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Topic Review
A discrete quantum momentum operator
We introduce finite-differences derivatives intended to be exact when applied to the real exponential function. We want to recover the known results of continuous calculus with our finite differences derivatives but in a discrete form. The purpose of this work is to have a discrete momentum operator suitable for use as an operator in discrete quantum mechanics theory.
  • 3.0K
  • 24 Aug 2021
Topic Review
Non-Mechanical Hybrid Hydrogen Compression
Non-mechanical hybrid hydrogen compressors consists of a first electrochemical compression stage followed by a second one based on the adsorption-desorption of hydrogen on microporous materials. They allow compressing hydrogen up to 70 MPa. Non-mechanical hybrid hydrogen compressors can be a valid alternative to the mechanical compressors. 
  • 3.0K
  • 29 Jun 2020
Topic Review
Antimicrobial Blue Light
Blue light primarily exhibits antimicrobial activity through the activation of endogenous photosensitizers, which leads to the formation of reactive oxygen species that attack components of bacterial cells, such as cell wall, cell membrane and genome. Current data show that blue light is innocuous on the skin, but may inflict photo-damage to the eyes. While complete resistance to blue light has not been reported, isolated evidence suggests that bacterial tolerance to blue light may occur over time, especially through gene mutations, although at a slower rate than antibiotic resistance. Future studies can aim at characterizing the amount and type of intracellular photosensitizers across bacterial species and at assessing the oxygen-independent mechanism of blue light.
  • 3.0K
  • 11 Jan 2021
Topic Review
LC-MS Methods for Mycotoxins Detection in Food Products
Mycotoxins are a group of natural compounds produced under a wide range of climatic conditions by filamentous fungi mainly belonging to Aspergillus, Penicillium, Fusarium, Claviceps and Alternaria species. These toxins can contaminate various agricultural commodities (cereals, dried fruits, nuts, spices and coffee being the most frequently contaminated ones) either before harvest or under postharvest conditions, thus posing a risk to human and animal health due to their toxic effects.
  • 3.0K
  • 15 Jun 2022
Topic Review
Subject
A subject is a being who has a unique consciousness and/or unique personal experiences, or an entity that has a relationship with another entity that exists outside itself (called an "object"). A subject is an observer and an object is a thing observed. This concept is especially important in Continental philosophy, where 'the subject' is a central term in debates over the nature of the self. The nature of the subject is also central in debates over the nature of subjective experience within the Anglo-American tradition of analytical philosophy. The sharp distinction between subject and object corresponds to the distinction, in the philosophy of René Descartes, between thought and extension. Descartes believed that thought (subjectivity) was the essence of the mind, and that extension (the occupation of space) was the essence of matter.
  • 3.0K
  • 18 Nov 2022
Topic Review
Drug–Food Interactions of DOACs
In recent years direct oral anticoagulants (DOACs) have become the anticoagulant treatment of choice. DOACs were initially considered drugs with no significant food interactions; however, clinical observations from daily practice have proved otherwise as interactions with food ingredients have been reported. Food, dietary supplements or herbs may contain substances that, when administered concomitantly with DOACs, can potentially affect the plasma concentration of the drugs. 
  • 3.0K
  • 27 Aug 2021
Topic Review
Fintech and Financial Risks
Fintech is the combination of the words of finance and technology. It is literally understood as the application of technology in the financial field. As the financial innovation brought by technology, Fintech can change traditional financial markets, financial institutions and financial services, and create emerging business models, applications, processes, and products.
  • 3.0K
  • 05 Aug 2022
Topic Review
Trust (Emotion)
In a social context, trust has several connotations. Definitions of trust typically refer to a situation characterized by the following aspects: One party (trustor) is willing to rely on the actions of another party (trustee); the situation is directed to the future. In addition, the trustor (voluntarily or forcedly) abandons control over the actions performed by the trustee. As a consequence, the trustor is uncertain about the outcome of the other's actions; they can only develop and evaluate expectations. The uncertainty involves the risk of failure or harm to the trustor if the trustee will not behave as desired. Trust can be attributed to relationships between people. It can be demonstrated that humans have a natural disposition to trust and to judge trustworthiness that can be traced to the neurobiological structure and activity of a human brain. Some studies indicate that trust can be altered e.g. by the application of oxytocin. When it comes to the relationship between people and technology, the attribution of trust is a matter of dispute. The intentional stance demonstrates that trust can be validly attributed to human relationships with complex technologies. However, rational reflection leads to the rejection of an ability to trust technological artefacts. One of the key current challenges in the social sciences is to re-think how the rapid progress of technology has impacted constructs such as trust. This is specifically true for information technology that dramatically alters causation in social systems. In the social sciences, the subtleties of trust are a subject of ongoing research. In sociology and psychology the degree to which one party trusts another is a measure of belief in the honesty, fairness, or benevolence of another party. The term "confidence" is more appropriate for a belief in the competence of the other party. A failure in trust may be forgiven more easily if it is interpreted as a failure of competence rather than a lack of benevolence or honesty. In economics, trust is often conceptualized as reliability in transactions. In all cases trust is a heuristic decision rule, allowing the human to deal with complexities that would require unrealistic effort in rational reasoning. In religion, trust is the faith and hope in good God who forgives everything and gives everlasting happiness.
  • 3.0K
  • 08 Nov 2022
Topic Review
Selenography
Selenography is the study of the surface and physical features of the Moon. Historically, the principal concern of selenographists was the mapping and naming of the lunar maria, craters, mountain ranges, and other various features. This task was largely finished when high resolution images of the near and far sides of the Moon were obtained by orbiting spacecraft during the early space era. Nevertheless, some regions of the Moon remain poorly imaged (especially near the poles) and the exact locations of many features (like crater depths) are uncertain by several kilometers. Today, selenography is considered to be a subdiscipline of selenology, which itself is most often referred to as simply "lunar science." The word selenography is derived from the Greek lunar deity Σελήνη Selene and γράφω graphō, "I write".
  • 3.0K
  • 11 Nov 2022
Topic Review
Pheomelanin
Pheomelanin is a natural yellow-reddish sulfur-containing pigment derived from tyrosinase-catalyzed oxidation of tyrosine in presence of cysteine. It is one of the existing forms of the natural pigment melanin, which is present in the skin in two forms: eumelanin and pheomelanin. Generally, the formation of melanin pigments is a protective response against the damaging effects of UV radiation in skin.
  • 3.0K
  • 20 Jan 2022
Topic Review
Living Anionic Polymerization
Living anionic polymerization is a living polymerization technique involving an anionic propagating species. Living anionic polymerization was demonstrated by Szwarc and co workers in 1956. Their initial work was based on the polymerization of styrene and dienes. One of the remarkable features of living anionic polymerization is that the mechanism involves no formal termination step. In the absence of impurities, the carbanion would still be active and capable of adding another monomer. The chains will remain active indefinitely unless there is inadvertent or deliberate termination or chain transfer. This gave rise to two important consequences: The following experimental criteria have been proposed as a tool for identifying a system as living polymerization system. However, in practice, even in the absence of terminating agents, the concentration of the living anions will reduce with time due to a decay mechanism termed as spontaneous termination.
  • 3.0K
  • 31 Oct 2022
Topic Review
Nitric Oxide Synthase
Nitric oxide synthase (NOS) plays important roles within the cardiovascular system in physiological states as well as in pathophysiologic and specific cardiovascular (CV) disease states, such as hypertension (HTN), arteriosclerosis, and cerebrovascular accidents.
  • 3.0K
  • 07 May 2022
Topic Review
Machine Learning-Based Forecasting of Renewable Energy
With the increasing penetration of renewable energy sources (RES) into the electricity grid, accurate forecasting of their generation becomes crucial for efficient grid operation and energy management. Traditional forecasting methods have limitations, and thus machine learning (ML) and deep learning (DL) algorithms have gained popularity due to their ability to learn complex relationships from data and provide accurate predictions.
  • 3.0K
  • 27 Apr 2023
Topic Review
TBC-assisted Cooling Air System Simulation
Thermal barrier coating (TBC) and cooling air systems are among the technologies that have been introduced and applied in pursuing the extensive development of advanced gas turbine. TBC is used to protect the gas turbine components from the higher operating temperature of advanced gas turbine, whereas cooling air systems are applied to assist TBC in lowering the temperature exposure of protected surfaces. Generally, a gas turbine operates in three main operational modes, which are base load, peak load, and part peak load. TBC performance under these three operational modes has become essential to be studied, as it will provide the gas turbine owners not only with the behaviors and damage mechanism of TBC but also a TBC life prediction in a particular operating condition.
  • 3.0K
  • 23 Jun 2021
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.
  • 3.0K
  • 08 Nov 2022
Topic Review
Globalization of the Football Transfer Market
The football transfer market has been affected by the increased freedom of movement, trade and communications between different countries since the 1990s. This globalization of the transfer market has impacted the way in which football clubs trade with one another and the relationship between players and their clubs. When professional leagues were first founded, there were significant restrictions preventing footballers from joining whomever they liked. These limitations were put in place by both the clubs these players were tied to, and the leagues in which they played. International labor movement regulations and the difficulties of scouting less developed nations also hindered the development of a liberalized transfer market.
  • 3.0K
  • 11 Nov 2022
Biography
Simcha Jacobovici
Simcha Jacobovici (/ˈsɪmxə jəˈkoʊboʊvɪtʃ/, born April 4, 1953, Petah Tikva, Israel) is an Israeli-Canadian film director, producer, freelance journalist, and writer. His parents were from Iași, Romania.[1] Simcha Jacobovici earned a B.A. in Philosophy and Political Science (with honors) from McGill University and an M.A. in International Relations from the University of Toronto. He
  • 3.0K
  • 15 Nov 2022
Topic Review
First Assistant Engineer
A first assistant engineer (also called the second engineer in some countries) is a licensed member of the engineering department on a merchant vessel. This title is used for the person on a ship responsible for supervising the daily maintenance and operation of the engine department. They report directly to the chief engineer. On a merchant vessel, depending on term usage, "the First" or "the Second" is the marine engineer second in command of the engine department after the ship's chief engineer. Due to the supervisory role this engineer plays, in addition to being responsible for the refrigeration systems, main engines (steam/gas turbine, diesel), and any other equipment not assigned to the Second assistant engineer/third engineer or the Third assistant engineer/fourth engineer(s), he is typically the busiest engineer aboard the ship. If the engine room requires 24/7 attendance and other junior engineers can cover the three watch rotations, the first is usually a "day worker" from 0800-1700, with overtime hours varying according to ship/company. The first assistant/second engineer is usually in charge of preparing the engine room for arrival, departure, or standby and oversees major overhauls on critical equipment.
  • 3.0K
  • 03 Nov 2022
Topic Review
Sockpuppet (Internet)
A sockpuppet is an online identity used for purposes of deception. The term, a reference to the manipulation of a simple hand puppet made from a sock, originally referred to a false identity assumed by a member of an Internet community who spoke to, or about, themselves while pretending to be another person. The use of the term has expanded to now include other misleading uses of online identities, such as those created to praise, defend or support a person or organization, to manipulate public opinion, or to circumvent restrictions, suspension or an outright ban from a website. A significant difference between the use of a pseudonym and the creation of a sockpuppet is that the sockpuppet poses as an independent third-party unaffiliated with the main account operator. Sockpuppets are unwelcome in many online communities and forums.
  • 3.0K
  • 15 Nov 2022
Topic Review
Salicylic Acid Biosynthesis and Metabolism
Salicylic acid (SA) is an active secondary metabolite that occurs in bacteria, fungi, and plants. SA and its derivatives (collectively called salicylates) are synthesized from chorismate (derived from shikimate pathway). SA is considered an important phytohormone that regulates various aspects of plant growth, environmental stress, and defense responses against pathogens. Besides plants, a large number of bacterial species, such as Pseudomonas, Bacillus, Azospirillum, Salmonella, Achromobacter, Vibrio, Yersinia, and Mycobacteria, have been reported to synthesize salicylates through the NRPS/PKS biosynthetic gene clusters. This bacterial salicylate production is often linked to the biosynthesis of small ferric-ion-chelating molecules, salicyl-derived siderophores (known as catecholate) under iron-limited conditions. Although bacteria possess entirely different biosynthetic pathways from plants, they share one common biosynthetic enzyme, isochorismate synthase, which converts chorismate to isochorismate, a common precursor for synthesizing SA. Additionally, SA in plants and bacteria can undergo several modifications to carry out their specific functions.
  • 3.0K
  • 25 May 2021
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