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Topic Review
Doping (Semiconductor)
In semiconductor production, doping is the intentional introduction of impurities into an intrinsic semiconductor for the purpose of modulating its electrical and optical and structural properties. The doped material is referred to as an extrinsic semiconductor. A semiconductor doped to such high levels that it acts more like a conductor than a semiconductor is referred to as a degenerate semiconductor. In the context of phosphors and scintillators, doping is better known as activation. Doping is also used to control the color in some pigments.
  • 3.2K
  • 08 Nov 2022
Topic Review
Energy Poverty
The term “energy poverty” usually refers to the lack of affordability or of access to basic energy services to meet one’s most common needs, such as lighting, cooking, heating and cooling.
  • 3.2K
  • 15 Oct 2021
Topic Review
Biodegradation of Polyethylene Terephthalate
Polyethylene terephthalate (PET) is a widely used plastic that is polymerized by terephthalic acid (TPA) and ethylene glycol (EG).
  • 3.2K
  • 30 Dec 2021
Topic Review
Chili Pepper Carotenoids: Nutraceutical Properties
Chili pepper is a prominent cultivated horticultural crop that is traditionally used for food seasoning and is applied for the treatment and prevention of multiple diseases. Its beneficial health properties are due to its abundance and variety of bioactive components, such as carotenoids, capsaicinoids, and vitamins. In particular, carotenoids have important nutraceutical properties, and several studies have focused on their potential in the prevention and treatment of human diseases.
  • 3.2K
  • 28 Sep 2021
Topic Review
Membrane Protein
Membrane proteins are polypeptides integrated into or associated with biological membranes. They are present at roughly equal weight to phospholipids in plasma membranes of cells, in outer membranes of bacteria, mitochondria, chloroplasts and in other organelles. Membrane proteins govern the active functions of membranes, such as transport, signalling, asymmetry and polarisation. Membrane proteins follow characteristic folding patterns and have hydrophobic domains that make them compatible with the amphipathic lipid biayers.
  • 3.2K
  • 24 Dec 2020
Topic Review
Nitrogen Turbine Engine
An ever-increasing demand for electrical power and soaring levels of energy consumption around the world have led to an energy crisis. Thus, this entry focuses on the conventional technologies against those of newer developments in electrical power generation such as using nitrogen generators. The nitrogen generator method is most appealing as it is a seemingly free energy already existing in nature. A nitrogen generator with a 5000 (Nm3/h) capacity has the potential to be used to analyze gas composition and the results are compared with the gas composition of a conventional steam turbine, which is used to pressurize 6000 (kWh) injection steam turbines. The magnetic bearing must be installed in both systems to modify all centrifuged systems which reduces all energy consumption in all systems by more than 50%. Artificial intelligence is used with the machine to analyze and control nitrogen gas flow to provide a more precise evaluation resulting in a more efficient technology. It should further be noted that the nitrogen turbine is superior to the steam turbine because it does not require the burning of fossil fuel to generate power. Hence, it is crucial to modify conventional technologies to improve energy sustainability and begin the long task of tackling environmental issues.
  • 3.2K
  • 12 Oct 2021
Topic Review
Logistic Handling of Deliveries at an LNG Terminal
LNG is a gas mixture of hydrocarbons in the following proportions: methane 87–99 mol%, ethane 0.1–5.5 mol%, propane 0–4 mol%, butane 0–2.5 mol%, nitrogen 0.02–1 mol%, and traces of sulfur (less than four ppmv) and CO2 (50 ppmv). There has been growing interest in fuel supply chains regarding transport safety and LNG reloading. This is due to the increasing consumption of this gas in the economy to create sustainable transport systems. Poland is in the phase of energy transformation, which increases the demand for this type of alternative fuel. For this reason, the number of logistic operations carried out by Polish sea terminals handling LNG deliveries is increasing.
  • 3.2K
  • 07 May 2022
Topic Review
Armoured Vehicle Royal Engineers
Armoured Vehicle Royal Engineers (AVRE), also known as Assault Vehicle Royal Engineers is the title given to a series of armoured military engineering vehicles operated by the Royal Engineers (RE) for the purpose of protecting engineers during frontline battlefield operations. In protecting engineers, the vehicles also became a mobile platform for a variety of engineering purposes, mounting large calibre weapons for demolition, carrying engineering stores, mine clearance explosives, a variety of deployable roadways, and modified engineering bridges for gaps that the related Armoured Ramp Carrier ("ARK") vehicles could not overcome.
  • 3.2K
  • 28 Oct 2022
Topic Review
The Complement System in the Central Nervous System
The functions of the complement system to both innate and adaptive immunity through opsonization, cell lysis, and inflammatory activities are well known. In contrast, the role of complement in the central nervous system (CNS) which extends beyond immunity, is only beginning to be recognized as important to neurodevelopment and neurodegeneration. In addition to protecting the brain against invasive pathogens, appropriate activation of the complement system is pivotal to the maintenance of normal brain function.
  • 3.2K
  • 28 Mar 2022
Topic Review
Lahar
A lahar ( /ˈlɑːhɑːr/, from Template:Lang-jv) is a violent type of mudflow or debris flow composed of a slurry of pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a river valley. Lahars are extremely destructive: they can flow tens of metres per second, they have been known to be up to 140 metres (460 ft) deep, and large flows tend to destroy any structures in their path. Notable lahars include those at Mount Pinatubo and Nevado del Ruiz, the latter of which killed thousands of people in the town of Armero.
  • 3.2K
  • 17 Oct 2022
Topic Review
Electrochemical Impedance Spectroscopy
Electrochemical impedance spectroscopy is finding increasing use in electrochemical sensors and biosensors, both in their characterisation, including during successive phases of sensor construction, and in application as a quantitative determination technique.
  • 3.2K
  • 28 Apr 2022
Topic Review
Tunneling and Blocking Oxides on Memory Cells
Flash memory is an electronic, non-volatile information storage device that can be electrically erased and reprogrammed. Ideally, the information stored in such a device should be preserved for long when the power is switched off. There are two flash memories designs at present: floating gate and charge trapping. Both of them work by storage of electrical charges in the space above the channel of the MOSFET. The charge storage volume of the flash cell, either poly-Si floating gate or charge trapping dielectric/dielectric stack is confined between blocking and tunnel oxides for electrical insulation from the gate electrode and Si substrate. Blocking and tunnelling oxides are important parts of the flash memory cells, as they affect retention, endurance and program/erase speed performance.
  • 3.2K
  • 20 Oct 2023
Topic Review
Bit Manipulation Instruction Sets
Bit Manipulation Instructions Sets (BMI sets) are extensions to the x86 instruction set architecture for microprocessors from Intel and AMD. The purpose of these instruction sets is to improve the speed of bit manipulation. All the instructions in these sets are non-SIMD and operate only on general-purpose registers. There are two sets published by Intel: BMI (here referred to as BMI1) and BMI2; they were both introduced with the Haswell microarchitecture. Another two sets were published by AMD: ABM (Advanced Bit Manipulation, which is also a subset of SSE4a implemented by Intel as part of SSE4.2 and BMI1), and TBM (Trailing Bit Manipulation, an extension introduced with Piledriver-based processors as an extension to BMI1, but dropped again in Zen-based processors).
  • 3.2K
  • 17 Oct 2022
Topic Review
Senescence
Plants not only may delay senescence until after they reproduce successfully, but they may also bring senescence time forward, in order to reproduce in favored conditions. It demonstrates that even though senescence is part of aging, it does not necessarily mean plants have to reach a certain age to senesce. Experiments using different aged plants have suggested that in interest of their final outcome and fitness, plants carefully weigh out environmental cues and transit to next developmental phase at proper time, even if that means transiting to terminal senescence phase earlier and shortening their lifespan.
  • 3.2K
  • 20 Feb 2021
Topic Review
Bioactive Compounds from Marine Sponges
Marine sponges are sessile invertebrates that can be found in temperate, polar and tropical regions. They are known to be major contributors of bioactive compounds, which are discovered in and extracted from the marine environment. The compounds extracted from these sponges are known to exhibit various bioactivities, such as antimicrobial, antitumor and general cytotoxicity.
  • 3.2K
  • 25 May 2021
Topic Review
Sleep in Declarative Memory Consolidation
There is ample evidence supporting a key role of sleep in memory consolidation. Thalamo-cortical and hippocampal-neocortical interactions allow the reconfiguration of synapses. Oscillatory and molecular changes are involved during sleep in memory consolidation and synaptic rescalling.
  • 3.2K
  • 27 Oct 2020
Topic Review
Nazirite
In the Hebrew Bible, a nazirite or nazarite is one who voluntarily took a vow described in Numbers 6:1–21. "Nazarite" comes from the Hebrew word נזיר nazir meaning "consecrated" or "separated". This vow required the person to: After following these requirements for a designated interval (which would be specified in the individual's vow), the person would immerse in a mikveh and make three offerings: a lamb as a burnt offering (olah), a ewe as a sin-offering (hatat), and a ram as a peace offering (shelamim), in addition to a basket of unleavened bread, grain offerings and drink offerings, which accompanied the peace offering. They would also shave their head in the outer courtyard of the Jerusalem Temple and then place the hair on the same fire as the peace offering. (Numbers 6:18) The nazirite is described as being "holy unto YHWH" (Numbers 6:8), yet at the same time must bring a sin offering. This has led to divergent approaches to the nazirite in the Talmud, and later authorities, with some viewing the nazirite as an ideal, and others viewing him as a sinner.
  • 3.2K
  • 27 Oct 2022
Biography
Murray Bookchin
Murray Bookchin (January 14, 1921 – July 30, 2006)[1] was an United States social theorist, author, orator, historian, and political philosopher. A pioneer in the ecology movement,[2] Bookchin formulated and developed the theory of social ecology and urban planning, within anarchist, libertarian socialist, and ecological thought. He was the author of two dozen books covering topics in politics
  • 3.2K
  • 30 Dec 2022
Topic Review
Application of GIS in Agriculture
GIS technology application in agriculture has gained prominence. The main GIS application areas identified included: crop yield estimation, soil fertility assessment, cropping patterns monitoring, drought assessment, pest and crop disease detection and management, precision agriculture, and fertilizer and weed management. GIS technology has the potential to enhance agriculture sustainability by integrating the spatial dimension of agriculture into agriculture policies. In addition, GIS's potential in promoting evidence-informed decision-making is growing. There is, however, a big gap in GIS application in sub-Saharan Africa. With the growing threat of climate change to agriculture and food security, there is an increased need for the integration of GIS in policy and decision-making in improving agriculture sustainability.
  • 3.2K
  • 09 Sep 2022
Topic Review
10q26 Deletion Syndrome
10q26 deletion syndrome is a condition that results from the loss (deletion) of a small piece of chromosome 10 in each cell. The deletion occurs on the long (q) arm of the chromosome at a position designated 10q26.
  • 3.2K
  • 26 Aug 2021
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