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Topic Review
Saturn V Instrument Unit
The Saturn V Instrument Unit is a ring-shaped structure fitted to the top of the Saturn V rocket's third stage (S-IVB) and the Saturn IB's second stage (also an S-IVB). It was immediately below the SLA (Spacecraft/Lunar Module Adapter) panels that contained the Lunar Module. The Instrument Unit contains the guidance system for the Saturn V rocket. Some of the electronics contained within the Instrument Unit are a digital computer, analog flight control computer, emergency detection system, inertial guidance platform, control accelerometers and control rate gyros. The instrument unit (IU) for Saturn V was designed by NASA at Marshall Space Flight Center (MSFC) and was developed from the Saturn I IU. NASA's contractor to construct the Saturn V Instrument Unit was International Business Machines (IBM). One of the unused Instrument Units is currently on display at the Steven F. Udvar-Hazy Center in Chantilly, Virginia. The plaque for the Unit has the following inscription: The Saturn V rocket, which sent astronauts to the Moon, used inertial guidance, a self-contained system that guided the rocket's trajectory. The rocket booster had a guidance system separate from those on the command and lunar modules. It was contained in an instrument unit like this one, a ring located between the rocket's third stage and the command and lunar modules. The ring contained the basic guidance system components—a stable platform, accelerometers, a digital computer, and control electronics—as well as radar, telemetry, and other units. The instrument unit's stable platform was based on an experimental unit for the German V-2 rocket of World War II. The Bendix Corporation produced the platform, while IBM designed and built the unit's digital computer.
  • 1.9K
  • 06 Dec 2022
Topic Review
Role of Hydrochar for Multipurpose Applications
Hydrothermal carbonization converts high-moisture waste biomass into a valuable hydrochar unlocking multiple applications 
  • 1.9K
  • 17 Jan 2023
Topic Review
Wind Energy based on Triboelectric Nanogenerators
The utilization of various distributed energy is becoming a prominent research topic due to the rapid development of the Internet of Things and wireless condition monitoring systems. Among the various distributed energy sources, wind energy has the advantages of being widely distributed, renewable and pollution-free, and is a very promising mechanical energy for power supply. Traditional wind energy harvesting methods based on electromagnetic and piezoelectric effects have issues with complex structure, large size, severe mechanical structures, and high installation costs. The low frequency and irregular nature of ambient mechanical energy makes these methods generally inefficient and inevitably hinders the further exploitation of wind energy. The triboelectric nanogenerators (TENGs) based on frictional charging and electrostatic effects can also be used for wind power generation and are increasingly favored by researchers as TENGs are easier to be miniaturized and assembled, and can realize large-scale manufacturing in comparison.
  • 1.9K
  • 28 Sep 2022
Topic Review
Cobra Venom
Cobras (genus Naja) are widely distributed over Asia and Africa, and cobra envenomation is responsible for a large number of mortality and morbidity on these continents. Like other elapid venoms, cobra venoms are neurotoxic in nature; however, they also exhibit local cytotoxic effects at the envenomed site, and the extent of cytotoxicity may vary from species to species. Cobra venoms are predominated by the non-enzymatic three-finger toxin family which constitutes about 60-75% of the total venom. Cytotoxins (CTXs), an essential class of the non-enzymatic three-finger toxin family, are ubiquitously present in cobra venoms. These low-molecular-mass toxins, contributing to about 40 to 60% of the cobra venom proteome, play a significant role in cobra venom-induced toxicity, more prominently in dermonecrosis (local effects).
  • 1.9K
  • 12 Dec 2022
Topic Review
The BIANCA Biophysical Model
Cancer ion therapy is constantly growing, thanks to its increased precision and, for heavy ions, its increased biological effectiveness (RBE) with respect to conventional photon therapy. The complex dependence of RBE on many factors demands for biophysical modelling. Up to now only the Local Effect Model (LEM), the Microdosimetric Kinetic Model (MKM) and the “mixed-beam” model are used in clinics. In this work the BIANCA biophysical model, after extensive benchmarking in vitro, was applied to develop a database predicting cell survival for different ions, energies and doses. Following interface with the FLUKA Monte Carlo transport code, for the first time BIANCA was benchmarked against in vivo data obtained by C-ion or proton irradiation of the rat spinal cord. The latter is a well-established model for CNS (Central Nervous System) late effects, which in turn are the main dose-limiting factor for head-and-neck tumors. Furthermore, these data have been considered to validate the LEM version applied in clinics. Although further benchmarking is desirable, the agreement between simulations and data suggests that BIANCA can predict RBE for C-ion or proton treatment of head-and-neck tumors. In particular, the agreement with proton data may be relevant if the current assumption of a constant proton RBE of 1.1 is revised. This work provides the bases for future benchmarking against patient data, as well as the development of other databases for specific tumor types and/or normal tissues.
  • 1.9K
  • 02 Nov 2020
Topic Review
Tetrahydrofuran Biodegradation
Tetrahydrofuran (THF) is widely used as a precursor for polymer syntheses and a versatile solvent in industries. THF is an environmental hazard and carcinogenic to humans. We characterized the THF degradation potential of a number of THF-degrading bacteria reported before and a new isolated filamentous fungus Pseudallescheria boydii ZM01. Two different microbial THF degradation pathways have been proposed here. In addition, The initial key metabolic intermediate 2-hydroxytetrahydrofuran was detected and identified by gas chromatography (GC) analyses for the first time during the THF degradation process.
  • 1.9K
  • 10 Nov 2020
Topic Review
16p12.2 Microdeletion
16p12.2 microdeletion is a chromosomal change in which a small amount of genetic material on chromosome 16 is deleted. The deletion occurs on the short (p) arm of the chromosome at a location designated p12.2. Common characteristics that have been described in people with a 16p12.2 microdeletion include developmental delay, delayed speech, intellectual disability that ranges from mild to profound, weak muscle tone (hypotonia), slow growth resulting in short stature, an usually small head (microcephaly), malformations of the heart, recurrent seizures (epilepsy), and psychiatric and behavioral problems.
  • 1.9K
  • 23 Dec 2020
Topic Review
The Seed Quality Assurance Regulations in Soybean Production
Soybean is an important and valuable crop for global food and feed supply, providing high-quality nutrition. Globally, five countries—namely Brazil, the USA, Argentina, China and India—have dominated soybean production for many years. 
  • 1.9K
  • 10 May 2022
Topic Review
Water Aeration
Water aeration is the process of increasing or maintaining the oxygen saturation of water in both natural and artificial environments. Aeration techniques are commonly used in pond, lake, and reservoir management to address low oxygen levels or algal blooms.
  • 1.9K
  • 21 Oct 2022
Topic Review
Denormal Number
In computer science, subnormal numbers are the subset of denormalized numbers (sometimes called denormals) that fill the underflow gap around zero in floating-point arithmetic. Any non-zero number with magnitude smaller than the smallest normal number is subnormal. In a normal floating-point value, there are no leading zeros in the significand or mantissa; rather, leading zeros are removed by adjusting the exponent (for example, the number 0.0123 would be written as 1.23 × 10−2). Conversely, a denormalized floating point value has a significand with a leading digit of zero. Of these, the subnormal numbers represent values which if normalized would have exponents below the smallest representable exponent (the exponent having a limited range). The significand (or mantissa) of an IEEE floating-point number is the part of a floating-point number that represents the significant digits. For a positive normalised number it can be represented as m0.m1m2m3...mp−2mp−1 (where m represents a significant digit, and p is the precision) with non-zero m0. Notice that for a binary radix, the leading binary digit is always 1. In a subnormal number, since the exponent is the least that it can be, zero is the leading significant digit (0.m1m2m3...mp−2mp−1), allowing the representation of numbers closer to zero than the smallest normal number. A floating-point number may be recognized as subnormal whenever its exponent is the least value possible. By filling the underflow gap like this, significant digits are lost, but not as abruptly as when using the flush to zero on underflow approach (discarding all significant digits when underflow is reached). Hence the production of a subnormal number is sometimes called gradual underflow because it allows a calculation to lose precision slowly when the result is small. In IEEE 754-2008, denormal numbers are renamed subnormal numbers and are supported in both binary and decimal formats. In binary interchange formats, subnormal numbers are encoded with a biased exponent of 0, but are interpreted with the value of the smallest allowed exponent, which is one greater (i.e., as if it were encoded as a 1). In decimal interchange formats they require no special encoding because the format supports unnormalized numbers directly. Mathematically speaking, the normalized floating-point numbers of a given sign are roughly logarithmically spaced, and as such any finite-sized normal float cannot include zero. The subnormal floats are a linearly spaced set of values, which span the gap between the negative and positive normal floats.
  • 1.9K
  • 08 Nov 2022
Topic Review
Basic Principles of Bioprocess Monitoring and Viability Determination
Bioprocesses involve multiple steps, including upstream processing, downstream processing and product formulation. Each of these steps must be monitored and regulated precisely, which requires suitable sensors that meet specific demands. Both the process itself and the process monitoring can be arranged differently. Likewise, this applies to the determination of viability, with each method possessing advantages and disadvantages.
  • 1.9K
  • 08 Feb 2023
Topic Review
Traditional African Medicine
Traditional African medicine is a range of traditional medicine disciplines involving indigenous herbalism and African spirituality, typically including diviners, midwives, and herbalists. Practitioners of traditional African medicine claim to be able to cure a variety of diverse conditions including cancer, psychiatric disorders, high blood pressure, cholera, most venereal diseases, epilepsy, asthma, eczema, fever, anxiety, depression, benign prostatic hyperplasia, urinary tract infections, gout, and healing of wounds and burns and even Ebola. Diagnosis is reached through spiritual means and a treatment is prescribed, usually consisting of a herbal remedy that is considered to have not only healing abilities but also symbolic and spiritual significance. Traditional African medicine, with its belief that illness is not derived from chance occurrences, but through spiritual or social imbalance, differs greatly from modern scientific medicine, which is technically and analytically based. In the 21st century, modern pharmaceuticals and medical procedures remain inaccessible to large numbers of African people due to their relatively high cost and concentration of health facilities in urban centres. Traditional medicine was the dominant medical system for millions of people in Africa prior the arrival of the Europeans, who introduced western-based medicine, which was a noticeable turning point in the history of this tradition and culture. Herbal medicines in Africa are generally not adequately researched, and are weakly regulated. There is a lack of the detailed documentation of the traditional knowledge, which is generally transferred orally. Serious adverse effects can result from mis-identification or misuse of healing plants. The geographical reach of this article is Sub-Saharan Africa. Though, of course neighbouring medical traditions influenced traditional African medicine.
  • 1.9K
  • 04 Nov 2022
Topic Review
Architectures of Polyacrylic Acid
Polyacrylic acid (PAA) is a non-toxic, biocompatible, and biodegradable polymer that gained lots of interest in recent years. PAA nano-derivatives can be obtained by chemical modification of carboxyl groups with superior chemical properties in comparison to unmodified PAA.
  • 1.9K
  • 01 Apr 2022
Topic Review
Hepatitis E Virus
Hepatitis E virus (HEV) (family Hepeviridae) is one of the most common human pathogens, causing acute hepatitis and an increasingly recognized etiological agent in chronic hepatitis and extrahepatic manifestations. Not only the members of the species Orthohepevirus A  (HEV-A) pathogenic to humans but a genetically highly divergent rat origin hepevirus (HEV-C1) in species Orthohepevirus C (HEV-C) is also able to cause zoonotic infection and symptomatic disease (hepatitis) in humans.
  • 1.9K
  • 29 Oct 2020
Topic Review
The LPA3 Receptor
Lysophosphatidic acid receptor 3 (LPA3) is implicated in different physiological and pathological functions through activation of different signal pathways, the result of the regulation process of this receptor. The knowledge of regulating LPA3 could be a crucial element for defined their roles in health and disease.
  • 1.9K
  • 09 Jul 2021
Topic Review
Alarming Systems for Hazardous Gases and Volatile Chemicals
The leakage of hazardous gases and chemical vapors is considered one of the dangerous accidents that can occur in laboratories, workshops, warehouses, and industrial sites that use or store these substances. The early detection and alarming of hazardous gases and volatile chemicals are significant to keep the safety conditions for the people and life forms who are work in and live around these places.
  • 1.9K
  • 15 Dec 2021
Topic Review
High Performance Polymer Composites
Summarize data on the structure, mechanical and tribological properties, and wear patterns of composites based on high-performance polymers (HPPs) intended for use in friction units. The three key sections, divided according to the tribological contact schemes regardless of the polymer matrix. In the second part, the analysis of composites is carried out in point contacts. The third section is devoted to the results of studies of HPP-based composites in linear ones. The fourth section summarizes information on flat contacts. Particular attention is paid to the formation of transfer films (TFs) in the contacts and their influence on the tribological patterns of the studied rubbing materials.
  • 1.9K
  • 16 Mar 2022
Topic Review
Nosler Proprietary Cartridges
Nosler produces various high performance hollow point and soft point hunting bullets.
  • 1.9K
  • 02 Nov 2022
Topic Review
Photoelectrochemical Reduction of CO2
Photoelectrochemical reduction of CO2 is a chemical process whereby carbon dioxide is reduced to carbon monoxide or hydrocarbons by the energy of incident light. This process needs to be catalyzed either homogeneously or heterogeneously in order to proceed, and current research is aimed at developing these catalysts, most of which are semiconducting materials. Semiconducting catalysts provide favourable electron transfer kinetics. The feasibility of this chemical reaction was first theorised by Giacomo Luigi Ciamician, an Italian photochemist. Already in 1912 he stated that "By  using  suitable catalyzers,  it  should  be  possible  to  transform  the mixture  of  water  and  carbon dioxide into oxygen and methane, or to cause other endo-energetic processes." Motivation for research in this area is strong due to the current attention to atmospheric carbon dioxide as the reduction of carbon dioxide would be one route for removal and sequestration. Furthermore, the reduced species may prove to be a valuable feedstock for other processes. If the incident light utilized is solar in nature then this process also potentially represents energy routes which combine renewable energy with CO2 reduction.
  • 1.9K
  • 02 Nov 2022
Topic Review
Global Buddhist Network
The Global Buddhist Network (GBN), previously known as the Dhammakaya Media Channel (DMC) is a Thai online television channel concerned with Buddhism. The channel's taglines were "The secrets of life revealed" and "The only one", but these were later replaced by "Channel for the path to the cessation of suffering and attainment of Dhamma". The channel features many types of programs with Buddhist content, and has programs in several languages. The channel started in 2002, as a means to reach remote provinces in Thailand. Controversially, the channel made international headlines in 2012 when it featured a teaching on the afterlife of Steve Jobs. On 26 December 2016, Thai authorities withdrew the permit for the satellite channel permanently, during the legal investigations into the temple by the Thai junta. In April 2017, it was reported, however, that the channel's programming had continued, but broadcast through the Internet only. In its online format, the channel has been renamed Global Buddhist Network.
  • 1.9K
  • 03 Nov 2022
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