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Topic Review
Organic Matter Sources in Lake Sediments
Sedimentary organic matter is an important component of the metabolism of a lake’s ecosystem, and it is generally derived from both the watershed and the primary productivity of a lake. Understanding the sources of organic matter in lakes and lake trophic status is important when evaluating the quality of lake ecosystems.
  • 4.0K
  • 01 Mar 2023
Topic Review
Pomegranate Juice for CYP3A4- and CYP2C9-Mediated Drugs Metabolism
The Punica granatum L. (pomegranate) fruit juice contains large amounts of polyphenols, mainly tannins such as ellagitannin, punicalagin, and punicalin, and flavonoids such as anthocyanins, flavan-3-ols, and flavonols. These constituents have high antioxidant, anti-inflammatory, anti-diabetic, anti-obesity, and anticancer activities. Because of these activities, many patients may consume pomegranate juice (PJ) with or without their doctor’s knowledge. This may raise any significant medication errors or benefits because of food-drug interactions that modulate the drug’s pharmacokinetics or pharmacodynamics. 
  • 4.0K
  • 18 May 2023
Topic Review
Serratiopeptidase
Microbial products have been used for the treatment of different diseases for many centuries. The serratiopeptidase enzyme provides a new hope for COVID-19-infected patients. Anti-inflammatory drugs are easy to obtain at minimal expenditure from microbial sources. Serratia sp. is identified as one of the most efficient bacteria produced from serratiopeptidase. Screening for new and efficient bacterial strains from different sources has been of interest. Serratiopeptidase remains the most well-known anti-inflammatory drug of choice. Serratiopeptidase is a cheaper and safer anti-inflammatory drug alternative to NSAIDs.
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  • 01 Feb 2023
Topic Review
Battery Swapping Stations for Electric Vehicles
Battery Swapping Stations (BSS), refers to the rapid recovery of electric vehicle energy by replacing batteries when the electric vehicle energy is about to run out.  Figure 1 shows the structure of BSS. The Electric vehicle users only own cars and rent batteries from service operators, thus greatly reducing the purchase cost of electric vehicles and solving the problem of long charging times.
  • 4.0K
  • 19 Apr 2022
Topic Review
Semiconductor Gas Sensors
Semiconductor materials include metal oxides, conducting polymers, carbon nanotubes, and 2D materials. Metal oxides are most often the first choice due to their ease of fabrication, low cost, high sensitivity, and stability. Some of their disadvantages are low selectivity and high operating temperature. Conducting polymers have the advantage of a low operating temperature and can detect many organic vapors. They are flexible but affected by humidity. Carbon nanotubes are chemically and mechanically stable and are sensitive towards NO and NH3, but need dopants or modifications to sense other gases. Graphene, transition metal chalcogenides, boron nitride, transition metal carbides/nitrides, metal organic frameworks, and metal oxide nanosheets as 2D materials represent gas-sensing materials of the future, especially in medical devices, such as breath sensing.
  • 4.0K
  • 10 Dec 2020
Topic Review
AI Art
Artists have been working with artificial intelligence (AI) since the 1970s. They comprised a minuscule enclave within the early computer art community throughout the 1970s and 1980s and were largely unnoticed by the mainstream artworld and broader public. In the 1990s and 2000s, more artists got involved with AI and produced installations that question the meaning of agency, creativity, and expression. Since the 2000s, AI art diversified into generative and interactive approaches that involved statistical methods, natural language processing, pattern recognition, and computer vision algorithms. The increasing affordance of multilayered machine learning architectures, as well as the raising socio-political impact of AI, have facilitated the further expansion of AI art in the second half of the 2010s. The topics, methodologies, presentational formats, and implications of contemporary AI art are closely related to, and affected by, AI science research, development, and commercial application. The poetic scope of AI art is primarily informed by the various phenomenological aspects of sub-symbolic machine learning. It comprises creative strategies that explore the epistemological boundaries and artifacts of AI architectures; sample the latent space of neural networks; aestheticize the AI data renderings; and critique the conceptual, existential, or socio-political consequences of corporate AI; a few works criticize AI art itself. These strategies unfold in disparate practices ranging from popular and spectacular to tactical and experimental. The existing taxonomies or categorizations of AI art should be considered as provisory because of the creative dynamics and transdisciplinary character of the field. Similar to other computational art disciplines, AI art has had an ambivalent relationship with the mainstream artworld, marked by selective marginalization and occasional exploitation.
  • 4.0K
  • 27 Jan 2022
Topic Review
Void Coefficient
In nuclear engineering, the void coefficient (more properly called void coefficient of reactivity) is a number that can be used to estimate how much the reactivity of a nuclear reactor changes as voids (typically steam bubbles) form in the reactor moderator or coolant. Net reactivity in a reactor is the sum total of all these contributions, of which the void coefficient is but one. Reactors in which either the moderator or the coolant is a liquid typically will have a void coefficient value that is either negative (if the reactor is under-moderated) or positive (if the reactor is over-moderated). Reactors in which neither the moderator nor the coolant is a liquid (e.g., a graphite-moderated, gas-cooled reactor) will have a void coefficient value equal to zero. It is unclear how the definition of 'void' coefficient applies to reactors in which the moderator/coolant is neither liquid nor gas (supercritical water reactor).
  • 4.0K
  • 22 Nov 2022
Topic Review
Social Stratification
Social stratification is the hierarchical arrangement of individuals or groups in a society based on various attributes such as wealth, social status, and power. This system categorizes people into different strata, influencing their access to resources, opportunities, and privileges. Social stratification is a pervasive phenomenon that shapes social interactions and plays a crucial role in determining an individual's life chances and societal positioning.
  • 4.0K
  • 25 Jan 2024
Topic Review
Aluminum-Fuel-Based Energy Conversion Systems
Metallic aluminum is widely used in propellants, energy-containing materials, and batteries due to its high energy density. In addition to burning in the air, aluminum can react with water to generate hydrogen. Aluminum is carbon-free and the solid-phase products can be recycled easily after the reaction. Micron aluminum powder is stable in the air and enables global trade. Aluminum metal is considered to be a viable recyclable carrier for clean energy.
  • 4.0K
  • 05 Jan 2023
Topic Review
Legal Norms
Legal norms are binding rules, or norms, of conduct that organisations of sovereign power promulgate and enforce in order to regulate social relations. Legal norms determine the rights and duties of individuals who are the subjects of legal relations within the governing jurisdiction at a given point in time. Competent state authority issue and publish basic aspects of legal norms through a collection of laws that individuals under that government must abide to, which is further guaranteed by state coercion. There are two categories of legal norms: normativity, that regulates the conduct of people, and generality, which are binding for the indefinite number of people and cases. Diplomatic and legislative immunity refers to instances where legal norms are constructed to be targeted towards a minority and are specifically only binding for them, such as soldiers and public officials. In a legal sense, retro-activity refers to a law that impairs or invalidates the vested rights of an individual acquired under existing laws by creating new obligations to considerations that have been pre-established. Legal norms can either classify under true retro-activity, where norms influence the legal relations that have existed before its effect, or pseudo retro-activity, referring to how the validity of old legal relations can be influenced by derogated norms. Legal norms become validated from the moment it is published as part of legal order and become in effect from the moment it binds the subjects of the law. The Latin phrase, ‘vacatio legis’ refers to the period of time between a legal norm’s validity and effect. As the validity of a legal norm is limited from the moment of its adoption by legal institutions, a lapse of time can cause its termination. Legal norms can either be terminated by explicit derogation by the competent state authority, or through automatic derogation whereby the authoritative organisation adopts a new normative act that regulates the same relations, effectively replacing the old one.
  • 4.0K
  • 19 Oct 2022
Topic Review
List of Aircraft in the Smithsonian Institution
The List of aircraft in the Smithsonian Institution includes aircraft exhibited in the Smithsonian Institution's National Air and Space Museum, Steven F. Udvar-Hazy Center, and the Paul E. Garber Preservation, Restoration, and Storage Facility. The Smithsonian Institution's collection of aircraft and spacecraft is the largest on display in the world.
  • 4.0K
  • 21 Oct 2022
Topic Review
Polyamory
Polyamory (from grc πολλοί (polloí) 'many', and la amor 'love') is the practice of, or desire for, romantic relationships with more than one partner at the same time, with the informed consent of all partners involved. People who identify as polyamorous may believe in open relationships with a conscious management of jealousy and reject the view that sexual and relational exclusivity are prerequisite for deep, committed, long-term, loving relationships. Others prefer to restrict their sexual activity to only members of the group, a closed polyamorous relationship that is usually referred to as polyfidelity. Polyamory has come to be an umbrella term for various forms of non-monogamous, multi-partner relationships, or non-exclusive sexual or romantic relationships. Its usage reflects the choices and philosophies of the individuals involved, but with recurring themes or values, such as love, intimacy, honesty, integrity, equality, communication, and commitment. It can sometimes be distinguished from some other forms of ethical non-monogamy in that the relationships involved are loving intimate relationships, as opposed to purely sexual relationships.
  • 4.0K
  • 17 Nov 2022
Topic Review
War Bride
War brides are women who married military personnel from other countries in times of war or during military occupations, a practice that occurred in great frequency during World War I and World War II. Among the largest and best documented examples of this were the marriages between American servicemen and German women which took place after World War II. By 1949, over 20,000 German war brides had emigrated to the United States. Furthermore, it is estimated that there are "... 15,000 Australian women who married American servicemen based in Australia during World War II and moved to the US to be with their husbands". Allied servicemen also married many women in other countries where they were stationed at the end of the war, including France , Italy, Luxembourg, the Philippines , Japan and China . This also occurred in Korea and Vietnam with the later wars in those countries involving U.S. troops and other anti-communist soldiers. As many as 70,000 GI war brides left the United Kingdom, 150,000 to 200,000 hailed from continental Europe, 15,500 from Australia and 1,500 from New Zealand, between the years 1942 and 1952. The reasons for women marrying foreign soldiers and leaving their homelands vary. Particularly after World War II, many women in devastated European and Asian countries saw marriage as a means of escaping their devastated countries.
  • 4.0K
  • 14 Oct 2022
Topic Review
Carbon Quantum Dots and Graphene Quantum Dots
Carbon quantum dots (CQDs) are small carbon NPs with a size less than 10 nm having excellent conductivity, chemical stability, environmental friendliness, high photostability, broadband optical absorption, low toxicity, photobleaching resistance, high surface area, and ease of modification. Graphene quantum dots (GQDs) are two-dimensional nanocrystals composed of small graphene particles with lateral diameters less than 100 nm. 
  • 4.0K
  • 12 Oct 2022
Topic Review
Polymer Solar Cells Based on PEDOT:PSS Electrodes
Solution-processed polymer solar cells (PSCs) have advantages of low cost, solution processability, light weight, and excellent flexibility. Recent progress in materials synthesis and devices engineering has boosted the power conversion efficiency (PCE) of single-junction PSCs over 17%. Poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) is one of the most promising candidates for electrodes due to its high conductivity (>4000 S/cm), excellent transmittance (>90%), intrinsically high work function (WF > 5.0 eV), and aqueous solution processability. To date, a great number of single-junction PSCs based on PEDOT:PSS electrodes have realized a PCE over 12%.
  • 4.0K
  • 10 Dec 2021
Topic Review Peer Reviewed
Numerical Solution of Desiccation Cracks in Clayey Soils
This entry presents the theoretical fundamentals, the mathematical formulation, and the numerical solution for the problem of desiccation cracks in clayey soils. The formulation uses two stress state variables (total stress and suction) and results in a non-symmetric and nonlinear system of transient partial differential equations. A release node algorithm technique is proposed to simulate cracking, and the strategy to implement it in the hydromechanical framework is explained in detail. This general framework was validated with experimental results, and several numerical examples were published at international conferences and in journal papers.
  • 4.0K
  • 25 May 2022
Biography
Venkatraman Ramakrishnan
Venkatraman "Venki" Ramakrishnan (born 1952)[1] is an American and British structural biologist of Indian origin. He was elected President of the Royal Society in November 2015; Presidents serve for five years.[2] In 2009 he shared the Nobel Prize in Chemistry with Thomas A. Steitz and Ada Yonath, "for studies of the structure and function of the ribosome".[3][4][5][6][7] Since 1999, he has wor
  • 4.0K
  • 21 Nov 2022
Topic Review
List of Railway Electrification Systems
This is a list of the power supply systems that are, or have been, used for tramway and railway electrification systems. Note that the voltages are nominal and vary depending on load and distance from the substation. Many modern trams and trains use on-board solid-state electronics to convert these supplies to run three-phase AC induction motors. Tram electrification systems are listed here.
  • 4.0K
  • 27 Nov 2022
Topic Review
Superoxide Radical Anion O2•−
Classically, superoxide anion O2•− and reactive oxygen species ROS play a dual role. At the physiological balance level, they are a by-product of O2 reduction, necessary for cell signalling, and at the pathological level they are considered harmful, as they can induce disease and apoptosis, necrosis, ferroptosis, pyroptosis and autophagic cell death.
  • 4.0K
  • 31 Jan 2023
Topic Review Peer Reviewed
T’amar Bagrationi (1184–1210)
T’amar Bagrationi, Queen of Georgia (1184–1210). T’amar Bagrationi was the ninth monarch from the royal house of Bagrationis who ruled over the united Georgian Kingdom. She reigned as a co-monarch alongside her father, Giorgi III, from 1178, assuming full authority in 1184. During her reign, dynastic legitimacy necessitated the appearance of the monumental royal portraits displaying the monarch with immediate predecessors and heirs. T’amar’s gender required introduction of meticulous visual language that would re-gender her with all signs of a male ruler and justify her status and sole right to rule. This notion was embodied in her portraits that were carefully incorporated in the overall programmes of the churches. T’amar’s five monumental depictions survive where she is identified in inscriptions; two other monumental images are presumed to depict her. Of all the depictions, only one can be determined to have been commissioned directly by her. T’amar’s imagery relies on Byzantine elements and adheres to established Georgian models for the local royal portraiture; however, it also adopted sophisticated visual means that was aptly used for manifesting royal power and manipulating authority over the nobility. 
  • 4.0K
  • 18 Aug 2022
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