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Topic Review
US Airways Livery
US Airways' aircraft livery has varied both under the US Airways and USAir name. In general the Express and Shuttle divisions have had liveries that closely parallel the company-wide livery at the time. The US Airways livery has been replaced with the new American Airlines livery, in accordance with their merger.
  • 7.0K
  • 16 Nov 2022
Topic Review
Construction 4.0
Construction 4.0 is a variety of interdisciplinary technologies, methodologies and concepts that digitize, automate and integrate the construction process at all stages of the value chain
  • 7.0K
  • 27 Mar 2023
Topic Review
Wooden Boats of World War 2
Splinter fleet or Splinter navy was a nickname given to the wooden boats used in World War II. The boats served in many different roles during the war. These boats were built in small boatyards on the West coast and East coast, Great Lakes and the Gulf of Mexico. They could be built quickly, in just 60 to 120 days. Most of the boats were built by boatyards that already had the tools and knowledge from building yachts, sailboats and motor boats. Many were built by craftsmen in family-owned small businesses. Under the Emergency Shipbuilding Program and War Shipping Administration contracts went out to over fifty boatyards across the country. The boats were built for the US Navy, the, United States Army Air Forces , United States Coast Guard, and US Army. Some of the wooden boats went to Allied nations on the Lend-Lease program. In addition to new boat construction, some wooden boats built between 1910 and 1941 were acquired for the war effort, some used as-is and others converted for war use. Wooden boats have lighter weight and are easier to repair than steel hull boats. These wooden boats ranged from 19 to 200 feet in length. Some worked near shore and others working in the open ocean, called the Blue-water navy. The Splinter fleet is in contrast to the more common steel hull war ships and Merchant Marine ships. After the war, many of these boats were deemed not needed. Many were abandoned or destroyed, a few served in the Korean war and a few in the Vietnam War, some sold to private and some donated. During World War I there was a debate as to if wooden boats and ships should be used in war time. William Denman, President of the Emergency Fleet Corporation supported the building of wooden ships for the war and General Goethals disapproved. In the end, both men turned in their resignation over the heated debate. During World War II the situation was different. There was a shortage of steel and steel shipyards, so there was no debate about the need for a vast wooden fleet of boats and ships.
  • 7.0K
  • 14 Oct 2022
Topic Review
Liquid Hydrogen
Decarbonization plays an important role in future energy systems for reducing greenhouse gas emissions and establishing a zero-carbon society. Hydrogen is believed to be a promising secondary energy source (energy carrier) that can be converted, stored, and utilized efficiently, leading to a broad range of possibilities for future applications. 
  • 7.0K
  • 27 Sep 2021
Topic Review
Early Germanic Law
Early Germanic law was the form of law followed by the early Germanic peoples. It was an important element of early Germanic culture. Several Latin law codes of the Germanic peoples written in the Early Middle Ages after the Fall of the Western Roman Empire (also known as leges barbarorum "laws of the barbarians") survive, dating to between the 5th and 9th centuries. They are influenced by Roman law, canon law, and earlier tribal customs. Central and West European Germanic law differed from North Germanic law. Germanic law was codified in writing under the influence of Roman law; previously it was held in the memory of designated individuals who acted as judges in confrontations and meted out justice according to customary rote, based on careful memorization of precedent. Among the Franks they were called rachimburgs. "Living libraries, they were law incarnate, unpredictable and terrifying." Power, whose origins were at once said to be magical, divine, and military, was, according to Michel Rouche, exercised jointly by the "throne-worthy" elected king and his free warrior companions. Oral law sufficed as long as the warband was not settled in one place. Germanic law made no provisions for the public welfare, the res publica of Romans. The language of all these continental codes was Latin; the only known codes drawn up in any Germanic language were the Anglo-Saxon laws, beginning with the Laws of Æthelberht (7th century). In the 13th century customary Saxon law was codified in the vernacular as the Sachsenspiegel. All these laws may be described in general as codes of governmental procedure and tariffs of compositions. They all present somewhat similar features with Salic law, the best-known example, but often differ from it in the date of compilation, the amounts of fines, the number and nature of the crimes, the number, rank, duties and titles of the officers, etc. In Germanic Europe in the Early Middle Ages, every man was tried according to the laws of his own ethnicity, whether Roman, Salian or Ripuarian Frank, Frisian, Burgundian, Visigoth, Bavarian etc. A number of separate codes were drawn up specifically to deal with cases between ethnic Romans. These codes differed from the normal ones that covered cases between Germanic peoples, or between Germanic people and Romans. The most notable of these are the Lex Romana Visigothorum or Breviary of Alaric (506), the Lex Romana Curiensis and the Lex Romana Burgundionum.
  • 7.0K
  • 02 Dec 2022
Topic Review
AK-630
The AK-630 is a Soviet and Russian fully automatic naval close-in weapon system based on a six-barreled 30 mm rotary cannon. In "630", "6" means 6 barrels and "30" means 30 mm. It is mounted in an enclosed automatic turret and directed by MR-123 radar and television detection and tracking. The system's primary purpose is defense against anti-ship missiles and other precision guided weapons. However it can also be employed against fixed or rotary wing aircraft, ships and other small craft, coastal targets, and floating mines. Once operational, this weapon system was rapidly adopted, with up to 8 units installed in every new Soviet warship (from mine-hunters to aircraft carriers), and hundreds produced in total.
  • 7.0K
  • 08 Oct 2022
Topic Review
UAV-based IoT
The Internet of Things (IoT), which consists of a large number of small low-cost devices, has become a leading solution for smart cities, smart agriculture, smart buildings, smart grids, e-healthcare, etc. Integrating unmanned aerial vehicles (UAVs) with IoT can result in an airborne UAV-based IoT (UIoT) system and facilitate various value-added services from sky to ground. In addition to wireless sensors, various kinds of IoT devices are connected in UIoT, making the network more heterogeneous. In a UIoT system, for achieving high throughput in an energy-efficient manner, it is crucial to design an efficient medium access control (MAC) protocol because the MAC layer is responsible for coordinating access among the IoT devices in the shared wireless medium. Thus, various MAC protocols with different objectives have been reported for UIoT.
  • 7.0K
  • 07 Dec 2020
Topic Review
Secretory IgA
Secretory IgA (SIgA) is the dominant antibody class in mucosal secretions, it is also present in saliva and breast milk. The majority of plasma cells producing SIgA are located within mucosal membranes lining the intestines, airway and reproductive tracts, as well as mammary gland. SIgA protects against the adhesion of pathogens and their penetration into the mucosal barriers. Moreover, SIgA regulates microbiota composition at mucosa sites and provides local homeostasis.
  • 7.0K
  • 17 Jan 2021
Topic Review
NASDAQ-100
The NASDAQ-100 (^NDX) is a stock market index made up of 103 equity securities issued by 100 of the largest non-financial companies listed on the Nasdaq stock market. It is a modified capitalization-weighted index. The stocks' weights in the index are based on their market capitalizations, with certain rules capping the influence of the largest components. It is based on exchange, and it does not have any financial companies. The financial companies were put in a separate index, the NASDAQ Financial-100.
  • 7.0K
  • 19 Oct 2022
Topic Review
Hallmarks and Significance of Apoptosis
Apoptosis is the elimination of functionally non-essential, neoplastic, and infected cells via the mitochondrial pathway or death receptor pathway. The process of apoptosis is highly regulated through membrane channels and apoptogenic proteins. Apoptosis maintains cellular balance within the human body through cell cycle progression. Loss of apoptosis control prolongs cancer cell survival and allows the accumulation of mutations that can promote angiogenesis, promote cell proliferation, disrupt differentiation, and increase invasiveness during tumor progression. The apoptotic pathway has been extensively studied as a potential drug target in cancer treatment. 
  • 7.0K
  • 14 Feb 2023
Topic Review
Plasma Treatment for Seed Germination and Plant Growth
Low-temperature atmospheric pressure plasma has been used in various fields such as plasma medicine, agriculture, food safety and storage, and food manufacturing. In the field of plasma agriculture, plasma treatment improves seed germination, plant growth, and resistance to abiotic and biotic stresses, allows pesticide removal, and enhances biomass and yield.
  • 7.0K
  • 27 May 2022
Topic Review
Crosslinking Agent for on Cellulose-Based Hydrogels
Hydrogels are interlinked hydrophilic polymers that are insoluble in water but are capable of absorbing large amounts of water through the swelling process. During the swelling process, the polar groups in the polymer chain swiftly draw the first water molecules into the hydrogel network (bound water). The hydrogel network absorbs more water molecules due to the osmotic pressure of the interstitial water and free water. Both synthetic and natural polymers can be used to create hydrogels. Natural polymer-based hydrogels are typically chosen because of their excellent biocompatibility and biodegradability. In addition, natural polymers are less expensive than synthetic ones.  A crosslinking agent is used to strengthen the properties of the hydrogel. A chemical crosslinking agent is used more often than a physical crosslinking agent. In a chemical crosslinking agent, there are two types of crosslinking agents, which is synthetic and natural crosslinking agents. Hydrogels that utilize synthetic crosslinking agents have advantages, such as adjustable mechanical properties and easy control of the chemical composition. However, hydrogels that use natural crosslinking agents have better biocompatibility and less latent toxic effect.
  • 7.0K
  • 28 Sep 2022
Topic Review
Hazard
A hazard is an agent which has the potential to cause harm to a vulnerable target. The terms "hazard" and "risk" are often used interchangeably. However, in terms of risk assessment, they are two very distinct terms. A hazard is any agent that can cause harm or damage to humans, property, or the environment. Risk is defined as the probability that exposure to a hazard will lead to a negative consequence, or more simply, a hazard poses no risk if there is no exposure to that hazard. Hazards can be dormant or potential, with only a theoretical probability of harm. An event that is caused by interaction with a hazard is called an incident. The likely severity of the undesirable consequences of an incident associated with a hazard, combined with the probability of this occurring, constitute the associated risk. If there is no possibility of a hazard contributing towards an incident, there is no risk. Hazards can be classified as different types in several ways. One of these ways is by specifying the origin of the hazard. One key concept in identifying a hazard is the presence of stored energy that, when released, can cause damage. Stored energy can occur in many forms: chemical, mechanical, thermal, radioactive, electrical, etc. Another class of hazard does not involve release of stored energy, rather it involves the presence of hazardous situations. Examples include confined or limited egress spaces, oxygen-depleted atmospheres, awkward positions, repetitive motions, low-hanging or protruding objects, etc. Hazards may also be classified as natural, anthropogenic, or technological. They may also be classified as health or safety hazards, by the populations that may be affected, and the severity of the associated risk. In most cases a hazard may affect a range of targets, and have little or no effect on others. Identification of hazards assumes that the potential targets are defined, and is the first step in performing a risk assessment.
  • 6.9K
  • 26 Oct 2022
Topic Review
Soaps and Syndets in Skin Cleansing
Skin cleansers generally come in one of two types: soap-based and synthetic detergents, or syndets. While the latter can effectively maintain the native skin structure, function and integrity, the former tends to negatively affect the skin by causing barrier disruption, lipid dissolution and pH alteration. Despite this, soap is still often preferred, possibly due to the negative connotations around anything that is not perceived as ‘natural’. 
  • 6.9K
  • 21 Apr 2022
Topic Review
Drying Methods of Probiotic Formulations
Preparations containing probiotic strains of bacteria have a beneficial effect on human and animal health. Concentrated probiotic bacteria used in animal nutrition and consumed by humans most commonly occur in the form of dried biomass. The benefits of probiotics translate into an increased interest in techniques for the preservation of microorganisms. 
  • 6.9K
  • 18 Aug 2022
Topic Review
Taxonomy
In biology, taxonomy (from grc τάξις (taxis) 'arrangement', and -νομία (-nomia) 'method') is the scientific study of naming, defining (circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain, kingdom, phylum (division is sometimes used in botany in place of phylum), class, order, family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, as he developed a ranked system known as Linnaean taxonomy for categorizing organisms and binomial nomenclature for naming organisms. With advances in the theory, data and analytical technology of biological systematics, the Linnaean system has transformed into a system of modern biological classification intended to reflect the evolutionary relationships among organisms, both living and extinct.
  • 6.9K
  • 05 Dec 2022
Topic Review
Urban Legend
An urban legend, urban myth, urban tale, or contemporary legend is a genre of folklore comprising stories circulated as true, especially as having happened to a friend or family member, often with horrifying or humorous elements. These legends can be entertainment, but often concern mysterious peril or troubling events, such as disappearances and strange objects. They may also be confirmation of moral standards, or reflect prejudices, or be a way to make sense of societal anxieties. Urban legends are most often circulated orally, but can be spread by any media, including newspapers, e-mail and social media. Some urban legends have passed through the years with only minor changes to suit regional variations. Recent legends tend to reflect modern circumstances: for instance, the common legend of a person being ambushed and anesthetized, only to wake up and realize that they are now missing a kidney that was supposedly surgically removed for transplantation.
  • 6.9K
  • 04 Oct 2022
Topic Review
Hypertensive Nephropathy
Hypertension is one of the most common risk factors for developing chronic cardiovascular diseases, including hypertensive nephropathy. Within the glomerulus, hypertension causes damage and activation of mesangial cells (MCs), eliciting the production of large amounts of vasoactive and proinflammatory agents. Accordingly, the activation of AT1 receptors by the vasoactive molecule angiotensin II (AngII) contributes to the pathogenesis of renal damage, which is mediated mostly by the dysfunction of intracellular Ca2+ ([Ca2+]i) signaling. Similarly, inflammation entails complex processes, where [Ca2+]i also play crucial roles. Deregulation of this second messenger increases cell damage and promotes fibrosis, reduces renal blood flow, and impairs the glomerular filtration barrier. In vertebrates, [Ca2+]i signaling depends, in part, on the activity of two families of large-pore channels: hemichannels and pannexons. Interestingly, the opening of these channels depends on [Ca2+]i signaling. 
  • 6.9K
  • 23 Dec 2022
Topic Review
Aquaporin Inhibitors
Aquaporins (AQPs) are water channel proteins that are essential to life, being expressed in all kingdoms. In humans, there are 13 AQPs, at least one of which is found in every organ system. The structural biology of the AQP family is well-established and many functions for AQPs have been reported in health and disease. AQP expression is linked to numerous pathologies including tumor metastasis, fluid dysregulation, and traumatic injury. The targeted modulation of AQPs therefore presents an opportunity to develop novel treatments for diverse conditions. Various techniques such as video microscopy, light scattering and fluorescence quenching have been used to test putative AQP inhibitors in both AQP-expressing mammalian cells and heterologous expression systems. The inherent variability within these methods has caused discrepancy and many molecules that are inhibitory in one experimental system (such as tetraethylammonium, acetazolamide, and anti-epileptic drugs) have no activity in others. Some heavy metal ions (that would not be suitable for therapeutic use) and the compound, TGN-020, have been shown to inhibit some AQPs. Clinical trials for neuromyelitis optica treatments using anti-AQP4 IgG are in progress. However, these antibodies have no effect on water transport. More research to standardize high-throughput assays is required to identify AQP modulators for which there is an urgent and unmet clinical need.
  • 6.9K
  • 06 Sep 2021
Topic Review
Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (P-ANCA)
Perinuclear anti-neutrophilic cytoplasmic antibodies (P-ANCA) recognize heterogeneous antigens, including myeloperoxidase (MPO), lactoferrin, elastase, cathepsin-G and bactericidal/permeability-increasing protein. Although P-ANCA have diagnostic utility in vasculitides, they may also be found in patients with various other systemic autoimmune rheumatic diseases (SARDs). Nevertheless, the clinical significance and the targets recognized by P-ANCA in such patients remain unclear. For this purpose, herein we investigated the occurrence of ANCA-related antigenic specificities in 82 P-ANCA-positive sera by multiplex ELISA, as well as their association with other autoantibodies. The P-ANCA-positive sera corresponded to patients with vasculitides (n = 24), systemic lupus erythematosus (n = 28), antiphospholipid syndrome (n = 5), Sjögren’s syndrome (n = 7), rheumatoid arthritis (n = 3), systemic scleroderma (n = 1), sarcoidosis (n = 1) and Hashimoto′s thyroiditis (n = 13). In most P-ANCA-positive patients studied (51/82, 62.3%), these autoantibodies occurred in high titers (>1:160). The analysis of P-ANCA-positive sera revealed reactivity to MPO in only 50% of patients with vasculitides, whereas it was infrequent in the other disease groups studied. Reactivity to other P-ANCA-related autoantigens was also rarely detected. Our findings support that high P-ANCA titers occur in SARD. The P-ANCA-positive staining pattern is associated with MPO specificity in vasculitides, while in other autoimmune diseases, it mostly involves unknown autoantigens. 
  • 6.9K
  • 27 Aug 2021
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