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Topic Review
Microencapsulation
Microencapsulation is a well-known technology for the lipid delivery system. It prevents the oxidation of fatty acids and maintains the quality of lipid after extraction from oil seed and processing. In flaxseed oil, the amount of ω-3 and ω-6 polyunsaturated fatty acids are 39.90–60.42% and 12.25–17.44%, respectively.
  • 3.0K
  • 18 Feb 2021
Topic Review
Radical
In chemistry, a free radical is an atom, molecule, or ion that has at least one unpaired valence electron. With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize. Most organic radicals have short lifetimes. A notable example of a radical is the hydroxyl radical (HO·), a molecule that has one unpaired electron on the oxygen atom. Two other examples are triplet oxygen and triplet carbene (꞉CH2) which have two unpaired electrons. Radicals may be generated in a number of ways, but typical methods involve redox reactions. Ionizing radiation, heat, electrical discharges, and electrolysis are known to produce radicals. Radicals are intermediates in many chemical reactions, more so than is apparent from the balanced equations. Radicals are important in combustion, atmospheric chemistry, polymerization, plasma chemistry, biochemistry, and many other chemical processes. A majority of natural products are generated by radical-generating enzymes. In living organisms, the radicals superoxide and nitric oxide and their reaction products regulate many processes, such as control of vascular tone and thus blood pressure. They also play a key role in the intermediary metabolism of various biological compounds. Such radicals can even be messengers in a process dubbed redox signaling. A radical may be trapped within a solvent cage or be otherwise bound.
  • 3.0K
  • 15 Nov 2022
Topic Review
Ultra-Low-Frequency Oscillation
One of the prominent problems faced with hydro-dominant power system is ultra-low-frequency oscillation (ULFO) with a frequency deviation of 0.1 Hz lower, which is caused by the negative damping of hydro generators. ULFO might lead to an oscillation of all generators with the same oscillation frequency, restricting consumption of hydropower renewable energy.
  • 3.0K
  • 27 Oct 2020
Topic Review
Nitroaldol Reaction
The Henry Reaction (also referred to as the nitro-aldol reaction) is a classic carbon–carbon bond formation reaction in organic chemistry. Discovered in 1895 by the Belgian chemist Louis Henry (1834-1913), it is the combination of a nitroalkane and an aldehyde or ketone in the presence of a base to form β-Nitro alcohols. This type of reaction is commonly referred to as a "nitro-aldol" reaction (nitroalkane, aldehyde, and alcohol) It is nearly analogous to the aldol reaction that had been discovered 23 years prior that couples two carbonyl compounds to form β-hydroxy carbonyl compounds known as "aldols" (aldehyde and alcohol). The Henry reaction is a useful technique in the area of organic chemistry due to the synthetic utility of its corresponding products, as they can be easily converted to other useful synthetic intermediates. These conversions include subsequent dehydration to yield nitroalkenes, oxidation of the secondary alcohol to yield α-nitro ketones, or reduction of the nitro group to yield β-amino alcohols. Many of these uses have been exemplified in the syntheses of various pharmaceuticals including the β-blocker (S)-propranolol, the HIV protease inhibitor Amprenavir (Vertex 478), and construction of the carbohydrate subunit of the anthracycline class of antibiotics, L-Acosamine. The synthetic scheme of the L-Acosamine synthesis can be found in the Examples section of this article.
  • 3.0K
  • 14 Oct 2022
Topic Review
Distributed Element Circuit
Distributed element circuits are electrical circuits composed of lengths of transmission lines or other distributed components. These circuits perform the same functions as conventional circuits composed of passive components such as capacitors, inductors, and transformers. They are used mostly at microwave frequencies where conventional components are difficult or impossible to implement. A major advantage of distributed element circuits is that they can be produced cheaply as a printed circuit board for consumer products such as satellite television. They are also made in coaxial and waveguide formats for applications such as radar, satellite communication, and microwave links. A phenomenon that is much used in distributed element circuits is that a length of transmission line can be made to behave as a resonator. Distributed element components that do this include stubs, coupled lines, and cascaded lines. Circuits built from these components include filters, power dividers, directional couplers, and circulators. Distributed element circuits were investigated in the 1920s and 1930s but did not become important until World War II when they were used in radar. After the war their use was at first limited to military, space, and broadcasting infrastructure use but improvements in materials science in the field soon led to wider applications.
  • 3.0K
  • 17 Oct 2022
Topic Review
Orthodiagonal Quadrilateral
In Euclidean geometry, an orthodiagonal quadrilateral is a quadrilateral in which the diagonals cross at right angles. In other words, it is a four-sided figure in which the line segments between non-adjacent vertices are orthogonal (perpendicular) to each other.
  • 3.0K
  • 19 Oct 2022
Topic Review
List of Wartime Cross-Dressers
Many people have engaged in cross-dressing during wartime under various circumstances and for various motives. This has been especially true of women, whether while serving as a soldier in otherwise all-male armies, while protecting themselves or disguising their identity in dangerous circumstances, or for other purposes. Conversely, men would dress as women to avoid being drafted, the mythological precedent for this being Achilles hiding at the court of Lycomedes dressed as a girl to avoid participation in the Trojan War.
  • 3.0K
  • 08 Nov 2022
Topic Review
Targeted Muscle Reinnervation
Targeted Muscle Reinnervation (TMR) is considered to be an innovative and relevant surgical technique for improving the prosthetic control for people with different amputation levels of the limb. Indeed, TMR surgery makes it possible to obtain reinnervated areas that act as biological amplifiers of the motor control. On the technological side, a great deal of research has been conducted in order to evaluate various types of myoelectric prosthetic control strategies, whether direct control or pattern recognition-based control. In the literature, different control performance metrics, which have been evaluated on TMR subjects, have been introduced, but no accepted reference standard defines the better strategy for evaluating the prosthetic control. Indeed, the presence of several evaluation tests that are based on different metrics makes it difficult the definition of standard guidelines for comprehending the potentiality of the proposed control systems. Additionally, there is a lack of evidence about the comparison of different evaluation approaches or the presence of guidelines on the most suitable test to proceed for a TMR patients case study. This review aims at identifying these limitations byexamining the several studies in the literature on TMR subjects, with different amputation levels, and proposing a standard method for evaluating the control performance metrics.
  • 3.0K
  • 31 Mar 2021
Topic Review
Command Responsibility
Command responsibility (also superior responsibility, the Yamashita standard, and the Medina standard) is the legal doctrine of hierarchical accountability for war crimes. The legal doctrine of command responsibility was codified in the Hague Conventions of 1899 and 1907, and is partly based upon the American Lieber Code, a manual of war for the Union forces, authorised by President A. Lincoln in 1863, two years into the course of the U.S. civil war. The legal doctrine of command responsibility was first applied by the German Supreme Court, in the Leipzig War Crimes Trials (1921), which included the trial of Imperial German Army officer Emil Müller for war crimes committed during the First World War (1914–1918). The Yamashita standard derived from the incorporation to the U.S. Code of the legal doctrine of command responsibility, as codified in the two Hague Conventions. That legal precedent, decided by the U.S. Supreme Court, allowed the U.S. prosecution of the war-crimes case against General Tomoyuki Yamashita, for the atrocities committed by his soldiers in the Philippine Islands, in the Pacific Theatre (1941–1945) of the Second World War. A U.S. military tribunal charged Yamashita with "unlawfully disregarding, and failing to discharge, his duty as a commander to control the acts of members of his command, by permitting them to commit war crimes." The Medina standard expanded the U.S. Code to include the criminal liability of U.S. military officers for the war crimes committed by their subordinates, as are military officers of an enemy power, e.g. the war-crimes trial of Gen. Yamashita in 1945. The Medina standard originated from the charging, prosecution, and court-martial of U.S. Army Captain Ernest Medina in 1971, for not exercising his superior responsibility as company commander, by not acting to halt the commission of a war crime by his soldiers — the My Lai Massacre (16 March 1968) during the Vietnam War (1945–1975).
  • 3.0K
  • 31 Oct 2022
Topic Review
Perezhivanie and Its Application
Perezhivanie is a concept that was originally defined by Vygotsky, but it did not become a part of educational theory until recently. Today the concept has been revived, and it is now used as a way to include emotional aspects into education and educational research. The concept also provides a rationale for describing and forming personalised learning.
  • 3.0K
  • 17 Jan 2022
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
Pharmacological Effects of Houttuynia cordata Thunb (H. cordata)
Houttuynia cordata Thunb (H. cordata) is a rhizomatous, herbaceous, and perennial plant widely distributed in Asia. It has multiple chemical constituents, such as alkaloids, essential oils, phenolic acids, and flavonoids used against various health problems. The essential oils and flavonoids are the main components of H. cordata that play an essential role in disease treatment and traditional health care. Moreover, the leaves and stems of H. cordata have a long medicinal history in China. In addition, H. cordata is used against several health issues, such as cold, cough, fever, pneumonia, mumps, and tumors, due to its anti-inflammatory, anti-bacterial, anti-viral, anti-oxidant, and anti-tumor effects.
  • 3.0K
  • 07 Sep 2022
Topic Review
Substrate Integrated Waveguide
A Substrate integrated waveguide (SIW) (also known as post-wall waveguide or laminated waveguide) is a synthetic rectangular electromagnetic waveguide formed in a dielectric substrate by densely arraying metallized posts or via-holes which connect the upper and lower metal plates of the substrate. The waveguide can be easily fabricated with low-cost mass-production using through-hole techniques where the post walls consists of via fences. SIW is known to have similar guided wave and mode characteristics to conventional rectangular waveguide with equivalent guide wavelength. Since the emergence of new communication technologies in the 1990s, there has been an increasing need for high-performance millimeter-wave systems. These need to be reliable, low-cost, compact, and compatible with high-frequencies. Unfortunately, above 10 GHz, the well known microstrip and coplanar lines technologies cannot be used because they have high insertion and radiation losses at these frequencies. The rectangular waveguide topology can overcome these issues as it offers an excellent immunity against radiation losses and presents low insertion losses. But in their classical form, rectangular waveguide is not compatible with the miniaturization required by modern applications. The concept of SIW was developed in the early 2000s by Ke Wu to reconcile those requirements. The authors presented a platform for integrating all the components of a microwave circuit inside a single substrate, with a rectangular cross-section. Using a single substrate guarantees a limited volume and a simplicity of manufacture, while the rectangular cross-section of the line provides the advantages of the waveguide topology in terms of losses.
  • 3.0K
  • 27 Sep 2022
Topic Review
Kinesthetic Learning
Kinesthetic learning (American English), kinaesthetic learning (British English), or tactile learning is a learning style in which learning takes place by the students carrying out physical activities, rather than listening to a lecture or watching demonstrations. As cited by Favre (2009), Dunn and Dunn define kinesthetic learners as students who require whole-body movement to process new and difficult information.
  • 3.0K
  • 11 Oct 2022
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
Glucose
Glucose is a major macronutrient and a vital homeostatic factor in the regulation of energy metabolism maintained in a narrow range of 4.4 to 6.1 mmol/L or about 1.0 g/L in the blood of healthy humans as measured in the fasting state. However, glucose per se is not the predominant component of mixed food, and its main source in the diet is poly- and oligosaccharides, which undergo enzymatic hydrolysis to monomers in the small intestine during luminal and membrane digestion. Depending on the food composition, the site of the gastrointestinal tract (GIT) and time of the day, the postprandial glucose concentrations in the GIT lumen can vary in a large range and can be several times higher than in the blood.
  • 3.0K
  • 14 Aug 2021
Topic Review
Authenticity
Authenticity is a concept of personality in the fields of psychology, existential psychotherapy, existentialist philosophy, and aesthetics. In existentialism, authenticity is the degree to which a person's actions are congruent with his or her values and desires, despite external pressures to social conformity. The conscious Self comes to terms with the condition of Geworfenheit, of having been thrown into an absurd world (without values and without meaning) not of his or her own making, thereby encountering external forces and influences different from and other than the Self. In human relations, a person’s lack of authenticity is considered bad faith in dealing with other people and with one's self; thus, authenticity is in the instruction of the Oracle of Delphi: “Know thyself.” Concerning authenticity in art, the philosophers Jean Paul Sartre and Theodor Adorno held opposing views and opinions about jazz, a genre of American music; Sartre said that jazz is authentic and Adorno said that jazz is inauthentic. The musical subcultures of punk rock and Heavy metal require artistic authenticity, lest the community consider an artist to be a poseur for lacking authenticity (creative, musical, personal); likewise, artistic authenticity is integral to the genres of House music, Grunge, and Garage rock, Hip-hop, Techno, and show tunes. In every human activity, personal authenticity extends the instruction of the Oracle of Delphi: “Don’t merely know thyself — be thyself.”
  • 3.0K
  • 08 Oct 2022
Topic Review
Cosmopolitodus Hastalis
Cosmopolitodus hastalis, the broad-tooth mako (other common names include the extinct giant mako and broad-tooth white shark), is an extinct mackerel shark that lived from the Miocene epoch to the Pliocene epoch. Its teeth can reach lengths up to 3.5 in (7.5 cm) and are found worldwide. It is believed to be an ancestor to the great white shark, a fact supported by the transitional species Carcharodon hubbelli, and most likely would have been one of the major predators in its ecosystem; preying upon small whales and other mammals.
  • 3.0K
  • 28 Oct 2022
Topic Review
Genome Editing in Bacteria
Genome editing in bacteria encompasses a wide array of laborious and multi-step methods such as suicide plasmids. The discovery and applications of clustered regularly interspaced short palindromic repeats (CRISPR)-Cas based technologies have revolutionized genome editing in eukaryotic organisms due to its simplicity and programmability. 
  • 3.0K
  • 26 May 2021
Topic Review
COVID-19 Pandemic Impact Tourism Stakeholder
The impact of the COVID-19 pandemic on the tourism industry is still sustained, and the response of the tourism industry is an indispensable element that is increasingly recognized. This response has led to the emergence of literature about the impact of COVID-19 on the stakeholders of the tourism industry, thereby contributing to the industry. Nonetheless, criterion factors and investigated practices on the implementation of decision-making by stakeholders in the tourism industry have not been fully explored. Practically, the irresistible risk industry is already synonymous with tourism. Indeed, it is an unstable industry. 2003, 2 million tourists reduce of SARS. 2009, Global Economic Crisis tourist 37 million reduce. 2020, the COVID-19 pandemic, the world's borders are blocked, all international travel is stopped, and the mobility of tourists is prohibited. However, effective decision-making is lacking, and few studies have determined the solutions in the tourism industry of stakeholder. How the tourism industry survives under the crisis context is an urgent issue.
  • 3.0K
  • 11 Aug 2021
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