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Topic Review
Geopolymer Materials
The advancement of eco-friendly technology in the construction sector has been improving rapidly. As a result, multiple building materials were developed, enhanced, and proposed as replacements for some traditional materials. One notable example presents geopolymer as a substitute for ordinary Portland concrete (OPC). The manufacturing process of (OPC) generates CO2 emissions and a high energy demand, both of which contribute to ozone depletion and global warming. The implementation of geopolymer concrete (GPC) technology in the construction sector provides a path to more sustainable growth and a cleaner environment. This is due to geopolymer concrete’s ability to reduce environmental pollutants and reduce the construction industry’s carbon footprint. This is achieved through its unique composition, which typically involves industrial byproducts like fly ash or slag. These materials, rich in silicon and aluminum, react with alkaline solutions to form a binding gel, bypassing the need for the high-energy clinker production required in OPC. The use of such byproducts not only reduces CO2 emissions but also contributes to waste minimization. Additionally, geopolymer offers extra advantages compared to OPC, including improved mechanical strength, enhanced durability, and good stability in acidic and alkaline settings. Such properties make GPC particularly suitable for a range of construction environments, from industrial applications to infrastructure projects exposed to harsh conditions. 
  • 2.7K
  • 15 Dec 2023
Topic Review
Aerobic Granular Sludge
The aerobic granular sludge (AGS) method, which has been developed for several years, may represent an alternative to traditional technologies. One of the barriers to AGS deployment is the limited knowledge on the determinants and efficiency of the anaerobic digestion (AD) of AGS, as little research has been devoted to it.
  • 2.7K
  • 08 Oct 2022
Topic Review
Fuzzy VS Bivalent Logic
In this work a comparison is attempted between the Aristotle’s traditional bivalent logic, which dominated for centuries on the human way of thinking, and the relatively recent Zadeh’s fuzzy logic, which has already found many and important applications to almost all sectors of the human activity. It is concluded that, although the enormous progress of science and technology owes a lot to bivalent logic, fuzzy logic which completes and extends it, fits much better to our everyday life situations and to the scientific way of thinking.
  • 2.7K
  • 20 Feb 2021
Topic Review
Haemophilia
Haemophilia, or hemophilia (from grc αἷμα (Script error: No such module "Ancient Greek".) 'blood', and φιλία (Script error: No such module "Ancient Greek".) 'love of'), is a mostly inherited genetic disorder that impairs the body's ability to make blood clots, a process needed to stop bleeding. This results in people bleeding for a longer time after an injury, easy bruising, and an increased risk of bleeding inside joints or the brain. Those with a mild case of the disease may have symptoms only after an accident or during surgery. Bleeding into a joint can result in permanent damage while bleeding in the brain can result in long term headaches, seizures, or a decreased level of consciousness. There are two main types of haemophilia: haemophilia A, which occurs due to low amounts of clotting factor VIII, and haemophilia B, which occurs due to low levels of clotting factor IX. They are typically inherited from one's parents through an X chromosome carrying a nonfunctional gene. Rarely a new mutation may occur during early development or haemophilia may develop later in life due to antibodies forming against a clotting factor. Other types include haemophilia C, which occurs due to low levels of factor XI, and parahaemophilia, which occurs due to low levels of factor V. Acquired haemophilia is associated with cancers, autoimmune disorders, and pregnancy. Diagnosis is by testing the blood for its ability to clot and its levels of clotting factors. Prevention may occur by removing an egg, fertilizing it, and testing the embryo before transferring it to the uterus, which is connected with ethical problems. Human embryos in research can be regarded as the technical object/process. Missing blood clotting factors are replaced to treat haemophilia. This may be done on a regular basis or during bleeding episodes. Replacement may take place at home or in hospital. The clotting factors are made either from human blood or by recombinant methods. Up to 20% of people develop antibodies to the clotting factors which makes treatment more difficult. The medication desmopressin may be used in those with mild haemophilia A. Studies of gene therapy are in early human trials. Haemophilia A affects about 1 in 5,000–10,000, while haemophilia B affects about 1 in 40,000, males at birth. As haemophilia A and B are both X-linked recessive disorders, females are rarely severely affected. Some females with a nonfunctional gene on one of the X chromosomes may be mildly symptomatic. Haemophilia C occurs equally in both sexes and is mostly found in Ashkenazi Jews. In the 1800s haemophilia B was common within the royal families of Europe. The difference between haemophilia A and B was determined in 1952.
  • 2.7K
  • 27 Oct 2022
Topic Review
ΔT
In precise timekeeping, ΔT (Delta T, delta-T, deltaT, or DT) is a measure of the cumulative effect of the departure of the Earth's rotation period from the fixed-length day of atomic time. Formally it is the time difference obtained by subtracting Universal Time (UT, defined by the Earth's rotation) from Terrestrial Time (TT, independent of the Earth's rotation): ΔT = TT − UT. The value of ΔT for the start of 1902 was approximately zero; for 2002 it was about 64 seconds. So the Earth's rotations over that century took about 64 seconds longer than would be required for days of atomic time. As well as this long-term drift in the length of the day there are short-term fluctuations in the length of day (Δτ) which are dealt with separately.
  • 2.7K
  • 01 Nov 2022
Topic Review
Sustainable Tourism in the Rural Environment
The multiplicity of forms of tourism and leisure activities is due to many factors. These could be a tourist’s interests, curiosity about the world, cultural or recreational offerings, tourist resources, infrastructure, technical possibilities, or a destination understood as a specific area or type of landscape. One of the more popular forms, which combines some of these factors, is rural tourism.
  • 2.7K
  • 07 Feb 2024
Topic Review
Open-Cathode PEM Fuel Cells
Fuel cells were first introduced in aircraft as auxiliary power units; however, in recent years, there has been an increasing interest in using fuel cells, batteries, and, sometimes, supercapacitors for the electric propulsion of small aerial vehicles. Open cathode fuel cells are characterized by a light and simple balance of plant but the control of temperature is quite critical under variable conditions of load and altitude, typical of the aerospace application.
  • 2.7K
  • 22 Feb 2024
Topic Review
ABCDE Model of Sarcoidosis Care
The importance of comprehensive care in sarcoidosis is generally acknowledged [12,13]. Here, we describe the ABCDE model, that can be used to structure comprehensive sarcoidosis management in order to improve quality of life and outcomes for patients (Figure 1). This model includes the following components: the Assessment of symptoms and patient’s needs, Backing patients by providing support and education, treatment of Complaints and Comorbidities, Disease-modifying treatment, and the involvement of Extrapulmonary specialists. As disease activity, organ involvement, and patients’ preferences may vary during the disease course, regular reassessment is essential. The ABCDE model can provide guidance to clinicians during the first work-up and follow-up of patients with sarcoidosis.
  • 2.7K
  • 23 Oct 2020
Topic Review
Pyrazole Biomolecules as Cancer and Inflammation Therapeutics
The pyrazole moiety is a heterocyclic ring system (five membered) with 3 C and 2 N in adjacent sites. Pyrazole compounds have an extensive past of applications, being used as herbicides, agrochemicals, and as active pharmaceutical agents. Pyrazole derivatives exhibit anti-inflammatory properties and have been shown to target several cancer cell lines, such as COX (I/II).
  • 2.7K
  • 10 Feb 2023
Topic Review
Basalt Fibre Reinforced Composites
Basalt mineral fibre, made directly from basalt rock, has good mechanical behavior, superior thermal stability, better chemical durability, good moisture resistance and can easily be recycled when compared to E-glass fibres (borosilicate glass is called ‘E-glass’ or ‘electric al-grade glass’ because of its high electrical resistance) which are traditionally used in structural composites for industrial applications. Industrial adoption of basalt fibre reinforced composites (FRC) is still very low mainly due to inadequate data and lower production volumes leading to higher cost. These reasons constrain the composites industry from seriously considering basalt as a potential alternative to conventional (e.g., E-glass) fibre reinforced composites for different applications.
  • 2.7K
  • 17 Jan 2023
Topic Review
Calcium Transport Systems in Mitochondria
Calcium (Ca2+) is a divalent cation and a universal second messenger that regulates the most important functions and facets of all eukaryotic cells, including: gene expression, proliferation, regulation of bioenergetics, contraction of muscles, mediation of fertilization, and many other cellular functions. Regulation of free intracellular concentration of Ca2+ is an important mechanism for intracellular signaling, and it is a key component in the mediation of many cell functions and biochemical reactions, being crucial for signal transduction in cells. On top of all that, intra-mitochondrial Ca2+ regulates a cascade of physiological and pathophysiological processes in cells The normal level of intra-mitochondrial Са2+ is essential for the correct functioning of mitochondria; whereas Ca2+ overload is typical for a wide range of mitochondrial dysfunctions and pathophysiological processes. Homeostasis of Ca2+ in the mitochondria is determined by the delicate balance of mitochondrial Ca2+ transport systems in both the inner (IMM) and outer mitochondrial membrane (OMM). Ca2+ influx and efflux systems are composed of different components, including: channels, pumps, antiporters, or Ca2+ binding proteins that cooperate to maintain intra-mitochondrial Ca2+ homeostasis.
  • 2.7K
  • 18 Nov 2020
Topic Review
MXene: Recent Advances in Applications
This entry covers major breakthroughs of MXene and applications.
  • 2.7K
  • 28 Mar 2022
Topic Review
Caracal
The caracal (Caracal caracal) /ˈkærəkæl/ is a medium-sized wild cat native to Africa, the Middle East, Central Asia, and arid areas of Pakistan and northwestern India . It is characterised by a robust build, long legs, a short face, long tufted ears, and long canine teeth. Its coat is uniformly reddish tan or sandy, while the ventral parts are lighter with small reddish markings. It reaches 40–50 cm (16–20 in) at the shoulder and weighs 8–19 kg (18–42 lb). It was first scientifically described by German naturalist Johann Christian Daniel von Schreber in 1776. Three subspecies are recognised. Typically nocturnal, the caracal is highly secretive and difficult to observe. It is territorial, and lives mainly alone or in pairs. The caracal is a carnivore that typically preys upon small mammals, birds, and rodents. It can leap higher than 4 metres (12 ft) and catch birds in midair. It stalks its prey until it is within 5 m (16 ft) of it, after which it runs it down and kills its prey with a bite to the throat or to the back of the neck. Both sexes become sexually mature by the time they are one year old and breed throughout the year. Gestation lasts between two and three months, resulting in a litter of one to six kittens. Juveniles leave their mothers at the age of nine to ten months, though a few females stay back with their mothers. The average lifespan of captive caracals is nearly 16 years. Caracals were tamed and used for coursing in India, Persia and Egypt.
  • 2.7K
  • 24 Oct 2022
Topic Review
Characteristics and Hazards of Lead–Zinc Tailings
Lead–zinc tailings are the typical solid wastes in mines with high yield and low utilization rates in some countries. They are mainly stockpiled in tailings reservoirs, occupying massive land resources and threatening the health of the environment. 
  • 2.7K
  • 17 Jan 2023
Topic Review
The Subconjunctival Space of the Eye
The subconjunctival space is the hydrophilic, fluid-filled space between the conjunctiva and the sclera. Additionally, the subconjunctival space has access to all the blood vessels found in the conjunctiva, which can help to further distribute substances throughout the whole eye. The subconjunctival space is located superior to the cornea and optimally located to distribute drugs to several different parts of the eye through minimally invasive means while limiting the development of scar tissue.
  • 2.7K
  • 05 May 2022
Topic Review
Implication of P38 MAPK in drugs of abuse and stress
p38 mitogen-activated protein kinases (MAPKs) are key signaling molecules in cellular responses to external stresses and regulation of pro-inflammatory cytokines. Some studies have suggested that p38 MAPK in the region of the nucleus accumbens is involved in abnormal behavioral responses induced by drugs of abuse. In this entry, we recapitulate the role of the p38 MAPK in the rewarding effects of drugs of abuse. We also summarize the implication of p38 MAPK in stress, anxiety, and depression. We opine that p38 MAPK activation is more closely associated to stress-induced aversive responses rather than drug effects per se, in particular cocaine. p38 MAPK is only involved in cocaine reward, predominantly when promoted by stress. Downstream substrates of p38 that may contribute to the p38 MAPK associated-behavioral responses are proposed. Finally, we suggest p38 MAPK inhibitors as possible therapeutic interventions against stress-related disorders by potentially increasing resilience against stress and addiction relapse induced by adverse experiences.
  • 2.7K
  • 15 Jul 2020
Topic Review
Calcium Phosphate Nanocluster Complexes
Calcium phosphate nanocluster complexes comprise a core of amorphous calcium phosphate and a sequestering shell of intrinsically disordered phosphopeptides or phosphoproteins. Solutions containing the nanocluster complexes can be thermodynamically stable or metastable due to a tendency to form a precipitate enriched in calcium phosphate. Theoretical and biophysical studies with native and recombinant phosphopeptides have shown how the radius of the core and the stability of the solution depend on the concentration of the sequestering peptide, its affinity for the calcium phosphate and its concentration in relation to the concentration of the calcium phosphate. The thickness of the sequestering shell depends on the conformation of the peptide on the core surface. A sequestering peptide is a flexible sequence including one or more short linear motifs, each of which usually contains several phosphorylated and other acidic residues.  These are the main binding sites to the core so that a peptide with several binding motifs can forms loops and trains on the core surface. Calcium phosphate nanocluster complexes were first identified as substructures of casein micelles in milk and have been prepared as individual particles from peptides derived from caseins and osteopontin. Stable biofluids containing nanocluster complexes cannot cause soft tissues to become mineralized whereas stable or metastable biofluids containing nanocluster complexes can help to mineralize hard tissues.
  • 2.7K
  • 09 Nov 2020
Topic Review
Zeaxanthin and Photoprotection in Plants
Conversion of sunlight into photochemistry by plants depends on photoprotective processes that allow safe use of sunlight over a broad range of environmental conditions. This entry focuses on the universal use by plants of the photoprotector zeaxanthin that is part of a group of three interconvertible leaf carotenoids collectively known as the xanthophyll cycle. We survey the striking plasticity of this photoprotective process in nature that can be fine-tuned to produce a fit for different environments with various combinations of light, temperature, and other factors.
  • 2.7K
  • 26 Dec 2020
Topic Review
Olive Oil Production Wastes
The production of high-quality olive oils implies the generation of vast quantities of solid residues and/or wastewaters that may have a great impact on terrestrial and aquatic environments because of their high phytotoxicity. Depending on the techniques used for olive oil production, namely, on the type of horizontal centrifugation (two-phase or three-phase), the process most adopted to separate olive oil from olive paste obtained after malaxation, different by-products are obtained.
  • 2.7K
  • 28 Jun 2021
Topic Review
The Coming of Age of Biosimilars
The first biosimilar, Sandoz’s Omnitrope  (human growth hormone), was approved in 2006 by both the FDA and EMA; it was approved by the FDA under the 505(b)(2) generic product legislation and by the EU as a biosimilar. Later, Sandoz received the first licensing of Zarzio/Zarxio (filgrastim) in 2015; this was the first biosimilar product approved under the 351(k) BLA legislation in the US. Biosimilars have come of age from 2005 to the present, with 84 approvals in the EU and 35 in the US, representing almost 90% of the world market. While the acceptance of biosimilars in the US is catching up with that in the EU, the cost benefits remain elusive due to the high development barrier and complex distribution system involved, mainly in the US. In the EU, the cost of biosimilars has already dropped 70% or more, and interchangeability is a routine in some European jurisdictions, unlike in the US, where a separate regulatory approval is required.
  • 2.7K
  • 27 Apr 2022
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