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Topic Review
Aircraft Noise
Aircraft noise is noise pollution produced by aircraft during the various phases of a flight. Sound production is divided into three categories: Health consequences include sleep disturbance, hearing impairment and heart disease, as well as workplace accidents caused by stress. Memory and recall can also be affected. Governments have enacted extensive controls that apply to aircraft designers, manufacturers, and operators, resulting in improved procedures and cuts in pollution.
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  • 26 Oct 2022
Topic Review
Omega-3 and Omega-6 Fatty Acids
Omega-3 fatty acids v(ω-3 FAs) such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) and omega-6 fatty acids (ω-6 FAs) such as linoleic acid and arachidonic acid are important fatty acids responsible for positive effects on human health. The main sources of ω-3 FAs and ω-6 FAs are marine-based products, especially fish oils.
  • 2.7K
  • 25 Jul 2023
Topic Review
Application of Silver in Medicine and Pharmacy
In the context of the growing resistance of microorganisms to available, widely used antibiotics, silver plays a key role. There is only one known case of bacterial resistance to silver—the Pseudomonas stutzeri strain, which naturally occurs in silver mines. The development of research in the field of coordination chemistry offers great opportunities in the design of new substances in which silver ions can be incorporated. 
  • 2.7K
  • 06 Nov 2023
Topic Review
Potato Affected by Heat and Drought Stress
Potato crop species are highly prone to different abiotic (high-temperature stress, drought, salinity, and mineral stress).
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  • 01 Nov 2022
Topic Review
Understanding Pet Food Attribute Preferences of US Consumers
This encyclopedia entry is dedicated to pet food attributes and builds on the work of Meike Rombach and David Dean. Partial least squares structural equation modelling shows that pet food purchase involvement positively impacts subjective and objective knowledge about pet food. Subjective knowledge appears to be the strongest factor impacting the importance consumers place on all three attributes. This is followed by objective knowledge. Socio-demographic factors such as gender, age, income, and education appear to have a limited impact as predictors for the importance consumers place on the product attributes.
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  • 17 Jan 2022
Topic Review
Mars Oxygen ISRU Experiment
The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) is a technology demonstration on the NASA Mars 2020 rover Perseverance investigating the production of oxygen on Mars. On April 20, 2021, MOXIE produced oxygen from carbon dioxide in the Martian atmosphere by using solid oxide electrolysis. This was the first experimental extraction of a natural resource from another planet for human use. The technology may be scaled up for use in a human mission to the planet to provide breathable oxygen, oxidizer, and propellant; water may also be produced by combining the produced oxygen with hydrogen. The experiment was a collaboration between the Massachusetts Institute of Technology, the Haystack Observatory, the NASA/Caltech Jet Propulsion Laboratory, and other institutions.
  • 2.7K
  • 28 Nov 2022
Topic Review
Secretion Systems of Acinetobacter baumannii
Infections led by Acinetobacter baumannii strains are of great concern in healthcare environments due to the strong ability of the bacteria to spread through different apparatuses and develop drug resistance. Secretion systems have recently been demonstrated to be involved in the pathogenic process, and five types of secretion systems out of the known six from Gram-negative bacteria have been found in A. baumannii. They can promote the fitness and pathogenesis of the bacteria by releasing a variety of effectors. Additionally, antibiotic resistance is found to be related to some types of secretion systems.
  • 2.7K
  • 02 Feb 2023
Topic Review
Mass Spectrometry-Based Single Cell Analysis
Cell-to-cell variation exists within a population of the same cell type due to stochastic gene and protein expression and environmental factors. Studying such cellular heterogeneity is the key to understanding the underlying mechanisms of fundamental biology and complex diseases, highly demanding developments in advanced technologies for molecular profiling at the single-cell level.
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  • 14 Mar 2023
Topic Review
Snap
Snap is a software packaging and deployment system developed by Canonical for operating systems that use the Linux kernel and the systemd init system. The packages, called snaps, and the tool for using them, snapd, work across a range of Linux distributions and allow upstream software developers to distribute their applications directly to users. Snaps are self-contained applications running in a sandbox with mediated access to the host system. Snap was originally released for cloud applications but was later ported to also work for Internet of Things devices and desktop applications.
  • 2.7K
  • 21 Oct 2022
Topic Review
TIG-MIG Hybrid Welding
Tungsten inert gas-metal inert gas hybrid welding (TIG-MIG) combines the advantages of tungsten and metal inert gas welding. It can efficiently produce high-quality weld joints that meet modern manufacturing quality and efficiency requirements. Based on heat transfer, fluid dynamics, and electromagnetic theory, a three-dimensional coupled transient model of arc-droplet interactions in TIG-MIG hybrid welding was established. In this study, the temperature field, flow field, electromagnetic force, pressure, and current density parameters were analyzed in the arc space. The results show that introducing TIG welding has a significant impact on MIG welding.
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  • 13 Jan 2021
Topic Review
Hamburger Flugzeugbau HFB 320 Hansa Jet
The HFB 320 Hansa Jet is a twin-engine, ten-seat business jet that was designed and produced by Germany aircraft manufacturer Hamburger Flugzeugbau between 1964 and 1973. The most recognisable and unconventional feature of the aircraft is its forward-swept wing. The Hansa Jet begun development during the 1960s, the selection of the forward-swept wing can be largely attributed to head engineer Hans Wocke, who had previously worked on the experimental Junkers Ju 287. It possessed a spacious cabin, which was achieved due to its wing design, but was a relatively heavy aircraft, posing some issues during both take-off and landing. On 21 April 1964, the prototype conducted its maiden flight. On 12 May 1965, the first prototype was lost during a test flight, killing Hamburger Flugzeugbau's chief test pilot; several design changes were made to change the Hansa Jet's stall characteristics. Type certification of the Hansa Jet was received during early 1967 and the first deliveries commenced during the following year. The largest customer of the type was the German Air Force , who tasked it with both training and VIP transport duties. During 1973, it was decided to end production of the Hansa Jet. Reasons for the programme's termination include increased competition from newer executive jets, a decline in the value of the US dollar, and the limited sales of the type. The German Air Force continued to operate their Hansa Jets into the early 1990s. A limited number continued to be used amongst civilian operators into the 21st century.
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  • 27 Oct 2022
Topic Review
Large-Scale Geothermal Collector Systems
A Geothermal collector system is a ground heat exchanger connected to a heat pump which provides heating energy from the ground for buildings. A Large-scale geothermal collector systems differ from small systems, which are usually built for individual buildings, in their size and complexity. Typical large-scale geothermal collector systems supply entire settlements with heating and cooling energy via 5th Generation District Heating and Cooling (5GDHC) by using the very Shallow Geothermal Potential (vSGP). They can also be constructed in multiple horizontal layers.
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  • 04 Mar 2022
Topic Review
Hsp70
A molecular weight of 70 kDa (Hsp70) plays a particularly important role in protecting cells and the whole body from various types of stress. These proteins are molecular chaperones that restore the native conformation of partially denatured proteins after exposure to proteotoxic forms of stress and are critical for the folding and intracellular trafficking of de novo synthesized proteins under normal conditions. Hsp70s are expressed at high levels in the central nervous system (CNS) of various animals and protect neurons from various types of stress, including heat shock, hypoxia, and toxins. Numerous molecular and behavioral studies have indicated that Hsp70s expressed in the CNS are important for memory formation. These proteins contribute to the folding and transport of synaptic proteins, modulate signaling cascades associated with synaptic activation, and participate in mechanisms of neurotransmitter release.
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  • 22 Jul 2021
Topic Review
Testis-Determining Factor
An Error has occurred retrieving Wikidata item for infobox Testis-determining factor (TDF), also known as sex-determining region Y (SRY) protein, is a DNA-binding protein (also known as gene-regulatory protein/transcription factor) encoded by the SRY gene that is responsible for the initiation of male sex determination in therian mammals (placental mammals and marsupials). SRY is an intronless sex-determining gene on the Y chromosome. Mutations in this gene lead to a range of disorders of sex development (DSD) with varying effects on an individual's phenotype and genotype. TDF is a member of the SOX (SRY-like box) gene family of DNA-binding proteins. When complexed with the SF1 protein, TDF acts as a transcription factor that causes upregulation of other transcription factors, most importantly SOX9. Its expression causes the development of primary sex cords, which later develop into seminiferous tubules. These cords form in the central part of the yet-undifferentiated gonad, turning it into a testis. The now-induced Leydig cells of the testis then start secreting testosterone, while the Sertoli cells produce anti-Müllerian hormone. SRY gene effects normally take place 6–8 weeks after fetus formation which inhibits the female anatomical structural growth in males. It also works towards developing the dominant male characteristics.
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  • 25 Oct 2022
Topic Review
Application of Laser-Induced Periodic Surface Structures (LIPSS)
As a laser technology, the femtosecond laser is used in biomedical fields due to its excellent performance—its ultrashort pulses, high instantaneous power, and high precision. As a surface treatment process, the femtosecond laser can prepare different shapes on metal surfaces to enhance the material’s properties, such as its wear resistance, wetting, biocompatibility, etc. Laser-induced periodic surface structures (LIPSSs) are a common phenomenon that can be observed on almost any material after irradiation by a linearly polarized laser. Surface texturing by laser irradiation can change various materials’ properties and create multifunctional surfaces. Materials can be better applied by customizing functional surfaces.
  • 2.7K
  • 04 Nov 2022
Topic Review
17O in Hydrological Cycle
17O is the one of the naturally occurring stable isotopes of oxygen, and also it has the lowest abundance, 0.038%(). The distribution of isotopes in hydrological systems is controlled by isotope fractionation processes. Oxygen isotopes fractionate through mass-dependent isotopic fractionation, which includes kinetic processes, isotopic exchange reactions, and physicochemical phenomena (diffusion, condensation, and evaporation).
  • 2.7K
  • 03 Aug 2021
Topic Review
Lunar Orbital Platform – Gateway
The Lunar Orbital Platform – Gateway (LOP-G) is a future space station in lunar orbit intended to serve as a solar-powered communications hub, science laboratory, short-term habitation module, and holding area for rovers and other robots. While the project is led by NASA, the Gateway is meant to be developed, serviced, and utilized in collaboration with commercial and international partners. It will serve as the staging point for robotic and crewed exploration of the lunar south pole, and is the proposed staging point for NASA's Deep Space Transport concept. The science disciplines to be studied on the Gateway are expected to include planetary science, astrophysics, Earth observations, heliophysics, fundamental space biology, and human health and performance. Under current plans, this scientific activity will start after the first crewed landing (Artemis 3). Gateway development includes all of the International Space Station partners: ESA, NASA, Roscosmos, JAXA, and CSA. Construction is planned to take place in the 2020s. The International Space Exploration Coordination Group (ISECG), which is composed of 14 space agencies including NASA, has concluded that LOP-G will be critical in expanding a human presence to the Moon, Mars, and deeper into the Solar System. Formerly known as the Deep Space Gateway, the station was renamed in NASA's 2018 proposal for the 2019 United States federal budget. When the budgeting process was complete, US$450 million had been committed by Congress to preliminary studies.
  • 2.7K
  • 26 Oct 2022
Topic Review
Internationalized Country Code Top-Level Domain
An internationalized country code top-level domain is a top-level domain in the Domain Name System (DNS) of the Internet. IDN ccTLDs are specially encoded domain names that are displayed in an end user application, such as a web browser, in their language-native script or alphabet, such as the Arabic alphabet, or a non-alphabetic writing system, such as Chinese characters. IDN ccTLDs are an application of the internationalized domain name system to top-level Internet domains assigned to countries, or independent geographic regions. Although the domain class uses the term code, some of these ccTLDs are not codes but full words. For example, السعودية (as-Suʻūdiyya) is not an abbreviation of "Saudi Arabia", but the common short-form name of the country in Arabic. Countries with internationalized ccTLDs also retain their traditional ASCII-based ccTLDs. As of August 2018 there are 59 approved internationalized country code top-level domains, of them at least 47 used. The most used are .рф (Russia) with over 900,000 domains names, .台灣 (Taiwan) with around 500,000 and .中国 (China) with over 200,000 domains. Still as of 2018 around 20 countries using non-Latin script do not have an internationalized country code top-level domain, including Japan .
  • 2.7K
  • 10 Nov 2022
Topic Review
Prophet, Seer, and Revelator
Prophet, seer, and revelator is an ecclesiastical title used in the Latter Day Saint movement. The Church of Jesus Christ of Latter-day Saints (LDS Church) is the largest denomination of the movement, and it currently applies the terms to the members of the First Presidency and the Quorum of the Twelve Apostles. In the past, it has also been applied to the Presiding Patriarch of the church and the Assistant President of the Church. Other sects and denominations of the movement also use these terms.
  • 2.7K
  • 25 Nov 2022
Topic Review
Biological Barriers to Oral Drug Delivery Systems
The oral route is the most preferred route for systemic and local drug delivery. However, the oral drug delivery system faces the harsh physiological and physicochemical environment of the gastrointestinal tract, which limits the bioavailability and targeted design of oral drug delivery system.
  • 2.7K
  • 08 Feb 2023
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