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Topic Review
Coumarin-Based Profluorescent and Fluorescent Substrates
Activities of xenobiotic-metabolizing enzymes have been measured with various in vitro and in vivo methods, such as spectrophotometric, fluorometric, mass spectrometric and radioactivity-based techniques. In fluorescence-based assays, the reaction produces a fluorescent product from a nonfluorescent substrate or vice versa. We describe here historical highlights and current use of (pro)fluorescent coumarin derivatives in evaluating activities of the major types of xenobiotic-metabolizing enzyme systems. Traditionally coumarin substrates have been used to measure oxidative activities of cytochrome P450 (CYP) enzymes. For this purpose, profluorescent coumarins are very sensitive, but generally lack selectivity for individual CYP forms. The entry describes several new coumarin-based substrates for measuring activities of CYP and conjugating enzymes with improved selectivity.
  • 3.1K
  • 14 Jul 2020
Topic Review
Ring
Ring LLC is a home security and smart home company owned by Amazon. Ring manufactures home security products that incorporate outdoor surveillance cameras, including the Ring Video Doorbell smart doorbell, and hosts an app, Neighbors, for online social sharing of captured footage among users. Ring also provides video footage from its cameras and data from its Neighbors app to law enforcement agencies on request. Its police partnerships have been criticized by civil rights advocacy groups as building an invasive private surveillance network.
  • 3.1K
  • 18 Oct 2022
Topic Review
Envy
Envy (from Latin invidia) is an emotion which occurs when a person lacks another's superior quality, achievement, or possession and either desires it or wishes that the other lacked it. Aristotle defined envy as pain at the sight of another's good fortune, stirred by "those who have what we ought to have". Bertrand Russell said that envy was one of the most potent causes of unhappiness. Not only is the envious person rendered unhappy by their envy, Russell argued, but that person may also wish to inflict misfortune on others to reduce their status.
  • 3.1K
  • 14 Nov 2022
Topic Review
Bus Scheduling with Evolutionary Optimization
In public transport operations, vehicles tend to bunch together due to the instability of passenger demand and traffic conditions. Fluctuation of the expected waiting times of passengers at bus stops due to bus bunching is perceived as service unreliability and degrades the overall quality of service. For assessing the performance of high-frequency bus services, transportation authorities monitor the daily operations via Transit Management Systems (TMS) that collect vehicle positioning information in near real-time. This work explores the potential of using Automated Vehicle Location (AVL) data from the running vehicles for generating bus schedules that improve the service reliability and conform to various regulatory constraints. The computer-aided generation of optimal bus schedules is a tedious task due to the nonlinear and multi-variable nature of the bus scheduling problem. For this reason, this work develops a two-level approach where (i) the regulatory constraints are satisfied and (ii) the waiting times of passengers are optimized with the introduction of an evolutionary algorithm. This work also discusses the experimental results from the implementation of such an approach in a bi-directional bus line operated by a major bus operator in northern Europe.
  • 3.1K
  • 29 Oct 2020
Topic Review Peer Reviewed
Understanding the Gut-Heart Axis in Roemheld Syndrome: Mechanisms and Clinical Insights
This entry reviews the health condition known as Roemheld syndrome, or gastrocardiac syndrome in modern medicine. A pathology of gastrointestinal origin, the syndrome relies on a gut–brain–heart triad, interconnected by the vagus nerve. Pressure from the intestines pushes the stomach into the diaphragm and activates the vagus nerve, which affects the heart rate and gives the perception of cardiac issues. This distressing sensation, which usually comes after meals or with other digestive problems, causes anxiety or panic. Although events not arising from anatomic abnormalities are relatively harmless, hypersensitivity to these uncomfortable sensations may precipitate psychiatric problems (anxiety or depression) that cause repeated gastrocardiac events through sympathetic activation and the disruption of peristalsis. Treatment is usually symptomatic and may include diet, lifestyle changes, probiotics, or prescriptions that increase gut motility, but this specific set of reproducible symptoms may also be caused by hiatal hernia or side effects from medication/surgery and treated with respect to those mechanical causes. This review highlights details from the most current knowledge of the condition and offers suggestions for clinical management based on the literature.
  • 3.1K
  • 22 Nov 2024
Topic Review
Volumetric Muscle Loss
Volumetric muscle loss (VML) is the massive wasting of skeletal muscle tissue due to traumatic events or surgical ablation. This pathological condition exceeds the physiological healing process carried out by the muscle itself, which owns remarkable capacity to restore damages but only when limited in dimensions. Upon VML occurring, the affected area is severely compromised, heavily influencing the affected person’s quality of life. Overall, this condition is often associated with chronic disability, which makes the return to duty of highly specialized professional figures (e.g., military personnel or athletes) almost impossible. The actual treatment for VML is based on surgical conservative treatment followed by physical exercise; nevertheless, the results, in terms of either lost mass and/or functionality recovery, are still poor. On the other hand, the efforts of the scientific community are focusing on reconstructive therapy aiming at muscular tissue void volume replenishment by exploiting biomimetic matrix or artificial tissue implantation. Reconstructing strategies represent a valid option to build new muscular tissue not only to recover damaged muscles, but also to better socket prosthesis in terms of anchorage surfaces and reinnervation substrates for reconstructed mass. 
  • 3.1K
  • 26 May 2021
Topic Review
List of Years in Home Video
This page indexes the individual year in home video pages. Some years are annotated with a significant event as a reference point.
  • 3.1K
  • 21 Oct 2022
Topic Review
Neonatal Early-Onset Sepsis
Neonatal early-onset sepsis (EOS) is defined as an invasive infection that occurs in the first 72 h of life. The incidence of EOS varies from 0.5–2 per 1000 live births in developed countries, up to 9.8 per 1000 live births in low resource settings, generating a high mortality rate, especially in extremely low birth weight neonates. Clinical signs are nonspecific, leading to a late diagnosis and high mortality. Currently, there are several markers used for sepsis evaluation, such as hematological indices, acute phase reactants, cytokines, which by themselves do not show acceptable sensitivity and specificity for the diagnosis of EOS in neonates. Newer and more selective markers have surfaced recently, such as presepsin and endocan, but they are currently only in the experimental research stages.
  • 3.1K
  • 28 Sep 2021
Topic Review
Chromothripsis
Chromothripsis has been defined as complex patterns of alternating genes copy number changes (normal, gain or loss) along the length of a chromosome or chromosome segment (International System for Human Cytogenomic Nomenclature 2020). The phenomenon of chromothripsis was discovered in 2011 and changed the concept of genome variability, mechanisms of oncogenic transformation, and hereditary diseases.
  • 3.1K
  • 27 May 2021
Topic Review
CO2 Storage in Shale Reservoirs
As a new “sink” of CO2 permanent storage, the depleted shale reservoir is very promising compared to the deep saline aquifer. To provide a greater understanding of the benefits of CO2 storage in a shale reservoir, a comparative study is conducted by establishing the full-mechanism model, including the hydrodynamic trapping, adsorption trapping, residual trapping, solubility trapping as well as the mineral trapping corresponding to the typical shale and deep saline aquifer parameters from the Ordos basin in China. The results show that CO2 storage in the depleted shale reservoir has merits in storage safety by trapping more CO2 in stable immobile phase due to adsorption and having gentler and ephemeral pressure perturbation responding to CO2 injection. The effect of various CO2 injection schemes, namely the high-speed continuous injection, low-speed continuous injection, huff-n-puff injection and water alternative injection, on the phase transformation of CO2 in a shale reservoir and CO2-injection-induced perturbations in formation pressure are also examined. With the aim of increasing the fraction of immobile CO2 while maintaining a safe pressure-perturbation, it is shown that an intermittent injection procedure with multiple slugs of huff-n-puff injection can be employed and within the allowable range of pressure increase, and the CO2 injection rate can be maximized to increase the CO2 storage capacity and security in shale reservoir.
  • 3.1K
  • 11 Jan 2021
Topic Review
Beneficial Biological Effects of Helichrysum italicum
Helichrysum italicum (family Asteraceae), due to its various beneficial biological effects, represents an important plant in the traditional medicine of Mediterranean countries. There is a renewed interest in this medicinal plant, especially in investigations involving the isolation and identification of its bioactive compounds from extracts and essential oils, as well as in experimental validation of their pharmacological activities. The research is focused on the beneficial biological effects of Helichrysum italicum extracts, essential oils, and their major bioactive polyphenolic compounds, ranging from antioxidative, anti-inflammatory, and anticarcinogenic activities to their antiviral, antimicrobial, insecticidal, and antiparasitic effects.
  • 3.1K
  • 08 Mar 2023
Topic Review
Organic Fouling
Organic fouling in the forward osmosis process is complex and influenced by different parameters in the forward osmosis such as type of feed and draw solution, operating conditions and type of membrane. In this article, we reviewed organic fouling in the forward osmosis focussing on wastewater treatment applications. Model organic foulants used in the forward osmosis literature were highlighted, followed by the characteristics of organic foulants when real wastewater are used as feed solutions. The present study evaluated various physical and chemical cleaning protocols for organic fouled membrane and the efficiency of cleaning methods for the removal of organic fouling in the forward osmosis process. The study made recommendations on future cleaning technologies such as Ultraviolet and Ultrasound. Generally, a combination of physical and chemical cleaning is the best for restoring the water flux in the FO process.
  • 3.1K
  • 27 Oct 2020
Topic Review
Nepalese Army On Buffer Zone
Recent years have seen various advancements in exploration and the progress of arm forces throughout the world. Nepal is in the buffer zone. The people of Nepal sometimes face unhealthy pressure from India and sometimes from China. Indeed, the founding father of modern Nepal, King Prithvi Narayan Shah's dictum, "Nepal as a yam between two boulders". The people of the Northern part of Nepal are somehow similar cultures with Tibet(China) and they need to adjust with the people of Tibet. Similarly, east, west, and south parts of Nepal has somehow similar culture with India and they need to adjust with the people of India. This article reviews top-cited recent literature and made a compact analytical review on the buffer zone which can be useful for new researchers.
  • 3.1K
  • 05 Jan 2021
Topic Review
Lingua Geographica
Geographic tongue, also known by several other terms,[note 1] is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.
  • 3.1K
  • 26 Oct 2022
Topic Review
Regulationary Factors of the Peroxisomal β-Oxidation
Beta-oxidation(β-oxidation) is an important metabolic process involving multiple steps by which fatty acid molecules are broken down to produce energy. The very long-chain fatty acids (VLCFAs), a type of fatty acid (FA), are usually highly toxic when free in vivo, and their oxidative metabolism depends on the peroxisomal β-oxidation. Although peroxisomal β-Oxidation attracts less research than mitochondria, the importance of the peroxisomal β-oxidation molecular mechanism can still be spotted from some mechanisms involved in upstream regulation.
  • 3.1K
  • 07 Jul 2022
Topic Review
Mars (Planet)
Mars is the fourth planet from the Sun in our solar system and is named after Mars, the Roman god of war. Mars is also known as the "Red Planet" due to its reddish appearance when seen from Earth. The prefix areo-, from the Greek god of war, Ares, refers to Mars in the same way geo- refers to Earth. Until the first flyby of Mars by Mariner 4 in 1965, it was thought that Mars had channels of liquid water. Observations later showed that these channels do not exist. Still, of all the planets in our solar system other than Earth, Mars is the most likely to harbor liquid water, and perhaps life. Its rotational period and seasonal cycles are also similar to those of the Earth. It has the highest mountain in the solar system, Olympus Mons, the largest canyon in the solar system, Valles Marineris, and polar ice caps. Mars has two moons, Phobos and Deimos, which are small and oddly-shaped. These may be captured asteroids similar to 5261 Eureka, a Mars trojan asteroid. Mars can be seen from Earth by the naked eye. Its apparent magnitude reaches -2.9, a brightness surpassed only by Venus, the Moon, and the Sun. For much of the year, Jupiter may appear brighter to the naked eye than Mars. Mars is currently host to four orbiting spacecraft, more than any planet other than Earth. It is also home to the two Mars Exploration Rovers, Spirit and Opportunity.
  • 3.1K
  • 21 Nov 2022
Biography
Michel de Montaigne
Michel Eyquem de Montaigne (/mɒnˈteɪn/ mon-TAYN;[1] French: [miʃɛl ekɛm də mɔ̃tɛɲ]; 28 February 1533 – 13 September 1592[2]), also known as Lord of Montaigne, was one of the most significant philosophers of the French Renaissance. He is known for popularizing the essay as a literary genre. His work is noted for its merging of casual anecdotes[3] and autobiography with intellectual
  • 3.1K
  • 05 Dec 2022
Topic Review
Curcumin in Neuropsychiatric Disorders
Curcumin is a polyphenol extracted from the rhizome of turmeric plant. Beyond its common use as a culinary spice in Eastern Asia, curcumin has been proposed as a therapeutic compound due to its antioxidant, anti-inflammatory and neuroprotective properties. Thus, its efficacy has been evaluated in various inflammatory-based psychiatric disorders, such as schizophrenia, depression or autism. 
  • 3.1K
  • 27 Jul 2022
Topic Review
COVID-19 Vaccine
A COVID‑19 vaccine is a hypothetical vaccine in development against coronavirus disease 2019 (COVID‑19). Although no candidate has completed clinical trials to prove its safety and efficacy, there are multiple efforts in progress to develop one. As of July 2020, there are 24 vaccine candidates planned or undergoing clinical trials, with two beginning Phase III and seven in Phase I-II. Previous attempts to develop a vaccine against the coronavirus diseases SARS and MERS established considerable knowledge about the structure and function of coronaviruses – which accelerated rapid development during early 2020 of varied technology platforms for a COVID‑19 vaccine – but all the previous coronavirus vaccine candidates failed in early-stage clinical trials, with none being advanced to licensing. The Coalition for Epidemic Preparedness Innovations (CEPI) – which is organizing a US$2 billion worldwide fund for rapid investment and development of vaccine candidates – indicated in April that a vaccine may be available under emergency use protocols in less than 12 months or by early 2021. On 4 May 2020, the WHO organized a telethon which received US$8.1 billion in pledges from forty countries to support rapid development of vaccines to prevent COVID‑19 infections. At the same time, the WHO also announced deployment of an international "Solidarity trial" for simultaneous evaluation of several vaccine candidates reaching Phase II-III clinical trials.
  • 3.1K
  • 09 Nov 2022
Topic Review
Lake Taupo
Lake Taupo, often spelled Taupō, is a lake in the North Island of New Zealand. It is in the caldera of the Taupo Volcano. The lake is the namesake of the town of Taupō, which sits on a bay in the lake's north-eastern shore. With a surface area of 616 square kilometres (238 sq mi), it is the largest lake by surface area in New Zealand, and the second largest freshwater lake by surface area in geopolitical Oceania after Lake Murray in Papua New Guinea. Motutaiko Island lies in the south east area of the lake. Lake Taupo has a perimeter of approximately 193 kilometres and a maximum depth of 186 metres. It is drained by the Waikato River (New Zealand's longest river), and its main tributaries are the Waitahanui River, the Tongariro River, and the Tauranga Taupo River. It is a noted trout fishery with stocks of introduced brown and rainbow trout. The level of the lake is controlled by Mercury Energy, the owner of the eight hydroelectric dams on the Waikato River downstream of Lake Taupo, using gates built in 1940–41. The gates are used to reduce flooding, conserve water and ensure a minimum flow of 50 m3/s (1,800 cu ft/s) in the Waikato River. The resource consent allows the level of the lake to be varied between 355.85 and 357.25 metres (1,167.5 and 1,172.1 ft) above sea level.
  • 3.1K
  • 08 Nov 2022
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