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Biography
Harvey Fletcher
Harvey Fletcher (September 11, 1884 – July 23, 1981) was an American physicist.[1] Known as the "father of stereophonic sound," he is credited with the invention of the 2-A audiometer[2] and an early electronic hearing aid.[3][4] He was an investigator into the nature of speech and hearing, and made contributions in acoustics, electrical engineering, speech, medicine, music, atomic physics, so
  • 2.3K
  • 25 Nov 2022
Topic Review
Phrynosoma
Horned lizards (Phrynosoma), also known as horny toads or horntoads, are a genus of North American lizards and the type genus of the family Phrynosomatidae. The common names refer directly to their horns or to their flattened, rounded bodies, and blunt snouts. The generic name Phrynosoma means "toad-bodied". In common with true toads (amphibians of the family Bufonidae), horned lizards tend to move sluggishly, often remain motionless, and rely on their remarkable camouflage to avoid detection by predators. They are adapted to arid or semiarid areas. The spines on the lizard's back and sides are modified reptile scales, which prevent water loss through the skin, whereas the horns on the head are true horns (i.e., they have a bony core). Of the 22 species of horned lizards, 15 are native to the United States. The largest-bodied and most widely distributed of the US species is the Texas horned lizard.
  • 2.3K
  • 26 Oct 2022
Topic Review
Social Sequence Analysis
Social sequence analysis is a special application of sequence analysis, a set of methods that were originally designed in bioinformatics to analyze DNA, RNA, and peptide sequences. Social sequence analysis involves the examination of ordered social processes, ranging from microsocial interaction patterns (for example, turn-taking dynamics in conversations) and interpersonal contact dynamics to the development of social hierarchies and macrosocial temporal patterns. The analysis of such patterns can involve descriptive accounts of sequence patterns, statistical event history analysis, optimal matching analysis, narrative or event structure analysis, and dynamic social network sequencing. After being introduced to the social sciences in the 1980s and a period of slow growth during the 1990s, social sequence methods have become increasingly prevalent.
  • 2.3K
  • 01 Nov 2022
Biography
Ching W. Tang
Ching W. Tang (Chinese: 鄧青雲; pinyin: Dèng Qīngyún) is a Hong Kong-born American physical chemist. He was born in Yuen Long, Hong Kong in 1947. Tang currently is the Doris Johns Cherry Professor in the Chemical Engineering Department, University of Rochester.[1] He also has joint appointments in the Department of Chemistry and the Department of Physics and Astronomy. Tang has joined HKUS
  • 2.3K
  • 15 Nov 2022
Topic Review
Semantic Memory
Semantic memory refers to general world knowledge that we have accumulated throughout our lives. This general knowledge (facts, ideas, meaning and concepts) is intertwined in experience and dependent on culture. Semantic memory is distinct from episodic memory, which is our memory of experiences and specific events that occur during our lives, from which we can recreate at any given point. For instance, semantic memory might contain information about what a cat is, whereas episodic memory might contain a specific memory of petting a particular cat. We can learn about new concepts by applying our knowledge learned from things in the past. Semantic memory and episodic memory are both types of explicit memory (or declarative memory), that is, memory of facts or events that can be consciously recalled and "declared". The counterpart to declarative or explicit memory is nondeclarative memory or implicit memory.
  • 2.3K
  • 22 Nov 2022
Topic Review
Bell's Mania
Bell's mania, also known as delirious mania, refers to an acute neurobehavioral syndrome. This is usually characterized by an expeditious onset of delirium, mania, psychosis, followed by grandiosity, emotional lability, altered consciousness, hyperthermia, and in extreme cases, death. It is sometimes misdiagnosed as excited delirium (EXD) or catatonia due to the presence of overlapping symptoms. Pathophysiology studies reveal elevated dopamine levels in the neural circuit as the underlying mechanism. Psychostimulant users as well as individuals experiencing severe manic episodes are more prone to the manifestation of this condition. Management solutions such as sedation and ketamine injections have been discussed for medical professionals and individuals with the condition. Bell's mania cases are commonly reported in countries like the United States and Canada and are commonly associated with psychostimulant use and abuse.
  • 2.3K
  • 08 Nov 2022
Biography
Guillaume Amontons
Guillaume Amontons (31 August 1663 – 11 October 1705) was a French scientific instrument inventor and physicist. He was one of the pioneers in studying the problem of friction, that is the resistance to motion where bodies are in contact. Guillaume was born in Paris, France. His father was a lawyer from Normandy who had moved to the French capital. While still young, Guillaume lost his hear
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  • 01 Dec 2022
Topic Review
Ara (Genus)
Ara is a neotropical genus of macaws with eight extant species and at least two extinct species. The genus name was coined by French naturalist Bernard Germain de Lacépède in 1799. It gives its name to and is part of the Arini, or tribe of neotropical parrots. The genus name Ara is derived from the Tupi word ará, an onomatopoeia of the sound a macaw makes. The Ara macaws are large striking parrots with long tails, long narrow wings and vividly coloured plumage. They all have a characteristic bare face patch around the eyes. Males and females have similar plumage. Many of its members are popular in the pet trade, and bird smuggling is a threat to several species.
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  • 12 Oct 2022
Biography
Theodore Harold Maiman
Theodore Harold "Ted" Maiman (July 11, 1927 – May 5, 2007) was an American engineer and physicist who was widely, but not universally, credited with the invention of the laser (Others attribute the invention to Gordon Gould).[1][2][3][4][5][6][7] Maiman's laser led to the subsequent development of many other types of lasers.[8][9] The laser was successfully fired on May 16, 1960. In a July 7,
  • 2.3K
  • 26 Dec 2022
Topic Review
Anomalocaridid
The Anomalocaridids comprise a group of very early marine animals known primarily from fossils found in Cambrian deposits in China , United States , Canada , Poland and Australia . They were long thought to be restricted to this Cambrian time range, but the discovery of large Ordovician specimens has extended this somewhat. The later Devonian Schinderhannes shows many anomalocaridid features. Although originally interpreted as an anomalocaridid-like arthropod, some recent studies suggest that it may represent an anomalocaridid: if so it would extend the group's record by some hundred million years: the non-mineralised anomalocaridid structure means they are absent from the intermediate fossil record. Anomalocaridids are the largest Cambrian animals known—some Chinese forms may have reached 2 m (7 ft) in length—and most of them were probably active carnivores.
  • 2.3K
  • 31 Oct 2022
Biography
Gustave Trouvé
Gustave Pierre Trouvé (2 January 1839 – 27 July 1902) was a France electrical engineer and inventor in the 19th century. Trouvé was born on 2 January 1839 in La Haye-Descartes (Indre-et-Loire, France) and died on 27 July 1902 in Paris. A polymath, he was highly respected for his innovative skill in miniaturization. Gustave Trouvé was born into a modest family, his father, Jacques Trouv
  • 2.3K
  • 11 Nov 2022
Topic Review
Lactobacillus Vaccine
Lactobacillus vaccines are used in the therapy and prophylaxis of non-specific bacterial vaginitis and trichomoniasis. The vaccines consist of specific inactivated strains of Lactobacilli, called "aberrant" strains in the relevant literature dating from the 1980s. These strains were isolated from the vaginal secretions of patients with acute colpitis. The lactobacilli in question are polymorphic, often shortened or coccoid in shape and do not produce an acidic, anti-pathogenic vaginal environment. A colonization with aberrant lactobacilli has been associated with an increased susceptibility to vaginal infections and a high rate of relapse following antimicrobial treatment. Intramuscular administration of inactivated aberrant lactobacilli provokes a humoral immune response. The production of specific antibodies both in serum and in the vaginal secretion has been demonstrated. As a result of the immune stimulation, the abnormal lactobacilli are inhibited, the population of normal, rod-shaped lactobacilli can grow and exert its defense functions against pathogenic microorganisms.
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  • 17 Oct 2022
Biography
Horst Korsching
Horst Korsching (12 August 1912 – 21 March 1998) was a German physicist. He was arrested by the allied British and American Armed Forces and incarcerated at Farm Hall for six months in 1945 under Operation Epsilon. Born in Danzig, Korsching began his studies of physics at the Humboldt University of Berlin in 1932. In 1937, he joined the scientific staff at the Kaiser-Wilhelm Institut für P
  • 2.3K
  • 16 Dec 2022
Biography
Jeffrey Satinover
Jeffrey Burke Satinover (September 4, 1947) is an American psychiatrist, psychoanalyst, and physicist. He is known for books on a number of controversial topics in physics and neuroscience, and on religion, but especially for his writing and public-policy efforts relating to homosexuality, same-sex marriage and the ex-gay movement. Satinover was born in Chicago, Illinois, on September 4, 1947
  • 2.3K
  • 29 Dec 2022
Topic Review
Methods for the Production of Kilobase-Length Single-Stranded DNA
DNA nanoengineering, in particular, DNA origami has potential applications in a variety of areas including, for example, nanoelectronics, biomedical diagnostics, and therapeutics. To fully realize the potential of DNA self-assembly in these and other areas, methods must be available for economical, scalable, and reliable production of single-stranded DNA (ssDNA) scaffolds from virtually any source. Described here are four such methods.
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  • 18 Apr 2022
Topic Review
Pressure Ulcer
Pressure ulcers, also known as pressure sores, bed sores or pressure injuries, are localised damage to the skin and/or underlying tissue that usually occur over a bony prominence as a result of usually long-term pressure, or pressure in combination with shear or friction. The most common sites are the skin overlying the sacrum, coccyx, heels, and hips, though other sites can be affected, such as the elbows, knees, ankles, back of shoulders, or the back of the cranium. Pressure ulcers occur due to pressure applied to soft tissue resulting in completely or partially obstructed blood flow to the soft tissue. Shear is also a cause, as it can pull on blood vessels that feed the skin. Pressure ulcers most commonly develop in individuals who are not moving about, such as those who are on chronic bedrest or consistently use a wheelchair. It is widely believed that other factors can influence the tolerance of skin for pressure and shear, thereby increasing the risk of pressure ulcer development. These factors are protein-calorie malnutrition, microclimate (skin wetness caused by sweating or incontinence), diseases that reduce blood flow to the skin, such as arteriosclerosis, or diseases that reduce the sensation in the skin, such as paralysis or neuropathy. The healing of pressure ulcers may be slowed by the age of the person, medical conditions (such as arteriosclerosis, diabetes or infection), smoking or medications such as anti-inflammatory drugs. Although often prevented and treatable if detected early, pressure ulcers can be very difficult to prevent in critically ill people, frail elders and individuals with impaired mobility such as wheelchair users (especially where spinal injury is involved). Primary prevention is to redistribute pressure by regularly turning the person. The benefit of turning to avoid further sores is well documented since at least the 19th century. In addition to turning and re-positioning the person in the bed or wheelchair, eating a balanced diet with adequate protein and keeping the skin free from exposure to urine and stool is important. The rate of pressure ulcers in hospital settings is high; the prevalence in European hospitals ranges from 8.3% to 23%, and the prevalence was 26% in Canadian healthcare settings from 1990 to 2003. In 2013, there were 29,000 documented deaths from pressure ulcers globally, up from 14,000 deaths in 1990.
  • 2.3K
  • 25 Oct 2022
Biography
Arlie Petters
Arlie Oswald Petters, MBE (born February 8, 1964) is a Belizean-American mathematical physicist, who is the Benjamin Powell Professor of Mathematics and a Professor Physics and Economics at Duke University.[1] Petters is a founder of mathematical astronomy, focusing on problems connected to the interplay of gravity and light and employing tools from astrophysics, cosmology, general relativity, h
  • 2.3K
  • 24 Nov 2022
Topic Review
Eyelash Extensions
Eyelash extensions are used to enhance the length, curliness, fullness, and thickness of natural eyelashes. The extensions may be made from several materials including mink, synthetic, or horse hair. The main method of applying the extensions is by using an adhesive glue to individually stick the extensions to the eyelash line. False eyelashes and eyelash extensions are not the same.
  • 2.3K
  • 28 Nov 2022
Topic Review
Life
Life is the characteristic state of organisms. Properties common to terrestrial organisms (plants, animals, fungi, protists and bacteria) are that they are cellular, carbon-and-water-based with complex organization, having a metabolism, a capacity to grow, respond to stimuli, reproduce and—through natural selection—adapt. An entity with the above properties is considered to be organic life. However, not every definition of life considers all of these properties to be essential. For example, the capacity for descent with modification is often taken as the only essential property of life. This definition notably includes viruses, which do not qualify under narrower definitions as they are acellular and do not metabolise. Broader definitions of life may also include theoretical non-carbon-based life and other alternative biology. The entire Earth contains about 75 billion tons of biomass (life), which lives within various environments within the biosphere.
  • 2.3K
  • 26 Oct 2022
Topic Review
Urinary Incontinence
Urinary incontinence (UI), also known as involuntary urination, is any uncontrolled leakage of urine. It is a common and distressing problem, which may have a large impact on quality of life. It has been identified as an important issue in geriatric health care. The term enuresis is often used to refer to urinary incontinence primarily in children, such as nocturnal enuresis (bed wetting). UI is an example of a stigmatized medical condition, which creates barriers to successful management and makes the problem worse. People may be too embarrassed to seek medical help, and attempt to self-manage the symptom in secrecy from others. Pelvic surgery, pregnancy, childbirth, and menopause are major risk factors. Urinary incontinence is often a result of an underlying medical condition but is under-reported to medical practitioners. There are four main types of incontinence: Treatments include pelvic floor muscle training, bladder training, surgery, and electrical stimulation. Behavioral therapy generally works better than medication for stress and urge incontinence. The benefit of medications is small and long term safety is unclear. Urinary incontinence is more common in older women.
  • 2.3K
  • 18 Nov 2022
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