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Topic Review
Megafaunal Wolf
The megafaunal wolf (Canis cf. lupus) was a Late Pleistocene – early Holocene hypercarnivore similar in size to a large extant gray wolf. It had a shorter, broader palate with large carnassial teeth relative to its overall skull size. This adaptation allowed it to prey and scavenge on Pleistocene megafauna. Such an adaptation is an example of phenotypic plasticity. It was once distributed across the northern Holarctic.
  • 4.7K
  • 23 Nov 2022
Topic Review
Burnside-Butler Syndrome Genotype-Phenotype Associations
The 15q11.2 BP1-BP2 deletion (Burnside-Butler) syndrome is emerging as the most common cytogenetic finding in patients with neurodevelopmental or autism spectrum disorders (ASD) presenting for microarray genetic testing. Clinical findings in Burnside-Butler syndrome include developmental and motor delays, congenital abnormalities, learning and behavioral problems, and abnormal brain findings. To better define symptom presentation, we performed comprehensive cognitive and behavioral testing, collected medical and family histories, and conducted clinical genetic evaluations. The 15q11.2 BP1-BP2 region includes the TUBGCP5, CYFIP1, NIPA1, and NIPA2 genes. To determine if additional genomic variation outside of the 15q11.2 region influences expression of symptoms in Burnside-Butler syndrome, whole-exome sequencing was performed on the parents and affected children for the first time in five families with at least one parent and child with the 15q1l.2 BP1-BP2 deletion. In total, there were 453 genes with possibly damaging variants identified across all of the affected children. Of these, 99 genes had exclusively de novo variants and 107 had variants inherited exclusively from the parent without the deletion. There were three genes (APBB1, GOLGA2, and MEOX1) with de novo variants that encode proteins evidenced to interact with CYFIP1. In addition, one other gene of interest (FAT3) had variants inherited from the parent without the deletion and encoded a protein interacting with CYFIP1. The affected individuals commonly displayed a neurodevelopmental phenotype including ASD, speech delay, abnormal reflexes, and coordination issues along with craniofacial findings and orthopedic-related connective tissue problems. Of the 453 genes with variants, 35 were associated with ASD. On average, each affected child had variants in 6 distinct ASD-associated genes (x¯ = 6.33, sd = 3.01). In addition, 32 genes with variants were included on clinical testing panels from Clinical Laboratory Improvement Amendments (CLIA) approved and accredited commercial laboratories reflecting other observed phenotypes. Notably, the dataset analyzed in this study was small and reported results will require validation in larger samples as well as functional follow-up. Regardless, we anticipate that results from our study will inform future research into the genetic factors influencing diverse symptoms in patients with Burnside-Butler syndrome, an emerging disorder with a neurodevelopmental behavioral phenotype.
  • 4.7K
  • 25 Mar 2021
Topic Review
Toxicity of Titanium Compounds
Titanium and its compounds are broadly used in both industrial and domestic products, including jet engines, missiles, prostheses, implants, pigments, cosmetics, food, and photocatalysts for environmental purification and solar energy conversion. Although titanium/titania-containing materials are usually safe for human, animals and environment, increasing concerns on their negative impacts have been postulated. We have reported the state of knowledge about toxicity of titanium, its alloys and oxides. Due to the alarming increase in titania/titanium applications in various daily care products and medical treatment (e.g. dental implants) the possible toxicity and environmental impact should be considered.  The collected data might allow to identify some harms associated with using of titania and titanium compounds.
  • 4.7K
  • 21 Feb 2021
Topic Review
Hegemony
Hegemony (UK: /hɪˈɡɛməni, hɪˈdʒɛməni/, US: /hɪˈdʒɛməni/ (pronunciation (help·info)) or /ˈhɛdʒəˌmoʊni/) is the political, economic, or military predominance or control of one state over others. In Ancient Greece (8th century BC – 6th century AD), hegemony denoted the politico-military dominance of a city-state over other city-states. The dominant state is known as the hegemon. In the 19th century, hegemony came to denote the "Social or cultural predominance or ascendancy; predominance by one group within a society or milieu". Later, it could be used to mean "a group or regime which exerts undue influence within a society". Also, it could be used for the geopolitical and the cultural predominance of one country over others, from which was derived hegemonism, as in the idea that the Great Powers meant to establish European hegemony over Africa, Asia and Latin America. In cultural imperialism, the leader state dictates the internal politics and the societal character of the subordinate states that constitute the hegemonic sphere of influence, either by an internal, sponsored government or by an external, installed government. In international relations theory, hegemony denotes a situation of (i) great material asymmetry in favour of one state, that has (ii) enough military power to systematically defeat any potential contester in the system, (iii) controls the access to raw materials, natural resources, capital and markets, (iv) has competitive advantages in the production of value added goods, (v) generates an accepted ideology reflecting this status quo; and (vi) is functionally differentiated from other states in the system, being expected to provide certain public goods such as security, or commercial and financial stability. The Marxist theory of cultural hegemony, associated particularly with Antonio Gramsci, is the idea that the ruling class can manipulate the value system and mores of a society, so that their view becomes the world view (Weltanschauung): in Terry Eagleton's words, "Gramsci normally uses the word hegemony to mean the ways in which a governing power wins consent to its rule from those it subjugates". In contrast to authoritarian rule, cultural hegemony "is hegemonic only if those affected by it also consent to and struggle over its common sense".
  • 4.7K
  • 10 Nov 2022
Topic Review
Stilbene Biosynthesis
Stilbenes are a small family of polyphenolic secondary metabolites that can be found in several distantly related plant species. These compounds act as phytoalexins, playing a crucial role in plant defense against phytopathogens, as well as being involved in the adaptation of plants to abiotic environmental factors. Among stilbenes, trans-resveratrol is certainly the most popular and extensively studied for its health properties. However, many other stilbenes, both monomeric and oligomeric, are currently under intensive investigation due to their biological role and bioactivity.
  • 4.7K
  • 14 Jan 2021
Topic Review
Problems Associated with Plant Micropropagation
The production of micropropagated plants in plant-tissue-culture laboratories and nurseries is the most important method for propagation of many economic plants. Micropropagation based on tissue-culture technology involves large-scale propagation, as it allows multiplication of a huge number of true-to-type propagules in a very short time and in a very limited space, as well as all year round, regardless of the climate.
  • 4.7K
  • 04 Aug 2022
Topic Review
Hydrothermal Liquefaction of Biomass
Hydrothermal liquefaction is a high-temperature high-pressure thermochemical conversion method adapted to convert high-water content biomass feedstocks to biofuels and many other valuable industrial chemicals. The hydrothermal process is broadly classified into carbonization, liquefaction, and gasification with hydrothermal liquefaction conducted in the intermediate temperature range of 250–374 °C and pressure of 4–25 MPa. Over the years, various solvents and co-solvents have been used as conversion mediums to promote easy decomposition of the lignocellulosic components in biomass. To obtain the final products, the product separation process typically involves multiple extraction and evaporation steps, which greatly depend on the type of extractive solvents and process parameters. In general, the main aim of the hydrothermal process is to produce a primary product, such as bio-oil, biochar, gases, or industrial chemicals, such as adhesives, benzene, toluene, and xylene.
  • 4.7K
  • 19 Aug 2021
Topic Review
Platypus
The platypus (Ornithorhynchus anatinus), sometimes referred to as the duck-billed platypus, is a semiaquatic, egg-laying mammal endemic to eastern Australia, including Tasmania. The platypus is the sole living representative or monotypic taxon of its family (Ornithorhynchidae) and genus (Ornithorhynchus), though a number of related species appear in the fossil record. Together with the four species of echidna, it is one of the five extant species of monotremes, mammals that lay eggs instead of giving birth to live young. Like other monotremes, it senses prey through electrolocation. It is one of the few species of venomous mammals, as the male platypus has a spur on the hind foot that delivers a venom, capable of causing severe pain to humans. The unusual appearance of this egg-laying, duck-billed, beaver-tailed, otter-footed mammal baffled European naturalists when they first encountered it, and the first scientists to examine a preserved platypus body (in 1799) judged it a fake, made of several animals sewn together. The unique features of the platypus make it an important subject in the study of evolutionary biology, and a recognisable and iconic symbol of Australia . It is culturally significant to several Aboriginal peoples of Australia, who also used to hunt the animal for food. It has appeared as a mascot at national events and features on the reverse of the Australian twenty-cent coin, and the platypus is the animal emblem of the state of New South Wales. Until the early 20th century, humans hunted the platypus for its fur, but it is now protected throughout its range. Although captive-breeding programs have had only limited success, and the platypus is vulnerable to the effects of pollution, it is not under any immediate threat. (As of 2020), the platypus is a legally protected species in all states where it occurs. It is listed as an endangered species in South Australia and Victoria and has been recommended for listing in New South Wales. The species is classified as a near-threatened species by the IUCN, but a November 2020 report has recommended that it is upgraded to threatened species under the federal EPBC Act, due to habitat destruction and declining numbers in all states.
  • 4.7K
  • 18 Nov 2022
Topic Review Peer Reviewed
Road Markings and Signs in Road Safety
Due to the dynamic nature and complexity of road traffic, road safety is one of the most demanding social challenges. Therefore, contemporary road safety strategies incorporate a multidisciplinary and comprehensive approaches to address this problem and improve the safety of each individual element, i.e., the human, vehicle, and road. Traffic control devices are an important part of road infrastructure, among which road markings and road signs play a significant role. In general, road markings and signs represent basic means of communication between the road authorities and road users and, as such, provide road users with necessary information about the rules, warnings, obligations, and other information related to the upcoming situations and road alignment. The aim of this entry is to briefly present the main functions and characteristics of road markings and signs, and their role in road safety. In addition, practical issues and future trends and directions regarding road markings and signs are discussed. 
  • 4.7K
  • 21 Oct 2022
Topic Review
Gallium Nitride High-Electron-Mobility Transistor
In recent years, GaN-based devices have been widely used in a variety of application fields. GaN-based high-electron-mobility transistors (HEMTs) are superior to conventional silicon (Si) based devices in terms of switching frequency, power rating, thermal capability and efficiency, which are crucial factors to enhance the performances of advanced power converters. This paper addresses some fundamental issues concerning intrinsic features of GaN material and key technology in practical application of GaN-based power switching devices.
  • 4.7K
  • 30 Jul 2020
Topic Review
Reindeer Distribution
The reindeer is a widespread and numerous species in the northern Holarctic, being present in both tundra and taiga (boreal forest). Originally, the reindeer was found in Scandinavia, eastern Europe, Russia , Mongolia, and northern China north of the 50th latitude. In North America, it was found in Canada , Alaska (United States ), and the northern contiguous USA from Washington to Maine. In the 19th century, it was apparently still present in southern Idaho. It also occurred naturally on Sakhalin, Greenland, and probably even in historical times in Ireland. During the late Pleistocene era, reindeer were found further south, such as at Nevada, Tennessee , and Alabama in North America and Spain in Europe. Today, wild reindeer have disappeared from many areas within this large historical range, especially from the southern parts, where it vanished almost everywhere. Populations of wild reindeer are still found in Norway , Finland , Siberia, Greenland, Alaska, and Canada . Domesticated reindeer are mostly found in northern Fennoscandia and Russia, with a herd of approximately 150–170 semi-domesticated reindeer living around the Cairngorms region in Scotland. The last remaining wild tundra reindeer in Europe are found in portions of southern Norway . A few reindeer from Norway were introduced to the South Atlantic island of South Georgia in the beginning of the 20th century. The South Georgian reindeer totaled some estimated 2600 animals in two distinct herds separated by glaciers. Although the flag and the coat of arms of the territory contain an image of a reindeer, they were eradicated from 2013 to 2017 because of the environmental damage they caused. Around 4000 reindeer have been introduced into the French sub-Antarctic archipelago of Kerguelen Islands. East Iceland has a small herd of about 2500–3000 animals. Caribou and reindeer numbers have fluctuated historically, but many herds are in decline across their range. This global decline is linked to climate change for northern, migratory caribou and reindeer herds and industrial disturbance of caribou habitat for sedentary, non-migratory herds.
  • 4.7K
  • 28 Nov 2022
Topic Review
PC5-Based Cellular-V2X Evolution and Deployment
C-V2X (Cellular Vehicle-to-Everything) is a state-of-the-art wireless technology used in autonomous driving and intelligent transportation systems (ITS). 
  • 4.7K
  • 19 Feb 2021
Topic Review
Theories of the Metaphor
Metaphors are an integral and important part of human communication and greatly impact the way our thinking is formed and how we understand the world. The theory of the conceptual metaphor has shifted the focus of research from words to thinking, and also influenced research of the linguistic metaphor, which deals with the issue of how metaphors are expressed in language or speech.
  • 4.7K
  • 12 Jun 2023
Topic Review
1G and 2G Bioethanol Production
First-generation (1G) bioethanol is one of the most used liquid biofuels in the transport industry. It is generated by using sugar- or starch-based feedstocks, while second-generation (2G) bioethanol is generated by using lignocellulosic feedstocks. Distillers’ dried grains with solubles (DDGS) is a byproduct of first-generation bioethanol production with a current annual production of 22.6 million tons in the USA. DDGS is rich in fiber and valuable nutrients contents, which can be used to produce lignocellulolytic enzymes such as cellulases and hemicellulases for 2G bioethanol production.
  • 4.7K
  • 26 Dec 2022
Topic Review
Developmental Psychology
Developmental psychology is the scientific study of how and why human beings change over the course of their life. Originally concerned with infants and children, the field has expanded to include adolescence, adult development, aging, and the entire lifespan. Developmental psychologists aim to explain how thinking, feeling, and behaviors change throughout life. This field examines change across three major dimensions: physical development, cognitive development, and social emotional development. Within these three dimensions are a broad range of topics including motor skills, executive functions, moral understanding, language acquisition, social change, personality, emotional development, self-concept, and identity formation. Developmental psychology examines the influences of nature and nurture on the process of human development, and processes of change in context across time. Many researchers are interested in the interactions among personal characteristics, the individual's behavior, and environmental factors, including the social context and the built environment. Ongoing debates in regards to developmental psychology include biological essentialism vs. neuroplasticity and stages of development vs. dynamic systems of development. Developmental psychology involves a range of fields, such as educational psychology, child psychopathology, forensic developmental psychology, child development, cognitive psychology, ecological psychology, and cultural psychology. Influential developmental psychologists from the 20th century include Urie Bronfenbrenner, Erik Erikson, Sigmund Freud, Jean Piaget, Barbara Rogoff, Esther Thelen, and Lev Vygotsky.
  • 4.7K
  • 30 Oct 2022
Topic Review
Tumoroid
The term “tumoroid” means “tumor-like organoid”: tumoroids typically derive from primary tumors harvested from oncological patients and they can mimic human tumor microenvironment (TME); nowadays, they are considered a promising tool for cost-effective studies on novel anticancer drugs to be used in precision medicine in the field of oncology.
  • 4.7K
  • 18 Jun 2024
Topic Review
Around the World Sailing Record
The first around the world sailing record for circumnavigation of the world was Juan Sebastián Elcano and the remaining members of Ferdinand Magellan's crew who completed their journey in 1522. The first solo record was set by Joshua Slocum in the Spray (1898). The current record holders are IDEC 3, skippered by Francis Joyon in 40 days, 23 hours, 30 minutes and 30 seconds for a crewed journey, and François Gabart with Macif in 42 days, 16 hours, 40 minutes and 35 seconds for a solo journey. Most races or solo attempts start from Europe. Due to the configuration of the continents, sailing around the world consists of sailing on the Southern Ocean around the Antarctica continent, passing south of Cape Horn, Cape of Good Hope and Cape Leeuwin. Since 1918 the Panama Canal is an option but the locks must be entered and exited using engine power. Large stretches of the canal can be crossed under sail power. Sailing around the world can be done by two directions: eastward or westward. The dominant winds and currents (outside tropical areas) make the voyage eastwards on the Southern hemisphere faster, most skippers and yachts who race prefer this route. Today, the multihulls perform much better than monohulls and hold the best times. Leisure yacht skippers who prefer tropical seas more often go westward, using the trade winds (and the Panama canal). The Jules Verne Trophy is awarded to the skipper who breaks the previous Jules Verne record, starting from an imaginary line between the Créac'h lighthouse on Ouessant (Ushant) Island, France , and the Lizard Lighthouse, United Kingdom . This has not always been the OUTRIGHT record. The records are homologated by the World Sailing Speed Record Council (WSSRC). According to the WSSRC, for around the world sailing records, there is a rule saying that the length must be at least 21,600 nmi calculated along the shortest possible track from the starting port and back that does not cross land and does not go below 63°S. The great-circle distance formulas are to be used, assuming that the great circle length is 21,600 nmi. It is allowed to have one single waypoint to lengthen the calculated track. The equator must be crossed. In reality, this means that the boat should pass a waypoint at or not far from the antipode of the starting port of the journey (the exact position depends on how short the shortest possible track is). For example, the Vendée Globe starts at 46°N 2°W, has a waypoint at 57°S 180°E, and barely makes the distance requirement. The participants don't have to go to the antipode at 46°S 178°E since the rounding of Africa gives extra distance.
  • 4.7K
  • 11 Nov 2022
Topic Review
Barrier Layer of Cu Interconnects
The barrier layer in Cu technology is essential to prevent Cu from diffusing into the dielectric layer at high temperatures; therefore, it must have a high stability and good adhesion to both Cu and the dielectric layer. In the past three decades, tantalum/tantalum nitride (Ta/TaN) has been widely used as an inter-layer to separate the dielectric layer and the Cu. However, to fulfill the demand for continuous down-scaling of the Cu technology node, traditional materials and technical processes are being challenged. Direct electrochemical deposition of Cu on top of Ta/TaN is not realistic, due to its high resistivity. Therefore, pre-deposition of a Cu seed layer by physical vapor deposition (PVD) or chemical vapor deposition (CVD) is necessary, but the non-uniformity of the Cu seed layer has a devastating effect on the defect-free fill of modern sub-20 or even sub-10 nm Cu technology nodes. New Cu diffusion barrier materials having ultra-thin size, high resistivity and stability are needed for the successful super-fill of trenches at the nanometer scale. In this review, we briefly summarize recent advances in the development of Cu diffusion-proof materials, including metals, metal alloys, self-assembled molecular layers (SAMs), two-dimensional (2D) materials and high-entropy alloys (HEAs). Also, challenges are highlighted and future research directions are suggested.
  • 4.7K
  • 30 Jul 2021
Topic Review
Six-Gear Roadmap towards Smart Factory
The fourth industrial revolution is the transformation of manufacturing into smart manufacturing. Advanced industrial digital technologies that make the trend Industry 4.0 are considered as the transforming force that will enable this transformation. However, these technologies need to be connected, integrated and used effectively to create value and to provide insights for data driven manufacturing. Smart manufacturing is a journey and requires a roadmap to guide manufacturing organizations for its adoption. The proposed roadmap is a simple holistic management strategy for an Industry 4.0 implementation journey. It serves as a strategic practical tool for rapid adoption of Industry 4.0 technologies. It bridges the gap between the advanced technologies and their application in manufacturing industry, especially for SMEs.
  • 4.7K
  • 06 Aug 2021
Topic Review
Mesoamerican Genetic Studies
Mesoamerica is a historically and culturally defined geographic area comprising current central and south Mexico, Belize, Guatemala, El Salvador, and border regions of Honduras, western Nicaragua, and northwestern Costa Rica. The permanent settling of Mesoamerica was accompanied by the development of agriculture and pottery manufacturing (2500 BCE–150 CE), which led to the rise of several cultures connected by commerce and farming. Hence, Mesoamericans probably carried an invaluable genetic diversity partly lost during the Spanish conquest and the subsequent colonial period. Mesoamerican ancient DNA (aDNA) research has mainly focused on the study of mitochondrial DNA in the Basin of Mexico and the Yucatán Peninsula and its nearby territories, particularly during the Postclassic period (900–1519 CE). 
  • 4.7K
  • 24 Nov 2020
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