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Topic Review
Saltation
In biology, saltation (from la saltus 'leap, jump') is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation. This was historically offered as an alternative to Darwinism. Some forms of mutationism were effectively saltationist, implying large discontinuous jumps. Speciation, such as by polyploidy in plants, can sometimes be achieved in a single and in evolutionary terms sudden step. Evidence exists for various forms of saltation in a variety of organisms.
  • 5.8K
  • 29 Sep 2022
Topic Review
Public Parks
Public parks are a part of the public spaces of a city. Cities are rediscovering the potential of urban parks to advance environmental sustainability and enhance its social amenities.
  • 5.8K
  • 16 Jan 2022
Topic Review Peer Reviewed
Entropy
The concept of entropy constitutes, together with energy, a cornerstone of contemporary physics and related areas. It was originally introduced by Clausius in 1865 along abstract lines focusing on thermodynamical irreversibility of macroscopic physical processes. In the next decade, Boltzmann made the genius connection—further developed by Gibbs—of the entropy with the microscopic world, which led to the formulation of a new and impressively successful physical theory, thereafter named statistical mechanics. The extension to quantum mechanical systems was formalized by von Neumann in 1927, and the connections with the theory of communications and, more widely, with the theory of information were respectively introduced by Shannon in 1948 and Jaynes in 1957. Since then, over fifty new entropic functionals emerged in the scientific and technological literature. The most popular among them are the additive Renyi one introduced in 1961, and the nonadditive one introduced in 1988 as a basis for the generalization of the Boltzmann–Gibbs and related equilibrium and nonequilibrium theories, focusing on natural, artificial and social complex systems. Along such lines, theoretical, experimental, observational and computational efforts, and their connections to nonlinear dynamical systems and the theory of probabilities, are currently under progress. Illustrative applications, in physics and elsewhere, of these recent developments are briefly described in the present synopsis.
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  • 07 May 2022
Topic Review
Egyptian Medical Papyri
Egyptian medical papyri are ancient Egyptian texts written on papyrus which permit a glimpse at medical procedures and practices in ancient Egypt. The papyri give details on disease, diagnosis, and remedies of disease, which include herbal remedies, surgery, and magical spells. It is thought there were more medical papyri, but many have been lost due to grave robbing. The largest study of the medical papyri to date has been undertaken by Humboldt University of Berlin and was titled Medizin der alten Ägypter ("Medicine of ancient Egypt"). Early Egyptian medicine was based mostly on a mixture of magic and religious spells. Most commonly "cured" by use of amulets or magical spells, the illnesses were thought to be caused by spiteful behavior or actions. Afterwards, doctors performed various medical treatments if necessary. The instructions for these medical rituals were later inscribed on papyrus scrolls by the priests performing the actions.
  • 5.8K
  • 07 Nov 2022
Topic Review
Transmission (Mechanics)
A transmission is a machine in a power transmission system, which provides controlled application of power. Often the term 5-speed transmission refers simply to the gearbox, that uses gears and gear trains to provide speed and torque block conversions from a rotating power source to another device. The term transmission properly refers to the whole drivetrain, including clutch, gearbox, prop shaft (for rear-wheel drive vehicles), differential, and final drive shafts. In the United States the term is sometimes used in casual speech to refer more specifically to the gearbox alone, and detailed usage differs. The most common use is in motor vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process. Transmissions are also used on pedal bicycles, fixed machines, and where different rotational speeds and torques are adapted. Often, a transmission has multiple gear ratios (or simply "gears") with the ability to switch between them as the speed varies. This switching may be done manually (by the operator) or automatically (by a control unit). Directional (forward and reverse) control may also be provided. Single-ratio transmissions also exist, which simply change the speed and torque (and sometimes direction) of motor output. In motor vehicles, the transmission generally is connected to the engine crankshaft via a flywheel or clutch or fluid coupling, partly because internal combustion engines cannot run below a particular speed. The output of the transmission is transmitted via the driveshaft to one or more differentials, which drive the wheels. While a differential may also provide gear reduction, its primary purpose is to permit the wheels at either end of an axle to rotate at different speeds (essential to avoid wheel slippage on turns) as it changes the direction of rotation. Conventional gear/belt transmissions are not the only mechanism for speed/torque adaptation. Alternative mechanisms include torque converters and power transformation (e.g. diesel-electric transmission and hydraulic drive system). Hybrid configurations also exist. Automatic transmissions use a valve body to shift gears using fluid pressures in response to engine RPM, speed, and throttle input.
  • 5.8K
  • 01 Nov 2022
Topic Review
Lagrangian Point
In celestial mechanics, the Lagrangian points (/ləˈɡrɑːndʒiən/ also Lagrange points, L-points, or libration points) are the points near two large bodies in orbit where a smaller object will maintain its position relative to the large orbiting bodies. At other locations, a small object would go into its own orbit around one of the large bodies, but at the Lagrangian points the gravitational forces of the two large bodies, the centripetal force of orbital motion, and (for certain points) the Coriolis acceleration all match up in a way that cause the small object to maintain a stable or nearly stable position relative to the large bodies. There are five such points, labeled L1 to L5, all in the orbital plane of the two large bodies, for each given combination of two orbital bodies. For instance, there are five Lagrangian points L1 to L5 for the Sun–Earth system, and in a similar way there are five different Lagrangian points for the Earth–Moon system. L1, L2, and L3 are on the line through the centers of the two large bodies, while L4 and L5 each act as the third vertex of an equilateral triangle formed with the centers of the two large bodies. L4 and L5 are stable, which implies that objects can orbit around them in a rotating coordinate system tied to the two large bodies. Several planets have trojan satellites near their L4 and L5 points with respect to the Sun. Jupiter has more than a million of these trojans. Artificial satellites have been placed at L1 and L2 with respect to the Sun and Earth, and with respect to the Earth and the Moon. The Lagrangian points have been proposed for uses in space exploration.
  • 5.8K
  • 17 Nov 2022
Topic Review
Belief
In sociology, the concept of beliefs refers to the mental acceptance or conviction that certain statements or propositions are true. Beliefs are subjective and personal convictions that individuals hold about the nature of reality, the social world, and various aspects of life. These cognitive constructs play a fundamental role in shaping human behavior, influencing decision-making processes, and contributing to the formation of individual and collective identities within a society.
  • 5.8K
  • 25 Jan 2024
Topic Review
Carcharodontosaurus
Carcharodontosaurus (/ˌkɑːrkəroʊˌdɒntoʊˈsɔːrəs/; lit. sharp-toothed lizard) is a genus of large carcharodontosaurid theropod dinosaur that existed during the Cenomanian age of the Late Cretaceous in Northern Africa. The genus Carcharodontosaurus is named after the shark genus Carcharodon, itself composed of the Greek karchar[os] (κάρχαρος, meaning "jagged" or "sharp") and odōn (ὀδών, "teeth"), and the suffix -saurus ("lizard"). It is currently known to have two species: C. saharicus and C. iguidensis.
  • 5.8K
  • 09 Nov 2022
Topic Review
Environmental Awareness and Individual’s Altruism
Environmental awareness is the level of how much people are interested in or care about environmental issues. Environmental awareness can be either local or global one depending on the type of environmental problem. Studies have argued that this awareness tends to be related to an individual’s altruism, which is one’s action that benefits others without expecting some kind of external reward. The connection between environmental awareness and altruism is getting attention from scholars since both concepts are prosocial ones but it is uncertain if people who are highly aware of environmental issues may not be always acting altruistically. However, it is likely that altruistic people are more likely to have high environmental awareness.
  • 5.8K
  • 28 Oct 2020
Topic Review
Tumbling Mills
Tumbling mills have been widely implemented in many industrial sectors for the grinding of bulk materials. They have been used for decades in the production of fines and in the final stages of ore comminution, where optimal levels for the enrichment particles’ sizes are obtained. Even though these ubiquitous machines of relatively simple construction have been subjected to extensive studies, the industry still struggles with a very low energy efficiency of the comminution process. Moreover, obtaining an optimal size for the grinding product particles is crucial for the effectiveness of the following processes and waste production reduction. New, innovative processing methods and machines are being developed to tackle the problem; however, tumbling mills are still most commonly used in all ranges of the industry. Since heavy equipment retrofitting is the most costly approach, process optimization with dedicated models and control systems is the most preferable solution for energy consumption reduction. While the classic technological measurements in mineral processing are well adopted by the industry, nowadays research focuses on new methods of the mill’s internal dynamics analysis and control.
  • 5.8K
  • 19 Jan 2021
Topic Review
Post-Translational Modification
Post-translational modifications (PTMs) add a layer of complexity to the proteome through the addition of biochemical moieties to specific residues of proteins, altering their structure, function and/or localization. Mass spectrometry (MS)-based techniques are at the forefront of PTM analysis due to their ability to detect large numbers of modified proteins with a high level of sensitivity and specificity.
  • 5.8K
  • 29 Apr 2021
Topic Review
Tata Nano Singur Controversy
The Tata Nano Singur controversy was a controversy generated by land acquisition of a proposed Tata Motors automobile factory at Singur in Hooghly district, West Bengal, India. The factory would have been used to build the compact car Tata Nano. Tata Motors started constructing a factory to manufacture a car, Tata Nano which was estimated to cost $2,500 at Singur. The small car was scheduled to roll out of the factory by 2008. The state government of West Bengal created the controversy by citing the 1894 land acquisition act rule to conduct an eminent domain takeover of 997 acres (4.03 km2) of farmland on which Tata Motors was supposed to build its factory. The rule is meant for public improvement projects, and the West Bengal government wanted Tata to build in its state. The project was opposed by activists and opposition parties in Bengal.
  • 5.8K
  • 19 Oct 2022
Topic Review
Mortal Kombat
Mortal Kombat is an American media franchise centered on a series of video games, originally developed by Midway Games in 1992. The development of the first game was originally based on an idea that Ed Boon and John Tobias had of making a video game starring Jean-Claude Van Damme, but as that idea fell through, a fantasy-themed fighting game was created instead, nonetheless paying homage to him with nut-cracking movie star character Johnny Cage, whose initials and personal style echo Van Damme's. Mortal Kombat was the first ever fighting game to introduce a secret fighter, reached if the player fulfilled a set of requirements. The original game has spawned many sequels and spin-offs consisting of several action-adventure games, as well as a comic book series and a card game. Film producer Lawrence Kasanoff licensed the rights to the game in the early 1990s and produced the first hit movie ever made from a video game. Lawrence also produced the second movie, animated TV series, live-action TV series films, the first one million platinum-selling album and a live-action tour. Mortal Kombat has become the most successful fighting franchise in the history of video games and one of the highest-grossing media franchises of all time. The series has a reputation for high levels of graphic violence, including, most notably, its Fatalities (finishing moves allowing the player to finish off their defeated opponent). Controversies surrounding Mortal Kombat, in part, led to the creation of the ESRB video game rating system. Early games in this series were also noted for their realistic digitized sprites and an extensive use of palette swapping to create new characters. Following Midway's bankruptcy, the Mortal Kombat development team was acquired by Warner Bros. Entertainment and turned into NetherRealm Studios.
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  • 19 Oct 2022
Topic Review
Mechanical Properties of Reinforced Bioplastics
Bioplastics are a type of plastic material that is bio-based, biodegradable, or both, depending on the source from which they were created.
  • 5.8K
  • 19 Sep 2022
Topic Review
Bitcoin Core
Bitcoin Core is free and open-source software that serves as a bitcoin node (the set of which form the bitcoin network) and provides a bitcoin wallet which fully verifies payments. It is considered to be bitcoin's reference implementation. Initially, the software was published by Satoshi Nakamoto under the name "Bitcoin", and later renamed to "Bitcoin Core" to distinguish it from the network. For this reason, it is also known as the Satoshi client. The MIT Digital Currency Initiative funds some of the development of Bitcoin Core. The project also maintains the cryptography library libsecp256k1.
  • 5.8K
  • 09 Nov 2022
Topic Review
Unbibium
Unbibium /uːnˈbɪbiəm/, also known as eka-thorium or simply element 122, is the currently hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to follow unbiunium as the second element of the superactinides, or the g-block and the fourth element of the 8th period. It has attracted recent attention, for similarly to unbiunium, it is expected to fall within the range of the island of stability. Despite many attempts, unbibium has not yet been synthesized, and therefore no natural isotopes have been found to exist. It is currently predicted that it has a g-orbital, the second element of which to have such besides unbiunium, which also has yet to be synthesized. It will most likely require nuclear fission to be produced artificially. In 2008, it was claimed to have been discovered in natural thorium samples but that claim has now been dismissed by recent repetitions of the experiment using more accurate techniques.
  • 5.8K
  • 29 Nov 2022
Topic Review Peer Reviewed
Structural Systems for Tall Buildings
Structural systems for tall buildings have gone through an evolutionary process. The rigid frame became popular in the first half of the 20th century but proved to be structurally inefficient beyond a certain height of tall buildings. The invention of the tubular structure in the 1960s allowed buildings to be built taller with low material consumption. Due to the obstructive nature of the closely spaced exterior columns of framed tubes and bracings of braced tubes, the core-outrigger system gained acceptance by the architects as it allowed them to freely articulate the façade design. However, the conventional tubular structures continued to retain their use for tall buildings to a lesser degree and later underwent a resurgence in modified forms. These and other advanced tubular forms in cutting-edge structural systems developed later continue to find application in modern times. This study presents a detailed narrative of different structural systems for tall buildings that is expected to assist structural engineers and architects to collaboratively select appropriate structural systems for tall buildings. 
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  • 08 Jul 2022
Topic Review
Advantages and Disadvantages of Hydrogen Trains
Hydrogen and electric drives used in various means of transport is a leading topic in many respects.
  • 5.8K
  • 20 Jun 2025
Topic Review Peer Reviewed
Non-Patent Literature
Non-patent literature is defined as scientific publications, technical standards, conference proceedings, clinical trials, books, manuals, technical or research reports, or any other technical scientific material which is cited in patents to show what has already been published and disseminated about the invention to be patented, in order to justify its novelty. These documents are considered technically relevant to the patent granting procedure and are cited along with other patents related to the same subject matter. 
  • 5.8K
  • 13 Apr 2022
Topic Review
Procedures for Extraction of Anthocyanins from Different Food
Anthocyanins are water-soluble pigments characterized by various intense colors found in fruits and vegetables. The extraction and separation of anthocyanins from plants is important, especially due to the instability of plant anthocyanins, selecting and optimizing. Anthocyanins are prone to degradation by several factors, including pH, temperature, oxygen, water activity, co-pigments and enzymes. Unwanted compounds, such as sugars, proteins, lipids, acids and other flavonoids, can also be removed from plant material by appropriate extraction methods. The most used method for anthocyanin extraction is the conventional one, solid–liquid extraction, also known as solvent extraction, during which anthocyanins can be dissolved in polar solvents (methanol/glycolic acid and acetone), followed by their quantification, achieved by using spectrophotometry, the differential pH method, which is a rapid and convenient quantitative assay. Starting from this point, it has developed and there are many anthocyanin-extraction methods, such as conventional solvent extraction (CSE), enzyme-assisted extraction (EAE), fermentation extraction (FE), supercritical fluid extraction (SFE) (CO2) extraction, microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE), high-hydrostatic-pressure extraction (HHPE) and pressurized-liquid extraction (PLE). One of the most frequent techniques for obtaining anthocyanins from plants is conventional solvent extraction. In order to meet the demands of safety and environmental sustainability, new extraction technologies with shorter extraction periods and higher yields have been developed (e.g., PLE, EFS, UAE, MAE, EAE, etc.).
  • 5.8K
  • 29 Nov 2022
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