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Topic Review
Frying Technology and Starchy Food
Frying is commonly used by consumers, restaurants, and industries around the globe to cook and process foods. Compared to other food processing methods, frying has several potential advantages, including reduced processing times and the creation of foods with desirable sensory attributes. Frying is often used to prepare starchy foods. After ingestion, the starch and fat in these foods are hydrolyzed by enzymes in the human digestive tract, thereby providing an important source of energy (glucose and fatty acids) for the human body. Conversely, overconsumption of fried starchy foods can induce overweight, obesity, and other chronic diseases. Moreover, frying can generate toxic reaction products that can damage people’s health. Consequently, there is interest in developing alternative frying technologies that reduce the levels of nutritionally undesirable components in fried foods, such as vacuum, microwave, air, and radiant frying methods.
  • 3.5K
  • 25 Aug 2021
Topic Review
Learning to Read
Learning to read is the acquisition and practice of the skills necessary to understand the meaning behind printed words. For a fairly good reader, the skill of reading should feel simple, effortless, and automatic. However, the process of learning to read is complex and builds on cognitive, linguistic, and social skills developed from a very early age. As one of the four core language skills (reading, writing, listening and speaking), reading is vital to gaining a command of the spoken language.
  • 3.5K
  • 03 Nov 2022
Topic Review
Medical Thermometer
A medical thermometer (also called clinical thermometer) is used for measuring human or animal body temperature. The tip of the thermometer is inserted into the mouth under the tongue (oral or sub-lingual temperature), under the armpit (axillary temperature), into the rectum via the anus (rectal temperature), into the ear (tympanic temperature), or on the forehead (temporal temperature).
  • 3.5K
  • 04 Nov 2022
Topic Review
The Sub-Saharan African Food Security Situation
All around the world, inequalities persist in the complex web of social, economic, and ecological factors that mediate food security outcomes at different human and institutional scales. There have been rapid and continuous improvements in agricultural productivity and better food security in many regions of the world due to an expansion in crop area, irrigation, and supportive policy and institutional initiatives. However, in Sub-Saharan Africa, the situation is inverted. Statistics show that food insecurity has risen since 2015 in Sub-Saharan African countries, and the situation has worsened owing to the Ukraine conflict and the ongoing implications of the COVID-19 threat.
  • 3.5K
  • 30 Nov 2022
Topic Review
Natural compounds for wood protection
Natural compounds for wood protection against fungi - all natural substances (or their mixtures) of plant or animal origin with proven antifungal activity and possibility to be applied into wood structure or on its surface to protect wood against wood decaying fungi, blue stain and mold, e.g. essential oils, tannins, wood extractives, alkaloids, propolis or chitosan.
  • 3.5K
  • 02 May 2021
Topic Review
Pocket-Sized Computer
Pocket-sized computer describes the post-programmable calculator / pre-smartphone pocket-sized portable-office hardware devices that included the earlier DOS-based palmtops and subsequent Windows-CE handhelds, as well as a few other terms, primarily covering the 1980s through 2007. Sometimes called Pocket-sized computing devices, they were a series of internally different devices, and included Handheld ("Pocket-sized handheld computing device"), and the earlier-introduced Palmtop ("Pocket-sized palmtop computing device") and "pocket-sized palmtop computer." The New York Times used the term "palmtop/handheld." The media called "the first computer that fits in your palm and weighs less than a pound" and its early day competitors a palmtop. Although the word "handheld" was used before Microsoft's 1996 introduction of Windows CE, a lawsuit by Palm, Inc pushed Microsoft's use of the new term Handheld PC. By 2007, the iPhone began to replace prior portable office devices, and by a decade later there were indications that "SmartGlasses" might be their replacement.
  • 3.5K
  • 28 Nov 2022
Topic Review
Electrical Conductivity of Nanoparticle-Enhanced Fluids
Research on nanoparticle-enhanced fluids’ electrical conductivity is at its beginning at this moment and the augmentation mechanisms are not fully understood. Basically, the mechanisms for increasing the electrical conductivity are described as electric double layer influence and increased particles’ conductance. Another idea that has resulted from state of the art is that the stability of nanofluids can be described with the help of electrical conductivity tests, but more coordinated research is needed. Concluding, this analysis has shown that a lot of research work is needed in the field of nanofluids’ electrical characterization and specific applications.
  • 3.5K
  • 23 Oct 2020
Topic Review
Environmental Impact of Waste Wood Ash
Waste wood ash (WWA) is used with other waste materials in geopolymer production and is found in pulp and paper, wood-burning industrial facilities, and wood-fired plants. 
  • 3.5K
  • 15 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
Structure and Function of Microbial Lipases
Lipases or triacylglycerol acyl hydrolases (EC 3.1.1.3) are ubiquitous in all realms of life. In nature, they are mainly characterized by catalyzing the hydrolysis of triglycerides and long-chain partial glycerides, releasing fatty acids, monoglycerides and glycerol. These enzymes constitute a key link in the cellular processes related to the absorption, release and metabolism of fats, since its substrates and derivatives are the most abundant lipids in cells. On the other hand, some lipases have also been attributed functions as defense enzymes or as virulence factors.  The main aspects of the structure–function of microbial lipases, reviewed more extensively in other articles, will be summarized in a general way, but, here, emphasis will be placed on aspects to be discussed in later sections such as their immobilization and applications in reactions of interest in the production of compounds related to APIs.
  • 3.5K
  • 21 Sep 2022
Topic Review
Sound Card
A sound card (also known as an audio card) is an internal expansion card that provides input and output of audio signals to and from a computer under the control of computer programs. The term sound card is also applied to external audio interfaces used for professional audio applications. Sound functionality can also be integrated onto the motherboard, using components similar to those found on plug-in cards. The integrated sound system is often still referred to as a sound card. Sound processing hardware is also present on modern video cards with HDMI to output sound along with the video using that connector; previously they used a S/PDIF connection to the motherboard or sound card. Typical uses of sound cards or sound card functionality include providing the audio component for multimedia applications such as music composition, editing video or audio, presentation, education and entertainment (games) and video projection. Sound cards are also used for computer-based communication such as voice over IP and teleconferencing.
  • 3.5K
  • 04 Nov 2022
Topic Review
Gauss' Method
In orbital mechanics (subfield of celestial mechanics), Gauss's method is used for preliminary orbit determination from at least three observations (more observations increases the accuracy of the determined orbit) of the orbiting body of interest at three different times. The required information are the times of observations, the position vectors of the observation points (in Equatorial Coordinate System), the direction cosine vector of the orbiting body from the observation points (from Topocentric Equatorial Coordinate System) and general physical data. Carl Friedrich Gauss developed important mathematical techniques (summed up in Gauss's methods) which were specifically used to determine the orbit of Ceres. The method shown following is the orbit determination of an orbiting body about the focal body where the observations were taken from, whereas the method for determining Ceres' orbit requires a bit more effort because the observations were taken from Earth while Ceres orbits the Sun.
  • 3.5K
  • 10 Nov 2022
Topic Review
Capybara (Hydrochoerus hydrochaeris)
The capybara (Hydrochoerus hydrochaeris) is a large, semi-aquatic mammal native to South America, recognized for its sociable behavior, robust physical form, and distinctive appearance. As the largest living rodent species, the capybara typically inhabits wetlands, riverbanks, and grasslands throughout the continent, ranging from Colombia and Venezuela to Argentina and Uruguay. It plays a significant ecological role in its native habitat and is closely associated with freshwater environments due to its need for access to water for survival and feeding. The capybara has garnered attention in recent years due to its distinctive social structure and behaviors, as well as its relatively calm disposition when interacting with humans and other species.
  • 3.5K
  • 08 Jul 2025
Topic Review
Models for Predicting Material Durability and Service Lifetime
Substantial gains and savings of resources of time and money can be gained through the use of modelling and simulation to understand material system performance. Since for development of the new materials validation is expensive and time-consuming, the bottleneck is time and funding—modelling might be the way to replace testing programs, which would be beneficial for providing new innovative materials faster to the market.
  • 3.5K
  • 25 Mar 2022
Topic Review
Sesame
Sesame (Sesamum indicum L.) is an important oilseed crop with well-developed value chains. It is Ethiopia’s most valuable export commodity after coffee (Coffea arabica L.), contributing to socioeconomic development. The productivity of the crop is low and stagnant in Ethiopia and other major sesame growing regions in sub-Saharan Africa (<0.6 t/ha) due to a multitude of production constraints. The low yield of sesame is attributable to a lack of high-yielding and well-adapted varieties, susceptibility to capsule shattering, the prevalence of biotic and abiotic stresses, and a lack of modern production technologies such as optimal agronomic managing practices, row planters, harvesters, and storage facilities.
  • 3.5K
  • 17 Jan 2022
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
Operating Principles of Fiber Bragg Grating Sensors
Fiber Bragg gratings (FBG) sensors are increasingly commercially available and are, one of the most popular sensors from the fiber optic sensing family, having found use in a variety of industrial and research applications. A conventional FBG sensor is made up of a specially fabricated small and flexible segment imprinted into the core of a single-mode optical fiber.
  • 3.5K
  • 14 Dec 2022
Topic Review
Sustainable Water Resources Management in Saudi Arabia
Saudi Arabia is one of the most water-scarce nations in the world, with a huge demand-supply gap, and the situation is expected to worsen due to climate change. Conventional surface water resources are limited, while nonrenewable groundwater sources are depleted. To build a more resilient and sustainable water sector, the production of non-conventional water resources, specifically desalinated seawater and treated domestic wastewater, has steadily increased in recent years. As the country lacks perennial water resources, such as rivers or water bodies, it relies mainly on nonrenewable groundwater and desalinated water to meet its daily requirements. Although the government is attempting to regulate the agricultural sector, water consumption in agriculture remains relatively high. It presents an environmental challenge due to its heavy reliance on non-renewable groundwater resources. The anticipated increase in temperature and highly uncertain changes in the rainfall patterns in Saudi Arabia could lead to greater uncertainty when attempting to develop effective water resource management plans.
  • 3.5K
  • 22 Dec 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
Process of Apoptosis
The term “Apoptosis” originates from Greek, which means the shedding of leaves from trees in autumn or the falling of petals from flowers. Apoptosis was firstly utilized by Kerr, Wyllie, and Currie in 1972 for explaining a morphologically discrete way of cell death. However, multiple concepts of apoptosis were precisely explained several years back. The main concept of apoptosis emerged from the knowledge of the process of programmed cell death that takes place in the developmental cycle of Caenorhabditis elegans.
  • 3.5K
  • 05 May 2022
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