Search | Encyclopedia MDPI

Your browser does not fully support modern features. Please upgrade for a smoother experience.

Subject:

Sort by:

Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)

Filter:

All Topic Review Biography Peer Reviewed Entry Video Entry

Topic Review

Genetically Modified Food Controversies

Genetically modified food controversies are disputes over the use of foods and other goods derived from genetically modified crops instead of conventional crops, and other uses of genetic engineering in food production. The disputes involve consumers, farmers, biotechnology companies, governmental regulators, non-governmental organizations, and scientists. The key areas of controversy related to genetically modified food (GM food or GMO food) are whether such food should be labeled, the role of government regulators, the objectivity of scientific research and publication, the effect of genetically modified crops on health and the environment, the effect on pesticide resistance, the impact of such crops for farmers, and the role of the crops in feeding the world population. In addition, products derived from GMO organisms play a role in the production of ethanol fuels and pharmaceuticals. Specific concerns include mixing of genetically modified and non-genetically modified products in the food supply, effects of GMOs on the environment, the rigor of the regulatory process, and consolidation of control of the food supply in companies that make and sell GMOs. Advocacy groups such as the Center for Food Safety, Organic Consumers Association, Union of Concerned Scientists, and Greenpeace say risks have not been adequately identified and managed, and they have questioned the objectivity of regulatory authorities. The safety assessment of genetically engineered food products by regulatory bodies starts with an evaluation of whether or not the food is substantially equivalent to non-genetically engineered counterparts that are already deemed fit for human consumption. No reports of ill effects have been documented in the human population from genetically modified food. There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case basis before introduction. Nonetheless, members of the public are much less likely than scientists to perceive GM foods as safe. The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation.

15.8K
08 Oct 2022

Topic Review

E-government (short for electronic government) is the use of electronic communications devices, computers and the Internet to provide public services to citizens and other persons in a country or region. According to Jeong, 2007 the term consists of the digital interactions between a citizen and their government (C2G), between governments and other government agencies (G2G), between government and citizens (G2C), between government and employees (G2E), and between government and businesses/commerces (G2B). E-government delivery models can be broken down into the following categories: This interaction consists of citizens communicating with all levels of government (city, state/province, national, and international), facilitating citizen involvement in governance using information and communication technology (ICT) (such as computers and websites) and business process re-engineering (BPR). Brabham and Guth (2017) interviewed the third party designers of e-government tools in North America about the ideals of user interaction that they build into their technologies, which include progressive values, ubiquitous participation, geolocation, and education of the public. Other definitions are more away from technology as an object, to see them simply as facilitators or instruments and focus on specific changes in Public Administration issues, and in the internal transformation of a Government, is the case of the definition that established the specialist technologist Mauro D. Ríos in the paper "In search of a definition of Electronic Government", he says: "Digital Government is a new way of organization and management of public affairs, introducing positive transformational processes in management and the structure itself of the organization chart, adding value to the procedures and services provided, all through the introduction and continued appropriation of information and communication technologies as a facilitator of these transformations."

15.8K
08 Nov 2022

Topic Review

Single Point Mooring (SPM) Systems with Buoys

The SPM system consists of four main components, namely, the body of the buoy, the anchoring and mooring components, the fluid transfer system and the ancillary elements. Static legs linked to the seabed underneath the surface keep the buoy body in place. Above the water level, the body has a spinning portion that is attached to the offloading/loading tanker. A roller bearing, referred to as the main bearing, connects these two portions. Due to this array, the anchored tanker can easily weather-vane around the buoy and find a steady position. The concept of the buoy is determined by the type of bearing utilized and the divide between the rotating and geostatic sections. The buoy’s size is determined by the amount of counter buoyancy required to keep the anchor chains in place, and the chains are determined by environmental conditions and vessel size.

15.7K
19 Nov 2021

Topic Review

Blonde Stereotype

Blonde stereotypes are stereotypes of blond-haired women. Sub-types include the "blonde bombshell" and the "dumb blonde". Blondes are differently stereotyped from brunettes as more desirable and less intelligent. There are many blonde jokes made on these premises. Although chiefly aimed at women, jokes of this style have also been aimed at similar stereotypes associated with men, such as the "dumb jock" and the "surfer dude".

15.7K
25 Oct 2022

Topic Review

Ge'ez (/ˈɡiːɛz/; ግዕዝ, Gəʿəz Template:IPA-gez; also transliterated Gi'iz) is an ancient South Semitic language of the Ethiosemitic branch. The language originates from the region encompassing northern Ethiopia and southern Eritrea in the Horn of Africa. Today, Ge'ez is used only as the main language of liturgy of the Ethiopian Orthodox Tewahedo and Eritrean Orthodox Tewahedo churches, the Ethiopian and Eritrean Catholic churches, and the Beta Israel Jewish community. However, in Ethiopia, Amharic or other local languages, and in Eritrea and Ethiopia's Tigray Region, Tigrinya may be used for sermons. Amharic, Tigrinya, and Tigre are closely related to Ge'ez. The closest living languages to Ge'ez are Tigre and Tigrinya with lexical similarity at 71% and 68%, respectively. Some linguists do not believe that Ge'ez constitutes a common ancestor of modern Ethiosemitic languages, but that Ge'ez became a separate language early on from another hypothetical unattested language, which can be seen as an extinct sister language of Amharic, Tigre and Tigrinya. The foremost Ethiopian experts such as Amsalu Aklilu point to the vast proportion of inherited nouns that are unchanged, and even spelled identically in both Ge'ez and Amharic (and to a lesser degree, Tigrinya).

15.7K
17 Nov 2022

Topic Review

Energy Management Strategy

A Comprehensive Review on Classification, Energy Management Strategy, and Control Algorithm for Hybrid Electric Vehicles

15.7K
22 Oct 2020

Topic Review

Upper Mantle (Earth)

The upper mantle of the Earth begins just beneath the crust about 35 km (22 mi) and ends at the top of the lower mantle at 670 km (420 mi). Temperatures range from approximately 200 °C (392 °F) at the upper boundary with the crust to approximately 900 °C (1,650 °F) at the boundary with the lower mantle. Upper mantle material which has come up onto the surface is made up of about 55% olivine, 35% pyroxene and 5 to 10% of calcium oxide and aluminum oxide minerals such as plagioclase, spinel or garnet, depending upon depth.

15.6K
29 Sep 2022

Topic Review

Computational Chemistry Methods

The main objective of computational chemistry is to solve chemical problems by simulating chemical systems (molecular, biological, materials) in order to provide reliable, accurate and comprehensive information at an atomic level. To this end, there are two main methodological families: those based on quantum chemical methods and those based on molecular mechanics. The former are methods in which the electrons are explicitly accounted for, while in the latter their presence is hidden in the force field.

15.6K
17 Jun 2021

Topic Review

The Apostolic Age of the history of Christianity is traditionally regarded as the period of the Twelve Apostles, dating from the Great Commission of the Apostles by the risen Jesus in Jerusalem around 33 AD until the death of the last Apostle, believed to be John the Apostle in Anatolia c. 100. Traditionally, the Apostles are believed to have dispersed from Jerusalem, founding the Apostolic Sees. It holds special significance in Christian tradition as the age of the direct apostles of Jesus Christ. One major primary source for the "Apostolic Age" is the Acts of the Apostles, but its historical accuracy is questioned by some and its coverage is partial, focusing especially from Acts 15:36 onwards on the ministry of Paul (an apostle to the Gentiles, but not one of the original twelve apostles – Rom. 1:1; 11:13) and his companions, and ending around 62 AD with Paul preaching in Rome under house arrest. According to most scholars, the followers of Jesus were composed principally from apocalyptic Jewish sects during the late Second Temple period of the 1st century. Some Early Christian groups were strictly Jewish, such as the Ebionites and the early-church leaders in Jerusalem, collectively called Jewish Christians. During this period, they were led by James the Just. According to Acts 9:1–2, they described themselves as 'disciples of the Lord' and [followers] 'of the Way', and according to Acts 11:26 a settled community of disciples at Antioch were the first to be called 'Christians'. Saul of Tarsus, commonly known as Paul the Apostle, persecuted the early Jewish Christians, such as Saint Stephen, then converted and adopted the title of "Apostle to the Gentiles" and started proselytizing among the Gentiles. He persuaded the leaders of the Jerusalem Church to allow Gentile converts exemption from most Jewish commandments at the Council of Jerusalem. According to the Oxford Dictionary of the Christian Church, Paul's influence on Christian thinking is more significant than any other New Testament author, however the relationship of Paul the Apostle and Judaism is still disputed today (see the link for details). After the Destruction of the Second Temple in AD 70 during the First Jewish-Roman War, or at the latest following the Bar Kokhba revolt of 132, Jerusalem ceased to be the center of the Christian church, and its bishops became "suffragans" (subordinates) of the Metropolitan bishop of Caesarea. In the 2nd century, Christianity established itself as a predominantly Gentile religion that spanned the Roman Empire and beyond.

15.6K
27 Oct 2022

Topic Review

Mercedes-Benz 9G-Tronic Transmission

9G-Tronic is Mercedes-Benz's trademark name for its nine-speed automatic transmission, starting off with the W9A 700 (Wandler-9-Gang-Automatik bis 700 Nm Eingangsdrehmoment; converter-9-gear-automatic with 516 lb-ft maximum input torque; type 725.0) as core model.

15.5K
30 Nov 2022

Topic Review

History of Islam

The history of Islam concerns the political, social, economic and cultural developments of the Islamic civilization. Despite concerns about the reliability of early sources, most historians believe that Islam originated in Mecca and Medina at the start of the 7th century, approximately 600 years after the founding of Christianity. Muslims, however, believe that it did not start with Muhammad, but that it was the original faith of others whom they regard as prophets, such as Jesus, David, Moses, Abraham, Noah and Adam. In 610 CE, Muhammad began receiving what Muslims consider to be divine revelations. Muhammad's message won over a handful of followers and was met with increasing opposition from Meccan notables. In 618, after he lost protection with the death of his influential uncle Abu Talib, Muhammad migrated to the city of Yathrib (now known as Medina). With Muhammad's death in 632, disagreement broke out over who would succeed him as leader of the Muslim community which was eventually resurrected leading to the First Fitna. The dispute would intensify greatly after the Battle of Karbala, in which Muhammad's grandson Hussein ibn Ali was killed by the ruling Umayyad Caliph Yazid I, and the outcry for revenge divided the early Islamic community. By the 8th century, the Islamic empire extended from Iberia in the west to the Indus river in the east. Polities such as those ruled by the Umayyads (in the Middle East and later in Iberia), Abbasids, Fatimids, and Mamluks were among the most influential powers in the world. The Islamic Golden Age gave rise to many centers of culture and science and produced notable astronomers, mathematicians, doctors and philosophers during the Golden Age of Islam. In the early 13th century, the Delhi Sultanate took over northern parts of Indian subcontinent. In the 13th and 14th centuries, destructive Mongol invasions from the East, along with the loss of population in the Black Death, greatly weakened the traditional centers of the Islamic world, stretching from Persia to Egypt, but in the Early Modern period, the Ottomans, the Safavids, and the Mughals were able to create new world powers again. During the 19th and early 20th centuries, most parts of the Muslim world fell under the influence or direct control of European "Great Powers." Their efforts to win independence and build modern nation states over the course of the last two centuries continue to reverberate to the present day.

15.5K
11 Nov 2022

Topic Review

Longitudinal Static Stability

In flight dynamics, longitudinal static stability is the stability of an aircraft in the longitudinal, or pitching, plane under steady flight conditions. This characteristic is important in determining whether a human pilot will be able to control the aircraft in the pitching plane without requiring excessive attention or excessive strength.

15.5K
20 Oct 2022

Topic Review

Apple juice fermentation process

This work emphasized the apple fermentation process and showed how the fermentation can be affected by the first material composition and the used microorganisms.

15.5K
19 Aug 2020

Topic Review

Hindu Views on Evolution

Hinduism includes a range of viewpoints about the origin of life, creationism and evolution. There is no single story of creation, due to dynamic diversity of Hinduism, and these are derived from various sources like Vedas, some from the Brahmanas, some from Puranas; some are philosophical, based on concepts, and others are narratives. The Rigveda mentions the Hiranyagarbha ("golden embryo") as the source of the creation of the Universe, similar to the world egg motif found in the creation myths of many other civilizations. It also contains a myth of proto-Indo-European origin, in which the creation arises out of the dismemberment of a cosmic being (the Purusha) who is sacrificed by the gods. As for the creation of the primordial gods themselves, the Nasadiya Sukta of Rigveda takes a near-agnostic stand, stating that the Gods came into being after the world's creation, and nobody knows when the world first came into being. In the later Puranic texts, the creator god Brahma is described as performing the act of 'creation', or more specifically of 'propagating life within the universe'. Some texts consider him equivalent to the Hiranyagarbha or the Purusha, while others state that he arose out of these. Brahma is a part of the trinity of gods that also includes Vishnu and Shiva, who are responsible for 'preservation' and 'destruction' (of the universe) respectively. Many Hindu texts mention the cycle of creation and destruction. The Shatapatha Brahmana states that the current human generation descends from Manu, the only man who survived a great deluge after being warned by the God. This legend is comparable to the other flood legends, such as the story of the Noah's Ark mentioned in the Bible and the Quran. Hindus find support for, or foreshadowing of evolutionary ideas in scriptures. For example, the concept of Dashavatara can be seen as having some similarities to Charles Darwin's theory of evolution.The first incarnation of Vishnu in the form of a fish resembles the evolutionary origin of fish in the Silurian Period. In a survey of 909 people, 77% of its respondents in India agreed that enough scientific evidence exists to support Charles Darwin’s Theory of Evolution, and 85% of God-believing people said they agree with evolution as well. According to the survey conducted by Pew Forum in the United States , 80% of Hindus agree that evolution is the best explanation for the origin of human life on earth. However, in India, there were minimal references to Darwinism in the 1800s. Elements of Victorian England opposed the idea of Darwinism. Hindus already had present notion of common ancestry between humans and animals. The Hindu dharma believes that the gods have animal features, showing a theory that humans can be reborn again as animals or with their features.

15.5K
21 Oct 2022

Topic Review

Sciences and societies are increasing their demands of contributions from social theorists. International programs of research strengthen now the priorities of social impact and co-creation. Social impact means the presentation of evidence that scientific studies are contributing to social improvements, for instance, oriented to the UN Sustainable Development Goals; in order to develop and evaluate social impact, all sciences need the dialogue and collaboration of social theories. Co-creation means to create knowledge through dialogue between scientists and citizens, what also needs social theories. This demand is generating an increasing relevance of those social theories able to make these contributions, most of them, elaborated by networks and teams of different individuals from diverse disciplines. Traditional social theories created in the 19th and 20th centuries, mostly developed by individuals, provided important elements that are now included in the new theoretical process.

15.5K
22 Dec 2020

Topic Review

List of Highest Mountains on Earth

There are at least 108 mountains on Earth with elevations of 7,200 metres (23,622 ft) or greater above sea level. The vast majority of these mountains are located on the edge of the Indian and Eurasian plate- namely, in China , Pakistan , Nepal and India .

15.5K
10 Nov 2022

Topic Review

Elephant in the Room

Elephant in the room is an English-language metaphorical idiom for an obvious problem or risk that no one wants to discuss. It is based on the idea/thought that something as conspicuous as an elephant can appear to be overlooked in codified social interactions, and that the sociology/psychology of repression also operates on the macro scale.

15.4K
28 Oct 2022

Topic Review

Muhammad Ibn Musa Al-Khwarizmi

Muḥammad ibn Mūsā al-Khwārizmī (Persian: محمد بن موسی خوارزمی‎, romanized: Moḥammad ben Musā Khwārazmi; c. 780 – c. 850), or al-Khwarizmi and formerly Latinized as Algorithmi, was a Persian polymath who produced vastly influential works in mathematics, astronomy, and geography. Around 820 CE he was appointed as the astronomer and head of the library of the House of Wisdom in Baghdad.:14 Al-Khwarizmi's popularizing treatise on algebra (The Compendious Book on Calculation by Completion and Balancing, c. 813–833 CE:171) presented the first systematic solution of linear and quadratic equations. One of his principal achievements in algebra was his demonstration of how to solve quadratic equations by completing the square, for which he provided geometric justifications.:14 Because he was the first to treat algebra as an independent discipline and introduced the methods of "reduction" and "balancing" (the transposition of subtracted terms to the other side of an equation, that is, the cancellation of like terms on opposite sides of the equation), he has been described as the father or founder of algebra. The term algebra itself comes from the title of his book (the word al-jabr meaning "completion" or "rejoining"). His name gave rise to the terms algorism and algorithm, as well as Spanish and Portuguese terms algoritmo, and Spanish guarismo and Portuguese algarismo meaning "digit". In the 12th century, Latin translations of his textbook on arithmetic (Algorithmo de Numero Indorum) which codified the various Indian numerals, introduced the decimal positional number system to the Western world. The Compendious Book on Calculation by Completion and Balancing, translated into Latin by Robert of Chester in 1145, was used until the sixteenth century as the principal mathematical text-book of European universities. In addition to his best-known works, he revised Ptolemy's Geography, listing the longitudes and latitudes of various cities and localities.:9 He further produced a set of astronomical tables and wrote about calendaric works, as well as the astrolabe and the sundial. He also made important contributions to trigonometry, producing accurate sine and cosine tables, and the first table of tangents.

15.4K
10 Oct 2022

Topic Review Video

Fixed and Floating Offshore Structures

Diverse forms of offshore oil and gas structures are utilized for a wide range of purposes and in varying water depths. They are designed for unique environments and water depths around the world. The applications of these offshore structures require different activities for proper equipment selection, design of platform types, and drilling/production methods. There are advances made in ocean engineering which include a variety of innovative offshore structure designs, ranging from fixed platforms to floating platforms. Some of these structures include the deep-water semisubmersible platforms, jack-up rigs, floating offshore wind turbines (FOWTs), FPS (floating production systems) units.

15.4K
19 Aug 2022

Topic Review

Outer space, or simply space, is the expanse that exists beyond the Earth and between celestial bodies. Outer space is not completely empty—it is a hard vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is 2.7 kelvins (−270.45 °C; −454.81 °F). The plasma between galaxies accounts for about half of the baryonic (ordinary) matter in the universe; it has a number density of less than one hydrogen atom per cubic metre and a temperature of millions of kelvins. Local concentrations of matter have condensed into stars and galaxies. Studies indicate that 90% of the mass in most galaxies is in an unknown form, called dark matter, which interacts with other matter through gravitational but not electromagnetic forces. Observations suggest that the majority of the mass-energy in the observable universe is dark energy, a type of vacuum energy that is poorly understood. Intergalactic space takes up most of the volume of the universe, but even galaxies and star systems consist almost entirely of empty space. Outer space does not begin at a definite altitude above the Earth's surface. However, the Kármán line, an altitude of 100 km (62 mi) above sea level, is conventionally used as the start of outer space in space treaties and for aerospace records keeping. The framework for international space law was established by the Outer Space Treaty, which entered into force on 10 October 1967. This treaty precludes any claims of national sovereignty and permits all states to freely explore outer space. Despite the drafting of UN resolutions for the peaceful uses of outer space, anti-satellite weapons have been tested in Earth orbit. Humans began the physical exploration of space during the 20th century with the advent of high-altitude balloon flights. This was followed by manned rocket flights and, then, manned Earth orbit, first achieved by Yuri Gagarin of the Soviet Union in 1961. Due to the high cost of getting into space, manned spaceflight has been limited to low Earth orbit and the Moon. On the other hand, unmanned spacecraft have reached all of the known planets in the Solar System. Outer space represents a challenging environment for human exploration because of the hazards of vacuum and radiation. Microgravity also has a negative effect on human physiology that causes both muscle atrophy and bone loss. In addition to these health and environmental issues, the economic cost of putting objects, including humans, into space is very high.

15.4K
26 Oct 2022

Page
of
2798

Featured Entry Collections

>>

Featured Reprints

>>

Encyclopedia of Digital Society, Industry 5.0 and Smart City

Encyclopedia of Digital Society, Industry 5.0 and Smart City
Chief Editor: Sandro Serpa

Encyclopedia of Engineering

Encyclopedia of Social Sciences

Encyclopedia of Social Sciences
Chief Editor: Kum Fai Yuen

Encyclopedia of Medieval Royal Iconography

Encyclopedia of Medieval Royal Iconography
Published Version (2022) >>
Chief Editor: Mirko Vagnoni

Academic Video Service

Feedback

Top