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Topic Review
Hepatitis Delta Virus
Hepatitis Delta Virus (HDV) is the cause of hepatitis D, a relatively rare but aggressive form of viral hepatitis developing in patients co-infected with hepatitis B virus (HBV). HDV infection is associated with HBV infection since the defective HDV needs HBV to infect and replicate in the liver. Even if not a frequent cause of chronic liver disease, HDV infection is responsible for an aggressive progression of hepatitis towards advanced liver disease.
  • 1.5K
  • 10 May 2022
Topic Review
Polypropylene Extrusion Molding Production Quality
Polypropylene is derived from the reaction of petrochemical propylene gas with a density of 0.89–0.94 g/cm3. It is a lightweight plastic material with a semitransparent white color and has a lower cost than other plastic materials.
  • 1.5K
  • 02 Jun 2022
Topic Review
Horror Vacui
In physics, horror vacui, or plenism (/ˈpliːnɪzəm/), commonly stated as "nature abhors a vacuum", is a postulate attributed to Aristotle, who articulated a belief, later criticized by the atomism of Epicurus and Lucretius, that nature contains no vacuums because the denser surrounding material continuum would immediately fill the rarity of an incipient void. He also argued against the void in a more abstract sense (as "separable"), for example, that by definition a void, itself, is nothing, and following Plato, nothing cannot rightly be said to exist. Furthermore, insofar as it would be featureless, it could neither be encountered by the senses, nor could its supposition lend additional explanatory power. Hero of Alexandria challenged the theory in the first century CE, but his attempts to create an artificial vacuum failed. The theory was debated in the context of 17th-century fluid mechanics, by Thomas Hobbes and Robert Boyle, among others, and through the early 18th century by Sir Isaac Newton and Gottfried Leibniz.
  • 1.5K
  • 08 Oct 2022
Topic Review
Spectrum Reallocation
Middle 20th century frequency allocation assigned much of the radio spectrum to broadcasting. Late in the century, other uses arose and in United States, spectrum reallocation mostly refers to reassigning frequency bands to uses such as wireless broadband, trunking, or point-to-point microwave services. Spectrum reallocation is being done partly through auctions authorized by Title VI (The Spectrum Act) of the payroll tax cut extension passed by Congress on February 17, 2012. Many broadcasters oppose this plan, even though they have been assured that stations will not be forced off the air.
  • 1.5K
  • 14 Oct 2022
Topic Review
Wnt Signaling in Pain
The heterogeneity of Wnt signaling starts with the ligand itself. There are 19 members of the Wnt family in humans and rodents, each one with a different expression pattern and function. These ligands bind different kinds of receptors: the classical Frizzled (Fzd) receptors (a family of G protein-coupled receptors that comprises 10 members in vertebrates), which are frequently associated with co-receptors, such as low-density lipoprotein receptor-related protein 5/6 (LRP5/6), the RTKs, receptor-like tyrosine kinase (Ryk), receptor tyrosine kinase-like orphan receptor 2 (Ror2), protein-tyrosine kinase-7 (PKT7), and muscle-specific kinase (MuSK), or proteoglycans. Usually, many ligands can bind the same receptor and one ligand can bind different receptors, increasing the complexity of Wnt signaling.
  • 1.5K
  • 24 Oct 2022
Topic Review
IT Baseline Protection Catalogs
The IT Baseline Protection Catalogs, or IT-Grundschutz-Kataloge, ("IT Baseline Protection Manual" before 2005) are a collection of documents from the Germany Federal Office for Security in Information Technology (BSI) that provide useful information for detecting weaknesses and combating attacks in the information technology (IT) environment (IT cluster). The collection encompasses over 3000 pages, including the introduction and catalogs. It serves as the basis for the IT baseline protection certification of an enterprise.
  • 1.5K
  • 31 Oct 2022
Topic Review
Goonda
"Goonda" is a term in Indian English, Pakistani English, and Bangladeshi English for a hired thug. It is both a colloquial term and defined and used in laws, generally referred to as Goonda Acts.
  • 1.5K
  • 10 Nov 2022
Topic Review
CASA C-101
The CASA C-101 Aviojet is a low-wing single engine jet-powered advanced trainer and light attack aircraft designed and manufactured by Spanish aircraft company Construcciones Aeronáuticas SA (CASA). The C-101 was developed in response to a Spanish Air Force requirement, which needed a replacement for the already outdated Hispano Saeta. During 1975, CASA commenced work on what would become the C-101. In addition to its own design team, technical assistance was provided by Germany's Messerschmitt-Bölkow-Blohm (MBB) and the United States' Northrop. During June 1977, the first of four prototypes performed the type's maiden flight. The design was somewhat reminiscent of other jet trainers of the era, such as the BAE Hawk and the Alpha Jet, but was less aerodynamically sophisticated, being equipped with an unswept wing. Performance of the C-101 during flight testing was reported in excess of predictions. On 17 March 1980, the first examples were introduced to operational service with the Spanish Air Force, which would be the principal customer for the C-101. The initial model possessed only a limited weapons capability, this attack capability was expanded upon later-built aircraft. Several models were exported to overseas operators; the C-101 has been adopted by the Chilean Air Force , Honduran Air Force and the Royal Jordanian Air Force . A final improved model, designated C-101DD, was demonstrated but did not find customers and thus it did not enter serial production. In addition to its use as a trainer aircraft, it has been used to perform aerobatics; in the latter context, it has been flown by the Patrulla Aguila aerobatics team. As of 2019, the C-101 remains in service in the Spanish Air Force and several other countries. Early on the 2010s there were talks about the replacement of the C-101. Finally, in 2020 it was decided that the C-101 would be replaced by the Pilatus PC-21 (24) and the Airbus Future Jet Trainer (50 - 55).
  • 1.5K
  • 22 Nov 2022
Topic Review
Halotolerant Plant Growth-Promoting Rhizobacteria in Mitigating Salinity Stress
Soil salinity is one of the major abiotic constraints in agricultural ecosystems worldwide. High salinity levels have negative impacts on plant growth and yield, and affect soil physicochemical properties. Salinity also has adverse effects on the distribution and abundance of soil microorganisms. Halotolerant plant growth-promoting rhizobacteria (HT-PGPR) secrete secondary metabolites, including osmoprotectants, exopolysaccharides, and volatile organic compounds. The importance of these compounds in promoting plant growth and reducing adverse effects under salinity stress has been widely recognised. HT-PGPR are emerging as effective biological strategies for mitigating the harmful effects of high salinity; improving plant growth, development, and yield; and remediating degraded saline soils. 
  • 1.5K
  • 01 Feb 2023
Topic Review
Vitamin K in Chronic Obstructive Pulmonary Disease
Although defined by the presence of airflow obstruction and respiratory symptoms, patients with chronic obstructive pulmonary disease (COPD) are characterized by multimorbidity. Numerous co-occurring conditions and systemic manifestations contribute to the clinical presentation and progression of COPD. Vitamin A and vitamin D have been related to COPD pathogenesis. Another fat-soluble vitamin, vitamin K, has been put forward to exert protective roles in COPD. Vitamin K is an unequivocal cofactor for the carboxylation of coagulation factors, but also for extra-hepatic proteins including the soft tissue calcification inhibitor matrix Gla-protein and the bone protein osteocalcin.
  • 1.5K
  • 10 May 2023
Topic Review
Research Progress on Cu–15Ni–8Sn Alloys
The Cu–15Ni–8Sn (C72900) alloy is a typical spinodal hardened copper alloy engineered for high strength, elasticity, and stress relaxation resistance. Compared with Cu-Be alloy, the comprehensive properties of Cu-15Ni-8Sn alloy are equal, and it has no toxicity during manufacturing and processing. In addition, the properties of Cu-15Ni-8Sn alloy are much better than those of Cu-Be alloy at high temperature.
  • 1.5K
  • 06 Sep 2023
Topic Review
Electronic Structure and Chemical Bonding of Transition-Metal Monoborides
Boron presents an important role in chemistry, biology, and materials science. Diatomic transition-metal borides (MBs) are the building blocks of many complexes and materials, and they present unique electronic structures with interesting and peculiar properties and a variety of bonding schemes which are analyzed here. Comparisons between MB molecules along the three rows are presented, and their differences and similarities are analyzed. The bonding of the diatomic borides is also described. Three of them RhB(X1Σ+), RuB(X2Δ) and TcB(X3Σ−)  form quadruple σ2σ2π2π2 bonds in their X states. The RhB form quadruple bond also in two low-lying excited states.
  • 1.5K
  • 11 Dec 2023
Topic Review
Epicardial Thoracoscopic Ablation
In this study we evaluated atrial fibrillation (AF) recurrence and Sarcoplasmic Endoplasmic Reticulum Calcium ATPase (SERCA) levels in patients treated by epicardial thoracoscopic ablation for persistent AF. This was a prospective, multicenter, observational study to recruit patients with persistent AF receiving an epicardial thoracoscopic pulmonary vein isolation. About 27 patients, responders (n = 15) did not present AF recurrence after epicardial ablation at one-year follow-up; these patients displayed a marked remodeling of the left atrium, with a significant reduction of inflammatory cytokines, B type natriuretic peptide (BNP), and increased levels of SERCA compared to baseline and to non responders (p < 0.05). Furthermore, mean AF duration (Heart rate (HR) 1.235 (1.037-1.471), p < 0.05), Left atrium volume (LAV) (HR 1.755 (1.126-2.738), p < 0.05), BNP (HR 1.945 (1.895-1.999), p < 0.05), and SERCA (HR 1.763 (1.167-2.663), p < 0.05) were predictive of AF recurrence. Therefore, our data indicate for the first time that baseline values of SERCA in patients with persistent AF might be predictive of failure to epicardial ablative approach. Intriguingly, epicardial ablation was associated with increased levels of SERCA in responders. Thus, SERCA might be an innovative therapeutic target to improve the response to epicardial ablative treatments.
  • 1.5K
  • 28 Oct 2020
Topic Review
Perceived Value’ Predictive Relationship
Ecotourism development is a distinct market phenomenon and a necessary form of sustainable tourism, which grows three times faster than tourism in general. Ecotourism’s rising popularity worldwide has encouraged tourist destinations to receive more and more tourists who like contact with nature and are willing to comply with the protection standards of the natural area chosen. 
  • 1.5K
  • 28 Jul 2021
Topic Review
Green Tea Suppresses Brain Aging
Epidemiological studies have demonstrated that the intake of green tea is effective in reducing the risk of dementia. The most important component of green tea is epigallocatechin gallate (EGCG). Both EGCG and epigallocatechin (EGC) have been suggested to cross the blood–brain barrier to reach the brain parenchyma, but EGCG has been found to be more effective than EGC in promoting neuronal differentiation.
  • 1.5K
  • 19 Aug 2021
Topic Review
Food Losses and Waste of Food
In recent times the issue of food losses and waste of food (FLW) has received increased academic and political attention. Although the definition of FLW is not clear, the truth is that globally roughly one-third of food is not consumed and is wasted, equivalent to 1.3. billion tonnes per year. The reasons for FLW differ between countries. In developed countries, most FLW occurs at the retail, foodservice and, home stages of the food supply chain for a variety of reasons. For instance, food not used in time, burning, spoilage, personal preferences or, leftover waste. While in developing countries FLW is mainly due to the absence of infrastructure, lack of knowledge and, investment in storage technologies.
  • 1.5K
  • 02 Feb 2022
Topic Review
Drug Reaction with Eosinophilia and Systemic Symptoms
Drug reaction with eosinophilia and systemic symptoms (DReSS), also known as drug-induced hypersensitivity syndrome (DiHS), is a severe, systemic, T cell mediated drug reaction with combinations of cutaneous, hematologic, and internal organ involvement. Pathogenesis of DReSS is multi-factorial, involving drug-exposure, genetic predisposition through specific human leukocyte antigen (HLA) alleles and metabolism defects, viral reactivation, and immune dysregulation. Clinical features of this condition are delayed, stepwise, and heterogenous, making this syndrome challenging to recognize and diagnose.
  • 1.5K
  • 13 May 2022
Topic Review
Blockchains and Artificial Intelligence
It is undeniable that the adoption of blockchain- and artificial intelligence (AI)-based paradigms is proceeding at lightning speed. Both paradigms provide something new to the market, but the degree of novelty and complexity of each is different. In the age of digital money, blockchains  may automate installments to allow for the safe, decentralized exchange of personal data, information, and logs. AI and blockchains are two of the most talked about technologies right now. Using a decentralized, secure, and trustworthy system, blockchain technology can automate bitcoin payments and provide users access to a shared ledger of records, transactions, and data. Through the use of smart contracts, a blockchain may also regulate user interactions without the need for a central authority. As an alternative, AI provides robots with the ability to reason and make decisions and human-level intellect.
  • 1.5K
  • 26 Dec 2022
Topic Review
Analysis of Hydrocarbons from Waste Plastic
Ecosystem destruction is one of today’s significant challenges due to fast industrialisation and an increasing population. It takes several years for solid trash, such as plastic bottles and super-market bags, to decompose in nature. In addition, plastic disposal techniques such as landfilling, reuse, and incineration pose significant threats to human health and the environment.
  • 1.5K
  • 27 Dec 2022
Topic Review
Thermosensitive Liposomal Doxorubicin
Thermo-sensitive liposomes (TSLs) offer the most promising approach for more efficient doxorubicin (DOX) delivery to the tumor at mild hyperthermic temperatures (39-42 ̊C)
  • 1.5K
  • 24 Mar 2023
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