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Topic Review
Polyetheretherketone
Polyetheretherketone (PEEK) is an aromatic, semi-crystalline linear thermoplastic polymer.
  • 3.0K
  • 18 Mar 2021
Topic Review
Staphylococcus pseudintermedius
Staphylococcus pseudintermedius is a pathogenic bacterium of concern within the veterinary sector and is involved in numerous infections in canines, including topical infections such as canine pyoderma and otitis externa, as well as systemic infections within the urinary, respiratory and reproductive tract. The high prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) within such infections is a growing concern.
  • 3.0K
  • 14 May 2021
Topic Review
Bacterial Resistance to Antimicrobial Agents
Bacterial pathogens as causative agents of infection constitute an alarming concern in the public health sector. In particular, bacteria with resistance to multiple antimicrobial agents can confound chemotherapeutic efficacy towards infectious diseases. Multidrug-resistant bacteria harbor various molecular and cellular mechanisms for antimicrobial resistance. These antimicrobial resistance mechanisms include active antimicrobial efflux, reduced drug entry into cells of pathogens, enzymatic metabolism of antimicrobial agents to inactive products, biofilm formation, altered drug targets, and protection of antimicrobial targets. These microbial systems represent suitable focuses for investigation to establish the means for their circumvention and to reestablish therapeutic effectiveness.
  • 3.0K
  • 01 Aug 2022
Topic Review Peer Reviewed
COVID-19 and Peace in Conflict-Affected Areas
The relationship between COVID-19 and peace has been considered from a variety of perspectives. In addition, different empirical studies on the link between the pandemic and peace in conflict-affected areas exist. However, little work has been performed on examining these studies to highlight key findings on the theme of COVID-19 and peace in conflict-affected areas. A conflict-affected area is a country, or part of a country, where widespread violence or armed conflict was present when COVID-19 emerged in December 2019, or that was transitioning from recent armed conflict to peace by the time the disease arose. What do we know, so far, about how peace has been affected by the COVID-19 pandemic in conflict-affected areas? To address this question, this paper begins by recognizing the multidimensionality of peace and clarifying that the main aspects of peace in conflict-affected areas being considered in the article are relations between conflict parties, peace efforts, and peace processes. Afterwards, the paper discusses existing evidence regarding the impact of COVID-19 and state responses to it on these components of peace in conflict-affected areas. The conflict-affected areas considered include Afghanistan, Colombia, Iraq, Israel-Palestine, Libya, Myanmar, Nigeria, South Sudan, Syria, the Philippines, Yemen, and other zones. The central finding of the article is that the existing studies on COVID-19 and peace in conflict-affected areas present mixed findings. On the one hand, the virus generated opportunities for cooperation between conflict parties in some cases, such as in the West Bank and Gaza Strip of Israel-Palestine. However, on the other hand, it created conditions that enabled conflict and impeded peace efforts and processes in many or most conflict-affected areas. The paper explains that two factors that determined how the disease affected peace in conflict-affected and non-conflict-affected areas are the pre-COVID-19 political and socio-economic conditions in an area, and how state and non-state actors responded to the pandemic. The article closes with a summary of the discussion and identification of its major limitations. 
  • 3.0K
  • 28 Sep 2022
Topic Review
Biosynthesis Investigations of Terpenoids Antimicrobial Agents
Terpenoids, also known as isoprenoids, are one of the largest natural product families, constituting more than 40,000 primary and secondary metabolites, including monoterpenes (53%), diterpenoids (1%), sesquiterpenes (28%), and others (18%). The basic unit of terpenes is the isoprene unit (C5H8), which is a simple hydrocarbon. It is the main precursor and could be post-modified through the cytosolic mevalonate (MVA) pathway or the plastid methyl erythritol phosphate (MEP) pathway. Terpenoids are a major source of bioactive natural products. 
  • 3.0K
  • 07 Nov 2022
Topic Review
Plasticized Polyvinyl Chloride
Plasticized polyvinyl chloride (p-PVC)—widely present in modern and contemporary art collections as objects, clothing and footwear, furniture and upholstery, and housewares and toys—is known to deteriorate very rapidly in museum collections. The tendency of colorless p-PVC-based objects to yellowing-browning in combination with stickiness and cracking are the main issues of this important plastic material, which require the attention of conservation scientists in cooperation with conservators, engineers, curators, and art historians.
  • 3.0K
  • 19 Dec 2023
Topic Review
Nucleotide Excision Repair
Nucleotide excision repair (NER) is the most versatile DNA repair pathway, which can remove diverse bulky DNA lesions destabilizing a DNA duplex. NER substrates are UV photoproducts, e.g., cyclobutane pyrimidine dimers (CPDs), pyrimidine-pyrimidone-(6-4)-photoproducts (6-4PPs), intrastrand crosslinks, and bulky adducts of DNA bases with reactive metabolites of some chemical carcinogens or chemotherapeutic agents. These kinds of lesions can be substrates for two NER sub-pathways—global genome NER (GG-NER) and transcription-coupled NER (TC-NER)—that overlap, except for the mode of DNA damage recognition. NER defects cause several autosomal recessive genetic disorders. Xeroderma pigmentosum (XP) is one of the NER-associated syndromes characterized by low efficiency of the removal of bulky DNA adducts generated by ultraviolet radiation. XP patients have extremely high ultraviolet-light sensitivity of sun-exposed tissues, often resulting in multiple skin and eye cancers.
  • 3.0K
  • 12 Oct 2021
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
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
Topic Review
Process Intensification
Process Intensification (PI) is a vast and growing area in Chemical Engineering, which deals with the enhancement of current technology to enable improved efficiency; energy, cost, and environmental impact reduction; small size & modularization; and better integration with the other equipment. Since process intensification results in novel, but complex, systems, it is necessary to rely on optimization and control techniques that can cope with such new processes. 
  • 3.0K
  • 09 Dec 2021
Topic Review
Neurogenic Inflammation
Migraine is a primary headache disorder characterized by a unilateral, throbbing, pulsing headache, which lasts for hours to days, and the pain can interfere with daily activities. It exhibits various symptoms, such as nausea, vomiting, sensitivity to light, sound, and odors, and physical activity consistently contributes to worsening pain. 
  • 3.0K
  • 28 Mar 2022
Topic Review
Lipid Metabolism in COVID-19
The current Coronavirus disease 2019 or COVID-19 pandemic has infected over two million people and resulted in the death of over one hundred thousand people at the time of writing this review. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). Even though multiple vaccines and treatments are under development so far, the disease is only slowing down under extreme social distancing measures that are difficult to maintain. SARS-COV2 is an enveloped virus that is surrounded by a lipid bilayer. Lipids are fundamental cell components that play various biological roles ranging from being a structural building block to a signaling molecule as well as a central energy store. The role lipids play in viral infection involves the fusion of the viral membrane to the host cell, viral replication, and viral endocytosis and exocytosis. Since lipids play a crucial function in the viral life cycle, we asked whether drugs targeting lipid metabolism, such as statins, can be utilized against SARS-CoV-2 and other viruses. In this review, we discuss the role of lipid metabolism in viral infection as well as the possibility of targeting lipid metabolism to interfere with the viral life cycle.
  • 3.0K
  • 28 Oct 2020
Topic Review
Methyl Benzoate as Insecticide
The methyl benzoate is an effective pesticide against a range of different agricultural, stored product, and urban insect pests. Methyl benzoate has several important modes of action, including as a contact toxicant, a fumigant, an ovicidal toxin, an oviposition deterrent, a repellent, and an attractant.
  • 3.0K
  • 31 Mar 2022
Topic Review
Hybrid Log-Gamma
Hybrid Log-Gamma (HLG) is a backwards-compatible high dynamic range (HDR) standard that was jointly developed by the BBC and NHK. It provides the ability to encode a wide dynamic range, while still being compatible with the existing transmission standards in the standard dynamic range (SDR) region. This makes HLG compatible with Standard Dynamic Range displays, reducing complexity and cost for both equipment manufacturers and content distributors. The HLG standard is royalty-free and was approved as ARIB STD-B67 by the Association of Radio Industries and Businesses (ARIB). HLG is defined in ATSC 3.0, Digital Video Broadcasting (DVB) UHD-1 Phase 2, and International Telecommunication Union (ITU) Rec. 2100. HLG is supported by HDMI 2.0b, HEVC, VP9, and H.264/MPEG-4 AVC, and is used by video services such as BBC iPlayer, DirecTV, Freeview Play, and YouTube. HLG transfer function is backward compatible with SDR's gamma curve. However HLG is commonly used with Rec. 2020 color primaries which produce a de-saturated image with visible hue shifts on non-compatible devices. HLG is therefore backward compatible with SDR-UHDTV and will show color distortion on common SDR devices that only support Rec. 709 color primaries.
  • 3.0K
  • 14 Oct 2022
Topic Review
Nine-Point Circle
In geometry, the nine-point circle is a circle that can be constructed for any given triangle. It is so named because it passes through nine significant concyclic points defined from the triangle. These nine points are: The nine-point circle is also known as Feuerbach's circle, Euler's circle, Terquem's circle, the six-points circle, the twelve-points circle, the n-point circle, the medioscribed circle, the mid circle or the circum-midcircle. Its center is the nine-point center of the triangle.
  • 3.0K
  • 19 Oct 2022
Topic Review
Citizenship
Citizenship is a relationship between an individual and a state to which the individual owes allegiance and in turn is entitled to its protection.(quoted) Each state determines the conditions under which it will recognize persons as its citizens, and the conditions under which that status will be withdrawn. Recognition by a state as a citizen generally carries with it recognition of civil, political, and social rights which are not afforded to non-citizens. In general, the basic rights normally regarded as arising from citizenship are the right to a passport, the right to leave and return to the country/ies of citizenship, the right to live in that country and to work there. Some countries permit their citizens to have multiple citizenships, while others insist on exclusive allegiance. A person who does not have citizenship of any state is said to be stateless, while one who lives on state borders whose territorial status is uncertain is a border-lander.
  • 3.0K
  • 18 Nov 2022
Topic Review
Detection of Image Steganography
As internet traffic grows daily, so does the need to protect it. Network security protects data from unauthorized access and ensures their confidentiality and integrity. Steganography is the practice and study of concealing communications by inserting them into seemingly unrelated data streams (cover media). Investigating and adapting machine learning models in digital image steganalysis is becoming more popular.
  • 3.0K
  • 28 Jun 2023
Topic Review
Sample Preparation Techniques Used in Food Analysis
Food samples are complex heterogenous matrices, where all analytes are distributed in a random manner. Food analysis involves sampling, homogenization, and sample preparation that increase the analytical accuracy and precision. Focusing on sample preparation it usually involves storage, particle size reduction, homogenization, weighting, dilution, filtration, extraction, clean-up, and derivatization. Proper sample preparation protocols result in matrix interference elimination and analyte preconcentration, thus affecting the selectivity, sensitivity, detection capability, and the overall performance of an analytical technique. The most time-consuming step in analytical method development is the optimization of the sample preparation protocol that includes analyte extraction and clean-up. Some of the most common sample preparation techniques used in food analysis are liquid-liquid extraction (LLE), solid-liquid extraction (SLE), solid-phase extraction (SPE), solid-phase microextraction (SPME), stir bar sorptive extraction (SBSE), supercritical fluid extraction (SFE), accelerated solvent extraction (ASE), ultrasonic, and Soxhlet extraction.
  • 3.0K
  • 17 Jul 2023
Topic Review
Synthesis of nucleobase-modified RNA oligonucleotides
The review summarizes the methods of site-specific incorporation of nucleobase-modified units into RNA oligomers via the post-synthetic strategy including recently discovered native hypermodified functional groups, fluorescent dyes, photoreactive groups, disulfide crosslinks, and nitroxide spin labels.
  • 3.0K
  • 06 Aug 2020
Topic Review
The Impact of Airbnb Brand on Consumer Involvement
Airbnb is one of the leading businesses in the hospitality industry, and is one of the fastest growing corporations in sharing economy services. The brand operates on a marketplace platform, and connects travelers with hosts all over the world. Trust is essential for purchase intentions, particularly online, and the degree of involvement determines whether or not the brand is committed to its promises. In the context of Airbnb, users pay for their services online, and are allowed to present reviews for future travelers. Unlike other business models, Airbnb has to preserve its image by providing innovative and quality services for travelers, especially in the hospitality industry, where the product attributes only differ slightly. With Airbnb’s rapid growth, the aspects of brand personality become critical when establishing a positive brand image and positioning the company as a platform that provides unique experiences to its users and possesses a distinct identity.
  • 3.0K
  • 20 Jul 2022
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