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
Applications of Carbon Dots
Although there is significant progress in the research of carbon dots (CDs), some challenges such as difficulty in large-scale synthesis, complicated purification, low quantum yield, ambiguity in structure-property correlation, electronic structures, and photophysics are still major obstacles that hinder the commercial use of CDs. The unique properties of CDs, such as good biocompatibility, high photostability, excellent light-harvesting, up-conversion, effective electron transfer, and bandgap narrowing, make the CDs promising nanomaterials for applications in many fields. 
  • 2.7K
  • 25 Aug 2022
Topic Review
Prognostic Biomarkers in Patients with Acute Myocardial Infarction
Despite all the important advances in its diagnosis and treatment, acute myocardial infarction (AMI) is still one of the most prominent causes of morbidity and mortality worldwide. Early identification of patients at high risk of poor outcomes through the measurement of various biomarker concentrations might contribute to more accurate risk stratification and help to guide more individualized therapeutic strategies, thus improving prognoses. 
  • 2.7K
  • 01 Sep 2022
Topic Review
Fossil Fuels Lobby
"Fossil fuels lobby" is a term used to label the paid representatives of large fossil fuel (oil, gas, coal) and electric utilities corporations who attempt to influence governmental policy. So-called Big Oil companies such as ExxonMobil, Royal Dutch Shell, BP, Total S.A., Chevron Corporation, and ConocoPhillips are amongst the largest corporations associated with the fossil fuels lobby. General Electric, Southern Company, First Energy, and the Edison Electric Institute are also among the most influential electric utilities corporations. By sector, "Energy/Nat Resource" comes fifth, behind "Misc Business", "Finance/Insur/RealEst", Health and "Communic/Electronics".
  • 2.7K
  • 27 Oct 2022
Topic Review
Vascular Endothelial Dysfunction-Related Disease
Oxidative stress and chronic inflammation play an important role in the pathogenesis of atherosclerosis. Atherosclerosis develops as the first step of vascular endothelial dysfunction induced by complex molecular mechanisms. Vascular endothelial dysfunction leads to oxidative stress and inflammation of vessel walls, which in turn enhances vascular endothelial dysfunction. Vascular endothelial dysfunction and vascular wall oxidative stress and chronic inflammation make a vicious cycle that leads to the development of atherosclerosis.
  • 2.7K
  • 03 Feb 2023
Topic Review
Euphorbia
Euphorbia genus (Euphorbiaceae family), which is the third largest genus of angiosperm plants comprising ca. 2000 recognized species, is used all over the world in traditional medicine, especially in the traditional Chinese medicine. Members of this taxa are promptly recognizable by their specialized inflorescences and latex. In this review, an overview of Euphorbia-derived natural products such as essential oils, extracts, and pure compounds, active in a broad range of biological activities, and with potential usages in health maintenance, is described. The chemical composition of essential oils from Euphorbia species revealed the presence of more than 80 phytochemicals, mainly oxygenated sesquiterpenes and sesquiterpenes hydrocarbons, while Euphorbia extracts contain secondary metabolites such as sesquiterpenes, diterpenes, sterols, flavonoids, and other polyphenols. 
  • 2.7K
  • 26 Jul 2021
Topic Review
Waterlogging Impacts on Crop Growth
Waterlogging has the greatest impact on photosynthesis, followed by phenology and leaf expansion, suggesting a need for improved equations linking waterlogging to carbon assimilation. In agricultural fields, soil waterlogging can occur for many reasons. These may include excessive rainfall or irrigation, poor soil drainage, rising or perched water tables, as well as lateral surface or subsurface flows. This may lead to reduced oxygen within soil pores, causing reduced growth and, sometimes, crop death. 
  • 2.7K
  • 06 Sep 2022
Topic Review
Adenoids and Tonsils: Immune System's Tireless Gatekeepers
Within the intricate realm of the mucosal immune system resides a captivating duo: the adenoids (or pharyngeal tonsils) and the tonsils (including palatine, tubal, and lingual variations), which harmoniously form the Waldeyer’s ring. As they are strategically positioned at the crossroads of the respiratory and gastrointestinal systems, these exceptional structures fulfill a vital purpose. They function as formidable “gatekeepers” by screening microorganisms—both bacteria and viruses—with the mission to vanquish local pathogens via antibody production. However, under specific circumstances, their function can take an unsettling turn, inadvertently transforming them into reservoirs for pathogen incubation.
  • 2.7K
  • 28 Jun 2023
Topic Review
Different Nerve-Sparing Techniques during Radical Prostatectomy
Nerve-sparing technique during RP has a major impact to both oncological and functional outcomes of the procedure and various different techniques have been developed aiming to optimize its outcomes. Nerve-sparing techniques can be distinguished based on the fascial planes of dissection (intrafascial, interfascial or extrafascial), the direction of dissection (retrograde or antegrade), the timing of the neurovascular bundle dissection off the prostate (early vs. late release), the use of cautery, the application of traction and the number of the neurovascular bundles which are preserved.
  • 2.7K
  • 18 Apr 2022
Topic Review
4D Scanning Transmission Electron Microscopy
4D scanning transmission electron microscopy (4D STEM) is a subset of scanning transmission electron microscopy (STEM) which utilizes a pixelated electron detector to capture a convergent beam electron diffraction (CBED) pattern at each scan location. This technique captures a 2 dimensional reciprocal space image associated with each scan point as the beam rasters across a 2 dimensional region in real space, hence the name 4D STEM. Its development was enabled by evolution in STEM detectors and improvements computational power. The technique has applications in visual diffraction imaging, phase orientation and strain mapping, phase contrast analysis, among others. The name 4D STEM is common in literature, however it is known by other names: 4D STEM EELS, ND STEM (N- since the number of dimensions could be higher than 4), position resolved diffraction (PRD), spatial resolved diffractometry, momentum-resolved STEM, "nanobeam precision electron diffraction", scanning electron nano diffraction, nanobeam electron diffraction, or pixelated STEM.
  • 2.7K
  • 11 Oct 2022
Topic Review
C1 and P1 (Neuroscience)
The C1 and P1 (also called the P100) are two human scalp-recorded event-related brain potential (event-related potential (ERP)) components, collected by means of a technique called electroencephalography (EEG). The C1 is named so because it was the first component in a series of components found to respond to visual stimuli when it was first discovered. It can be a negative-going component (when using a mastoid reference point) or a positive going component with its peak normally observed in the 65–90 ms range post-stimulus onset. The P1 is called the P1 because it is the first positive-going component (when also using a mastoid reference point) and its peak is normally observed in around 100 ms. Both components are related to processing of visual stimuli and are under the category of potentials called visually evoked potentials (VEPs). Both components are theorized to be evoked within the visual cortices of the brain with C1 being linked to the primary visual cortex (striate cortex) of the human brain and the P1 being linked to other visual areas (Extrastriate cortex). One of the primary distinctions between these two components is that, whereas the P1 can be modulated by attention, the C1 has been typically found to be invariable to different levels of attention.
  • 2.7K
  • 14 Oct 2022
Topic Review
Chromogenic Technologies for Energy Saving
Chromogenic materials and devices include a wide range of technologies that are capable of changing their spectral properties according to specific external stimuli. Several studies have shown that chromogenics can be conveniently used in building façades in order to reduce energy consumption, with other significant effects. First of all, chromogenics influence the annual energy balance of a building, achieving significant reductions in consumption for HVAC and artificial lighting. In addition, these technologies potentially improve the indoor level of visual comfort, reducing the risks of glare and excessive lighting. 
  • 2.7K
  • 19 Dec 2020
Topic Review
Shellshock (Software Bug)
Shellshock, also known as Bashdoor, is a family of security bugs in the Unix Bash shell, the first of which was disclosed on 24 September 2014. Shellshock could enable an attacker to cause Bash to execute arbitrary commands and gain unauthorized access to many Internet-facing services, such as web servers, that use Bash to process requests. On 12 September 2014, Stéphane Chazelas informed Bash's maintainer Chet Ramey of his discovery of the original bug, which he called "Bashdoor". Working with security experts, Mr. Chazelas developed a patch (fix) for the issue, which by then had been assigned the vulnerability identifier CVE-2014-6271. The existence of the bug was announced to the public on 2014-09-24, when Bash updates with the fix were ready for distribution. The bug Chazelas discovered caused Bash to unintentionally execute commands when the commands are concatenated to the end of function definitions stored in the values of environment variables. Within days of its publication, a variety of related vulnerabilities were discovered (CVE-2014-6277, CVE-2014-6278, CVE-2014-7169, CVE-2014-7186 and CVE-2014-7187). Ramey addressed these with a series of further patches. Attackers exploited Shellshock within hours of the initial disclosure by creating botnets of compromised computers to perform distributed denial-of-service attacks and vulnerability scanning. Security companies recorded millions of attacks and probes related to the bug in the days following the disclosure. Because of the potential to compromise millions of unpatched systems, Shellshock was compared to the Heartbleed bug in its severity.
  • 2.7K
  • 18 Nov 2022
Topic Review
University of Florida Taser Incident
The University of Florida Taser incident was an incident in which a University of Florida student was stunned with a taser at a forum featuring then U.S. Senator John Kerry. On September 17, 2007, Kerry addressed a Constitution Day forum at the University of Florida campus in Gainesville, which was organized by the ACCENT Speakers Bureau, an agency of the university's student government. Andrew Meyer, a 21-year-old fourth-year undergraduate mass communication student, had initially been allowed to ask a question after the close of the question period. He asked Kerry whether he was a member of Skull and Bones, as George W. Bush is, implying that Kerry did not contest Bush's presidency because of their shared affiliation. Meyer was forcibly pulled away from the microphone. He was immediately restrained and forcibly removed and was subsequently arrested by university police. During his arrest, Meyer struggled and screamed for help. While six officers held Meyer down, one of the officers drive-stunned him with a taser following Meyer's shouted plea to the police, "Don't tase me, bro!" Several videos of the episode were posted on the Web, with one version reaching 7 million views on YouTube. The New Oxford American Dictionary listed tase or taze as one of the words of the year for 2007, popularized by the widespread use of the phrase. Meyer registered the phrase as a trademark in September 2007.
  • 2.7K
  • 23 Nov 2022
Topic Review
Ceiling Effects: The Example of IQ 276
The ceiling effect in psychometrics refers to loss of score differentiation at the upper end of a test’s range. In intelligence testing, ceiling effects hinder valid assessment of profoundly gifted individuals because scores cluster at or near the maximums of widely used instruments (e.g., WAIS, Stanford–Binet). This entry defines the ceiling effect in IQ measurement, summarizes common upper limits and the development of extended norms, and outlines methodological responses such as high-range instruments, item response theory (IRT), and model-based statistical extrapolation. Using the debated “IQ 276” (SD = 24; ≈ 210 on SD = 15, z ≈ +7.33) purely as an illustrative case, it reviews promises and pitfalls of inferring extreme ability beyond a test’s empirical range. The goal is not to adjudicate any individual claim but to clarify the psychometric challenges of measuring extreme intelligence and to sketch directions for building valid, higher-ceiling assessments.
  • 2.7K
  • 25 Aug 2025
Topic Review
Application of Plant Waxes in Edible Coatings
Natural waxes are of plant or animal origin. They are resistant to moisture, oxidation, and microbiological decomposition. Plant waxes of commercial and industrial importance are obtained from various plant species and are used to produce cosmetic products, ink, varnishes, luster, candles, pastels, etc. Some of them are used in the composition of some edible coatings applied to various foodstuffs. By using them, the properties and quality of food products are preserved during storage.
  • 2.7K
  • 15 Jun 2023
Topic Review
Friction Stir Welding
Friction stir welding is a method of materials processing that enables the joining of similar and dissimilar materials. The process, as originally designed by The Welding Institute (TWI), provides a unique approach to manufacturing—where materials can be joined in many designs and still retain mechanical properties that are similar to, or greater than, other forms of welding. This process is not free of defects that can alter, limit, and occasionally render the resulting weld unusable. 
  • 2.7K
  • 17 Dec 2021
Topic Review
People with Intellectual Disability in Nigeria
Intellectual disability (ID) is an emerging field of research in Nigeria. According to Maulik et al., the highest prevalence of people with an intellectual disability (ID) are seen in low- and middle-income countries (LMIC). In 2018, the World Health Organization estimated that 29 million people in Nigeria were living with a disability. Nigeria signed the United Convention on the Rights of Persons with Disabilities (UNCRPD) and ratified its optional Protocol in 2010—an attempt to protect the rights of disabled people and, in January 2019, passed the Discrimination Against Persons with Disabilities (Prohibition) Act 2018.
  • 2.7K
  • 06 Sep 2022
Topic Review
Disk Defragmenter (Windows)
Disk Defragmenter is a utility in Microsoft Windows designed to increase access speed by rearranging files stored on a disk to occupy contiguous storage locations, a technique called defragmentation. Defragmenting a disk minimizes head travel, which reduces the time it takes to read files from and write files to the disk. Beginning with Windows XP, Disk Defragmenter also reduces system startup times. From Windows 8, the program was renamed to Defragment and Optimize Drives.
  • 2.7K
  • 31 Oct 2022
Topic Review Peer Reviewed
Labor Market Institutions and Employment
The role of labor market institutions and policies has received great attention throughout the history of labor economics. Labor market institutions are responsible for a wide range of policies, regulations, and organizations that affect the labor market, though their impact on employment can vary depending on the specific institutions and the economic context across countries. This entry attempts to provide an overview of five main labor market institutions and policies, i.e., the minimum wage, employment protection, the power of unions, active labor market policies, and unemployment insurance/unemployment benefits. It also presents theoretical expectations of their effects on employment outcomes and collates relevant results from the related literature, focusing mainly on the most recent empirical evidence. Finally, this entry provides insights regarding labor market institutions and offers proposals for shaping the labor market landscape.
  • 2.7K
  • 19 Feb 2024
Topic Review
Cyclodextrins in the Food Industry
Cyclodextrins (CDs) are cyclic oligomers broadly used in food manufacturing as food additives for different purposes, e.g., to improve sensorial qualities, shelf life, and sequestration of components.
  • 2.7K
  • 04 Mar 2021
  • Page
  • of
  • 2727
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