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Topic Review

Sub Synchronous Oscillation Phenomenon

The definition of sub synchronous oscillation (SSO) according to the IEEE Sub Synchronous Resonance Working Group is as follows. “Sub synchronous oscillation is an electric power system condition where the electric network exchanges significant energy with a turbine generator at one or more of the natural frequencies of the combined system below the synchronous frequency of the system following a disturbance from equilibrium”. According to the classification of SSO by the IEEE Sub Synchronous Resonance Working Group, there are two types of SSO, namely sub synchronous resonance (SSR) and device dependent sub synchronous oscillation (DDSSO). Sub synchronous control interaction (SSCI) and sub synchronous torsional interaction (SSTI) are other types of SSO. However, they are not included in the formal classification.

8.7K
09 Dec 2022

Topic Review

Devil in Christianity

The Devil in Christianity is the personification of evil and author of sin, who rebelled against God in an attempt to become equal to God himself.[lower-alpha 1] He is depicted as a fallen angel, who was expelled from Heaven at the beginning of time, before God created the material world, and is in constant opposition to God. The devil is identified with several figures in the Bible including the serpent in the Garden of Eden, Lucifer, Satan, the tempter of the Gospels, Leviathan, and the dragon in the Book of Revelation. Early scholars discussed the role of the devil. Scholars influenced by neoplatonic cosmology, like Origen and Pseudo-Dionysius, portrayed the devil as representing deficiency and emptiness, the entity most remote from the divine. According to Augustine of Hippo the realm of the devil is not nothingness, but an inferior realm standing in opposition to God. The standard Medieval depiction of the devil was set up by Gregory the Great. He integrated the devil, as the first creation of God, into the Christian angelic hierarchy as the highest of the angels (either a cherub or a seraph). But as high as he stood in heaven, so far he fell into the depths of hell and became the leader of demons. Since the early reformation period, the devil was imagined as an increasingly powerful entity, with not only a lack of goodness but also a conscious will against God, his word, and his creation. Simultaneously, some reformists interpreted the devil as a mere metaphor for human's inclination to sin and so downgraded the importance of the devil. While the devil played for most scholars no significant role in the Modern Era, he became more important in contemporary Christianity again. At various times in history, some people such as the Cathars and the Bogomiles, as well as theologians like Marcion and Valentinus, believed that the devil was involved in creating the world. Today these views are not part of mainstream Christianity.

8.7K
06 Dec 2022

Topic Review

List of Asteroids in Astrology

Asteroids are relatively new to astrology, having only been discovered in the 19th century. However, some of them (especially the largest of them), are believed by some astrologers to influence human affairs. Still though, they are often ignored within mainstream systems of astrology, especially in more traditional astrology systems like Vedic astrology or Hellenistic astrology. Their use has become significant to a few Western astrologers yet still only a minority of astrologers use the asteroids in chart interpretation.

8.6K
22 Nov 2022

Topic Review

History of Zoology (Through 1859)

The history of zoology before Charles Darwin's 1859 theory of evolution traces the organized study of the animal kingdom from ancient to modern times. Although the concept of zoology as a single coherent field arose much later, systematic study of zoology is seen in the works of Aristotle and Galen in the ancient Greco-Roman world. This work was developed in the Middle Ages by Islamic medicine and scholarship, and in turn their work was extended by European scholars such as Albertus Magnus. During the European Renaissance and early modern period, zoological thought was revolutionized in Europe by a renewed interest in empiricism and the discovery of many novel organisms. Prominent in this movement were the anatomist Vesalius and the physiologist William Harvey, who used experimentation and careful observation, and naturalists such as Carl Linnaeus and Buffon who began to classify the diversity of life and the fossil record, as well as the development and behavior of organisms. Microscopy revealed the previously unknown world of microorganisms, laying the groundwork for cell theory. The growing importance of natural theology, partly a response to the rise of mechanical philosophy, encouraged the growth of natural history (although it entrenched the argument from design). Over the 18th and 19th centuries, zoology became increasingly professional scientific disciplines. Explorer-naturalists such as Alexander von Humboldt investigated the interaction between organisms and their environment, and the ways this relationship depends on geography—laying the foundations for biogeography, ecology and ethology. Naturalists began to reject essentialism and consider the importance of extinction and the mutability of species. Cell theory provided a new perspective on the fundamental basis of life. These developments, as well as the results from embryology and paleontology, were synthesized in Charles Darwin's theory of evolution by natural selection. In 1859, Darwin placed the theory of organic evolution on a new footing, by his discovery of a process by which organic evolution can occur, and provided observational evidence that it had done so.

8.6K
21 Apr 2023

Topic Review

Bell Peppers (Capsicum annum L.)

The bell pepper is highly consumed worldwide due to its exotic colors (green, red, yellow, orange, and purple), flavor, and nutritional value. However, after processing bell pepper products, waste remains (seeds, peel, stem, and leaves), representing desirable raw material to obtain phytochemical compounds. They contain diverse bioactive compounds with interesting biological activities (in vivo and in vitro) and applications.

8.6K
22 Oct 2021

Topic Review

Outrigger Canoe

The outrigger canoe is a type of canoe featuring one or more lateral support floats known as outriggers, which are fastened to one or both sides of the main hull. Smaller canoes often employ a single outrigger on the port side, while larger canoes may employ a single-outrigger, double-outrigger, or double-hull configuration (see also catamaran). The sailing canoes are an important part of the Austronesian heritage. They are also very popular in Puerto Rico. Unlike a single-hulled canoe, an outrigger or double-hull canoe generates stability as a result of the distance between its hulls rather than due to the shape of each individual hull. As such, the hulls of outrigger or double-hull canoes are typically longer, narrower and more hydrodynamically efficient than those of single-hull canoes. Compared to other types of canoes, outrigger canoes can be quite fast, yet are also capable of being paddled and sailed in rougher water. This paddling technique, however, differs greatly from kayaking or rowing. The paddle, or blade, used by the paddler is single sided, with either a straight or a double-bend shaft.

8.6K
19 Oct 2022

Topic Review

Trillian is a proprietary multiprotocol instant messaging application created by Cerulean Studios. It is currently available for Microsoft Windows, Mac OS X, Linux, Android, iOS, BlackBerry OS, and the Web. It can connect to multiple IM services, such as AIM, Bonjour, Facebook Messenger, Google Talk (Hangouts), IRC, XMPP (Jabber), VZ, and Yahoo! Messenger networks; as well as social networking sites, such as Facebook, Foursquare, LinkedIn, and Twitter; and email services, such as POP3 and IMAP. Trillian no longer supports Windows Live Messenger or Skype as these services have combined and Microsoft chose to discontinue Skypekit. They also no longer support connecting to MySpace, and no longer support a distinct connection for Gmail, Hotmail or Yahoo! Mail although these can still be connected to via POP3 or IMAP. Currently, Trillian supports Facebook, Google, Jabber (XMPP), and Olark. Initially released July 1, 2000, as a freeware IRC client, the first commercial version (Trillian Pro 1.0) was published on September 10, 2002. The program was named after Trillian, a fictional character in The Hitchhiker's Guide to the Galaxy by Douglas Adams. A previous version of the official web site even had a tribute to Douglas Adams on its front page. On August 14, 2009, Trillian "Astra" (4.0) for Windows was released, along with its own Astra network. Trillian 5 for Windows was released in May 2011, and Trillian 6.0 was initially released in February 2017.

8.6K
21 Oct 2022

Topic Review

Islam in Albania (1913–1944)

Islam in Albania (1913–1944) was characterised by an increasing secularisation of Albanian society which had begun with Albanian Independence in 1912 carrying on influences from the Albanian National Awakening. During the interwar period, new local Muslim institutions such as the Muslim Community of Albania arose that severed ties with the Ottoman Caliphate and placed a focus on localising Islam in Albania. The Albanian state also played a significant role in that process through state interference and pressuring the uptake of reforms by those institutions and wider Muslim society. Measures that were adopted were banning the veil and others which were interpreted as modernising Albania. These events caused tensions within parts of Muslim society between conservatives and those who viewed themselves as progressives which caused discussions and reflections about the future role of Islam in Albania and Albanian identity. The interwar era also saw Sufi Islam expand in Albania with various orders gaining new adherents with the largest, the Bektashi Order moving its world headquarters to Albania.

8.6K
15 Nov 2022

Topic Review

A hardiness zone is a geographic area defined to encompass a certain range of climatic conditions relevant to plant growth and survival. The original and most widely-used system, developed by the United States Department of Agriculture (USDA) as a rough guide for landscaping and gardening, defines 13 zones by annual extreme minimum temperature. It has been adapted by and to other countries (such as Canada) in various forms. Unless otherwise specified, "hardiness zone" or simply "zone" usually refers to the USDA scale. For example, a plant may be described as "hardy to zone 10": this means that the plant can withstand a minimum temperature of −1 °C (30.2 °F) to 3.9 °C (39.0 °F). Other hardiness rating schemes have been developed as well, such as the UK Royal Horticultural Society and US Sunset Western Garden Book systems.

8.6K
04 Nov 2022

Topic Review

Pigmentary and Structural Coloration in Nature

Most of us get inspired by and interact with the world around us based on visual cues such as the colors and patterns that we see. In nature, coloration takes three primary forms: pigmentary coloration, structural coloration, and bioluminescence. Typically, pigmentary and structural coloration are used by animals and plants for their survival. These forms of coloration are enabled by a variety of intracellular biophotonic structures.

8.6K
09 Jun 2022

Topic Review

Home economics, or family and consumer sciences, is a subject concerning human development, personal and family finances, consumer issues, housing and interior design, nutrition and food preparation, as well as textiles and apparel. Home economics courses are offered around the world and across multiple educational levels. Internationally, it is coordinated by the International Federation for Home Economics. Historically, the purpose of these courses was to professionalize housework, to provide intellectual fulfillment for women, and to emphasize the value of "women's work" in society and to prepare them for the traditional roles of sexes. However, it has since evolved into family and consumer sciences to cover additional subject matter outside of just home life and wellness. Family and consumer sciences are taught as an elective or required course in secondary education, as a continuing education course in institutions, and at the primary level. Beginning as home economics in the United States, the course was a key part of the education system for teaching one the art of taking care of a household. In the 19th and early 20th century, it was a woman-dominated course, teaching women to be homemakers and efficient household managers. The American Association of Family and Consumer Sciences was created as an answer to more Americans desiring youth to learn vocational skills. Politics played a role in home economics education, and it wasn’t until later in the century that the course shifted from being woman-dominated to now required for both sexes. Now family and consumer science have been included in the broader subject of Career Technical Education, a program that teaches skilled trades, applied sciences, modern technologies, and career preparation. Despite the subjects over the past century, there has been a major decline in home economics courses offered by educational institutions.

8.6K
09 Nov 2022

Topic Review

Ascorbic Acid-Mediated Reactions

Ascorbic acid is a vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis.

8.6K
25 Nov 2020

Topic Review

Allelopathy is an ecological phenomenon in which organisms interfere with each other. As a management strategy in agricultural systems, allelopathy can be mainly used to control weeds, resist pests, and disease and improve the interaction of soil nutrition and microorganisms. Volatile organic compounds (VOCs) are allelochemicals volatilized from plants and have been widely demonstrated to have different ecological functions.

8.6K
09 Sep 2021

Topic Review

Thermoregulation Strategies in Domestic Animals

Animals adopt several strategies to regulate their body temperature by promoting heat loss or gain in hot and cold environments, respectively. This mechanism of heat loss or production is performed in thermal windows. A thermal window is a structure where many blood capillaries facilitate thermal exchange in this region. The presence of feathers, hair, or glabrous (hairless) skin and their structural characteristics greatly influence each species’ capacity to maintain thermal comfort. This factor needs to be considered when implementing new monitoring or measuring techniques such as infrared thermography since interpretations may vary due to the presence or absence of these structures. It is essential to recognize the effects of glabrous skin, hair, and feathers on thermoregulation to identify species-specific thermal windows that allow accurate evaluations of the thermal state of domestic animals.

8.6K
19 Apr 2022

Topic Review

Transfersomes are elastic in nature, which can deform and squeeze themselves as an intact vesicle through narrow pores that are significantly smaller than its size. Encapsulating the drugs in transfersomes are one of the potential approaches to overcome the barrier function of the skin’s outermost layer. They have a bilayered structure that facilitates the encapsulation of lipophilic and hydrophilic, as well as amphiphilic, drug with higher permeation efficiencies compared to conventional liposomes.

8.6K
23 Sep 2020

Topic Review

Maternal Night-Time Eating During Pregnancy

This narrative review focuses on the contributing factors and health implications of night eating during pregnancy, based on evidence from cross-sectional studies and longitudinal cohorts. The modern lifestyle and presence of pregnancy symptoms contribute to night eating during pregnancy, which is likely to coexist and interact with multiple undesirable lifestyle behaviors. Unfavorable nutritional characteristics associated with night eating have the potential to induce aberrant circadian rhythms in pregnant women, resulting in adverse metabolic and pregnancy outcomes.

8.6K
21 Sep 2020

Topic Review

Pentium FDIV Bug

The Pentium FDIV bug is a hardware bug affecting the floating point unit (FPU) of the early Intel Pentium processors. Because of the bug, the processor might return incorrect binary floating point results when dividing a number. The bug was discovered in 1994 by Professor Thomas R. Nicely at Lynchburg College. Intel attributed the error to missing entries in the lookup table used by the floating-point division circuitry. The severity of the FDIV bug is debated. Though rarely encountered by most users (Byte magazine estimated that 1 in 9 billion floating point divides with random parameters would produce inaccurate results), both the flaw and Intel's initial handling of the matter were heavily criticized by the tech community. In December 1994, Intel recalled the defective processors. In January 1995, Intel announced "a pre-tax charge of $475 million against earnings, ostensibly the total cost associated with replacement of the flawed processors."

8.6K
04 Nov 2022

Topic Review

Nature sports comprise a group of sporting activities that are developed and experienced in natural or rural areas, ranging from formal to informal practices. These practices are performed in a variety of natural contexts including on land (mountain biking, rock-climbing, trekking, etc.), in water (kayaking, sailing, surfing, windsurfing, etc.), and in the air (paragliding and hang-gliding, etc.). Nature sports have a spontaneous, playful nature, "with participation predominantly taking place in informal settings, often without governing bodies or clubs or other forms of external regulation". They are generally autonomous activities, even if some nature sports are practiced collectively, such as kayaking, or those which create sporting sub-cultures, such as in surfing.

8.6K
06 Sep 2021

Topic Review

Spinal Cord Injury

Spinal cord injury (SCI) is a destructive neurological and pathological state that causes major motor, sensory and autonomic dysfunctions. Its pathophysiology comprises acute and chronic phases and incorporates a cascade of destructive events such as ischemia, oxidative stress, inflammatory events, apoptotic pathways and locomotor dysfunctions. This review aims to promote the understanding of SCI pathophysiology, interrelated or interlinked multimolecular interactions and various methods of neuronal recovery i.e., neuroprotective, immunomodulatory and neuro-regenerative pathways and relevant approaches.

8.6K
06 Nov 2020

Topic Review

Essential Oil Prevents COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV‑2), also known as coronavirus disease-2019 (COVID-19), is a pandemic disease that has been declared as modern history’s gravest health emergency worldwide. Until now, no precise treatment modality has been developed. The angiotensin-converting enzyme 2 (ACE2) receptor, a host cell receptor, has been found to play a crucial role in virus cell entry; therefore, ACE2 blockers can be a potential target for anti-viral intervention. In this study, we evaluated the ACE2 inhibitory effects of 10 essential oils. Among them, geranium and lemon oils displayed significant ACE2 inhibitory effects in epithelial cells. In addition, immunoblotting and qPCR analysis also confirmed that geranium and lemon oils possess potent ACE2 inhibitory effects. Furthermore, the gas chromatography-mass spectrometry (GC–MS) analysis displayed 22 compounds in geranium oil and 9 compounds in lemon oil. Citronellol, geraniol, and neryl acetate were the major compounds of geranium oil and limonene that represented major compound of lemon oil. Next, we found that treatment with citronellol and limonene significantly downregulated ACE2 expression in epithelial cells. The results suggest that geranium and lemon essential oils and their derivative compounds are valuable natural anti-viral agents that may contribute to the prevention of the invasion of SARS-CoV-2/COVID-19 into the human body.

8.6K
13 Feb 2021

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