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Topic Review
Apitherapy
Apitherapy is a complementary and alternative medicine approach, which involves the therapeutic use of various bee products including apilarnil (atomized drone larva) to prevent and treat various diseases.
  • 4.7K
  • 06 Oct 2020
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
Triptycene Synthesis and Derivatization
Since the discovery of triptycenes, great progress has been made regarding their synthetic methodology and the understanding of inter- and intramolecular interactions that involve triptycenes. Several new synthetic approaches have been developed in the last few years, and progress has been made in the context of sterically congested triptycenes and regioselective synthesis of various derivatives.
  • 4.7K
  • 06 Jan 2022
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
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
Challenges to Renewable Energy Transition in China
Climate change and energy issues have become the prominent global challenge and a major concern of China. China’s energy sector, which heavily relies on fossil energy, especially coal, is the largest contributor to China’s carbon emissions. According to the International Energy Agency (IEA), China’s energy consumption accounts for nearly 90% of China’s total CO2 emissions in 2020. The carbon neutrality target poses a huge challenge to China’s energy system, causing energy transition to be the key to the overall decarbonization of China’s economy and society.
  • 4.7K
  • 07 Dec 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
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
Topic Review
Telugu Script
Telugu script (Telugu: తెలుగు లిపి, romanized: Telugu lipi), an abugida from the Brahmic family of scripts, is used to write the Telugu language, a Dravidian language spoken in the India n states of Andhra Pradesh and Telangana as well as several other neighbouring states. The Telugu script is also widely used for writing Sanskrit texts and to some extent the Gondi language. It gained prominence during the Eastern Chalukyas also known as Vengi Chalukya era. It shares extensive similarities with the Kannada script, as it has evolved from Kadamba and Bhattiprolu scripts of the Brahmi family. In 2008, Telugu language was given the status of Classical Languages of India, this status owes to its rich history and heritage.
  • 4.7K
  • 14 Oct 2022
Topic Review
Helichrysum arenarium
Helichrysum arenarium (L.) Moench, belonging to the Asteraceae family, is known in traditional medicine for its diuretic, choleretic, and anti-inflammatory properties. Helichrysum arenarium (sandy everlasting) is a source of active pharmacological compounds used in complementary medicine to prevent digestive and hepatobiliary illnesses. 
  • 4.7K
  • 21 Oct 2022
Topic Review
Principle of Least Action
The principle of least action – or, more accurately, the principle of stationary action – is a variational principle that, when applied to the action of a mechanical system, can be used to obtain the equations of motion for that system. It was historically called "least" because its solution requires finding the path of motion in space that has the least value. The principle can be used to derive Newtonian, Lagrangian and Hamiltonian equations of motion, and even general relativity (see Einstein–Hilbert action). In relativity, a different action must be minimized or maximized. The classical mechanics and electromagnetic expressions are a consequence of quantum mechanics. The stationary action method helped in the development of quantum mechanics. In 1933, the physicist Paul Dirac demonstrated how this principle can be used in quantum calculations by discerning the quantum mechanical underpinning of the principle in the quantum interference of amplitudes. Subsequently Julian Schwinger and Richard Feynman independently applied this principle in quantum electrodynamics. The principle remains central in modern physics and mathematics, being applied in thermodynamics, fluid mechanics, the theory of relativity, quantum mechanics, particle physics, and string theory and is a focus of modern mathematical investigation in Morse theory. Maupertuis' principle and Hamilton's principle exemplify the principle of stationary action. The action principle is preceded by earlier ideas in optics. In Ancient Greece , Euclid wrote in his Catoptrica that, for the path of light reflecting from a mirror, the angle of incidence equals the angle of reflection. Hero of Alexandria later showed that this path was the shortest length and least time. Scholars often credit Pierre Louis Maupertuis for formulating the principle of least action because he wrote about it in 1744 and 1746. However, Leonhard Euler discussed the principle in 1744,[ and evidence shows that Gottfried Leibniz preceded both by 39 years.
  • 4.7K
  • 29 Sep 2022
Topic Review
Trends of Motor Characteristics
It is important to comprehensively evaluate which type of motor is most suitable when designing mechanical systems. This paper presents the results of a survey of the performance of electric and hydraulic servo motors which are commonly used in many mechanical systems and aims to provide quantitative data that can be used as a reference for selecting appropriate motors. We collected data on the characteristics of electric and hydraulic motors and compared and evaluated the characteristics of these servo motors using indexes such as torque, rotating speed, output power, power density, and power rate.
  • 4.7K
  • 20 Jan 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
Hybrid Circuit Breaker
One of the hurdles in the LVDC distribution system is arc flash at the contact points that occurs during the circuit is opening. Unlike alternating current, direct current has no zero points and sustains constantly.  Through 400V class LVDC cutoff test, the operation of the proposed hybrid circuit breaker is verified and the characteristics are analyzed. 
  • 4.7K
  • 24 Jun 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
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
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
Cactaceae
The cactus family is a diverse plant group, native to the Americas. Most of the species included have very variable stem shapes, with singular geometric forms, one of the characteristics why they are considered interesting or even bizarre plants. Cacti vegetative organs have adaptations to arid ecosystems, while possessing showy and beautiful flowers. This set of characteristics has made them very popular among specialists and amateurs. In this entry we address some of the generalities of cacti, focusing on the particular modifications present in their flowers. These peculiarities  make them an interesting model to study the development and evolution of these structures. 
  • 4.7K
  • 21 Jun 2021
Biography
Jürgen Habermas
Jürgen Habermas (born 18 June 1929) is a German philosopher and sociologist in the tradition of critical theory and pragmatism. His work addresses communicative rationality and the public sphere. Associated with the Frankfurt School, Habermas's work focuses on the foundations of epistemology and social theory, the analysis of advanced capitalism and democracy, the rule of law in a critical soc
  • 4.7K
  • 28 Nov 2022
Topic Review
Mindfulness
Mindfulness is the psychological process of purposely bringing one's attention to experiences occurring in the present moment without judgment which one develops through the practice of meditation and through other training. Mindfulness derives from sati, a significant element of Buddhist traditions, and based on Zen, Vipassanā, and Tibetan meditation techniques. Though definitions and techniques of mindfulness are wide-ranging, Buddhist traditions explain what constitutes mindfulness such as how past, present and future moments arise and cease as momentary sense impressions and mental phenomena. Individuals who have contributed to the popularity of mindfulness in the modern Western context include Thích Nhất Hạnh (1926– ), Herbert Benson (1935– ), Jon Kabat-Zinn (1944– ), and Richard J. Davidson (1951– ). Clinical psychology and psychiatry since the 1970s have developed a number of therapeutic applications based on mindfulness for helping people experiencing a variety of psychological conditions. Mindfulness practice has been employed to reduce depression, to reduce stress, anxiety, and in the treatment of drug addiction. Programs based on mindfulness models have been adopted within schools, prisons, hospitals, veterans' centers, and other environments, and mindfulness programs have been applied for additional outcomes such as for healthy aging, weight management, athletic performance, helping children with special needs, and as an intervention during the perinatal period. Clinical studies have documented both physical- and mental-health benefits of mindfulness in different patient categories as well as in healthy adults and children. Research studies have shown a positive relationship between trait mindfulness (see below) and psychological health. The practice of mindfulness appears to provide therapeutic benefits to people with psychiatric disorders, including moderate benefits to those with psychosis. Studies also indicate that rumination and worry contribute to a variety of mental disorders, and that mindfulness-based interventions can reduce both rumination and worry. Further, the practice of mindfulness may be a preventive strategy to halt the development of mental-health problems. There is also evidence that suggest engaging in mindfulness meditation may influence physical health. For example, the psychological habit of repeatedly dwelling on stressful thoughts (i.e., rumination) appears to intensify the physiological effects of the stressor (as a result of the continual activation of the sympathetic nervous system and the hypothalamus-pituitary-adrenal axis) with the potential to lead to physical health related clinical manifestations. Studies indicate that mindfulness meditation, which brings about reductions in rumination, may alter these biological clinical pathways. Further, research indicates that mindfulness may favourably influence the immune system as well as inflammation,Cite error: Closing missing for tag
  • 4.7K
  • 12 Oct 2022
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