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Topic Review
Microalgae in Global CO2 Sequestration
The rising concentration of global atmospheric carbon dioxide (CO2) has severely affected our planet’s homeostasis. Efforts are being made worldwide to curb carbon dioxide emissions, but there is still no strategy or technology available to date that is widely accepted. 
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  • 10 Dec 2021
Topic Review
Avalokiteśvara
Avalokiteśvara or Padmapani (/ˌʌvəloʊkɪˈteɪʃvərə/ UV-əl-oh-kih-TAY-shvər-ə; Sanskrit: अवलोकितेश्वर) is a bodhisattva who embodies the compassion of all Buddhas. This bodhisattva is variably depicted, described and portrayed in different cultures as either male or female. In Tibet, he is known as Chenrezik, and in Cambodia as អវលោកិតេស្វរៈ.Cite error: Invalid tag; refs with no name must have content In Chinese Buddhism, Avalokiteśvara has evolved into the somewhat different female figure Guanyin. In Japan this figure is known as Kanzeon or Kannon.
  • 4.7K
  • 17 Oct 2022
Topic Review
Application of Hydrogen Storage Tanks
The most practical way of storing hydrogen gas for fuel cell vehicles is to use a composite overwrapped pressure vessel. Depending on the driving distance range and power requirement of the vehicles, there can be various operational pressure and volume capacity of the tanks, ranging from passenger vehicles to heavy-duty trucks. The current commercial hydrogen storage method for vehicles involves storing compressed hydrogen gas in high-pressure tanks at pressures of 700 bar for passenger vehicles and 350 bar to 700 bar for heavy-duty trucks. In particular, hydrogen is stored in rapidly refillable onboard tanks, meeting the driving range needs of heavy-duty applications, such as regional and line-haul trucking.
  • 4.7K
  • 28 Jul 2023
Topic Review
Cactaceae
The cactus family is a diverse plant group, native to the Americas. Most of the species included have very variable stem shapes, with singular geometric forms, one of the characteristics why they are considered interesting or even bizarre plants. Cacti vegetative organs have adaptations to arid ecosystems, while possessing showy and beautiful flowers. This set of characteristics has made them very popular among specialists and amateurs. In this entry we address some of the generalities of cacti, focusing on the particular modifications present in their flowers. These peculiarities  make them an interesting model to study the development and evolution of these structures. 
  • 4.7K
  • 21 Jun 2021
Topic Review
Competition
Competition is an interaction between organisms or species in which both require a resource that is in limited supply (such as food, water, or territory). Competition lowers the fitness of both organisms involved, since the presence of one of the organisms always reduces the amount of the resource available to the other. In the study of community ecology, competition within and between members of a species is an important biological interaction. Competition is one of many interacting biotic and abiotic factors that affect community structure, species diversity, and population dynamics (shifts in a population over time). There are three major mechanisms of competition: interference, exploitation, and apparent competition (in order from most direct to least direct). Interference and exploitation competition can be classed as "real" forms of competition, while apparent competition is not, as organisms do not share a resource, but instead share a predator. Competition among members of the same species is known as intraspecific competition, while competition between individuals of different species is known as interspecific competition. According to the competitive exclusion principle, species less suited to compete for resources must either adapt or die out, although competitive exclusion is rarely found in natural ecosystems. According to evolutionary theory, competition within and between species for resources is important in natural selection. More recently, however, researchers have suggested that evolutionary biodiversity for vertebrates has been driven not by competition between organisms, but by these animals adapting to colonize empty livable space; this is termed the 'Room to Roam' hypothesis.
  • 4.7K
  • 28 Nov 2022
Topic Review
Halophytes of the Mediterranean Basin
Halophytes represent an ancient and remarkable ecological group of annual or perennial plants with very complex features, whose definition and classification are still not univocal and often controversial. The species belonging to this group are very different from an ecological, morpho–physiological, and taxonomic point of view. Therefore, their definition can be subjective and vary a lot in the literature according to the different interpretations. However, following the most popular definition used in the literature, halophytes can be identified as plants that grow naturally, and complete their life cycle in environments that contain a higher salt content than most plant species can tolerate.
  • 4.7K
  • 23 Mar 2022
Topic Review
Biomarkers in FLT3 Acute Myeloid Leukemia
Acute myeloid leukemia (AML) is a disease characterized by uncontrolled proliferation of clonal myeloid blast cells that are incapable of maturation to leukocytes. AML is the most common leukemia in adults and remains a highly fatal disease with a five-year survival rate of 24%. More than 50% of AML patients have mutations in the FLT3 gene, rendering FLT3 an attractive target for small-molecule inhibition. Currently, there are several FLT3 inhibitors in the clinic, and others remain in clinical trials. However, these inhibitors face challenges due to lack of efficacy against several FLT3 mutants. Therefore, the identification of biomarkers is vital to stratify AML patients and target AML patient population with a particular FLT3 mutation.
  • 4.7K
  • 03 Mar 2022
Topic Review
Growth Factors Regulation in Angiogenesis
Cardiovascular disease (CVD) remains a major cause of morbidity and mortality all over the world. Angiogenesis is controlled by cell–cell and cell-extracellular matrix (ECM) interactions through crosstalk between vascular endothelial growth factor (VEGF) and Notch signaling mechanisms. 
  • 4.7K
  • 31 May 2023
Topic Review
NAFLD and Cardiovascular Comorbidities
Non-alcoholic fatty liver disease (NAFLD) is a liver disease that can progress from hepatic steatosis to steatohepatitis and even cirrhosis and hepatocellular carcinoma. From the histopathological point of view, it is characterized by excess storage of macrovesicular fat in hepatocytes. These macrovesicular storages are composed of triglycerides that accumulate in the liver. The process can lead in some individuals to an inflammatory response, which is responsible for steatohepatitis, that leads to fibrosis and, finally, cirrhosis.NAFLD has a growing prevalence in recent years. Its association with cardiovascular disease has been intensively studied, and certain correlations have been identified. The connection between these two entities has lately aroused interest regarding therapeutic management. 
  • 4.7K
  • 07 May 2021
Topic Review
Smallpox Vaccine
The smallpox vaccine is the first vaccine to be developed against a contagious disease. In 1796, the British doctor Edward Jenner demonstrated that an infection with the relatively mild cowpox virus conferred immunity against the deadly smallpox virus. Cowpox served as a natural vaccine until the modern smallpox vaccine emerged in the 20th century. From 1958 to 1977, the World Health Organization (WHO) conducted a global vaccination campaign that eradicated smallpox, making it the only human disease to be eradicated. Although routine smallpox vaccination is no longer performed on the general public, the vaccine is still being produced to guard against bioterrorism, biological warfare, and monkeypox. The term vaccine derives from the Latin word for cow, reflecting the origins of smallpox vaccination. Edward Jenner referred to cowpox as variolae vaccinae (smallpox of the cow). The origins of the smallpox vaccine became murky over time, especially after Louis Pasteur developed laboratory techniques for creating vaccines in the 19th century. Allan Watt Downie demonstrated in 1939 that the modern smallpox vaccine was serologically distinct from cowpox, and vaccinia was subsequently recognized as a separate viral species. Whole-genome sequencing has revealed that vaccinia is most closely related to horsepox, and the cowpox strains found in Great Britain are the least closely related to vaccinia.
  • 4.7K
  • 14 Apr 2023
Topic Review
Prussian Blue
Efficient water remediation methods towards the extraction of 137Cs are being studied. Prussian blue (PB) and its analogs have shown very high efficiencies in the capture of 137Cs+ ions.
  • 4.7K
  • 07 Jun 2021
Topic Review
Bicentric Quadrilateral
In Euclidean geometry, a bicentric quadrilateral is a convex quadrilateral that has both an incircle and a circumcircle. The radii and center of these circles are called inradius and circumradius, and incenter and circumcenter respectively. From the definition it follows that bicentric quadrilaterals have all the properties of both tangential quadrilaterals and cyclic quadrilaterals. Other names for these quadrilaterals are chord-tangent quadrilateral and inscribed and circumscribed quadrilateral. It has also rarely been called a double circle quadrilateral and double scribed quadrilateral. If two circles, one within the other, are the incircle and the circumcircle of a bicentric quadrilateral, then every point on the circumcircle is the vertex of a bicentric quadrilateral having the same incircle and circumcircle. This is a corollary of Poncelet's porism, which was proved by the French mathematician Jean-Victor Poncelet (1788–1867).
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  • 02 Nov 2022
Topic Review
List of Aircraft (H)
This is a list of aircraft in alphabetical order beginning with 'H'.
  • 4.7K
  • 08 Nov 2022
Topic Review
Degrees of Freedom (Physics and Chemistry)
In physics and chemistry, a degree of freedom is an independent physical parameter in the formal description of the state of a physical system. The set of all states of a system is known as the system's phase space, and the degrees of freedom of the system are the dimensions of the phase space. The location of a particle in three-dimensional space requires three position coordinates. Similarly, the direction and speed at which a particle moves can be described in terms of three velocity components, each in reference to the three dimensions of space. If the time evolution of the system is deterministic (where the state at one instant uniquely determines its past and future position and velocity as a function of time) such a system has six degrees of freedom. If the motion of the particle is constrained to a lower number of dimensions – for example, the particle must move along a wire or on a fixed surface – then the system has fewer than six degrees of freedom. On the other hand, a system with an extended object that can rotate or vibrate can have more than six degrees of freedom. In classical mechanics, the state of a point particle at any given time is often described with position and velocity coordinates in the Lagrangian formalism, or with position and momentum coordinates in the Hamiltonian formalism. In statistical mechanics, a degree of freedom is a single scalar number describing the microstate of a system. The specification of all microstates of a system is a point in the system's phase space. In the 3D ideal chain model in chemistry, two angles are necessary to describe the orientation of each monomer. It is often useful to specify quadratic degrees of freedom. These are degrees of freedom that contribute in a quadratic function to the energy of the system. Depending on what one is counting, there are several different ways that degrees of freedom can be defined, each with a different value.
  • 4.7K
  • 25 Nov 2022
Topic Review
Techniques of Making Edible Coatings
Edible coatings are made from natural food-grade materials, such as hydrocolloids (polysaccharides, proteins), lipids, and emulsifiers, produced with different techniques, such as dipping (immersing), spraying, spreading, brushing, pressing them/thermoforming, or extrusion. The most used method for coating is immersing, where food is dipped in a liquid containing food matrices, forming a film around the food and protecting all the components present.
  • 4.7K
  • 15 Sep 2023
Topic Review
School of Economic Science
Coordinates: 51°31′00″N 0°09′05″W / 51.516775°N 0.151407°W / 51.516775; -0.151407 The School of Economic Science (SES), also operating under the names School of Philosophy and the School of Practical Philosophy, is a worldwide organisation based in London. It offers non-academic courses for adults, ranging from an introductory series called Practical Philosophy to more advanced classes. Its teachings are principally influenced by Advaita Vedanta, an orthodox philosophical system of Hinduism. It has a guru, Sri Vasudevananda Saraswati, who used the title Shankaracharya until 2017. The organization has been the subject of controversy, especially in connection with historical child abuse and the mistreatment of women; it has also been described as a cult, sect or new religious movement. The SES advertises introductory courses in "Practical Philosophy", "Economics with Justice" and other courses including Sanskrit language. The Practical Philosophy course involves a meditative process known as "The Exercise" and discussion of universal themes drawing on the work of European and Indian philosophers such as Plato, Marsilio Ficino, Swami Vivekananda and Adi Shankara, as well as Advaita. Those who continue involvement beyond 4 years mainly study Advaita; they are encouraged to take up meditation and to undertake voluntary work to help with the running of SES, and to attend residential programmes. SES members have founded schools for the education of children in a number of countries. SES is registered as a charity in the UK; worldwide operations register as non-profit organisations in their own countries. SES was founded in London by Labour MP Andrew MacLaren. His successor and son, SES leader Leon MacLaren (1910-1994), a barrister introduced programs on Advaita Vedanta. According to the SES financial report for 2017, it had a total of 3173 enrollments in the UK at the close of that year. As of 2012 it had a total of around 20,000 in up to 80 branches worldwide. Operating under various names, there are branches in America, Canada, Venezuela, Australia, New Zealand, South Africa, Trinidad, Belgium, Cyprus, Greece, Holland, Malta, Spain, Ireland, Hungary, Germany, Israel and Argentina. The head of all of these branches is the SES 'Senior Tutor', MacLaren's successor, Donald Lambie, who is also a barrister. SES course fees are kept low to encourage recruitment; thanks to donations and wills, the organization has substantial properties worldwide, including several mansions.
  • 4.7K
  • 10 Oct 2022
Topic Review
Telugu Script
Telugu script (Telugu: తెలుగు లిపి, romanized: Telugu lipi), an abugida from the Brahmic family of scripts, is used to write the Telugu language, a Dravidian language spoken in the India n states of Andhra Pradesh and Telangana as well as several other neighbouring states. The Telugu script is also widely used for writing Sanskrit texts and to some extent the Gondi language. It gained prominence during the Eastern Chalukyas also known as Vengi Chalukya era. It shares extensive similarities with the Kannada script, as it has evolved from Kadamba and Bhattiprolu scripts of the Brahmi family. In 2008, Telugu language was given the status of Classical Languages of India, this status owes to its rich history and heritage.
  • 4.7K
  • 14 Oct 2022
Topic Review
Challenges to Renewable Energy Transition in China
Climate change and energy issues have become the prominent global challenge and a major concern of China. China’s energy sector, which heavily relies on fossil energy, especially coal, is the largest contributor to China’s carbon emissions. According to the International Energy Agency (IEA), China’s energy consumption accounts for nearly 90% of China’s total CO2 emissions in 2020. The carbon neutrality target poses a huge challenge to China’s energy system, causing energy transition to be the key to the overall decarbonization of China’s economy and society.
  • 4.7K
  • 07 Dec 2022
Topic Review Peer Reviewed
John II Komnenos (1118–1143)
John II Komnenos was the son of Emperor Alexios I Komnenos and Eirene Doukaina, and brother of Princess Anna Komnene, the author of the Alexiad. Born in 1087, he was crowned soon after his fifth birthday as co-emperor with his father, and in 1105, he was married to Piroska Árpád, daughter of King Ladislaus I of Hungary and Adelaide of Rheinfelden. He is principally known for continuing his father’s work of stabilising Byzantium after the crises of the eleventh century. This included major wars of defence and conquest in both the Balkans and Anatolia, and especially a major eastern expedition in 1137–1139. During this campaign, he conquered Cilicia, but he was recalled to defend his borders against the Turks before he could make further conquests in Syria and bring the crusader states under his aegis. He died in a hunting accident just before he returned to Syria, with intentions to go to Jerusalem as well. His best-known iconographic representation is a mosaic of him and his wife in the Great Church of Sophia. Whilst there is also an image of him in a contemporary ornate gospel book, his most common representations are found on his many coin issues and seals. 
  • 4.7K
  • 13 Apr 2022
Topic Review
Muscle Tone Physiology
The simple definition of tone as the resistance to passive stretch is physiologically a complex interlaced network encompassing neural circuits in the brain, spinal cord, and muscle spindle. Disorders of muscle tone can arise from dysfunction in these pathways and manifest as hypertonia or hypotonia. The loss of supraspinal control mechanisms gives rise to hypertonia, resulting in spasticity or rigidity. On the other hand, dystonia and paratonia also manifest as abnormalities of muscle tone, but arise more due to the network dysfunction between the basal ganglia and the thalamo-cerebello-cortical connections. 
  • 4.7K
  • 19 May 2021
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