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Topic Review

Names of the Days of the Week

The names of the days of the week in many languages are derived from the names of the classical planets in Hellenistic astrology, which were in turn named after contemporary deities, a system introduced by the Roman Empire during Late Antiquity. In some other languages, the days are named after corresponding deities of the regional culture, either beginning with Sunday or with Monday. In the international standard ISO 8601, Monday is treated as the first day of the week.

52.2K
01 Nov 2022

Topic Review

MDPI is a pioneer in scholarly open access publishing, supporting academic communities since 1996. Based in Basel, Switzerland, MDPI’s mission is to foster open scientific exchange in all forms, across all disciplines. Its 283 diverse, peer-reviewed, open access journals are supported by more than 35,500 academic editors. MDPI serves scholars from around the world to ensure that the latest research is freely available, and all content is distributed under a Creative Commons Attribution License (CC BY).

49.9K
17 Jan 2022

Topic Review

The concept of Industry 4.0 is often associated with the fourth industrial revolution industrial, given the profound implications for the productive paradigm. But what exactly is Industry 4.0? Industry 4.0 emerged in Germany in 2011, with the aim of increasing the competitiveness of German industry. In short, it applied digital technologies to production, in a close association between economy and digital technology, resulting in innovation through the integration between the real and the virtual world (Cyber-Physical Systems) in industrial activity and production.

49.5K
15 Feb 2022

Topic Review

Now I Lay Me Down to Sleep

Now I lay me down to sleep is a classic children's bedtime prayer from the 18th century.

48.7K
14 Oct 2022

Topic Review

Polar Moment of Inertia

The polar moment (of inertia), also known as second (polar) moment of area, is a quantity used to describe resistance to torsional deformation (deflection), in cylindrical (or non-cylindrical) objects (or segments of an object) with an invariant cross-section and no significant warping or out-of-plane deformation. It is a constituent of the second moment of area, linked through the perpendicular axis theorem. Where the planar second moment of area describes an object's resistance to deflection (bending) when subjected to a force applied to a plane parallel to the central axis, the polar second moment of area describes an object's resistance to deflection when subjected to a moment applied in a plane perpendicular to the object's central axis (i.e. parallel to the cross-section). Similar to planar second moment of area calculations ([math]\displaystyle{ I_x }[/math],[math]\displaystyle{ I_y }[/math], and [math]\displaystyle{ I_{xy} }[/math]), the polar second moment of area is often denoted as [math]\displaystyle{ I_z }[/math]. While several engineering textbooks and academic publications also denote it as [math]\displaystyle{ J }[/math] or [math]\displaystyle{ J_z }[/math], this designation should be given careful attention so that it does not become confused with the torsion constant, [math]\displaystyle{ J_t }[/math], used for non-cylindrical objects. Simply put, the polar moment of inertia is a shaft or beam's resistance to being distorted by torsion, as a function of its shape. The rigidity comes from the object's cross-sectional area only, and does not depend on its material composition or shear modulus. The greater the magnitude of the polar moment of inertia, the greater the torsional resistance of the object.

48.5K
14 Nov 2022

Topic Review

Harut and Marut

Harut and Marut (Arabic: هَارُوْت وَمَارُوْت) are two angels mentioned in Quran 2:102, who are said to have been located in Babylon. According to some narratives, those two angels were in the time of Idris. The Quran indicates that they were a trial for the people and through them the people were tested with sorcery. The story itself parallels a Jewish legend about the fallen angels Shemḥazaī, ʿUzza, and ʿAzaʾel. The names Hārūt and Mārūt appear to be etymologically related to those of Haurvatat and Ameretat, two Zoroastrian archangels. Haurvatat-Ameretat (Pahlavi hrwdʼd ʼmwrdʼd) appears in Sogdian language texts as hrwwt mrwwt. A relationship to Armenian hawrot mawrot has been suggested but is not confirmed. Muslim sources disagree, whether Harut and Marut can be considered fallen angels or not.

47.5K
15 Nov 2022

Topic Review

List of the Named Buddhas

In countries where Theravāda Buddhism is practiced by the majority of people, such as Sri Lanka, Cambodia, Laos, Myanmar, Thailand, it is customary for Buddhists to hold elaborate festivals, especially during the fair weather season, paying homage to the 29 Buddhas described in the Buddhavamsa. The Buddhavamsa is a text which describes the life of Gautama Buddha and the 27 Buddhas who preceded him, along with the future Metteyya Buddha. The Buddhavamsa is part of the Khuddaka Nikāya, which in turn is part of the Sutta Piṭaka. The Sutta Piṭaka is one of three main sections of the Pāli Canon of Theravāda Buddhism. The first three of these Buddhas—Taṇhaṅkara, Medhaṅkara, and Saraṇaṅkara—lived before the time of Dīpankara Buddha. The fourth Buddha, Dīpankara, is especially important, as he was the Buddha who gave niyatha vivarana (prediction of future Buddhahood) to the Brahmin youth who would in the distant future become the bodhisattva Gautama Buddha. After Dīpankara, 25 more noble people (ariya-puggala) would attain enlightenment before Gautama, the historical Buddha. Many Buddhists also pay homage to the future (and 29th) Buddha, Maitreya. According to Buddhist scripture, Maitreya will be a successor of Gautama who will appear on Earth, achieve complete enlightenment, and teach the pure Dharma. The prophecy of the arrival of Maitreya is found in the canonical literature of all Buddhist sects (Theravada, Mahayana, and Vajrayana), and is accepted by most Buddhists as a statement about an event that will take place when the Dharma will have been forgotten on Jambudvipa (the terrestrial realm, where ordinary human beings live).

47.4K
22 Nov 2022

Topic Review

Organizational Culture

Organizational culture may be considered as the shared way of being, thinking and acting in a collective of coordinated people with reciprocal expectations; it is shaped, disseminated, learned and changed over time, providing some predictability in every organization.

46.5K
30 Oct 2020

Topic Review

Contemporary Society

Contemporary society, according to social and political scientists, is characterised by at least three fundamental directions: These are some examples, but they are many more. These presentations are the result of a number of fundamental changes that are irreversibly transforming our daily lives, our way of thinking and perceiving the world and our way of living together. Among these fundamental changes are: improvements in life conditions, life expectancy, literacy and gender equality; changes in domestic and international political institutions; and the breakdown of natural equilibria.

45.7K
30 Sep 2022

Topic Review

The Principalía or noble class was the ruling and usually educated upper class in the pueblos of the Spanish Philippines, comprising the gobernadorcillo (who had functions similar to a town mayor), and the cabezas de barangay (heads of the barangays) who governed the districts. The distinction or status of being part of the principalía was a hereditary right. However, it could also be acquired, as attested by the royal decree of 20 December 1863 (signed in the name of Queen Isabella II by the Minister of the Colonies, José de la Concha). p1 cols 1–4 This distinguished upper class was exempted from tribute (tax) to the Spanish crown during the colonial period. Colonial documents would refer to them as "de privilegio y gratis", in contrast to those who pay tribute ("de pago"). It was the true aristocracy and the true nobility of colonial Philippines, which could be roughly comparable to the patrician class of ancient Rome. The principales (members of the principalía) traced their origin from the pre‑colonial royal and noble class of Datu of the established kingdoms, rajahnates, confederacies, and principalities,(p19) as well as the lordships of the smaller ancient social units called barangays in Visayas, Luzon, and Mindanao. The members of this class enjoyed exclusive privileges: only the members of the principalía were allowed to vote, be elected to public office, and be addressed by the title: Don or Doña.(p624)(p218) The use of the honorific addresses "Don" and "Doña" was strictly limited to what many documents during the colonial period would refer to as "vecinas y vecinos distinguidos". For the most part, the social privileges of the nobles were freely acknowledged as befitting their greater social responsibilities. The gobernadorcillo during that period received a nominal salary and was not provided government funds for public services. In fact more often the gobernadorcillo had to maintain government of his municipality by looking after the post office and the jailhouse, and by managing public infrastructure, using personal resources.(p326)(p294) Principales also provided assistance to parishes by helping in the construction of church buildings, and in the pastoral and religious activities of the priests who, being usually among the few Spaniards in most colonial towns, had success in winning the goodwill of the natives. More often, the clergy were the sole representatives of Spain in many parts of the archipelago. Under the Patronato Real of the Spanish crown, these Spanish churchmen were also the king's effective ambassadors, and promoters of the realm.(p726-727;735) With the end of Spanish sovereignty over the Philippines after the Spanish–American War in 1898 and the introduction of a democratic, republican system during the American Occupation, the Principalía and their descendants lost their legal authority and social privileges. Many were, however, able to integrate into the new socio-political structure, retaining some degree of influence and power.

44.1K
28 Sep 2022

Topic Review

Theories on Addiction of Smartphone and Internet

Excessive use of smartphones has been associated with a number of negative consequences for individuals. Some of these consequences relate to many symptoms of behavioral addiction. Addiction is defined as a pleasure-inducing behavior that through repeated exposure gradually leads to loss of control and further negative consequences.

43.9K
24 Jun 2022

Topic Review

Cinnamon, Clove and Cumin against Urinary Tract Infections

Spices are aromatic plants widely used in Mexico to flavor, color, or preserve food. In particular, the Food and Drug Administration (FDA) Organization defined spices as: “whole, broken or ground aromatic vegetable substances, whose significant function in food is to flavor rather than to nourish”. Most of the beneficial health properties of spices are mediated through the direct action of their phytochemicals, especially polyphenols or polyphenol degradation products. These phytochemicals have broad antioxidant properties and target specific receptors or enzymes involved in various anti-inflammatory pathways or immune responses. Phenolic acids and flavonoids, especially flavones and flavonoids, are spices’ predominant class of polyphenols. Furthermore, the antimicrobial properties of spices are attributed to their unique volatile oils and oleoresins. Because spices are obtained from aromatic plants and herbs, they are generally considered safe (GRAS).

43.8K
28 Apr 2023

Topic Review

The reuse of built agricultural/industrial heritage has been a common practice worldwide. These structures represent excellent symbols of the great agricultural/industrial past. These agricultural/hydro-technologies also serve as monuments of socio-cultural identities, especially in rural areas and on small farms. One example of a successful application of agricultural technologies for small farms is the water mill. By harnessing the water energy, they were used for traditional flour and other goods production (e.g., olive oil) and works requiring energy, with the main role in the evolution of the traditional/cultural landscape. Water mills have been used to drive a mechanical process of milling, hammering, and rolling and are a portion of the agricultural, cultural, and industrial heritage.

43.6K
17 Mar 2023

Topic Review

Social Conflict

Social conflict refers to the tension, disagreement, or antagonism between individuals or groups within a society arising from opposing interests, values, or actions. It is a fundamental concept in sociology, highlighting the role of power, resources, and societal structures in shaping conflicts that can range from interpersonal disputes to large-scale social movements.

43.6K
26 Jan 2024

Topic Review

Sustainability Literacy

Sustainability is an increasingly central concept, both in social practice and in scientific, economic and even political fields. The promotion of sustainability literacy is critical in enabling informed civic participation.

43.1K
04 Apr 2021

Topic Review

Kulam or Barang are terms used for a kind of black magic, specifically a malevolent use of sympathetic magic, which is associated with Indigenous Philippine religions and practiced in the Philippines . Kulam has been present throughout the Philippines before the Spanish colonization. Today it is said to be centered in Pampanga, Talalora, Western Samar and Sorsogon, where many of the country's faith healers reside. Kulam also exists in many of the hinterlands, especially in Samar and Leyte, however, Kulam is known and occurs anywhere in the Philippines.

42.6K
08 Oct 2022

Topic Review

Information and Communication Technologies for Development

Information and communication technologies for development (ICT4D) refers to the application of information and communication technologies (ICT) toward social, economic, and political development, with a particular emphasis on helping poor and marginalized people and communities. It aims to help in international development by bridging the digital divide and providing equitable access to technologies. ICT4D is grounded in the notions of "development", "growth", "progress" and "globalization" and is often interpreted as the use of technology to deliver a greater good. Another similar term used in the literature is "digital development". ICT4D draws on theories and frameworks from many disciplines, including sociology, economics, development studies, library, information science, and communication studies.

42.6K
24 Oct 2022

Topic Review

Parasitic Nutrition

Parasitic nutrition is a mode of heterotrophic nutrition where a parasitic organism lives on the body surface or inside the body of another type of organism (a host) and gets nutrition directly from the body of the host. Since these parasites derive nourishment from their host, this symbiotic interaction is often harmful to the host. Parasites depend on their host for survival, since the host provides nutrition and protection. As a result of this dependence, parasites have considerable modifications to optimise parasitic nutrition and therefore their survival. Parasites are divided into two groups: endoparasites and ectoparasites. Endoparasites are parasites that live inside the body of the host, whereas ectoparasites are parasites that live on the outer surface of the host and generally attach themselves during feeding. Due to the different strategies of endoparasites and ectoparasites, they require different adaptations to derive nutrients from their host. Parasites require nutrients to carry out essential functions including reproduction and growth. Essentially, the nutrients required from the host are carbohydrates, amino acids and lipids. Carbohydrates are utilised to generate energy, whilst amino acids and fatty acids are involved in the synthesis of macromolecules and the production of eggs. Most parasites are heterotrophs, so they therefore are unable to synthesise their own 'food' i.e. organic compounds and must acquire these from their host.

42.3K
29 Nov 2022

Topic Review

Language Acquisition

Language acquisition is the process by which humans acquire the capacity to perceive and comprehend language (in other words, gain the ability to be aware of language and to understand it), as well as to produce and use words and sentences to communicate. Language acquisition involves structures, rules and representation. The capacity to successfully use language requires one to acquire a range of tools including phonology, morphology, syntax, semantics, and an extensive vocabulary. Language can be vocalized as in speech, or manual as in sign. Human language capacity is represented in the brain. Even though human language capacity is finite, one can say and understand an infinite number of sentences, which is based on a syntactic principle called recursion. Evidence suggests that every individual has three recursive mechanisms that allow sentences to go indeterminately. These three mechanisms are: relativization, complementation and coordination. There are two main guiding principles in first-language acquisition: speech perception always precedes speech production and the gradually evolving system by which a child learns a language is built up one step at a time, beginning with the distinction between individual phonemes. Linguists who are interested in child language acquisition for many years question how language is acquired, Lidz et al. states "The question of how these structures are acquired, then, is more properly understood as the question of how a learner takes the surface forms in the input and converts them into abstract linguistic rules and representations." Language acquisition usually refers to first-language acquisition, which studies infants' acquisition of their native language, whether that be spoken language or signed language as a result of prelingual deafness, though it can also refer to bilingual first language acquisition (BFLA), which refers to an infant's simultaneous acquisition of two native languages. This is distinguished from second-language acquisition, which deals with the acquisition (in both children and adults) of additional languages. In addition to speech, reading and writing a language with an entirely different script compounds the complexities of true foreign language literacy. Language acquisition is one of the quintessential human traits, because non-humans do not communicate by using language.

42.0K
18 Nov 2022

Topic Review

Quetzalcoatl (/ˌkɛtsɑːlkoʊˈɑːtəl/; Spanish: [ket͡salˈkoatʊl] (listen); Template:Lang-nci-IPA, in honorific form: Quetzalcohuātzin, modern Nahuatl pronunciation (help·info)) is a deity in Mesoamerican culture and literature whose name comes from the Nahuatl language and means "feathered serpent" or "Quetzal-feathered Serpent". The earliest known documentation of the worship of a Feathered Serpent occurs in Teotihuacan in the first century BC or first century AD. That period lies within the Late Preclassic to Early Classic period (400 BC – 600 AD) of Mesoamerican chronology; veneration of the figure appears to have spread throughout Mesoamerica by the Late Classic period (600–900 AD). In the Postclassic period (900–1519 AD), the worship of the feathered-serpent deity centred in the primary Mexican religious center of Cholula. In this period the deity is known to have been named "Quetzalcoatl" by his Nahua followers. In the Maya area he was approximately equivalent to Kukulkan and Gukumatz, names that also roughly translate as "feathered serpent" in different Mayan languages. Quetzalcoatl, the Aztec god of wind, air, and learning, wears around his neck the "wind breastplate" ehecailacocozcatl, "the spirally voluted wind jewel" made of a conch shell. This talisman was a conch shell cut at the cross-section and was likely worn as a necklace by religious rulers, as such objects have been discovered in burials in archaeological sites throughout Mesoamerica, and potentially symbolized patterns witnessed in hurricanes, dust devils, seashells, and whirlpools, which were elemental forces that had significance in Aztec mythology. Codex drawings pictured both Quetzalcoatl and Xolotl wearing an ehecailacocozcatl around the neck. Additionally, at least one major cache of offerings includes knives and idols adorned with the symbols of more than one god, some of which were adorned with wind jewels. In the era following the 16th-century Spanish conquest of the Aztec Empire, a number of records conflated Quetzalcoatl with Ce Acatl Topiltzin, a ruler of the mythico-historic city of Tollan. Historians debate to what degree, or whether at all, these narratives about this legendary Toltec ruler describe historical events. Furthermore, early Spanish sources written by clerics tend to identify the god-ruler Quetzalcoatl of these narratives with either Hernán Cortés or Thomas the Apostle— identifications which have also become sources of a diversity of opinions about the nature of Quetzalcoatl. Among the Aztecs, whose beliefs are the best-documented in the historical sources, Quetzalcoatl was related to gods of the wind, of the planet Venus, of the dawn, of merchants and of arts, crafts and knowledge. He was also the patron god of the Aztec priesthood, of learning and knowledge. Quetzalcoatl was one of several important gods in the Aztec pantheon, along with the gods Tlaloc, Tezcatlipoca and Huitzilopochtli. Two other gods represented by the planet Venus are Quetzalcoatl's ally Tlaloc (the god of rain), and Quetzalcoatl's twin and psychopomp, Xolotl. Animals thought to represent Quetzalcoatl include resplendent quetzals, rattlesnakes (coatl meaning "serpent" in Nahuatl), crows, and macaws. In his form as Ehecatl he is the wind, and is represented by spider monkeys, ducks, and the wind itself. In his form as the morning star, Venus, he is also depicted as a harpy eagle. In Mazatec legends the astrologer deity Tlahuizcalpantecuhtli, who is also represented by Venus, bears a close relationship with Quetzalcoatl.

41.3K
11 Oct 2022

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