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Topic Review
Electric Vehicle Charger Cybersecurity Vulnerabilities
Worldwide growth in electric vehicle use is prompting new installations of private and public electric vehicle supply equipment (EVSE). EVSE devices support the electrification of the transportation industry but also represent a linchpin for power systems and transportation infrastructures. Cybersecurity researchers have identified several vulnerabilities that exist in EVSE devices, communications to electric vehicles (EVs), and upstream services, such as EVSE vendor cloud services, third-party systems, and grid operators. 
  • 6.0K
  • 02 Jun 2022
Topic Review
Permanent Magnet Linear Synchronous Motor
In high-end testing and manufacturing equipment, a trend exists whereby the traditional servo feed system with a ball screw and rotary motor will gradually be replaced by a direct drive system. The precision motion system driven by a permanent magnet linear synchronous motor (PMLSM) offers several advantages, including high speed, high acceleration, and high positioning accuracy. However, the operating precision of the feed device will be affected by the PMLSM robustness to nonlinear and uncertain disturbances, such as cogging force, friction, thermal effects, residual vibration, and load disturbance.
  • 6.0K
  • 29 Apr 2021
Topic Review
Emirate of Ras Al Khaimah
Ras Al Khaimah (RAK) (Arabic: رَأْس ٱلْخَيْمَة; IPA: [raʔs lˈxajma]), also spelled as Ras al Khaimah or Ras al-Khaimah, is one of the seven emirates that make up the United Arab Emirates (UAE). The city of Ras Al Khaimah, sometimes simply abbreviated to RAK City, is the capital of the emirate and home to most of the emirate's residents. It is linked to the medieval trading port of Julfar.[lower-alpha 1] Its name in English means "top of the tent". The emirate borders Oman's exclave of Musandam, and occupies part of the same peninsula. It covers an area of 2,486 km2 (960 sq mi) and has 64 km (40 mi) of beach coastline. As of 2015, the emirate had a population of about 345,000, of which about 31% were Emirati citizens. RAK city has two main areas - the Old Town and Nakheel - on either side of a creek that is home to mangroves and is framed by the North-Western Hajar Mountains. The emirate also consists of several villages and new gated residential developments, such as Al Hamra Village and Mina Al Arab. The emirate is served by Ras Al Khaimah International Airport. Its geography consists of a northern part (where Ras Al Khaimah City and most towns are situated) and a large southerly inland exclave (near the Dubai exclave of Hatta), and a few small islands in the Persian Gulf. Ras Al Khaimah has the most fertile soil in the country, due to a larger share of rainfall and underground water streams from the Hajar.
  • 6.0K
  • 10 Oct 2022
Topic Review
Old Azeri Language
Old Azeri (Persian: آذری‌ باستان‎), also referred to as Azeri or Azari (Persian: آذری‎ Āḏarī [ɑːzæri]), is the extinct Iranian language that was once spoken in Azerbaijan (historic Azerbaijan, also known as Iranian Azerbaijan) before the Turkification of the Azeris. Some linguists believe the southern Tati varieties of Iranian Azerbaijan around Takestan such as the Harzandi and Karingani dialects to be remnants of Azeri. In addition, Old Azeri is known to have strong affinities with Talysh. Azeri was the dominant language in Azerbaijan before it was replaced by Azerbaijani, which is a Turkic language.
  • 5.9K
  • 30 Nov 2022
Topic Review
Nanodiamonds Synthesis Techniques
The "state-of-the-art" of the nanodiamonds synthesis techniques is reviewed with emphasis on the more recent one involving pulsed laser ablation. Production of NV centers inside the nanodiamonds and  post-production cleaning processes to remove residual graphite layers are also described.
  • 5.9K
  • 27 Oct 2020
Topic Review
Amygdala
The amygdala is one of the areas in the brain involved in the development of PTSD as the starting point for the process of activation of the hypothalamo–pituitary axis and the cascade of physiological responses to acute stress. An appropriate response to acute stress is a vital adaptive mechanism, but its prolongation causes various biopsychosocial (previously, psychosomatic) disorders. Chronic stress leads to higher expression of CRH/CRF in the CE and BLA, which has an anxiogenic effect.
  • 5.9K
  • 13 Jul 2021
Topic Review
Landsat 8 and Landsat 9
With the launch of Landsat 9 in September 2021, an optimal opportunity for in-flight cross-calibration occurred when Landsat 9 flew underneath Landsat 8 while being moved into its final orbit. Since the two instruments host nearly identical imaging systems, the underfly event offered ideal cross-calibration conditions. Using the underfly imagery collected by the instruments to estimate cross-calibration parameters for Landsat 9 for a calibration update scheduled at the end of the on-orbit initial verification (OIV) period was studied. Three types of uncertainty were considered: geometric, spectral, and angular (bidirectional reflectance distribution function—BRDF). Differences caused by geometric uncertainty were found to be negligible for this application. 
  • 5.9K
  • 01 Jun 2022
Topic Review
Compartmental Models in Epidemiology
Compartmental models are a very general modelling technique. They are often applied to the mathematical modelling of infectious diseases. The population is assigned to compartments with labels – for example, S, I, or R, (Susceptible, Infectious, or Recovered). People may progress between compartments. The order of the labels usually shows the flow patterns between the compartments; for example SEIS means susceptible, exposed, infectious, then susceptible again. The origin of such models is the early 20th century, with important works being that of Ross in 1916, Ross and Hudson in 1917, Kermack and McKendrick in 1927 and Kendall in 1956 The models are most often run with ordinary differential equations (which are deterministic), but can also be used with a stochastic (random) framework, which is more realistic but much more complicated to analyze. Models try to predict things such as how a disease spreads, or the total number infected, or the duration of an epidemic, and to estimate various epidemiological parameters such as the reproductive number. Such models can show how different public health interventions may affect the outcome of the epidemic, e.g., what the most efficient technique is for issuing a limited number of vaccines in a given population.
  • 5.9K
  • 02 Dec 2022
Topic Review
Reaction Mechanism of CO2 Methanation
The combustion of fossil fuels has led to a large amount of carbon dioxide emissions and increased greenhouse effect. Methanation of carbon dioxide can not only mitigate the greenhouse effect, but also utilize the hydrogen generated by renewable electricity such as wind, solar, tidal energy, and others, which could ameliorate the energy crisis to some extent. Highly efficient catalysts and processes are important to make CO2 methanation practical. Although noble metal catalysts exhibit higher catalytic activity and CH4 selectivity at low temperature, their large-scale industrial applications are limited by the high costs. Ni-based catalysts have attracted extensive attention due to their high activity, low cost, and abundance. At the same time, it is of great importance to study the mechanism of CO2 methanation on Ni-based catalysts in designing high-activity and stability catalysts.
  • 5.9K
  • 07 Mar 2022
Topic Review
History of Purgatory
The idea of purgatory has roots that date back into antiquity. A sort of proto-purgatory called the "celestial Hades" appears in the writings of Plato and Heraclides Ponticus and in many other pagan writers. This concept is distinguished from the Hades of the underworld described in the works of Homer and Hesiod. In contrast, the celestial Hades was understood as an intermediary place where souls spent an undetermined time after death before either moving on to a higher level of existence or being reincarnated back on earth. Its exact location varied from author to author. Heraclides of Pontus thought it was in the Milky Way; the Academicians, the Stoics, Cicero, Virgil, Plutarch, the Hermetical writings situated it between the Moon and the Earth or around the Moon; while Numenius and the Latin Neoplatonists thought it was located between the sphere of the fixed stars and the Earth. Perhaps under the influence of Hellenistic thought, we find another intermediate state entering Jewish religious thought in the last centuries B.C.E. In Maccabees we find the practice of prayer for the dead with a view to their after life purification a practice accepted by some Christians. The same practice appears in other traditions, such as the medieval Chinese Buddhist practice of making offerings on behalf of the dead, who are said to suffer numerous trials. Among other reasons, Catholic belief in purgatory is based on the practice of prayer for the dead. Descriptions and doctrine regarding purgatory developed over the centuries. Those who believe in purgatory interpret extra-biblical passages such as 2 Maccabees 12:41-46 (not accepted as Scripture by Protestants but recognized by Orthodox and Catholics), and biblical passages such as 2 Timothy 1:18, Matthew 12:32, Luke 16:19-16:26, Luke 23:43, 1 Corinthians 3:11-3:15 and Hebrews 12:29 as support for prayer for the dead, an active interim state for the dead prior to the resurrection, and purifying flames after death. The first Christians looked forward to the imminent return of Christ and did not develop detailed beliefs about the interim state. Gradually, Christians, especially in the West, took an interest in circumstances of the interim state between one's death and the future resurrection. Christians both East and West prayed for the dead in this interim state, although theologians in the East refrained from defining it. Augustine of Hippo distinguished between the purifying fire that saves and eternal consuming fire for the unrepentant. Gregory the Great established a connection between earthly penance and purification after death. All Soul's Day, established in the 10th century, turned popular attention to the condition of departed souls. The idea of Purgatory as a physical place (like heaven and hell) was "born" in the late 11th century. Medieval theologians concluded that the purgatorial punishments consisted of material fire. The Western formulation of purgatory proved to be a sticking point in the Great Schism between East and West. The Catholic Church believes that the living can help those whose purification from their sins is not yet completed not only by praying for them but also by gaining indulgences for them as an act of intercession. The later Middle Ages saw the growth of considerable abuses, such as the unrestricted sale of indulgences by professional "pardoners" sent to collect contributions to projects such as the rebuilding of St. Peter's Basilica in Rome. These abuses were one of the factors that led to the Protestant Reformation. Most Protestants rejected the idea of purgatory, as never clearly mentioned in Luther's canon of the Bible, which excludes the Deuterocanonical books. Modern Catholic theologians have softened the punitive aspects of purgatory and stress instead the willingness of the dead to undergo purification as preparation for the happiness of heaven The English Anglican scholar John Henry Newman argued, in a book that he wrote before becoming Catholic, that the essence of the doctrine on purgatory is locatable in ancient tradition, and that the core consistency of such beliefs are evidence that Christianity was "originally given to us from heaven".
  • 5.9K
  • 14 Nov 2022
Topic Review
ATtiny Microcontroller Comparison Chart
ATtiny (also known as TinyAVR) are a subfamily of the popular 8-bit AVR microcontrollers, which typically has fewer features, fewer I/O pins, and less memory than other AVR series chips. The first members of this family were released in 1999 by Atmel (later acquired by Microchip Technology in 2016).
  • 5.9K
  • 03 Nov 2022
Topic Review Peer Reviewed
Frederick II of Hohenstaufen (1208–1250)
Frederick II of Hohenstaufen, King of Sicily (1208–1250). Frederick II of Hohenstaufen was the second king of the Swabian dynasty to sit on the throne of Sicily. He was crowned in 1198, but, in consideration of his young age, he only ruled independently from 1208 to 1250 (the year of his death). He not only held the title of King of Sicily but also was the King of Germany (or of the Romans), the King of Jerusalem, and, above all, Emperor of the Holy Roman Empire. His most relevant and innovative iconographic representations were in Southern Italy. For this reason, we focus on the images in this geographical context. In particular, we have nine official (that is, those commissioned directly by him or his entourage) representations of him: the bull (in three main versions), the seal (in three main versions), five coins (four denari and one augustale), the statue of the Capua Gate, and the lost image of the imperial palace in Naples.
  • 5.9K
  • 13 Apr 2022
Topic Review
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are analogous, whereas homologous structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different traits. Convergent evolution is similar to parallel evolution, which occurs when two independent species evolve in the same direction and thus independently acquire similar characteristics; for instance, gliding frogs have evolved in parallel from multiple types of tree frog. Many instances of convergent evolution are known in plants, including the repeated development of C4 photosynthesis, seed dispersal by fleshy fruits adapted to be eaten by animals, and carnivory.
  • 5.9K
  • 24 Oct 2022
Topic Review
Environmental Protection and Sustainable Development in Madagascar
Located on the East coast of Africa, Madagascar is the world’s fourth-biggest island; Madagascar is host to 12,000 species of vascular plants (96% endemic). Over 90% of all its wildlife is found nowhere else on earth, and 5% of all of the earth’s biodiversity is found in Madagascar. A place where environmental degradation problems have created severe erosion and water quality problems. Despite its biological and cultural diversity, Madagascar is among the poorest countries in the world, with approximately 78% of the population living in extreme poverty with an average income of less than USD 2 per day, and more than three-quarters of the population in rural areas engaged in natural resources dependent livelihood activities. 
  • 5.9K
  • 07 Dec 2022
Topic Review
Football Goalkeeper Injuries
Knowledge and research about football goalkeeper (GK) injuries are scarce, which prevents the development of evidence-based injury prevention programs. Fortunately, progress is evident in injury prevention strategies in outfield football players. However, a GK fulfills a unique role, and an injured GK can substantially impact a team. Thus, there is a need to clarify and summarize current knowledge concerning football goalkeeper pain and injuries.
  • 5.9K
  • 31 May 2021
Topic Review
Smart City 4.0 Development
The concept of the Smart City emerged as an effect of the research into smart urban environments. The term ‘smart city’ is understood as a city having a certain intellectual ability, which refers to innovative sociotechnical and socioeconomic aspects of growth. It has six dimensions: a smart economy, smart mobility, smart environment, smart people, smart living, and smart governance. Smart Cities 4.0 remain hyper-connected, as they use technology, data and engagement of citizens, but they use it to achieve the objectives of sustainable development.
  • 5.9K
  • 21 Mar 2022
Topic Review
Lipid Oxidation in Food Systems
Lipids are significant nutrients for humans and help many functional and regulatory activities in the human body, such as signal transduction, myelination, and synaptic plasticity. Lipids are also involved in the structural developments of the human body . In food, lipid content and fatty acid composition are the two critical congenital parameters to the susceptibility of food to oxidative changes. Lipid content and the fatty acid composition of fat of farm animals varies significantly depending on animal species and the diet. Lipid oxidation causes quality deterioration in food. Depending upon the reaction mechanisms and factors involved, lipid oxidation can be divided into autoxidation, photo-oxidation, and enzyme-catalyzed oxidation. Autoxidation is the most common process of lipid oxidation in foods and is divided into initiation, propagation, and termination stages. 
  • 5.9K
  • 01 Nov 2021
Topic Review
Sexual Robots
The area of human-robot interaction (HRI), particularly concerning sexual robots, has begun to attract interest in various social issues, such as emotions, ethics, philosophy, and psychology. These new relationships between sexual robots and humans have also awakened the interest of the media, the industry, and the maker world since with a 3D printer, it is already possible to create a sexual robot. Society has begun to consider the idea of having sex with robots, and there is the belief that this will be normal in the future. Although there is still no scientific evidence of its therapeutic benefits, many think it can help treat sexual dysfunctions or even help decrease women’s sexual exploitation. Like sex toys, some experts consider sexual robots (or sexbots) to be the future of sex relationships potentially. 
  • 5.9K
  • 11 Jan 2021
Topic Review
Areca nut
Scientific name:  Areca catechu L. Family: Arecaceae Centre of origin: South-East Asia Common name: kamuhu, adakka, adike, Pinang palm, Betel palm, Areca palm, Supari, Kaunga The generic name is derived from the common name used by the people of the Malabar Coast in southwestern India.
  • 5.9K
  • 16 Feb 2022
Topic Review
Fluorescein Derivatives
This entry is dealing with fluorescein and its derivatives and focuses on their uses as pH-sensor in a biological context. It gathers chemical properties of the fluorescein family of compounds combined to biological issues. 
  • 5.9K
  • 17 Dec 2020
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