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Topic Review
Radar Object Detection
With the improvement of automotive radar resolution, radar target classification has become a hot research topic. Deep radar detection can be classified into point-cloud-based and pre-CFAR-based. Radar point cloud and pre-CFAR data are similar to the LiDAR point cloud and visual image, respectively. Accordingly, the architectures for LiDAR and vision tasks can be adapted for radar detection. 
  • 3.4K
  • 07 Jun 2022
Topic Review
Coracle
A coracle is a small, rounded, lightweight boat of the sort traditionally used in Wales, and also in parts of the West Country and in Ireland, particularly the River Boyne, and in Scotland, particularly the River Spey. The word is also used of similar boats found in India , Vietnam, Iraq and Tibet. The word "coracle" is an English spelling of the original Welsh cwrwgl, cognate with Irish and Scottish Gaelic currach, and is recorded in English text as early as the sixteenth century. Other historical English spellings include corougle, corracle, curricle and coricle.
  • 3.4K
  • 05 Nov 2022
Topic Review
Fluid and Crystallized Intelligence
The concepts of fluid intelligence (gf) and crystallized intelligence (gc) were introduced in 1963 by the psychologist Raymond Cattell. According to Cattell's psychometrically-based theory, general intelligence (g) is subdivided into gf and gc. Fluid intelligence is the ability to solve novel reasoning problems and is correlated with a number of important skills such as comprehension, problem solving, and learning. Crystallized intelligence, on the other hand, involves the ability to deduce secondary relational abstractions by applying previously learned primary relational abstractions.
  • 3.4K
  • 18 Nov 2022
Topic Review
Virtual Reality for Rehabilitation
Virtual reality (VR) is a trending, widely accessible, contemporary technology of increasing utility to biomedical and health applications. VR is the technological experience that allows for a full immersion in virtual spaces with which you can interact via specific wearable or using only your hand. A key feature of all VR applications is interaction. VR ranges from non-immersive to fully immersive, depending on the degree to which the user is isolated from the physical surroundings when interacting with the virtual environment. Non-immersive virtual reality allows for interacting with the environment through mouse or joystick; immersive virtual reality, instead, uses tools that are connected to the human body in order to perform the same motor task. Despite the growing evidence of the positive effects of VR in rehabilitation of functional and cognitive abilities, some systems still raised concerns regarding their acceptability with complex clinical populations, as, for example, the older people. In particular, during trials with immersive systems, few adverse events have been described by participants, including headache and dizziness. Finally, little is known about the perceived effect of the exposure at multisensory input during a complex activity, such as treadmill walking with VR in patients during post-stroke rehabilitation to improve balance and gait ability.
  • 3.4K
  • 30 Jul 2020
Topic Review
Modern Near-Infrared Instrumentation
The ongoing miniaturization of spectrometers creates a perfect synergy with the common advantages of near-infrared (NIR) spectroscopy, which together provide particularly significant benefits in the field of food analysis. The combination of portability and direct onsite application with high throughput and a noninvasive way of analysis is a decisive advantage in the food industry, which features a diverse production and supply chain. A miniaturized NIR analytical framework is readily applicable to combat various problems encountered in modern industry and key sectors of public interest, i.e. food safety risks, agriculture, or environment.
  • 3.4K
  • 30 May 2022
Topic Review
Universal Reconciliation
In Christian theology, universal reconciliation (also called universal salvation, Christian universalism, or in context simply universalism) is the doctrine that all sinful and alienated human souls—because of divine love and mercy—will ultimately be reconciled to God. The doctrine has often been rejected by mainstream Christian religion, which holds to the doctrine of special salvation that only some members of humanity will eventually enter heaven, but it has received support from many prestigious Christian thinkers as well as many groups of Christians. The Bible itself has a variety of verses that, on the surface, seem to support a plurality of views. Universal salvation may be related to the perception of a problem of Hell, standing opposed to ideas such as endless conscious torment in Hell, but may also include a period of finite punishment similar to a state of purgatory. Believers in universal reconciliation may support the view that while there may be a real "Hell" of some kind, it is neither a place of endless suffering nor a place where the spirits of human beings are ultimately 'annihilated' after enduring the just amount of divine retribution. The concept of reconciliation is related to the concept of salvation—i.e., salvation from spiritual and eventually physical death—such that the term "universal salvation" is functionally equivalent. Universalists espouse various theological beliefs concerning the process or state of salvation, but all adhere to the view that salvation history concludes with the reconciliation of the entire human race to God. Many adherents assert that the suffering and crucifixion of Jesus Christ constitute the mechanism that provides redemption for all humanity and atonement for all sins. Unitarian Universalism is a religious movement which emerged in part from the Universalist Church, but it no longer holds any official doctrinal positions, being a non-creedal faith. Universal reconciliation, however, remains a popular viewpoint among many congregations and individual believers including many that have not at all associated with said church. An alternative to universal reconciliation is the doctrine of annihilationism, often in combination with Christian conditionalism. Some Christian leaders, such as influential theologian Martin Luther, have hypothesized other concepts such as 'soul death'.
  • 3.4K
  • 14 Nov 2022
Topic Review
Classical Plant Breeding
Classical plant breeding uses deliberate interbreeding (crossing) of closely or distantly related species to produce new crops with desirable properties. Plants are crossed to introduce traits/genes from a particular variety into a new genetic background. For example, a mildew resistant pea may be crossed with a high-yielding but susceptible pea, the goal of the cross being to introduce mildew resistance without losing the high-yield characteristics. Progeny from the cross would then be crossed with the high-yielding parent to ensure that the progeny were most like the high-yielding parent, (backcrossing), the progeny from that cross would be tested for yield and mildew resistance and high-yielding resistant plants would be further developed. Plants may also be crossed with themselves to produce inbred varieties for breeding. Germplasm resources from genebanks have invaluable for classical breeding. Classical breeding relies heavily on the naturally occuring plant life-cycle and homologous recombination to generate genetic diversity and to eliminate undesirable traits. It may also makes use of a variety of artificial laboratory procedures to overcome obstacles to introduction of useful traits from wild species that do not usually exchange genes with the domesticated line. These approaches include in vitro techniques such as protoplast fusion, embryo rescue or mutagenisis (see below) to generate genetic alterations and produce transgenic plants that would not exist in nature. Traits that breeders' have tried to incorporate into crop plants in the last 100 years include: Intraspecific hybridization within a plant species was demonstrated by Charles Darwin and Gregor Mendel, and was further developed by geneticists and plant breeders. In the early 20th century, plant breeders realized that Mendel's findings on the non-random nature of inheritance could be applied to seedling populations produced through deliberate pollinations to predict the frequencies of different types. In 1908, George Harrison Shull described heterosis, also known as hybrid vigor. Heterosis describes the tendency of the progeny of a specific cross to outperform both parents. The detection of the usefulness of heterosis for plant breeding has lead to the development of inbred lines that reveal a heterotic yield advantage when they are crossed. Maize was the first species where heterosis was widely used to produce hybrids. Heterosis made breeders aware of the broad practical value of many genes carried in plant chromosomes even when the identity and trait specified by the paticular genes is unknown - that is that diverse plant Germplasm is generally valuable to the breeder. By the 1920s, statistical methods were developed to analyze gene action and distinguish heritable variation from variation caused by environment. In 1933, another important breeding technique, cytoplasmic male sterility (CMS), developed in maize, was described by Marcus Morton Rhoades. CMS is a maternally inherited trait that makes the plant produce sterile pollen, enabling the production of hybrids and removing the need for detasseling maize plants. The scientific use of Transgenic plants in farming gained impetus in the 1930s when a transgenic wheat variety named Hope bred by E. S. McFadden with a transgene originating in a wild grass saved American wheat growers from devastating stem rust outbreaks. These early breeding techniques resulted in large yield increase in the United States in the early 20th century. Similar yield increases were not produced elsewhere until after World War II, the Green Revolution increased crop production in the developing world in the 1960s. Success stories like Hope and hybrid-vigor made it clear that genetic divesity present in wild-species was of great potential value to plant breeders, and eventially lead to the establisment of Germplasm collections consisting of seed-banks devoted to preservation of potentially useful uncharacterised traits for posterity. Following World War II a number of techniques were developed that allowed plant breeders to hybridize distantly related species, and artificially induce genetic diversity. When distantly related species are crossed, plant breeders make use of a number of plant tissue culture techniques to produce progeny from other wise fruitless mating. Interspecific and intergeneric hybrids are produced from a cross of related species or genera that do not normally sexually reproduce with each other. These crosses are referred to as Wide crosses. The cereal triticale is a wheat and rye hybrid. The first generation created from the cross was sterile, so the cell division inhibitor colchicine was used to double the number of chromosomes in the cell. Cells with an uneven number of chromosomes are sterile. Failure to produce a hybrid may be due to pre- or post-fertilization incompatibility. If fertilization is possible between two species or genera, the hybrid embryo may abort before maturation. If this does occur the embryo resulting from an interspecific or intergeneric cross can sometimes be rescued and cultured to produce a whole plant. Such a method is referred to as Embryo Rescue. This technique has been used to produce new rice for Africa, an interspecific cross of Asian rice (Oryza sativa) and African rice (Oryza glaberrima). Hybrids may also be produced by a technique called protoplast fusion. In this case protoplasts are fused, usually in an electric field. Viable recombinants can be regenerated in culture. Chemical mutagens like EMS and DMSO, radiation and transposons are used to generate mutants with desirable traits to be bred with other cultivars. Classical plant breeders also generate genetic diversity within a species by exploiting a process called somaclonal variation, which occurs in plants produced from tissue culture, particularly plants derived from callus. Induced polyploidy, and the addition or removal of chromosomes using a technique called chromosome engineering also found uses. When a desirable trait has been bred into a species, a number of crosses to the favoured parent are made to make the new plant as similar as the parent as possible. Returning to the example of the mildew resistant pea being crossed with a high-yielding but susceptible pea, to make the mildew resistant progeny of the cross most like the high-yielding parent, the progeny will be crossed back to that parent for several generations (See backcrossing ). This process removes most of the genetic contribution of the mildew resistant parent. Classical breeding is therefore a cyclical process. It should be noted that with classical breeding techniques, the breeder does not know exactly what genes have been introduced to the new cultivars. Some scientists therefore argue that plants produced by classical breeding methods should undergo the same safety testing regime as genetically modified plants. There have been instances where plants bred using classical techniques have been unsuitable for human consumption, for example the poison solanine was accidentally re-introduced into varieties of potato through plant breeding.
  • 3.4K
  • 14 Oct 2022
Topic Review
Ionic Liquids in Electrochemistry
The roles of room temperature ionic liquids (RTILs) and RTIL based solvent systems as proposed alternatives for conventional organic electrolyte solutions are described. Ionic liquids are introduced as well as the relevant properties for their use in electrochemistry (reduction of ohmic losses), such as diffusive molecular motion and ionic conductivity.
  • 3.4K
  • 21 Jan 2021
Topic Review
Working Fluids
Heat engines, refrigeration cycles and heat pumps usually involve a fluid to and from which heat is transferred while undergoing a thermodynamic cycle. This fluid is called the working fluid. Refrigeration and heat pump technologies often refer to working fluids as refrigerants. Most thermodynamic cycles make use of the latent heat (adventages of phase change) of the working fluid. In case of other cycles the working fluid remains in gaseous phase while undergoing all the processes of the cycle. When it comes to heat engines, working fluid generally undergoes a combustion process as well, for example in internal combustion engines or gas turbines. There are also technologies in heat pump and refrigeration, where working fluid does not change phase, such as reverse Brayton or Stirling cycle. This article summarises the main critera of selecting working fluids for a thermodynamic cycle, such as heat engines including low grade heat recovery using Organic Rankine Cycle (ORC) for geothermal energy, waste heat, thermal solar energy or biomass and heat pumps and refrigeration cycles. The article addresses how working fluids affect technological applications, where the working fluid undergoes a phase transition and does not remain in its original (mainly gaseous) phase during all the processes of the thermodynamic cycle. Finding the optimal working fluid for a given purpose – which is essential to achieve higher energy efficiency in the energy conversion systems – has great impact on the technology, namely it does not just influence operational variables of the cycle but also alters the layout and modifies the design of the equipment. Selection criteria of working fluids generally include thermodynamic and physical properties besides economical and environmental factors, but most often all of these criteria are used together.
  • 3.4K
  • 04 Nov 2022
Topic Review
Fruit Development in Sweet Cherry
Fruits are an important source of vitamins, minerals and nutrients in the human diet. They also contain several compounds of nutraceutical importance that have significant antioxidant and anti-inflammatory roles. Cherries contain high concentrations of bioactive compounds and minerals, including calcium, phosphorous, potassium and magnesium, and it is, therefore, unsurprising that cherry consumption has a positive impact on health. The sweet cherry fruit is a drupe—an indehiscent fruit of 1–2 cm in diameter (in some cultivars the diameter can be larger) that has an attractive appearance due to its color (bright red to dark purple depending on the cultivar) and desirable, intense flavor.
  • 3.4K
  • 16 Jun 2022
Topic Review
Diagnosis of Plant Virus Diseases
Among the plant pathogens, viruses (and viroids), which are transmitted by a living organism called a vector, are the major infectious agents that cause plant disease. Once a plant virus infects a susceptible host, it can spread to another plant by means of vector-mediated transmission (horizontally) or from parents to offspring (vertically). Since accurate diagnosis methods are of pivotal importance for viral diseases control, the current and emerging technologies for the detection of these plant pathogens are described.
  • 3.4K
  • 27 Jan 2022
Topic Review
Neurobiological Links between Stress and Traumatic Brain Injury
Neurological dysfunctions commonly occurs after mild or moderate traumatic brain injury (TBI). Although most TBI patients recover from such dysfunction in a short period of time, some present with persistent neurological deficits. Stress is a potential factor that is involved in recovery from neurological dysfunction after TBI. However, there has been limited research on the effects and mechanisms of stress on neurological dysfunctions due to TBI. The effects of TBI and stress on neurological dysfunctions and different brain regions such as the prefrontal cortex, hippocampus, amygdala, and hypothalamus are investigated, and the neurobiological links and mechanisms between stress and TBI are explored.
  • 3.4K
  • 07 Sep 2022
Topic Review
AgNPs
Elementary silver nanoparticles (AgNPs) are of great interest because of their various probable medical application. Due to their antimicrobial activity, low toxicity and inexpensive cost, the mechanism of silver nanoparticles biosynthesis in bacterial, fungal and plant cells is extremely exciting from the point of view of the different cellular compounds participation in it: proteins, enzymes, acids, etc.
  • 3.4K
  • 15 Dec 2020
Topic Review
Long-Term Care Insurance Pilot in China
China launched long-term care insurance (LTCI) pilot program in 2016, there are great challenges associated with developing a sustainable LTCI system due to limited financial resources and a rapid increase in the aging population. It is needed to evaluate the impact of LTCI policy development from diverse perspectives and using various evaluation methods.
  • 3.4K
  • 20 Jun 2022
Topic Review
Cultural Divide
A cultural divide is "a boundary in society that separates communities whose social economic structures, opportunities for success, conventions, styles, are so different that they have substantially different psychologies". A cultural divide is the virtual barrier caused by cultural differences, that hinder interactions, and harmonious exchange between people of different cultures. For example, avoiding eye contact with a superior shows deference and respect in East Asian cultures, but can be interpreted as suspicious behavior in Western cultures. Studies on cultural divide usually focus on identifying and bridging the cultural divide at different levels of society.
  • 3.4K
  • 13 Oct 2022
Topic Review
Stock-Flow Consistent Model
Stock-Flow Consistent (SFC) models are a family of macroeconomic models based on a rigorous accounting framework, which guarantees a correct and comprehensive integration of all the flows and the stocks of an economy. These models were first developed in the mid-20th century but have recently become popular, particularly within the post-Keynesian school of thought.
  • 3.4K
  • 19 Oct 2022
Topic Review
Properties and Applications of Levan
Polysaccharides play a crucial role in medicine, pharmacy, and cosmetology, as well as in the production of biofuels and biomaterials. Among microbial biopolymers, microbial levan, a fructose polysaccharide, holds significant promise due to its high productivity and chemical diversity. Levan exhibits a wide range of properties, including film-forming ability, biodegradability, non-toxicity, self-aggregation, encapsulation, controlled release capacity, water retention, immunomodulatory and prebiotic activity, antimicrobial and anticancer activity, as well as high biocompatibility. These exceptional properties position levan as an attractive candidate for nature-based materials in food production, modern cosmetology, medicine, and pharmacy. 
  • 3.4K
  • 26 Jul 2023
Topic Review
Mandibular Leeway Space of Taiwanese Children
Leeway space, the most crucial space for the alignment of permanent teeth, is the difference between the sum of the mesiodistal crown widths of the primary canines and molars and that of their successors, the permanent canines and premolars. Primary molars have greater mesiodistal crown widths than the permanent premolars that replace them, especially the primary second molar. Leeway space has been preserved and utilized to resolve crowding, particularly by allowing the first molars to drift mesially to establish a Class I molar relationship in the late mixed dentition.
  • 3.4K
  • 10 Nov 2021
Topic Review
Virtual Currency
Virtual currency, or virtual money, is a type of unregulated, digital money, which is issued and usually controlled by its developers and used and accepted among the members of a specific virtual community. The U.S. Commodity Futures Trading Commission has warned investors against pump and dump schemes that use virtual currencies. The Financial Crimes Enforcement Network (FinCEN), a bureau of the US Treasury, defined virtual currency in its guidance published in 2013. In 2014, the European Banking Authority defined virtual currency as "a digital representation of value that is neither issued by a central bank or a public authority, nor necessarily attached to a fiat currency, but is accepted by natural or legal persons as a means of payment and can be transferred, stored or traded electronically". By contrast, a digital currency that is issued by a central bank is defined as "central bank digital currency".
  • 3.4K
  • 20 Oct 2022
Topic Review
Cairn
A cairn is a man-made pile (or stack) of stones. The word cairn comes from the Scottish Gaelic: càrn [ˈkʰaːrˠn̪ˠ] (plural càirn [ˈkʰaːrˠɲ]). Cairns have been and are used for a broad variety of purposes, from prehistoric times to the present. In modern times, cairns are often erected as landmarks, a use they have had since ancient times. However, since prehistory, they have also been built and used as burial monuments; for defense and hunting; for ceremonial purposes, sometimes relating to astronomy; to locate buried items, such as caches of food or objects; and to mark trails, among other purposes. Cairns are used as trail markers in many parts of the world, in uplands, on moorland, on mountaintops, near waterways and on sea cliffs, as well as in barren deserts and tundras. They vary in size from small stone markers to entire artificial hills, and in complexity from loose conical rock piles to delicately balanced sculptures and elaborate feats of megalithic engineering. Cairns may be painted or otherwise decorated, whether for increased visibility or for religious reasons. An ancient example is the inuksuk (plural inuksuit), used by the Inuit, Inupiat, Kalaallit, Yupik, and other peoples of the Arctic region of North America. Inuksuit are found from Alaska to Greenland. This region, above the Arctic Circle, is dominated by the tundra biome and has areas with few natural landmarks.
  • 3.4K
  • 30 Nov 2022
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