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Topic Review
Huītzilōpōchtli
In Aztec mythology, Huitzilopochtli (Template:Lang-nci-IPA, modern Nahuatl pronunciation (help·info)) is the deity of war, sun, human sacrifice, and the patron of the city of Tenochtitlan. He was also the tribal god of the Mexicas, also known as the Aztecs, of Tenochtitlan. Many in the pantheon of deities of the Aztecs were inclined to have a fondness for a particular aspect of warfare. However, Huitzilopochtli was known as the primary god of war in ancient Mexico. Since he was the patron god of the Mexica, he was credited with both the victories and defeats that the Mexica people had on the battlefield. The people had to make sacrifices to him to protect the Aztec from infinite night. He wielded Xiuhcoatl, the fire serpent, as a weapon, thus also associating Huitzilopochtli with fire. As noted by the Spaniards during their discovery and conquest of the Aztec Empire (wherein they recorded the deity's name as Huichilobos), human sacrifice was common in worship ceremonies, which took place frequently and in numerous temples throughout the region, and when performed they typically sacrificed multiple victims per day at a given temple.
  • 6.5K
  • 15 Nov 2022
Topic Review
Hot Dry Rock Geothermal Energy
Hot dry rock (HDR) is an extremely abundant source of geothermal energy that is difficult to access. A vast store of thermal energy is contained within hot – but essentially dry and impervious crystalline basement rocks found almost everywhere deep beneath Earth's surface. A concept for the extraction of useful amounts of geothermal energy from HDR originated at the Los Alamos National Laboratory in 1970, and Laboratory researchers were awarded a U.S. patent covering it. This technology has been tested extensively with multiple deep wells drilled in several field areas around world including the USA, Japan, Australia, France, and the UK and investment of billions of research funds. It continues to be the focus along with a related technique called EGS for sizable government-led research studies involving costly deep drilling and rock studies. Thermal energy has been recovered in reasonably sustainable tests over periods of years and in some cases electrical power generation was also achieved. However no commercial projects are ongoing or likely due to the high cost and limited capacity of the engineered reservoirs, associated wells, and pumping systems. Commonly tests have opened just one or more fractures such that the reservoir surface heat exchange areas are limited. For this technology to successfully compete with other energy sources, drilling costs would have to drop drastically or new approaches that result in much more extensive, complex, and higher rate flow paths through actual fracture networks would have to be established. The enthusiasim evident here on Wikipedia and in the research community is justified by the vast extent of the energy supply and the low environmental impact of the method however significant breakthroughs will be required to make this a commercial energy resource.
  • 6.5K
  • 30 Oct 2022
Topic Review
Big Data Mining
Big data mining (BDM) is an approach that uses the cumulative data mining or extraction techniques on large datasets / volumes of data. It is mainly focused on retrieving relevant and demanded information (or patterns) and thus extracting value hidden in data of an immense volume. BDM draws from the conventional data mining notation but also combines the aspects of big data, i.e. it enables to acquire useful information from databases or data streams that are huge in terms of “big data V’s”, like volume, velocity, and variety.
  • 6.4K
  • 05 Aug 2021
Topic Review
Natural Herbals and Spices in Wound Healing
Herbal medicines have been employed in folk medicine to accelerate wound healing since ancient times. Many plants and various preparations thereof have been used traditionally in relation to wound treatment, especially due to their immense potential to affect wound healing. Plant-based extracts and/or isolates support tissue regeneration through a variety of mechanisms, which often work together to improve the whole healing process. Currently, the efficacy of many of these herbs is well documented together with their mechanisms of action. Therefore, natural products as well as their pure compounds are an emerging source of alternative medicinal compounds for the management of various diseases, among which is wound healing.
  • 6.4K
  • 29 Jun 2022
Topic Review
Iron-Containing Oral Contraceptives
Oral contraceptive use has been associated with decreased menstrual blood losses; thus, can independently reduce the risk of anemia and iron deficiency in women. Manufacturers have recently started to include supplemental iron in the non-hormonal placebo tablets of some contraceptives. 
  • 6.4K
  • 15 Jul 2021
Topic Review
Perovskite Materials
In the development of hydrogen-based technology, a key challenge is the sustainable production of hydrogen in terms of energy consumption and environmental aspects. However, existing methods mainly rely on fossil fuels due to their cost efficiency, and as such, it is difficult to be completely independent of carbon-based technology. Electrochemical hydrogen production is essential, since it has shown the successful generation of hydrogen gas of high purity. Similarly, the photoelectrochemical (PEC) method is also appealing, as this method exhibits highly active and stable water splitting with the help of solar energy. We discuss the exceptional optical and electrical characteristics of perovskite materials which often dictate PEC performance. We further extend our discussion to the material limit of perovskite under a hydrogen production environment, i.e., that PEC reactions often degrade the contact between the electrode and the electrolyte.
  • 6.4K
  • 30 Jul 2021
Topic Review
Elephantinae
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.
  • 6.4K
  • 10 Oct 2022
Topic Review
Muhajir (Pakistani)
The Muhajir (Urdu: مہاجر‎, also spelled Mahajir and Mohajir) are Muslim immigrants, of multi-ethnic origin, and their descendants, who migrated from various regions of India after the Partition of India to settle in the newly independent state of Pakistan . The term Muhajirs refers to those Muslim migrants from India who mostly settled in urban Sindh.
  • 6.4K
  • 23 Jan 2024
Topic Review
African Sheep Breeds
The African continent is home to more than 400 million heads of sheep, the majority of which are classified as indigenous and raised primarily for subsistence. They live and thrive well in a wide range of climatic and production conditions, ranging from unfavorable to favorable environments. 
  • 6.4K
  • 17 Sep 2021
Topic Review
Affect and Personality in Fibromyalgia
Fibromyalgia syndrome (FMS) is a chronic disorder characterized by widespread and persistent musculoskeletal pain, which is usually associated with other symptoms such as fatigue, tiredness, insomnia, stiffness, cognitive deficits, and emotional comorbidities (i.e., depression and anxiety). FMS patients usually display a high rate of psychiatric disorders compared to the general population. FMS has been also associated with higher levels of negative affect and lower levels of positive affect. High levels of stress, pain catastrophizing, and angry rumination have been also reported in FMS patients. Additionally, there are a tendency to internalize and suppress anger in FMS patients. Regarding personality in FMS, some studies have observed some FMS features (e.g., high impulsivity, harm avoidance, self-transcendence and neuroticism, and low conscientiousness, cooperativeness and self-directedness), while other authors had not found any particular personality trait. Some personality disorders (i.e., obsessive-compulsive personality disorder, borderline personality, avoidant personality disorder, and histrionic personality disorder) seem to be more frequent in FMS patients than in general population. Moreover, previous research has reported a greater presence of the type D personality and high levels of alexithymia in a significant proportion of FMS patients. It is necessary to improve the understanding of the role of affect and personality in the clinical practice with chronic pain patients, in order to improve the success of a personalized oriented treatment and increase their health-related quality of life.
  • 6.4K
  • 27 Oct 2020
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