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Topic Review
Frost Diagram
A Frost diagram or Frost–Ebsworth diagram is a type of graph used by inorganic chemists in electrochemistry to illustrate the relative stability of a number of different oxidation states of a particular substance. The graph illustrates the free energy vs oxidation state of a chemical species. This effect is dependent on pH, so this parameter also must be included. The free energy is determined by the oxidation–reduction half-reactions. The Frost diagram allows easier comprehension of these reduction potentials than the earlier-designed Latimer diagram, because the “lack of additivity of potentials” was confusing. The free energy ΔG° is related to reduction potential E in the graph by given formula: ΔG° = −nFE° or nE° = −ΔG°/F, where n is the number of transferred electrons, and F is Faraday constant (F = 96,485 J/(V·mol)). The Frost diagram is named after Arthur Atwater Frost (de), who originally created it as a way to "show both free energy and oxidation potential data conveniently" in a 1951 paper.
  • 6.7K
  • 01 Dec 2022
Topic Review
Amen
Amen (/ˌɑːˈmɛn/, /ˌeɪˈmɛn/)[lower-alpha 1] (Hebrew אָמֵן, Greek ἀμήν, Arabic آمِينَ, Amharic አሜን) is a declaration of affirmation first found in the Hebrew Bible and subsequently in the New Testament. It is used in Jewish, Christian and Muslim worship as a concluding word or response to prayers. Common English translations of the word amen include "verily", "truly", and “so be it”. It can also be used colloquially to express strong agreement, as in, amen to that.
  • 6.7K
  • 27 Oct 2022
Topic Review
76 Mm Gun M1
The 76 mm gun M1 was an American World War II–era tank gun developed by the U.S Ordnance Department in 1942 to supplement the 75 mm gun on the basic Medium tank M4. It was also used to arm the 76 mm Gun Motor Carriage M18 tank destroyer. Although the gun was tested in early August 1942 and classified on August 17, 1942, it was not until August 1943 that the Ordnance Department developed a mounting for the M4 tank that the tank forces would accept. It was not accepted for combat until July 1944. In January 1943, the decision was made to mount the 76 mm on the vehicle that would become the M18. By May 1944, it was being combat tested as the T70.
  • 6.7K
  • 11 Nov 2022
Topic Review
Non-Ionic Surfactants
Surfactants are essential in the manufacture of polymeric nanoparticles by emulsion formation methods and to preserve the stability of carriers in liquid media. The deposition of non-ionic surfactants at the interface allows a considerable reduction of the globule of the emulsion with high biocompatibility and the possibility of oscillating the final sizes in a wide nanometric range.
  • 6.7K
  • 29 Jun 2021
Topic Review
Royal Ordnance L7
The Royal Ordnance L7 is the basic model of the United Kingdom 's most successful tank gun. The L7 is a 105 mm L/52 rifled design by the Royal Ordnance Factories intended for use in armoured fighting vehicles, replacing the earlier 20-pounder (84 mm) tank gun mounted on the Centurion tank. The successful L7 gun has been fitted on many armored vehicles including the British Centurion (starting from the Mk. 5/2 variant), the German Leopard 1 and early variants of the US M1 Abrams (M1 and M1IP). The L7 is a popular weapon and continued in use even after it was superseded by the L11 series 120 mm rifled tank gun, for some Centurion tanks operating as Artillery Forward Observation and Armoured Vehicle, Royal Engineers (AVRE) vehicles. The L7, and adaptations of it, can be found as standard or retrofitted equipment on a wide variety of tanks developed during the Cold War.
  • 6.7K
  • 08 Nov 2022
Topic Review
Citrus limon (Lemon) Phenomenon
Citrus limon (lemon) is a species with valuable pharmaceutical, cosmetic and culinary (healthy food) properties. The valuable biological activity of C. limon is determined by its high content of phenolic compounds, mainly flavonoids (e.g., diosmin, hesperidin, limocitrin) and phenolic acids (e.g., ferulic, synapic, p-hydroxybenzoic acids). The essential oil is rich in bioactive monoterpenoids such as D-limonene, β-pinene, γ-terpinene. Recently scientifically proven therapeutic activities of C. limon include anti-inflammatory, antimicrobial, anticancer and antiparasitic activities. In view of beneficial properties C. limon  is also used in the food industry and cosmetology. Attention should be pay on safety of use and potential phototoxicity of this raw materials.
  • 6.7K
  • 30 Oct 2020
Topic Review
Varna Necropolis
The so-called Varna Necropolis (Bulgarian: Варненски некропол) (also Varna Cemetery) is a burial site from 4569–4340 BC in the western industrial zone of Varna (approximately half a kilometre from Lake Varna and 4 km from the city centre), internationally considered one of the key archaeological sites in world prehistory. There were other necropoles dating from later Greek and Roman periods around the ancient city. The oldest gold treasure in the world, dating from this period, was discovered at the site.
  • 6.7K
  • 28 Oct 2022
Topic Review
Different Types of Adipocytes
Adipose tissue resides in specific depots scattered in peripheral or deeper locations all over the body and it enwraps most of the organs. This tissue is always in a dynamic evolution as it must adapt to the metabolic demand and constraints. It exhibits also endocrine functions important to regulate energy homeostasis. This complex organ is composed of depots able to produce opposite functions to monitor energy: the so called white adipose tissue acts to store energy as triglycerides preventing ectopic fat deposition while the brown adipose depots dissipate it. It is composed of many cell types. Different types of adipocytes constitute the mature cells specialized to store or burn energy. Immature adipose progenitors (AP) presenting stem cells properties contribute not only to the maintenance but also to the expansion of this tissue as observed in overweight or obese individuals.
  • 6.6K
  • 28 Apr 2021
Topic Review
Modern Stoicism
Modern Stoicism is an intellectual and popular movement that began at the end of the 20th century aimed at reviving the practice of Stoicism. It is not to be confused with neostoicism, an analogous phenomenon in the 17th century. The term "modern Stoicism" covers both the revival of interest in the Stoic philosophy and the philosophical efforts to adjust ancient Stoicism to the language and conceptual framework of the present. The rise of modern Stoicism has received attention in the international media since around November 2012 when the first Annual Stoic Week event was organized.
  • 6.6K
  • 04 Nov 2022
Topic Review
Pharmacological Activities of Indian Camphorweed (Pluchea indica)
Pluchea indica (L.) Less. (Asteraceae) commonly-known as Indian camphorweed, pluchea, or marsh fleabane has gained great importance in various traditional medicines for its nutritional and medicinal benefits. It is utilized to cure several illnesses such as lumbago, kidney stones, leucorrhea, inflammation, gangrenous and atonic ulcer, hemorrhoids, dysentery, eye diseases, itchy skin, acid stomach, dysuria, abdominal pain, scabies, fever, sore muscles, dysentery, diabetes, rheumatism, etc. The plant or its leaves in the form of tea are commonly used for treating diabetes and rheumatism. 
  • 6.6K
  • 25 May 2022
Topic Review
Dukkha
Dukkha (/ˈduːkə/; Pāli; Sanskrit: duḥkha; Tibetan: སྡུག་བསྔལ་ sdug bsngal, pr. "duk-ngel") is an important Buddhist concept, commonly translated as "suffering", "pain", "unsatisfactoriness" or "stress". It refers to the fundamental unsatisfactoriness and painfulness of mundane life. It is the first of the Four Noble Truths. The term is also found in scriptures of Hinduism, such as the Upanishads, in discussions of moksha (spiritual liberation).
  • 6.6K
  • 24 Oct 2022
Topic Review
Man-Eating Plant
A man-eating plant is a legendary carnivorous plant large enough to kill and consume a human or other large animal. Various such myths and fictional tales exist around the world.
  • 6.6K
  • 17 Nov 2022
Topic Review
Allosaurus
Allosaurus (/ˌæləˈsɔːrəs/) is a genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic epoch (Kimmeridgian to late Tithonian). The name "Allosaurus" means "different lizard" alluding to its unique (at the time of its discovery) concave vertebrae. It is derived from the Greek ἄλλος (allos) ("different, other") and σαῦρος (sauros) ("lizard / generic reptile"). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. Allosaurus was a large bipedal predator. Its skull was light, robust and equipped with dozens of sharp, serrated teeth. It averaged 8.5 meters (28 ft) in length for A. fragilis, with the largest specimens estimated as being 9.7 metres (32 ft) long. Relative to the large and powerful hindlimbs, its three-fingered forelimbs were small, and the body was balanced by a long and heavily muscled tail. It is classified as an allosaurid, a type of carnosaurian theropod dinosaur. The genus has a complicated taxonomy, and includes at least three valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains have come from North America's Morrison Formation, with material also known from Portugal. It was known for over half of the 20th century as Antrodemus, but a study of the abundant remains from the Cleveland-Lloyd Dinosaur Quarry brought the name "Allosaurus" back to prominence and established it as one of the best-known dinosaurs. As the most abundant large predator in the Morrison Formation, Allosaurus was at the top of the food chain, probably preying on contemporaneous large herbivorous dinosaurs, and perhaps other predators. Potential prey included ornithopods, stegosaurids, and sauropods. Some paleontologists interpret Allosaurus as having had cooperative social behavior, and hunting in packs, while others believe individuals may have been aggressive toward each other, and that congregations of this genus are the result of lone individuals feeding on the same carcasses.
  • 6.6K
  • 16 Nov 2022
Topic Review
Graphical Projection
Graphical projection is a protocol, used in technical drawing, by which an image of a three-dimensional object is projected onto a planar surface without the aid of numerical calculation.
  • 6.6K
  • 07 Nov 2022
Topic Review
Antioxidants
There are established links between free radicals and more than sixty different human health conditions, including ageing, cancer, diabetes, Alzheimer’s disease, strokes, heart attacks, and atherosclerosis. Consumption of higher levels of dietary antioxidant enzymes and antioxidant molecules-enriched food or antioxidant supplements has been found to reduce the risk of free radical-related health issues. The green halotolerant microalgae Dunaliella can grow in a wide range of saline environments and is a  potential natural source for antioxidant production.
  • 6.6K
  • 10 May 2021
Topic Review
Vulvar and Vaginal Melanomas
Melanomas of the skin are poorly circumscribed lesions, very frequently asymptomatic but unfortunately with a continuous growing incidence. In this landscape, one can distinguish melanomas originating in the mucous membranes and located in areas not exposed to the sun, namely the vulvo-vaginal melanomas. By contrast with cutaneous melanomas, the incidence of these types of melanomas is constant, being diagnosed in females in their late sixties. While hairy skin and glabrous skin melanomas of the vulva account for 5% of all cancers located in the vulva, melanomas of the vagina and urethra are particularly rare conditions. The location in areas less accessible to periodic inspection determines their diagnosis in advanced stages, often metastatic. 
  • 6.6K
  • 22 Sep 2021
Topic Review
Cocoa By-Products
Theobroma cacao L., the cocoa-producing tree, belongs to the order of Malvales, family Malvaceae and genus Theobroma. Its name has Greek origins, Theos and Bromos, meaning “food of the gods”.
  • 6.6K
  • 19 Apr 2022
Topic Review
Central Nervous System in Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a heterogeneous, behaviorally defined, neurodevelopmental disorder that has been modeled as a brain-based disease.
  • 6.6K
  • 20 Jan 2022
Topic Review
Transcription
Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins are said to produce messenger RNA (mRNA). Other segments of DNA are copied into RNA molecules called non-coding RNAs (ncRNAs). Averaged over multiple cell types in a given tissue, the quantity of mRNA is more than 10 times the quantity of ncRNA (though in particular single cell types ncRNAs may exceed mRNAs). The general preponderance of mRNA in cells is valid even though less than 2% of the human genome can be transcribed into mRNA (Human genome), while at least 80% of mammalian genomic DNA can be actively transcribed (in one or more types of cells), with the majority of this 80% considered to be ncRNA. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. Transcription proceeds in the following general steps: If the stretch of DNA is transcribed into an RNA molecule that encodes a protein, the RNA is termed messenger RNA (mRNA); the mRNA, in turn, serves as a template for the protein's synthesis through translation. Other stretches of DNA may be transcribed into small non-coding RNAs such as microRNA, transfer RNA (tRNA), small nucleolar RNA (snoRNA), small nuclear RNA (snRNA), or enzymatic RNA molecules called ribozymes as well as larger non-coding RNAs such as ribosomal RNA (rRNA), and long non-coding RNA (lncRNA). Overall, RNA helps synthesize, regulate, and process proteins; it therefore plays a fundamental role in performing functions within a cell. In virology, the term transcription may also be used when referring to mRNA synthesis from an RNA molecule (i.e., equivalent to RNA replication). For instance, the genome of a negative-sense single-stranded RNA (ssRNA -) virus may be a template for a positive-sense single-stranded RNA (ssRNA +)[clarification needed]. This is because the positive-sense strand contains the sequence information needed to translate the viral proteins needed for viral replication. This process is catalyzed by a viral RNA replicase.[clarification needed]
  • 6.6K
  • 14 Apr 2023
Topic Review
Czochralski Process
The Czochralski process is a method of crystal growth used to obtain single crystals of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The process is named after Polish scientist Jan Czochralski, who invented the method in 1915 while investigating the crystallization rates of metals. He made this discovery by accident: instead of dipping his pen into his inkwell, he dipped it in molten tin, and drew a tin filament, which later proved to be a single crystal. The most important application may be the growth of large cylindrical ingots, or boules, of single crystal silicon used in the electronics industry to make semiconductor devices like integrated circuits. Other semiconductors, such as gallium arsenide, can also be grown by this method, although lower defect densities in this case can be obtained using variants of the Bridgman-Stockbarger technique.
  • 6.6K
  • 24 Nov 2022
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