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Topic Review
Protection Motivation Theory
Protection motivation theory (PMT) was originally created to help understand individual human responses to fear appeals. Protection motivation theory proposes that people protect themselves based on two factors: threat appraisal and coping appraisal. Threat appraisal assesses the severity of the situation and examines how serious the situation is, while coping appraisal is how one responds to the situation. Threat appraisal consists of the perceived severity of a threatening event and the perceived probability of the occurrence, or vulnerability. Coping appraisal consists of perceived response efficacy, or an individual's expectation that carrying out the recommended action will remove the threat, and perceived self efficacy, or the belief in one's ability to execute the recommended courses of action successfully. PMT is one model that explains why people engage in unhealthy practices and offers suggestions for changing those behaviors. It is educational and motivational. Primary prevention: taking measures to combat the risk of developing a health problem. (e.g., controlling weight to prevent high blood pressure). Secondary prevention: taking steps to prevent a condition from becoming worse. (e.g., remembering to take daily medication to control blood pressure). Another psychological model that describes self-preservation and processing of fear is terror management theory.
  • 14.1K
  • 09 Oct 2022
Topic Review
History of Wind Power
Wind power has been used as long as humans have put sails into the wind. For more than two millennia wind-powered machines have ground grain and pumped water. Wind power was widely available and not confined to the banks of fast-flowing streams, or later, requiring sources of fuel. Wind-powered pumps drained the polders of the Netherlands, and in arid regions such as the American mid-west or the Australian outback, wind pumps provided water for livestock and steam engines. With the development of electric power, wind power found new applications in lighting buildings remote from centrally-generated power. Throughout the 20th century parallel paths developed small wind plants suitable for farms or residences, and larger utility-scale wind generators that could be connected to electricity grids for remote use of power. Today wind-powered generators operate in every size range between tiny plants for battery charging at isolated residences, up to near-gigawatt sized offshore wind farms that provide electricity to national electrical networks. By 2014, over 240,000 commercial-sized wind turbines were operating in the world, producing 4% of the world's electricity.
  • 14.1K
  • 02 Oct 2022
Topic Review
Fedora Version History
Fedora is a popular Linux distribution developed by the community-supported Fedora Project and is sponsored by Red Hat. Fedora attempts to maintain a six-month release schedule, offering new versions in May and November, although some releases have experienced minor delays.
  • 14.1K
  • 28 Oct 2022
Topic Review
New Vrindaban, West Virginia
New Vrindaban is an unincorporated area and an ISKCON (Hare Krishna) intentional community located in Marshall County, West Virginia, United States, near Moundsville. The town consists of 1,204 acres (4.87 km2) (of which 0.1 km² is of water), and several building complexes, homes, apartment buildings, and businesses including the Sri Sri Radha Vrindaban Chandra Temple (RVC Temple) and Prabhupada's Palace of Gold. New Vrindaban was founded in 1968 under the direct guidance of A.C. Bhaktivedanta Swami Prabhupada, founder of ISKCON, by his disciple Kirtanananda Swami. It is named for the Indian city of Vrindavan.
  • 14.1K
  • 11 Nov 2022
Topic Review
Hydrogen as an Alternative Fuel
Hydrogen is a very important fuel of our secure and clean energy future. Hydrogen will be the fuel of the future and gradually it will replace all current fossil fuels. Hydrogen can be used as a fuel for vehicles, to heat homes and offices, to produce electricity, and to fuel ships and aircraft. The present work provides an overview of hydrogen as an alternative fuel, which can be used in internal combustion engines and in fuel cells.
  • 14.1K
  • 27 Oct 2020
Topic Review
Outer Space
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.
  • 14.1K
  • 26 Oct 2022
Topic Review
Armenia
Armenia, officially the Republic of Armenia, is a landlocked country in the Armenian Highlands of Eastern Europe. Due to its location in the South Caucasus, Armenia is sometimes described as transcontinental, spanning both Eastern Europe and Western Asia. It is bordered by Turkey to the west, Georgia to the north, the Lachin corridor (under a Russian peacekeeping force) and Azerbaijan to the east, and Iran and the Azerbaijani exclave of Nakhchivan to the south. Yerevan is the capital and largest city. Armenia is a unitary, multi-party, democratic nation-state with an ancient cultural heritage. The first Armenian state of Urartu was established in 860 BC, and by the 6th century BC it was replaced by the Satrapy of Armenia. The Kingdom of Armenia reached its height under Tigranes the Great in the 1st century BC and in the year 301 became the first state in the world to adopt Christianity as its official religion, The ancient Armenian kingdom was split between the Byzantine and Sasanian Empires around the early 5th century. Under the Bagratuni dynasty, the Bagratid Kingdom of Armenia was restored in the 9th century. Declining due to the wars against the Byzantines, the kingdom fell in 1045 and Armenia was soon after invaded by the Seljuk Turks. An Armenian principality and later a kingdom Cilician Armenia was located on the coast of the Mediterranean Sea between the 11th and 14th centuries. Between the 16th and 19th centuries, the traditional Armenian homeland composed of Eastern Armenia and Western Armenia came under the rule of the Ottoman and Persian empires, repeatedly ruled by either of the two over the centuries. By the 19th century, Eastern Armenia had been conquered by the Russian Empire, while most of the western parts of the traditional Armenian homeland remained under Ottoman rule. During World War I, 1.5 million Armenians living in their ancestral lands in the Ottoman Empire were systematically exterminated in the Armenian genocide. In 1918, following the Russian Revolution, all non-Russian countries declared their independence after the Russian Empire ceased to exist, leading to the establishment of the First Republic of Armenia. By 1920, the state was incorporated into the Transcaucasian Socialist Federative Soviet Republic, and in 1922 became a founding member of the Soviet Union. In 1936, the Transcaucasian state was dissolved, transforming its constituent states, including the Armenian Soviet Socialist Republic, into full Union republics. The modern Republic of Armenia became independent in 1991 during the dissolution of the Soviet Union. Armenia is a developing country and ranks 81st on the Human Development Index (2018). Its economy is primarily based on industrial output and mineral extraction. While Armenia is geographically located in the South Caucasus, it is generally considered geopolitically European. Since Armenia aligns itself in many respects geopolitically with Europe, the country is a member of numerous European organizations including the Council of Europe, the Eastern Partnership, Eurocontrol, the Assembly of European Regions, and the European Bank for Reconstruction and Development. Armenia is also a member of certain regional groups throughout Eurasia, including the Asian Development Bank, the Collective Security Treaty Organization, the Eurasian Union, and the Eurasian Development Bank. Armenia supports the de facto independent Artsakh, which was proclaimed in 1991. Armenia also recognises the Armenian Apostolic Church, the world's oldest national church, as the country's primary religious establishment. The unique Armenian alphabet was created by Mesrop Mashtots in 405 AD.
  • 14.1K
  • 10 May 2023
Topic Review
Germplasm Conservation
Germplasm is a valuable natural resource that provides knowledge about the genetic composition of a species and is crucial for conserving plant diversity. Germplasm protection strategies not only involve rescuing plant species threatened with extinction, but also help preserve all essential plants, on which rests the survival of all organisms. The successful use of genetic resources necessitates their diligent collection, storage, analysis, documentation, and exchange. Slow growth cultures, cryopreservation, pollen and DNA banks, botanical gardens, genetic reserves, and farmers’ fields are a few germplasm conservation techniques being employed. However, the adoption of in-vitro techniques with any chance of genetic instability could lead to the destruction of the entire substance, but the improved understanding of basic regeneration biology would, in turn, undoubtedly increase the capacity to regenerate new plants, thus expanding selection possibilities. Germplasm conservation seeks to conserve endangered and vulnerable plant species worldwide for future proliferation and development; it is also the bedrock of agricultural production. 
  • 14.0K
  • 25 Jun 2021
Topic Review
Straight-Six Engine
The straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is an internal combustion engine, with six cylinders mounted in a straight line along the crankcase with all the pistons driving a common crankshaft (straight engine). The bank of cylinders may be oriented at any angle, and where the bank is inclined away from the vertical, the engine is sometimes called a slant-six (although this is also a Chrysler-specific design). The straight-six layout is the simplest engine layout that possesses both primary and secondary mechanical engine balance, resulting in much less vibration than engines with fewer cylinders.
  • 14.0K
  • 15 Nov 2022
Topic Review
Drainpipe Materials through the Centuries
Agricultural drainage plays an important role worldwide in food production and conservation of soil resources, while safeguarding investments in agricultural production and irrigation projects. It can improve crop yields and land productivity, especially on poorly drained soils and in cases of prolonged waterlogging. Both the subsurface drainage materials and the installation techniques used have a long history dating to prehistoric times. Over time, new subsurface drainage materials, installation techniques and modernized equipment developed continuously to take advantage of technological advances provided through research and development, while the planning and organization of the implementation process improved.
  • 14.0K
  • 27 Oct 2020
Topic Review
Solar Symbol
A solar symbol is a symbol representing the Sun. Common solar symbols include circles (with or without rays), crosses, and spirals. In religious iconography, personifications of the Sun or solar attributes are often indicated by means of a halo or a radiate crown. When the systematic study of comparative mythology first became popular in the 19th century, scholarly opinion tended to over-interpret historical myths and iconography in terms of "solar symbolism". This was especially the case with Max Müller and his followers beginning in the 1860s in the context of Indo-European studies. Many "solar symbols" claimed in the 19th century, such as the swastika, triskele, Sun cross, etc. have tended to be interpreted more conservatively in scholarship since the later 20th century.
  • 14.0K
  • 25 Oct 2022
Topic Review
State-Dependent Memory
State-dependent memory or state-dependent learning is the phenomenon through which memory retrieval is most efficient when an individual is in the same state of consciousness as they were when the memory was formed. The term is often used to describe memory retrieval while in states of consciousness produced by psychoactive drugs – most commonly, alcohol, but has implications for mood or non-substance induced states of consciousness as well. Unlike context-dependent memory, which involves an individual's external environment and conditions, state-dependent memory applies to the individual's internal conditions. For example, while context-dependent memory might refer to the idea that taking a test in the same room that an individual studied in will make it easier to retrieve those memories, state-dependent learning refers to the idea that if an individual always studied for a test while slightly caffeinated, it will most likely be easiest to recall what they studied during the test if they are at a similar level of caffeination.
  • 14.0K
  • 24 Oct 2022
Topic Review
Misogyny in Horror Films
Misogyny can occur in horror films when there is a degrading representation of women. This is found particularly in slasher films, where there is often gendered specific violence towards women. Female characters experience violence and brutality at the hands of male antagonists far more often than male characters in these films. Female characters are likely to experience sexual violence, particularly in the rape-and-revenge subgenre.
  • 13.9K
  • 28 Nov 2022
Topic Review
Flood Prediction Using ML Models
Floods are among the most destructive natural disasters, which are highly complex to model. The research on the advancement of flood prediction models contributed to risk reduction, policy suggestion, minimization of the loss of human life, and reduction of the property damage associated with floods. To mimic the complex mathematical expressions of physical processes of floods, during the past two decades, machine learning (ML) methods contributed highly in the advancement of prediction systems providing better performance and cost-effective solutions. Due to the vast benefits and potential of ML, its popularity dramatically increased among hydrologists.Researchers through introducing novel ML methods and hybridizing of the existing ones aim at discovering more accurate and efficient prediction models. The main contribution of this paper is to demonstrate the state of the art of ML models in flood prediction and to give insight into the most suitable models. In this paper, the literature where ML models were benchmarked through a qualitative analysis of robustness, accuracy, effectiveness, and speed are particularly investigated to provide an extensive overview on the various ML algorithms used in the field. The performance comparison of ML models presents an in-depth understanding of the different techniques within the framework of a comprehensive evaluation and discussion. As a result, this paper introduces the most promising prediction methods for both long-term and short-term floods. Furthermore, the major trends in improving the quality of flood prediction models are investigated. Among them, hybridization, data decomposition, algorithm ensemble, and model optimization are reported as the most effective strategies for the improvement of ML methods. This survey can be used as a guideline for hydrologists as well as climate scientists in choosing the proper ML method according to the prediction task.
  • 13.9K
  • 04 Jan 2023
Topic Review
Agricultural Production in Qatar
Starting in the 1970s, Qatar had almost entirely based its economic growth on resource exploitation of the hydrocarbon sector, with agriculture being considered only as a ‘’hobby’’, rather than an important economic activity. The real driver of change affecting Qatar’s agricultural sector is the issue of food security, after the 2017 embargo (imposed by neighboring countries that made Qatar’s government critically aware that it cannot rely on other countries to secure its food basket), and thus highlighted the need to produce in the country.The factor that has most hindered the development of productive agricultural and horticultural systems in the past has been the availability of land, with suitable soils. This is a consequence of Qatar’s harsh climate; it is in a hot arid zone characterized by sparse precipitation; high summer temperatures; together with high humidity in the late summer months that makes working outside very difficult; very high solar radiation; strong winds; and limited freshwater availability for irrigation causing dependency on desalinated abstracted groundwater, and/or (more recently) on desalinated sea-water.
  • 13.9K
  • 24 Apr 2021
Topic Review
New Seismotectonic Atlas of Greece
Integration and harmonization of the most recent seismological, geological, tectonic, geophysical and geodetic datasets, with the aim of capturing the potential of ground deformation towards a more reliable evaluation of seismic risk at a national level.
  • 13.9K
  • 20 Nov 2020
Topic Review
Guava Leaves
Psidium guajava (L.) belongs to the Myrtaceae family and it is an important fruit in tropical areas like India, Indonesia, Pakistan, Bangladesh, and South America. The leaves of the guava plant have been studied for their health benefits which are attributed to their plethora of phytochemicals, such as quercetin, avicularin, apigenin, guaijaverin, kaempferol, hyperin, myricetin, gallic acid, catechin, epicatechin, chlorogenic acid, epigallocatechin gallate, and caffeic acid. Extracts from guava leaves (GLs) have been studied for their biological activities, including anticancer, antidiabetic, antioxidant, antidiarrheal, antimicrobial, lipid-lowering, and hepatoprotection activities.
  • 13.9K
  • 14 Apr 2021
Topic Review
Water Quality Index
A critical water quality index (WQI) method has been used to determine the overall water quality status of surface water and groundwater systems globally since the 1960s. WQI follows four steps: parameter selection, sub-indices, establishing weights, and final index aggregation.
  • 13.9K
  • 09 Apr 2021
Topic Review
Physical Properties of Food Materials
The physical properties of food materials have defined those properties that can only be measured by physical means rather than chemical means. Food materials are basically naturally occurring biological-originated raw materials that have their own exclusive physical identity that makes them unique in nature. Due to the uniqueness of their physical properties, to properly measure the different physical characteristics of any food materials to get control and understand about the changes in their native physical characteristics with the influence of time-temperature-processing-treatment-exposure, proper measurement techniques for various physical properties of food materials are required with numerous desired outputs.
  • 13.8K
  • 25 Feb 2022
Topic Review
GAZ Tigr
The GAZ Tigr (Russian: Тигр and English: Tiger) is a Russia n 4x4, multipurpose, all-terrain infantry mobility vehicle manufactured by GAZ, first delivered to the Russian Army in 2006. Primarily used by the Russian Federation's armed forces, it is also used by numerous other countries.
  • 13.8K
  • 26 Oct 2022
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