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Topic Review
Luch (Satellite)
The Luch (Russian: Луч; lit. Ray) Satellite Data Relay Network (SDRN), also referred to as Altair and Gelios, is a series of geosynchronous Russian relay satellites, used to transmit live TV images, communications and other telemetry from the Soviet/Russian space station Mir, the Russian Orbital Segment (ROS) of the International Space Station and other orbital spacecraft to the Earth, in a manner similar to that of the US Tracking and Data Relay Satellite System.
  • 2.0K
  • 21 Nov 2022
Topic Review
IBM POWER Microprocessors
IBM has a series of high performance microprocessors called POWER followed by a number designating generation, i.e. POWER1, POWER2, POWER3 and so forth up to the latest POWER9. These processors have been used by IBM in their RS/6000, AS/400, pSeries, iSeries, System p, System i and Power Systems line of servers and supercomputers. They have also been used in data storage devices by IBM and by other server manufacturers like Bull and Hitachi. The name "POWER" was originally presented as an acronym for "Performance Optimization With Enhanced RISC". The POWERn family of processors were developed in the late 1980s and are still in active development nearly 30 years later. In the beginning, they utilized the POWER instruction set architecture (ISA), but that evolved into PowerPC in later generations and then to Power Architecture, so modern POWER processors do not use the POWER ISA, they use the Power ISA.
  • 2.0K
  • 23 Nov 2022
Topic Review
Battery Management System
Renewable energy penetration and distributed generation are key for the transition towards more sustainable societies, but they impose a substantial challenge in terms of matching generation with demand due to the intermittent and unpredictable nature of some of these renewable energy sources. Thus, the role of energy storage in today’s and future electricity markets is undisputed. Batteries stand out among the different alternatives for energy storage.
  • 2.0K
  • 05 Sep 2023
Topic Review
Iodine Deficiency
Iodine deficiency is a global issue and affects around 2 billion people worldwide, with pregnant women as a high-risk group. Iodine-deficiency prevention began in the 20th century and started with global salt iodination programmes, which aimed to improve the iodine intake status globally.
  • 2.0K
  • 19 Feb 2021
Topic Review
Alpha 1-Antitrypsin Deficiency
Alpha-1 antitrypsin deficiency (A1AD or AATD) is a genetic disorder that may result in lung disease or liver disease. Onset of lung problems is typically between 20 and 50 years old. This may result in shortness of breath, wheezing, or an increased risk of lung infections. Complications may include COPD, cirrhosis, neonatal jaundice, or panniculitis. A1AD is due to a mutation in the SERPINA1 gene that results in not enough alpha-1 antitrypsin (A1AT). Risk factors for lung disease include cigarette smoking and environmental dust. The underlying mechanism involves unblocked neutrophil elastase and build up of abnormal A1AT in the liver. It is autosomal co-dominant, meaning that one defective allele tends to result in milder disease than two defective alleles. The diagnosis is suspected based on symptoms and confirmed by blood tests or genetic tests. Treatment of lung disease may include bronchodilators, inhaled steroids, and when infections occur antibiotics. Intravenous infusions of the A1AT protein or in severe disease lung transplantation may also be recommended. In those with severe liver disease liver transplantation may be an option. Avoiding smoking is recommended. Vaccination for influenza, pneumococcus, and hepatitis is also recommended. Life expectancy among those who smoke is 50 years old while among those who do not smoke it is almost normal. The condition affects about 1 in 2,500 people of Europeans descent. Severe deficiency occurs in about 1 in 5,000. In Asians it is uncommon. About 3% of people with COPD are believed to have the condition. Alpha-1 antitrypsin deficiency was first described in the 1960s.
  • 2.0K
  • 11 Nov 2022
Topic Review
Adder (Electronics)
An adder, or summer, is a digital circuit that performs addition of numbers. In many computers and other kinds of processors adders are used in the arithmetic logic units (ALUs). They are also used in other parts of the processor, where they are used to calculate addresses, table indices, increment and decrement operators and similar operations. Although adders can be constructed for many number representations, such as binary-coded decimal or excess-3, the most common adders operate on binary numbers. In cases where two's complement or ones' complement is being used to represent negative numbers, it is trivial to modify an adder into an adder–subtractor. Other signed number representations require more logic around the basic adder.
  • 2.0K
  • 24 Nov 2022
Topic Review
Positronium as a Probe of Polymer Free Volume
Positron annihilation lifetime spectroscopy (PALS) is a valuable technique to investigate defects in solids, such as vacancy clusters and grain boundaries in metals and alloys, as well as lattice imperfections in semiconductors. In the case of polymers, PALS is able to give information on the holes forming the free volume; this quantity, is correlated to important mechanical, thermal, and transport properties of polymers. PALS supplies a quantitative measure of the free volume by probing the corresponding sub-nanometric holes. The system used is positronium (Ps), an unstable atom formed by a positron and an electron, whose lifetime can be related to the typical size of the holes.
  • 2.0K
  • 18 Sep 2023
Topic Review
Lemon Verbena (Aloysia citrodora)
Aloysia citrodora (Verbenaceae), an acknowledged medicinal plant, is traditionally used to treat various diseases, including bronchitis, insomnia, anxiety, digestive, and heart problems.
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  • 21 Mar 2022
Topic Review
Drone Forensics
Unmanned aerial vehicles (UAVs) are adaptable and rapid mobile boards that can be applied to several purposes, especially in smart cities. These involve traffic observation, environmental monitoring, and public safety. The need to realize effective drone forensic processes has mainly been reinforced by drone-based evidence. Drone-based evidence collection and preservation entails accumulating and collecting digital evidence from the drone of the victim for subsequent analysis and presentation.
  • 2.0K
  • 22 Sep 2022
Topic Review
The Sigma-2 Receptor
The sigma-2 receptor (S2R), encoded by TMEM97, is expressed in brain and retinal cells, and regulates cell functions via its co-receptor progesterone receptor membrane component 1 (PGRMC1), and through other protein–protein interactions. S2R modulates key pathways, including autophagy, trafficking, oxidative stress, and amyloid-β and α-synuclein toxicity, involved in age-related degenerative diseases of the central nervous system. Furthermore, S2R modulation can ameliorate functional deficits in cell-based and animal models of neurodegenerative disease.
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  • 06 Apr 2023
Topic Review
Compounds of Lead
Compounds of lead exist in two main oxidation states: +2 and +4. The former is more common. Inorganic lead(IV) compounds are typically strong oxidants or exist only in highly acidic solutions.
  • 2.0K
  • 14 Nov 2022
Topic Review
Cistus ladanifer as a Potential Feedstock for Biorefineries
Cistus ladanifer (rockrose) is a widespread shrub species in the Mediterranean region well known due to its production of labdanum gum, especially in the hot season. Its leaves and branches can be subjected to different extraction and distillation processes to produce various types of extracts. The natural extracts of C. ladanifer have several applications, especially in the perfumery and cosmetics sector. C. ladanifer extracts, in addition to presenting interesting odoriferous properties, are also known for their bioactive properties, such as antioxidant and antimicrobial. The use of this species in animal feed or phytostabilisation of mining areas has also been successfully applied. Furthermore, the lignin and polysaccharides that are the major fractions from Cistus residues can be relevant sources of high-value products in a biorefinery framework.
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  • 02 Feb 2023
Topic Review
Götz Prosthesis Reconstructions
In this entry, the 3D CAD reconstructions and 3D multi-material polymer replica printings of knight Götz von Berlichingen´s first "Iron Hand", which were developed in the last few years at Offenburg University, are presented. Even by today's standards, the first “Iron Hand”–as could be shown in the replicas–demonstrates sophisticated mechanics and well thought-out functionality and still offers inspiration and food for discussion when it comes to the question of an artificial prosthetic replacement for a hand. 
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  • 14 Jan 2021
Topic Review
Digital Transformation(DX): Implications for Business
The origin and development of the term “digital transformation” can be examined based on Germany’s Industry 4.0, the Fourth Industrial Revolution, and the development of the digital economy. First, Industry 4.0 was a policy adopted in November 2011 as a strategy for information and communications as a part of Germany’s High-Tech Strategy 2020. Its goal is to achieve innovation in the manufacturing business [6], and according to Deloitte, the goal of this policy encompasses not only the development of specific technology but also a paradigm shift in the manufacturing business.
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  • 23 Sep 2021
Topic Review
Diaporthe citri
Citrus melanose is a fungal disease caused by Diaporthe citri F.A. Wolf. It is found in various citrus-growing locations across the world. The host range of D. citri is limited to plants of the Citrus genus. The most economically important hosts are Citrus reticulata (mandarin), C. sinensis (sweet orange), C. grandis or C. maxima (pumelo), and C. paradisi (grapefruit). In the life cycle of D. citri throughout the citrus growing season, pycnidia can be seen in abundance on dead branches, especially after rain, with conidia appearing as slimy masses discharged from the dead twigs. Raindrops can transmit conidia to leaves, twigs, and fruits, resulting in disease dispersion throughout small distances. Persistent rains and warm climatic conditions generally favor disease onset and development. The melanose disease causes a decline in fruit quality, which lowers the value of fruits during marketing and exportation. High rainfall areas should avoid planting susceptible varieties.
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  • 04 Jul 2022
Topic Review
Nebra Sky Disk
The Nebra sky disk is a bronze disk of around 30 centimetres (11 3⁄4 in) diameter and a weight of 2.2 kilograms (4.9 lb), having a blue-green patina and inlaid with gold symbols. These symbols are interpreted generally as the Sun or full moon, a lunar crescent, and stars (including a cluster of seven stars interpreted as the Pleiades). Two golden arcs along the sides, interpreted to mark the angle between the solstices, were added later. A final addition was another arc at the bottom surrounded with multiple strokes (of uncertain meaning, variously interpreted as a solar barge with numerous oars, the Milky Way, or a rainbow). The disk has been attributed to a site in present-day Germany near Nebra, Saxony-Anhalt, and was originally dated by archaeologists to c. 1600 BCE. Researchers initially suggested the disk is an artifact of the Bronze Age Unetice culture, although a later dating to the Iron Age has been proposed as well. If its Bronze Age dating is accurate, the Nebra sky disk features the oldest concrete depiction of the cosmos yet known from anywhere in the world. In June 2013 it was included in the UNESCO Memory of the World Register and termed "one of the most important archaeological finds of the twentieth century."
  • 2.0K
  • 23 Nov 2022
Topic Review
Zinc Coating
Advanced high strength galvanized steel sheet has been one of the dominant materials of modern automotive panels because of its outstanding mechanical properties and corrosion resistance. The zinc coating thickness of hot dip galvanized steel sheet is only about 10–20μm, which is a discarded object on the macro level. However, it is obvious to damage and impact on stamping performance. Therefore, this work takes zinc coating as the research object and builds its mechanical constitutive model based on a nano-indentation test and dimensional analysis theory. We separated the zinc coating from the galvanized steel substrate and constructed a sandwich material model by introducing a cohesive layer to connect the zinc coating and the steel substrate. We obtained the interface binding energy between the zinc coating and the steel substrate through the nano-scratch test. The accuracy of the model is verified by the finite element analysis of hemispherical parts. We used the five-layers element model with 0 thickness cohesive layer to simulate the zinc coating damage of galvanized steel sheet. The hemispherical part drawing experiment is used to verify the feasibility of the finite element analysis results. The results demonstrate that it is more accurate to consider the finite element numerical simulation of the zinc coating, introducing the cohesive element to simulate damage between the coating and the substrate. Drawing depth, stamping force, and the strain of the numerical simulation are closer to the experimental results.
  • 2.0K
  • 01 Nov 2020
Topic Review
Aquatic Mosses as Adaptable Bio-Filters
Heavy metals (HMs) are released into the environment by many human activities and persist in water even after remediation. The efficient filtration of solubilized HMs is extremely difficult. Phytoremediation appears a convenient tool to remove HMs from polluted water, but it is limited by the choice of plants able to adapt to filtration of polluted water in terms of space and physiological needs. Biomasses are often preferred. Aquatic moss biomasses, thanks to gametophyte characteristics, can act as live filtering material. The potential for phytoremediation of Hypnales aquatic mosses has been poorly investigated compared to aquatic macrophytes. Their potential is usually indicated as a tool for bioindication and environmental monitoring more than for pollutant removal. When phytoremediation has been considered, insufficient attention has been paid to the adaptability of biomasses to different needs. In this study the heavy metal uptake of moss Taxiphyllum barbieri grown in two different light conditions, was tested with high concentrations of elements such as Pb, Cd, Zn, Cu, As, and Cr. This moss produces dense mats with few culture needs. The experimental design confirmed the capacity of the moss to accumulate HMs accordingly to their physiology and then demonstrated that a significant proportion of HMs was accumulated within a few hours. In addition to the biosorption effect, an evident contribution of the active simplastic mass can be evidenced. These reports of HM accumulation within short time intervals, show how this moss is particularly suitable as an adaptable bio-filter, representing a new opportunity for water eco-sustainable remediation.
  • 2.0K
  • 31 May 2021
Biography
Giacomo Mauro D’Ariano
Giacomo Mauro D’Ariano (born 11 May 1955) is an Italian quantum physicist. He is a professor of theoretical physics at the University of Pavia, where he is the leader of the QUIT (Quantum Information Theory) group.[1][2] He is a member of the Center of Photonic Communication and Computing at Northwestern University;[3] a member of the Istituto Lombardo Accademia di Scienze e Lettere; and a mem
  • 2.0K
  • 16 Nov 2022
Topic Review
TRPV1
Intracellular calcium (Ca2+) concentration ([Ca2+]i) is a key determinant of cell fate and is implicated in carcinogenesis. Membrane ion channels are structures through which ions enter or exit the cell, depending on the driving forces. The opening of transient receptor potential vanilloid 1 (TRPV1) ligand-gated ion channels facilitates transmembrane Ca2+ and Na+ entry, which modifies the delicate balance between apoptotic and proliferative signaling pathways. Proliferation is upregulated through two mechanisms: (1) ATP binding to the G-protein-coupled receptor P2Y2, commencing a kinase signaling cascade that activates the serine-threonine kinase Akt, and (2) the transactivation of the epidermal growth factor receptor (EGFR), leading to a series of protein signals that activate the extracellular signal-regulated kinases (ERK) 1/2. The TRPV1-apoptosis pathway involves Ca2+ influx and efflux between the cytosol, mitochondria, and endoplasmic reticulum (ER), the release of apoptosis-inducing factor (AIF) and cytochrome c from the mitochondria, caspase activation, and DNA fragmentation and condensation. While proliferative mechanisms are typically upregulated in cancerous tissues, shifting the balance to favor apoptosis could support anti-cancer therapies. TRPV1, through [Ca2+]i signaling, influences cancer cell fate; therefore, the modulation of the TRPV1-enforced proliferation–apoptosis balance is a promising avenue in developing anti-cancer therapies and overcoming cancer drug resistance. 
  • 2.0K
  • 09 Nov 2020
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