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Topic Review
Contraindications to Initiation of ECMO
Extracorporeal membrane oxygenation (ECMO) is increasingly used for acute respiratory failure with few absolute but many relative contraindications. The contraindications to the initiation of ECMO therapy are not uniformly agreed upon, and each center, as well as each provider involved in the indication for the initiation of ECMO, weights them differently. Whereas absolute contraindications immediately discourage ECMO therapy, relative contraindications should trigger a very thorough consideration of this option. Although relative contraindications should not per se exclude patients from a life-saving procedure such as ECMO, their concurrence may lead to the decision to forgo this procedure. When relative contraindications add up, they might accumulate to a point where they (should) be considered absolute contraindications.
  • 4.7K
  • 16 Sep 2021
Topic Review
Local Brazilian Goat Breeds
Local Brazilian goat breeds comprise six main groups (Moxotó, Canindé, Repartida, Marota, Graúna, and Azul) and the non descript group derived from crosses.  Local Brazilian goat breeds is a vital genetic resource because they represent the main source of animal's protein to local smallholder communities in the Brazilian semiarid. 
  • 4.7K
  • 20 Oct 2020
Topic Review
Mnemonic
A mnemonic (/nəˈmɒnɪk/) device, or memory device, is any learning technique that aids information retention or retrieval (remembering) in the human memory for better understanding. Mnemonics make use of elaborative encoding, retrieval cues, and imagery as specific tools to encode information in a way that allows for efficient storage and retrieval. Mnemonics aid original information in becoming associated with something more accessible or meaningful—which, in turn, provides better retention of the information. Commonly encountered mnemonics are often used for lists and in auditory form, such as short poems, acronyms, initialisms, or memorable phrases, but mnemonics can also be used for other types of information and in visual or kinesthetic forms. Their use is based on the observation that the human mind more easily remembers spatial, personal, surprising, physical, sexual, humorous, or otherwise "relatable" information, rather than more abstract or impersonal forms of information. The word "mnemonic" is derived from the Ancient Greek word μνημονικός (mnēmonikos), meaning 'of memory' or 'relating to memory' and is related to Mnemosyne ("remembrance"), the name of the goddess of memory in Greek mythology. Both of these words are derived from μνήμη (mnēmē), 'remembrance, memory'. Mnemonics in antiquity were most often considered in the context of what is today known as the art of memory. Ancient Greeks and Romans distinguished between two types of memory: the "natural" memory and the "artificial" memory. The former is inborn, and is the one that everyone uses instinctively. The latter in contrast has to be trained and developed through the learning and practice of a variety of mnemonic techniques. Mnemonic systems are techniques or strategies consciously used to improve memory. They help use information already stored in long-term memory to make memorization an easier task.
  • 4.7K
  • 21 Oct 2022
Topic Review
Maize Breeding
Maize or corn (Zea mays L.), a plant species particularly generous in its production potential and in its wide diversity of uses, is fundamental for the development of a modern and efficient agriculture. Globally, maize ranks third in area and first in production, ahead of wheat and rice. Due to the large areas corn occupies, but especially to its yielding performance, maize is a major source of food for the world’s population. In addition to its nutritional importance for humans, corn is also basic food for animal feed and valuable raw material for industrial processing. The importance of corn for human health results from the fact that it is a food rich in nutrients, especially energy of 355 kcal per 100 g flour with 15% moisture, compared to 352 kcal for wheat flour, 348 kcal for rye flour, and 346 kcal for hulled barley. As food, maize also has some shortcomings, of which that the low amount of some essential amino acids was noted, such as lysine and tryptophan. Maize is also a valuable raw material for industry, extracting oil, starch, alcohol, glucose, and other products such as syrup, pectin, dextrin, plastics, lactic acid, acetic acid, acetone, dyes, and synthetic rubber from its grains. Paper, cardboard, and nitrocellulose can be made from corn stalks. Every part of the maize plant has economic worth, including the grain, leaves, stalk, tassel, and cob, which can be used to make a variety of food and non-food goods. Maize breeding research has traditionally concentrated on enhancing productive potential in newly created maize varieties because this criterion ensures a crop’s economic efficiency. Nowadays, genomics tools are essential for a precise, fast, and efficient breeding of crops especially in the context of climate challenges, but also may in the future represent a way to accelerate the processes of de novo domestication of the species.
  • 4.7K
  • 24 Oct 2022
Topic Review
Stress
Stress, either physiological, biological or psychological, is an organism's response to a stressor such as an environmental condition. Stress is the body's method of reacting to a condition such as a threat, challenge or physical and psychological barrier. There are two hormones that an individual produces during a stressful situation, these are well known as adrenaline and cortisol. Stimuli that alter an organism's environment are responded to by multiple systems in the body. In humans and most mammals, the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis are the two major systems that respond to stress. The sympathoadrenal medullary (SAM) axis may activate the fight-or-flight response through the sympathetic nervous system, which dedicates energy to more relevant bodily systems to acute adaptation to stress, while the parasympathetic nervous system returadrenaliney to homeostasis. The second major physiological stress-response center, the HPA axis, regulates the release of cortisol, which influences many bodily functions such as metabolic, psychological and immunological functions. The SAM and HPA axes are regulated by several brain regions, including the limbic system, prefrontal cortex, amygdala, hypothalamus, and stria terminalis. Through these mechanisms, stress can alter memory functions, reward, immune function, metabolism and susceptibility to diseases. Disease risk is particularly pertinent to mental illnesses, whereby chronic or severe stress remains a common risk factor for several mental illnesses. One system suggests there are five types of stress labeled "acute time-limited stressors", "brief naturalistic stressors", "stressful event sequences", "chronic stressors", and "distant stressors". An acute time-limited stressor involves a short-term challenge, while a brief natural stressor involves an event that is normal but nevertheless challenging. A stressful event sequence is a stressor that occurs, and then continues to yield stress into the immediate future. A chronic stressor involves exposure to a long-term stressor, and a distant stressor is a stressor that is not immediate.
  • 4.7K
  • 28 Oct 2022
Topic Review
Competition
Competition is an interaction between organisms or species in which both require a resource that is in limited supply (such as food, water, or territory). Competition lowers the fitness of both organisms involved, since the presence of one of the organisms always reduces the amount of the resource available to the other. In the study of community ecology, competition within and between members of a species is an important biological interaction. Competition is one of many interacting biotic and abiotic factors that affect community structure, species diversity, and population dynamics (shifts in a population over time). There are three major mechanisms of competition: interference, exploitation, and apparent competition (in order from most direct to least direct). Interference and exploitation competition can be classed as "real" forms of competition, while apparent competition is not, as organisms do not share a resource, but instead share a predator. Competition among members of the same species is known as intraspecific competition, while competition between individuals of different species is known as interspecific competition. According to the competitive exclusion principle, species less suited to compete for resources must either adapt or die out, although competitive exclusion is rarely found in natural ecosystems. According to evolutionary theory, competition within and between species for resources is important in natural selection. More recently, however, researchers have suggested that evolutionary biodiversity for vertebrates has been driven not by competition between organisms, but by these animals adapting to colonize empty livable space; this is termed the 'Room to Roam' hypothesis.
  • 4.7K
  • 28 Nov 2022
Topic Review
Pharmaceutical Hydrates Analysis
This entry discusses a set of instrumental and computational methods that are used to characterize hydrated forms of APIs (active pharmaceutical ingredients). The focus has been put on highlighting advantages as well as on presenting some limitations of the selected analytical approaches. This has been performed in order to facilitate the choice of an appropriate method depending on the type of the structural feature that is to be analyzed, that is, degree of hydration, crystal structure and dynamics, and (de)hydration kinetics. The presented techniques include X-ray diffraction (single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD)), spectroscopic (solid state nuclear magnetic resonance spectroscopy (ssNMR), Fourier-transformed infrared spectroscopy (FT-IR), Raman spectroscopy), thermal (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)), gravimetric (dynamic vapour sorption (DVS)), and computational (molecular mechanics (MM), Quantum Mechanics (QM), molecular dynamics (MD)) methods. Further, the successful applications of the presented methods in the studies of hydrated APIs as well as studies on the excipients’ influence on these processes have been described in many examples.
  • 4.7K
  • 19 Oct 2020
Topic Review
Chrysanthemum Morifolium
Chrysanthemum morifolium (also known as florist's daisy and hardy garden mum) is a species of perennial plant from family Asteraceae.
  • 4.7K
  • 02 Nov 2022
Topic Review
Historicism (Christianity)
In Christian eschatology, historicism is a method of interpretation of biblical prophecies which associates symbols with historical persons, nations or events. The main primary texts of interest to Christian historicists include apocalyptic literature, such as the Book of Daniel and the Book of Revelation. It sees the prophecies of Daniel as being fulfilled throughout history, extending from the past through the present to the future. It is sometimes called the continuous historical view. Commentators have also applied historicist methods to ancient Jewish history, to the Roman Empire, to Islam, to the Papacy, to the Modern era, and to the end time. The historicist method starts with Daniel 2 and works progressively through consecutive prophecies of the book–chapters 7, 8 and 11–resulting in a view of Daniel's prophecies very different from preterism and futurism. Almost all Protestant Reformers from the Reformation into the 19th century held historicist views.
  • 4.7K
  • 18 Oct 2022
Topic Review
Plant Promoters
One of the strategies to overcome diseases or abiotic stress in crops is the use of improved varieties. Genetic improvement could be accomplished through different methods, including conventional breeding, induced mutation, genetic transformation, or gene editing. The gene function and regulated expression through promoters are necessary for transgenic crops to improve specific traits. The variety of promoter sequences has increased in the generation of genetically modified crops because they could lead to the expression of the gene responsible for the improved trait in a specific manner.
  • 4.7K
  • 03 Jul 2023
Topic Review
Application of Hydrogen Storage Tanks
The most practical way of storing hydrogen gas for fuel cell vehicles is to use a composite overwrapped pressure vessel. Depending on the driving distance range and power requirement of the vehicles, there can be various operational pressure and volume capacity of the tanks, ranging from passenger vehicles to heavy-duty trucks. The current commercial hydrogen storage method for vehicles involves storing compressed hydrogen gas in high-pressure tanks at pressures of 700 bar for passenger vehicles and 350 bar to 700 bar for heavy-duty trucks. In particular, hydrogen is stored in rapidly refillable onboard tanks, meeting the driving range needs of heavy-duty applications, such as regional and line-haul trucking.
  • 4.7K
  • 28 Jul 2023
Topic Review
Maze Solving Algorithm
There are a number of different maze solving algorithms, that is, automated methods for the solving of mazes. The random mouse, wall follower, Pledge, and Trémaux's algorithms are designed to be used inside the maze by a traveler with no prior knowledge of the maze, whereas the dead-end filling and shortest path algorithms are designed to be used by a person or computer program that can see the whole maze at once. Mazes containing no loops are known as "simply connected", or "perfect" mazes, and are equivalent to a tree in graph theory. Thus many maze solving algorithms are closely related to graph theory. Intuitively, if one pulled and stretched out the paths in the maze in the proper way, the result could be made to resemble a tree.
  • 4.7K
  • 08 Nov 2022
Topic Review
Origin and Terrestrialization of Arthropods
Arthropods, the most diverse form of macroscopic life in the history of the Earth, originated in the sea. Since the early Cambrian, at least ~518 million years ago, these animals have dominated the oceans of the world. By the Silurian–Devonian, the fossil record attests to arthropods becoming the first animals to colonize land, However, a growing body of molecular dating and palaeontological evidence suggests that the three major terrestrial arthropod groups (myriapods, hexapods, and arachnids), as well as vascular plants, may have invaded land as early as the Cambrian–Ordovician. These dates precede the oldest fossil evidence of those groups and suggest an unrecorded continental “Cambrian explosion” a hundred million years prior to the formation of early complex terrestrial ecosystems in the Silurian–Devonian.
  • 4.7K
  • 04 Nov 2022
Topic Review
Layer-Scale Transfer Techniques
Layer transfer is a technique to transfer a layer of a particular semiconductor material, often of a wafer-scale size, from the original substrate to the target substrate of interest.
  • 4.7K
  • 26 Apr 2021
Topic Review
Functional Pyrazolo[1,5-a]pyrimidines
Pyrazolo[1,5-a]pyrimidine (PP) derivatives are an enormous family of N-heterocyclic compounds that possess a high impact in medicinal chemistry and have attracted a great deal of attention in material science recently due to their significant photophysical properties.
  • 4.7K
  • 14 Jul 2021
Topic Review
Muscle Tone Physiology
The simple definition of tone as the resistance to passive stretch is physiologically a complex interlaced network encompassing neural circuits in the brain, spinal cord, and muscle spindle. Disorders of muscle tone can arise from dysfunction in these pathways and manifest as hypertonia or hypotonia. The loss of supraspinal control mechanisms gives rise to hypertonia, resulting in spasticity or rigidity. On the other hand, dystonia and paratonia also manifest as abnormalities of muscle tone, but arise more due to the network dysfunction between the basal ganglia and the thalamo-cerebello-cortical connections. 
  • 4.7K
  • 19 May 2021
Topic Review
Growth Factors Regulation in Angiogenesis
Cardiovascular disease (CVD) remains a major cause of morbidity and mortality all over the world. Angiogenesis is controlled by cell–cell and cell-extracellular matrix (ECM) interactions through crosstalk between vascular endothelial growth factor (VEGF) and Notch signaling mechanisms. 
  • 4.7K
  • 31 May 2023
Topic Review
Financial Accounting and Sustainability Accounting
A phenomenon in development of accounting knowledge is the generalisation of accounting  principles and concepts from the traditional (financial) domain/context to the sustainability domain/context. This phenomenon draws debates between two schools. Some scholars support the way of simulation, maintaining it is necessary and inevitable for sustainability accounting researchers and practitioners to draw knowledge the financial accounting that has been familiar for them. But some scholars take a critical stance against the simulation, arguing that it is too difficult to apply financial accounting concepts to sustainability practices, for the two accounting contexts are significantly different from each other. But the sustainability accounting application of the materiality concept indicates another side of the phenomenon. That is, sustainability accounting academy should neither give up or discourage the way of generalisation, nor simply and directly simulate the definitions and practices of financial accounting concepts. 
  • 4.7K
  • 29 Oct 2020
Topic Review
Start School Later Movement
The movement to start school later consists of efforts by health care professionals, sleep scientists, educators, economists, legislators, parents, students, and other concerned citizens to restore a later start to the school day. Based on a growing body of evidence that starting middle and high schools too early in the morning is unhealthy, counterproductive, and incompatible with adolescent sleep needs and patterns. During the second half of the 20th century, many public schools in the United States began shifting instructional time earlier than the more conventional bell time, thought to be about 9 a.m. Today it is common for American schools to begin the instructional day in the 7 a.m. hour and end about seven hours later, around 2 p.m. Most sleep research suggests that morning classes should begin no earlier than 8:30 a.m. for middle and high school students. Advocates of a return to later school start times argue that sleep and school hours should be viewed as a public health issue, citing evidence linking early school start times to widespread sleep deprivation among teenagers as well as a wide array of acute and chronic physical, psychological, and educational problems. Not only do students consistently get significantly more sleep on school nights when their schools move to later start times, but later school hours have been consistently linked with improved school performance, reduced impulsiveness, and greater motivation, as well as with lower rates of depression, tardiness, truancy, and morning automobile accidents. Recent (2011) studies suggest that early school start times disproportionately hurt economically disadvantaged students and may even negatively impact future earning potential of students, offsetting any financial savings to the school system attributed to earlier hours.
  • 4.7K
  • 06 Oct 2022
Topic Review
Hotels' Services and Amenities for Family Tourism
Travelling families are interested in urban tourism due to its cognitive and entertainment aspects. Some expectations of parents travelling with children are the same independent of the accommodation location. It can be stated that the most important factor regarding family tourism, which should make the services and amenities offered by hotels diverse, is the age of children. It is their age that determines childrens’ needs and interests from the earliest period of infancy to early school age. The biggest challenge for the hoteliers is to prepare an offer that meets the expectations of families with children of different ages (the greater the age difference is, the more difficult it becomes to meet parents’ requirements regarding amenities and hotel facilities).
  • 4.7K
  • 04 Aug 2022
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