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Topic Review
Scorpion Sting
A scorpion sting is an injury caused by the stinger of a scorpion resulting in the medical condition known as scorpionism, which may vary in severity. The anatomical part of the scorpion that delivers the sting is called a "telson". In typical cases, scorpion stings usually result in pain, paresthesia, and variable swelling. In serious cases, scorpion stings may involve the envenomation of humans by toxic scorpions, which may result in extreme pain, serious illness, or even death depending on the toxicity of the venom. Most scorpion stings range in severity from minor swelling to medically significant lesions, with only a few able to cause severe allergic, neurotic or necrotic reactions. However, scorpion stings account for approximately 3,000 deaths a year worldwide. The Brazilian yellow scorpion (Tityus serrulatus) is one species known for being especially dangerous, being responsible for most scorpion sting fatalities in South America. Scorpion stings are seen all over the world but are predominantly seen in the tropical and subtropical areas. In the Western hemisphere, these areas include Mexico, northern South America and southeast Brazil . In the Eastern hemisphere, these regions include Sub-Saharan Africa, the Middle East, and the Indian subcontinent.
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Topic Review
Rhamnus (Genus)
Rhamnus is a genus of about 110 accepted species of shrubs or small trees, commonly known as buckthorns in the family Rhamnaceae. Its species range from 1 to 10 meters tall (rarely to 15 m) and are native mainly in east Asia and North America, but found throughout the temperate and subtropical Northern Hemisphere, and also more locally in the subtropical Southern Hemisphere in parts of Africa and South America. Both deciduous and evergreen species occur. The leaves are simple, 3 to 15 centimeters long, and arranged alternately or in opposite pairs, or almost paired (subopposite). One distinctive character of many buckthorns is the way the veination curves upward towards the tip of the leaf. The plant bears fruits which are black or red berry-like drupe. The name is due to the woody spine on the end of each twig in many species. In the United States , Buckthorn is considered an invasive species by many local jurisdictions and state governments, such as Minnesota or Wisconsin.
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Topic Review
Organic Peroxide
Organic peroxides are organic compounds containing the peroxide functional group (ROOR′). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. Peresters are the peroxy analog of esters and have general structure RC(O)OOR. The O−O bond of peroxides easily breaks, producing free radicals of the form RO• (the dot represents an unpaired electron). Thus, organic peroxides are useful as initiators for some types of polymerisation, such as the epoxy resins used in glass-reinforced plastics. MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can either intentionally or unintentionally initiate explosive polymerisation in materials with unsaturated chemical bonds, and this process has been used in explosives. Organic peroxides, like their inorganic counterparts, are powerful bleaching agents.
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Topic Review
Ocimum Species
Ocimum is known to be one of the medicinal plants that have been used traditionally by local people. This plant contains components of secondary metabolites such as phenolics, flavonoids, steroids, terpenoids, and alkaloids.
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Topic Review
Stacking
In chemistry, pi stacking (also called π–π stacking) refers to attractive, noncovalent interactions between aromatic rings, since they contain pi bonds. These interactions are important in nucleobase stacking within DNA and RNA molecules, protein folding, template-directed synthesis, materials science, and molecular recognition, although new research suggests that pi stacking may not be operative in some of these applications. Despite intense experimental and theoretical interest, there is no unified description of the factors that contribute to pi stacking interactions.
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Topic Review
Metals in Medicine
Metals in medicine are used in organic systems for diagnostic and treatment purposes. Inorganic elements are also essential for organic life as cofactors in enzymes called metalloproteins. When metals are scarce or high quantities, equilibrium is set out of balance and must be returned to its natural state via interventional and natural methods.
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Topic Review
Smiles Arbitrary Target Specification
SMiles ARbitrary Target Specification (SMARTS) is a language for specifying substructural patterns in molecules. The SMARTS line notation is expressive and allows extremely precise and transparent substructural specification and atom typing. SMARTS is related to the SMILES line notation that is used to encode molecular structures and like SMILES was originally developed by David Weininger and colleagues at Daylight Chemical Information Systems. The most comprehensive descriptions of the SMARTS language can be found in Daylight's SMARTS theory manual, tutorial and examples. OpenEye Scientific Software has developed their own version of SMARTS which differs from the original Daylight version in how the R descriptor (see cyclicity below) is defined. The standard may require updates to accommodate for new the elements named in 2016.
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Topic Review
International Geo Sample Number
The International Geo Sample Number or IGSN is a persistent identifier for sample. As an active persistent identifier it can be resolved through the Handle System. The system is used in production by the System for Earth Sample Registration (SESAR), Geoscience Australia, Commonwealth Scientific and Industrial Research Organisation Mineral Resources, Australian Research Data Commons (ARDC), University of Bremen MARUM, German Research Centre for Geosciences (GFZ), IFREMER Institut Français de Recherche pour l'Exploitation de la Mer, Korea Institute of Geoscience & Mineral Resources (KIGAM), and University of Kiel. Other organisations are preparing the introduction of the IGSN. The IGSN was developed as the International Geo Sample Number to provide a persistent, globally unique, web resolvable identifier for physical samples. IGSN is both a governance and technical system for assigning globally unique persistent identifiers to physical samples. Even though initially developed for samples in the geosciences, the application of IGSN can be and has already been expanded to other domains that rely on physical samples and collections. The IGSN preserves the identity of a sample even as it is moved from lab to lab and as data appear in different publications, thus eliminating ambiguity that stems from similar names for samples from the earth. The IGSN unique identifier allows researchers to track the analytical history of a sample and build on previously collected data as new techniques are developed. Additionally, the IGSN provides a link between disparate data generated by different investigators and published in different scientific articles. In September 2021, the members of IGSN e.V. and DataCite agreed to enter a partnership. Under the partnership, DataCite will provide the IGSN ID registration services and supporting technology to enable the ongoing sustainability of the IGSN PID infrastructure. The IGSN e.V. will facilitate a Community of Communities to promote and support new research and innovation for standard methods of identifying, citing, and locating physical samples. To take into account the expanded scope of the application of IGSN beyond the earth and environmental sciences, the IGSN Implementation Organization (IGSN e.V.) voted to change the name of the identifier to International Generic Sample Number (IGSN) and rename the organisation accordingly.
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Topic Review
Amalgam
An amalgam is an alloy of mercury with another metal. It may be a liquid, a soft paste or a solid, depending upon the proportion of mercury. These alloys are formed through metallic bonding, with the electrostatic attractive force of the conduction electrons working to bind all the positively charged metal ions together into a crystal lattice structure. Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. Silver-mercury amalgams are important in dentistry, and gold-mercury amalgam is used in the extraction of gold from ore. Dentistry has used alloys of mercury with metals such as silver, copper, indium, tin and zinc.
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Topic Review
H2 Antagonist
H2 antagonists, sometimes referred to as H2RAs and also called H2 blockers, are a class of medications that block the action of histamine at the histamine H2 receptors of the parietal cells in the stomach. This decreases the production of stomach acid. H2 antagonists can be used in the treatment of dyspepsia, peptic ulcers and gastroesophageal reflux disease. They have been surpassed by proton pump inhibitors (PPIs); the PPI omeprazole was found to be more effective at both healing and alleviating symptoms of ulcers and reflux oesophagitis than the H2 blockers ranitidine and cimetidine. H2 antagonists are a type of antihistamine, although in common use the term "antihistamine" is often reserved for H1 antagonists, which relieve allergic reactions. Like the H1 antagonists, some H2 antagonists function as inverse agonists rather than receptor antagonists, due to the constitutive activity of these receptors. The prototypical H2 antagonist, called cimetidine, was developed by Sir James Black at Smith, Kline & French – now GlaxoSmithKline – in the mid-to-late 1960s. It was first marketed in 1976 and sold under the trade name Tagamet, which became the first blockbuster drug. The use of quantitative structure-activity relationships (QSAR) led to the development of other agents – starting with ranitidine, first sold as Zantac, which has fewer adverse effects and drug interactions and is more potent. H2 blockers, which all end in "-tidine," are not the same as H1 receptor antagonists, which relieve allergy symptoms.
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