Your browser does not fully support modern features. Please upgrade for a smoother experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Thyroid Function and Suicidal Behavior
Thyroid disease is a very common condition that influences the entire human body, including cognitive function and mental health. As a result, thyroid disease has been associated with multiple neuropsychiatric conditions. However, the relationship between thyroid dysfunction and suicide is still controversial. 
  • 5.6K
  • 28 Jul 2021
Topic Review
List of Doom Source Ports
This article is a list of unofficial source ports of the Doom engine, which was originally used in the video game Doom. Most often, the source ports presented here are modifications made by the Doom community, as opposed to the official Doom versions produced by id Software or affiliated companies. The Doom engine's source code was released to the public on December 23, 1997. Although Doom was originally created for MS-DOS, the original source release was for the subsequent Linux version, due to the use of a proprietary sound library in the DOS version. The original purpose of source ports was cross-platform compatibility, but shortly after the release of the Doom source code, programmers were correcting old, unaddressed Doom bugs and deficiencies in their own source ports, and later on introducing their own modifications to enhance game features and alter gameplay. The source code was originally released under a proprietary license that prohibited commercial use and did not require programmers to provide the source code for the modifications they released in executable form, but it was later re-released on October 3, 1999 under the GNU General Public License after requests from the community.
  • 5.6K
  • 06 Feb 2023
Biography
Hans Albert Einstein
Hans Albert Einstein (/aɪnˈstaɪn, -ˈʃtaɪn/ eyen-STYNE, -⁠SHTYNE; May 14, 1904 – July 26, 1973) was a Swiss-American engineer and educator, the second child and first son of Albert Einstein and Mileva Marić. Hans A. Einstein was a professor of Hydraulic Engineering at the University of California, Berkeley,[1] and was recognized for his research on sediment transport.[2] His papers are
  • 5.6K
  • 27 Dec 2022
Topic Review
Unlawful Combatant
An unlawful combatant, illegal combatant or unprivileged combatant/belligerent is, according to United States law, a person who directly engages in armed conflict in violation of the laws of war and therefore is claimed to not be protected by the Geneva Conventions. The International Committee of the Red Cross points out that the terms "unlawful combatant", "illegal combatant" or "unprivileged combatant/belligerent" are not defined in any international agreements. The Geneva Conventions apply in wars between two or more sovereign states. Article 5 of the Third Geneva Convention states that the status of detainees whose combatant status is in doubt should be determined by a "competent tribunal". Until such time, they must be treated as prisoners of war. After a "competent tribunal" has determined that an individual is not a lawful combatant, the "detaining power" may choose to accord the individual the rights and privileges of a prisoner of war as described in the Third Geneva Convention, but is not required to do so. An individual who is not a lawful combatant, who is not a national of a neutral state, and who is not a national of a co-belligerent state, retains rights and privileges under the Fourth Geneva Convention so that he must be "treated with humanity and, in case of trial, shall not be deprived of the rights of fair and regular trial". While the concept of an unlawful combatant is included in the Third Geneva Convention, the phrase itself does not appear in the document. Article 4 of the Third Geneva Convention does describe categories under which a person may be entitled to POW status. There are other international treaties that deny lawful combatant status for mercenaries and children. In the United States, the Military Commissions Act of 2006 codified the legal definition of this term and invested the U.S. President with broad discretion to determine whether a person may be designated an unlawful enemy combatant under United States law. The assumption that unlawful combatant status exists as a separate category to lawful combatant and civilian is contradicted by the findings of the International Criminal Tribunal for the Former Yugoslavia in the Celebici Judgment. The judgment quoted the 1958 International Committee of the Red Cross (ICRC) commentary on the Fourth Geneva Convention: "Every person in enemy hands must be either a prisoner of war and, as such, be covered by the Third Convention; or a civilian covered by the Fourth Convention. There is no intermediate status; nobody in enemy hands can be outside the law". Thus, anyone not entitled to prisoner of war status maintains the same rights as a civilian, and must be prosecuted under domestic law. Neither status exists in non-international conflict, with all parties equally protected under International Humanitarian Law. The Geneva Conventions do not recognize any status of lawfulness for combatants in conflicts not involving two or more nation states, such as during civil wars between government's forces, and insurgents. A state in such a conflict is legally bound only to observe Common Article 3 of the Geneva Conventions and may ignore all of the other Articles. But each one of them is completely free to apply all or part of the remaining Articles of the Convention.
  • 5.6K
  • 02 Dec 2022
Topic Review
Porous Carbon
Porous carbons are an important class of porous materials that have grown rapidly in recent years. They have the advantages of a tunable pore structure, good physical and chemical stability, a variable specific surface, and the possibility of easy functionalization.   
  • 5.6K
  • 29 Dec 2020
Topic Review
Entrepreneurship in the Sustainable Development Goals
Entrepreneurship plays a prominent and noteworthy role in promoting the Sustainable Development Goals (SDGs). Entrepreneurship, through the creation of new businesses, is recognized as a vital driver in providing employment, reducing inequalities, alleviating poverty, and fostering sustainable growth.
  • 5.6K
  • 18 Feb 2024
Topic Review
Industrial Heritage in Pakistan
Industrial heritage consists of the remains of industrial culture which are of historical, technological, social, architectural, or scientific value. These remains consist of buildings and machinery, workshops, mills and factories, mines and sites for processing and refining, warehouses and stores, places where energy is generated, transmitted, and used, transport and all its infrastructure, as well as places used for social activities related to the industry, such as housing, religious worship or education. The industrial revolution in Pakistan and the major industrial sites and infrastructure of heritage value, such as seaports and railway infrastructure, can be connected to the British rule of the Indian subcontinent. Unlike industrial sites in the Western world, industrial sites in Pakistan are not recognized as heritage sites and are usually ignored by the authorities. They are not currently considered potential sites for future city redevelopment, and the political instruments to offer new programs for such sites are limited.
  • 5.6K
  • 25 May 2022
Topic Review
Intrinsic Self-Healing Polymers
Self-healing polymeric materials have been widely investigated because they can heal the damages spontaneously and thereby prolong their service lifetime. Many ingenious synthetic procedures have been developed for fabricating self-healing polymers with high performance.
  • 5.6K
  • 20 Sep 2022
Topic Review
Spatial Memory
In cognitive psychology and neuroscience, spatial memory is a form of memory responsible for the recording of information about one's environment and spatial orientation. For example, a person's spatial memory is required in order to navigate around a familiar city, just as a rat's spatial memory is needed to learn the location of food at the end of a maze. It is often argued that in both humans and animals, spatial memories are summarized as a cognitive map. Spatial memory has representations within working, short-term memory and long-term memory. Research indicates that there are specific areas of the brain associated with spatial memory. Many methods are used for measuring spatial memory in children, adults, and animals.
  • 5.6K
  • 04 Nov 2022
Topic Review
Understanding Hotel Service Failures
Service failure is inevitable. Service in the hospitality industry involves multiple interactions between the service providers and customers, and a high risk of service failures accompanies these interactions. Although empirical studies on the outcomes and processes of service failures have been conducted in the hotel industry, the findings need more exploration to understand how different segments perceive service failures and the associated emotions differently. This study revealed the similarities and differences between groups (i.e., men vs. women and leisure vs. business) in reporting service failures. Different meanings of words that emerged from the text-mining results were also examined to ensure a more comprehensive understanding of the guest experience.
  • 5.6K
  • 15 Mar 2022
Topic Review
Food Security
Food security is a measure of the availability of food and individuals' ability to access it. Affordability is only one factor. There is evidence of food security being a concern many thousands of years ago, with central authorities in ancient China and ancient Egypt being known to release food from storage in times of famine. At the 1974 World Food Conference the term "food security" was defined with an emphasis on supply. They said food security is the "availability at all times of adequate, nourishing, diverse, balanced and moderate world food supplies of basic foodstuffs to sustain a steady expansion of food consumption and to offset fluctuations in production and prices". Later definitions added demand and access issues to the definition. The final report of the 1996 World Food Summit states that food security "exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life." Household food security exists when all members, at all times, have access to enough food for an active, healthy life. Individuals who are food secure do not live in hunger or fear of starvation. Food insecurity, on the other hand, is defined by the United States Department of Agriculture (USDA) as a situation of "limited or uncertain availability of nutritionally adequate and safe foods or limited or uncertain ability to acquire acceptable foods in socially acceptable ways". Food security incorporates a measure of resilience to future disruption or unavailability of critical food supply due to various risk factors including droughts, shipping disruptions, fuel shortages, economic instability, and wars. In the years 2011–2013, an estimated 842 million people were suffering from chronic hunger. The Food and Agriculture Organization of the United Nations, or FAO, identified the four pillars of food security as availability, access, utilization, and stability. The United Nations (UN) recognized the Right to Food in the Declaration of Human Rights in 1948, and has since said that it is vital for the enjoyment of all other rights. The 1996 World Summit on Food Security declared that "food should not be used as an instrument for political and economic pressure".
  • 5.6K
  • 16 Nov 2022
Topic Review
Maritime Southeast Asia
Maritime Southeast Asia comprises the countries of Brunei, East Timor, Indonesia, Malaysia, the Philippines and Singapore. Maritime Southeast Asia is sometimes also referred to as Island Southeast Asia, Insular Southeast Asia or Oceanic Southeast Asia. The 16th-century term "East Indies" and the later 19th-century term "Malay Archipelago" are also used to refer to Maritime Southeast Asia. In Indonesia and Malaysia, the Old Javanese term "Nusantara" is also used as a synonym for Maritime Southeast Asia. The term, however, is nationalistic and has shifting boundaries. It usually only encompasses the Malay Peninsula, the Sunda Islands, Maluku, and often Western New Guinea and excludes the Philippines . Stretching for several thousand kilometres, the area features a very large number of islands and boasts some of the richest marine, flora and fauna biodiversity on Earth. The main demographic difference that sets Maritime Southeast Asia apart from modern Mainland Southeast Asia is that its population predominantly belongs to Austronesian groups. The region contains some of the world's most highly urbanized areas—Greater Jakarta, Greater Kuala Lumpur, Metro Manila, and Singapore—and yet a majority of islands in this vast region remain uninhabited by humans.
  • 5.6K
  • 28 Nov 2022
Topic Review
Child-Selling
Child-selling is the practice of selling children, usually by parents, legal guardians, or subsequent masters or custodians. After a sale, when the subsequent relationship with the child is essentially non-exploitative, the usual purpose of child-selling is to permit adoption.
  • 5.6K
  • 21 Oct 2022
Topic Review
Peppercorn (Legal)
In legal parlance, a peppercorn is a metaphor for a very small cash payment or other nominal consideration, used to satisfy the requirements for the creation of a legal contract. It is featured in Chappell & Co Ltd v Nestle Co Ltd ( AC 87), which stated that "a peppercorn does not cease to be good consideration if it is established that the promisee does not like pepper and will throw away the corn". What is unusual about the term is that it came into the language when peppercorns were extremely expensive; coming, as they exclusively did, from the Dutch Moluccas. Yet today, the term is more-or-less synonymous with ”a pittance“ — something of minimal value.
  • 5.6K
  • 01 Nov 2022
Topic Review
Bharat Stage Emission Standards
Bharat stage emission standards (BSES) are emission standards instituted by the Government of India to regulate the output of air pollutants from internal combustion engines and Spark-ignition engines equipment, including motor vehicles. The standards and the timeline for implementation are set by the Central Pollution Control Board under the Ministry of Environment & Forests and climate change. The standards, based on European regulations were first introduced in 2000. Progressively stringent norms have been rolled out since then. All new vehicles manufactured after the implementation of the norms have to be compliant with the regulations. Since October 2010, Bharat Stage (BS) III norms have been enforced across the country. In 13 major cities, Bharat Stage IV emission norms have been in place since April 2010 and it has been enforced for entire country since April 2017. In 2016, the Indian government announced that the country would skip the BS-V norms altogether and adopt BS-VI norms by 2020. On November 15, 2017 The Petroleum Ministry of India in consultation with Public Oil Marketing Companies decided to bring forward the date of BS-VI grade auto fuels in NCT of Delhi with effect from April 1, 2018 instead of April 1, 2020. In fact, Petroleum Ministry OMCs were asked to examine the possibility of introduction of BS-VI auto fuels in the whole of NCR area from April 1, 2019. This huge step was taken due the heavy problem of air pollution faced by Delhi which became worse around this year. The decision was met with disarray by the automobile companies as they had planned the development according to roadmap for 2020. The phasing out of 2-stroke engine for two wheelers, the cessation of production of Maruti 800 & introduction of electronic controls have been due to the regulations related to vehicular emissions. While the norms help in bringing down pollution levels, it invariably results in increased vehicle cost due to the improved technology & higher fuel prices. However, this increase in private cost is offset by savings in health costs for the public, as there is lesser amount of disease causing particulate matter and pollution in the air. Exposure to air pollution can lead to respiratory and cardiovascular diseases, which is estimated to be the cause for 6.2 lakh early deaths in 2010, and the health cost of air pollution in India has been assessed at 3% of its GDP.
  • 5.6K
  • 09 Nov 2022
Topic Review
Dry Sanitation Systems
Dry sanitation systems (waterless or composting toilets) have been used since the 1970s. Their use has received acceptance in rural regions of Europe and the United States. Some of the advantages of dry sanitation systems include their waterless nature, their low energy requirement and the creation of fertilizer as an added value product. Moreover, the use of such a system is a sustainable sanitation approach that may reduce the burden on infrastructure and provide sanitation to the 2.5 billion people worldwide who do not currently have access to it. The critical factors when choosing a dry sanitation system and their optimum parameters include aeration, moisture content (50%–60%), temperature (40–65 °C), carbon to nitrogen ratio (25–35), pH (5.5–8.0) and porosity (35%–50%). The temperature–time criterion approach is the most common method used to evaluate the stability and safety of the compost as a fertilizer. The risks of handling the waste after 12 months of composting have been calculated as low.
  • 5.6K
  • 27 Oct 2020
Topic Review
Artificial Intelligence in Water Treatment and Monitoring
Artificial-intelligence methods and machine-learning models have demonstrated their ability to optimize, model, and automate critical water- and wastewater-treatment applications, natural-systems monitoring and management, and water-based agriculture such as hydroponics and aquaponics. In addition to providing computer-assisted aid to complex issues surrounding water chemistry and physical/biological processes, artificial intelligence and machine-learning (AI/ML) applications are anticipated to further optimize water-based applications and decrease capital expenses. Poor data management, low explainability, poor model reproducibility and standardization, as well as a lack of academic transparency are all important hurdles to overcome in order to successfully implement these intelligent applications. Recommendations to aid explainability, data management, reproducibility, and model causality are offered in order to overcome these hurdles and continue the successful implementation of these powerful tools. 
  • 5.6K
  • 01 Jul 2022
Topic Review
Metal Sulfide Precipitation
Metal sulfide precipitation can efficiently recover several metals and metalloids from different aqueous sources, including wastewaters and hydrometallurgical solutions. 
  • 5.6K
  • 04 Jan 2022
Topic Review
Compounds of Oxygen
The oxidation state of oxygen is −2 in almost all known compounds of oxygen. The oxidation state −1 is found in a few compounds such as peroxides. Compounds containing oxygen in other oxidation states are very uncommon: −​1⁄2 (superoxides), −​1⁄3 (ozonides), 0 (elemental, hypofluorous acid), +​1⁄2 (dioxygenyl), +1 (dioxygen difluoride), and +2 (oxygen difluoride). Oxygen is reactive and will form oxides with all other elements except the noble gases helium, neon, argon, and krypton.
  • 5.6K
  • 26 Oct 2022
Topic Review
Aloe vera
Aloe vera plant offers a sustainable solution for the removal of various pollutants from water. Due to its chemical composition, Aloe vera has been explored as coagulant/flocculant and biosorbent for water treatment. 
  • 5.6K
  • 23 Jun 2021
  • Page
  • of
  • 2794
Featured Entry Collections
>>

Featured Reprints

>>
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Medieval Royal Iconography
Academic Video Service
Feedback

Quick Survey

Encyclopedia MDPI is conducting a targeted survey to identify the specific barriers hindering efficient research. We invite you to spend 3 minutes defining the priorities for our next generation of structured knowledge tools.
Take Survey