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Topic Review
Bhikkhu
A bhikkhu (Pali: भिक्खु Sanskrit: भिक्षु , bhikṣu) is an ordained male monastic ("monk") in Buddhism. Male and female monastics ("nun", bhikkhunī, Sanskrit bhikṣuṇī) are members of the Buddhist community. The lives of all Buddhist monastics are governed by a set of rules called the prātimokṣa or pātimokkha. Their lifestyles are shaped to support their spiritual practice: to live a simple and meditative life and attain nirvana. A person under the age of 20 cannot be ordained as a bhikkhu or bhikkhuni but can be ordained as a śrāmaṇera or śrāmaṇērī.
  • 3.4K
  • 31 Oct 2022
Topic Review
α-Lactalbumin
α-Lactalbumin (α-LA) is a small (Mr 14,200), acidic (pI 4-5), Ca2+-binding protein. α-LA is a regulatory component of lactose synthase enzyme system. α-LA is very important in infant nutrition since it constitutes a large part of the whey and total protein in human milk. The protein possesses a single strong Ca2+-binding site, which can also bind Mg2+, Mn2+, Na+, K+, and some other metal cations. It contains several distinct Zn2+-binding sites. Physical properties of α-LA strongly depend on the occupation of its metal binding sites by metal ions. In the absence of bound metal ions α-LA is in the molten globule-like state. The binding of metal ions, and especially of Ca2+, increases stability of α-LA against action of heat, various denaturing agents, and proteases, while the binding of Zn2+ to the Ca2+-loaded protein decreases its stability and causes its aggregation. The thermal unfolding of apo-α-LA takes place in the temperature region from 10 to 30 °C. The binding of Ca2+ under the conditions of low ionic strength shifts the thermal transition to higher temperatures by more than 40 °C. The binding of Mg2+, Na+, and K+ increases protein stability as well. The stronger an ion binds to the protein, the more pronounced the thermal transition shift. All four classes of surfactants (anionic, cationic, non-ionic, and zwitterionic) denature α-LA and the denaturation involves at least one intermediate. The position of any denaturation transition in α-LA (half-transition temperature, half-transition pressure, half-transition denaturant concentration) depends upon metal ion concentration in solution (especially if this metal ion is Ca2+). Therefore, values of denaturation temperature or urea or guanidine hydrochloride denaturing concentration are relatively meaningless for α-LA without specifying the metal ion content(s) and their solution concentration(s). At a neutral or slightly acidic pH at a physiological temperature, α-LA can associate with membranes. The conformations of the membrane-bound protein range from native-like to molten globule-like states. At a low pH, α-LA penetrates the interior of the negatively charged membranes and exhibits a molten globule conformation. Depending on external conditions, α-LA can form amyloid fibrils, amorphous aggregates, nanoparticles, and nanotubes. At pH 2, α-LA in the classical molten globule conformation can form amyloid fibrils. Some of these aggregated states of α-LA (nanoparticles, nanotubes) can be used in practical applications such as drug delivery to tissues and organs. The structure and self-assembly behavior of α-LA are governed by a subtle balance between hydrophobic and polar interactions and this balance can be finely tuned through the addition of selected substances. Small size nanoparticles of α-LA (100 to 200 nm) can be obtained with the use of various desolvating agents. Partially hydrolyzed α-LA can form nanotubes. α-LA and some of its fragments possess bactericidal and antiviral activities. Complexes of partially unfolded α-LA with oleic acid showed significant cytotoxicity to various tumor and bacterial cells. α-LA in such complexes plays a role of a delivery carrier of cytotoxic fatty acid molecules into tumor cells across the cell membrane. Cytotoxic protein–oleic acid complexes possess a common core-shell structure, where an oily core is made of a micellar oleic acid, whereas a proteinaceous shell, which stabilizes the oleic acid micelle, is formed from the flexible, partially unfolded proteins. These complexes called liprotides (lipids and partially denatured proteins), which are potential novel anti-tumorous drugs, can be considered as molten globular containers filled with the toxic oil.
  • 3.4K
  • 31 Aug 2020
Topic Review
Nrf2 Signaling Pathway
Nrf2 and its principal negative regulator, the E3 ligase adaptor Kelch-like ECH- associated protein 1 (Keap1), play a central role in the maintenance of intracellular redox homeostasis and regulation of inflammation. Interestingly, Nrf2 is proven to contribute to the regulation of the heme oxygenase-1 (HO-1) axis, which is a potent anti-inflammatory target. Recent studies showed a connection between the Nrf2/antioxidant response element (ARE) system and the expression of inflammatory mediators, NF-κB pathway and macrophage metabolism. Thus, Nrf2 is part of a multilayered network that plays a key role in redox homeostasis as well as in inflammation. This suggests a new strategy for designing chemical agents as modulators of Nrf2 dependent pathways to target the immune response.
  • 3.4K
  • 15 Dec 2020
Topic Review
Closed Ecological Life Support Systems
Closed ecological life support systems (CELSS) requires agricultural production for food, CO2removal, O2generation (human respiratory quotient ofCO2/[O2= 0.84–0.87 depending on the percentage formation of carbohydrate, fat and protein in the food consumed) and water recycling with bioreactors for recycling waste. Plants consume CO2and H2O for photosynthesis under the action of sufficient PAR to produce carbohydrate food, regenerate oxygen and filter water through evapotranspiration. There have been several bioregenerative life support system programmes including Biosphere 2 (US), CELSS (NASA), Bios-3 (Roscosmos) and its predecessors and MELiSSA (ESA).
  • 3.4K
  • 13 Aug 2021
Topic Review Peer Reviewed
The Role of GNSS-RTN in Transportation Applications
The Global Navigation Satellite System—Real-Time Network (GNSS-RTN) is a satellite-based positioning system using a network of ground receivers (also called continuously operating reference stations (CORSs)) and a central processing center that provides highly accurate location services to the users in real-time over a broader geographic region. Such systems can provide geospatial location data with centimeter-level accuracy anywhere within the network. Geospatial location services are not only used in measuring ground distances and mapping topography; they have also become vital in many other fields such as aerospace, aviation, natural disaster management, and agriculture, to name but a few. The innovative and multi-disciplinary applications of geospatial data drive technological advancement towards precise and accurate location services available in real-time. Although GNSS-RTN technology is currently utilized in a few industries such as precision farming, construction industry, and land surveying, the implications of precise real-time location services would be far-reaching and more critical to many advanced transportation applications. The GNSS-RTN technology is promising in meeting the needs of automation in most advanced transportation applications. This article presents an overview of the GNSS-RTN technology, its current applications in transportation-related fields, and a perspective on the future use of this technology in advanced transportation applications. 
  • 3.4K
  • 05 Jul 2022
Topic Review
Street Canyon
A street canyon (also known as an urban canyon) is a place where the street is flanked by buildings on both sides creating a canyon-like environment. Classic examples of these human-built canyons are made when streets separate dense blocks of structures, especially skyscrapers. These include the Magnificent Mile in Chicago, Toronto's Financial District, the Canyon of Heroes in Manhattan and Hong Kong's Kowloon and Central districts. Urban canyons affect various local conditions, including temperature, wind, air quality, and radio reception, including satellite navigation signals.
  • 3.4K
  • 26 Oct 2022
Topic Review
Marsupial Lion
The marsupial lion (Thylacoleo carnifex) is an extinct species of carnivorous marsupial mammal that lived in Australia from the early to the late Pleistocene (1,600,000–46,000 years ago). Despite its name, it is not closely related to the lion, but is a member of the order Diprotodontia, one of the taxonomic groups of Australian marsupials.
  • 3.4K
  • 20 Oct 2022
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
Minimum Wage
A minimum wage is the lowest remuneration that employers can legally pay their employees—the price floor below which employees may not sell their labor. Most countries had introduced minimum wage legislation by the end of the 20th century. Because minimum wages increase the cost of labor, companies often try to avoid minimum wage laws by using gig workers, by moving labor to locations with lower or nonexistent minimum wages, or by automating job functions. The movement for minimum wages was first motivated as a way to stop the exploitation of workers in sweatshops, by employers who were thought to have unfair bargaining power over them. Over time, minimum wages came to be seen as a way to help lower-income families. Modern national laws enforcing compulsory union membership which prescribed minimum wages for their members were first passed in New Zealand and Australia in the 1890s. Although minimum wage laws are now in effect in many jurisdictions, differences of opinion exist about the benefits and drawbacks of a minimum wage. Supply and demand models suggest that there may be employment losses from minimum wages. However, minimum wages can increase the efficiency of the labor market in monopsony scenarios, where individual employers have a degree of wage-setting power over the market as a whole. Supporters of the minimum wage say it increases the standard of living of workers, reduces poverty, reduces inequality, and boosts morale. In contrast, opponents of the minimum wage say it increases poverty and unemployment because some low-wage workers "will be unable to find work...[and] will be pushed into the ranks of the unemployed".
  • 3.4K
  • 30 Nov 2022
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
Topic Review
Microsoft OneDrive
Microsoft OneDrive (formerly SkyDrive) is a file hosting service and synchronization service operated by Microsoft as part of its web version of Office. First launched in August 2007, OneDrive allows users to store files and personal data like Windows settings or BitLocker recovery keys in the cloud, share files, and sync files across Android, Windows Phone, and iOS mobile devices, Windows and macOS computers, and the Xbox 360, Xbox One, and Xbox Series X and S consoles. Users can upload Microsoft Office documents to OneDrive. OneDrive offers 5 GB of storage space free of charge, with 100 GB, 1 TB, and 6 TB storage options available either separately or with Office 365 subscriptions.
  • 3.4K
  • 01 Nov 2022
Topic Review
Cancer (Constellation)
Cancer, recognized as one of the twelve zodiac constellations, is situated in the northern celestial hemisphere. Named after the Latin word for crab, Cancer is associated with the Greek myth of the crab sent by Hera to distract Hercules during his battle with the Hydra.
  • 3.4K
  • 29 Feb 2024
Topic Review
Jáchymov
Jáchymov (Czech pronunciation: [ˈjaːxɪmof]); German: Sankt Joachimsthal or Joachimsthal) is a spa town in Karlovy Vary District in the Karlovy Vary Region of the Czech Republic. It has about 2,300 inhabitants. The historical core of the town from the 16th century is well preserved and protected by law as urban monument zone. It is a comprehensive set of Gothic–Renaissance patrician houses. Jáchymov has a long mining tradition, thanks to which it used to be the second most populous town in the Kingdom of Bohemia in 1534. At first silver was mined here. The silver Joachimsthaler coins minted here since the 16th century gave their name to the Thaler and the dollar. After the Wieliczka Salt Mine ceased industrial exploitation in 2007, the Svornost mine (1525) became the oldest mine still in use in Europe. It is also the first and for a long time the only mine in the world, where radium was mined. The mining cultural landscape of Jáchymov is a UNESCO World Heritage Site as a part of the Ore Mountain Mining Region.
  • 3.4K
  • 04 Nov 2022
Topic Review
Climate Change Maladaptation
Maladaptation is caused by adaptation that fails to reduce vulnerability or inadvertently increases it. Maladaptation can be defined as: ''maladaptation occurs when short-term strategies increase vulnerability in the long term'' or ''action taken ostensibly to avoid or reduce vulnerability to climate change that impacts adversely on, or increase the vulnerability of other systems, sectors, or social groups.''
  • 3.4K
  • 29 Mar 2021
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
Physiological and Anatomical Changes of Pregnancy
During pregnancy, a woman’s body undergoes various changes, both physiological and anatomical, necessary to meet the increased metabolic needs in order to support the growing fetus, for its harmonious development and also to prepare the body for birth. It has been observed that the first changes appear in the first trimester of pregnancy and intensify once the final term is reached and return to normal a few weeks after birth. The physiological changes produced by pregnancy are generally well tolerated by healthy women, but certain changes are still likely to aggravate different pathologies or give rise to a variety of disorders, especially musculoskeletal, which is the most common in pregnancy. A woman’s body undergoes major changes during pregnancy in all organs to support both the mother and the fetus.
  • 3.4K
  • 15 Nov 2023
Topic Review
Internet of Everything (IoE) Taxonomies
The paradigm of the Internet of everything (IoE) is advancing toward enriching people’s lives by adding value to the Internet of things (IoT), with connections among people, processes, data, and things. This paper provides a survey of the literature on IoE research, highlighting concerns in terms of intelligence services and knowledge creation. The significant contributions of this study are as follows: (1) a systematic literature review of IoE taxonomies (including IoT); (2) development of a taxonomy to guide the identification of critical knowledge in IoE applications, an in-depth classification of IoE enablers (sensors and actuators); (3) validation of the defined taxonomy with 50 IoE applications; and (4) identification of issues and challenges in existing IoE applications (using the defined taxonomy) with regard to insights about knowledge processes.
  • 3.4K
  • 27 Jan 2021
Topic Review
Dihydropyrrolo[1,2-a]Pyrazinones
Dihydropyrrolo[1,2-a]pyrazinone rings are a class of heterocycles present in a wide range of bioactive natural products and analogues thereof. As a direct result of their bioactivity, the synthesis of this privileged class of compounds has been extensively studied. This review provides an overview of these synthetic pathways.
  • 3.4K
  • 09 Jun 2021
Topic Review
Flow (Psychology)
In positive psychology, a flow state, also known colloquially as being in the zone, is the mental state in which a person performing some activity is fully immersed in a feeling of energized focus, full involvement, and enjoyment in the process of the activity. In essence, flow is characterized by the complete absorption in what one does, and a resulting transformation in one's sense of time. Named by the psychologist Mihály Csíkszentmihályi in 1975, the concept has been widely referred to across a variety of fields (and is particularly well recognized in occupational therapy), though the concept has been claimed to have existed for thousands of years under other names. The flow state shares many characteristics with hyperfocus. However, hyperfocus is not always described in a positive light. Some examples include spending "too much" time playing video games or becoming pleasurably absorbed by one aspect of an assignment or task to the detriment of the overall assignment. In some cases, hyperfocus can "capture" a person, perhaps causing them to appear unfocused or to start several projects, but complete few. Hyperfocus is often mentioned "in the context of autism, schizophrenia, and attention deficit hyperactivity disorder- conditions that have consequences on attentional abilities."
  • 3.4K
  • 30 Sep 2022
Topic Review
Synthesis of Thienothiophenes
Thienothiophenes (TT), formed by two annulated thiophene rings, represent fully the planar system, whose embedding into a molecular architecture can significantly improve/alter the fundamental properties of organic, π-conjugated materials. 
  • 3.4K
  • 21 Nov 2022
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