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Topic Review
Marine Mammal
Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They do not represent a distinct taxon or systematic grouping, but rather have a polyphyletic relation due to convergent evolution, as in they do not have an immediate common ancestor. They are also unified by their reliance on the marine environment for feeding. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water, but need to return to land for important activities such as mating, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. Their diet varies considerably as well; some may eat zooplankton, others may eat fish, squid, shellfish, sea-grass and a few may eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. Marine mammals were first hunted by aboriginal peoples for food and other resources. Many were also the target for commercial industry, leading to a sharp decline in all populations of exploited species, such as whales and seals. Commercial hunting lead to the extinction of †Steller's sea cow, †sea mink, †Japanese sea lion and the †Caribbean monk seal. After commercial hunting ended, some species, such as the gray whale and northern elephant seal, have rebounded in numbers; conversely, other species, such as the North Atlantic right whale, are critically endangered. Other than hunting, marine mammals can be killed as bycatch from fisheries, where they become entangled in fixed netting and drown or starve. Increased ocean traffic causes collisions between fast ocean vessels and large marine mammals. Habitat degradation also threatens marine mammals and their ability to find and catch food. Noise pollution, for example, may adversely affect echolocating mammals, and the ongoing effects of global warming degrade arctic environments.
  • 3.9K
  • 21 Oct 2022
Topic Review
Pinus
The pine (Pinus L.) is the largest and most heteromorphic plant genus of the pine family (Pinaceae Lindl. ), which grows almost exclusively in the northern hemisphere. The demand for plant-based remedies, supplements and functional food is growing worldwide.
  • 3.9K
  • 17 Jan 2022
Topic Review
Characterization of MXene's Terminations
MXene, 2D transition metal carbides, nitrides, and carbonitrides with a unique 2D structure, inspired a series of function applications related to energy storage and conversion, biometrics and sensing, lighting, purification, and separation. Its surface terminations are confined by the adjacent MXene layers, and form the 2D planar space with symmetrical surfaces, which is similar to a 2D nanoreactor that can be utilized and determined MXene’s function. Accurate characterization of MXene surface terminations is the prerequisite for studying the regulatory methods and the influence of properties and performance. Because the surface termination of MXene presents two-dimensional plane distribution and the collision probability of atoms, molecules, electrons, and optical signals is low. MXene prepared by chemical methods has certain impurity content. In addition, most surface terminations do not exist in a stable state, which leads to the difficulty of the accurate characterization of MXene surface terminations. At present, XPS, EDX, XAS and EELS are often used for qualitative and quantitative analysis of MXene surface terminations.
  • 3.9K
  • 09 Nov 2022
Topic Review Peer Reviewed
Aircraft Icing Severity Evaluation
Aircraft icing refers to the ice buildup on the surface of an aircraft flying in icing conditions. The ice accretion on the aircraft alters the original aerodynamic configuration and degrades the aerodynamic performances and may lead to unsafe flight conditions. Evaluating the flow structure, icing mechanism and consequences is of great importance to the development of an anti/deicing technique. Studies have shown computational fluid dynamics (CFD) and machine learning (ML) to be effective in predicting the ice shape and icing severity under different flight conditions. CFD solves a set of partial differential equations to obtain the air flow fields, water droplets trajectories and ice shape. ML is a branch of artificial intelligence and, based on the data, the self-improved computer algorithms can be effective in finding the nonlinear mapping relationship between the input flight conditions and the output aircraft icing severity features.
  • 3.9K
  • 13 Apr 2022
Topic Review
Mirroring (Psychology)
User:RMCD bot/subject notice Mirroring is the behavior in which one person unconsciously imitates the gesture, speech pattern, or attitude of another. Mirroring often occurs in social situations, particularly in the company of close friends or family. The concept often affects other individuals' notions about the individual that is exhibiting mirroring behaviors, which can lead to the individual building rapport with others. Mirroring is the subconscious replication of another person's nonverbal signals. This concept takes place in everyday interactions and often goes unnoticed by both the person enacting the mirroring behaviors as well as the individual who is being mirrored. The activation of mirror neurons takes place within the individual who begins to mirror another's movements and allows them a greater connection and understanding with the individual who they are mirroring, as well as allowing the individual who is being mirrored to feel a stronger connection with the other individual. Mirroring is distinct from conscious imitation under the premise that while the latter is a conscious, typically overt effort to copy another person, mirroring is unconsciously done during the act and often goes unnoticed. The display of mirroring often begins as early as infancy, as babies begin to mimic individuals around them and establish connections with particular body movements. The ability to mimic another person's actions allows the infant to establish a sense of empathy and thus begin to understand another person's emotions. The infant continues to establish connections with other individual's emotions and subsequently mirror their movements. Mirroring can establish rapport with the individual who is being mirrored, as the similarities in nonverbal gestures allow the individual to feel more connected with the person exhibiting the mirrored behavior. As the two individuals in the situation display similar nonverbal gestures, they may believe that they share similar attitudes and ideas as well. Mirror neurons react to and cause these movements, allowing the individuals to feel a greater sense of engagement and belonging within the situation.
  • 3.9K
  • 06 Oct 2022
Topic Review
Kangxi Radical
The 214 Kangxi radicals (Chinese: 康熙部首; pinyin: Kāngxī bùshǒu), also known as the Zihui radicals, form a system of radicals (部首) of Chinese characters. The radicals are numbered in stroke count order. They are the most popular system of radicals for dictionaries that order Traditional Chinese characters (hanzi, hanja, kanji, chữ hán) by radical and stroke count. They are officially part of the Unicode encoding system for CJKV characters, in their standard order, under the coding block "Kangxi radicals", while their graphic variants are contained in the "CJK Radicals Supplement". Thus, a reference to "radical 61", for example, without additional context, refers to the 61st radical of the Kangxi Dictionary, 心; xīn "heart". Originally introduced in the 1615 Zihui (字彙), they are more commonly named in relation to the Kangxi Dictionary of 1716 (Kāngxī 康熙 being the era name for 1662–1723). The 1915 encyclopedic word dictionary Ciyuan (辭源) also uses this system. In modern times, many dictionaries that list Traditional Chinese head characters continue to use this system. For example, the Wang Li Character Dictionary of Ancient Chinese (王力古漢語字典, 2000) adopted the Kangxi radicals system. The system of 214 Kangxi radicals is based on the older system of 540 radicals used in the Han-era Shuowen Jiezi. Since 2009, the PRC government has promoted a 201-radical system (Table of Han Character Radicals, 汉字部首表) as a national standard for Simplified Chinese (see list of Xinhua Zidian radicals).
  • 3.9K
  • 22 Nov 2022
Topic Review
Inner Core
The Earth's inner core is the Earth's innermost part. It is primarily a solid ball with a radius of about 1,220 kilometres (760 miles), which is about 70% of the Moon's radius. It is composed of an iron–nickel alloy and some other elements. The temperature at the inner core's surface is approximately 5,700 K (5,430 °C) or 9806 °F, which is about the temperature at the surface of the Sun.
  • 3.9K
  • 10 Nov 2022
Topic Review
Visual Basic
User:RMCD bot/subject notice Visual Basic (also referred to as Classic Visual Basic) is a third-generation event-driven programming language from Microsoft known for its Component Object Model (COM) programming model first released in 1991 and declared legacy during 2008. Microsoft intended Visual Basic to be relatively easy to learn and use. Visual Basic was derived from BASIC and enables the rapid application development (RAD) of graphical user interface (GUI) applications, access to databases using Data Access Objects, Remote Data Objects, or ActiveX Data Objects, and creation of ActiveX controls and objects. A programmer can create an application using the components provided by the Visual Basic program itself. Over time the community of programmers developed third-party components. Programs written in Visual Basic can also make use of the Windows API, which requires external functions declarations. The final release was version 6 in 1998 (now known simply as Visual Basic). On April 8, 2008, Microsoft stopped supporting Visual Basic 6.0 IDE. The Microsoft Visual Basic team still maintains compatibility for Visual Basic 6.0 applications through its "It Just Works" program on supported Windows operating systems. In 2014, some software developers still preferred Visual Basic 6.0 over its successor, Visual Basic .NET. In 2014 some developers lobbied for a new version of the VB6 programming environment. In 2016, Visual Basic 6.0 won the technical impact award at The 19th Annual D.I.C.E. Awards. Visual Basic 6.0 was selected as the most dreaded programming language by respondents of Stack Overflow's annual developer survey in 2016, 2017, and 2018. A dialect of Visual Basic, Visual Basic for Applications (VBA), is used as a macro or scripting language within several Microsoft and ISV applications, including Microsoft Office.
  • 3.9K
  • 17 Nov 2022
Topic Review
Cold Atmospheric Pressure Plasma Technology
Cold atmospheric pressure plasma (CAPP) technology has received substantial attention due to its valuable properties including operational simplicity, low running cost, and environmental friendliness. Several different gases (air, nitrogen, helium, argon) and techniques (corona discharge, dielectric barrier discharge, plasma jet) can be used to generate plasma at atmospheric pressure and low temperature. Plasma treatment is routinely used in materials science to modify the surface properties (e.g., wettability, chemical composition, adhesion) of a wide range of materials (e.g., polymers, textiles, metals, glasses). Moreover, CAPP seems to be a powerful tool for the inactivation of various pathogens (e.g., bacteria, fungi, viruses) in the food industry (e.g., food and packing material decontamination, shelf life extension), agriculture (e.g., disinfection of seeds, fertilizer, water, soil) and medicine (e.g., sterilization of medical equipment, implants). Plasma medicine also holds great promise for direct therapeutic treatments in dentistry (tooth bleaching), dermatology (atopic eczema, wound healing) and oncology (melanoma, glioblastoma).
  • 3.9K
  • 10 Jun 2021
Topic Review
Fused 1,5-naphthyridines
Heterocyclic nitrogen compounds, including fused 1,5-naphthyridines, have versatile applications in synthetic organic chemistry and play an important role in the field of medicinal chemistry, as many of them have a wide range of biological activities. In this review, a wide range of synthetic protocols for the construction of this scaffold are presented. For example, Friedländer, Skraup, Semmlere-Wolff, and hetero-Diels-Alder, among others, are well known classical synthetic protocols used for the construction of the main 1,5-naphthyridine scaffold. These syntheses are classified according to the nature of the cycle fused to the 1,5-naphthyridine ring: carbocycles, nitrogen heterocycles, oxygen heterocycles, and sulphur heterocycles. In addition, taking into account the aforementioned versatility of these heterocycles, their reactivity is presented as well as their use as a ligand for metal complexes formation. Finally, those fused 1,5-naphthyridines that present biological activity and optical applications, among others, are indicated.
  • 3.9K
  • 31 Aug 2020
Topic Review
Critical Minerals
Critical minerals are paramount to the successful deployment of low-carbon technologies in future transportation, defense, agriculture, healthcare, and infrastructure. They have a significant economic importance and their insecure supplies may hinder the development and industrial application of new technologies. An implementation of large quantities of minerals, in particular metals, into the clean energy transition will create new economic opportunities but also bring new challenges to energy security that could lead to unexpected dependencies on raw materials.
  • 3.9K
  • 30 Aug 2022
Topic Review Peer Reviewed
SEM-PLS Approach to Green Building
Green buildings refer to buildings that decrease adverse environmental effects and maintain natural resources. They can diminish energy consumption, greenhouse gas emissions, the usage of non-renewable materials, water consumption, and waste generation while improving occupants’ health and well-being. As such, several rating tools and benchmarks have been developed worldwide to assess green building performance (GBP), including the Building Research Establishment Environmental Assessment Method (BREEAM) in the United Kingdom, German Sustainable Building Council (DGNB), Leadership in Energy and Environmental Design (LEED) in the United States and Canada, Comprehensive Assessment System for Built Environment Efficiency (CASBEE) in Japan, Green Star in Australia, Green Mark in Singapore, and Green Building Index in Malaysia. Energy management (EM) during building operation could also improve GBP. One of the best approaches to evaluating the impact of EM on GBP is by using structural equation modelling (SEM). SEM is a commanding statistical method to model testing. One of the most used SEM variance-based approaches is partial least squares (PLS), which can be implemented in the SmartPLS application. PLS-SEM uses path coefficients to determine the strength and significance of the hypothesised relationships between the latent constructs. 
  • 3.9K
  • 13 Apr 2022
Topic Review
Roof Plate in Neural Development
The roof plate is the most dorsal region of the neural tube. The Roof plate serves as an organizing center that controls proliferation and differentiation of dorsal interneurons. In addition, this region is involved in development of neural crest cells, which are the source of migratory neural crest cells. During early development of the spinal cord, roof plate cells secrete signaling molecules, such as Wnt and BMP family proteins, which regulate development of neural crest cells and dorsal spinal cord. After the dorso-ventral pattern is established, spinal cord dynamically changes its morphology. With this morphological transformation, the lumen of the spinal cord gradually shrinks to form the central canal. Accompanied by formation of the central canal, roof plate cells dramatically stretch along the dorso-ventral axis. During this stretching process, the tips of roof plate cells maintain contact with cells surrounding the shrinking lumen of the spinal cord, eventually exposed to the inner surface of the central canal. In this late stage of the spinal cord development, Wnt secreted by stretched roof plate cells regulates transformation of roof plate cells themselves and promotes proliferation of ependymal cells surrounding the central canal, including neural progenitor cells, in the spinal cord.
  • 3.9K
  • 05 Aug 2021
Topic Review
Defect-Related Etch Pits on Crystals and Their Utilization
Etch pits could form on an exposed surface of a crystal when the crystal is exposed to an etching environment or chemicals. Due to different dissolution rates along various crystalline directions in a crystal, the dissolution process is anisotropic; hence, etch pits usually have a regular shape. The morphology, size, and density of etch pits can be affected by various factors, including the chemical composition of the etchant, etching time, etching temperature, status of the matrix, and so on. Traditionally, etch pits are utilized to evaluate the dislocation density and some defect-related properties. Now, in the modern fabrication industries, the relationship between etch pits and defects has been utilized more skillfully. High-quality crystals can be fabricated by controlling dislocations revealed by etch pits. Meanwhile, with the as-revealed dislocation as the diffusion path of atoms, new crystals will emerge in corresponding etch pits.
  • 3.9K
  • 11 Nov 2022
Topic Review
Intra-Articular Administration of Therapeutics for Joint Disorders
Several acute and chronic inflammatory diseases of the joints affect individuals. Intra-articular (IA) drug delivery is often preferred when the joint disease is severe and painful since it places high concentrations of the drug directly at the desired site. Researchers have reported different strategies for increasing the local retention of the intra-articularly administered medication. 
  • 3.9K
  • 23 Nov 2022
Topic Review
Cyc
Cyc (pronounced /ˈsaɪk/ SYKE) is a long-term artificial intelligence project that aims to assemble a comprehensive ontology and knowledge base that spans the basic concepts and rules about how the world works. Hoping to capture common sense knowledge, Cyc focuses on implicit knowledge that other AI platforms may take for granted. This is contrasted with facts one might find somewhere on the internet or retrieve via a search engine or Wikipedia. Cyc enables semantic reasoners to perform human-like reasoning and be less "brittle" when confronted with novel situations. Douglas Lenat began the project in July 1984 at MCC, where he was Principal Scientist 1984–1994, and then, since January 1995, has been under active development by the Cycorp company, where he is the CEO.
  • 3.9K
  • 19 Oct 2022
Topic Review
Ionocraft
An ionocraft or ion-propelled aircraft (commonly known as a lifter or hexalifter) is a device that uses an electrical electrohydrodynamic (EHD) phenomenon to produce thrust in the air without requiring any combustion or moving parts. The term "ionocraft" dates back to the 1960s, an era in which EHD experiments were at their peak. In its basic form, it simply consists of two parallel conductive electrodes, one in the form of a fine wire and another which may be formed out of wire grid, tubes or foil skirts with a smooth round surface. When such an arrangement is powered by high voltage (in the range of a few kilovolts), it produces thrust. The ionocraft forms part of the EHD thruster family, but is a special case in which the ionisation and accelerating stages are combined into a single stage. The device is a popular science fair project for students. It is also popular among anti-gravity or so-called "electrogravitics" proponents, due to the research of Thomas Townsend Brown, who built these devices in the 1920s and incorrectly believed that he had found a way to modify gravity using electric fields. The term "lifter" is an accurate description because it is not an anti-gravity device; rather, it produces lift using the same basic principle as a rocket, i.e. from the equal but opposite force upward generated by the driving force downward, specifically by driving the ionized air downward in the case of the ionocraft. Much like a rocket or a jet engine (it can actually be much more thrust efficient than a jet engine), the force that an ionocraft generates is consistently oriented along its own axis, regardless of the surrounding gravitational field. Claims of the device also working in a vacuum have been disproved. Ionocraft require many safety precautions due to the high voltage required for their operation; nevertheless, a large subculture has grown up around this simple EHD thrusting device and its physics are now known to a much better extent.
  • 3.9K
  • 01 Dec 2022
Topic Review
Stereolithography
Being the earliest form of Additive manufacturing, Stereolithography (SLA) fabricates 3D objects by selectively solidifying the liquid resin through photopolymerization reaction. The ability to fabricate objects with high accuracy as well as a wide variety of materials brings much attention to stereolithography. Since its invention in 1980s, SLA underwent four generations of major technological innovation over the past 40 years. These innovations have thus result in a diversifies range of stereolithography systems with dramatically improved resolution, throughput, and materials selection for creating complex 3D objects and devices. In this paper, we review the four generations stereolithography processes, which are scanning, projection, continuous and volumetric stereolithography. For each generation, representative stereolithography system configurations are also discussed in detail. In addition, other derivative technologies, such as scanning-projection, multi-material, and magnetically assisted stereolithography processes, are also included in this review.
  • 3.9K
  • 16 Sep 2020
Topic Review
Tire Pyrolysis Oil
Energy is essential for the nature of life and the development of countries. The main demand for the 21st century is to fulfill growing energy needs. Pakistan, through the use of fossil fuels, meets energy demands. There is pressure on the economy of the country due to the massive reliance on fossil fuels, and this tendency is influenced by various environmental impacts. To overcome the burden on fossil fuels, more attention has been drawn to provide fossil fuel substitution. Tire pyrolysis is among the effective substitutes of the fuel technology that generates useful products of liquid oil, char, and pyro gas.
  • 3.9K
  • 30 Sep 2021
Topic Review
Aerogel-Based Plasters
Aerogel has entered the construction field in the last two decades as a component of many insulation products, due to its high thermal performance. Aerogel-based plasters allow the matching of high thermal performance and limited thickness. This makes them suitable when retrofitting an existing building and also when restoring a heritage building. This entry presents the state of the art of the research on aerogel-based plasters as a part of the aerogel-products for the building sector.
  • 3.9K
  • 08 Dec 2020
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