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Topic Review
List of Intel Pentium 4 Microprocessors
The Pentium 4 microprocessor from Intel is a seventh-generation CPU targeted at the consumer market.
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  • 02 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.
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  • 18 Oct 2022
Topic Review
Amperometric Biosensors
Amperometric biosensors utilizing oxidoreductases were classified into three generations: 1st generation biosensors employing oxidases based on the electrocatalytic monitoring of substrate consumption or product formation, 2nd generation biosensors employing oxidases or dehydrogenases based on the electrocatalytic recycling of suitable redox mediators, and 3rd generation biosensors employing oxidoreductases capable of direct electron transfer to bare or modified electrodes.
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  • 16 Aug 2021
Topic Review
List of German Aircraft Projects, 1939–45
The aircraft in this list include prototype versions of aircraft used by the German Luftwaffe during World War II and unfinished wartime experimental programmes. In the former, development can stretch back to the 1920s and in the latter the project must have started between 1939-1945.
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  • 14 Oct 2022
Topic Review
The Related Metabolic Diseases and Treatments of Obesity
Obesity is a chronic disease characterized by the abnormal or excessive accumulation of body fat. Obesity is commonly associated with other metabolic disorders, such as type 2 diabetes, non-alcoholic fatty liver disease, cardiovascular diseases, chronic kidney disease, and cancers. Factors such as a sedentary lifestyle, overnutrition, socioeconomic status, and other environmental and genetic conditions can cause obesity. Many molecules and signaling pathways are involved in the pathogenesis of obesity. 
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  • 01 Sep 2022
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.
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  • 02 Nov 2022
Topic Review
Nanocellulose
Nanocellulose can be used to improve the mechanical properties of cementitious materials if a proper dosage is used. Nanocellulose can be used as a type of viscosity-modifying agent (VMA) in cementitious materials. Nanocellulose with a proper dosage can reduce the shrinkage of cementitious materials, especially with a low water-to-cement (w/c) ratio. Four types of nanocelluloses, including cellulose nanocrystal, cellulose nanofibril, bacterial cellulose, and cellulose filament, have been used in cementitious materials.
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  • 25 Dec 2020
Topic Review
Serendipity as a strategic advantage
Serendipity is defined as an ability to notice, evaluate, and take advantage of unexpected information for survival purposes (both natural and social). Based on this definition, Nancy K. Napier and Vuong Quan Hoang propose a framework to develop the notion of serendipity as a strategic advantage (or competitive advantage), both in practice and in research.
  • 5.4K
  • 06 May 2024
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.
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  • 21 Nov 2022
Biography
Mario J. Molina
Mario José Molina-Pasquel Henríquez (born March 19, 1943) is a Mexican chemist. He played a pivotal role in the discovery of the Antarctic ozone hole, and was a co-recipient of the 1995 Nobel Prize in Chemistry for his role in elucidating the threat to the Earth's ozone layer of chlorofluorocarbon (CFC) gases. He became the first Mexican-born citizen to receive a Nobel Prize in Chemistry.[1]
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  • 29 Nov 2022
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”.
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  • 09 Mar 2023
Topic Review
Hatha Yoga
Hatha yoga is a branch of Yoga, one of the six schools of Hinduism. The word haṭha literally means "force" and thus alludes to a system of physical techniques.:770:527 In India hatha yoga is associated in popular tradition with the 'Yogis' of the Natha Sampradaya through its mythical founder Matsyendranath. Matsyendranath, also known as Minanath or Minapa in Tibet, is celebrated as a saint in both Buddhist and Hindu tantric and hatha yoga schools. However, James Mallinson associates hatha yoga with the Dashanami Sampradaya and the mystical figure of Dattatreya. According to the Dattatreya Yoga Śastra, there are two forms of hatha yoga: one practiced by Yajñavalkya consisting of the eight limbs of ashtanga yoga and another practiced by Kapila consisting of eight mudras. Currently, the oldest dated text to describe hatha yoga, the Amṛtasiddhi, comes from a tantric Buddhist milieu. The oldest texts to use the actual verbiage of hatha are also Vajrayana Buddhist. In the 20th century, hatha yoga, particularly asanas (the physical postures), became popular throughout the world as a form of physical exercise, and is now colloquially termed simply as "yoga."
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  • 24 Nov 2022
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.
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  • 15 Nov 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.
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  • 29 Oct 2020
Topic Review
Will
Will, generally, is a faculty of the mind - within philosophy, will is important as one of the parts of the mind, along with reason and understanding. It is considered central to the field of ethics because of its role in enabling deliberate action. One of the recurring questions discussed in the Western philosophical tradition is that of free will - and the related, but more general notion of fate - which asks how the will can be truly free if a person's actions have either natural or divine causes which determine them. In turn, this is directly connected to discussions on the nature of freedom and to the problem of evil.
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  • 11 Oct 2022
Topic Review
Active Pixel Sensor
An active-pixel sensor (APS) is an image sensor where each picture element ("pixel") has a photodetector and an active amplifier. There are many types of integrated circuit active pixel sensors including the complementary metal–oxide–semiconductor (CMOS) APS used most commonly in cell phone cameras, web cameras, most digital pocket cameras since 2010, in most digital single-lens reflex cameras (DSLRs) and Mirrorless interchangeable-lens cameras (MILCs). Such an image sensor is produced using CMOS technology (and is hence also known as a CMOS sensor), and has emerged as an alternative to charge-coupled device (CCD) image sensors. The term 'active pixel sensor' is also used to refer to the individual pixel sensor itself, as opposed to the image sensor; in that case the image sensor is sometimes called an active pixel sensor imager, or active-pixel image sensor.
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  • 23 Nov 2022
Topic Review Peer Reviewed
Geometric Design of Suburban Roundabouts
A modern roundabout is an intersection with a circulatory roadway at which the vehicle speed is low, and the traffic is continuous and circulating in one direction around the central island towards the exits at the approach legs. Modern roundabout design is an iterative process that is composed of the following steps: (1) the identification of the roundabout as the optimal traffic solution; (2) the definition of the number of lanes at the intersection based on the required capacity and the level of service; (3) the initial design of the roundabout geometry; (4) design vehicle swept path, the fastest path analysis, and visibility performance checks; and (5) detailed roundabout design if the results of the performance checks are in line with the design recommendations. Initial roundabout geometry design elements are not independent of each other; therefore, care must be taken to provide compatibility between them. An overview and a comparative analysis of the initial geometric design elements for suburban single-lane roundabouts defined in roundabout design guidelines and norms used in Croatia, Austria, France, the Netherlands, Germany, Serbia, and Switzerland is given in this entry.
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  • 13 Apr 2022
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.
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  • 14 Oct 2022
Topic Review
Loopholes in Bell Tests
In Bell tests, there may be problems of experimental design or set-up that affect the validity of the experimental findings. These problems are often referred to as "loopholes". See the article on Bell's theorem for the theoretical background to these experimental efforts (see also John Stewart Bell). The purpose of the experiment is to test whether nature is best described using a local hidden-variable theory or by the quantum entanglement theory of quantum mechanics. The "detection efficiency", or "fair sampling" problem is the most prevalent loophole in optical experiments. Another loophole that has more often been addressed is that of communication, i.e. locality. There is also the "disjoint measurement" loophole which entails multiple samples used to obtain correlations as compared to "joint measurement" where a single sample is used to obtain all correlations used in an inequality. To date, no test has simultaneously closed all loopholes. Ronald Hanson of the Delft University of Technology claims the first Bell experiment that closes both the detection and the communication loopholes. (This was not an optical experiment in the sense discussed below; the entangled degrees of freedom were electron spins rather than photon polarization.) Nevertheless, correlations of classical optical fields also violate Bell's inequality. In some experiments there may be additional defects that make "local realist" explanations of Bell test violations possible; these are briefly described below. Many modern experiments are directed at detecting quantum entanglement rather than ruling out local hidden-variable theories, and these tasks are different since the former accepts quantum mechanics at the outset (no entanglement without quantum mechanics). This is regularly done using Bell's theorem, but in this situation the theorem is used as an entanglement witness, a dividing line between entangled quantum states and separable quantum states, and is as such not as sensitive to the problems described here. In October 2015, scientists from the Kavli Institute of Nanoscience reported that the quantum nonlocality phenomenon is supported at the 96% confidence level based on a "loophole-free Bell test" study. These results were confirmed by two studies with statistical significance over 5 standard deviations which were published in December 2015. However, Alain Aspect writes that No experiment can be said to be totally loophole-free.
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  • 31 Oct 2022
Topic Review
Orthographic Ligature
In writing and typography, a ligature occurs where two or more graphemes or letters are joined as a single glyph. An example is the character æ as used in English, in which the letters a and e are joined. The common ampersand (&) developed from a ligature in which the handwritten Latin letters e and t (spelling et, from the Latin for "and") were combined.
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  • 01 Nov 2022
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