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Topic Review
Penal Military Unit
Penal military units, including penal battalions, penal companies, etc., are military formations consisting of convicts mobilized for military service. Such formations may contain soldiers convicted of offenses under military law, persons enrolled in the unit after being convicted in civilian courts or some combination of the two. Service in such units is typically considered a form of punishment or discipline in lieu of imprisonment or capital punishment.
  • 5.3K
  • 02 Nov 2022
Topic Review
Metal–Organic Framework-Based Membranes for Gas Separation
Metal–organic frameworks (MOFs) represent the largest class of materials among crystalline porous materials ever developed, and have attracted attention as core materials for separation technology. Their extremely uniform pore aperture and nearly unlimited structural and chemical characteristics have attracted great interest and promise for applying MOFs to adsorptive and membrane-based separations. 
  • 5.3K
  • 28 Feb 2024
Topic Review
Energy Use in Greenhouses in the EU
High energy systems, which are more dominant in northern Europe, are generally heavily climate controlled and energy use is dominated by heating and cooling processes, while low energy systems, which are dominant in southern Europe, show a mixture of energy uses including heating, cooling, irrigation, lighting, fertilisers, and pesticides.
  • 5.3K
  • 27 May 2022
Topic Review
Non-Medical Applications of Chitosan Nanocomposite Coatings
Millions of tons of crustaceans are produced every year and consumed as protein-rich seafood but the shells and other non-edible parts constituting about half the body mass are wasted. The crustacean shells are a prominent source of polysaccharide (chitin) and protein. Chitosan, a de-acetylated form of chitin obtained from the crustacean waste are used for a variety of medical applications. In recent times, it has also found use in food and paint industries including marine antifouling coatings, due to its characteristic properties, like solubility in weak acids, film-forming ability, pH-sensitivity, antifouling properties, biodegradability, and biocompatibility. Chitosan composite coatings in food, paint and water treatment solutions have been developed. In food industries, chitosan-based composite films and coatings are applied for prolonging the post-harvest life of fruits and vegetables, while anti-corrosion and self-healing properties are mainly explored for antifouling applications in paints and metal ion chelation and antifouling properties are useful for water treatment.
  • 5.3K
  • 29 Oct 2020
Topic Review
Acid Rain
Acid rain has an acidity that is higher than that of normal rainwater. Normal rainwater is not neutral (which would be pH 7) but slightly acidic (it has a pH < 5.5), because some of the carbon dioxide CO2 dissolved in the water is present as carbonic acid H2CO3. In acid rain, chemicals from pollution and natural causes such as volcanic eruptions and emissions from vegetation increase the acidity of the water to as low as pH 4.4 to 4 (as measured in the 1990s in various places). Such acidic rainwater is dangerous for people, vegetation, water bodies including the oceans and its inhabitants, buildings and soil. Since the pH scale is logarithmic, a change from 5.5 to 4.5 means a tenfold increase in acidity. The three main pollutants that cause acid rain are the nitric oxides NO and NO2 (summarized as NOx) and sulfur dioxide SO2. These substances react with water to nitric acid HNO3 and sulfuric acid H2SO4. In the 1980s, in nearly all of Northern Europe and in the Northern United States, suddenly and unexpectedly, whole forests began to die (this effect got to be known as forest dieback). German forests especially experienced severe damage: from 8% in 1982 it increased to 50% in 1984, and stayed as such till 1987. The damage occurred amongst various tree species. Researchers established connections of this damage to acid rain. The mandatory installment of sulfur filters in coal power plants and of catalytic converters in cars in various industrialized countries reduced air pollution with the chemicals related to the formation of acid rain, and, although the forests are still not in perfect shape (about 20% are heavily impaired) a complete death was prevented.
  • 5.3K
  • 15 Nov 2022
Topic Review
Nanozymes
Nanozymes are advanced nanomaterials which possess unique physicochemical properties with the precise structural fabrication capability to mimic intrinsic biologically relevant reactions.
  • 5.3K
  • 19 Jan 2021
Topic Review
Techniques for Emulsion Characterization
Emulsions have garnered significant attention within a variety of industries, including pharmaceuticals, food production, and cosmetics. The importance of emulsions across these sectors is attributed to their versatility and unique properties, such as increased interfacial area and the ability to deliver compounds insoluble in water or to mask the flavor of unpalatable ingredients. A comprehensive and precise assessment of the physicochemical properties, structural features, and stability of emulsions is an indispensable phase in the pursuit of new formulations and the improvement of manufacturing protocols. The characterization of emulsions encompasses an array of methodologies designed to determine their attributes, such as composition, texture, rheological and thermal properties, electrical conductivity, droplet size, size distribution, concentration, surface charge, and others.
  • 5.3K
  • 17 Feb 2024
Topic Review
Engine Control Unit
An engine control unit (ECU), also commonly called an engine control module (ECM) is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by reading values from a multitude of sensors within the engine bay, interpreting the data using multidimensional performance maps (called lookup tables), and adjusting the engine actuators. Before ECUs, air–fuel mixture, ignition timing, and idle speed were mechanically set and dynamically controlled by mechanical and pneumatic means. If the ECU has control over the fuel lines, then it is referred to as an electronic engine management system (EEMS). The fuel injection system has the major role of controlling the engine's fuel supply. The whole mechanism of the EEMS is controlled by a stack of sensors and actuators.
  • 5.3K
  • 14 Oct 2022
Topic Review
Mechanism of Action of Thiazolidin-2,4-dione
The thiazolidin-2,4-dione (TZD) moiety plays a central role in the biological functioning of several essential molecules. The availability of substitutions at the third and fifth positions of the Thiazolidin-2,4-dione (TZD) scaffold makes it a highly utilized and versatile moiety that exhibits a wide range of biological activities.
  • 5.3K
  • 18 Oct 2022
Topic Review
Vinca Leaves
Morphological and anatomical traits of the Vinca leaf were examined using microscopy techniques. Outdoor Vinca minor and V. herbacea plants and greenhouse cultivated V. major and V. major var. variegata plants had interspecific variations. All Vinca species leaves are hypostomatic. However, except for V. minor leaf, few stomata were also present on the upper epidermis. V. minor leaf had the highest stomatal index and V. major had the lowest, while the distribution of trichomes on the upper epidermis was species-specific. Differentiated palisade and spongy parenchyma tissues were present in all Vinca species’ leaves. However, V. minor and V. herbacea leaves had a more organized anatomical aspect, compared to V. major and V. major var. variegata leaves. Additionally, as a novelty, the cellular to intercellular space ratio of the Vinca leaf’s mesophyll was revealed herein with the help of computational analysis.
  • 5.3K
  • 06 Apr 2021
Topic Review
Trends of Current LNG Cold Energy Utilization
Liquified natural gas (LNG) is a clean primary energy source that is growing in popularity due to the distance between natural gas (NG)-producing countries and importing countries. The large amount of cold energy stored in LNG presents an opportunity for sustainable technologies to recover and utilize this energy. This can enhance the energy efficiency of LNG regasification terminals and the economic viability of the LNG supply chain. The energy stored in LNG in the form of low temperatures is referred to as cold energy. When LNG is regasified, or converted back into its gaseous form, this cold energy is released. This process involves heating the LNG, which causes it to vaporize and release its stored energy. LNG cold energy has been mostly utilized for power generation, air separation, traditional desalination, and cryogenics carbon dioxide capture. Other potential applications are also emerging such as for data center cooling and cold energy storage. The commercialization of sustainable technologies, such as improvement strategies for LNG cold energy utilization, is becoming increasingly important in the energy industry.
  • 5.3K
  • 20 Feb 2023
Topic Review
Proto-Romanian Language
Proto-Romanian (also known as "Common Romanian", româna comună or "Ancient Romanian", străromâna, Balkan Latin) is a hypothetical and unattested Romance language evolved from Vulgar Latin and considered to have been spoken by the ancestors of today's Romanians and related Balkan Latin peoples (Vlachs) before c. 900 (7th–11th century AD). In the 9th century Proto-Romanian already had a structure very distinct from the other Romance languages, with major differences in grammar, morphology and phonology and already was a member of the Balkan language area. Most of its features can be found in the modern Balkan Romance languages. It already contained around a hundred loans from Slavic languages, including words such as trup (body, flesh), as well as some Greek language loans via Vulgar Latin, but no Hungarian and Turkish words as these nations had yet to arrive in the region. According to the Romanian theory, it evolved into the following modern languages and their dialects: The first language that broke the unity was Aromanian, in the 9th century, followed shortly after by Megleno-Romanian. Istro-Romanian was the last to break the link with Daco-Romanian in the 11th century. The place where Proto-Romanian formed is still under debate; most historians put it just to the north of the Jireček Line. See: Origin of Romanians. The Roman occupation led to a Roman-Thracian syncretism, and similar to the case of other conquered civilisation (see Gallo-Roman culture developed in Roman Gaul), had as final result the Latinization of many Thracian tribes which were on the edge of the sphere of Latin influence, eventually resulting in the possible extinction of the Daco-Thracian language (unless, of course, Albanian is its descendant), but traces of it are still preserved in the Eastern Romance substratum. From the 2nd century AD, the Latin spoken in the Danubian provinces starts to display its own distinctive features, separate from the rest of the Romance languages, including those of western Balkans (Dalmatian). The Thraco-Roman period of the Romanian language is usually delimited between the 2nd century (or earlier via cultural influence and economic ties) and the 6th or the 7th century. It is divided, in turn, into two periods, with the division falling roughly in the 3rd to 4th century. The Romanian Academy considers the 5th century as the latest time that the differences between Balkan Latin and western Latin could have appeared, and that between the 5th and 8th centuries, the new language, Romanian, switched from Latin speech, to a vernacular Romance idiom, called Română comună.
  • 5.3K
  • 21 Nov 2022
Topic Review
Cylinder Block
The cylinder block is an integrated structure comprising the cylinder(s) of a reciprocating engine and often some or all of their associated surrounding structures (coolant passages, intake and exhaust passages and ports, and crankcase). The term engine block is often used synonymously with "cylinder block" (although technically distinctions can be made between en bloc cylinders as a discrete unit versus engine block designs with yet more integration that comprise the crankcase as well). In the basic terms of machine elements, the various main parts of an engine (such as cylinder(s), cylinder head(s), coolant passages, intake and exhaust passages, and crankcase) are conceptually distinct, and these items can all be made as discrete pieces that are bolted together. Such construction was very widespread in the early decades of the commercialization of internal combustion engines (1880s to 1920s), and it is still sometimes used in certain applications where it remains advantageous (especially very large engines, but also some small engines). However, it is no longer the normal way of building most petrol engines and diesel engines, because for any given engine configuration, there are more efficient ways of designing for manufacture (and also for maintenance and repair). These generally involve integrating multiple machine elements into one discrete part, and doing the making (such as casting, stamping, and machining) for multiple elements in one setup with one machine coordinate system (of a machine tool or other piece of manufacturing machinery). This yields lower unit cost of production (and/or maintenance and repair). Today most engines for cars, trucks, buses, tractors, and so on are built with fairly highly integrated design, so the words "monobloc" and "en bloc" are seldom used in describing them; such construction is often implicit. Thus "engine block", "cylinder block", or simply "block" are the terms likely to be heard in the garage or on the street.
  • 5.3K
  • 28 Sep 2022
Topic Review
Plasma
Plasma (from grc πλάσμα (plásma) 'moldable substance') is one of the four fundamental states of matter. It contains a significant portion of charged particles – ions and/or electrons. The presence of these charged particles is what primarily sets plasma apart from the other fundamental states of matter. It is the most abundant form of ordinary matter in the universe, being mostly associated with stars, including the Sun. It extends to the rarefied intracluster medium and possibly to intergalactic regions. Plasma can be artificially generated by heating a neutral gas or subjecting it to a strong electromagnetic field. The presence of charged particles makes plasma electrically conductive, with the dynamics of individual particles and macroscopic plasma motion governed by collective electromagnetic fields and very sensitive to externally applied fields. The response of plasma to electromagnetic fields is used in many modern technological devices, such as plasma televisions or plasma etching. Depending on temperature and density, a certain amount of neutral particles may also be present, in which case plasma is called partially ionized. Neon signs and lightning are examples of partially ionized plasmas. Unlike the phase transitions between the other three states of matter, the transition to plasma is not well defined and is a matter of interpretation and context. Whether a given degree of ionization suffices to call a substance 'plasma' depends on the specific phenomenon being considered.
  • 5.3K
  • 25 Nov 2022
Topic Review
Mountain Man
A mountain man is an explorer who lives in the wilderness. Mountain men were most common in the North American Rocky Mountains from about 1810 through to the 1880s (with a peak population in the early 1840s). They were instrumental in opening up the various Emigrant Trails (widened into wagon roads) allowing Americans in the east to settle the new territories of the far west by organized wagon trains traveling over roads explored and in many cases, physically improved by the mountain men and the big fur companies originally to serve the mule train based inland fur trade. They arose in a natural geographic and economic expansion driven by the lucrative earnings available in the North American fur trade, in the wake of the various 1806–07 published accounts of the Lewis and Clark expeditions' (1803–1806) findings about the Rockies and the (ownership-disputed) Oregon Country where they flourished economically for over three decades. By the time two new international treaties in early 1846 and early 1848 officially settled new western coastal territories in the United States and spurred a large upsurge in migration, the days of mountain men making a good living by fur trapping had largely ended. This was partly because the fur industry was failing due to reduced demand and over trapping. With the rise of the silk trade and quick collapse of the North American beaver-based fur trade in the later 1830s–1840s, many of the mountain men settled into jobs as Army Scouts or wagon train guides or settled throughout the lands which they had helped open up. Others, like William Sublette, opened up fort-trading posts along the Oregon Trail to service the remnant fur trade and the settlers heading west.
  • 5.3K
  • 11 Nov 2022
Topic Review
Axolotl (Ambystoma mexicanum)
The axolotl (Ambystoma mexicanum) is a neotenic amphibian belonging to the family Ambystomatidae, native to the ancient lakes of the Valley of Mexico. Distinguished by its retention of larval traits throughout adulthood, the axolotl exhibits extraordinary regenerative abilities, capable of regenerating limbs, spinal cord, heart, and portions of the brain. Its unique developmental biology and endangered status make it a model organism in evolutionary, genetic, and regenerative studies.
  • 5.3K
  • 10 Oct 2025
Topic Review
The Use of “Lifestyle” in Health Psychology
Lifestyle is a complex and often generic concept that has been used and defined in different ways in scientific research. There is no single definition of lifestyle, and various fields of knowledge have developed theories and research variables that are also distant from each other. In health psychology, the use of this concept has spread widely, especially in the preventive medicine sector, despite a definition that is not always precise and unambiguous. Indeed, it is often confused and assimilated to the health behaviours that have been defined as behavioural patterns, actions, and habits that relate to health maintenance, to health restoration and health improvement. There are two main definitions of lifestyles. The first one was formulated by the WHO, for which lifestyle is defined as “patterns of (behavioural) choices from the alternatives that are available to people according to their socio-economic circumstances and the ease with which they are able to choose certain ones over others”. The second major definition of lifestyle formulated by Cockerham is “collective patterns of health-related behaviour based on choices from options available to people according to their life chances”.
  • 5.3K
  • 09 Mar 2023
Topic Review
Carnitine in Mitochondrial Fatty Acid Transport and β-Oxidation
l-Carnitine is an amino acid derivative widely known for its involvement in the transport of long-chain fatty acids into the mitochondrial matrix, where fatty acid oxidation occurs. Moreover, l-Carnitine protects the cell from acyl-CoA accretion through the generation of acylcarnitines.
  • 5.3K
  • 11 Nov 2021
Topic Review
Bahá'í Faith on Life after Death
The Bahá'í Faith affirms the prospect of life after death extensively while not defining everything about it. The soul on death is said to recognize the value of its deeds and begin a new phase of a conscious relationship with God though negative experiences are possible. Others have noted the religion's stances on the afterlife.
  • 5.3K
  • 22 Nov 2022
Topic Review
Lane Detection and Tracking
Lane detection and tracking are the advanced key features of the advanced driver assistance system. Lane detection is the process of detecting white lines on the roads. Lane tracking is the process of assisting the vehicle to remain in the desired path, and it controls the motion model by using previously detected lane markers.
  • 5.3K
  • 25 Oct 2021
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