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Topic Review
Dynamic Positioning
Dynamic positioning (DP) is a computer-controlled system to automatically maintain a vessel's position and heading by using its own propellers and thrusters. Position reference sensors, combined with wind sensors, motion sensors and gyrocompasses, provide information to the computer pertaining to the vessel's position and the magnitude and direction of environmental forces affecting its position. Examples of vessel types that employ DP include, but are not limited to, ships and semi-submersible mobile offshore drilling units (MODU), oceanographic research vessels, cable layer ships and cruise ships. The computer program contains a mathematical model of the vessel that includes information pertaining to the wind and current drag of the vessel and the location of the thrusters. This knowledge, combined with the sensor information, allows the computer to calculate the required steering angle and thruster output for each thruster. This allows operations at sea where mooring or anchoring is not feasible due to deep water, congestion on the sea bottom (pipelines, templates) or other problems. Dynamic positioning may either be absolute in that the position is locked to a fixed point over the bottom, or relative to a moving object like another ship or an underwater vehicle. One may also position the ship at a favorable angle towards wind, waves and current, called weathervaning. Dynamic positioning is used by much of the offshore oil industry, for example in the North Sea, Persian Gulf, Gulf of Mexico, West Africa, and off the coast of Brazil . There are currently more than 1800 DP ships.
  • 3.0K
  • 04 Nov 2022
Topic Review
Mode (Computer Interface)
In user interface design, a mode is a distinct setting within a computer program or any physical machine interface, in which the same user input will produce perceived results different to those that it would in other settings. The best-known modal interface components are probably the Caps lock and Insert keys on the standard computer keyboard, both of which put the user's typing into a different mode after being pressed, then return it to the regular mode after being re-pressed. An interface that uses no modes is known as a modeless interface. Modeless interfaces avoid mode errors by making it impossible for the user to commit them.
  • 3.0K
  • 16 Nov 2022
Topic Review
Atmospheric Turbulence
The foundation of any smart city requires an innovative and robust communication infrastructure. Many research communities envision free-space optical communication (FSO) as a promising backbone technology for the services and applications provided by such cities. However, the channel through which the FSO signal travels is the atmosphere. Therefore, the FSO performance is limited by the local weather conditions. The variation in meteorological variables leads to variations of the refractive index along the transmission path. These index inhomogeneities (i.e., atmospheric turbulence) can significantly degrade the performance of FSO systems.  The effect of atmospheric turbulence on FSO systems is a considerable challenge. Such turbulence can produce beam scintillation, spreading, and wandering, resulting in a significant reduction in BER performance and the inability to use the communication link.
  • 3.0K
  • 24 Apr 2022
Topic Review
T-Cell Receptor Repertoire Sequencing and Its Applications
The immune system is a dynamic feature of each individual and a footprint of our unique internal and external exposures. Indeed, the type and level of exposure to physical and biological agents shape the development and behavior of this complex and diffuse system. Many pathological conditions depend on how our immune system responds or does not respond to a pathogen or a disease or on how the regulation of immunity is altered by the disease itself. T-cells are important players in adaptive immunity and, together with B-cells, define specificity and monitor the internal and external signals that our organism perceives through its specific receptors, TCRs and BCRs, respectively. Today, high-throughput sequencing (HTS) applied to the TCR repertoire has opened a window of opportunity to disclose T-cell repertoire development and behavior down to the clonal level. Although TCR repertoire sequencing is easily accessible today, it is important to deeply understand the available technologies for choosing the best fit for the specific experimental needs and questions. Here, an updated overview of TCR repertoire sequencing strategies, providers and applications to infectious diseases and cancer to guide researchers’ choice through the multitude of available options is provided. The possibility of extending the TCR repertoire to HLA characterization will be of pivotal importance in the near future to understand how specific HLA genes shape T-cell responses in different pathological contexts and will add a level of comprehension that was unthinkable just a few years ago.
  • 3.0K
  • 24 Aug 2022
Topic Review
Intracellular Organelles
Viruses have evolved different strategies to hijack subcellular organelles during their life cycle to produce robust infectious progeny. Successful viral reproduction requires the precise assembly of progeny virions from viral genomes, structural proteins, and membrane components. Such spatial and temporal separation of assembly reactions depends on accurate coordination among intracellular compartmentalization in multiple organelles. Virus trigger the rearrangement and morphology remodeling of intracellular organelles, including the quality control of intracellular organelles, the hijacking of the modified organelle membranes, morphology remodeling for viral replication, and degradation of intracellular organelles by virus-triggered selective autophagy.
  • 3.0K
  • 27 Oct 2020
Topic Review
Cat Body-type Mutation
Cats, like all living organisms, occasionally have mutations that affect their body type. Sometimes, these cat body-type mutations are striking enough that humans select for and perpetuate them. This is not always in the best interests of the cat, as many of these mutations are harmful; some are even lethal in their homozygous form. This article gives a selection of cat body type mutant alleles and the associated mutations with a brief description.
  • 3.0K
  • 29 Sep 2022
Topic Review
Yellow Supergiant Star
A yellow supergiant (YSG) is a star, generally of spectral type F or G, having a supergiant luminosity class (e.g. Ia or Ib). They are stars that have evolved away from the main sequence, expanding and becoming more luminous. Yellow supergiants are smaller than red supergiants; naked eye examples include Polaris. Many of them are variable stars, mostly pulsating Cepheids such as δ Cephei itself.
  • 3.0K
  • 03 Nov 2022
Topic Review
Falkland Islands Wolf
The Falkland Islands Wolf, scientifically known as Dusicyon australis, was a unique canid species that once inhabited the Falkland Islands in the South Atlantic Ocean. Also known as the Warrah, it represented the only native land mammal on the islands and is believed to have been isolated for thousands of years, evolving in the absence of large predators. Unfortunately, the Falkland Islands Wolf became extinct in the 19th century, marking the end of a distinct evolutionary lineage.
  • 3.0K
  • 08 Feb 2024
Topic Review
Muon Radiography with Nuclear Emulsion Detectors
The paper presents the test experiment to investigate one of UNESCO’s world heritage objects, an archaeological site in the Naryn-Kala citadel (Derbent, Republic of Dagestan, RF) hidden under the ground surface. The function of the site could be revealed by the muon radiography studies. Several nuclear emulsion detectors were exposed for two months inside the site at a depth about 10 m from the modern surface. The use of nuclear emulsions as probing radiation detectors combined with the potential of modern image analysis methods provides for a uniquely high resolution capacity of recording instrumentation and 3D reconstruction of the internal structure of the investigated object. Here we present short descrption of muon radiography method, the test experiment, data analysis details and the first results.
  • 3.0K
  • 30 Oct 2020
Topic Review
Implications of Sphingolipid Metabolites in Kidney Diseases
Sphingolipids (SLs) are lipids with complex structures which were named after their sphinx-like structure by Thudichium in 1870. Lipids are major components of membranes in all eukaryotic cells determining the structural and functional integrity of cells. SLs are one of the important structural components of plasma membranes in all eukaryotes, but they also act as bioactive signaling molecules with numerous cellular physiological functions that include cell adhesion, cell proliferation, cell migration, inflammatory response and apoptosis. Sphingolipids, which act as a bioactive signaling molecules, are involved in several cellular processes such as cell survival, proliferation, migration and apoptosis. An imbalance in the levels of sphingolipids can be lethal to cells. Abnormalities in the levels of sphingolipids are associated with several human diseases including kidney diseases. Several studies demonstrate that sphingolipids play an important role in maintaining proper renal function. Sphingolipids can alter the glomerular filtration barrier by affecting the functioning of podocytes, which are key cellular components of the glomerular filtration barrier. 
  • 3.0K
  • 29 Apr 2022
Topic Review
Application of Graphene in Electronic Devices
Graphene achieved a peerless level among nanomaterials in terms of its application in electronic devices, owing to its fascinating and novel properties. Its large surface area and high electrical conductivity combine to create high-power batteries. In addition, because of its high optical transmittance, low sheet resistance, and the possibility of transferring it onto plastic substrates, graphene is also employed as a replacement for indium tin oxide (ITO) in making electrodes for touch screens. Moreover, it was observed that graphene enhances the performance of transparent flexible electronic modules due to its higher mobility, minimal light absorbance, and superior mechanical properties. Graphene is even considered a potential substitute for the post-Si electronics era, where a high-performance graphene-based field-effect transistor (GFET) can be fabricated to detect the lethal SARS-CoV-2. Hence, graphene incorporation in electronic devices can facilitate immense device structure/performance advancements.
  • 3.0K
  • 18 Oct 2022
Topic Review
Cholesterol
Cholesterol, the most important sterol in mammals, helps maintain plasma membrane fluidity and is a precursor of bile acids, oxysterols, and steroid hormones. Cholesterol in the body is obtained from the diet or can be de novo synthetized. Cholesterol homeostasis is mainly regulated by the liver, where cholesterol is packed in lipoproteins for transport through a tightly regulated process. Changes in circulating lipoprotein cholesterol levels lead to atherosclerosis development, which is initiated by an accumulation of modified lipoproteins in the subendothelial space; this induces significant changes in immune cell differentiation and function. In this entry, we describe the main regulatory pathways and mechanisms of cholesterol metabolism.
  • 3.0K
  • 17 Jan 2022
Topic Review
Biomass Feedstocks Thermochemical Conversion Processes
An effective analytical technique for biomass characterisation is inevitable for biomass utilisation in energy production. To improve biomass processing, various thermal conversion methods such as torrefaction, pyrolysis, combustion, hydrothermal liquefaction, and gasification have been widely used to improve biomass processing. Thermogravimetric analysers (TG) and gas chromatography (GC) are among the most fundamental analytical techniques utilised in biomass thermal analysis. Thus, GC and TG, in combination with MS, FTIR, or two-dimensional analysis, were used to examine the key parameters of biomass feedstock and increase the productivity of energy crops. We can also determine the optimal ratio for combining two separate biomass or coals during co-pyrolysis and co-gasification to achieve the best synergetic relationship. 
  • 3.0K
  • 18 Sep 2021
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
Drone Architecture for Crowd Monitoring and Analysis
Crowd monitoring and analysis is an important evolving applications of unmanned aerial vehicle or drones. From preventing stampede in high concentration crowds to estimating crowd density and to surveilling crowd movements, crowd monitoring and analysis have long been employed in the past by authorities and regulatory bodies to tackle challenges posed by large crowds.
  • 3.0K
  • 03 Mar 2022
Topic Review
1860 Oxford Evolution Debate
The 1860 Oxford evolution debate took place at the Oxford University Museum in Oxford, England , on 30 June 1860, seven months after the publication of Charles Darwin's On the Origin of Species. Several prominent British scientists and philosophers participated, including Thomas Henry Huxley, Bishop Samuel Wilberforce, Benjamin Brodie, Joseph Dalton Hooker and Robert FitzRoy. The debate is best remembered today for a heated exchange in which Wilberforce supposedly asked Huxley whether it was through his grandfather or his grandmother that he claimed his descent from a monkey. Huxley is said to have replied that he would not be ashamed to have a monkey for his ancestor, but he would be ashamed to be connected with a man who used his great gifts to obscure the truth. One eyewitness suggests that Wilberforce's question to Huxley may have been "whether, in the vast shaky state of the law of development, as laid down by Darwin, any one can be so enamoured of this so-called law, or hypothesis, as to go into jubilation for his great great grandfather having been an ape or a gorilla?", whereas another suggests he may have said that "it was of little consequence to himself whether or not his grandfather might be called a monkey or not." The encounter is often known as the Huxley–Wilberforce debate or the Wilberforce–Huxley debate, although this description is somewhat misleading. Rather than being a formal debate between the two, it was actually an animated discussion that occurred after the presentation of a paper by John William Draper of New York University, on the intellectual development of Europe with relation to Darwin's theory (one of a number of scientific papers presented during the week as part of the British Association's annual meeting). Although Huxley and Wilberforce were not the only participants in the discussion, they were reported to be the two dominant parties. No verbatim account of the debate exists, and there is considerable uncertainty regarding what Huxley and Wilberforce actually said.
  • 3.0K
  • 18 Oct 2022
Topic Review
Single Event Upset
A single event upset (SEU) is a change of state caused by one single ionizing particle (ions, electrons, photons...) striking a sensitive node in a micro-electronic device, such as in a microprocessor, semiconductor memory, or power transistors. The state change is a result of the free charge created by ionization in or close to an important node of a logic element (e.g. memory "bit"). The error in device output or operation caused as a result of the strike is called an SEU or a soft error. The SEU itself is not considered permanently damaging to the transistor's or circuits' functionality unlike the case of single event latchup (SEL), single event gate rupture (SEGR), or single event burnout (SEB). These are all examples of a general class of radiation effects in electronic devices called single event effects (SEE).
  • 3.0K
  • 24 Oct 2022
Topic Review
Phishing Email Detection Model Using Deep Learning
Email phishing is a widespread cyber threat that can result in the theft of sensitive information and financial loss. It uses malicious emails to trick recipients into providing sensitive information or transferring money, often by disguising themselves as legitimate organizations or individuals. As technology advances and attackers become more sophisticated, the problem of email phishing becomes increasingly challenging to detect and prevent.
  • 3.0K
  • 19 Oct 2023
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
Metamaterials
Metamaterials are amongst the advanced materials made up initially with metal structures. However, there is a huge ongoing work on dielectric metasurfaces and metamaterials with the aim of replacing metal structures with dielectric ones in order to reduce the electromagnetic losses.
  • 3.0K
  • 31 Mar 2022
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