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Topic Review
PDP-10
Digital Equipment Corporation (DEC)'s PDP-10, later marketed as the DECsystem-10, is a mainframe computer family manufactured beginning in 1966 and discontinued in 1983. 1970s models and beyond were marketed under the DECsystem-10 name, especially as the TOPS-10 operating system became widely used. The PDP-10's architecture is almost identical to that of DEC's earlier PDP-6, sharing the same 36-bit word length and slightly extending the instruction set (but with improved hardware implementation). Some aspects of the instruction set are unusual, most notably the byte instructions, which operate on bit fields of any size from 1 to 36 bits inclusive, according to the general definition of a byte as a contiguous sequence of a fixed number of bits. The PDP-10 was found in many university computing facilities and research labs during the 1970s, the most notable being Harvard University's Aiken Computation Laboratory, MIT's AI Lab and Project MAC, Stanford's SAIL, Computer Center Corporation (CCC), ETH (ZIR), and Carnegie Mellon University. Its main operating systems, TOPS-10 and TENEX, were used to build out the early ARPANET. For these reasons, the PDP-10 looms large in early hacker folklore. Projects to extend the PDP-10 line were eclipsed by the success of the unrelated VAX superminicomputer, and the cancellation of the PDP-10 line was announced in 1983. By late 1980 DEC reportedly had sold "about 1500 DECsystem-10s."
  • 3.5K
  • 04 Nov 2022
Topic Review
Titanium Dioxide for Water Purification
Titanium dioxide (TiO2), one of the most frequently used materials in general, has emerged as an excellent photocatalytic material for environmental applications. Here, principles and mechanisms of the photocatalytic activity of TiO2 have been analyzed. Structural and physical specificities of TiO2 nanoparticles, such as morphology, crystal structure, and electronic and optical properties, have been considered in the context of photocatalytic applications.
  • 3.5K
  • 16 Jan 2023
Topic Review
Currently Available Treatments for Periodontal Disease
Periodontitis is an inflammatory infection caused by bacterial plaque accumulation that affects the periodontal tissues. This entry provides a summary of the main features of the periodontium and describes the currently available treatments for periodontal disease.
  • 3.5K
  • 13 Apr 2023
Topic Review
Fossa
The Fossa (Cryptoprocta ferox) is a unique and elusive carnivore native to the island of Madagascar. Resembling a large mongoose or small cougar, the Fossa is the largest carnivorous mammal on the island and is renowned for its agility and prowess as a predator. With its slender body, retractable claws, and sharp teeth, the Fossa is well-adapted to its arboreal habitat and plays a crucial role in regulating prey populations within Madagascar's diverse ecosystems.
  • 3.5K
  • 28 Feb 2024
Topic Review
Extraction Functional Ingredients from Jackfruit
Various studies in the literature showed the effect of conventional and non-conventional extraction methods to obtain jackfruit functional ingredients; among the non-conventional methods, some use emerging technologies to extract or as a pre-treatment. Among the studies using conventional extraction, applying solvents such as methanoland oxalic acidstands out, as well as the extraction with hot water. Regarding extraction by emerging technologies, radio frequency-assistedand supercritical fluid (SFE) with CO2extractions have attracted attention owing to their less negative impact on the environment and safety of the final product obtained in comparison with other methods using non-conventional technologies.
  • 3.5K
  • 26 Aug 2021
Topic Review
Micronutrients
Minerals and trace elements are micronutrients that are essential to the human body but present only in traceable amounts. Nonetheless, they exhibit well-defined biochemical functions. Deficiencies in these micronutrients are related to widespread human health problems such as diabetes, insulin resistance, improper immune function, bone health and brain development. The levels of trace elements may vary considerably among different populations, contingent on the composition of the diet and location. Local differences in selenium, zinc, copper, iron, chromium and iodine in the diet can affect physiological functions leading to malnourishment. Inadequate supply of a number of minerals and trace elements including iodine, selenium, zinc, calcium, chromium, cobalt, iron, boron and magnesium and in a few cases, excess of essential trace elements may lead to imbalances in glucose homeostasis and insulin resistance. Changes in these micronutrient levels in the serum and urine of subjects may signal towards metabolic changes, oxidative stress and other disease-related complications. Adequate supplement of the micronutrients may eliminate or protect against certain diseases such as heart disease.
  • 3.5K
  • 05 Nov 2020
Topic Review
Geothermal Heat Pump
A geothermal heat pump (GHP) or ground source heat pump (GSHP) is a type of heat pump used to heat and/or cool a building by exchanging heat with ground, often through a vapor-compression refrigeration cycle. It uses the earth all the time, without any intermittency, as a heat source (in the winter) or a heat sink (in the summer). This design takes advantage of the moderate temperatures in the ground to boost efficiency and reduce the operational costs of heating and cooling systems, and may be combined with solar heating to form a geosolar system with even greater efficiency. They are also known by other names, including geoexchange, earth-coupled, earth energy systems. The engineering and scientific communities prefer the terms "geoexchange" or "ground source heat pumps" to avoid confusion with traditional geothermal power, which uses a high-temperature heat source to generate electricity. Ground source heat pumps harvest heat absorbed at the Earth's surface from solar energy. The temperature in the ground below 6 metres (20 ft) is roughly equal to the local mean annual air temperature (MAAT). Depending on latitude, the temperature beneath the upper 6 metres (20 ft) of Earth's surface maintains a nearly constant temperature reflecting the mean average annual air temperature (in many areas, between 10 and 16 °C/50 and 60 °F), if the temperature is undisturbed by the presence of a heat pump. Like a refrigerator or air conditioner, these systems use a heat pump to force the transfer of heat from the ground. Heat pumps can transfer heat from a cool space to a warm space, against the natural direction of flow, or they can enhance the natural flow of heat from a warm area to a cool one. The core of the heat pump is a loop of refrigerant pumped through a vapor-compression refrigeration cycle that moves heat. Air source heat pumps are typically more efficient at heating than pure electric heaters, even when extracting heat from cold winter air, although efficiencies begin dropping significantly as outside air temperatures drop below 5 °C (41 °F). A ground source heat pump exchanges heat with the ground. This is much more energy-efficient because underground temperatures are more stable than air temperatures throughout the year. Seasonal variations drop off with depth and disappear below 7 metres (23 ft) to 12 metres (39 ft) due to thermal inertia. Like a cave, the shallow ground temperature is warmer than the air above during the winter and cooler than the air in the summer. A ground source heat pump extracts ground heat in the winter (for heating) and transfers heat back into the ground in the summer (for cooling). Some systems are designed to operate in one mode only, heating or cooling, depending on climate. Geothermal pump systems reach fairly high coefficient of performance (CoP), 3 to 6, on the coldest of winter nights, compared to 1.75–2.5 for air-source heat pumps on cool days. Ground source heat pumps (GSHPs) are among the most energy-efficient technologies for providing HVAC and water heating. Setup costs are higher than for conventional systems, but the difference is usually returned in energy savings in 3 to 10 years. Geothermal heat pump systems are reasonably warranted by manufacturers, and their working life is estimated at 25 years for inside components and 50+ years for the ground loop. As of 2004, there are over one million units installed worldwide providing 12 GW of thermal capacity, with an annual growth rate of 10%.
  • 3.5K
  • 11 Oct 2022
Topic Review
Hydrogen Storage Techniques for On-Board Applications
Hydrogen as an energy carrier could help decarbonize industrial, building, and transportation sectors, and be used in fuel cells to generate electricity, power, or heat. One of the numerous ways to solve the climate crisis is to make the vehicles on our roads as clean as possible. Fuel cell electric vehicles (FCEVs) have demonstrated a high potential in storing and converting chemical energy into electricity with zero carbon dioxide emissions. This text presents the most favorable hydrogen storage approaches for FCEV on-board applications. To achieve long-range autonomy (over 500 km), FCEVs must be capable of storing 5-10 kg of hydrogen in compressed vessels at 700 bar, with Type IV vessels being the primary option. Although physical and chemical storage technologies are expected to be valuable to the hydrogen economy, compressed hydrogen storage remains the most advanced technology for on-board applications.
  • 3.5K
  • 09 Aug 2023
Topic Review
Natural Gas Processing
Natural gas processing plants, or fractionators, are used to purify the raw natural gas extracted from underground gas fields and brought up to the surface by gas wells. The processed natural gas, used as fuel by residential, commercial and industial consumers, is almost pure methane and is very much different from the raw natural gas.
  • 3.5K
  • 28 Sep 2022
Topic Review
Cinnamon (Desktop Environment)
Cinnamon is a free and open-source desktop environment for the X Window System that derives from GNOME 3 but follows traditional desktop metaphor conventions. Cinnamon is the principal desktop environment of the Linux Mint distribution and is available as an optional desktop for other Linux distributions and other Unix-like operating systems as well. The development of Cinnamon began as a reaction to the April 2011 release of GNOME 3 in which the conventional desktop metaphor of GNOME 2 was abandoned in favor of GNOME Shell. Following several attempts to extend GNOME 3 such that it would suit the Linux Mint design goals, the Mint developers forked several GNOME 3 components to build an independent desktop environment. Separation from GNOME was completed in Cinnamon 2.0, which was released in October 2013. Applets and desklets are no longer compatible with GNOME 3. As the distinguishing factor of Linux Mint, Cinnamon has generally received favorable coverage by the press, in particular for its ease-of-use and gentle learning curve. With respect to its conservative design model, Cinnamon is similar to the Xfce and GNOME 2 (MATE and GNOME Flashback/Classic) desktop environments.
  • 3.5K
  • 07 Nov 2022
Topic Review
Fish Skin Mucus Extracts as Antimicrobial Agents
The slow discovery of new antibiotics combined with the alarming emergence of antibiotic-resistant bacteria underscores the need for alternative treatments. In this regard, fish skin mucus has been demonstrated to contain a diverse array of bioactive molecules with antimicrobial properties, including peptides, proteins, and other metabolites. This entry aims to provide an overview of the antimicrobial molecules found in fish skin mucus and its reported in vitro antimicrobial capacity against bacteria, fungi, and viruses. Additionally, the different methods of mucus extraction, which can be grouped as aqueous, organic, and acidic extractions, are presented. Finally, omic techniques (genomics, transcriptomics, proteomics, metabolomics, and multiomics) are described as key tools for the identification and isolation of new antimicrobial compounds.
  • 3.5K
  • 19 Jun 2023
Topic Review
Pharmacological Actions of Quercetin in Diabetes
Quercetin is a flavonoid, present in various natural sources, which has demonstrated in vitro and in vivo antidiabetic properties. It improves oral glucose tolerance, as well as pancreatic β-cell function to secrete insulin. It inhibits the α-glucosidase and DPP-IV enzymes, which prolong the half-life of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Quercetin also suppresses the release of pro-inflammatory markers such as IL-1β, IL-4, IL-6, and TNF-α.
  • 3.5K
  • 09 Aug 2022
Topic Review
Oral Bioavailability of Ellagic Acid
Ellagic acid, a polyphenolic compound present in fruit and berries, has recently been the object of extensive research for its antioxidant activity, which might be useful for the prevention and treatment of cancer, cardiovascular pathologies, and neurodegenerative disorders. Its protective role justifies numerous attempts to include it in functional food preparations and in dietary supplements, and not only to limit the unpleasant collateral effects of chemotherapy. However, ellagic acid use as a chemopreventive agent has been debated because of its poor bioavailability associated with low solubility, limited permeability, first pass effect, and interindividual variability in gut microbial transformations. To overcome these drawbacks, various strategies for oral administration including solid dispersions, micro and nanoparticles, inclusion complexes, self-emulsifying systems, and polymorphs were proposed. Here, we listed an updated description of pursued micro and nanotechnological approaches focusing on the fabrication processes and the features of the obtained products, as well as on the positive results yielded by in vitro and in vivo studies in comparison to the raw material. The micro and nanosized formulations here described might be exploited for pharmaceutical delivery of this active, as well as for the production of nutritional supplements or for the enrichment of novel foods.
  • 3.5K
  • 28 Oct 2020
Topic Review
Yahoo Sports
Yahoo Sports is a sports news website launched by Yahoo! on December 8, 1997. It receives a majority of its information from STATS, Inc. It employs numerous writers, and has team pages for teams in almost every North American major sport. Before the launch of Yahoo Sports, certain elements of the site were known as Yahoo! Scoreboard. From 2011 to 2016, the Yahoo Sports brand had also been used for a U.S. sports radio network. That network is now known as SportsMap.
  • 3.5K
  • 08 Nov 2022
Biography
Hermann Oberth
Hermann Julius Oberth (German: [ˈhɛrman ˈjuːli̯ʊs ˈoːbɛrt]; 25 June 1894 – 28 December 1989) was an Austro-Hungarian-born German physicist and engineer. He is considered one of the founding fathers of rocketry and astronautics, along with the French Robert Esnault-Pelterie, the Russian Konstantin Tsiolkovsky, and the American Robert Goddard.[1][2] Hermann Oberth as a young boy,
  • 3.5K
  • 05 Dec 2022
Topic Review
Technologies for Railway Track Maintenance
Inspection and repair interventions play vital roles in the asset management of railways. Autonomous mobile manipulators possess considerable potential to replace humans in many hazardous railway track maintenance tasks with high efficiency and increased asset utilization. Railway track maintenance technologies ranges from handheld devices to whole train, from manually pushed trolley to autonomous robots. 
  • 3.5K
  • 02 Jun 2023
Topic Review
Alienation
Alienation, in a sociological and philosophical context, refers to a condition in which individuals feel estranged, disconnected, or separated from themselves, others, and the broader society. The concept has its roots in the works of Karl Marx, who developed the idea as a central component of his critique of capitalism. However, the concept of alienation has been explored and expanded upon by various thinkers across different disciplines.
  • 3.5K
  • 25 Jan 2024
Topic Review
Moshi Monsters
Moshi Monsters is a British website aimed at children aged 6-12, with over 80 million registered users in 150 territories worldwide. Users choose from one of six virtual pet monsters (Diavlo, Luvli, Katsuma, Poppet, Furi and Zommer) they can create, name and nurture. Once their pet has been customized, players can navigate their way around Monstro City, take daily puzzle challenges to earn 'Rox' (a virtual currency), play games, personalize their room and communicate with other users in a safe environment (most of the time). Following its online success, Moshi Monsters has expanded commercially with physical products, including toys, Moshi Monsters Magazine (the number-one selling kids' magazine in the UK in 2011), a best-selling DS video game, a number 4 music album, books, membership cards, bath soap, chocolate calendars, trading cards, figures of many Moshlings, mobile games, and a Moshi Monsters feature film. In December 2012, eight Moshi Monster toys were included in McDonald's Happy Meals in the United States and Canada.
  • 3.5K
  • 30 Nov 2022
Topic Review
Computer-Vision-Based Water Level Measurement
Water level measurement is an important component of hydrological monitoring and water resources management. Information such as runoff, water supply volumes and flood discharge is usually calculated based on water level measurement. To alleviate the problems associated with manual and contact measurements, the computer-vision-based approaches rely on the automatic acquisition and analysis of water surface images. Images allow the capture of water surfaces without interruption to provide insight into the continuous change of water level. Computer vision can automatically acquire and understand the meaningful information in images, such as the scope of water surface area, water line, gauge characters, etc., to obtain faster recognition speed and more accurate and stable results than human in the water level measurement task.
  • 3.5K
  • 26 Sep 2023
Topic Review
Extraction Methods of Major Phytochemicals
Scientific studies have established a relationship between the consumption of phytochemicals such as carotenoids, polyphenols, isoprenoids, phytosterols, saponins, dietary fibers, polysaccharides, etc., with health benefits such as prevention of diabetes, obesity, cancer, cardiovascular diseases, etc. This has led to the popularization of phytochemicals. Foods containing phytochemicals as a constituent (functional foods) and the concentrated form of phytochemicals (nutraceuticals) are used as a preventive measure or cure for many diseases. The health benefits of these phytochemicals depend on their purity and structural stability. The yield, purity, and structural stability of extracted phytochemicals depend on the matrix in which the phytochemical is present, the method of extraction, the solvent used, the temperature, and the time of extraction.
  • 3.5K
  • 23 Feb 2023
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