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Topic Review
Mathematical Modeling and Computational Tools in Drug Design
The conventional drug discovery approach is an expensive and time-consuming process, but its limitations have been overcome with the help of mathematical modeling and computational drug design approaches. Previously, finding a small molecular candidate as a drug against a disease was very costly and required a long time to screen a compound against a specific target. The development of novel targets and small molecular candidates against different diseases including emerging and reemerging diseases remains a major concern and necessitates the development of novel therapeutic targets as well as drug candidates as early as possible. In this regard, computational and mathematical modeling approaches for drug development are advantageous due to their fastest predictive ability and cost-effectiveness features. Computer-aided drug design (CADD) techniques utilize different computer programs as well as mathematics formulas to comprehend the interaction of a target and drugs. Traditional methods to determine small-molecule candidates as a drug have several limitations, but CADD utilizes novel methods that require little time and accurately predict a compound against a specific disease with minimal cost.
  • 4.4K
  • 01 Aug 2022
Topic Review
Ray-Finned Fish
Actinopterygii (/ˌæktɪnɒptəˈrɪdʒiaɪ/; from actino- 'having rays', and grc πτέρυξ (ptérux) 'wing, fins'), members of which are known as ray-finned fishes, is a clade (traditionally class or subclass) of the bony fishes. They comprise over 50% of living vertebrate species. The ray-finned fishes are so-called because their fins are webs of skin supported by bony or horny spines (rays), as opposed to the fleshy, lobed fins that characterize the class Sarcopterygii (lobe-finned fish). These actinopterygian fin rays attach directly to the proximal or basal skeletal elements, the radials, which represent the link or connection between these fins and the internal skeleton (e.g., pelvic and pectoral girdles). By species count, actinopterygians dominate the vertebrates, and they comprise nearly 99% of the over 30,000 species of fish. They are ubiquitous throughout freshwater and marine environments from the deep sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 mm (0.3 in), to the massive ocean sunfish, at 2,300 kg (5,070 lb), and the long-bodied oarfish, at 11 m (36 ft). The vast majority of Actinopterygii (~99%) are teleosts.
  • 4.4K
  • 29 Nov 2022
Topic Review
Light-independent Reactions
The light-independent reactions, or dark reactions, of photosynthesis are chemical reactions that convert carbon dioxide and other compounds into glucose. These reactions occur in the stroma, the fluid-filled area of a chloroplast outside the thylakoid membranes. These reactions take the products (ATP and NADPH) of light-dependent reactions and perform further chemical processes on them.
  • 4.2K
  • 09 Nov 2022
Topic Review
Short-Faced Bear
The short-faced bear (Arctodus sp.) is an extinct bear genus that inhabited North America during the Pleistocene epoch from about 1.8 Mya until 11,000 years ago. It was the most common tremarctine bear in North America and many of its fossils have been found in the La Brea tar pits in southern California . There are two recognized species: the lesser short-faced bear (Arctodus pristinus) and the giant short-faced bear (Arctodus simus), with the latter considered to be one of the largest known terrestrial mammalian carnivores that has ever existed. It has been hypothesized that their extinction coincides with the Younger Dryas period of global cooling commencing around 10,900 BC.
  • 4.2K
  • 05 Nov 2022
Topic Review
Dracorex
Dracorex is a controversial dinosaur genus of the family Pachycephalosauridae, from the Late Cretaceous of North America. The type (and only known) species is Dracorex hogwartsia, meaning "dragon king of Hogwarts". This dinosaur is named for the wizard school in Harry Potter books. It is known from one nearly complete skull (the holotype TCMI 2004.17.1), as well as four cervical vertebrae: the atlas, third, eighth and ninth. These were discovered in the Hell Creek Formation in South Dakota by three amateur paleontologists from Sioux City, in the U.S. state of Iowa. The skull was subsequently donated to the Children's Museum of Indianapolis for study in 2004, and was formally described by Bob Bakker and Robert Sullivan in 2006. However, Jack Horner et al. suspect that it is a juvenile Pachycephalosaurus and an analysis of pachycephalosaur fossils by a joint team from the University of California, Berkeley and the Museum of the Rockies has questioned the validity of two named genera of pachycephalosaur, Dracorex and Stygimoloch. According to the team, specimens of Dracorex and Stygimoloch might actually represent earlier growth stages of Pachycephalosaurus. This has been supported in a 2016 analysis of the youngest Pachycephalosaurus material known, which indicates that the unique features of Dracorex represent instead ontogenetically variant features on a Pachycephalosaurus growth curve.
  • 4.1K
  • 03 Nov 2022
Biography
Guru Nanak
Gurū Nānak (15 April 1469 – 22 September 1539), also referred to as Bābā Nānak ('father Nānak'),[1] was the founder of Sikhism and is the first of the ten Sikh Gurus. His birth is celebrated worldwide as Guru Nanak Gurpurab on Katak Pooranmashi ('full-moon of Kattak'), i.e. October–November. Nanak is said to have travelled far and wide across Asia teaching people the message of ik onk
  • 4.1K
  • 09 Dec 2022
Topic Review
Arthropod
Arthropods (/ˈɑːrθrəpɒd/, from grc ἄρθρον (arthron) 'joint', and πούς (pous) 'foot' (gen. ποδός)) are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong. Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, but many species give birth to live young after the eggs have hatched inside the mother, and a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. The evolutionary ancestry of arthropods dates back to the Cambrian period. The group is generally regarded as monophyletic, and many analyses support the placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall, however, the basal relationships of animals are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated. Today, Arthropods contribute to the human food supply both directly as food, and more importantly, indirectly as pollinators of crops. Some species are known to spread severe disease to humans, livestock, and crops.
  • 4.1K
  • 06 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.
  • 4.0K
  • 09 Nov 2022
Topic Review
Evolution of Dinosaurs
Dinosaurs evolved within a single lineage of archosaurs 243-233 Ma (million years ago) from the Anisian to the Carnian ages, the latter part of the middle Triassic. Dinosauria is a well-supported clade, present in 98% of bootstraps. It is diagnosed by many features including loss of the postfrontal on the skull and an elongate deltopectoral crest on the humerus. In March 2017, scientists reported a new way of classifying the dinosaur family tree, based on newer and more evidence than available earlier. According to the new classification, the original dinosaurs, arising 200 million years ago, were small, two-footed omnivorous animals with large grasping hands. Descendants (for the non-avian dinosaurs) lasted until 66 million years ago.
  • 4.0K
  • 14 Oct 2022
Topic Review
Flocculus (Cerebellar)
The flocculus (Latin: tuft of wool, diminutive) is a small lobe of the cerebellum at the posterior border of the middle cerebellar peduncle anterior to the biventer lobule. Like other parts of the cerebellum, the flocculus is involved in motor control. It is an essential part of the vestibulo-ocular reflex, and aids in the learning of basic motor skills in the brain. It is associated with the nodulus of the vermis; together, these two structures compose the vestibular part of the cerebellum. At its base, the flocculus receives input from the inner ear's vestibular system and regulates balance. Many floccular projections connect to the motor nuclei involved in control of eye movement.
  • 4.0K
  • 02 Nov 2022
Biography
Masaru Emoto
Masaru Emoto (江本 勝, Emoto Masaru, July 22, 1943 – October 17, 2014)[1] was a Japanese businessman, author and pseudoscientist who claimed that human consciousness could affect the molecular structure of water. His 2004 book The Hidden Messages in Water was a New York Times best seller.[2] His conjecture evolved over the years, and his early work revolved around pseudoscientific hypothese
  • 4.0K
  • 30 Nov 2022
Topic Review
African Golden Wolf
The African golden wolf (Canis lupaster) or African wolf is a canine native to North Africa, West Africa, the Sahel, northern East Africa, and the Horn of Africa. It is the descendant of a genetically admixed canid of 72% gray wolf (Canis lupus) and 28% Ethiopian wolf (Canis simensis) ancestry. It is listed as least concern on the IUCN Red List. In the Atlas Mountains, it was sighted in elevations as high as 1,800 m (5,900 ft). It is primarily a predator, targeting invertebrates and mammals as large as gazelle fawns, though larger animals are sometimes taken. Its diet also includes animal carcasses, human refuse, and fruit. The African golden wolf is a monogamous and territorial species; offspring remain with the family to assist in raising their parents' younger pups. It was previously classified as an African variant of the golden jackal (Canis aureus), with at that time at least one subspecies (C. a. lupaster) having been classified as a wolf. In 2015, a series of analyses on the species' mitochondrial DNA and nuclear genome demonstrated that it was, in fact, distinct from the golden jackal, and more closely related to the gray wolf and the coyote (Canis latrans). It is nonetheless still close enough to the golden jackal to produce hybrid offspring, as indicated through genetic tests on jackals in Israel, and a 19th-century captive crossbreeding experiment. It plays a prominent role in some African cultures; in North African folklore, it is viewed as an untrustworthy animal whose body parts can be used for medicinal or ritualistic purposes, while it is held in high esteem in Senegal's Serer religion as being the first creature to be created by the god Roog.
  • 4.0K
  • 23 Nov 2022
Topic Review
Forgetting
Forgetting or disremembering is the apparent loss or modification of information already encoded and stored in an individual's short or long-term memory. It is a spontaneous or gradual process in which old memories are unable to be recalled from memory storage. Problems with remembering, learning and retaining new information are a few of the most common complaints of older adults. Studies show that retention improves with increased rehearsal. This improvement occurs because rehearsal helps to transfer information into long-term memory. Forgetting curves (amount remembered as a function of time since an event was first experienced) have been extensively analyzed. The most recent evidence suggests that a power function provides the closest mathematical fit to the forgetting function.
  • 4.0K
  • 09 Oct 2022
Biography
Mohamed Al-Fayed
Mohamed Al-Fayed (/ælfaɪˈɛd/; Egyptian Arabic: محمد أنور شاكر عبد السيد الفايد‎ [mahamad el fajed]; born 27 January 1929) is an Egyptian business magnate. Fayed's business interests include ownership of Hôtel Ritz Paris and formerly Harrods Department Store, Knightsbridge. Al-Fayed sold his ownership of Fulham F.C. to Shahid Khan in 2013.[1] In his personal life
  • 4.0K
  • 05 Dec 2022
Topic Review
Grinder (Biohacking)
Grinders are people who apply the hacker ethic to improve their own bodies with do it yourself cybernetic devices or introducing Biochemicals into the body to enhance or change their bodies' functionality. Many grinders identify with the biopunk movement, open-source transhumanism, and techno-progressivism. The Grinder movement is strongly associated with the body modification movement and practices actual implantation of cybernetic devices in organic bodies as a method of working towards transhumanism, such as designing and installing do-it-yourself body-enhancements such as magnetic implants. Biohacking emerged in a growing trend of non-institutional science and technology development. According to Biohack.me, "Grinders are passionate individuals who believe the tools and knowledge of science belong to everyone. Grinders practice functional extreme body modification in an effort to improve the human condition. [Grinders] hack [them]selves with electronic hardware to extend and improve human capacities. Grinders believe in action, [thei]r bodies the experiment." "Biohacking" can also refer to managing one's own biology using a combination of medical, nutritional and electronic techniques. This may include the use of nootropics, non-toxic substances, and/or cybernetic devices for recording biometric data (as in the Quantified Self movement).
  • 4.0K
  • 21 Nov 2022
Biography
Bill Maher
William Maher (/mɑːr/; born January 20, 1956)[1] is an American comedian, political commentator, and television host. He is known for the HBO political talk show Real Time with Bill Maher (2003–present) and the similar late-night show called Politically Incorrect (1993–2002), originally on Comedy Central and later on ABC. Maher is known for his political satire[2] and sociopolitical comme
  • 3.9K
  • 29 Nov 2022
Biography
John Fleming
John Irving Fleming is an Australian priest and bioethicist. He was the founding president of Campion College.[1] Fleming was originally an Anglican priest but later became a Roman Catholic priest. He is currently suspended from public ministry. The son of an Anglican priest, Fleming graduated with a B.A. from the University of Adelaide, a Licentiate in Theology from the Australian College of
  • 3.9K
  • 26 Dec 2022
Biography
Stephen Hawking
Stephen William Hawking CH CBE FRS FRSA (8 January 1942 – 14 March 2018) was an English theoretical physicist, cosmologist, and author who was director of research at the Centre for Theoretical Cosmology at the University of Cambridge at the time of his death.[1][2][3] He was the Lucasian Professor of Mathematics at the University of Cambridge between 1979 and 2009. Hawking was born in Oxford
  • 3.9K
  • 30 Nov 2022
Biography
Hindemburg Melão Jr.
Hindemburg Melão Jr. (born 15 January 1972, in São Paulo) is a Brazilian philosopher, investor, epistemologist, theologian, author, retired chess player, amateur astrophotographer, and science popularizer.[1] Hindemburg has written over 1600 articles on science, philosophy, chess, finance, among other fields, and the book IMC na Balança ("BMI on the scale"). Hindemburg is known as a player o
  • 3.9K
  • 12 Dec 2022
Topic Review
Sea Urchin
Sea urchins (/ˈɜːrtʃɪnz/) are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone — from the intertidal seashore down to 5,000 metres (16,000 ft; 2,700 fathoms). The spherical, hard shells (tests) of sea urchins are round and spiny, ranging in diameter from 3 to 10 cm (1 to 4 in). Sea urchins move slowly, crawling with tube feet, and also propel themselves with their spines. Although algae are the primary diet, sea urchins also eat slow-moving (sessile) animals. In the food chain, the predators who eat sea urchins are the sea otter and the starfish, the wolf eel, the triggerfish, and human beings. Adult sea urchins have fivefold symmetry, but their pluteus larvae feature bilateral (mirror) symmetry, indicating that the sea urchin belongs to the Bilateria group of animal phyla, which also comprises the chordates and the arthropods, the annelids and the molluscs, and are found in every ocean and in every climate, from the tropics to the polar regions, and inhabit marine benthic (sea bed) habitats, from rocky shores to hadal zone depths. The fossil record of the Echinoids dates from the Ordovician period, some 450 million years ago; the closest echinoderm relatives of the sea urchin are the sea cucumbers (Holothuroidea); both are deuterostomes, a clade that includes the chordates. The animals have been studied since the 19th century as model organisms in developmental biology, as their embryos were easy to observe; this has continued with studies of their genomes because of their unusual fivefold symmetry and relationship to chordates. Species such as the slate pencil urchin are popular in aquariums, where they are useful for controlling algae. Fossil urchins have been used as protective amulets.
  • 3.9K
  • 19 Oct 2022
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