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Telework: Before and after COVID-19
Telework is, today, a voluntary form of work organization in which the employee is located outside the employer’s premises, at home or elsewhere, under a telework contract, uses information and communication technologies (ICT) and works according to a predetermined schedule on the basis of an agreed supervisory mechanism and an online reporting system on the work undertaken.
  • 3.7K
  • 19 Jul 2022
Topic Review
Direct Synthesis of Silicon Compounds
The development of industrial organosilicon chemistry, and thus the development of silicon chemistry, is partly related to the discovery of the direct process of organosilanes synthesis in the 1940s, which allowed the production of organosilanes and silicone polymers on a large scale, and resulted in the development of new technologies to produce organosilicon monomers and polymers. The direct synthesis process, also known as the Müller–Rochow process, is one of the best-known industrial processes for obtaining organosilicon compounds, and has been the basis of the silicone industry.
  • 3.7K
  • 08 Mar 2023
Topic Review
Materials Used for Customized Healing Abutment
A customized healing abutment is designed by modifying the size and transmucosal shape of the healing abutment to mimic the natural profile of an emerging tooth. 
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  • 22 Dec 2022
Topic Review
Ram Pickup
The Ram pickup (formerly the Dodge Ram pickup) is a full-size pickup truck manufactured by FCA US LLC (formerly Chrysler Group LLC) and marketed as of 2011 onwards under the Ram Trucks brand. The current fifth-generation Ram debuted at the 2018 North American International Auto Show in Detroit, Michigan in January of that year. Previously, Ram was part of the Dodge line of light trucks. The name Ram was first used in 1932–1954 Dodge Trucks, then returned on the redesigned 1981 Ram and Power Ram, following the retiring and rebadging of the Dodge D Series pickup trucks as well as B-series vans. Ram trucks have been named Motor Trend magazine's Truck of the Year six times; the second-generation Ram won the award in 1994, the third-generation Ram Heavy Duty won the award in 2003, the fourth-generation Ram Heavy Duty won in 2010 and the fourth-generation Ram 1500 won in 2013 and 2014, and the current fifth-generation Ram 1500 won in 2019.
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  • 08 Nov 2022
Topic Review
Sacred Grove
A sacred grove or sacred woods are any grove of trees that are of special religious importance to a particular culture. Sacred groves feature in various cultures throughout the world. They were important features of the mythological landscape and cult practice of Celtic, Baltic, Germanic, ancient Greek, Near Eastern, Roman, and Slavic polytheism, and continue to occur in locations such as India, Japan, and West Africa. Examples of sacred groves include the Greco-Roman temenos, various Germanic words for sacred groves, and the Celtic nemeton, which was largely but not exclusively associated with Druidic practice. During the Northern Crusades, there was a common practice of building churches on the sites of sacred groves. The Lakota and various other North American tribes consider particular forests or other natural landmarks to be sacred. Singular trees which a community deems to hold religious significance are known as sacred trees.
  • 3.7K
  • 28 Nov 2022
Topic Review
Laser-Induced Breakdown Spectroscopy
Laser-Induced Breakdown Spectroscopy (LIBS) has been firstly introduced and proposed for analytical applications almost immediately after the invention of the laser in 1960. Since then, it has been proposed and today is widely used as an alternative analytical method for numerous applications. The operating principle of LIBS is quite simple and is based on the interaction of a powerful enough laser beam, focused usually on or in a sample, inducing a dielectric breakdown of the material, thus resulting in plasma formation consisting of excited and non-excited atoms and molecules, fragments of molecular species, electrons and ions, and emitting characteristic radiations, whose spectroscopic analysis can in principle provide the elemental composition fingerprint of the material. The required instrumentation consisting basically of a laser source, and a spectrometer/monochromator equipped with the appropriate light detector (nowadays being almost exclusively some CCD or ICCD type detector) is relatively simple and economically affordable, while significant progresses have been achieved to small size and/or portable equipment, facilitating largely the in situ operation.
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  • 31 Aug 2021
Topic Review
Armenian Highlands
The Armenian Highlands (Armenian: Հայկական լեռնաշխարհ, romanized: Haykakan leṙnašxarh; also known as the Armenian Upland, Armenian plateau, or Armenian tableland) is the most central and the highest of the three plateaus that together form the northern sector of Western Asia. Clockwise starting from the west, the Armenian Highlands are bounded by the Anatolian plateau, the Caucasus, the Kura-Aras lowlands, the Iranian Plateau, and Mesopotamia. The highlands are divided into western and eastern regions, defined by the Ararat Valley where Mount Ararat is located. Western Armenia is nowadays referred to as eastern Anatolia, and Eastern Armenia as the Lesser Caucasus or Caucasus Minor, and historically as the Anti-Caucasus, meaning "opposite the Caucasus". During the Iron Age, the region was known by variations of the name Ararat (Urartu, Uruatri, Urashtu). Later, the Highlands were known as Armenia Major, a central region to the history of Armenians, and one of the four geopolitical regions associated with Armenians, the other three being Armenia Minor, Sophene, and Commagene. The population of the region has been primarily Armenian for most of its known history. Prior to the appearance of nominally Armenian people in historical records, historians have hypothesized that the region must have been home to various ethnic groups who became homogenous when the Armenian language came to prominence. The population of the Armenian Highlands seem to have had a high level of regional genetic continuity for over 6,000 years. Recent studies have shown that the Armenian people are indigenous to the Armenian Highlands and form a distinct genetic isolate in the region. The region was also inhabited during Antiquity by minorities such as Assyrians, Georgians, Greeks, Jews, and Iranians. During the Middle Ages, Arabs and particularly Turkmens and Kurds settled in large numbers in the Armenian Highlands. The Christian population of the western half of the region was exterminated during the Armenian genocide of 1915. Today, the eastern half is mainly inhabited by Armenians, Azerbaijanis and Georgians, while the western half is mainly inhabited by Kurds (including Yazidis), Turks, Azerbaijanis, Armenians (included crypto-Armenians and Hemshins) and Zazas. The region was administered for most of its known history by Armenian nobility and states, whether it was as part of a fully independent Armenian state, as vassals, or as part of a foreign state. Since the 1040s, the highlands have been under the rule of various Turkic peoples and the Safavid dynasty, with pockets of Armenian autonomy in places such as Artsakh. Much of Eastern Armenia, which had been ruled by the Safavids from the 16th century, became part of the Russian Empire in 1828 and was later incorporated into the Soviet Union, while much of Western Armenia was under the rule of the Ottoman Empire and later incorporated into Turkey. Today, the region is divided between Turkey, Georgia, Armenia, Azerbaijan and Iran.
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  • 07 Nov 2022
Topic Review
Secure Shell Protocol
The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. Typical applications include remote command-line, login, and remote command execution, but any network service can be secured with SSH. SSH provides a secure channel over an unsecured network by using a client–server architecture, connecting an SSH client application with an SSH server. The protocol specification distinguishes between two major versions, referred to as SSH-1 and SSH-2. The standard TCP port for SSH is 22. SSH is generally used to access Unix-like operating systems, but it can also be used on Microsoft Windows. Windows 10 uses OpenSSH as its default SSH client and SSH server. SSH was designed as a replacement for Telnet and for unsecured remote shell protocols such as the Berkeley rsh and the related rlogin and rexec protocols. Those protocols send information, notably passwords, in plaintext, rendering them susceptible to interception and disclosure using packet analysis. The encryption used by SSH is intended to provide confidentiality and integrity of data over an unsecured network, such as the Internet.
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  • 29 Sep 2022
Topic Review
Runaway Climate Change
Runaway climate change or runaway global warming is hypothesized to follow a tipping point in the climate system, after accumulated climate change initiates a reinforcing positive feedback. This rapid acceleration in climate change may lead to potentially irreversible damage to the climate system, making timely mitigation efforts unfeasible. This is thought to cause the climate to rapidly change until it reaches a new stable condition. These phrases may be used with reference to concerns about rapid global warming. Some astronomers use the expression runaway greenhouse effect to describe a situation where the climate deviates catastrophically and permanently from the original state—as happened on Venus. Although these terms are rarely used in the peer-reviewed climatological literature, that literature does use the similar phrase "runaway greenhouse effect", which refers specifically to climate changes that cause a planetary body's water to boil off.
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  • 01 Nov 2022
Topic Review
LGD Theory for Nanoscale Ferroelectrics
This is a entry of the Landau-Ginzburg-Devonshire (LGD) Theory applied for description of nanoscale ferroelectrics. The polarization switching kinetics of nanosized ferroelectric crystals and the transition between homogeneous and domain switching in the nanoscale ferroelectric films are considered. Homogeneous switching according to the Ginzburg-Landau-Devonshire (LGD) theory is possible only in two-dimensional (2D) ferroelectrics. The main condition for the applicability of the LGD theory in such systems is its homogeneity along the polarization switching direction. A review is given of the experimental results for two-dimensional (2D) films of a ferroelectric polymer, nanosized barium titanate nanofilms, and hafnium oxide-based films. For ultrathin 2D ferroelectric polymer films, the results are confirmed by first-principle calculations. Fitting of the transition region from homogeneous to domain switching by sigmoidal Boltzmann functions was carried out. Boltzmann function fitting data enabled us to estimate correctly the region sizes of the homogeneous switching in which the LGD theory is valid. These sizes contain several lattice constants or monolayers of a nanosized ferroelectrics.
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  • 14 Jan 2021
Topic Review
Occupational Safety and Health Management System Standards
Occupational accidents present a momentous effect on human well-being and, in addition, create large costs in any country’s social health/insurance system. Moreover, the topic of “safety and health” (OSH, OS&H) or “health and safety” (OHS, OH&S) concerning labor (or occupational work) is one of the most significant issues in any corporation. OSHMS systems were developed as a consequence of a plethora of several and severe industrial accidents throughout the decades of the 1970s and 1980s (for example, the Flixborough accident in 1974, the Seveso incident in 1976, and the Piper Alpha disaster in 1987). Thorough examinations of these events revealed insufficiencies in the dominant techniques for the regulation and the management of OSH and determined the necessity to use approaches that methodically address both engineering and educational action. The proliferation of OSH management systems, which have been used worldwide since the 1990s, has dramatically increased the concentration of performance measurement methods, tools, and techniques.
  • 3.7K
  • 04 Nov 2022
Topic Review Peer Reviewed
Nanotechnology-Enabled COVID-19 mRNA Vaccines
COVID-19 mRNA vaccines contain synthetic mRNA sequences encoded for the Spike proteins expressed on the surface of SARS-CoV-2, and utilize the host cells to produce specific antigens that stimulate both humoral and cellular immunities. Lipid nanoparticles are essential to facilitate the intracellular delivery of the mRNA to its action site, the ribosome, to fully exert its effect.
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  • 13 Apr 2022
Topic Review
Hydrogen Evolution Reaction
In recent years, heteroatom doping has been found to be an effective strategy to improve the electrocatalytic hydrogen evolution reaction (HER) performances of nickel-based catalysts in acidic, neutral, and alkaline media. 
  • 3.7K
  • 26 Oct 2020
Topic Review Peer Reviewed
COVID-19: Evidenced Health Disparity
Health disparity is an unacceptable, unjust, or inequitable difference in health outcomes among different groups of people that affects access to optimal health care, as well as deterring it. Health disparity adversely affects disadvantaged subpopulations due to a higher incidence and prevalence of a particular disease or ill health. Existing health disparity determines whether a disease outbreak such as coronavirus disease 2019, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), will significantly impact a group or a region. Hence, health disparity assessment has become one of the focuses of many agencies, public health practitioners, and other social scientists. Successful elimination of health disparity at all levels requires pragmatic approaches through an intersectionality framework and robust data science.
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  • 13 Apr 2022
Topic Review
Windows 10 Version History (Version 1809)
The Windows 10 October 2018 Update (also known as version 1809 and codenamed "Redstone 5") is the sixth major update to Windows 10 and the fifth in a series of updates under the Redstone codenames. It carries the build number 10.0.17763.
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  • 08 Nov 2022
Topic Review
Choleretic and Cholagogic Effects of Anticholelithiatic Plants
A large number of people suffer from gall stone worldwide and this problem is now being increased significantly due to the malnutrition, changes in living style, lack of exercise and conditions i.e. industrialization. Medicinal plants are used from centuries due to their cultural acceptability, efficacy, safety and fewer side effects as compared to modern synthetic medicines.
  • 3.7K
  • 15 Aug 2022
Topic Review
Single-Speed Bicycle
A single-speed bicycle is a type of bicycle with a single gear ratio. These bicycles are without derailleur gears, hub gearing or other methods for varying the gear ratio of the bicycle. There are many types of modern single speed bicycles; BMX bicycles, most bicycles designed for children, cruiser type bicycles, classic commuter bicycles, unicycles, bicycles designed for track racing, fixed-gear road bicycles, and single-speed mountain and cyclocross bikes. Although most fixed-gear bicycles (fixies) are technically single speed, the term single-speed generally refers to a single gear ratio bicycle with a freewheel mechanism to allow it to coast.
  • 3.7K
  • 20 Oct 2022
Topic Review
IEEE 802.11ax-2021
IEEE 802.11ax-2021 or 802.11ax is an IEEE standard for wireless local-area networks (WLANs) and the successor of 802.11ac. It is marketed as Wi-Fi 6 (2.4 GHz and 5 GHz) and Wi-Fi 6E (6 GHz) by the Wi-Fi Alliance. It is also known as High Efficiency Wi-Fi, for the overall improvements to Wi-Fi 6 clients under dense environments. It is designed to operate in license-exempt bands between 1 and 7.125 GHz, including the 2.4 and 5 GHz bands already in common use as well as the much wider 6 GHz band (5.925–7.125 GHz in the US). The main goal of this standard is enhancing throughput-per-area[lower-alpha 1] in high-density scenarios, such as corporate offices, shopping malls and dense residential apartments. While the nominal data rate improvement against 802.11ac is only 37%,:qt the overall throughput improvement (over an entire network) is 400% (hence High Efficiency).:qt This also translates to 75% lower latency. The quadruplication of overall throughput is made possible by a higher spectral efficiency. The key feature underpinning 802.11ax is orthogonal frequency-division multiple access (OFDMA), which is equivalent to cellular technology applied into Wi-Fi.:qt Other improvements on spectrum utilization are better power-control methods to avoid interference with neighboring networks, higher order 1024‑QAM, up-link direction added with the down-link of MIMO and MU-MIMO to further increase throughput, as well as dependability improvements of power consumption and security protocols such as Target Wake Time and WPA3. The IEEE 802.11ax-2021 standard was approved in February 9th, 2021.
  • 3.7K
  • 11 Nov 2022
Topic Review
Kaleidoscope
A kaleidoscope (/kəˈlaɪdəskoʊp/) is an optical instrument with two or more reflecting surfaces (or mirrors) tilted to each other at an angle, so that one or more (parts of) objects on one end of the mirrors are seen as a regular symmetrical pattern when viewed from the other end, due to repeated reflection. The reflectors are usually enclosed in a tube, often containing on one end a cell with loose, colored pieces of glass or other transparent (and/or opaque) materials to be reflected into the viewed pattern. Rotation of the cell causes motion of the materials, resulting in an ever-changing view being presented.
  • 3.7K
  • 04 Nov 2022
Topic Review
Chemical Composition of Kombucha
Kombucha is a fermented sweetened tea with a mixed fermenting culture of yeast and acetic acid bacteria. The proponents of kombucha consumption tout the varied health benefits it can provide. The final kombucha flavor and composition is a function of both the initial tea used and the fermentation process.
  • 3.7K
  • 29 Aug 2022
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