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Topic Review
Khat
Khat (Catha edulis) is a recreational, chewed herbal drug that has been used as a psychostimulant for centuries in East Africa and the Arabian Peninsula, namely in Somalia, Ethiopia, and Yemen. However, the growing worldwide availability of khat has produced widespread concern. The plant comprises a large number of active substances, among which cathinone, cathine, and norephedrine are the main constituents, which can be included in the group of sympathomimetics of natural origin. In fact, these compounds are amphetamine analogues, and, as such, they have amphetamine-like nervous system stimulant effects. Chewing the leaves gives people a sensation of well-being and increases energy, alertness, and self-confidence. The chronic use of khat is, however, associated with severe cardiac, neurological, psychological, and gastrointestinal complications. The psychological dependence and withdrawal symptoms of khat are the reasons for its prolonged use.
  • 3.4K
  • 18 Feb 2022
Topic Review
Medicinal Value of Chicory
Cichorium intybus L., commonly named chicory, is a perennial herbal plant of the dandelion family Asteraceae, mainly seen with bright blue flowers, and seldom pink or white. Generally distributed in Asia and Europe, all the plants’ parts were traditionally used in medicinal preparations due to their considerable contents of antioxidant phytochemicals thought to have a beneficial impact in preventing and treating various illnesses such as fever, diarrhea, jaundice, and gallstones. Different chicory types are grown for their salad leaves, chicons, or roots, and regularly used for inulin extraction, for preparing coffee substitutes, or for feeding livestock. This entry is based on a literature review and highlights the beneficial and therapeutic action of chicory extracts and their confirmed or hypothesized mechanism of action in diabetes, hepatic disorders, and cardiovascular disease, as indicated by the results of in vivo and in vitro studies, on cell lines, human and animal models.
  • 3.4K
  • 10 May 2021
Topic Review
Pudu (Genus)
The pudus (Mapudungun püdü or püdu, Spanish: pudú, Spanish pronunciation: [puˈðu]) are two species of South American deer from the genus Pudu, and are the world's smallest deer. The name is a loanword from Mapudungun, the language of the indigenous Mapuche people of central Chile and south-western Argentina. The two species of pudus are the northern pudu (Pudu mephistophiles) from Venezuela, Colombia, Ecuador, and Peru, and the southern pudu (Pudu puda; sometimes incorrectly modified to Pudu pudu) from southern Chile and south-western Argentina . Pudus range in size from 32 to 44 centimeters (13 to 17 in) tall, and up to 85 centimeters (33 in) long. The southern pudu is currently classified as near threatened, while the northern pudu is classified as Data Deficient in the IUCN Red List.
  • 3.4K
  • 20 Oct 2022
Topic Review
Innovation-Driven Strategy on High-Quality Economic Development
The positive role of innovation-driven strategy is mainly realized through high-tech markets in China. Therefore, R&D investment should focus on high-tech industries or fields related to the national economic lifeline or strategic industries, such as environmental protection, microchips, and high-end instruments industries in China. 
  • 3.4K
  • 26 Apr 2022
Topic Review
Structural Components of the Neurovascular Unit
Formulated as a group effort of the stroke community, the transforming concept of the neurovascular unit (NVU) depicts the structural and functional relationship between brain cells and the vascular structure. Composed of both neural and vascular elements, the NVU forms the blood–brain barrier that regulates cerebral blood flow to meet the oxygen demand of the brain in normal physiology and maintain brain homeostasis. Conversely, the dysregulation and dysfunction of the NVU is an essential pathological feature that underlies neurological disorders spanning from chronic neurodegeneration to acute cerebrovascular events such as ischemic stroke and cerebral hemorrhage.
  • 3.4K
  • 29 Sep 2022
Topic Review
Beta-Catenin
Catenin beta-1, also known as β-catenin, is a protein that in humans is encoded by the CTNNB1 gene. β-catenin is a dual function protein, involved in regulation and coordination of cell–cell adhesion and gene transcription. In humans, the CTNNB1 protein is encoded by the CTNNB1 gene. In Drosophila, the homologous protein is called armadillo. β-catenin is a subunit of the cadherin protein complex and acts as an intracellular signal transducer in the Wnt signaling pathway. It is a member of the catenin protein family and homologous to γ-catenin, also known as plakoglobin. Beta-catenin is widely expressed in many tissues. In cardiac muscle, beta-catenin localizes to adherens junctions in intercalated disc structures, which are critical for electrical and mechanical coupling between adjacent cardiomyocytes. Mutations and overexpression of β-catenin are associated with many cancers, including hepatocellular carcinoma, colorectal carcinoma, lung cancer, malignant breast tumors, ovarian and endometrial cancer. Alterations in the localization and expression levels of beta-catenin have been associated with various forms of heart disease, including dilated cardiomyopathy. β-catenin is regulated and destroyed by the beta-catenin destruction complex, and in particular by the adenomatous polyposis coli (APC) protein, encoded by the tumour-suppressing APC gene. Therefore, genetic mutation of the APC gene is also strongly linked to cancers, and in particular colorectal cancer resulting from familial adenomatous polyposis (FAP).
  • 3.4K
  • 01 Dec 2022
Topic Review
Over Illumination
Over illumination is the presence of lighting intensity higher than that which is appropriate for a specific activity. Over illumination was commonly ignored between 1950 and 1995, especially in office and retail environments. Since then, however, the interior design community has begun to reconsider this practice. Over illumination encompasses two separate concerns: (1) Unnecessary electric lighting is expensive and energy-intensive. Lighting accounts for approximately 9% of residential electricity use (As of 2001) and about 40% of commercial electricity use. (2) Excessive levels of artificial light may adversely affect health. These detrimental effects may depend on the spectrum as well as the overall brightness level of light. Over illumination can be reduced by installing occupancy sensors, using natural sunlight whenever possible, turning off lights when leaving a room, or changing the type of lightbulb. Over illumination does not refer to snowblindness, where high exposure to ultraviolet light causes physical damage to the eye. Too little light, the opposite of over illumination, is associated with seasonal affective disorder.
  • 3.4K
  • 11 Oct 2022
Topic Review
Platelets
Recent advances in proteomic studies provided additional important information concerning the platelet biology and their response to several pathophysiological pathways. Platelets indeed are a heterogeneous small anucleate blood cell population with a central role both in physiological haemostasis and in pathological states, spanning from thrombosis to inflammation, and cancer.  Herein, a critical overview is provided on principal platelet proteomic studies focused on platelet biology from signalling to granules content, platelet proteome changes in several diseases, and the impact of drugs on platelet functions. Targeted quantification methods by means of mass spectrometry might be employed for more precise, robust and accurate quantification of selected proteins, which might be used as biomarkers for disease diagnosis, prognosis and therapy, and their strong clinical impact in the near future.
  • 3.4K
  • 07 Jul 2020
Topic Review
Crosstalk
Biological crosstalk refers to instances in which one or more components of one signal transduction pathway affects another. This can be achieved through a number of ways with the most common form being crosstalk between proteins of signaling cascades. In these signal transduction pathways, there are often shared components that can interact with either pathway. A more complex instance of crosstalk can be observed with transmembrane crosstalk between the extracellular matrix (ECM) and the cytoskeleton.
  • 3.4K
  • 08 Nov 2022
Topic Review
The 4R’s in Post-Exercise Recovery
A 4R’s approach to optimizing post-exercise recovery has been introduced: (i) Rehydration—a fundamental process that will depend on the athlete, environment and sports event; (ii) Refuel—the consumption of carbohydrates is not only important to replenish the glycogen reserves but also to contribute to the energy requirements for the immune system and tissue reparation. Several bioengineered carbohydrates were discussed but further research is needed; (iii) Repair—post-exercise ingestion of high-quality protein and creatine monohydrate benefit the tissue growth and repair; and (iv) Rest—pre-sleep nutrition has a restorative effect that facilitates the recovery of the musculoskeletal, endocrine, immune, and nervous systems. Nutritional consultancy based on the 4R’s is important for the wise stewardship of the hydration, feeding, and supplementation strategies to achieve a timely recovery. 
  • 3.4K
  • 25 Jan 2021
Topic Review
Monitoring Net Land Take in Europe
Land as an environmental resource has gained increasing importance in European policies. The target of “no net land take” by 2050, set by the 2011 Roadmap to a Resource Efficient Europe, is also reinforced by the Soil Strategy of the European Union for 2030. Net land take evaluates, for a given period, the difference between land take and developed land re-naturalization. Its reduction is only feasible by increasing the re-naturalization of developed land, an intervention undertaken in specific and rare circumstances. Accordingly, reusing or recycling developed land is the only intervention that substantially prevents land take. The following defines the three processes for which monitoring is necessary to evaluate the achievement of this target. Then, the legal framework of the European goal is presented, as well as the interventions that can contribute to its pursuit and the actions already taken by some countries and regions in Europe towards this end.
  • 3.4K
  • 13 Jul 2022
Topic Review
RNA Aptamers
RNA aptamers are becoming increasingly attractive due to their superior properties. 
  • 3.4K
  • 18 Jun 2021
Topic Review Peer Reviewed
The Infusion of Gamification in Promoting Chemical Engineering Laboratory Classes
Active learning strategies are increasingly implemented in chemical engineering education, yet challenges persist in stimulating student participation and motivation. The rigorous demands placed on students in this field, from complex practical requirements to extensive programming and computational skills, underscore the need for innovative educational tools. Gamification emerges as a pivotal instrument in this context, fostering active student engagement, enhancing practical application of knowledge, increasing motivation, and providing a more precise assessment of student comprehension. These educational games serve as a powerful adjunct to traditional teaching strategies, equipping students with necessary skills for their future careers in the field. These games include laboratory course games, process simulators, games used in foundational courses, and those centered around reaction kinetics. This entry primarily investigates the various games employed to bolster student learning during chemical engineering laboratory courses. A thorough analysis is conducted on the survey of existing games used specifically in chemical engineering labs. The gamut of games discussed includes escape games, along with Virtual Reality (VR) and Augmented Reality (AR) games, all aiming to enhance laboratory experiences in areas such as fluid mechanics, organic reactions, and process control. This entry concludes by examining the prospective trajectory of gamification in chemical engineering labs, offering insights into future potential and advancements in this innovative educational approach.
  • 3.4K
  • 05 Sep 2023
Topic Review
Epidemiology of Tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by Mycobacterium tuberculosis (MTB) bacteria. Tuberculosis generally affects the lungs, but can also affect other parts of the body. Most infections show no symptoms, in which case it is known as latent tuberculosis. About 10% of latent infections progress to active disease which, if left untreated, kills about half of those affected. Typical symptoms of active TB are a chronic cough with blood-containing mucus, fever, night sweats, and weight loss. It was historically called consumption due to the weight loss. Infection of other organs can cause a wide range of symptoms. Tuberculosis is spread from one person to the next through the air when people who have active TB in their lungs cough, spit, speak, or sneeze. People with latent TB do not spread the disease. Active infection occurs more often in people with HIV/AIDS and in those who smoke. Diagnosis of active TB is based on chest X-rays, as well as microscopic examination and culture of body fluids. Diagnosis of latent TB relies on the tuberculin skin test (TST) or blood tests. Prevention of TB involves screening those at high risk, early detection and treatment of cases, and vaccination with the bacillus Calmette-Guérin (BCG) vaccine. Those at high risk include household, workplace, and social contacts of people with active TB. Treatment requires the use of multiple antibiotics over a long period of time. Antibiotic resistance is a growing problem with increasing rates of multiple drug-resistant tuberculosis (MDR-TB). As of 2018, one quarter of the world's population was thought to have latent infection with TB. New infections occur in about 1% of the population each year. In 2018, there were more than 10 million cases of active TB, resulting in 1.5 million deaths and making it the number one cause of death from an infectious disease at that time. As of 2018, most TB cases occurred in the regions of South-East Asia (44%), Africa (24%) and the Western Pacific (18%), with more than 50% of cases being diagnosed in eight countries: India (27%), China (9%), Indonesia (8%), the Philippines (6%), Pakistan (6%), Nigeria (4%) and Bangladesh (4%). The number of new cases each year has decreased since 2000. About 80% of people in many Asian and African countries test positive while 5–10% of people in the United States population test positive by the tuberculin test. Tuberculosis has been present in humans since ancient times. 
  • 3.4K
  • 09 Oct 2022
Topic Review
Ordnance QF 75 Mm
The Ordnance QF 75 mm, abbreviated to OQF 75 mm, was a British tank-gun of the Second World War. It was obtained by boring out the Ordnance QF 6 pounder ("6 pdr") 57-mm anti-tank gun to 75-mm, to give better performance against infantry targets in a similar fashion to the 75mm M3 gun fitted to the American Sherman tank. The QF came from "quick-firing", referring to the use of ammunition with the shell and propellant in a single cartridge. The gun was also sometimes known as ROQF from Royal Ordnance (the manufacturer) Quick-Firing.
  • 3.4K
  • 02 Nov 2022
Topic Review
Environmental Aspects of the Electric Car
Electric cars (or electric vehicles, EVs) have different environmental impacts compared to conventional internal combustion engine vehicles (ICEVs). While aspects of their production can induce similar, less or alternative environmental impacts, some models produce little or no tailpipe emissions, and some have the potential to reduce dependence on petroleum and greenhouse gas emissions, depending on the source of electricity used to charge them, and health effects from air pollution. Electric motors are significantly more efficient than internal combustion engines and thus, even accounting for typical power plan efficiencies and distribution losses, less energy is required to operate an EV. Producing batteries for electric cars requires additional resources and energy, so they may have a larger environmental footprint from the production phase. EVs also generate different impacts in their operation and maintenance. EVs are typically heavier and could produce more tire, brake, and road dust, but their regenerative braking could reduce brake particulate pollution. EVs are mechanically simpler, which reduces the use and disposal of engine oil.
  • 3.4K
  • 30 Nov 2022
Topic Review
Cutaneous Manifestations in Pancreatic Diseases
Pancreatic pathology, comprising acute and chronic pancreatitis, autoimmune pancreatitis and pancreatic neoplasms, primarily presents with gastrointestinal symptoms and signs; however, it is well recognized that it can also associate a wide range of extra-digestive features. Among these systemic manifestations, cutaneous involvement plays an important role both as a diagnostic clue for the pancreatic disease itself and serving as a prognostic factor for the severity of the condition.
  • 3.4K
  • 27 Oct 2020
Topic Review
2-Phenylethanol
2-Phenylethanol (2-PE), also known as 2-phenethyl alcohol, is a higher aromatic alcohol characterized by one of the most popular and desired fragrances, which is the rosy scent.
  • 3.4K
  • 13 Jan 2022
Biography
Michael Green (Physicist)
Michael Boris Green FRS[1] (born 22 May 1946) is a British physicist and one of the pioneers of string theory. Currently a Professor of Theoretical Physics in the School of Physics and Astronomy at Queen Mary University of London, and emeritus professor in the Department of Applied Mathematics and Theoretical Physics and a Fellow in Clare Hall, Cambridge in England, he was Lucasian Professor of
  • 3.4K
  • 04 Jan 2023
Topic Review
Bacteroidetes
The phylum "Bacteroidetes" is composed of three large classes of Gram-negative, nonsporeforming, anaerobic or aerobic, and rod-shaped bacteria that are widely distributed in the environment, including in soil, sediments, and sea water, as well as in the guts and on the skin of animals. Although some Bacteroides spp. can be opportunistic pathogens, many "Bacteroidetes" are symbiotic species highly adjusted to the gastrointestinal tract. Bacteroides are highly abundant in intestines, reaching up to 1011 cells g−1 of intestinal material. They perform metabolic conversions that are essential for the host, such as degradation of proteins or complex sugar polymers. "Bacteroidetes" colonize the gastrointestinal tract already in infants, as non-digestible oligosaccharides in mother milk support the growth of both Bacteroides and Bifidobacterium spp. Bacteroides spp. are selectively recognized by the immune system of the host through specific interactions.
  • 3.4K
  • 21 Jul 2025
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