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Topic Review
Cavity Disinfectants
Cavity disinfection becomes an important step before a dental restorative procedure. The disinfection can be obtained cleaning the dental cavity with antimicrobial agents before the use of adhesive systems. 
  • 2.5K
  • 27 Jan 2021
Topic Review
Pacific Temperate Rainforests (WWF Ecoregion)
The Pacific temperate rainforests ecoregion of North America is the largest temperate rain forest ecoregion on the planet as defined by the World Wildlife Fund (other definitions exist). The Pacific temperate rain forests lie along the western side of the Pacific Coast Ranges along the Pacific Northwest Coast of North America from the Prince William Sound in Alaska through the British Columbia Coast to Northern California, and are part of the Nearctic ecozone, as also defined by the World Wildlife Fund. The Pacific temperate rain forests are characterized by a high amount of rainfall, in some areas more than 300 cm (10 ft) per year and moderate temperatures in both the summer and winter months (10–24 °C or 50–75 °F). This ecoregion is a subregion of the Cascadia bioregion. These rain forests occur in a number of ecoregions, which vary in their species composition, but are predominantly of conifers, sometimes with an understory of broadleaf trees, ferns and shrubs. In the WWF's system, sub-ecoregions of the Pacific Temperate Rain Forests Ecoregion are the Northern Pacific coastal forests, Haida Gwaii, British Columbia mainland coastal forests, Central Pacific coastal forests, Central and Southern Cascades forests, Klamath-Siskiyou forests, and Northern California coastal forests ecoregions. The forests in the north contain predominantly Sitka spruce and western hemlock, while those in the coastal forests are home as well to coast redwood (Sequoia sempervirens), coast Douglas-fir (Pseudotsuga menziesii), western redcedar and shore pine. Notably, the three tallest species of trees are found here. Dense growths of epiphytes and mosses cover the trees, and lush vegetation is present everywhere. Hardwood trees such as the bigleaf maple and the alder are also common, especially at lower elevations and along stream banks, and are vital to the ecosystem, in part because of their nitrogen fixing.
  • 2.5K
  • 03 Nov 2022
Topic Review
Deathtrap (Plot Device)
A deathtrap is a literary and dramatic plot device in which a villain who has captured the hero or another sympathetic character attempts to use an elaborate, improbable, and usually sadistic method of murdering them. It is often used as a means to create dramatic tension in the story and to have the villain reveal important information to the hero, confident that the hero will shortly not be able to use it. It may also be a means to show the hero's resourcefulness in escaping, or the writer's ingenuity at devising a last-minute rescue or deus ex machina.
  • 2.5K
  • 04 Nov 2022
Topic Review
Cycling
Cycling, also called bicycling or biking, is the use of bicycles for transport, recreation, exercise or sport. People engaged in cycling are referred to as "cyclists", "bicyclists", or "bikers". Apart from two-wheeled bicycles, "cycling" also includes the riding of unicycles, tricycles, quadracycles, recumbent and similar human-powered vehicles (HPVs). Bicycles were introduced in the 19th century and now number approximately one billion worldwide. They are the principal means of transportation in many parts of the world. Cycling is widely regarded as a very effective and efficient mode of transportation optimal for short to moderate distances. Bicycles provide numerous benefits in comparison with motor vehicles, including the sustained physical exercise involved in cycling, easier parking, increased maneuverability, and access to roads, bike paths and rural trails. Cycling also offers a reduced consumption of fossil fuels, less air or noise pollution, and much reduced traffic congestion. These lead to less financial cost to the user as well as to society at large (negligible damage to roads, less road area required). By fitting bicycle racks on the front of buses, transit agencies can significantly increase the areas they can serve. In addition, cycling provides a variety of health benefits. The World Health Organization (WHO) states that cycling can reduce the risk of cancers, heart disease, and diabetes that are prevalent in sedentary lifestyles. Cycling on stationary bikes have also been used as part of rehabilitation for lower limb injuries, particularly after hip surgery. Individuals who cycle regularly have also reported mental health improvements, including less perceived stress and better vitality. Among the disadvantages of cycling are the requirement of bicycles (excepting tricycles or quadracycles) to be balanced by the rider in order to remain upright, the reduced protection in crashes in comparison to motor vehicles, often longer travel time (except in densely populated areas), vulnerability to weather conditions, difficulty in transporting passengers, and the fact that a basic level of fitness is required for cycling moderate to long distances.
  • 2.5K
  • 15 Nov 2022
Topic Review
Maximum Genetic Diversity
Maximum Genetic Diversity (MGD) is a scientific hypothesis relating to molecular evolution, which is the study of how and why populations of organisms experience genetic changes over time. MGD starts with the observation that some regions of the genome are more likely to preserve mutations into the next generation than others. This difference in the observed rate of mutation means some regions of the genome appear to mutate faster than others, and is theorized to relate to balancing the preservation of vital information relating to a species' function against its ability to mutate and adapt to new environmental niches. According to MGD, these regions of the genome eventually drift into two rough categories: faster-mutating sections tuned to respond quickly to environmental pressures and allow adaptive radiation, as well as slower-mutating sections involved in an organism's most fundamental instructions. Because MGD asserts that only slow-mutating genes accurately reflect shared evolutionary history, relationships between species can alternatively be calculated by their "maximum genetic diversity," which is determined by measuring the frequency of mutations in specific corresponding regions of orthologous genes instead of using raw overall genetic similarity. Using calculations based on mutations in these slow-mutating genes provides a chart of genetic ancestry that lines up with the fossil record – measurements based on raw genetic similarity yield results that clash with the fossil record. Also due to this grouping into fast and slow, MGD hypothesizes that over time complex organisms become genetically fragile and less tolerant to mutation as their MGD decreases, since an increasing proportion of their genome will have become slow-mutating over time. MGD asserts that this is because increased organismal and social complexity means more of the genome is needed to preserve the expanding instructional manual necessary for complex behavior and function, and so more of an organism's genome must become slow-mutating as the organism increases in complexity, since being slow-mutating preserves and protects those vital instructions. MGD seeks to reconcile the inconsistencies observed around the neutral theory of molecular evolution, whose "original lines of evidence... are now falsified" according to a paper published in Oxford's Molecular Biology and Evolution in 2018. One example of this is that supposedly consistent and neutral mutation rates from proteins across a wide range of species were demonstrably not neutral nor consistent. Another study published in Nature in December 2019 noted that "defining the evolutionary time scales according to the molecular clock is intrinsically biased, especially for proteins of complex organisms." Although a number of other arguments have been proposed against the neutral theory in recent years, there is not a yet a consensus that the neutral theory is entirely falsified and counter-arguments against the role of selection do exist. Furthermore, beyond the fact that MGD is still relatively unknown, it also contradicts the current paradigm in molecular evolution, since the neutral theory's fundamental premises are still nearly ubiquitously utilized in genetic analysis and admixture studies. Additionally, some of the phenomena explained by MGD could theoretically be accounted for by other processes such as gene conversion or concerted evolution. Lastly, even if the neutral theory is disproved, it does not necessarily validate MGD, as alternative theories have been proposed that also incorporate the effects of selection on the genome. And so MGD will have to be more rigorously tested against any alternative theories before becoming widely adopted. However, to date MGD has not been contradicted in peer-reviewed literature, and its assumptions and framework have been confirmed when it comes to examining the ratio of brain-specific proteins in a range of mammals, for classifying and timing the evolutionary genetic structure of a wide range of organisms ranging from yeast to primates, by evaluating the genetic fitness of yeast which become more genetically fragile as they become more fit, by a genetic model that seeks to more accurately model not only the location of mutations but the rate at which they occur, and by the observation that vital slow-mutating genes are more protected by "transcriptional scanning" in mammalian testes than fast-evolving genes involved with responding quickly to environmental challenges.
  • 2.5K
  • 25 Nov 2022
Topic Review
Biogenic Synthesis
Recent advances in the research of therapeutic plant and nanotechnology has been on the increase. Significantly in the green synthesis of metallic nanoparticles (MNPs) because of its numerous gains over conventional methods. Biological conventions for synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) are through the use of nature’s biolaboratory such as plant, microorganisms, alga, carbohydrates and biopolymers . Medicinal plant is a choice natural reserve for different phytochemicals in the synthesis of biogenic MNPs. Thus, they are deemed a green, sustainable, and efficient route for the biosynthesis of MNPs owing to their benign and environmentally friendly nature. In this review we discussed the mode of synthesis strategies and the proposed mechanism of biocidal antibacterial activity of MNPs.  The focus is on the synthesis and possible antibacterial mechanism of specific MNPs such as silver (Ag), gold (Au) and their bimetallic synthesized from plants. This is to give a synergistic view of the efficacy of plant mediated MNPs for the prospect of antibiotic development.
  • 2.5K
  • 17 Nov 2020
Topic Review
Binding Materials for MOF Monolith Shaping Processes
The fabrication of porous Metal Organic Framework materials within resistant structures is a key challenge impeding their wide commercial use for processes such as adsorptive separation. In fact, the integration of nano-scale Metal–organic frameworks (MOFs)  crystallic structures into bulk components that can maintain the desired characteristics, for example, size, shape, and mechanical stability, is a prerequisite for their wide practical use in many applications. At the same time, it requires sophisticated shaping techniques that can structure nano/micro-crystalline fine powders of MOFs into diverse types of macroscopic bodies such as monoliths.
  • 2.5K
  • 01 Mar 2022
Topic Review
Place Branding and Territorial Brand
Place branding is linked to economic development, which includes tourism as a product. The territorial brand also has these two approaches, a mercantilist perspective and one linked with tourism. However, the brand of a product and the brand of a territory have differences in the way they are created, communicated, and managed. 
  • 2.5K
  • 23 Jun 2022
Topic Review
Cooking Mama
Cooking Mama (クッキング ママ, Kukkingu Mama) is a cookery simulation-styled minigame compilation video game for the Nintendo Wii, Nintendo DS, and iOS platforms, developed by Office Create and published by Taito, Majesco Entertainment, and 505 Games. It was awarded IGN's "Best Of E3" award for 2006. It was followed by a sequel for the DS, Cooking Mama 2: Dinner with Friends. Two games have been made for the Wii: Cooking Mama and Cooking Mama.
  • 2.5K
  • 19 Oct 2022
Topic Review
The Pathophysiology of Post-Traumatic Stress Disorder
Post-Traumatic Stress Disorder (PTSD) is characterized by a wide-ranging set of symptoms including but not limited to intrusive and distressing memories, dissociative reactions, and serious psychological distress in response to stimuli that resemble a previously experienced traumatic event. 
  • 2.5K
  • 26 Oct 2023
Topic Review
LED Lighting Systems for Horticulture
       In recent years, research on light emitting diodes (LEDs) has highlighted their great potential as a lighting system for plant growth, development and metabolism control. The suitability of LED devices for plant cultivation has turned the technology into a main component in controlled or closed plant-growing environments, experiencing an extremely fast development of horticulture LED metrics. In this context, the hereby study aims to provide an insight into the current global horticulture LED industry and the present features and potentialities for LEDs’ applications. An updated review of this industry has been integrated through a database compilation of 301 manufacturers and 1473 LED lighting systems for plant growth. The research identifies Europe (40%) and North America (29%) as the main regions for production. Additionally, the current LED luminaires’ lifespans show 10 and 30% losses of light output after 45,000 and 60,000 working hours on average, respectively, while the vast majority of worldwide LED lighting systems present efficacy values ranging from 2 to 3 μmol J−1 (70%). Thus, an update on the status of the horticultural LED sector, applications and metrics, and the intense innovation are described and discussed.
  • 2.5K
  • 30 Oct 2020
Topic Review
Lanthanide-Doped Nanoparticles
Lanthanide-doped nanoparticles exhibit unique luminescent properties, including tunable luminescence emission, narrow emission width, excellent optical stability, and long lifetimes from microseconds to milliseconds. Lanthanide-doped nanomaterials with long lifetimes are independent with background fluorescence interference and biological tissue depth.
  • 2.5K
  • 22 Feb 2022
Topic Review
Nanofillers for Property Enhancement in Bioplastics
Bioplastics reinforced with filler enhance the mechanical properties of starch but reduce its hydrophilicity. In recent years, utilization of nano-sized fillers has bloomed in the fabrication of bioplastic due to their merits, such as low density, excellent mechanical properties, low abrasive nature and reactive surface for ease of modification. Numerous studies had reported that nano-sized fillers have a larger surface area than the conventional micro-sized fillers, thus enhancing the properties due to better interfacial interactions with the polymer matrix. Besides enhancing the mechanical and barrier properties, fillers are also capable of imparting specific functional properties to the bioplastics, e.g., electric conductivity or an antimicrobial character. Another added advantage of filler with nanoscale is in retaining the inherent transparency of the film, especially for the neat matrix. 
  • 2.5K
  • 02 Mar 2022
Topic Review
Drug Delivery Systems Polymeric Nanocarriers in Cancer Therapy
Conventional chemotherapy is the most common therapeutic method for treating cancer by the application of small toxic molecules that interact with DNA and cause cell death. Unfortunately, these chemotherapeutic agents are non-selective and can damage both cancer and healthy tissues, producing diverse side effects, and they can have a short circulation half-life and limited targeting. Many synthetic polymers have found application as nanocarriers of intelligent drug delivery systems (DDSs). Their unique physicochemical properties allow them to carry drugs with high efficiency, specifically target cancer tissue and control drug release. In recent years, considerable efforts have been made to design smart nanoplatforms, including amphiphilic block copolymers, polymer-drug conjugates and in particular pH- and redox-stimuli-responsive nanoparticles (NPs).
  • 2.5K
  • 25 Mar 2022
Topic Review
Modern Small Farming and Homesteading: Automate and Simplify
Since the outbreak of COVID-19 pandemic, increasing number of people from the urban environment have moved to rural areas in search for more peaceful and healthier lifestyle. They do keep their city jobs, mostly working online, and aren't interested into agriculture besides limited production for their own needs. However, as they are accustomed to the use of ICT and electronics in everyday life, they would appreciate any device that would robotize, automate or simplify common jobs on property maintenance, which in turn would provide additional time for other activities. Despite the fact that the application of WSN and IoT in agriculture has been researched for 20 years, and although there has been a significant breakthrough in agricultural robotics, the automation of small farming machines is still scarce, which may prove to be the next new big thing for small equipment manufacturers and startups.
  • 2.5K
  • 11 Apr 2022
Topic Review
Verse of Mawadda
The Verse of Mawadda (Arabic: آية الْمَوَدَّة) refers to verse 42:23 of the Quran, the interpretation of which is disputed. This verse is often cited in Shia sources to support the elevated status of the family of the Islamic prophet Muhammad, known as the Ahl al-Bayt. Most Sunni authors reject the Shia view and offer various alternatives.
  • 2.5K
  • 02 Nov 2022
Topic Review
Aviation Spline Research
Splines are irreplaceable in high-speed aviation fields due to their simplicity, reliability, and high specific power. Aviation splines are not only subjected to severe operating mechanical loads, but also sometimes operate under grease-lubricated and non-lubricated environments. All of this results in aviation splines suffering widespread failures.
  • 2.5K
  • 03 Apr 2023
Topic Review
Archaea Pigments
Archaea represent a resource of great potential for the identification of new metabolites because of their adaptation to extreme environmental conditions and their original metabolic pathways, allowing the synthesis of unique biomolecules. Archaea also represent a valuable source of novel pigments, including carotenoids (detailed further below) and proteins called bacteriorhodopsins.
  • 2.5K
  • 02 Sep 2022
Topic Review
Dhyāna Sutras
The Dhyāna sutras (Chinese: 禪経) or "meditation summaries" (Chinese: 禪要) are a group of early Buddhist meditation texts which are mostly based on the Yogacara[note 1] meditation teachings of the Sarvāstivāda school of Kashmir circa 1st-4th centuries CE. Most of the texts only survive in Chinese and were key works in the development of the Buddhist meditation practices of Chinese Buddhism.
  • 2.5K
  • 09 Oct 2022
Topic Review
Auger Electron Spectroscopy
thumb|A Hanford scientist uses an Auger electron spectrometer to determine the elemental composition of surfaces. Auger electron spectroscopy (AES; pronounced [oʒe] in French) is a common analytical technique used specifically in the study of surfaces and, more generally, in the area of materials science. Underlying the spectroscopic technique is the Auger effect, as it has come to be called, which is based on the analysis of energetic electrons emitted from an excited atom after a series of internal relaxation events. The Auger effect was discovered independently by both Lise Meitner and Pierre Auger in the 1920s. Though the discovery was made by Meitner and initially reported in the journal Zeitschrift für Physik in 1922, Auger is credited with the discovery in most of the scientific community. Until the early 1950s Auger transitions were considered nuisance effects by spectroscopists, not containing much relevant material information, but studied so as to explain anomalies in X-ray spectroscopy data. Since 1953 however, AES has become a practical and straightforward characterization technique for probing chemical and compositional surface environments and has found applications in metallurgy, gas-phase chemistry, and throughout the microelectronics industry.
  • 2.5K
  • 01 Nov 2022
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