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Topic Review
Olmec Influences on Mesoamerican Cultures
The causes and degree of Olmec influences on Mesoamerican cultures has been a subject of debate over many decades. Although the Olmecs are considered to be perhaps the earliest Mesoamerican civilization, there are questions concerning how and how much the Olmecs influenced cultures outside the Olmec heartland. This debate is succinctly, if simplistically, framed by the title of a 2005 The New York Times article: “Mother Culture, or Only a Sister?”.
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  • 14 Oct 2022
Topic Review
Antibiotic Susceptibility Testing
Antibiotic susceptibility testing (AST) specifies effective antibiotic dosage and formulates a profile of empirical therapy for the proper management of an individual patient’s health against deadly infections. Therefore, rapid diagnostic plays a pivotal role in the treatment of bacterial infection.
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  • 03 Jan 2022
Topic Review
Echoic Memory
Echoic memory is the sensory memory that registers specific to auditory information (sounds). Once an auditory stimulus is heard, it is stored in memory so that it can be processed and understood. Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over. Since echoic memories are heard once, they are stored for slightly longer periods of time than iconic memories (visual memories). Auditory stimuli are received by the ear one at a time before they can be processed and understood. For instance, hearing the radio is very different from reading a magazine. A person can only hear the radio once at a given time, while the magazine can be read over and over again. It can be said that the echoic memory is like a "holding tank" concept, because a sound is unprocessed (or held back) until the following sound is heard, and only then can it be made meaningful. This particular sensory store is capable of storing large amounts of auditory information that is only retained for a short period of time (3–4 seconds). This echoic sound resonates in the mind and is replayed for this brief amount of time shortly after being heard. Echoic memory encodes only moderately primitive aspects of the stimuli, for example pitch, which specifies localization to the non-association brain regions.
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  • 21 Oct 2022
Topic Review
Cartorhynchus
Cartorhynchus (meaning "shortened snout") is an extinct genus of early ichthyosauriform marine reptile that lived during the Early Triassic epoch, about 248 million years ago. The genus contains a single species, Cartorhynchus lenticarpus, named in 2014 by Ryosuke Motani and colleagues from a single nearly-complete skeleton found near Chaohu, Anhui Province, China . Along with its close relative Sclerocormus, Cartorhynchus was part of a diversification of marine reptiles that occurred suddenly (over about one million years) during the Spathian substage, soon after the devastating Permian-Triassic extinction event, but they were subsequently driven to extinction by volcanism and sea level changes by the Middle Triassic. Measuring about 40 centimetres (16 in) long, Cartorhynchus was small animal with a lizard-like body and a short torso; it probably swam in an eel-like manner at slow speeds. Its limbs bore extensive cartilage and could bend like flippers, which may have allowed it to walk on land. The most distinctive features of Cartorhynchus were its short, constricted snout, and its multiple rows of molar-like teeth which grew on the inside surface of its jaw bones. These teeth were not discovered until the specimen was subjected to CT scanning. Cartorhynchus likely preyed on hard-shelled invertebrates using suction feeding, although how it exactly used its inward-directed teeth is not yet known. It was one of up to five independent acquisitions of molar-like teeth among ichthyosauriforms.
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  • 04 Nov 2022
Topic Review
Sustainable Development Goals
Sürdürülebilir kalkınma hedefleri (SDG'ler), 2015'te kabul edilen 17 hedefi içeren, BM'nin herkes için daha iyi ve daha sürdürülebilir bir gelecek elde etme planının küresel bir kalkınma programıdır. Yoksulluk, eşitsizlik, iklim değişikliği dahil olmak üzere küresel nüfusun karşılaştığı zorlukları ele alırlar. , çevresel bozulma, barış ve adalet. Programlar genellikle sürdürülebilir ekonomik büyümeyi ve sürdürülebilir kalkınma için 2030 gündemini uygulamak için sürdürülebilirliğin güçlendirilmesi modlarını vurgular. Bu SDG'lerden SDGS 7, 8, 9, 11, 12 ve 17, doğrudan ve/veya dolaylı olarak sürdürülebilirlik ve döngüsellik fenomeniyle bağlantılıdır. Birleşmiş Milletler'in (BM) SKH'lerine imza atan ülkelerdeki hükümetler, ulusal politika ve programlar da dahil olmak üzere farklı eylemlerde bulunarak hedefe ulaşılmasında çok önemli bir rol oynamaktadır,
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  • 03 Nov 2022
Topic Review
Protein Folding: Enigma and Solution
Protein folding is a process that converts the unfolded, disordered protein chain into a chain having a definite, unique three-dimensional structure.
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  • 23 Apr 2021
Topic Review Peer Reviewed
Modulation of the Host Defence System by Nematophagous Fungi and Chitosan
Nematophagous fungi (NFs), which are responsible for soil suppression of plant-parasitic nematodes, are multitrophic biocontrol agents. This raises the question of the transition between lifestyles (e.g., endophytism vs. egg parasitism). The NF Pochonia chlamydosporia colonises food crops and promotes their growth and yield. When colonising the plant, P. chlamydosporia induces the plant immunity (PI). However, it also evades the PI. To do this, both endophytic NF and pathogenic fungi (PF) secrete LysM effectors (LysM-effs). LysM effectors have been shown to have diverse functions in different organisms, including the protection of fungal chitin from plant chitinases. P. chlamydosporia is resistant to chitosan, which modulates gene expression in fungi and plants and has antimicrobial properties. P. chlamydosporia chitin deacetylases (CDA) and chitosanases (CSN) also help P. chlamydosporia evade plant immunity, resist exogenous chitosan, and are induced during fungal infection of nematode eggs. NF-chitosan formulations are new biomanagement tools against plant parasitic nematodes, fungal wilt pathogens and insect pests that currently threaten food security crops. Furthermore, omics techniques are useful tools to elucidate the role of CDAs, CSNs, LysM-effs, adhesion proteins and carbohydrate-active enzymes in pathogen–BCA–plant interactions, adhesion and infection to nematode eggs and their modulation by chitosan.
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  • 21 Feb 2024
Topic Review
Seaweed Polysaccharide Based Products/Materials
Among the various natural polymers, polysaccharides are one of the oldest biopolymers present on the earth. They play a very crucial role in the survival of both animals and plants. Due to the presence of hydroxyl functional groups in most of the polysaccharides, it is easy to prepare their chemical derivatives. Several polysaccharide derivatives are widely used in a number of industrial applications. The polysaccharides such as cellulose, starch, chitosan, etc. have several industrial applications but due to some distinguished characteristic properties, seaweed polysaccharides are preferred in a number of applications.
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  • 17 Sep 2021
Topic Review
Bispecific Antibodies in Cancer Immunotherapy
Immunotherapy has redefined the treatment of cancer patients and it is constantly generating new advances and approaches. Among the multiple options of immunotherapy, bispecific antibodies (bsAbs) represent a novel thoughtful approach. These drugs integrate the action of the immune system in a strategy to redirect the activation of innate and adaptive immunity toward specific antigens and specific tumor locations.
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  • 22 Jun 2022
Topic Review
Ajativada
Ajātivāda is the fundamental philosophical doctrine of the Advaita Vedanta philosopher Gaudapada. According to Gaudapada, the Absolute is not subject to birth, change and death. The Absolute is aja, the unborn eternal. The empirical world of appearances is considered unreal, and not absolutely existent. Gaudapada's perspective is based on the Mandukya Upanishad, applying the philosophical concept of "ajāta" to the inquiry of Brahman, showing that Brahman wholly transcends the conventional understanding of being and becoming. The concept is also found in Madhyamaka Buddhism, as the theory of nonorigination.
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  • 04 Nov 2022
Topic Review
SU(2)/SU(3) Quantum Yang-Mills theory Thermodynamics
An outline of the main, purely theoretical ideas involved in Quantum Yang-Mills thermodynamics is given and implications thereof for applications in cosmology, particle, plasma, and condensed-matter physics are sketched. On the theoretical side, we elucidate the concepts of the thermal ground states of the deconfining and preconfining phases together with their gauge-mode excitations , and we discuss the quantum vacuum of the confining phase including its finite-extent excitations. On the application side, we briefly mention how deconfining SU(2) Yang-Mills thermodynamics, when postulated to describe thermal photon gases, predicts a modified temperature (T) -redshift (z) relation for the Cosmic Microwave Background (CMB) which, in turn, implies a rearrangement of the dark sector well before the onset of nonlinear structure formation. All-z fits of the ensuing cosmological model to the observed angular power spectra  (CMB) yield a value for the present Hubble parameter H0 agreeing with that extracted from local distance measurements, a baryon density of the present Universe being about 30% smaller than the standard value obtained from Big-Bang-Nucleosynthesis (BBN) but matching direct censuses, and a late onset of reionisation of the Universe agreeing with the observation of the Gunn-Peterson trough in high-z quasar spectra. We also mention how the three lepton families of the Standard Model of Particle Physics (SMPP) could emerge as solitons immersed into the confining  phases of three SU(2) Yang-Mills theories, subject to mixing of their Cartan subalgebras. In particular, the electron and its neutrino would be represented by 1-fold selfintersecting and single, stable center-vortex loops with a wealth of implications for strongly correlated charge carriers in the two spatial dimensions of  certain condensed-matter systems as well as ultra hot plasmas.
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  • 30 Oct 2020
Topic Review
Hesperidin and SARS-CoV-2
Among the flavonoids, hesperidin has recently attracted the attention of researchers, because it binds to the key proteins of the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several computational methods, independently applied by different researchers, showed that hesperidin has a low binding energy, both with the coronavirus “spike” protein, and with the main protease that transforms the early proteins of the virus into the complex responsible for viral replication. The binding energy of hesperidin to these important components is lower than that of lopinavir, ritonavir, and indinavir, suggesting that it could perform an effective antiviral action. Furthermore, both hesperidin and ascorbic acid counteract the cell damaging effects of the oxygen free radicals triggered by virus infection and inflammation.
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  • 26 Oct 2020
Topic Review
DNV GL
DNV GL is an international accredited registrar and classification society headquartered in Høvik, Norway . The company currently has about 14,500 employees and 350 offices operating in more than 100 countries, and provides services for several industries including maritime, renewable energy, oil & gas, electrification, food & beverage and healthcare. It was created in 2013 as a result of a merger between two leading organizations in the field — Det Norske Veritas (Norway ) and Germanischer Lloyd (Germany ). DNV GL is the world's largest classification society, providing services for 13,175 vessels and mobile offshore units (MOUs) amounting to 265.4 million gt, which represents a global market share of 21%. It is also the largest technical consultancy and supervisory to the global renewable energy (particularly wind, wave, tidal and solar) and oil and gas industry — 65% of the world's offshore pipelines are designed and installed to DNV GL's technical standards. Prior to the merger, both DNV and GL have independently acquired several companies in different sectors, such as Hélimax Energy (Canada), Garrad Hassan (UK), Windtest (Germany) and KEMA (Netherlands), which now contribute to DNV GL's expertise across several industries. In addition to providing services such as technical assessment, certification, risk management and software development, DNV GL also invests heavily in research. Remi Eriksen took over as Group President and CEO of DNV GL on August 1, 2015, succeeding Henrik O. Madsen.
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  • 02 Dec 2022
Topic Review
Trace Gas Orbiter
The ExoMars Trace Gas Orbiter (TGO or ExoMars Orbiter) is a collaborative project between the European Space Agency (ESA) and Roscosmos that sent an atmospheric research orbiter and the Schiaparelli demonstration lander to Mars in 2016 as part of the European-led ExoMars programme. The Trace Gas Orbiter delivered the Schiaparelli lander on 16 October 2016, which crashed on the surface. The orbiter began aerobraking in March 2017 to lower its initial orbit of 200 by 98,000 km (120 by 60,890 mi). Aerobraking concluded on 20 February 2018 when a final thruster firing resulted in an orbit of 200 by 1,050 km (120 by 650 mi). Additional thruster firings every few days raised the orbiter to a circular "science" orbit of 400 km (250 mi), which was achieved on 9 April 2018. A key goal is to gain a better understanding of methane (CH4) and other trace gases present in the Martian atmosphere that could be evidence for possible biological activity. The programme will follow with the Kazachok lander and the Rosalind Franklin rover in 2020, which will search for biomolecules and biosignatures; the TGO will operate as the communication link for the ExoMars lander and rover and provide communication for other Mars surface probes with Earth.
  • 3.0K
  • 27 Oct 2022
Topic Review
Mechanochemical Synthesis of Nanoparticles
Various solvent-based approaches have been already used to synthesize porous materials. Mechanochemical synthesis is one of the effective eco-friendly alternatives to the conventional synthesis. It adopts the efficient mixing of reactants using ball milling without or with a very small volume of solvents, gives smaller size nanoparticles (NPs) and larger surface area, and facilitates their functionalization, which is highly beneficial for antimicrobial applications.
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  • 15 Mar 2023
Topic Review
Endophytic Fungi
An extensive literature search was performed to review current knowledge about endophytic fungi isolated from plants included in the European Food Safety Authority (EFSA) dossier. The selected genera of plants were Acacia, Albizia, Bauhinia, Berberis, Caesalpinia, Cassia, Cornus, Hamamelis, Jasminus, Ligustrum, Lonicera, Nerium, and Robinia. A total of 120 fungal genera have been found in plant tissues originating from several countries. Bauhinia and Cornus showed the highest diversity of endophytes, whereas Hamamelis, Jasminus, Lonicera, and Robinia exhibited the lowest. The most frequently detected fungi were Aspergillus, Colletotrichum, Fusarium, Penicillium, Phyllosticta, and Alternaria. Plants and plant products represent an inoculum source of several mutualistic or pathogenic fungi, including quarantine pathogens. Thus, the movement of living organisms across continents during international trade represents a serious threat to ecosystems and biosecurity measures should be taken at a global level.
  • 3.0K
  • 19 Jan 2021
Topic Review
Plasticity
In physics and materials science, plasticity, also known as plastic deformation, is the ability of a solid material to undergo permanent deformation, a non-reversible change of shape in response to applied forces. For example, a solid piece of metal being bent or pounded into a new shape displays plasticity as permanent changes occur within the material itself. In engineering, the transition from elastic behavior to plastic behavior is known as yielding. Plastic deformation is observed in most materials, particularly metals, soils, rocks, concrete, and foams. However, the physical mechanisms that cause plastic deformation can vary widely. At a crystalline scale, plasticity in metals is usually a consequence of dislocations. Such defects are relatively rare in most crystalline materials, but are numerous in some and part of their crystal structure; in such cases, plastic crystallinity can result. In brittle materials such as rock, concrete and bone, plasticity is caused predominantly by slip at microcracks. In cellular materials such as liquid foams or biological tissues, plasticity is mainly a consequence of bubble or cell rearrangements, notably T1 processes. For many ductile metals, tensile loading applied to a sample will cause it to behave in an elastic manner. Each increment of load is accompanied by a proportional increment in extension. When the load is removed, the piece returns to its original size. However, once the load exceeds a threshold – the yield strength – the extension increases more rapidly than in the elastic region; now when the load is removed, some degree of extension will remain. Elastic deformation, however, is an approximation and its quality depends on the time frame considered and loading speed. If, as indicated in the graph opposite, the deformation includes elastic deformation, it is also often referred to as "elasto-plastic deformation" or "elastic-plastic deformation". Perfect plasticity is a property of materials to undergo irreversible deformation without any increase in stresses or loads. Plastic materials that have been hardened by prior deformation, such as cold forming, may need increasingly higher stresses to deform further. Generally, plastic deformation is also dependent on the deformation speed, i.e. higher stresses usually have to be applied to increase the rate of deformation. Such materials are said to deform visco-plastically.
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  • 10 Nov 2022
Topic Review
Meat Analogue
A meat analogue is a food industry term for a meat-like substance made from vegetarian ingredients. More common terms are plant-based meat, vegan meat, meat substitute, mock meat, meat alternative, imitation meat, or vegetarian meat, or, sometimes more pejoratively, fake meat or faux meat. Meat analogues typically approximate certain aesthetic qualities (such as texture, flavor, appearance) or chemical characteristics of specific types of meat. Many analogues are soy-based (e.g., tofu, tempeh) or gluten-based but now may also be made from pea protein. Other less common analogues include cottage cheese and mycoprotein. Because of their similarity to meats, they are frequently used in dishes and food practices similar to meat. The target market for meat analogues includes vegetarians, vegans, non-vegetarians seeking to reduce their meat consumption, and people following religious dietary laws in Hinduism, Judaism, Islam, Christian vegetarianism, and Buddhism. Increasingly, the global demand for sustainable diets in response to the outsized role animal products play in global warming and other environmental impacts has seen an increase in industries focused on finding substitutes similar to meat. However, the motivation for seeking out mock meats tends to vary depending on consumer group. The market for meat alternatives is highly dependent on "meat-reducers" — a consumer group who is primarily motivated by health consciousness and weight management. Consumers who identify as vegan, vegetarian or pescetarian are more likely to endorse concerns regarding animal welfare and/or environmentalism as primary motivators. Meat substitution has a long history. Tofu, a popular meat analogue made from soybeans, was known in China during the period of the Western Han dynasty (206 BCE – 9 CE). A document written by Tao Gu (903–970) describes how tofu was called "small mutton" and valued as an imitation meat. Meat analogues such as tofu and wheat gluten are associated with Buddhist cuisine in China and other parts of East Asia. In Medieval Europe, meat analogues were popular during the Christian observance of Lent, when the consumption of meat from warm-blooded animals is forbidden. In the 2010s, owing to concern over global warming, demand for meat from a growing middle class, and major investments by companies such as Beyond Meat and Impossible Foods, there was an increase in awareness and the market size for meat analogues in Western and Westernized markets.
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  • 24 Oct 2022
Topic Review
Transient Execution CPU Vulnerability
Transient execution CPU vulnerabilities are vulnerabilities in a computer system in which a speculative execution optimization implemented in a microprocessor is exploited to leak secret data to an unauthorized party. The classic example is Spectre that gave its name to this kind of side-channel attack, but since January 2018 many different vulnerabilities have been identified.
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  • 14 Nov 2022
Topic Review
LiDAR-Derived DEM in Flood Applications
Flood occurrence is increasing due to escalated urbanization and extreme climate change; hence, various studies on this issue and methods of flood monitoring and mapping are also increasing to reduce the severe impacts of flood disasters. The advancement of current technologies such as light detection and ranging (LiDAR) systems facilitated and improved flood applications. Since the conventional methods cannot produce high-resolution digital elevation model (DEM) data, which results in low accuracy of flood simulation results, LiDAR data are extensively used as an alternative. This review aims to study the potential and the applications relevant to flood studies from a LiDAR-derived DEM perspective. It also provides insight into the operating principles of different LiDAR systems, system components, and advantages and disadvantages of each system. Furthermore, the challenges and future perspectives regarding DEM LiDAR data for flood mapping and assessment are also discussed. This study demonstrates that LiDAR-derived data are useful in flood risk management, especially in the future assessment of flood-related problems.  
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  • 04 Aug 2020
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