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Topic Review
Gold and Silver Nanoparticle-Based Colorimetric Sensors
Gold and Silver nanoparticles (AuNPs and AgNPs) are perfect platforms for developing sensing colorimetric devices thanks to their high surface to volume ratio and distinctive optical properties, particularly sensitive to changes in the surrounding environment. These characteristics ensure high sensitivity in colorimetric devices. Au and Ag nanoparticles can be capped with suitable molecules that can act as specific analyte receptors, so highly selective sensors can be obtained.
  • 3.6K
  • 23 Nov 2021
Topic Review
Sound Transmission Losses in DPS
Double panel structures (DPS) are flat or curved structural designs which consist of two opposite facesheets or panels separated by a core or cavity. The cavity may be any kind of enclosed gasses while the core may be any form of solid materials which can be architecturally designed. DPS have been used in various applications for sound insulation purpose.  First, sound incident on the incident facesheet of the DPS, transmitted through the core or cavity and then radiates from the radiating facesheet of the DPS. The ratio of the sound power incident on the incident facesheet to the sound power transmitted through the radiating facesheet is referred as the sound transmission loss of the DPS. The motivation behind the wide industrial application of DPS is owing to their potential characteristics to absorb sound more effectively. Therefore, it is of utmost importance to understand the different geometry and material constituents of the facesheets as well as core/cavity of the DPS. The knowledge of this will help designers and manufacturers to produce the most effective and optimal design of DPS capable of producing very high and desirable sound transmission losses.
  • 3.6K
  • 19 Aug 2020
Topic Review
Prestressed Concrete Girders
Prestressing methods were used to realize long-span bridges in the last few decades. For their maintenance, dynamic nondestructive procedures for identifying prestress losses were mainly developed since serviceability and safety of Prestressed Concrete (PC) girders depend on the effective state of prestressing. In fact, substantial long term prestress losses can induce excessive deflections and cracking in PC bridge girders. However, old unsolved problematics exist since a variation in prestress force does not significantly affect the vibration responses of such PC girders. As a result, this makes uncertain the use of natural frequencies as appropriate parameters for prestress loss determinations. Thus, amongst emerging techniques, static identification based on vertical deflections has preliminary proved to be a reliable method. In fact, measured vertical deflections take accurately and instantaneously into account the changes of structural geometry of PC girders due to prestressing losses. Given the current state of methodologies, the manuscript represents a state-of-the-art review of some important works on determining prestress losses. The attention is principally focused on a static nondestructive method, and a comparison with dynamic ones is elaborated.
  • 3.6K
  • 05 Nov 2020
Topic Review
Neuroprotective Effects of Quercetin
Quercetin is a flavonoid compound present in a wide variety of vegetables and fruit, such as onion, asparagus, red leaf lettuce, cilantro, lovage, dill, capers, apples, and berries. Quercetin represents the highest percentage of total flavonoid intake and is the most important component of flavonol subclass, often the base of other flavonoids. Thus, quercetin has been demonstrated to exert neuroprotective effects in several neurodegenerative disorders as well as antioxidant, anti-inflammatory, anti-cancer, anti-obesity, anti-viral and anti-microbial properties, and cardioprotective and hepatoprotective activities.
  • 3.6K
  • 07 Mar 2021
Topic Review
Optical Camera Communication
Visible Light Communication (VLC) uses various properties of light to encode digital data, which is then modulated and transmitted over a short distance to the receiver. Photodiodes are inexpensive and provide low complexity implementation,  but their adoption requires modifying existing devices to house dedicated sensors. On the other hand, in Optical Camera Communication (OCC), existing camera-based receivers are used to extract encoded data using properties of light like color, blink frequency, intensity, and polarity. Thus, OCC is considered one possible solution to achieve a ready-to-use VLC system by utilizing the camera’s properties, computational capacity of mobile phones, and chromaticity of the light. 
  • 3.6K
  • 12 Jul 2022
Topic Review
Bauxite Tailings
Bauxite tailings, also known as bauxite residue, red mud, red sludge, or alumina refinery residues (ARR), is a highly alkaline waste product composed mainly of iron oxide that is generated in the industrial production of alumina (aluminium oxide, the principal raw material used in the manufacture of aluminium metal and also widely used in the manufacture of ceramics, abrasives and refractories). It is important to differentiate between the alkaline waste generated in the Bayer process and the tailings generated during the mining of bauxite. This article specifically covers the alkaline waste generated when operating the Bayer process. The scale of production makes the waste product an important one, and issues with its storage are reviewed and every opportunity is explored to find uses for it. Over 95% of the alumina produced globally is through the Bayer process; for every tonne of alumina produced, approximately 1 to 1.5 tonnes of bauxite tailings/residue are also produced. Annual production of alumina in 2018 was approximately 126 million tonnes resulting in the generation of over 160 million tonnes of bauxite tailings/residue.
  • 3.6K
  • 02 Nov 2022
Topic Review
Covalent Organic Framework (COFs)
Covalent organic frameworks (COFs) are 2D or 3D low density crystalline porous materials with periodically ordered skeletons constituted by organic molecules linked through covalent bonds. They were first reported by Yaghi and collaborators in 2005 from condensation of benzenediboronic acid (BDBA) alone and in the presence of hexahydroxytriphenylene (HHTP) in a simple one-pot procedure at 120 °C, obtaining a boroxine COF (COF-1) and a boronate ester COF (COF-5), respectively. Since then, there has been steady growth in the number of published works dealing with the synthesis, properties, and catalytic applications of COFs.
  • 3.6K
  • 23 Nov 2021
Topic Review
GeSn Alloys for Photonic and Electronic Applications
GeSn materials have attracted considerable attention for their tunable band structures and high carrier mobilities, which serve well for future photonic and electronic applications.
  • 3.6K
  • 28 Mar 2022
Topic Review
Eclipse
Eclipse is an integrated development environment (IDE) used in computer programming. It contains a base workspace and an extensible plug-in system for customizing the environment. It is the second-most-popular IDE for Java development, and, until 2016, was the most popular. Eclipse is written mostly in Java and its primary use is for developing Java applications, but it may also be used to develop applications in other programming languages via plug-ins, including Ada, ABAP, C, C++, C#, Clojure, COBOL, D, Erlang, Fortran, Groovy, Haskell, JavaScript, Julia, Lasso, Lua, NATURAL, Perl, PHP, Prolog, Python, R, Ruby (including Ruby on Rails framework), Rust, Scala, and Scheme. It can also be used to develop documents with LaTeX (via a TeXlipse plug-in) and packages for the software Mathematica. Development environments include the Eclipse Java development tools (JDT) for Java and Scala, Eclipse CDT for C/C++, and Eclipse PDT for PHP, among others. The initial codebase originated from IBM VisualAge. The Eclipse software development kit (SDK), which includes the Java development tools, is meant for Java developers. Users can extend its abilities by installing plug-ins written for the Eclipse Platform, such as development toolkits for other programming languages, and can write and contribute their own plug-in modules. Since the introduction of the OSGi implementation (Equinox) in version 3 of Eclipse, plug-ins can be plugged-stopped dynamically and are termed (OSGI) bundles. Eclipse software development kit (SDK) is free and open-source software, released under the terms of the Eclipse Public License, although it is incompatible with the GNU General Public License. It was one of the first IDEs to run under GNU Classpath and it runs without problems under IcedTea.
  • 3.6K
  • 08 Oct 2022
Topic Review
Micro-Algal Biotechnology
Environment is everything including both the living and non living things in the earth’s ecosystem. Today the pollution of the environment is a serious concern facing humanity and other life forms in the world. The environment is daily polluted by natural and anthropogenic (man-mad) factors due to inattention and improper use of the existing science and technology. Several physicochemical methods are used for protection of the pollution in the environment but these techniques have its own advantage and disadvantage. In recent years, using biological methods specially, microalgae for environmental pollution protection is the best one, because it is suitable, produce less and or non toxic products, cost effective and eco-friendly methods to our environment. Microalgae are the important groups of living organisms used for biotechnological utilizations such as for environmental protection, Agricultural usage, biofule production, pharmaceutical production etc. without any environmental factor. This review focuses on the environmental applications of micro-algal biotechnology for treatment of wastewater nutrients, removal of heavy metals from the natural water, mitigation of CO2, removal of dyes and dyestuffs from their effluents and their agricultural usage without any factor in the natural environment.
  • 3.6K
  • 30 Oct 2020
Topic Review
CXCL12/CXCR4 Biological Axis and Its Physiological Functions
The CXCL12/CXCR4 biological axis is a coupled molecular pair, which is formed by the interaction of CXCL12 and its corresponding receptor CXCR4, and is closely related to intercellular messaging and cell migration.
  • 3.6K
  • 05 Aug 2022
Topic Review
List of AMD Athlon Microprocessors
Athlon is the name of a family of CPUs designed by AMD, targeted mostly at the desktop market. It has been largely unused as just "Athlon" since 2001 when AMD started naming its processors Athlon XP, but in 2008 began referring to single core 64-bit processors from the AMD Athlon X2 and AMD Phenom product lines. Later the name began being used for some APUs.
  • 3.6K
  • 26 Oct 2022
Topic Review
BibTeX
BibTeX is reference management software for formatting lists of references. The BibTeX tool is typically used together with the LaTeX document preparation system. Within the typesetting system, its name is styled as [math]\displaystyle{ {\mathrm{B{\scriptstyle{IB}} \! T\!_{\displaystyle E} \! X}} }[/math]. The name is a portmanteau of the word bibliography and the name of the TeX typesetting software. The purpose of BibTeX is to make it easy to cite sources in a consistent manner, by separating bibliographic information from the presentation of this information, similarly to the separation of content and presentation/style supported by LaTeX itself.
  • 3.6K
  • 14 Nov 2022
Topic Review
H3K27M-Mutant Diffuse Midline Glioma
H3K27M-mutant diffuse midline glioma is a rare childhood cancer originating in midline brain structures. The H3K27M mutation substitutes an amino acid on histone H3 that promotes gene expression and tumor growth. This cancer has a dismal prognosis and requires new and better treatment approaches. Thus, innovative treatment approaches are greatly needed to improve clinical outcomes for these patients. 
  • 3.6K
  • 01 Sep 2022
Topic Review
Organic Binders in Archaeological Wall Paintings
Binding media are complex materials, employed to allow pigment grains to adhere to each other and to the surface of the support, through the formation of a coherent and homogeneous film. The function of the binder consists, therefore, in keeping the pigment particles firmly together and at the same time adhering them in the form of a coherent thin film to the surface of the support. The binder must obviously be in the fluid state, in order to form with the pigments a stable, homogeneous, stretchy, and viscous dough.   For the realization of wall paintings and, in later times, for their preservation, different materials with functions of binders, adhesives, paints, protective and consolidating were and are still necessary. There is a very large class of products which can have both constitutive functions but also a function of conservation and restoration. 
  • 3.6K
  • 21 Oct 2021
Biography
Abraham Pais
Abraham Pais (/peɪs/; May 19, 1918 – July 28, 2000) was a Dutch-United States physicist and science historian. Pais earned his Ph.D. from University of Utrecht just prior to a Nazi ban on Jewish participation in Dutch universities during World War II. When the Nazis began the forced relocation of Dutch Jews, he went into hiding, but was later arrested and saved only by the end of the war.[1]
  • 3.6K
  • 29 Nov 2022
Topic Review
Pencil (Mathematics)
In geometry, a pencil is a family of geometric objects with a common property, for example the set of lines that pass through a given point in a plane, or the set of circles that pass through two given points in a plane. Although the definition of a pencil is rather vague, the common characteristic is that the pencil is completely determined by any two of its members. Analogously, a set of geometric objects that are determined by any three of its members is called a bundle. Thus, the set of all lines through a point in three-space is a bundle of lines, any two of which determine a pencil of lines. To emphasize the two dimensional nature of such a pencil, it is sometimes referred to as a flat pencil Any geometric object can be used in a pencil. The common ones are lines, planes, circles, conics, spheres and general curves. Even points can be used. A pencil of points is the set of all points on a given line. A more common term for this set is a range of points.
  • 3.6K
  • 10 Oct 2022
Topic Review
Cortana
Cortana is a virtual assistant developed by Microsoft which uses the Bing search engine to perform tasks such as setting reminders and answering questions for the user. Cortana is currently available in English, Portuguese, French, German, Italian, Spanish, Chinese, and Japanese language editions, depending on the software platform and region in which it is used. Microsoft began reducing the prevalence of Cortana and converting it from an assistant into different software integrations in 2019. It was split from Windows 10's search bar in April 2019. In January 2020, Cortana mobile app was removed from certain markets and in first half of 2021 Cortana mobile app was shut down globally.
  • 3.6K
  • 24 Oct 2022
Topic Review
Optical Diffraction Tomography
Optical Diffraction Tomography (ODT) is an emerging tool for label-free imaging of semi-transparent samples in three-dimensional space. Being semi-transparent, such objects do not strongly alter the amplitude of the illuminating field.
  • 3.5K
  • 28 Jan 2022
Topic Review
BPA Controversy
Bisphenol A controversy centers on concerns and debates about the biomedical significance of bisphenol A (BPA), which is a precursor to polymers that are used in some consumer products, including some food containers. The concerns began with the hypothesis that BPA is an endocrine disruptor, i.e. it mimics endocrine hormones and thus has the unintended and possibly far-reaching effects on people in physical contact with the chemical. Since 2008, several governments have investigated its safety, which prompted some retailers to withdraw polycarbonate products. The U.S. Food and Drug Administration (FDA) ended its authorization of the use of BPA in baby bottles and infant formula packaging, based on market abandonment, not safety. The European Union and Canada have banned BPA use in baby bottles. The U.S. FDA states "BPA is safe at the current levels occurring in foods" based on extensive research, including two more studies issued by the agency in early 2014. The European Food Safety Authority (EFSA) reviewed new scientific information on BPA in 2008, 2009, 2010, 2011 and 2015: EFSA's experts concluded on each occasion that they could not identify any new evidence which would lead them to revise their opinion that the known level of exposure to BPA is safe; however, the EFSA does recognize some uncertainties, and will continue to investigate them. In February 2016, France announced that it intends to propose BPA as a REACH Regulation candidate substance of very high concern (SVHC). The European Chemicals Agency agreed to the proposal in June 2017.
  • 3.5K
  • 11 Oct 2022
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