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Topic Review
Multiphase Flows
Multiphase flows appear in many industrial and environmental applications (dredging, oil industry, mining industry, cement industry, among others), quite often as two-phase flows, either solid/liquid, liquid/liquid or gas/liquid flows. When we speak about multiphase flows we are referring both to flow in channels or pipes or in other process units. In our studies we have been more directed to multiphase flows in pipes. Being able to model and accurately predict the behaviour of such flows and to monitor, as well, the flows themselves, is of high importance to guarantee a stable flow and to optimize energy consumption, by designing adequately the conveying system, without the need to overdimensioning conveying equipment to avoid, for instance, pipe blockage.
  • 2.9K
  • 28 Jan 2021
Topic Review
Table olives microbiota
Table olives fermentation is the result of a complex set of dynamics involving diverse microbial populations such as lactic acid bacteria, yeasts and moulds. Their metabolic activities determine the characteristics such as flavour, texture and safety of the final product. This chapter offers an overview on the main microbiota characterizing table olives and their role during fermentation.
  • 2.9K
  • 01 Jul 2020
Topic Review
Cell Sheet Harvesting Techniques
Cell sheet engineering is an advanced scaffold-free tissue engineering technique applicable to repairing or regenerating defective tissues and organs. It has proven to be an important breakthrough technology in regenerative medicine. 
  • 2.9K
  • 24 Feb 2023
Topic Review
Advanced Bioengineered Skin Equivalents
The formation of severe scars still represents the result of the closure process of extended and deep skin wounds. To address this issue, different bioengineered skin substitutes have been developed but a general consensus regarding their effectiveness has not been achieved yet. It will be shown that bioengineered skin substitutes, although representing a valid alternative to autografting, induce skin cells in repairing the wound rather than guiding a regeneration process. Repaired skin differs from regenerated skin, showing high contracture, loss of sensitivity, impaired pigmentation and absence of cutaneous adnexa (i.e., hair follicles and sweat glands). This leads to significant mobility and aesthetic concerns, making the development of more effective bioengineered skin models a current need. The objective of this review is to determine the limitations of either commercially available or investigational bioengineered skin substitutes and how advanced skin tissue engineering strategies can be improved in order to completely restore skin functions after severe wounds.
  • 2.9K
  • 30 Jul 2020
Topic Review
FTIR for Vehicle Exhaust Emissions
In a Fourier Transform InfraRed (FTIR) spectrometer, some of the infrared (IR) radiation is absorbed by the sample, and some of it is passed through (transmitted). The resulting molecular absorption and transmission response can be used to identify the components of the sample and their concentration.
  • 2.9K
  • 20 Aug 2021
Topic Review
Chelicerata
The subphylum Chelicerata (from New Latin, from fr chélicère, from grc χηλή (Script error: No such module "Ancient Greek".) 'claw, chela', and κέρας (Script error: No such module "Ancient Greek".) 'horn') constitutes one of the major subdivisions of the phylum Arthropoda. It contains the sea spiders, horseshoe crabs, and arachnids (including harvestmen, scorpions, spiders, solifuges, ticks, and mites, among many others), as well as a number of extinct lineages, such as the eurypterids (sea scorpions) and chasmataspidids. The Chelicerata originated as marine animals in the Middle Cambrian period; the first confirmed chelicerate fossils, belonging to Sanctacaris, date from 508 million years ago. The surviving marine species include the four species of xiphosurans (horseshoe crabs), and possibly the 1,300 species of pycnogonids (sea spiders), if the latter are indeed chelicerates. On the other hand, there are over 77,000 well-identified species of air-breathing chelicerates, and there may be about 500,000 unidentified species. Like all arthropods, chelicerates have segmented bodies with jointed limbs, all covered in a cuticle made of chitin and proteins. The chelicerate body plan consists of two tagmata, the prosoma and the opisthosoma, except that mites have lost a visible division between these sections. The chelicerae, which give the group its name, are the only appendages that appear before the mouth. In most sub-groups, they are modest pincers used to feed. However, spiders' chelicerae form fangs that most species use to inject venom into prey. The group has the open circulatory system typical of arthropods, in which a tube-like heart pumps blood through the hemocoel, which is the major body cavity. Marine chelicerates have gills, while the air-breathing forms generally have both book lungs and tracheae. In general, the ganglia of living chelicerates' central nervous systems fuse into large masses in the cephalothorax, but there are wide variations and this fusion is very limited in the Mesothelae, which are regarded as the oldest and most basal group of spiders. Most chelicerates rely on modified bristles for touch and for information about vibrations, air currents, and chemical changes in their environment. The most active hunting spiders also have very acute eyesight. Chelicerates were originally predators, but the group has diversified to use all the major feeding strategies: predation, parasitism, herbivory, scavenging and eating decaying organic matter. Although harvestmen can digest solid food, the guts of most modern chelicerates are too narrow for this, and they generally liquidize their food by grinding it with their chelicerae and pedipalps and flooding it with digestive enzymes. To conserve water, air-breathing chelicerates excrete waste as solids that are removed from their blood by Malpighian tubules, structures that also evolved independently in insects. While the marine horseshoe crabs rely on external fertilization, air-breathing chelicerates use internal but usually indirect fertilization. Many species use elaborate courtship rituals to attract mates. Most lay eggs that hatch as what look like miniature adults, but all scorpions and a few species of mites keep the eggs inside their bodies until the young emerge. In most chelicerate species the young have to fend for themselves, but in scorpions and some species of spider the females protect and feed their young. The evolutionary origins of chelicerates from the early arthropods have been debated for decades. Although there is considerable agreement about the relationships between most chelicerate sub-groups, the inclusion of the Pycnogonida in this taxon has recently been questioned (see below), and the exact position of scorpions is still controversial, though they were long considered the most basal of the arachnids. Venom has evolved three times in the chelicerates; spiders, scorpions and pseudoscorpions, or four times if the hematophagous secretions produced by ticks are included. In addition there have been undocumented descriptions of venom glands in Solifugae. Chemical defense has been found in whip scorpions, shorttailed whipscorpions, harvestmen, beetle mites and sea spiders. Although the venom of a few spider and scorpion species can be very dangerous to humans, medical researchers are investigating the use of these venoms for the treatment of disorders ranging from cancer to erectile dysfunction. The medical industry also uses the blood of horseshoe crabs as a test for the presence of contaminant bacteria. Mites can cause allergies in humans, transmit several diseases to humans and their livestock, and are serious agricultural pests.
  • 2.9K
  • 18 Oct 2022
Topic Review
Plasticity
In physics and materials science, plasticity, also known as plastic deformation, is the ability of a solid material to undergo permanent deformation, a non-reversible change of shape in response to applied forces. For example, a solid piece of metal being bent or pounded into a new shape displays plasticity as permanent changes occur within the material itself. In engineering, the transition from elastic behavior to plastic behavior is known as yielding. Plastic deformation is observed in most materials, particularly metals, soils, rocks, concrete, and foams. However, the physical mechanisms that cause plastic deformation can vary widely. At a crystalline scale, plasticity in metals is usually a consequence of dislocations. Such defects are relatively rare in most crystalline materials, but are numerous in some and part of their crystal structure; in such cases, plastic crystallinity can result. In brittle materials such as rock, concrete and bone, plasticity is caused predominantly by slip at microcracks. In cellular materials such as liquid foams or biological tissues, plasticity is mainly a consequence of bubble or cell rearrangements, notably T1 processes. For many ductile metals, tensile loading applied to a sample will cause it to behave in an elastic manner. Each increment of load is accompanied by a proportional increment in extension. When the load is removed, the piece returns to its original size. However, once the load exceeds a threshold – the yield strength – the extension increases more rapidly than in the elastic region; now when the load is removed, some degree of extension will remain. Elastic deformation, however, is an approximation and its quality depends on the time frame considered and loading speed. If, as indicated in the graph opposite, the deformation includes elastic deformation, it is also often referred to as "elasto-plastic deformation" or "elastic-plastic deformation". Perfect plasticity is a property of materials to undergo irreversible deformation without any increase in stresses or loads. Plastic materials that have been hardened by prior deformation, such as cold forming, may need increasingly higher stresses to deform further. Generally, plastic deformation is also dependent on the deformation speed, i.e. higher stresses usually have to be applied to increase the rate of deformation. Such materials are said to deform visco-plastically.
  • 2.9K
  • 10 Nov 2022
Topic Review
Compressed Air Energy Storage
The recent increase in the use of carbonless energy systems have resulted in the need for reliable energy storage due to the intermittent nature of renewables. Among the existing energy storage technologies, compressed-air energy storage (CAES) has significant potential to meet techno-economic requirements in different storage domains due to its long lifespan, reasonable cost, and near-zero self-decay. 
  • 2.9K
  • 25 Sep 2023
Topic Review
Fiber-Reinforced Geopolymer Composite
Fiber-reinforced geopolymer composite (FRGC) is emerging as one of the alternative materials for cement in the construction industry. FRGC is considered an eco-friendly material due to its role in the global reduction in emission of CO2 to the environment. Simultaneously, the composite provides good mechanical strength of flexural modulus, loss modulus, post-impact strength, and durability for a definite period at room and elevated temperatures. A positive aspect of the geopolymer matrix used for this composite is that could provide a finite period of durability at elevated temperatures without releasing toxic gases to the surroundings. Fibers enhanced the brittle behavior of the geopolymer matrix into ductile one with improved mechanical strength and residual impact strength.
  • 2.9K
  • 09 Jul 2021
Topic Review
Q'uq'umatz
Q'uq'umatz (Mayan: [qʔuː qʔuːˈmats]) (alternatively Qucumatz, Gukumatz, Gucumatz, Gugumatz, Kucumatz etc.) was a deity of the Postclassic K'iche' Maya. Q'uq'umatz was the Feathered Serpent divinity of the Popol Vuh who created humanity together with the god Tepeu. Q'uq'umatz is considered to be the rough equivalent of the Aztec god Quetzalcoatl, and also of Kukulkan of the Yucatec Maya tradition. It is likely that the feathered serpent deity was borrowed from one of these two peoples and blended with other deities to provide the god Q'uq'umatz that the K'iche' worshipped. Q'uq'umatz may have had his origin in the Valley of Mexico; some scholars have equated the deity with the Aztec deity Ehecatl-Quetzalcoatl, who was also a creator god. Q'uq'umatz may originally have been the same god as Tohil, the K'iche' sun god who also had attributes of the feathered serpent, but they later diverged and each deity came to have a separate priesthood. Q'uq'umatz was one of the gods who created the world in the Popul Vuh, the K'iche' creation epic. Q'uq'umatz, god of wind and rain, was closely associated with Tepeu, god of lightning and fire. Both of these deities were considered to be the mythical ancestors of the K'iche' nobility by direct male line. Q'uq'umatz carried the sun across the sky and down into the underworld and acted as a mediator between the various powers in the Maya cosmos. The deity was particularly associated with water, clouds, the wind and the sky. Kotuja', the K'iche' king who founded the city of Q'umarkaj, bore the name of the deity as a title and was likely to have been a former priest of the god. The priests of Q'uq'umatz at Q'umarkaj, the K'iche' capital, were drawn from the dominant Kaweq dynasty and acted as stewards in the city.
  • 2.9K
  • 21 Nov 2022
Topic Review
NF-κB
The family of NF-κB is composed of five members of proteins linking to DNA, (RelA, RelB, RelC, NFκ-B1, and NFκ-B2) that trigger a set of inflammatory downstream effectors after nuclear translocation, involved in a broad range of biological processes. Either a canonical or a non-canonical pathway can be responsible for their activation; the canonical pathway mediates inflammatory responses and leads to a rapid but transient NF-κB activation, while the non-canonical signalling is a slow, long-lasting pathway.
  • 2.9K
  • 27 Oct 2020
Topic Review
Carbon Nanodots: Antimicrobial Photosensitizers
Carbon nanodots are fluorescent, quasi-spherical nanoparticles that have been investigated and modified for numerous applications. In recent years, the utility of these structures for antimicrobial photodynamic therapy (APDT) has been of increasing interest. For this technology, light is used to trigger the generation of reactive oxygen species which subsequently inactivate or kill pathogenic microorganisms. Carbon nanodots are of interest for this application due to their simple, "green" synthesis methods and their tunable organic structures and luminescent properties. Herein we share some recent developments in the field of antimicrobial carbon nanodots, highlighting their increasing relevance and potential in this area.
  • 2.9K
  • 25 Sep 2020
Topic Review
Sustainable Development Goals
Sürdürülebilir kalkınma hedefleri (SDG'ler), 2015'te kabul edilen 17 hedefi içeren, BM'nin herkes için daha iyi ve daha sürdürülebilir bir gelecek elde etme planının küresel bir kalkınma programıdır. Yoksulluk, eşitsizlik, iklim değişikliği dahil olmak üzere küresel nüfusun karşılaştığı zorlukları ele alırlar. , çevresel bozulma, barış ve adalet. Programlar genellikle sürdürülebilir ekonomik büyümeyi ve sürdürülebilir kalkınma için 2030 gündemini uygulamak için sürdürülebilirliğin güçlendirilmesi modlarını vurgular. Bu SDG'lerden SDGS 7, 8, 9, 11, 12 ve 17, doğrudan ve/veya dolaylı olarak sürdürülebilirlik ve döngüsellik fenomeniyle bağlantılıdır. Birleşmiş Milletler'in (BM) SKH'lerine imza atan ülkelerdeki hükümetler, ulusal politika ve programlar da dahil olmak üzere farklı eylemlerde bulunarak hedefe ulaşılmasında çok önemli bir rol oynamaktadır,
  • 2.9K
  • 03 Nov 2022
Topic Review
New Chronology (Rohl)
New Chronology is an alternative chronology of the ancient Near East developed by English Egyptologist David Rohl and other researchers beginning with A Test of Time: The Bible - from Myth to History in 1995. It contradicts mainstream Egyptology by proposing a major revision of the established Egyptian chronology, in particular by re-dating Egyptian kings of the Nineteenth through Twenty-fifth Dynasties, bringing forward conventional dating by up to 350 years. Rohl asserts that the New Chronology allows him to identify some of the characters in the Hebrew Bible with people whose names appear in archaeological finds. The New Chronology, one of several proposed radical revisions of the conventional chronology, has not been accepted in academic Egyptology, where the conventional chronology or small variations of it remain standard. Amélie Kuhrt, head of Ancient Near Eastern History at University College London, in one of the standard reference works of the discipline, notes: "Many scholars feel sympathetic to the critique of weaknesses in the existing chronological framework [...], but most archaeologists and ancient historians are not at present convinced that the radical redatings proposed stand up to close examination." Rohl's most vocal critic has been Kenneth Kitchen, one of the leading experts on biblical history and the author of the standard work on the conventional chronology of the Third Intermediate Period of Egypt, the period most directly affected by the New Chronology's redating of the Nineteenth to Twenty-fifth Dynasties.
  • 2.9K
  • 20 Oct 2022
Topic Review
Encoding (Memory)
Memory has the ability to encode, store and recall information. Memories give an organism the capability to learn and adapt from previous experiences as well as build relationships. Encoding allows a perceived item of use or interest to be converted into a construct that can be stored within the brain and recalled later from long-term memory. Working memory stores information for immediate use or manipulation which is aided through hooking onto previously archived items already present in the long-term memory of an individual.
  • 2.9K
  • 17 Nov 2022
Topic Review
Seed Waste from Custard Apple
Annona squamosa L. (custard apple or sugar apple), belonging to the Annonaceae family, is a small tree or shrub that grows natively in subtropical and tropical regions. Seeds of the custard apple have been employed in folk medicines because of the presence of bioactive chemicals/compounds such as alkaloids, flavonoids and phenolic compounds and acetogenins and cyclopeptides that are responsible for various biological activities. The seeds also show the presence of tannins, vitamin C, vitamin E and a higher content of amino acids. From investigations, it has been shown that the seeds of A. squamosa have considerable potential to be used as an antibacterial, hepatoprotective, antioxidant and antitumor/anticancer agent. Cyclosquamosin B, extracted from the custard apple seed, possesses vasorelaxant properties. Tocopherols and fatty acids, notably oleic acid and linoleic acid, are also found in the seed oil. A. squamosa seeds contain a high amount of annonaceous acetogenins compounds, which are potent mitochondrial complex I inhibitors and have high cytotoxicity. A survey primarily based on the nutritional, phytochemical and biological properties showed that A. squamosa seeds can be used for the discovery of novel products, including pharmaceutical drugs.
  • 2.9K
  • 01 Nov 2022
Topic Review
Mechanochemical Synthesis of Nanoparticles
Various solvent-based approaches have been already used to synthesize porous materials. Mechanochemical synthesis is one of the effective eco-friendly alternatives to the conventional synthesis. It adopts the efficient mixing of reactants using ball milling without or with a very small volume of solvents, gives smaller size nanoparticles (NPs) and larger surface area, and facilitates their functionalization, which is highly beneficial for antimicrobial applications.
  • 2.9K
  • 15 Mar 2023
Topic Review Peer Reviewed
Merging Smart and Healthy Cities to Support Community Wellbeing and Social Connection
Urban planning has long pursued the improvement of health and wellbeing through the rapidly evolving scholarship and practice of health-supportive environments, underpinned by the seminal World Health Organization’s Healthy Cities Framework. Although a much more recent development, technology has been informing urban planning, as well as advancing healthcare and personal wellbeing monitoring and assessment. Known as the Smart City movement, it has much to offer regarding life in towns and cities, as well as how they are managed, maintained, and developed. There is also a growing appreciation of the potential for smart city technology to enhance human and environmental health in the context of urban planning and public place making. This has been reinforced by the COVID-19 pandemic with its reawakening of community interest in health and wellbeing, including mental illness, a greater awareness of the importance of local environments, and an explosion of technological knowhow in the embrace of remote working, online shopping, and education. Using the example of the authors’ “Smart Social Spaces” project, this entry discusses the potential benefits of an evolving integrative concept called “Smart Healthy Social Spaces”. The aim is to support community wellbeing as part of everyday living, especially associated with social connection, in densely populated and culturally diverse urban environments, where locally situated public spaces are increasingly important for all citizens.
  • 2.9K
  • 04 Sep 2023
Topic Review
Hot dip galvanizing
Hot-dip galvanizing is one of the most effective methods of protecting steel against corrosion. It allows one to obtain good quality coatings, ensuring long-term protection with relatively low operating costs of the coatings.
  • 2.9K
  • 29 Oct 2020
Topic Review
Trypanosomatid Pathogens
Unicellular eukaryotes of the Trypanosomatidae family include human and animal pathogens that belong to the Trypanosoma and Leishmania genera. Diagnosis of the diseases they caused requires the sampling of body fluids (blood, lymph, peritoneal fluid, cerebrospinal fluid, etc.) or organ biopsies (bone marrow, spleen, etc.), which are mostly obtained through invasive methods. Body fluids or appendages can be alternatives to these invasive biopsies but their appropriateness remains poorly studied. To further address this question, we perform a systematic review on clues evidencing the presence of parasites, genetic material, antibodies, and antigens in body secretions, appendages, or the organs or proximal tissues that produce these materials.
  • 2.9K
  • 29 Oct 2020
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