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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.
  • 2.4K
  • 12 Oct 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
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.
  • 2.4K
  • 26 Oct 2022
Topic Review
Thousand-Year Rose
The Thousand-year Rose (German: Tausendjähriger Rosenstock, literally: Thousand-year-old Rosebush) is also known as the Rose of Hildesheim. It grows on the apse of the Hildesheim Cathedral, a Catholic cathedral in Hildesheim, Germany, that is dedicated to the Assumption of Mary. The cathedral and the adjacent St. Michael's Church have been on the UNESCO list of World Heritage Sites since 1985. The rose that climbs on the wall of the cathedral's apse is believed to be the oldest living rose in the world. A Rosa canina, commonly known as a wild dog rose, grows against the eastern apse of the cathedral, which is around 21 metres (69 ft) high and 9 metres (30 ft) wide. The rose bush reaches a height of around 10 metres (33 ft) and documentation verifies its age at approximately 700 years. Slight variations arise in the tale of the establishment of the diocese by King Louis the Pious at Hildesheim in 815 but the rose bush is a common theme in all versions. The cathedral was destroyed by Allied bombers in 1945 during the Second World War, but the roots of the rose bush survived and it blossomed again among the ruins. According to legend, while the rose bush flourishes, Hildesheim will prosper. A poem about the rose was published in 1896. In the early twentieth century, after visiting the cathedral and seeing the rose, author Mabel Wagnalls was inspired to write a book, which went on to form the basis of a silent film.
  • 2.4K
  • 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
Cerebrospinal Fluid Leak
A cerebrospinal fluid leak (CSF leak or CSFL) is a medical condition where the cerebrospinal fluid (CSF) surrounding the brain or spinal cord leaks out of one or more holes or tears in the dura mater. A cerebrospinal fluid leak can be either cranial or spinal, and these are two different disorders. A spinal CSF leak can be caused by one or more meningeal diverticula or CSF-venous fistulas not associated with an epidural leak. A CSF leak is either caused by trauma including that arising from medical interventions or spontaneously sometimes in those with predisposing conditions (known as a spontaneous cerebrospinal fluid leak or sCSF leak). Traumatic causes include a lumbar puncture noted by a post-dural-puncture headache, or a fall or other accident. Spontaneous CSF leaks are associated with heritable connective tissue disorders including Marfan syndrome and Ehlers–Danlos syndromes. A loss of CSF greater than its rate of production leads to a decreased volume inside the skull known as intracranial hypotension. Any CSF leak is most often characterized by orthostatic headaches, which worsen when standing, and improve when lying down. Other symptoms can include neck pain or stiffness, nausea, vomiting, dizziness, fatigue, and a metallic taste in the mouth. A CT myelography scan can identify the site of a cerebrospinal fluid leakage. Once identified, the leak can often be repaired by an epidural blood patch, an injection of the patient's own blood at the site of the leak, a fibrin glue injection, or surgery. The set of symptoms associated with a sCSF leak is referred to as a spontaneous cerebrospinal fluid leak syndrome (SCSFLS). A sCSF leak is uncommon but not rare, affecting at least one in 20,000 people and many more who go undiagnosed every year. On average, the condition develops at age 42, and women are twice as likely to be affected. Some people with a sCSF leak have a chronic leak of cerebrospinal fluid despite repeated patching attempts, leading to long-term disability due to pain and being unable to be upright, and surgery is often needed. SCSFLS was first described by German neurologist Georg Schaltenbrand in 1938 and by American neurologist Henry Woltman of the Mayo Clinic in the 1950s.
  • 2.4K
  • 11 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
  • 2.4K
  • 11 Nov 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.
  • 2.4K
  • 31 Oct 2022
Topic Review
Interferon Gamma
Interferon gamma (IFN-γ) is a dimerized soluble cytokine that is the only member of the type II class of interferons. The existence of this interferon, which early in its history was known as immune interferon, was described by E. F. Wheelock as a product of human leukocytes stimulated with phytohemagglutinin, and by others as a product of antigen-stimulated lymphocytes. It was also shown to be produced in human lymphocytes. or tuberculin-sensitized mouse peritoneal lymphocytes challenged with Mantoux test (PPD); the resulting supernatants were shown to inhibit growth of vesicular stomatitis virus. Those reports also contained the basic observation underlying the now widely employed IFN-γ release assay used to test for tuberculosis. In humans, the IFN-γ protein is encoded by the IFNG gene.
  • 2.4K
  • 28 Apr 2023
Topic Review
List of Vaccine Topics
This is a list of vaccine-related topics. A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins. The agent stimulates the body's immune system to recognize the agent as foreign, destroy it, and "remember" it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters.
  • 2.4K
  • 04 Nov 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.
  • 2.4K
  • 18 Apr 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
  • 2.4K
  • 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.
  • 2.4K
  • 22 Nov 2022
Biography
Stephen Emmott
Stephen Emmott (born 3 June 1960) is a British scientist, entrepreneur and chief scientist of Scientific.[1][2] Emmott was named one of London's most influential scientists, and one of the most influential people in London by the Evening Standard in 2012.[3] Emmott studied at the University of York, where he completed a B.Sc. in Biological Sciences (experimental psychology), graduating in 198
  • 2.4K
  • 30 Dec 2022
Biography
Josh Tillman
Joshua Michael Tillman[1] (born May 3, 1981), also known as Father John Misty and previously J. Tillman, is an American singer-songwriter, musician, and record producer.[2] Maintaining a steady output of solo recordings since 2004,[3] Tillman had been a member of or toured with Demon Hunter, Saxon Shore, Fleet Foxes, Jeffertitti's Nile,[4] Pearly Gate Music,[5] Siberian,[6] Har Mar Superstar,[7
  • 2.4K
  • 15 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.
  • 2.4K
  • 08 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.
  • 2.4K
  • 26 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
Biography
Hajo Meyer
File:My good fortune in Auschwitz.webm Hajo Meyer (born Hans Joachim Gustav Meyer; 12 August 1924 – 23 August 2014) was a Germany -born Dutch physicist, Holocaust survivor and anti-Zionist political activist.[1][2] Meyer was born in Bielefeld, the son of Therese (Melchior) and Gustav Meyer, a notary, who had fought in the First World War.[3] Meyer was Jewish.[4] Aged 14, he was sent by his
  • 2.3K
  • 26 Dec 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
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