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Topic Review
Ascorbic Acid-Induced Reactions
Ascorbic acid is the most well-known vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis. Ascorbic acid can be used as a substrate or mediator in organic synthesis. In this review, we report ascorbic acid-catalyzed reactions in organic synthesis. Several examples are included in this review to demonstrate that ascorbic acid is a versatile catalyst for the synthesis of diverse organic compounds. Reactions catalyzed by ascorbic acid are performed in organic or aqueous media. The readily available and easy handling features of ascorbic acid make these procedures highly fascinating.
  • 5.0K
  • 25 Nov 2020
Topic Review
Fountain (Duchamp)
Fountain is a readymade sculpture produced by Marcel Duchamp in 1917: a porcelain urinal signed "R.Mutt". In April 1917, an ordinary piece of plumbing chosen by Duchamp was rotated 90 degrees on its axis and submitted for an exhibition of the Society of Independent Artists, the first annual exhibition by the Society to be staged at The Grand Central Palace in New York. Fountain was not rejected by the committee but it was removed from the show area, since Society rules stated that all works would be accepted from artists who paid the fee. Following that removal, Fountain was photographed at Alfred Stieglitz's studio, and the photo published in The Blind Man. The original has been lost. The work is regarded by art historians and theorists of the avant-garde as a major landmark in 20th-century art. Sixteen replicas were commissioned by Duchamp in the 1950s and 1960s and made to his approval. Some scholars have suggested that the original work was by a female artist rather than Duchamp, but this is a minority view among historians.
  • 5.0K
  • 28 Nov 2022
Topic Review
Aircraft Livery
An aircraft livery is a set of comprehensive insignia comprising color, graphic, and typographical identifiers which operators (airlines, governments, Air force s and occasionally private and corporate owners) apply to their aircraft. As aircraft liveries evolved in the years after the Second World War, they became a leading subset of the emerging disciplines of corporate identity and branding and among the most prominent examples of fashion. They have provided an arena for the work of distinguished designers and eminent lay people like Raymond Loewy, Alexander Girard, and Jacqueline Kennedy Onassis. The term is an adaptation of the word livery: the uniform-style clothing worn by servants of wealthy families and government representatives until the early/mid-20th century. With the advent of stagecoaches, railway trains, and steamships, the term livery spread to their decoration. Since the 1950s, elements of airline liveries permeated ground vehicles, advertising, proprietary airport furniture, airline promotional materials and aircrew uniforms in an increasingly integrated manner, spreading to airline websites in the 1990s. Since the 1950s and 60s, aircraft liveries have usually been uniform livery across an entire fleet. One-off custom-designs might be applied from time to time to individual fleet members to highlight set occasions.
  • 5.0K
  • 21 Oct 2022
Topic Review
Cheese By-Products
Cheese whey (CW) is nowadays recognized as a source of functional and bioactive compounds, especially proteins and peptides. However, a large proportion of the whey produced worldwide is still not valorized. This results from the fact that small and medium size dairy industries lack dimension to make the necessary investments for CW valorization. In some countries such as Portugal, Spain, Italy and Turkey, CW is employed in the production of whey cheeses. The liquid remaining after whey cheese production represents more than 90% of the original whey and is called second cheese whey (SCW). SCW is a poorly studied by-product and there is little interest in its recovery. SCW is a poorly studied by-product and there is little interest in its recovery. Some authors studied the use of SCW for conversion into biofuel and as a biotechnological substrate for fermented products while others studied its potential for the production of fermented drinks. However, half of CW and almost all SCW are not valorized for human consumption. This review presents several alternatives for the valorization of both by-products.
  • 5.0K
  • 20 May 2021
Topic Review
Modern Computing in Iran
Iran’s modern computing history can be divided into four distinct periods: (1) Computers were first introduced to Iran in 1962. As a result, the introduction of computers in Iran occurred approximately ten years after introducing computers in developed countries. (2) Computer development, Iran’s computer development era began in 1971 and lasted until 1981. This path was followed by a lot of competition to buy hardware, introduce massive software systems, recruit more manpower, and follow rigorous programs based on the country’s technological realities. (3) Computer revisit: As a result of the Islamic Revolution, improvements and innovations in computers occurred, and a series of general reviews were conducted until 1980. (4) Technological maturity and growth in Iran: Following the reopening of universities in 1983, the next stage of computer development began, with software and hardware becoming widely available. The Persian language and script processing is among this century’s most important works.
  • 5.0K
  • 29 Aug 2022
Topic Review
Compaq Presario 2200
The Compaq Presario 2200 is a small form factor desktop PC produced by Compaq from 1997 to 1998. It was produced as a slim, small form factor machine mainly intended for budget-minded consumers. When launched, it had 16 MB of EDO DRAM that was expandable up to 80 MB and a Cyrix MediaGXi microprocessor, clocking at 180 MHz. It did not include an Ethernet port; however, the modem can be swapped out for a compatible 8-bit ISA Ethernet card to allow the computer to be connected to the Internet or a LAN network. There are no USB ports on the computer, even though the small metal flap might suggest that Compaq considered installing USB ports during the time the computer was developed. This computer model is not to be confused with the newer Compaq Presario 2200 laptop computer.
  • 5.0K
  • 09 Nov 2022
Topic Review Peer Reviewed
Novel Bioactive Extraction and Nano-Encapsulation
An extraction technology works on the principle of two consecutive steps that involves mixture of solute with solvent and the movement of soluble compounds from the cell into the solvent and its consequent diffusion and extraction. The conventional extraction techniques are mostly based on the use of mild/high temperatures (50–90 °C) that can cause thermal degradation, are dependent on the mass transfer rate, being reflected on long extraction times, high costs, low extraction efficiency, with consequent low extraction yields. Due to these disadvantages, it is of interest to develop non-thermal extraction methods, such as microwave, ultrasounds, supercritical fluids (mostly using carbon dioxide, SC-CO2), and high hydrostatic pressure-assisted extractions which works on the phenomena of minimum heat exposure with reduced processing time, thereby minimizing the loss of bioactive compounds during extraction. Further, to improve the stability of these extracted compounds, nano-encapsulation is required. Nano-encapsulation is a process which forms a thin layer of protection against environmental degradation and retains the nutritional and functional qualities of bioactive compounds in nano-scale level capsules by employing fats, starches, dextrins, alginates, protein and lipid materials as encapsulation materials.
  • 5.0K
  • 13 Apr 2022
Topic Review
Thomson Reuters Business Classification
The Thomson Reuters Business Classification (TRBC) is an industry classification of global companies, developed in 2004; it is owned and operated by Thomson Reuters and is also the basis for Thomson Reuters Indices.
  • 5.0K
  • 28 Nov 2022
Topic Review
Guccifer 2.0
"Guccifer 2.0" is a persona which claimed to be the hacker(s) that hacked into the Democratic National Committee (DNC) computer network and then leaked its documents to the media, the website WikiLeaks, and a conference event. Some of the documents "Guccifer 2.0" released to the media appear to be forgeries cobbled together from public information and previous hacks, which had been mixed with disinformation. According to indictments in February 2018, the persona is operated by Russian military intelligence agency GRU. On July 13, 2018, Special Counsel Robert Mueller indicted 12 GRU agents for allegedly perpetrating the cyberattacks. The U.S. Intelligence Community concluded that some of the genuine leaks from "Guccifer 2.0" were part of a series of cyberattacks on the DNC committed by two Russian military intelligence groups, and that "Guccifer 2.0" is actually a persona created by Russian intelligence services to cover for their interference in the 2016 U.S. presidential election. This conclusion is based on analyses conducted by various private sector cybersecurity individuals and firms, including CrowdStrike, Fidelis Cybersecurity, FireEye's Mandiant, SecureWorks, ThreatConnect, Trend Micro, and the security editor for Ars Technica. The Russian government denies involvement in the theft, and "Guccifer 2.0" denied links to Russia. WikiLeaks founder Julian Assange said multiple parties had access to DNC emails and that there was "no proof" Russia was behind the attack. In March 2018, Special Counsel Robert Mueller took over investigation of Guccifer 2.0 from the FBI while it was reported that forensic determination had found the Guccifer 2.0 persona to be a "particular military intelligence directorate (GRU) officer working out of the agency's headquarters on Grizodubovoy Street in Moscow".
  • 5.0K
  • 10 Oct 2022
Topic Review
False Vacuum
In quantum field theory, a false vacuum is a hypothetical vacuum that is somewhat, but not entirely, stable. It may last for a very long time in that state, and might eventually move to a more stable state. The most common suggestion of how such a change might happen is called bubble nucleation – if a small region of the universe by chance reached a more stable vacuum, this "bubble" (also called "bounce") would spread. A false vacuum exists at a local minimum of energy and is therefore not stable, in contrast to a true vacuum, which exists at a global minimum and is stable. It may be very long-lived, or metastable.
  • 5.0K
  • 24 Oct 2022
Topic Review
Over the Shoulder Shot
The over the shoulder shot (OTS) is a camera angle used in film and television, where the camera is placed above the back of the shoulder and head of a subject. This shot is most commonly used to present conversational back and forth between two subjects. With the camera placed behind one character, the shot then frames the sequence from the perspective of that character. The over the shoulder shot is then utilised in a shot-reverse-shot sequence where both subject's OTS perspectives are edited consecutively to create a back and forth interplay, capturing dialogue and reactions. This inclusion of the back of the shoulder allows audiences to understand the spatial relationships between two subjects, while still being able to capture a closer shot of each subject’s facial expression. In film and television, the filmmaker or cinematographer’s choice of an OTS shot’s camera height, the use of focus and lenses affect the way audiences interpret subjects and their relationships to others and space.
  • 5.0K
  • 02 Dec 2022
Topic Review
Solketal
Solketal (CAS 100–79–8) has low viscosity at room temperature (~11 cP) and freezing, boiling, and flash points of about −26 °C, 190 °C, and 80 °C, respectively. The density is 1.06 g/cm3 and the vapor pressure is 107.32 mmHg. It has low toxicity, slight odor, and it is non-irritant for humans; due to these characteristics and to the renewable origin, it is considered an environmentally friendly substance. It is completely miscible in water and in most organic compounds, which endows its solvent capacity.
  • 5.0K
  • 07 May 2021
Topic Review
Sorbent-Based Microextraction of Natural Toxins from Food Samples
Natural toxins are chemical substances that are not toxic to the organisms that produce them, but which can be a potential risk to human health when ingested through food. Thus, it is of high interest to develop advanced analytical methodologies to control the occurrence of these compounds in food products. Current trends in sample preparation involve moving towards “greener” approaches by scaling down analytical operations, miniaturizing the instruments and integrating new advanced materials as sorbents. The combination of these new materials with sorbent-based microextraction technologies enables the development of high-throughput sample preparation methods, which improve conventional extraction and clean-up procedures.
  • 5.0K
  • 05 Nov 2021
Topic Review
Titin and Muscle Atrophy
Titin, also called connectin, is a giant sarcomere protein, which functions as a spring for muscle extension and elasticity. Titin interconnects the contraction of actin-containing thin filaments and myosin-containing thick filaments. Recently, the N-terminal fragment of titin, which is the breakdown product of titin, has become measurable using an enzyme-linked immunosorbent assay kit (27900 titin N-fragment Assay Kit; Immuno-Biological Laboratories, Fujioka, Japan). This kit has been used to evaluate muscle breakdown in muscle dystrophy, in which the level of urinary titin N-fragment was 700-times above the normal level.
  • 5.0K
  • 20 Apr 2021
Topic Review
Odor Measurement Methods
Odor pollution related to industrial activities (e.g., chemical industries, oil and gas extraction and refining facilities, waste treatment and disposal facilities) is nowadays acknowledged as a serious environmental concern. Indeed, odors are currently subjected to control and regulation in many countries. Such regulations rely on the possibility of measuring odors. The methods that have been developed and standardized over the last years to measure odors, thereby including sensorial and instrumental techniques, are here described, thereby focusing on their applicability and limitations.
  • 5.0K
  • 08 Feb 2022
Topic Review
Sustainable Energy Consumption in Developing Country
Since energy consumption in developing countries has increased significantly, motivating energy-saving habits among citizens is an important issue both from the academic and industrial perspectives.
  • 5.0K
  • 09 Aug 2022
Topic Review
Shielding of Cosmic Radiation by Fibrous Materials
Cosmic radiation belongs to the challenges engineers have to deal with when further developing space travel. Besides the severe risks for humans due to high-energy particles or waves, the impact of cosmic radiation on electronics and diverse materials cannot be neglected, even in microsatellites or other unmanned spacecraft. Here, we explain the different particles or waves found in cosmic radiation and their potential impact on biological and inanimate matter.
  • 5.0K
  • 20 Oct 2021
Topic Review
Five-Membered Heterocyclic Compounds
Heterocyclic compounds are a class of compounds of natural origin with favorable properties and hence have major pharmaceutical significance. They have an exceptional adroitness favoring their use as diverse smart biomimetics, in addition to possessing an active pharmacophore in a complex structure. This has made them an indispensable motif in the drug discovery field. Heterocyclic compounds are usually classified according to the ring size, type, and the number of heteroatoms present in the ring.
  • 5.0K
  • 16 Aug 2022
Topic Review
Gyro-Stabilized Camera Systems
Gyro-stabilized camera systems use modern electronic position data to correct for movements of the platforms they are mounted on to enable a high degree of stabilization. The systems often use a multi-axis gyro stabilization to enable the use of zoom lenses and high definition capture, despite the high amounts of vibrations and movements in aircraft, helicopters or other vehicles. The applications range from security and military operations, law enforcement, ENG, sports broadcasting documentary, natural history, and feature film productions..
  • 5.0K
  • 14 Oct 2022
Topic Review Peer Reviewed
Age-Friendly Built Environment
Age-friendly built environments have been promoted by the World Health Organisation (WHO, Geneva, Switzerland) under the Global Age-friendly Cities (AFC) movement in which three domains are related to the built environment. These are: housing, transportation, outdoor spaces and public buildings. The aim is to foster active ageing by optimising opportunities for older adults to maximise their independent living ability and participate in their communities to enhance their quality of life and wellbeing. An age-friendly built environment is inclusive, accessible, respects individual needs and addresses the wide range of capacities across the course of life. Age-friendly housing promotes ageing in familiar surroundings and maintains social connections at the neighbourhood and community levels. Both age-friendly housing and buildings provide barrier-free provisions to minimise the needs for subsequent adaptations. Age-friendly public and outdoor spaces encourage older adults to spend time outside and engage with others against isolation and loneliness. Age-friendly public transport enables older adults to get around and enhances their mobility. For achieving an age-friendly living environment, a holistic approach is required to enable independent living, inclusion and active participation of older adults in society. The eight domains of the AFC movement are not mutually exclusive but overlap and support with one another.
  • 5.0K
  • 13 Apr 2022
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