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Topic Review
North Magnetic Pole
The North Magnetic Pole is a wandering point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the Geographic North Pole and the Geomagnetic North Pole. The North Magnetic Pole moves over time according to magnetic changes and flux lobe elongation in the Earth's outer core. In 2001, it was determined by the Geological Survey of Canada to lie west of Ellesmere Island in northern Canada at 81°18′N 110°48′W / 81.3°N 110.8°W / 81.3; -110.8 (Magnetic North Pole 2001). It was situated at 83°06′N 117°48′W / 83.1°N 117.8°W / 83.1; -117.8 (Magnetic North Pole 2005 est) in 2005. In 2009, while still situated within the Canadian Arctic at 84°54′N 131°00′W / 84.9°N 131°W / 84.9; -131 (Magnetic North Pole 2009), it was moving toward Russia at between 55 and 60 km (34 and 37 mi) per year. As of 2019, the pole is projected to have moved beyond the Canadian Arctic to 86°26′52.8″N 175°20′45.06″E / 86.448°N 175.34585°E / 86.448; 175.34585 (Magnetic North Pole 2019 est). Its southern hemisphere counterpart is the South Magnetic Pole. Since Earth's magnetic field is not exactly symmetrical, the North and South Magnetic Poles are not antipodal, meaning that a straight line drawn from one to the other does not pass through the geometric center of Earth. Earth's North and South Magnetic Poles are also known as magnetic dip poles, with reference to the vertical "dip" of the magnetic field lines at those points.
  • 2.8K
  • 17 Oct 2022
Topic Review
Polyurethanes in Biomedicine
Due to their mechanical properties, ranging from flexible to hard materials, polyurethanes (PUs) have been widely used in many industrial and biomedical applications. PU characteristics, along with their biocompatibility, make them successful biomaterials in short and medium time applications.  The most important biomedical applications of PUs include antibacterial surfaces and catheters, blood oxygenators, dialysis devices, stents, cardiac valves, vascular prostheses, bioadhesives/surgical dressings/pressure sensitive adhesives, drug delivery systems, tissue engineering scaffolds and electrospinning, nerve generation, pacemaker lead insulation and coatings for breast implants. The diversity of polyurethane properties due to the ease of bulk and surface modification plays a vital role in their applications. 
  • 2.8K
  • 28 Oct 2020
Topic Review
Gathas
The Gathas (/ˈɡɑːtəz, -tɑːz/) are 17 Avestan hymns believed to have been composed by Zarathushtra (Zoroaster) himself. They form the core of the Zoroastrian liturgy (the Yasna). They are arranged in five different modes or metres. The Avestan term gāθā (𐬔𐬁𐬚𐬁 "hymn", but also "mode, metre") is cognate with Sanskrit gāthā (गाथा), both from the Proto-Indo-Iranian word *gaHtʰáH, from the root *gaH- "to sing".
  • 2.8K
  • 24 Oct 2022
Topic Review
Locative Media
Locative media or location-based media (LBM) are media of communication functionally bound to a location. The physical implementation of locative media, however, is not bound to the same location to which the content refers. Location-based media delivers multimedia and other content directly to the user of a mobile device dependent upon their location. Location information determined by means such as mobile phone tracking and other emerging real-time locating system technologies like Wi-Fi or RFID can be used to customize media content presented on the device. Locative media are digital media applied to real places and thus triggering real social interactions. While mobile technologies such as the Global Positioning System (GPS), laptop computers and mobile phones enable locative media, they are not the goal for the development of projects in this field.
  • 2.8K
  • 24 Oct 2022
Topic Review
Escherichia coli Shiga Toxins
Escherichia coli (EHEC) and Shigella dysenteriae serotype 1 are enterohemorrhagic bacteria that induce hemorrhagic colitis. This, in turn, may result in potentially lethal complications, such as hemolytic uremic syndrome (HUS), which is characterized by thrombocytopenia, acute renal failure, and neurological abnormalities. Both species of bacteria produce Shiga toxins (Stxs), a phage-encoded exotoxin inhibiting protein synthesis in host cells that are primarily responsible for bacterial virulence.
  • 2.8K
  • 23 Jun 2021
Topic Review
Melissa officinalis
Melissa officinalis is a medicinal plant rich in biologically active compounds which is used worldwide for its therapeutic effects. Chemical studies on its composition have shown that it contains mainly flavonoids, terpenoids, phenolic acids, tannins, and essential oil. The main active constituents of Melissa officinalis are volatile compounds (geranial, neral, citronellal and geraniol), triterpenes (ursolic acid and oleanolic acid), phenolic acids (rosmarinic acid, caffeic acid and chlorogenic acid), and flavonoids (quercetin, rhamnocitrin, and luteolin). 
  • 2.8K
  • 06 Apr 2022
Topic Review
Alcohol Belts of Europe
The alcohol belts of Europe divide Europe by their traditional alcoholic beverages: beer, wine, or spirits. They do not necessarily correspond with current drinking habits, as beer has become the most popular alcoholic drink world-wide. The definitions of these belts are not completely objective.
  • 2.8K
  • 25 Oct 2022
Topic Review
Targeted Killing
Targeted killing is defined as a form of murder or assassination carried out by governments. Some analysts believe that it is a modern euphemism for the assassination of a prominent individual by a state organization or institution outside a judicial procedure or a battlefield. Since the late 20th century, the legal status of targeted killing has become a subject of contention within and between various nations. Historically, at least since the mid-eighteenth century, Western thinking has generally considered the use of assassination as a tool of statecraft to be illegal. Some academics, military personnel and officials describe targeted killing as legitimate within the context of self-defense, when employed against terrorists or combatants engaged in asymmetrical warfare. They argue that drones are more humane and more accurate than manned vehicles, and that targeted or "named killings" do not occur in any context other than a declared state of war. Some twenty-six members of United States Congress, with academics such as Gregory Johnsen and Charles Schmitz, media figures (Jeremy Scahill, Glenn Greenwald, James Traub), civil rights groups (i.e. the American Civil Liberties Union) and ex-CIA station chief in Islamabad, Robert Grenier, have criticized targeted killings as a form of extrajudicial killings, which may be illegal under both United States and international law. According to statistical analyses provided by Reprieve, nine children have been killed for every adult the United States has tried to assassinate, and, in its numerous failed attempts to kill Ayman al-Zawahri, the CIA killed 76 children and 29 adult bystanders. Scholars are also divided as to whether targeted killings are an effective counterterrorism strategy.
  • 2.8K
  • 25 Nov 2022
Topic Review
SiC Trench MOSFETs’ Reliability under Short-Circuit Conditions
MOSFETs exhibit different failure modes at different DC bus voltages.  For double trench SiC MOSFETs, the failure modes are gate fault at lower DC bus voltage and thermal runaway at higher DC bus voltage, while the failure modes for asymmetric trench SiC MOSFETs are soft failure and thermal runaway, respectively.  The short-circuit withstand time (SCWT) of the asymmetric trench MOSFET is higher than that of the double trench MOSFET.  The thermal and mechanical stresses inside the device during short-circuit test are simulated to explore the failure mechanism and reveal the impact of device structure on device reliability.  Finally, a post-failure analysis was performed to verify the root cause of the equipment failure.  
  • 2.8K
  • 28 Mar 2022
Topic Review
Physiotherapy treatment for Dysphagia
Dysphagia (DP) is a condition characterised by the loss of swallowing function, due to the alteration of the oral route and of the pharyngeal and esopharyngeal phases, hindering or impeding the passage of the alimentary bolus from the mouth to the stomach. DP affects 13% of people over 65 years of age and approximately 33% of people over 80 years of age, although it has a prevalence of 55% after a stroke. The most common complications associated with this disorder are: suffocation, aspiration pneumonia, malnutrition and decreased physical activity; these must be addressed with special care and individually.
  • 2.8K
  • 27 Oct 2020
Topic Review
Triarylmethyl Radical-Based High-Efficiency OLED
Perchlorotrityl radical (PTM), tris (2,4,6-trichlorophenyl) methyl radical (TTM), (3,5-dichloro-4-pyridyl) bis (2,4,6 trichlorophenyl) methyl radical (PyBTM), (N-carbazolyl) bis (2,4,6-trichlorophenyl) methyl radical (CzBTM), and their derivatives are stable organic radicals that exhibit light emissions at room temperature. Since these triarylmethyl radicals have an unpaired electron, their electron spins at the lowest excited state and ground state are both doublets, and the transition from the lowest excited state to the ground state does not pose the problem of a spin-forbidden reaction. When used as OLED layers, these triarylmethyl radicals exhibit unique light-emitting properties, which can increase the theoretical upper limit of the OLED’s internal quantum efficiency (IQE) to 100%.
  • 2.8K
  • 15 Apr 2022
Topic Review
Neolithic Subpluvial
The Neolithic Subpluvial, or the Holocene Wet Phase, was an extended period (from about 7500–7000 BCE to about 3500–3000 BCE) of wet and rainy conditions in the climate history of northern Africa. It was both preceded and followed by much drier periods. The Neolithic Subpluvial was the most recent of a number of periods of "Wet Sahara" or "Green Sahara", during which the Sahara region was much moister and supported a richer biota and human population than the present-day desert.
  • 2.8K
  • 24 Oct 2022
Topic Review
Sagittarius
Sagittarius, often referred to as "the Archer," is a prominent constellation in the southern celestial hemisphere, renowned for its association with Greek mythology and the mythical centaur Chiron. Positioned along the Milky Way, Sagittarius hosts a wealth of celestial wonders, including the galactic center and numerous star clusters.
  • 2.8K
  • 15 Mar 2024
Topic Review
Application of the IoT in Disaster Risk Management
Taiwan is in a hazard-exposed area where people often suffer through typhoons, earthquakes, and landslides, and must face the challenges of environmental and climate changes in ongoing and future developments. Taiwan has implemented an integrated and interdisciplinary project, which is titled Civil IoT Taiwan, for better disaster risk management and risk communication with all stakeholders by cooperating closely with authorities, scientists, and industry. 
  • 2.8K
  • 30 Dec 2021
Topic Review
Intra-Organismal Distribution of Tetrodotoxin in Tetrodotoxin-Bearing Animals
Tetrodotoxin (TTX), one of the deadliest natural toxins, has attracted the interest of researchers from various fields for decades. This non-protein, weakly basic, heat-resistant low-molecular-weight toxin selectively blocks voltage-gated sodium channels along the muscle and nerve cells.
  • 2.8K
  • 08 Nov 2022
Topic Review
Amsterdam (VOC Ship)
The Amsterdam (Dutch pronunciation: [ˌɑmstərˈdɑm] (listen)) was an 18th-century cargo ship of the Dutch East India Company (Dutch: Vereenigde Oost-Indische Compagnie; VOC). The VOC was established in 1602. The ship started its maiden voyage from Texel to Batavia on 8 January 1749, but was wrecked in a storm on the English Channel on 26 January 1749. The shipwreck was discovered in 1969 in the bay of Bulverhythe, near Hastings on the English south coast, and is sometimes visible during low tides. The wreck site is protected under the Protection of Wrecks Act since 1974. Some of the findings from the site are in The Shipwreck Museum in Hastings. A replica of the ship is on display in Amsterdam.
  • 2.8K
  • 01 Dec 2022
Topic Review
Industrial IoT for Mining Industry
The Industrial Internet of Things (IIoT) has the potential to improve the production and business processes by enabling the extraction of valuable information from industrial processes. The mining industry, however, is rather traditional and somewhat slow to change due to infrastructural limitations in communication, data management, storage, and exchange of information. Most research efforts so far on applying IIoT in the mining industry focus on specific concerns such as ventilation monitoring, accident analysis, fleet and personnel management, tailing dam monitoring, and pre-alarm system while an overall IIoT architecture suitable for the general conditions in the mining industry is still missing.
  • 2.8K
  • 16 Jun 2021
Topic Review
TNF
TNF is a gene that plays an essential role in the body, it affects both immune response and inflammation. The gene encodes a protein called tumour necrosis factor alpha (TNFα) [1].
  • 2.8K
  • 05 Nov 2020
Topic Review
Transparent Electrode Materials
The nonrenewable nature of fossil energy has led to a gradual decrease in reserves. Meanwhile, as society becomes increasingly aware of the severe pollution caused by fossil energy, the demand for clean energy, such as solar energy, is rising. Moreover, in recent years, electronic devices with screens, such as mobile phones and computers, have had increasingly higher requirements for light transmittance. Whether in solar cells or in the display elements of electronic devices, transparent conductive films directly affect the performance of these devices as a cover layer. In this context, the development of transparent electrodes with low sheet resistance and high light transmittance has become one of the most urgent issues in related fields. At the same time, conventional electrodes can no longer meet the needs of some of the current flexible devices. Because of the high sheet resistance, poor light transmittance, and poor bending stability of the conventional tin-doped indium tin oxide conductive film and fluorine-doped tin oxide transparent conductive glass, there is a need to find alternatives with better performance. In this entry, the progress of research on transparent electrode materials with sandwich structures and their advantages is reviewed according to the classification of conductive materials to provide reference for research in related fields.
  • 2.8K
  • 09 Aug 2021
Topic Review
Magnetoencephalography
Magnetoencephalography (MEG) is a functional brain imaging technique that measures magnetic flux on the surface of the head associated with underlying neuronal electrical dipoles.
  • 2.8K
  • 08 Mar 2021
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