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Topic Review
Core (Game Theory)
In cooperative game theory, the core is the set of feasible allocations that cannot be improved upon by a subset (a coalition) of the economy's agents. A coalition is said to improve upon or block a feasible allocation if the members of that coalition are better off under another feasible allocation that is identical to the first except that every member of the coalition has a different consumption bundle that is part of an aggregate consumption bundle that can be constructed from publicly available technology and the initial endowments of each consumer in the coalition. An allocation is said to have the core property if there is no coalition that can improve upon it. The core is the set of all feasible allocations with the core property.
  • 3.2K
  • 08 Oct 2022
Topic Review
Forensic Palynology
Forensic palynology is a subdiscipline of palynology (the study of pollen grains, spores, etc.), that aims to prove or disprove a relationship among objects, people, and places that may pertain to both criminal and civil cases. Pollen can reveal where a person or object has been, because regions of the world, countries, and even different parts of a single garden will have a distinctive pollen assemblage. Pollen evidence can also reveal the season in which a particular object picked up the pollen. Palynology is the study of palynomorphs - microscopic structures of both animal and plant origin that are resistant to decay. This includes spermatophyte pollen, as well as spores (fungi, bryophytes, and ferns), dinoflagellates, and various other organic microorganisms - both living and fossilized. There are a variety of ways in which the study of these microscopic, walled particles can be applied to criminal forensics. In areas such as New Zealand, where the demand for this field is high, forensic palynology has been used as evidence in many different case types that range anywhere from non-violent to extremely violent crimes. Pollen has been used to trace activity at mass graves in Bosnia, pinpoint the scene of a crime, and catch a burglar who brushed against a Hypericum bush during a crime. Because pollen has distinct morphology and is relatively indestructible, it is likely to adhere to a variety of surfaces often without notice and has even become a part of ongoing research into forensic bullet coatings.
  • 3.2K
  • 21 Nov 2022
Topic Review
Short Code
Short codes, or short numbers, are short digit sequences, significantly shorter than telephone numbers, that are used to address messages in the Multimedia Messaging System (MMS) and short message service (SMS) systems of mobile network operators. In addition to messaging, they may be used in abbreviated dialing. Short codes are designed to be easier to read and remember than telephone numbers. Short codes are unique to each operator at the technological level. Even so, providers generally have agreements to avoid overlaps. In some countries, such as the United States, some classes of numbers are inter-operator (used by multiple providers or carriers, U.S. inter-operator numbers are called common short codes). Short codes are widely used for value-added services such as charity donations, mobile services, ordering ringtones, and television program voting. Messages sent to a short code can be billed at a higher rate than a standard SMS and may even subscribe a customer to a recurring monthly service that will be added to the customer's mobile phone bill until the user texts, for example, the word "STOP" to terminate the service.
  • 3.2K
  • 10 Nov 2022
Topic Review
Structure and Bonding in Planar Hypercoordinate Carbon Compounds
The term hypercoordination refers to the extent of the coordination of an element by its normal value. In the hypercoordination sphere, the element can achieve planar and/or non-planar molecular shape. Hence, planar hypercoordinate carbon species violate two structural rules: (i) The highest coordination number of carbon is four and (ii) the tetrahedral orientation by the connected elements and/or groups. The unusual planar orientations are mostly stabilized by the electronic interactions of the central atom with the surrounding ligands. Primary knowledge of the planar hypercoordinate chemistry will lead to its forthcoming expansion. Experimental and theoretical interests in planar tetracoordinate carbon (ptC), planar pentacoordinate carbon (ppC), and planar hexacoordinate carbon (phC) are continued. The proposed electronic and mechanical strategies are helpful for the designing of the ptC compounds. Moreover, the 18-valence electron rule can guide the design of new ptC clusters computationally as well as experimentally. However, the counting of 18-valence electrons is not a requisite condition to contain a ptC in a cluster. Furthermore, this ptC idea is expanded to the probability of a greater coordination number of carbon in planar orientations. Unfortunately, until now, there are no such logical approaches to designing ppC, phC, or higher-coordinate carbon molecules/ions. There exist a few global minimum structures of phC clusters identified computationally, but none have been detected experimentally. All planar hypercoordinate carbon species in the global minima may be feasible in the gas phase.
  • 3.2K
  • 26 Dec 2022
Topic Review
Sleep in Declarative Memory Consolidation
There is ample evidence supporting a key role of sleep in memory consolidation. Thalamo-cortical and hippocampal-neocortical interactions allow the reconfiguration of synapses. Oscillatory and molecular changes are involved during sleep in memory consolidation and synaptic rescalling.
  • 3.2K
  • 27 Oct 2020
Topic Review
Effects of Stress Exposure
Stress could be defined as an organism's entire response to environmental demands or strains. Exposure to highly stressful or traumatic events, depending on the stage of life in which stress exposure occurs, could severely affect limbic structures, including the amygdala, and lead to alterations in social and affective behaviors.
  • 3.2K
  • 31 Jan 2021
Topic Review
Application of GIS in Agriculture
GIS technology application in agriculture has gained prominence. The main GIS application areas identified included: crop yield estimation, soil fertility assessment, cropping patterns monitoring, drought assessment, pest and crop disease detection and management, precision agriculture, and fertilizer and weed management. GIS technology has the potential to enhance agriculture sustainability by integrating the spatial dimension of agriculture into agriculture policies. In addition, GIS's potential in promoting evidence-informed decision-making is growing. There is, however, a big gap in GIS application in sub-Saharan Africa. With the growing threat of climate change to agriculture and food security, there is an increased need for the integration of GIS in policy and decision-making in improving agriculture sustainability.
  • 3.2K
  • 09 Sep 2022
Topic Review
Self-Discharge of Batteries
Self-discharge of batteries is a natural, but nevertheless quite unwelcome, phenome­non. Be­cause it is driven in its various forms by the same thermodynamic forces as the discharge dur­ing intended op­era­tion of the device it can only be slowed down by impeding the reaction kinet­ics of its vari­ous steps, i.e. their respective rates of reaction. This approach should be based on a deeper understanding of the various modes and mechanisms of self-discharge, which in turn de­pend on the battery chemistry, its mode of op­eration and environmental conditions. Typical exam­ples from representative battery chemis­tries are presented and observed effects are reviewed. As an outcome of a better understanding ap­proaches to reduce self-discharge are presented.
  • 3.2K
  • 22 Feb 2023
Topic Review
Deacetylation
Acetylation (or in IUPAC nomenclature ethanoylation) describes a reaction that introduces an acetyl functional group into a chemical compound. Deacetylation is the removal of an acetyl group. Acetylation refers to the process of introducing an acetyl group (resulting in an acetoxy group) into a compound, namely the substitution of an acetyl group for an active hydrogen atom. A reaction involving the replacement of the hydrogen atom of a hydroxyl group with an acetyl group (CH3CO) yields a specific ester, the acetate. Acetic anhydride is commonly used as an acetylating agent reacting with free hydroxyl groups. For example, it is used in the synthesis of aspirin, heroin, and THC-O-acetate.
  • 3.2K
  • 29 Nov 2022
Topic Review
Bioactive Compounds from Marine Sponges
Marine sponges are sessile invertebrates that can be found in temperate, polar and tropical regions. They are known to be major contributors of bioactive compounds, which are discovered in and extracted from the marine environment. The compounds extracted from these sponges are known to exhibit various bioactivities, such as antimicrobial, antitumor and general cytotoxicity.
  • 3.2K
  • 25 May 2021
Topic Review
Conjunction
In astronomy, a conjunction occurs when two astronomical objects or spacecraft have either the same right ascension or the same ecliptic longitude, usually as observed from Earth. When two objects always appear close to the ecliptic—such as two planets, the Moon and a planet, or the Sun and a planet—this fact implies an apparent close approach between the objects as seen in the sky. A related word, appulse, is the minimum apparent separation in the sky of two astronomical objects. Conjunctions involve either two objects in the Solar System or one object in the Solar System and a more distant object, such as a star. A conjunction is an apparent phenomenon caused by the observer's perspective: the two objects involved are not actually close to one another in space. Conjunctions between two bright objects close to the ecliptic, such as two bright planets, can be seen with the naked eye. The astronomical symbol for conjunction is (Unicode U+260C ☌). The conjunction symbol is not used in modern astronomy. It continues to be used in astrology.
  • 3.2K
  • 01 Nov 2022
Topic Review
Classification and Biosynthesis of Flavonoids
Flavonoids are mainly found in plant cell vacuoles in the form of C-glycosides or O-glycosides. The basic molecular structure of flavonoids depends upon their basic C6–C3–C6 skeleton. Flavonoids are classified into seven subclasses based on modifications to their basic skeletons; these subclasses include flavones, flavanones, isoflavones, flavonols, chalcones, flavanols, and anthocyanins.
  • 3.2K
  • 04 Jul 2023
Topic Review
Timeline of Lung Cancer
This is a timeline of lung cancer, describing especially major discoveries, advances in treatment and major organizations.
  • 3.2K
  • 22 Nov 2022
Topic Review
Armoured Vehicle Royal Engineers
Armoured Vehicle Royal Engineers (AVRE), also known as Assault Vehicle Royal Engineers is the title given to a series of armoured military engineering vehicles operated by the Royal Engineers (RE) for the purpose of protecting engineers during frontline battlefield operations. In protecting engineers, the vehicles also became a mobile platform for a variety of engineering purposes, mounting large calibre weapons for demolition, carrying engineering stores, mine clearance explosives, a variety of deployable roadways, and modified engineering bridges for gaps that the related Armoured Ramp Carrier ("ARK") vehicles could not overcome.
  • 3.2K
  • 28 Oct 2022
Topic Review
Heat Pump
The Heat Pump (HP) is an environmentally friendly and renewable energy technology that exploits renewable heat energy from the ground, air or water for building or industrial applications by reversing the natural heat flow from a lower to a higher useful temperature. HP technology is commonly classified according to its source, function, type of energy and application. The HPs in cold climate countries are accepted as one of the most outstanding technologies of heating in both residential and commercial buildings, because they provide high seasonal performance factor (SPF), 1.8–3.4 for air source heat pump (ASHP) and 2.5–5.6 for ground source heat pump (GSHP) and water source heat pump (WSHP). However, the spread is large, because of different equipment, design and installation quality as well as maintenance. 
  • 3.2K
  • 28 Jan 2022
Topic Review
Clinical Manifestations of Arthropod Bites
Arthropod blood feeders are vectors of several human pathogenic agents, including viruses (e.g., yellow fever, chikungunya, dengue fever), parasites (e.g., malaria, leishmaniasis, lymphatic filariasis...), or bacteria (e.g., plague...). Besides their role as a vector of pathogens, their biting activities cause a nuisance to humans. We document herein, clinical symptoms associated with the biting of ten clusters of hematophagous arthropods, including mosquitoes, biting midges and sandflies, lice, ticks, tsetse flies, blackflies, horse flies, fleas, triatomine and bed bugs. Within the framework of clinical history and entomo-epidemiological information, we propose a  discriminative key that can be helpful for practicing physicians in identifying hematophagous arthropods biting humans and delivering treatment for the associated clinical disorders.
  • 3.2K
  • 04 Jun 2020
Topic Review
Logistic Handling of Deliveries at an LNG Terminal
LNG is a gas mixture of hydrocarbons in the following proportions: methane 87–99 mol%, ethane 0.1–5.5 mol%, propane 0–4 mol%, butane 0–2.5 mol%, nitrogen 0.02–1 mol%, and traces of sulfur (less than four ppmv) and CO2 (50 ppmv). There has been growing interest in fuel supply chains regarding transport safety and LNG reloading. This is due to the increasing consumption of this gas in the economy to create sustainable transport systems. Poland is in the phase of energy transformation, which increases the demand for this type of alternative fuel. For this reason, the number of logistic operations carried out by Polish sea terminals handling LNG deliveries is increasing.
  • 3.2K
  • 07 May 2022
Topic Review
URL Normalization
URL normalization is the process by which URLs are modified and standardized in a consistent manner. The goal of the normalization process is to transform a URL into a normalized URL so it is possible to determine if two syntactically different URLs may be equivalent. Search engines employ URL normalization in order to assign importance to web pages[clarify] and to reduce indexing of duplicate pages. Web crawlers perform URL normalization in order to avoid crawling the same resource more than once. Web browsers may perform normalization to determine if a link has been visited or to determine if a page has been cached.
  • 3.2K
  • 18 Oct 2022
Topic Review
Hybrid Microgrid System
A novel energy management system for a hybrid microgrid has been developed that uses a new control algorithm termed Inefficient Power Conversion Elimination Algorithm (IPCEA). The proposed algorithm compares the Net Transferable Power (NTP) available at the DC side with the loss rate across the converter. The converter is switched off (or disconnected from the grid and load) if the NTP is less than 20% of the converter rating to avoid low-efficiency power conversion. The solar PV system is connected to the DC bus to supply the DC loads while the AC loads are supplied from the AC source (utility power). An auxiliary battery pack has been integrated to the DC side to feed DC loads during the absence of solar energy. Battery Energy Storage System (BESS) has been deployed to manage energy distribution effectively. Power distribution is managed using a centralized microgrid controller, and the load demand is met accordingly. Thereby, power generated by solar PV can be utilized effectively. Microgrid technology's effectiveness is emphasized by comparative analysis, and the achievements have been discussed in detail and highlighted using a prototype model. The proposed study intends to design a novel switching strategy to incorporate a hybrid microgrid in the distribution system effectively. It comprises the following conventional electrical installation with an intelligent microgrid distribution system: i) To implement a renewable-based IPCEA considering the availability of Net Transferable Power (NTP) at DC bus and the rate of converter loss to minimize low efficient power conversion. ii) To effectively manage battery energy within the DC side of the microgrid to minimize the charge cycle and improve its performance.  iii) To decrease the stress on the utility grid by reducing the rate of power exchange.
  • 3.2K
  • 20 Jun 2022
Topic Review
Taxol Biosynthetic Pathway
Taxol is one of the most effective anticancer drugs in the world that is widely used in the treatment of several cancers. The elucidation of the taxol biosynthetic pathway is the key to solve the problem of taxol supply. So far, the taxol biosynthetic pathway has been reported to require an estimated 20 steps of enzymatic reactions, and most of enzymes involved have been well characterized. In details, the source and formation of the taxane core and the process of the downstream synthetic pathway have been basically depicted, while the modification of the core taxane skeleton has not been fully reported, mainly concerning the developments from diol intermediates to 2-debenzoyltaxane. 
  • 3.2K
  • 01 Jun 2021
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