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Topic Review
Digital PCR and plant studies
Digital PCR (dPCR) is a breakthrough technology that able to provide sensitive and absolute nucleic acid quantification. It is a third-generation technology in the field of nucleic acid amplification. A unique feature of the technique is that of dividing the sample into numerous separate compartments, in each of which an independent amplification reaction takes place. Several instrumental platforms have been developed for this purpose, and different statistical approaches are available for reading the digital output data.
  • 2.6K
  • 16 Dec 2020
Topic Review
Biomethanation Facilities in Europe
In line with the long-term strategy of the European Union to become climate-neutral, the energy storage challenge that is induced by volatile renewable electricity production (e.g., with rapidly growing photovoltaic capacities) must be handled. The power-to-methane technology is promising for long-term, high-capacity energy storage. Currently, there are two different industrial-scale methanation methods: the chemical one (based on the Sabatier reaction) and the biological one (using microorganisms for the conversion). The second method can be used not only to methanize the mixture of pure hydrogen and carbon dioxide but also to methanize the hydrogen and carbon dioxide content of low-quality gases, such as biogas or deponia gas, enriching them to natural gas quality; therefore, the applicability of biomethanation is very wide.
  • 2.6K
  • 08 Oct 2021
Topic Review
Measuring Intraocular Pressure for Various Tonometers
Intraocular pressure (IOP) is an important measurement that needs to be taken during ophthalmic examinations, especially in ocular hypertension subjects, glaucoma patients, and patients with risk factors for developing glaucoma. The gold standard technique in measuring IOP is still Goldmann applanation tonometry (GAT); however, this procedure requires local anesthetics, can be difficult in patients with scarce compliance, surgical patients, and children, and is influenced by several corneal parameters. Numerous tonometers have been proposed in the past to address the problems related to GAT. The research describes the various devices currently in use for the measurement of intraocular pressure (IOP), highlight the main advantages and limits of the various tools. The continuous monitoring of IOP, which is still under evaluation, will be an important step for a more complete and reliable management of patients affected by glaucoma.
  • 2.6K
  • 18 Apr 2023
Topic Review
Utilize Human Kinetic Energy for Sustainable Energy Generation
Renewable energy has become increasingly relevant in recent years as concerns about climate change and the depletion of fossil fuels have grown across the globe. The energy generated through exercise, sports, and other forms of physical exertion can be harnessed and used to generate electricity for homes, businesses, and even communities. This type of energy generation is becoming increasingly popular as a means of generating renewable energy and reducing our dependence on non-renewable sources of energy.
  • 2.6K
  • 18 Jul 2023
Topic Review
Warp-Field Experiments
Warp-field experiments are a series of current and proposed experiments to create and detect instances of spacetime warping. The ultimate goal is to prove or disprove the possibility of spacetime metric engineering with reasonable amounts of energy.
  • 2.6K
  • 14 Oct 2022
Topic Review
Eugenol-based O/W Emulsion by Low-energy Emulsification
Emulsions are systems formed by two immiscible liquids, one of which is dispersed in the other as droplets with a relative stability. These have multiple applications, among them, in the formulation of pharmaceutical and cosmetic products. Its preparation requires generating a large interfacial area, which is usually attained by using the physicochemical formulation know-how on surfactant-oil-water (SOW) systems. Among the applications in the pharmaceutical industry, topical creams, and emulsions for intravenous and for oral administration can be found.  Eugenol can be extracted from cloves (Syzygium aromaticum) by various methods, including steam distillation, hydrodistillation and Soxhlet extraction. Furthermore, emulsions based on eugenol can be obtained for a variety of applications, including as topical and oral anesthetic. Nanoemulsions can be formulated with a mixture of non-ionic surfactants Span 20/Tween 80 at an HLB of 11 to 13 and a total surfactant concentration of 4%, using the dilution phase transition method (so-called spontaneous emulsification) to attain stable O/W eugenol-based emulsions. Paraffin oil/eugenol ratio of 4/1 can be used to reach a final emulsion internal oil phase content of 10% with 4% surfactant and 86% aqueous phase. Different polymers are used as viscosifiers, including carboxymethylcellulose. Under these conditions, eugenol-based emulsions with an average droplet size of less than 2 μm can be attained, with topical and oral anesthetic characteristics.
  • 2.6K
  • 03 Apr 2022
Topic Review
Dietary Natural Compounds and Vitamins Impact Uterine Fibroids
Within the past 20 year-span concerning risks of uterine fibroids (UFs) occurrence and dietary factors was carried out. A link between Vitamin D deficiency and UFs formation is strongly indicated, making it a potent compound in leiomyoma therapy. Analogs of the 25-hydroxyvitamin D3, not susceptible to degradation by tissue 24-hydroxylase, appear to be especially promising and tend to show better therapeutic results. Although research on the role of Vitamin A in the formation of fibroids is contradictory, Vitamin A-enriched diet, as well as synthetic retinoid analogues, may be preventative or limit the growth of fibroids. Unambiguous conclusions cannot be drawn regarding Vitamin E and C supplementation, except for alpha-tocopherol. Alpha-tocopherol as a phytoestrogen taking part in the modulation of estrogen receptors (ERs) involved in UF etiology, should be particularly avoided in therapy. A diet enriched in fruits and vegetables, as sources of carotenoids, polyphenols, quercetin, and indole-3-carbinol, constitutes an easily modifiable lifestyle element with beneficial results in patients with UFs. Other natural substances, such as curcumin, can reduce the oxidative stress and protect against inflammation in leiomyoma. Although the exact effect of probiotics on uterine fibroids has not yet been thoroughly evaluated at this point, the protective role of dairy products, i.e., yogurt consumption, has been indicated. Trace elements such as selenium can also contribute to antioxidative and anti-inflammatory properties of a recommended diet.
  • 2.6K
  • 11 Mar 2022
Topic Review
Comand APS
Cockpit Management and Data system - COMAND for short - acts as a combined command and control centre for all audio, telematics and telecommunications functions on Mercedes-Benz vehicles and includes a dedicated flat display screen. In addition to the GPS navigation system and general processing and control logic, COMAND includes components such as an address book, telephone, radio and in many cases a CD/DVD drive. It is connected to other (often separate) devices such as CD/DVD changers, sound system and surround sound amplifier, TV receiver and the optional Linguatronic voice control system via an optical fibre network. The first generations of COMAND used the D2B optical network standard whereas later models are based on MOST. A key feature of all COMAND systems is to provide deep integration between the various functions such as multimedia, navigation and telephony and to also allow multiple presentation and control facilities. An example of functional integration is where other audio sources can be muted when a phone call comes in or when navigation guidance is being given. It is also the case that the main audio system, speakers and microphone are used for all these functions instead of being logically and functionally separate. With regard to multiple presentation and control facilities, COMAND based vehicles allow steering wheel controls to be used alongside the main COMAND buttons and controller and COMAND related status information and instructions can be displayed in the instrument cluster in addition to the main COMAND display. On vehicles with a factory fitted Mercedes-Benz rear seat entertainment system, this also provides integration with the COMAND system, allowing for instance the rear seat displays to show content from the COMAND TV receiver or to play out the rear DVD audio over the car's surround sound system. On newer S-Class and CL-Class models such as the W221, the integration between COMAND and other vehicle functions is even more complete, including access via COMAND to the HVAC system, seat controls, etc. On these cars, in contrast to most other Mercedes-Benz vehicles, COMAND is part of the standard specification rather than an optional extra. COMAND was introduced first exclusively on the flagship S-Class and CL-Class models. Later, it became available on other Mercedes cars too.
  • 2.6K
  • 09 Oct 2022
Topic Review
Natural Ventilation
Natural ventilation is the process of supplying air to and removing air from an indoor space without using mechanical systems. It refers to the flow of external air to an indoor space as a result of pressure differences arising from natural forces. There are two types of natural ventilation occurring in buildings: wind driven ventilation and buoyancy-driven ventilation. Wind driven ventilation arises from the different pressures created by wind around a building or structure, and openings being formed on the perimeter which then permit flow through the building. Buoyancy-driven ventilation occurs as a result of the directional buoyancy force that results from temperature differences between the interior and exterior. Since the internal heat gains which create temperature differences between the interior and exterior are created by natural processes, including the heat from people, and wind effects are variable, naturally ventilated buildings are sometimes called "breathing buildings".
  • 2.6K
  • 25 Oct 2022
Topic Review
Principles of Grid Generation
Grids or meshes are geometrical shapes (formed after discretisation of the geometric domain) which are small-sized discrete cells that cover the physical domain, whose objective is to identify the discrete volumes or elements where conservation laws can be applied. They have applications in the fields of computational fluid dynamics (CFD), geography, designing and many more places where numerical solutions to the partial differential equations (PDEs) are required. Numerical grid generation is the crucial initial step involved in computing numerical solutions to the equations that describe a physical process. The accuracy of the solution depends upon the quality of the grid generated. A well-constructed grid can improve the quality of solution whereas, deviations from the numerical solution can be observed with a poorly constructed grid. Techniques for creating the cell forms the basis of grid generation. Various methods for the grid generation are discussed below.
  • 2.6K
  • 28 Oct 2022
Topic Review
Body Image Disturbance
Body image disturbance (BID) is a common symptom in patients with eating disorders. The onset is mainly attributed to patients with anorexia nervosa who persistently tend to subjectively discern themselves as average or overweight despite adequate, clinical grounds for a classification of being severely underweight. The symptom is an altered perception of one's body and a severe state of bodily dissatisfaction characterizing the body image disturbance. It is included among the diagnostic criteria for anorexia nervosa in DSM-5 (criterion C). The disturbance is associated with significant bodily dissatisfaction and is a source of severe distress, often persisting even after seeking treatment for an eating disorder, and is regarded difficult to treat. Thus, effective body image interventions could improve the prognosis in patients with ED, as experts have suggested. Unfortunately, there is no hard evidence that current treatments for body image disturbance effectively reduce eating disorders' symptoms. Furthermore, pharmacotherapy is ineffective in reducing body misperception and it has been used to focus on correlated psychopathology (e.g., mood or anxiety disorders). However, to date, research and clinicians are developing new therapies as virtual reality experiences, mirror exposure or multisensory integration body techniques, which have shown some extent of efficacy.
  • 2.6K
  • 22 Nov 2022
Topic Review
Isoquinolone
Isoquinolones (isoquinolin-1(2H)-ones): the atom- and step-economic syntheses.
  • 2.6K
  • 14 Jul 2021
Topic Review
Owner and Cat Relationship
This entry provides a short overview of the different ways cat owners describe the relationship with their cat, how this might relate to an antropomorphic view of (role of) the cat, which owner-and cat-related charateristics are related to such views and how different views are associated with different living environments of cats.  
  • 2.6K
  • 24 Jan 2022
Topic Review
Implementation of Fourth Industrial Revolution Technologies
The fourth industrial revolution (4iR) technologies offer an opportunity for the construction industry to improve health and safety (H&S) compliance. Therefore, implementing the technologies is of top priority to improve the endless H&S incidents in construction projects, which lead to poor quality of work, late project delivery, and increased worker injury claims. Central to improving the nature of work and other industrial processes, the 4iR technologies have emerged. Concurrent with this trend is the importance of 4iR technologies in enhancing health and safety performance on construction sites. 
  • 2.6K
  • 19 Apr 2022
Topic Review
Red Mud resources for metal
Various scopes are suggested for the utilization of red mud to maintain a sustainable environment. The potential use of red mud covers the valuable metal recovery that could emphasize the use of red mud as a resource. Red mud could act as reduced slag in the metallurgical field for the extraction of minerals and metals for upscale application. Although many studies have revealed the potential utilization of red mud, most of them are only limited to a lab-scale basis. 
  • 2.6K
  • 09 Jul 2021
Topic Review
Recurrent and Residual Caries with Resin Composite Restorations
Caries is the most widely prevailing noncommunicable disease, and is a multifactorial process presently considered as biofilm-mediated rather than an infectious disease. According to the ecological plaque hypothesis, caries occurs as a result of an imbalance of oral microflora—normally more than 700 species—leading to an increase in cariogenic bacteria such as Streptococcus mutans and Lactobacilli types. The accumulating cariogenic bacteria produce acids such as lactic acid that reduce the local pH, leading first to demineralization and later to the destruction of the organic matrix. Caries progresses when demineralization cycles prevail and remineralization cycles cease. Classically, bacterial proteases are blamed for the proteolytic process taking place because of dental caries. Recently, it has become increasingly evident that activated endogenous matrix metalloproteinases (MMPs) and cystine cathepsins of salivary, gingival crevicular fluid and dentinal origin, together with bacterial proteases, share in degrading the dentin matrix of demineralized dentin. This takes place at neutralized pH levels where the buffering effect of saliva takes place, since MMPs operate only in neutral pH values.
  • 2.6K
  • 24 Nov 2022
Topic Review
Tungsten Resources in Mine Waste
Tungsten is recognized as a critical metal due to its unique properties, economic importance, and limited sources of supply. It has wide applications where hardness, high density, high wear, and high-temperature resistance are required, such as in mining, construction, energy generation, electronics, aerospace, and defense sectors. The two primary tungsten minerals, and the only minerals of economic importance, are wolframite and scheelite. Secondary tungsten minerals are rare and generated by hydrothermal or supergene alteration rather than by atmospheric weathering. There are no reported concerns for tungsten toxicity. However, tungsten tailings and other residues may represent severe risks to human health and the environment. Tungsten metal scrap is the only secondary source for this metal but reprocessing of tungsten tailings may also become important in the future.
  • 2.6K
  • 12 Jul 2021
Topic Review
Measuring Overtourism
The tourism debate prior to the COVID-19 pandemic was dominated by the problems inherent in overtourism, reflecting an inadequate land management. Although publications on overtourism have grown exponentially in recent years, its scientific study still has major shortcomings, particularly with regard to measurement. With the aim of overcoming this insufficiency, we have carried out a review of the literature (using the mapping review method) and, based on its conclusions, we have drawn up a proposal to systematise the measurement of overtourism by combining several tools: indicators, surveys, interviews, and other tools linked to the Internet and social networks. The results of the research make a contribution to the expansion of the literature on the topic and may have important practical implications in formulating effective land-use policies by guiding policy makers in the management of overtourism. They could be of use in both the early detection of overtourism and the design of policies that prevent and/or detect situations of risk and that correct existing problems. This is especially relevant in the current international context to implement the effective transition to a responsible tourism model post-COVID-19.
  • 2.6K
  • 06 Sep 2021
Topic Review
Teeth Eruption Disorders
Dental eruption refers to the vertical displacement of a tooth from its initial non-functional towards its functional position. Tooth eruption disorders may be expressed in various clinical conditions, which may be grouped as “primary retention” and “secondary retention”.  Tooth eruption disorders can be manifested in several clinical conditions where the oral location, the number of the affected teeth, and the etiology of the disorders vary considerably. Eruption failure is often attributed to genetic factors.
  • 2.6K
  • 27 Jul 2022
Topic Review
Panama Papers (Africa)
The Panama Papers are 11.5 million leaked documents that detail financial and attorney–client information for more than 214,488 offshore entities. The documents, some dating back to the 1970s, were created by, and taken from, Panamanian law firm and corporate service provider Mossack Fonseca, and were leaked in 2015 by an anonymous source. This page details related allegations, reactions, and investigations, in Africa. Former South African president Thabo Mbeki, head of the African Union's panel on illicit financial flows, on April 9 called the leak "most welcome" and called on African nations to investigate the citizens of their nations who appear in the papers. His panel's 2015 report found that Africa loses $50 billion a year due to tax evasion and other illicit practices and its 50-year losses top a trillion dollars. Furthermore, he said, the Seychelles, an African nation, is the fourth most mentioned tax haven in the documents.
  • 2.6K
  • 25 Nov 2022
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