocketdyne), the RS-25 burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing 1,859 kN (418,000 lbf) of thrust at liftoff. Although the RS-25 can trace its heritage back to the 1960s, concerted development of the engine began in the 1970s, with the first flight, STS-1, occurring on April 12, 1981. The RS-25 has undergone several upgrades over its operational history to improve the engine's reliability, safety, and maintenance load. Subsequently, the RS-25D is the most efficient liquid fuel rocket engine currently in use. The engine produces a specific impulse (Isp) of 452 seconds (4.43 km/s) in a vacuum, or 366 seconds (3.59 km/s) at sea level, has a mass of approximately 3.5 tonnes (7,700 pounds), and is capable of throttling between 67% and 109% of its rated power level in one-percent increments. The RS-25 operates at temperatures ranging from −253 °C (−423 °F) to 3300 °C (6000 °F). The Space Shuttle used a cluster of three RS-25 engines mounted in the stern structure of the orbiter, with fuel being drawn from the external tank. The engines were used for propulsion during the entirety of the spacecraft's ascent, with additional thrust being provided by two solid rocket boosters and the orbiter's two AJ-10 orbital maneuvering system engines. Following each flight, the RS-25 engines were removed from the orbiter, inspected, and refurbished before being reused on another mission.
  • 6.5K
  • 24 Oct 2022
Topic Review
Technoversal Leadership
Technoversal Leadership is a theory that goes beyond leader-follower interactions and business concerns such as growth and profit. This style has a discipline to a global understanding of biodiversity loss, climate, and environmental consciousness and the leader rising with them; Technoversal Leadership theory roots where these global crises, technology, and adaptable qualities intersect.
  • 6.5K
  • 29 Jul 2022
Topic Review
Design Considerations of Fixed and Floating Offshore Structures
Offshore structures exist in a variety of forms, and they are used for a variety of functions in varied sea depths. These structures are tailored for certain environments and sea depths and other design considerations. 
  • 6.5K
  • 29 Jul 2022
Topic Review
Hyaluronic Acid
Hyaluronic acid, as a natural linear polysaccharide, has attracted researchers’ attention from its initial detection and isolation from tissues in 1934 until the present day. Due to biocompatibility and a high biodegradation of hyaluronic acid, it finds wide application in bioengineering and biomedicine: from biorevitalizing skin cosmetics and endoprostheses of joint fluid to polymeric scaffolds and wound dressings. However, the main properties of aqueous polysaccharide solutions with different molecular weights are different. Moreover, the therapeutic effect of hyaluronic acid-based preparations directly depends on the molecular weight of the biopolymer. The present entry collects the information about hyaluronic acid and its original properties. Particular emphasis is placed on the structural, physical and physico-chemical properties of hyaluronic acid in water solutions, as well as their degradability.
  • 6.5K
  • 31 Aug 2020
Topic Review
Teeth Blackening
Teeth blackening or teeth lacquering is a custom of dyeing one's teeth black. It was most predominantly practiced in Southeast Asian and Oceanic cultures, particularly among Austronesian, Austroasiatic, and Kra-Dai-speaking peoples. It was also practiced in Japan prior to the Meiji era, as well as in India. It was also performed among some groups in the Americas, most notably among the Shuar people of northern Peru and Ecuador. Teeth blackening is usually done during puberty. It was primarily done to preserve the teeth into old age, as it prevents tooth decay similar to the mechanism of modern dental sealants. It was seen as a sign of maturity, beauty, and civilization. A common belief is that blackened teeth differentiated humans from animals. Teeth blackening is often done in conjunction with traditions of tooth sharpening and evulsion, as well as other body modification customs like tattoos. Teeth blackening and filing were regarded with fascination and disapproval by early European explorers and colonists. The practice survives in some isolated ethnic groups in Southeast Asia and Oceania but has mostly disappeared after the introduction of Western beauty standards during the colonial era, and continues among many minority groups in China, Pacific Islands and Southeast Asia. It is mainly prevalent in older women, though the practice is still carried on by some younger women. Sometimes artificial teeth are used to achieve blackened teeth. Teeth blackening is commonly confused with the red-stained teeth from betel chewing. However, betel chewing damages the teeth and gums, while teeth blackening does not.
  • 6.5K
  • 21 Nov 2022
Topic Review
Wind Tower Houses in Dubai
Due to the similar climate conditions and proximity of the United Arab Emirates to other neighboring countries such as Iran and India, who have been familiar with the use of wind towers as cooling devices for a long time, wind towers were readily adopted in traditional buildings in the UAE. The most concentrated number of wind towers can be found in the residential neighborhood of Dubai called Alfahidi Historic Area. The number reaches around 50 wind towers in less than 0.25 km2, with an average of one wind tower per house. This neighborhood was originally designed for merchants who immigrated from Bastak in Iran. Later, wind towers were applied to various different types of buildings, such as shops and stores, as well as other residential neighborhoods of Shindagah and Deira.
  • 6.5K
  • 19 Apr 2022
Topic Review
Responsive Architecture
Responsive architecture is a type of architecture, an artificial entity, that reacts to data and information collected by a variety of types of sensors. It is also defined as an interactive and collective platform where diverse computing or operating systems are executed, leading to architectural behaviors like changing forms or services.
  • 6.5K
  • 20 May 2021
Topic Review
Micronutrient Deficiency and Toxicity in Plants
Micronutrients are essential for plants. Their growth, productivity and reproduction are directly influenced by the supply of micronutrients. Currently, there are eight trace elements considered to be essential for higher plants: Fe, Zn, Mn, Cu, Ni, B, Mo, and Cl. Possibly, other essential elements could be discovered because of recent advances in nutrient solution culture techniques and in the commercial availability of highly sensitive analytical instrumentation for elemental analysis.
  • 6.5K
  • 27 Sep 2022
Topic Review
Melatonin Protects Mitochondria and Adenosine Triphosphate Production
Melatonin (N-acetyl-5-methoxytryptamine) is a ubiquitous, mitochondria-targeted molecule present in all tested eukarya and bacteria. In March 2022, the first discovery of the serotonin N-acetyltransferase (SNAT) gene—responsible for the penultimate formation of N-acetylserotonin (NAS) before its final conversion into melatonin — in archaea further consolidates the status of melatonin as a regulator of biomolecular condensates in all three domains of life in the cellular empire. RNA viruses including SARS-CoV-2 contain proteins with intrinsically disordered regions that undergo liquid-liquid phase separation (LLPS). Liquid-liquid phase separation (LLPS) of these proteins form membraneless condensates that act as “viral factories” to facilitate and enhance replication. Phase separation of the SARS-CoV-2 nucleocapsid (N) protein is associated with mitochondrial dysfunction and rewiring of energy production away from oxidative phosphorylation (OXPHOS) to favor aerobic glycolysis in cytoplasm. Increased adenosine triphosphate (ATP) in cytoplasm supports viral replication. Melatonin protects mitochondria from damage, maintains adequate levels to disassemble “viral factories”, and prevents suppression of host antiviral immune responses by inhibiting nucleocapsid phase separation via antioxidant-dependent and -independent means.
  • 6.5K
  • 05 Sep 2022
Topic Review
Home Economics
Home economics, or family and consumer sciences, is a subject concerning human development, personal and family finances, consumer issues, housing and interior design, nutrition and food preparation, as well as textiles and apparel. Home economics courses are offered around the world and across multiple educational levels. Internationally, it is coordinated by the International Federation for Home Economics. Historically, the purpose of these courses was to professionalize housework, to provide intellectual fulfillment for women, and to emphasize the value of "women's work" in society and to prepare them for the traditional roles of sexes. However, it has since evolved into family and consumer sciences to cover additional subject matter outside of just home life and wellness. Family and consumer sciences are taught as an elective or required course in secondary education, as a continuing education course in institutions, and at the primary level.   Beginning as home economics in the United States, the course was a key part of the education system for teaching one the art of taking care of a household. In the 19th and early 20th century, it was a woman-dominated course, teaching women to be homemakers and efficient household managers. The American Association of Family and Consumer Sciences was created as an answer to more Americans desiring youth to learn vocational skills. Politics played a role in home economics education, and it wasn’t until later in the century that the course shifted from being woman-dominated to now required for both sexes.   Now family and consumer science have been included in the broader subject of Career Technical Education, a program that teaches skilled trades, applied sciences, modern technologies, and career preparation. Despite the subjects over the past century, there has been a major decline in home economics courses offered by educational institutions.  
  • 6.5K
  • 09 Nov 2022
Topic Review
Libra
The constellation Libra, known as the Scales or the Balance, is one of the 12 zodiac constellations representing an inanimate object. It is located in the southern sky and is associated with justice and balance. Libra is depicted as scales held by the Greek goddess of justice, Astraea, and is the only zodiac constellation named after an object rather than an animal or character from mythology.
  • 6.5K
  • 15 Mar 2024
Topic Review
Human Sex Ratio
In anthropology and demography, the human sex ratio is the ratio of males to females in a population. More data are available for humans than for any other species, and the human sex ratio is more studied than that of any other species, but interpreting these statistics can be difficult. Like most sexual species, the sex ratio in humans is close to 1:1. In humans, the natural ratio between males and females at birth is slightly biased towards the male sex, being estimated to be about 1.05 or 1.06 or within a narrow range from 1.03 to 1.06 males/per female born. Sex imbalance may arise as a consequence of various factors including natural factors, exposure to pesticides and environmental contaminants, war casualties, sex-selective abortions, infanticides, aging, gendercide and problems with birth registration. The sex ratio for the entire world population is 100 males to 100 females (2021 est.). Human sex ratios, either at birth or in the population as a whole, are reported in any of four ways: the ratio of males to females, the ratio of females to males, the proportion of males, or the proportion of females. If there are 108,000 males and 100,000 females the ratio of males to females is 1.080 and the proportion of males is 51.9%. Scientific literature often uses the proportion of males. This article uses the ratio of males to females, unless specified otherwise.
  • 6.5K
  • 08 Oct 2022
Topic Review
Machine Learning Techniques in Cybersecurity
Machine learning is of rising importance in cybersecurity. The primary objective of applying machine learning in cybersecurity is to make the process of malware detection more actionable, scalable and effective than traditional approaches, which require human intervention. The cybersecurity domain involves machine learning challenges that require efficient methodical and theoretical handling. Several machine learning and statistical methods, such as deep learning, support vector machines and Bayesian classification, among others, have proven effective in mitigating cyber-attacks. The detection of hidden trends and insights from network data and building of a corresponding data-driven machine learning model to prevent these attacks is vital to design intelligent security systems.
  • 6.5K
  • 01 Aug 2022
Topic Review
Metal Oxide Applications
Metal oxides play a key role in environmental remediation.
  • 6.5K
  • 08 Dec 2020
Topic Review
Bio-Composites
Bio-composites are degradable, renewable, non-abrasive, and non-toxic, with comparable properties to those of synthetic fiber composites and used in many applications in various fields. Naturals fibers are abundant and have low harvesting costs with adequate mechanical properties. Hazards of synthetic fibers, recycling issues, and toxic byproducts are the main driving factors in the research and development of bio-composites. Bio-composites are fabricated by combining natural fibers in a matrix material. The matrix material can be biodegradable, non-biodegradable, or synthetic. Synthetic matrix materials, along with natural fibers, are used to form hybrid bio-composites.
  • 6.5K
  • 09 Mar 2021
Topic Review
Prajñā (Hinduism)
Pragña or Pragya (Sanskrit: प्रज्ञ) as प्रज्ञा, प्राज्ञ and प्राज्ञा is used to refer to the highest and purest form of wisdom, intelligence and understanding. Pragya is the state of wisdom which is higher than the knowledge obtained by reasoning and inference.
  • 6.5K
  • 25 Oct 2022
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