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Topic Review
Oil Spill Modeling
Several oil spill simulation models exist in the literature, which are used worldwide to simulate the evolution of an oil slick created from marine traffic, petroleum production, or other sources. These models may range from simple parametric calculations to advanced, new-generation, operational, three-dimensional numerical models, coupled to meteorological, hydrodynamic, and wave models, forecasting in high-resolution and with high precision the transport and fate of oil. This study presents a review of the transport and oil weathering processes and their parameterization and critically examines eighteen state-of-the-art oil spill models in terms of their capacity (a) to simulate these processes, (b) to consider oil released from surface or submerged sources, (c) to assimilate real-time field data for model initiation and forcing, and (d) to assess uncertainty in the produced predictions. Based on our review, the most common oil weathering processes involved are spreading, advection, diffusion, evaporation, emulsification, and dispersion. The majority of existing oil spill models do not consider significant physical processes, such as oil dissolution, photo-oxidation, biodegradation, and vertical mixing. Moreover, timely response to oil spills is lacking in the new generation of oil spill models. Further improvements in oil spill modeling should emphasize more comprehensive parametrization of oil dissolution, biodegradation, entrainment, and prediction of oil particles size distribution following wave action and well blow outs.
  • 3.3K
  • 02 Mar 2021
Topic Review
Non-Native Guinea Grass
Guinea grass (Panicum maximum Jacq., renamed Megathyrsus maximus Jacq.) is a native forage plant in Africa of great economic value, but it was introduced in almost all tropical countries as a source of animal forage.
  • 3.3K
  • 30 Jun 2021
Topic Review
Dialysis
In medicine, dialysis (from Greek διάλυσις, dialysis, "dissolution"; from διά, dia, "through", and λύσις, lysis, "loosening or splitting") is the process of removing excess water, solutes, and toxins from the blood in people whose kidneys can no longer perform these functions naturally. This is referred to as renal replacement therapy. The first successful dialysis was performed in 1943. Dialysis may need to be initiated when there is a sudden rapid loss of kidney function, known as acute kidney injury (previously called acute renal failure), or when a gradual decline in kidney function, chronic kidney disease, reaches stage 5. Stage 5 chronic renal failure is reached when the glomerular filtration rate is 10–15% of normal, creatinine clearance is less than 10 mL per minute and uremia is present. Dialysis is used as a temporary measure in either acute kidney injury or in those awaiting kidney transplant and as a permanent measure in those for whom a transplant is not indicated or not possible. In Australia, Canada, the United Kingdom, and the United States, dialysis is paid for by the government for those who are eligible. In research laboratories, dialysis technique can also be used to separate molecules based on their size. Additionally, it can be used to balance buffer between a sample and the solution "dialysis bath" or "dialysate" that the sample is in. For dialysis in a laboratory, a tubular semipermeable membrane made of cellulose acetate or nitrocellulose is used. Pore size is varied according to the size separation required with larger pore sizes allowing larger molecules to pass through the membrane. Solvents, ions and buffer can diffuse easily across the semipermeable membrane, but larger molecules are unable to pass through the pores. This can be used to purify proteins of interest from a complex mixture by removing smaller proteins and molecules.
  • 3.3K
  • 07 Nov 2022
Biography
Edip Yüksel
Edip Yüksel (born December 20, 1957 in Güroymak, Turkey) is a Kurdish American author and philosophy professor of Sunni Muslim background. He is an exponent of the modern Islamic reform and Quranism (Quraniyoon) movements and is known for his criticism and rejection of both Sunni and Shiite versions of Islam. Author of several books on the Qur'an and Islam, he gained attention through his work
  • 3.3K
  • 01 Dec 2022
Topic Review
Antimony as a Critical Raw Material
Antimony is widely acknowledged as a critical raw material of worldwide significance, based on its recognition by many countries. According to current projections, there is an anticipated increase in the demand for antimony in the forthcoming years. An issue of significant concern within the supply chain, which poses a substantial obstacle to sustainable development, is the global unequal allocation of abundant antimony resources. Most nations exhibited a high degree of dependence on a few countries for their net imports of antimony, resulting in a notable disruption and raising concerns regarding the supply chain. 
  • 3.3K
  • 23 Feb 2024
Topic Review
Chemical Modifications of Aptamers
Aptamers are short single-stranded RNA or DNA oligonucleotides capable of folding into complex 3D structures, enabling them to bind to a large variety of targets ranging from small ions to an entire organism. Their high binding specificity and affinity make them comparable to antibodies, but they are superior regarding a longer shelf life, simple production and chemical modification, in addition to low toxicity and immunogenicity.
  • 3.3K
  • 03 Dec 2021
Topic Review
Basis Set
A basis set in theoretical and computational chemistry is a set of functions (called basis functions) that is used to represent the electronic wave function in the Hartree–Fock method or density-functional theory in order to turn the partial differential equations of the model into algebraic equations suitable for efficient implementation on a computer. The use of basis sets is equivalent to the use of an approximate resolution of the identity: the orbitals [math]\displaystyle{ |\psi_i\rangle }[/math] are expanded within the basis set as a linear combination of the basis functions [math]\displaystyle{ |\psi_i\rangle \approx \sum_\mu c_{\mu i} |\mu\rangle }[/math], where the expansion coefficients [math]\displaystyle{ c_{\mu i} }[/math] are given by [math]\displaystyle{ c_{\mu i} = \sum_{\nu} \langle \mu|\nu \rangle^{-1} \langle \nu |\psi_i \rangle }[/math]. The basis set can either be composed of atomic orbitals (yielding the linear combination of atomic orbitals approach), which is the usual choice within the quantum chemistry community; plane waves which are typically used within the solid state community, or real-space approaches. Several types of atomic orbitals can be used: Gaussian-type orbitals, Slater-type orbitals, or numerical atomic orbitals. Out of the three, Gaussian-type orbitals are by far the most often used, as they allow efficient implementations of Post-Hartree–Fock methods.
  • 3.3K
  • 17 Oct 2022
Topic Review
Torii
A torii (鳥居, literally bird abode, Japanese pronunciation: [to.ɾi.i]) is a traditional Japan ese gate most commonly found at the entrance of or within a Shinto shrine, where it symbolically marks the transition from the mundane to sacred. The presence of a torii at the entrance is usually the simplest way to identify Shinto shrines, and a small torii icon represents them on Japanese road maps.[note 1] The first appearance of Torii gates in Japan can be reliably pinpointed to at least the mid-Heian period because they are mentioned in a text written in 922. The oldest existing stone torii was built in the 12th century and belongs to a Hachiman Shrine in Yamagata prefecture. The oldest wooden torii is a ryōbu torii (see description below) at Kubō Hachiman Shrine in Yamanashi prefecture built in 1535. Torii gates were traditionally made from wood or stone, but today they can be also made of reinforced concrete, copper, stainless steel or other materials. They are usually either unpainted or painted vermilion with a black upper lintel. Inari shrines typically have many torii because those who have been successful in business often donate in gratitude a torii to Inari, kami of fertility and industry. Fushimi Inari-taisha in Kyoto has thousands of such torii, each bearing the donor's name.
  • 3.3K
  • 06 Nov 2022
Topic Review
Triboelectric Nanogenerator
First proposed by Wang in 2012, the triboelectric nanogenerator (TENG, also called Wang generator) derived from Maxwell’s displacement current shows great prospect as a new technology to convert mechanical energy into electricity, based on the triboelectrification effect and electrostatic induction. TENGs present superiorities including light weight, cost-effectiveness, easy fabrication, and versatile material choices. The concept of harvesting blue energy using the TENG and its network was first brought out in 2014. As a new form of blue energy harvester, the TENG surpasses the EMG in that it intrinsically displays higher effectiveness under low frequency, owing to the unique feature of its output characteristics. Moreover, adopting the distributed architecture of light-weighted TENG networks can make it more suitable for collecting wave energy of high entropy compared with EMGs, which are oversized in volume and mass.
  • 3.3K
  • 13 Sep 2021
Topic Review
Eurypterida
Eurypterids, often informally called sea scorpions, are a group of extinct arthropods that form the order Eurypterida. The earliest known eurypterids date to the Darriwilian stage of the Ordovician period 467.3 million years ago. The group is likely to have appeared first either during the Early Ordovician or Late Cambrian period. With approximately 250 species, the Eurypterida is the most diverse Paleozoic chelicerate order. Following their appearance during the Ordovician, eurypterids became major components of marine faunas during the Silurian, from which the majority of eurypterid species have been described. The Silurian genus Eurypterus accounts for more than 90% of all known eurypterid specimens. Though the group continued to diversify during the subsequent Devonian period, the eurypterids were heavily affected by the Late Devonian extinction event. They declined in numbers and diversity until becoming extinct during the Permian–Triassic extinction event (or sometime shortly before) 251.9 million years ago. Although popularly called "sea scorpions", only the earliest eurypterids were marine; many later forms lived in brackish or fresh water, and they were not true scorpions. Some studies suggest that a dual respiratory system was present, which would have allowed for short periods of time in terrestrial environments. The name Eurypterida comes from the Ancient Greek words εὐρύς (eurús), meaning 'broad' or 'wide', and πτερόν (pterón), meaning 'wing', referring to the pair of wide swimming appendages present in many members of the group. The eurypterids include the largest known arthropods ever to have lived. The largest, Jaekelopterus, reached 2.5 meters (8.2 ft) in length. Eurypterids were not uniformly large and most species were less than 20 centimeters (8 in) long; the smallest eurypterid, Alkenopterus, was only 2.03 centimeters (0.80 in) long. Eurypterid fossils have been recovered from every continent. A majority of fossils are from fossil sites in North America and Europe because the group lived primarily in the waters around and within the ancient supercontinent of Euramerica. Only a handful of eurypterid groups spread beyond the confines of Euramerica and a few genera, such as Adelophthalmus and Pterygotus, achieved a cosmopolitan distribution with fossils being found worldwide.
  • 3.3K
  • 25 Nov 2022
Topic Review
Fabrication Processes of Conductive Textiles
Wearable electronics are gaining popularity as a platform for the next generation of human-friendly electronic devices. Therefore, a new class of devices with various functionality and amenability for the human body is essential. Traditional textile materials, such as fiber, yarn, and fabric, are non-conductive. Innovative methods and novel processing technologies have been introduced to impart conductivity in textile materials to solve this issue. Coating, printing, deposition, and in situ polymerization are common techniques for this purpose. Here, the newly developed methods with significant potential are summarized, which includes their conductivity level in different applications, such as batteries, displays, and sensors.
  • 3.3K
  • 04 Jan 2023
Topic Review
Oldest People
This is a list of tables of the oldest people in the world in ordinal ranks. To avoid including false or unconfirmed claims of extreme old age, names here are restricted to those people whose ages have been validated by an international body that specifically deals in longevity research, such as the Gerontology Research Group (GRG) or Guinness World Records (GWR), and others who have otherwise been reliably sourced. According to this criterion, the longest human lifespan is that of Jeanne Calment of France (1875–1997), who lived to the age of 122 years, 164 days. She met Vincent van Gogh when she was 12 or 13. She received news media attention in 1985, after turning 110. Subsequent investigation found documentation for Calment's age, beyond any reasonable question, in the records of her native city, Arles, France. More evidence of Calment's lifespan has been produced than for any other supercentenarian, such that her case serves as an archetype in the methodology for verifying the ages of the world's oldest people. As women live longer than men on average, combined records for both sexes are predominated by women. The longest undisputed lifespan for a man is that of Jiroemon Kimura of Japan (1897–2013), who died at age 116 years, 54 days. Since the death of 117-year-old Chiyo Miyako of Japan on 22 July 2018, 115-year-old Kane Tanaka, also of Japan, born 2 January 1903, is the oldest living person in the world whose age has been documented. Since the death of 113-year-old Francisco Núñez Olivera of Spain on 29 January 2018, 113-year-old Masazō Nonaka of Japan, born 25 July 1905, is the world's oldest verified living man.
  • 3.3K
  • 30 Nov 2022
Biography
Neil Peart
Neil Ellwood Peart OC (/pɪərt/; September 12, 1952 – January 7, 2020) was a Canadian musician, songwriter, and author, best known as the drummer and primary lyricist of the rock band Rush. Peart earned numerous awards for his musical performances, including an induction into the Modern Drummer Readers Poll Hall of Fame in 1983, making him the youngest person ever so honoured.[1] His drumming
  • 3.3K
  • 16 Nov 2022
Topic Review
Malaria
Malaria is a severe disease caused by parasites of the genus Plasmodium, which is transmitted to humans by a bite of an infected female mosquito of the species Anopheles. Malaria remains the leading cause of mortality around the world, and early diagnosis and fast-acting treatment prevent unwanted outcomes. It is the most common disease in Africa and some countries of Asia, while in the developed world malaria occurs as imported from endemic areas. The sweet sagewort plant was used as early as the second century BC to treat malaria fever in China. Much later, quinine started being used as an antimalaria drug. A global battle against malaria started in 1955. The World Health Organization carries out a malaria control program on a global scale, focusing on local strengthening of primary health care, early diagnosis of the disease, timely treatment, and disease prevention. Globally, the burden of malaria is lower than ten years ago. However, in the last few years, there has been an increase in the number of malaria cases around the world. It is moving towards targets established by the WHO, but that progress has slowed down.
  • 3.3K
  • 17 Feb 2021
Topic Review
Phenolic Antioxidants and Human Health
Consumers increasingly prefer and seek food and beverages, which, due to their natural characteristics, bring health benefits, both in the prevention of diseases and in their curative power. In this way, the production of nutraceutical foods and beverages gains more and more importance in the market. On the other hand, and because the eyes also eat, producing attractive foods due to their color, texture, appearance, and sensory characteristics is a permanent challenge in the food industry. Being able to gather healthy and attractive items in a single food is an even greater challenge. The long list of benefits associated with phenolic compounds, such as antioxidant, anticancer, anti-inflammatory, and antiaging properties, among others, fully justifies their use in the enrichment of various food products. 
  • 3.3K
  • 14 Mar 2021
Topic Review
Classic Car
A classic car is an older automobile; the exact definition varies around the world. The common theme is of an older car with enough historical interest to be collectable and worth preserving or restoring rather than scrapping. Cars 20 years and older typically fall into the classic class. Organizations such as the Classic Car Club of America (CCCA) and the Antique Automobile Club of America (AACA) maintain a list of eligible unmodified cars that are called "classic". These are described as "fine" or "distinctive" automobile, either American or foreign built, produced between 1915 to 1998. Post–World War II "classic cars" are not precisely defined and the term is often applied to any older vehicle.
  • 3.3K
  • 02 Nov 2022
Topic Review
Host Defenses to Viruses
The constant battle between viruses and their hosts leads to their reciprocal evolution. Viruses regularly develop survival strategies against host immunity, while their ability to replicate and disseminate is countered by the antiviral defense mechanisms that host mount. Although most viral infections are generally controlled by the host’s immune system, some viruses do cause overt damage to the host. The outcome can vary widely depending on the properties of the infecting virus and the circumstances of infection but also depends on several factors controlled by the host, including host genetic susceptibility to viral infections.
  • 3.3K
  • 16 Feb 2022
Topic Review
Novichok Agent
A Novichok agent (Russian: Новичо́к, "newcomer", "novice", "newbie") is a group of nerve agents, some of which are binary chemical weapons. The agents were developed at the GosNIIOKhT state chemical research institute by the Soviet Union and Russia between 1971 and 1993.[lower-alpha 1] Some Novichok agents at STP are solids while others are liquids. It is thought that dispersal for the solids is possible by ultrafine powder. Russian scientists who developed the nerve agents claim they are the deadliest ever made, with some variants possibly five to eight times more potent than VX, and others up to ten times more potent than soman. As well as Russia, Novichok agents have been known to be produced in Iran. In the 21st century, Novichok agents came to public attention after they were used to poison opponents of the Russian government, including the Skripals and two others in Amesbury, UK (2018) and Alexei Navalny (2020), but civil poisonings with this substance have been known since at least 1995. In November 2019, the Organisation for the Prohibition of Chemical Weapons (OPCW), which is the executive body for the Chemical Weapons Convention (CWC), added the Novichok agents to "list of controlled substances" of the CWC "in one of the first major changes to the treaty since it was agreed in the 1990s" in response to the 2018 poisonings in the UK.
  • 3.3K
  • 11 Nov 2022
Topic Review
Cyanomethylation Reaction
Cyanomethylation is very useful in organic synthesis because the cyano groups can be hydrolyzed to carboxylic acids and reduced to amines, from which other functional groups can be derived. In addition, the cyano group is the structural unit of many drugs, such as piritramide, diphenozlate, and gallopamil, while acetonitrile is an ideal source of the cyanomethyl functional group due to the difficulty in breaking the C-CN bond. 
  • 3.3K
  • 08 May 2023
Topic Review
Sponge
Sponges, the members of the phylum Porifera (/pəˈrɪfərə/; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. Sponges were first to branch off the evolutionary tree from the last common ancestor of all animals, making them the sister group of all other animals.
  • 3.3K
  • 22 Nov 2022
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