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Topic Review
Mulberry
Mulberry has acquired a special importance due to its phytochemical composition and its beneficial effects on human health, including antioxidant, anticancer, antidiabetic and immunomodulatory effects. Botanical parts of Morus sp. (fruits, leaves, twigs, roots) are considered rich source of nutrients and secondary metabolites. Various mulberry-based foods have been developed and marketed around the world.
  • 2.9K
  • 24 Feb 2022
Topic Review
Explicit Formulae (L-function)
In mathematics, the explicit formulae for L-functions are relations between sums over the complex number zeroes of an L-function and sums over prime powers, introduced by (Riemann 1859) for the Riemann zeta function. Such explicit formulae have been applied also to questions on bounding the discriminant of an algebraic number field, and the conductor of a number field.
  • 2.9K
  • 01 Nov 2022
Topic Review
Gas/Oil-Relative Permeabilities
Thermal recovery processes for heavy oil exploitation involve three-phase flow at elevated temperatures. The mathematical modeling of such processes necessitates the account of changes in the rock–fluid system’s flow behavior as the temperature rises. To this end, numerous studies on effects of the temperature on relative permeabilities have been reported in the literature. Compared to studies on the temperature effects on oil/water-relative permeabilities, studies (and hence, data) on gas/oil-relative permeabilities are limited. However, the role of temperature on both gas/oil and oil/water-relative permeabilities has been a topic of much discussion, contradiction and debate. The jury is still out, without a consensus, with several contradictory hypotheses, even for the limited number of studies on gas/oil-relative permeabilities. This study presents a critical analysis of studies on gas/oil-relative permeabilities as reported in the literature, and puts forward an undeniable argument that the temperature does indeed impact gas/oil-relative permeabilities and the other fluid–fluid properties contributing to flow in the reservoir, particularly in a thermal recovery process. It further concludes that such thermal effects on relative permeabilities must be accounted for, properly and adequately, in reservoir simulation studies using numerical models. The paper presents a review of most cited studies since the 1940s and identifies the possible primary causes that contribute to contradictory results among them, such as differences in experimental methodologies, experimental difficulties in flow data acquisition, impact of flow instabilities during flooding, and the differences in the specific impact of temperature on different rock–fluid systems. We first examined the experimental techniques used in measurements of oil/gas-relative permeabilities and identified the challenges involved in obtaining reliable results. Then, the effect of temperature on other rock–fluid properties that may affect the relative permeability was examined. Finally, we assessed the effect of temperature on parameters that characterized the two-phase oil/gas-relative permeability data, including the irreducible water saturation, residual oil saturation and critical gas saturation. Through this critical review of the existing literature on the effect of temperature on gas/oil-relative permeabilities, we conclude that it is an important area that suffers profoundly from a lack of a comprehensive understanding of the degree and extent of how the temperature affects relative permeabilities in thermal recovery processes, and therefore, it is an area that needs further focused research to address various contradictory hypotheses and to describe the flow in the reservoir more reliably.
  • 2.9K
  • 14 Jul 2020
Topic Review
The Biology of Coral
Coral reefs are portrayed as tropical underwater forests, profusely rich in biodiversity and has immense ecological and economical importance. Apart from other marine calcifying organisms, scleractinian corals are the major biogenic contributor of complex bicarbonate structures. Corals are built from a collective group of tiny transparent organisms known as coral polyps. The increasing impact of natural and anthropogenic factors such as variation in temperature, salinity, cyclones, pollution and so forth have exert direct or direct effects on the coral reef, engendering the phenomenon of coral bleaching with severe outcomes. Coral microbiome comprises of diverse microorganisms including symbiotic algae, which play a determining role in coral physiology, immunity and responsiveness. Further, corals are equipped with sophisticate chemical and biological warfare that is used to their advantage in unfavorable conditions. 
  • 2.9K
  • 18 Jul 2022
Topic Review
Resistance in Powdery Mildew Fungi
Powdery mildew fungi (Erysiphales) are among the most common and important plant fungal pathogens. These fungi are obligate biotrophic parasites that attack nearly 10,000 species of angiosperms, including major crops, such as cereals and grapes. Although cultural and biological practices may reduce the risk of infection by powdery mildew, they do not provide sufficient protection. Therefore, in practice, chemical control, including the use of fungicides from multiple chemical groups, is the most effective tool for managing powdery mildew. Unfortunately, the risk of resistance development is high because typical spray programs include multiple applications per season. In addition, some of the most economically destructive species of powdery mildew fungi are considered to be high-risk pathogens and are able to develop resistance to several chemical classes within a few years. This situation has decreased the efficacy of the major fungicide classes, such as sterol demethylation inhibitors, quinone outside inhibitors and succinate dehydrogenase inhibitors, that are employed against powdery mildews.
  • 2.9K
  • 25 Sep 2020
Topic Review
Panama Papers (Europe)
The Panama Papers are 11.5 million leaked documents that detail financial and attorney–client information for more than 214,488 offshore entities. The documents, some dating back to the 1970s, were created by, and taken from, Panamanian law firm and corporate service provider Mossack Fonseca, and were leaked in 2015 by an anonymous source. This page details related allegations, reactions, and investigations, in Europe.
  • 2.9K
  • 04 Nov 2022
Topic Review
Information Exactly Defined
This review focuses the exact and global definition of information (for unambiguous interpretation as mathematical object) and its digital application. New uniformly defined "domain vectors" (DVs), with structure "UL plus number sequence", are proposed. The "UL" is an efficient global pointer to the uniform online definition of the (after the UL) following number sequence. DVs are globally exactly defined, identified, interoperable, comparable, and (language independently) searchable by criteria which users can define online. The introduction of a compact DV data structure may substantially improve the digital representation of information.
  • 2.9K
  • 11 Apr 2021
Topic Review
Triceratops Obtusus
Triceratops (/traɪˈsɛrəˌtɒps/ trahy-ser-uh-tops; lit. three-horned face) is a genus of herbivorous chasmosaurine ceratopsid dinosaur that first appeared during the late Maastrichtian stage of the Late Cretaceous period, about 68 million years ago in what is now North America. It is one of the last-known non-avian dinosaur genera, and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. The name Triceratops, which literally means 'three-horned face', is derived from the Greek words trí- (τρί-) meaning 'three', kéras (κέρας) meaning 'horn', and ṓps (ὤψ) meaning 'face'. Bearing a large bony frill, three horns on the skull, and a large four-legged body, exhibiting convergent evolution with rhinoceroses and bovines, Triceratops is one of the most recognizable of all dinosaurs and the most well-known ceratopsid. It was also one of the largest, up to 8–9 metres (26–30 ft) long and 5–9 metric tons (5.5–9.9 short tons) in body mass. It shared the landscape with and was most likely preyed upon by Tyrannosaurus, though it is less certain that two adults did battle in the fanciful manner often depicted in museum displays and popular images. The functions of the frills and three distinctive facial horns on its head have long inspired debate. Traditionally, these have been viewed as defensive weapons against predators. More recent interpretations find it probable that these features were primarily used in species identification, courtship, and dominance display, much like the antlers and horns of modern ungulates. Triceratops was traditionally placed within the "short-frilled" ceratopsids, but modern cladistic studies show it to be a member of the Chasmosaurinae which usually have long frills. Two species, T. horridus and T. prorsus, are considered valid today, from the seventeen species that have ever been named. Research published in 2010 concluded that the contemporaneous Torosaurus, a ceratopsid long regarded as a separate genus, represents Triceratops in its mature form. This view has been disputed; further data is needed to settle the debate. Triceratops has been documented by numerous remains collected since the genus was first described in 1889 by American paleontologist Othniel Charles Marsh. Specimens representing life stages from hatchling to adult have been found. As the archetypal ceratopsid, Triceratops is one of the most popular dinosaurs, and has been featured in film, postal stamps, and many other types of media.
  • 2.9K
  • 17 Nov 2022
Topic Review
Adipose-Derived Stem Cells
Adipose-derived stem cells (ASCs) are a subpopulation of mesenchymal stem cells. Compared to bone marrow-derived stem cells, they can be harvested with minimal invasiveness. ASCs can be easily expanded and were shown to be able to differentiate into several clinically relevant cell types. Therefore, this cell type represents a promising component in various tissue engineering and medical approaches (e.g., cell therapy).
  • 2.9K
  • 22 Feb 2023
Topic Review
Cocona Fruits from the Peruvian Amazon
Cocona fruits are a popular food and medicinal fruit used mainly in the Amazon and several countries of South America for the preparation of several food products such as drinks, jams and milk shakes. In this study five ecotypes of cocona native to Peru have been studied regarding their nutritional and antioxidants values plus antihyperlipidemic activities.
  • 2.9K
  • 29 Mar 2022
Topic Review
Pearl Millet (Pennisetum glaucum) for Diabetes Mellitus
Diabetes mellitus has become a troublesome and increasingly widespread condition. Treatment strategies for diabetes prevention in high-risk as well as in affected individuals are largely attributed to improvements in lifestyle and dietary control. Therefore, it is important to understand the nutritional factors to be used in dietary intervention.
  • 2.9K
  • 09 Aug 2022
Topic Review
Heterogeneous Electroreduction of CO2 on Copper-Based Catalysts
Facing greenhouse effects and the rapid exhaustion of fossil fuel, CO2 electrochemical reduction presents a promising method of environmental protection and energy transformation. Low onset potential, large current density, high faradaic efficiency (FE), and long-time stability are required for industrial production, due to economic costs and energy consumption. Copper is one of the few metals that can reduce CO2 to hydrocarbons and alcohols with decent efficiency, and copper-based catalysts have received much attention. The uniqueness of Cu as a CO2RR electrocatalyst is explained by the fact that it is the only metal that has negative adsorption energy for *CO and positive adsorption energy for *H.
  • 2.9K
  • 18 Aug 2022
Topic Review
Wonders of the World
Various lists of the Wonders of the World have been compiled from antiquity to the present day, to catalogue the world's most spectacular natural wonders and manmade structures. The Seven Wonders of the Ancient World is the first known list of the most remarkable creations of classical antiquity; it was based on guidebooks popular among Ancient Greece sightseers and only includes works located around the Mediterranean rim and in Mesopotamia. The number seven was chosen because the Greeks believed it represented perfection and plenty, and because it was the number of the five planets known anciently, plus the sun and moon. Many similar lists have been made.
  • 2.9K
  • 23 Nov 2022
Topic Review
Sonic Boom Prediction and Minimization
NASA describes the sonic boom as “thunder-like noise a person on the ground hears when an aircraft […] flies overhead faster than the speed of sound”. Sonic boom results from the coalescence of the shock waves generated by an aircraft flying supersonicly trough their propagation into the atmosphere to the ground.
  • 2.9K
  • 08 Nov 2023
Topic Review
Auction
An auction is usually a process of buying and selling goods or services by offering them up for bids, taking bids, and then selling the item to the highest bidder or buying the item from the lowest bidder. Some exceptions to this definition exist and are described in the section about different types. The branch of economic theory dealing with auction types and participants' behavior in auctions is called auction theory. The open ascending price auction is arguably the most common form of auction in use throughout history. Participants bid openly against one another, with each subsequent bid required to be higher than the previous bid. An auctioneer may announce prices, bidders may call out their bids themselves or have a proxy call out a bid on their behalf, or bids may be submitted electronically with the highest current bid publicly displayed. Auctions were and are applied for trade in diverse contexts. These contexts are antiques, paintings, rare collectibles, expensive wines, commodities, livestock, radio spectrum, used cars, online advertising, even emission trading and many more.
  • 2.9K
  • 08 Nov 2022
Topic Review
Recent Advances in A3 Coupling with Metal Salts
Recent advances in the metal salt catalysed multicomponent reaction of aldehydes, amines, and alkynes, known as A3 coupling, which yields propargylamines, a valuable organic scaffold.
  • 2.9K
  • 04 Jul 2022
Topic Review
Thia-Michael Reaction
While the Michael addition has been employed for more than 130 years for the synthesis of a vast diversity of compounds, the reversibility of this reaction when heteronucleophiles are involved has been generally less considered. First applied to medicinal chemistry, the reversible character of the hetero-Michael reactions has been explored for the synthesis of Covalent Adaptable Networks (CANs), in particular the thia-Michael reaction and more recently the aza-Michael reaction. In these cross-linked networks, exchange reactions take place between two Michael adducts by successive dissociation and association steps. In order to understand and precisely control the exchange in these CANs, it is necessary to get an insight into the critical parameters influencing the Michael addition and the dissociation rates of Michael adducts by reconsidering previous studies on these matters. 
  • 2.9K
  • 28 Nov 2022
Topic Review
LiDAR-Derived DEM in Flood Applications
Flood occurrence is increasing due to escalated urbanization and extreme climate change; hence, various studies on this issue and methods of flood monitoring and mapping are also increasing to reduce the severe impacts of flood disasters. The advancement of current technologies such as light detection and ranging (LiDAR) systems facilitated and improved flood applications. Since the conventional methods cannot produce high-resolution digital elevation model (DEM) data, which results in low accuracy of flood simulation results, LiDAR data are extensively used as an alternative. This review aims to study the potential and the applications relevant to flood studies from a LiDAR-derived DEM perspective. It also provides insight into the operating principles of different LiDAR systems, system components, and advantages and disadvantages of each system. Furthermore, the challenges and future perspectives regarding DEM LiDAR data for flood mapping and assessment are also discussed. This study demonstrates that LiDAR-derived data are useful in flood risk management, especially in the future assessment of flood-related problems.  
  • 2.9K
  • 04 Aug 2020
Topic Review
Optical Accelerometers
Optical accelerometers are high-precision inertial sensors that use optical measurement technology to achieve high-precision and electromagnetic interference-resistant acceleration measurements. With the intensive research and development of optical accelerometers in recent years, their applications in inertial navigation, structural health monitoring, precision vibration isolation systems, wind turbine fault monitoring, earthquake monitoring, and other low-frequency vibration detection have flourished. Optical accelerometers have various schemes; however, their characteristics vary considerably due to different optical modulation schemes. This study aims to address the lack of systematic evaluation of currently available low-frequency optical accelerometers. Optical accelerometers can be classified into four categories in accordance with their optical modulation schemes: optical path-, optical intensity-, optical phase-, and optical wave-length-modulated accelerometers. 
  • 2.9K
  • 16 Jun 2022
Topic Review
Exposure Routes and Health Risks Associated with Pesticides
There are four main pesticide application methods, including hydraulic spraying, backpack spraying, basal trunk spraying, and aerial spraying. Pesticide application methods are mainly selected by considering the habits of target pests, the characteristics of target sites, and the properties of pesticides. Humans are directly exposed to pesticides in occupational, agricultural, and household activities and are indirectly exposed to pesticides via environmental media, including air, water, soil, and food. Human exposure to pesticides occurs mainly through dermal, oral, and respiratory routes. People who are directly and/or indirectly exposed to pesticides may contract acute toxicity effects and chronic diseases. Although no segment of the general population is completely protected against exposure to pesticides and their potentially serious health effects, a disproportionate burden is shouldered by people in developing countries. Both deterministic and probabilistic human health risk assessments have their advantages and disadvantages and both types of methods should be comprehensively implemented in research on exposure and human health risk assessment. Equipment for appropriate pesticide application is important for application efficiency to minimize the loss of spray solution as well as reduce pesticide residuals in the environment and adverse human health effects due to over-spraying and residues. Policymakers should implement various useful measures, such as integrated pest management (IPM) laws that prohibit the use of pesticides with high risks and the development of a national implementation plan (NIP) to reduce the adverse effects of pesticides on the environment and on human health. 
  • 2.9K
  • 30 Jul 2022
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