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Topic Review

Thiazoles and Bisthiazoles

Thiazole, a five-membered heteroaromatic ring, is an important scaffold of a large number of synthetic compounds. Its diverse pharmacological activity is reflected in many clinically approved thiazole-containing molecules, with an extensive range of biological activities, such as antibacterial, antifungal, antiviral, antiparasitic, antitumor, antiparkinsonian, and anti-inflammatory effects.

6.9K
29 Mar 2021

Topic Review

Drying Methods of Probiotic Formulations

Preparations containing probiotic strains of bacteria have a beneficial effect on human and animal health. Concentrated probiotic bacteria used in animal nutrition and consumed by humans most commonly occur in the form of dried biomass. The benefits of probiotics translate into an increased interest in techniques for the preservation of microorganisms.

6.9K
18 Aug 2022

Topic Review

Tetrodotoxin (TTX) is a crystalline, weakly basic, colorless organic substance and is one of the most potent marine toxins known. Although TTX was first isolated from pufferfish, it has been found in numerous other marine organisms and a few terrestrial species.

6.9K
18 Jan 2022

Topic Review

The "Vimana" is one such concept in ancient Indian texts that has been in the spotlight of most scholars, historians, and enthusiasts of ancient technology. Indeed, Vimanas, as they are described in Hindu epics or Vedic literature, flying machines or celestial chariots have amazed many a knowledgeable intellect, and some even go to the extent of citing them as evidence for advanced knowledge in aeronautical science in ancient India.

6.9K
31 Oct 2024

Topic Review

Digital twins in pharmaceutical manufacturing

The development and application of emerging technologies of Industry 4.0 enable the realization of digital twins (DT), which facilitates the transformation of the manufacturing sector to a more agile and intelligent one. DTs are virtual constructs of physical systems that mirror the behavior and dynamics of such physical systems. A fully developed DT consists of physical components, virtual components, and information communications between the two. Integrated DTs are being applied in various processes and product industries. Although the pharmaceutical industry has evolved recently to adopt Quality-by-Design (QbD) initiatives and is undergoing a paradigm shift of digitalization to embrace Industry 4.0, there has not been a full DT application in pharmaceutical manufacturing. Therefore, there is a critical need to examine the progress of the pharmaceutical industry towards implementing DT solutions. The aim of this entry is to give an overview of the current status of DT development and its application in pharmaceutical and biopharmaceutical manufacturing. State-of-the-art Process Analytical Technology (PAT) developments, process modeling approaches, and data integration studies are reviewed. Challenges and opportunities for future research in this field are also discussed.

6.9K
09 Mar 2022

Topic Review

Aesthetics, or esthetics, is a branch of philosophy that deals with the nature of beauty and taste, as well as the philosophy of art (its own area of philosophy that comes out of aesthetics). It examines aesthetic values, often expressed through judgments of taste. Aesthetics covers both natural and artificial sources of experiences and how we form a judgment about those sources. It considers what happens in our minds when we engage with objects or environments such as viewing visual art, listening to music, reading poetry, experiencing a play, watching a fashion show, movie, sports or even exploring various aspects of nature. The philosophy of art specifically studies how artists imagine, create, and perform works of art, as well as how people use, enjoy, and criticize art. Aesthetics considers why people like some works of art and not others, as well as how art can affect moods or even our beliefs. Both aesthetics and the philosophy of art ask questions like "What is art?," "What is a work of art?," and "What makes good art?" Scholars in the field have defined aesthetics as "critical reflection on art, culture and nature". In modern English, the term "aesthetic" can also refer to a set of principles underlying the works of a particular art movement or theory (one speaks, for example, of a Renaissance aesthetic).

6.9K
04 Nov 2022

Topic Review

Wooden Boats of World War 2

Splinter fleet or Splinter navy was a nickname given to the wooden boats used in World War II. The boats served in many different roles during the war. These boats were built in small boatyards on the West coast and East coast, Great Lakes and the Gulf of Mexico. They could be built quickly, in just 60 to 120 days. Most of the boats were built by boatyards that already had the tools and knowledge from building yachts, sailboats and motor boats. Many were built by craftsmen in family-owned small businesses. Under the Emergency Shipbuilding Program and War Shipping Administration contracts went out to over fifty boatyards across the country. The boats were built for the US Navy, the, United States Army Air Forces , United States Coast Guard, and US Army. Some of the wooden boats went to Allied nations on the Lend-Lease program. In addition to new boat construction, some wooden boats built between 1910 and 1941 were acquired for the war effort, some used as-is and others converted for war use. Wooden boats have lighter weight and are easier to repair than steel hull boats. These wooden boats ranged from 19 to 200 feet in length. Some worked near shore and others working in the open ocean, called the Blue-water navy. The Splinter fleet is in contrast to the more common steel hull war ships and Merchant Marine ships. After the war, many of these boats were deemed not needed. Many were abandoned or destroyed, a few served in the Korean war and a few in the Vietnam War, some sold to private and some donated. During World War I there was a debate as to if wooden boats and ships should be used in war time. William Denman, President of the Emergency Fleet Corporation supported the building of wooden ships for the war and General Goethals disapproved. In the end, both men turned in their resignation over the heated debate. During World War II the situation was different. There was a shortage of steel and steel shipyards, so there was no debate about the need for a vast wooden fleet of boats and ships.

6.9K
14 Oct 2022

Topic Review

Philosophy of Max Stirner

The philosophy of Max Stirner is credited as a major influence in the development of individualism, nihilism, existentialism, post-modernism and anarchism (especially of egoist anarchism, individualist anarchism, postanarchism and post-left anarchy). Max Stirner's main philosophical work was The Ego and Its Own, also known as The Ego and His Own (Der Einzige und sein Eigentum in German, or more accurately The Individual and its Property). Stirner's philosophy has been cited as an influence on both his contemporaries, most notably Karl Marx (who was strongly opposed to Stirner's views) as well as subsequent thinkers such as Friedrich Nietzsche, Enrico Arrigoni, Steven T. Byington, Benjamin Tucker, Émile Armand and Albert Camus

6.8K
21 Oct 2022

Topic Review

Production of Chitosan Nanoparticles

Chitosan Nanoparticles are made from chitosan or its derivatives. The N-deacetylated derivative of chitin is an appealing biopolymer for producing nanoparticles because chitosan has a unique polymeric cationic nature, non-toxicity, high biocompatibility, mucoadhesive properties, absorption-enhancing qualities, and biodegradability.

6.8K
08 Oct 2022

Topic Review

Colorimetric Sensors

Colorimetric analysis has become of great importance in recent years to improve the operationalization of plasmonic-based biosensors. The unique properties of nanomaterials have enabled the development of a variety of plasmonics applications on the basis of the colorimetric sensing provided by metal nanoparticles. In particular, the extinction of localized surface plasmon resonance (LSPR) in the visible range has permitted the exploitation of LSPR colorimetric-based biosensors as powerful tools for clinical diagnostics and drug monitoring. This review summarizes recent progress in the biochemical monitoring of clinical biomarkers by ultrasensitive plasmonic colorimetric strategies according to the distance- or the morphology/size-dependent sensing modes. Colorimetric analysis has become of great importance in recent years to improve the operationalization of plasmonic-based biosensors. The unique properties of nanomaterials have enabled the development of a variety of plasmonics applications on the basis of the colorimetric sensing provided by metal nanoparticles. In particular, the extinction of localized surface plasmon resonance (LSPR) in the visible range has permitted the exploitation of LSPR colorimetric-based biosensors as powerful tools for clinical diagnostics and drug monitoring. This review summarizes recent progress in the biochemical monitoring of clinical biomarkers by ultrasensitive plasmonic colorimetric strategies according to the distance- or the morphology/size-dependent sensing modes.

6.8K
03 Nov 2020

Topic Review

In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridisation, which include genetic and morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo. Some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering times, pollen vectors, inhibition of pollen tube growth, somatoplastic sterility, cytoplasmic-genic male sterility and the structure of the chromosomes. A few animal species and many plant species, however, are the result of hybrid speciation, including important crop plants such as wheat, where the number of chromosomes has been doubled. Human impact on the environment has resulted in an increase in the interbreeding between regional species, and the proliferation of introduced species worldwide has also resulted in an increase in hybridisation. This genetic mixing may threaten many species with extinction, while genetic erosion from monoculture in crop plants may be damaging the gene pools of many species for future breeding. A form of often intentional human-mediated hybridisation is the crossing of wild and domesticated species. This is common in both traditional horticulture and modern agriculture; many commercially useful fruits, flowers, garden herbs, and trees have been produced by hybridisation. One such flower, Oenothera lamarckiana, was central to early genetics research into mutationism and polyploidy. It is also more occasionally done in the livestock and pet trades; some well-known wild × domestic hybrids are beefalo and wolfdogs. Human selective breeding of domesticated animals and plants has resulted in the development of distinct breeds (usually called cultivars in reference to plants); crossbreeds between them (without any wild stock) are sometimes also imprecisely referred to as "hybrids". Hybrid humans existed in prehistory. For example, Neanderthals and anatomically modern humans are thought to have interbred as recently as 40,000 years ago. Mythological hybrids appear in human culture in forms as diverse as the Minotaur, blends of animals, humans and mythical beasts such as centaurs and sphinxes, and the Nephilim of the Biblical apocrypha described as the wicked sons of fallen angels and attractive women.

6.8K
24 Nov 2022

Topic Review

Polymers for Pharmaceutical Coating

Coating the solid dosage form, such as tablets, is considered common, but it is a critical process that provides different characteristics to tablets. It increases the value of solid dosage form, administered orally, and thus meets diverse clinical requirements. As tablet coating is a process driven by technology, it relies on advancements in coating techniques, equipment used for the coating process, evaluation of coated tablets, and coated material used. Although different techniques were employed for coating purposes, which may be based on the use of solvents or solvent-free, each of the methods used has its advantages and disadvantages, and the techniques need continued modification too. During the process of film coating, several inter-and intra-batch uniformity of coated material on the tablets is considered a critical point that ensures the worth of the final product, particularly for those drugs that contain an active medicament in the coating layer. Meanwhile, computational modeling and experimental evaluation were actively used to predict the impact of the operational parameters on the final product quality and optimize the variables in tablet coating. The efforts produced by computational modeling or experimental evaluation not only save cost in optimizing the coating process but also saves time.

6.8K
13 Sep 2022

Topic Review

Microalgae/Cyanobacteria in Biodegradation of Plastics

Cyanobacteria (e.g., Synechocystis sp. PCC 6803, and Synechococcus elongatus PCC 7942), which are photosynthetic prokaryotes and were previously identified as blue-green algae, are currently under close attention for their abilities to capture solar energy and the greenhouse gas carbon dioxide for the production of high-value products. In the last few decades, these microorganisms have been exploited for different purposes (e.g., biofuels, antioxidants, fertilizers, and ‘superfood’ production). Microalgae (e.g., Chlamydomonas reinhardtii, and Phaeodactylum tricornutum) are also suitable for environmental and biotechnological applications based on the exploitation of solar light. In recent years, several studies have been targeting the utilization of microorganisms for plastic bioremediation. Among the different phyla, the employment of wild-type or engineered cyanobacteria may represent an interesting, environmentally friendly, and sustainable option (e.g., mismanaged plastics as source of carbons for their cultivation: the connection between their simultaneous utilization for biofuels or chemicals production and microplastics consumption on the surface of basins).

6.8K
05 Jan 2021

Topic Review

Sensor-Based Solid Waste Handling Systems

As a consequence of swiftly growing populations in the urban areas, larger quantities of solid waste also form rapidly. Since urban local bodies are found to be unable to manage this perilous situation effectively, there is a high probability of risks relative to the environment and public health. A sudden change is indispensable in the existing systems that are developed for the collection, transportation, and disposal of solid waste, which are entangled in turmoil. However, Smart sensors and wireless technology enable cyber-physical systems to automate solid waste management, which will revolutionize the industry.

6.8K
01 Apr 2022

Topic Review

The gastropods (/ˈɡæstrəpɒdz/), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (/ɡæsˈtrɒpədə/). This class comprises snails and slugs from saltwater, from freshwater, and from the land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, and land snails and slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Late Cambrian. (As of 2017), 721 families of gastropods are known, of which 245 are extinct and appear only in the fossil record, while 476 are currently extant with or without a fossil record. Gastropoda (previously known as univalves and sometimes spelled "Gasteropoda") are a major part of the phylum Mollusca, and are the most highly diversified class in the phylum, with 65,000 to 80,000 living snail and slug species. The anatomy, behavior, feeding, and reproductive adaptations of gastropods vary significantly from one clade or group to another, so stating many generalities for all gastropods is difficult. The class Gastropoda has an extraordinary diversification of habitats. Representatives live in gardens, woodland, deserts, and on mountains; in small ditches, great rivers, and lakes; in estuaries, mudflats, the rocky intertidal, the sandy subtidal, the abyssal depths of the oceans, including the hydrothermal vents, and numerous other ecological niches, including parasitic ones. Although the name "snail" can be, and often is, applied to all the members of this class, commonly this word means only those species with an external shell big enough that the soft parts can withdraw completely into it. Those gastropods without a shell, and those with only a very reduced or internal shell, are usually known as slugs; those with a shell into which they can partly but not completely withdraw are termed semislugs. The marine shelled species of gastropods include species such as abalone, conches, periwinkles, whelks, and numerous other sea snails that produce seashells that are coiled in the adult stage—though in some, the coiling may not be very visible, for example in cowries. In a number of families of species, such as all the various limpets, the shell is coiled only in the larval stage, and is a simple conical structure after that.

6.8K
08 Nov 2022

Topic Review

Propranolol in Post-Traumatic Stress Disorder

Propranolol, a non-cardioselective β1,2 blocker, is most commonly recognised for its application in the therapy of various cardiovascular conditions, such as hypertension, coronary artery disease, and tachyarrhythmias. However, due to its ability to cross the blood–brain barrier and affinity towards multiple macromolecules, not only adrenoreceptors, it has also found application in other fields. For example, it is one of the very few medications successfully applied in the treatment of stage fright.

6.8K
07 Sep 2022

Topic Review

Hypertensive Nephropathy

Hypertension is one of the most common risk factors for developing chronic cardiovascular diseases, including hypertensive nephropathy. Within the glomerulus, hypertension causes damage and activation of mesangial cells (MCs), eliciting the production of large amounts of vasoactive and proinflammatory agents. Accordingly, the activation of AT1 receptors by the vasoactive molecule angiotensin II (AngII) contributes to the pathogenesis of renal damage, which is mediated mostly by the dysfunction of intracellular Ca2+ ([Ca2+]i) signaling. Similarly, inflammation entails complex processes, where [Ca2+]i also play crucial roles. Deregulation of this second messenger increases cell damage and promotes fibrosis, reduces renal blood flow, and impairs the glomerular filtration barrier. In vertebrates, [Ca2+]i signaling depends, in part, on the activity of two families of large-pore channels: hemichannels and pannexons. Interestingly, the opening of these channels depends on [Ca2+]i signaling.

6.8K
23 Dec 2022

Topic Review

Transmission Electron Microscopy

Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a sensor such as a scintillator attached to a charge-coupled device. Transmission electron microscopes are capable of imaging at a significantly higher resolution than light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands of times smaller than a resolvable object seen in a light microscope. Transmission electron microscopy is a major analytical method in the physical, chemical and biological sciences. TEMs find application in cancer research, virology, and materials science as well as pollution, nanotechnology and semiconductor research, but also in other fields such as paleontology and palynology. TEM instruments have multiple operating modes including conventional imaging, scanning TEM imaging (STEM), diffraction, spectroscopy, and combinations of these. Even within conventional imaging, there are many fundamentally different ways that contrast is produced, called "image contrast mechanisms". Contrast can arise from position-to-position differences in the thickness or density ("mass-thickness contrast"), atomic number ("Z contrast", referring to the common abbreviation Z for atomic number), crystal structure or orientation ("crystallographic contrast" or "diffraction contrast"), the slight quantum-mechanical phase shifts that individual atoms produce in electrons that pass through them ("phase contrast"), the energy lost by electrons on passing through the sample ("spectrum imaging") and more. Each mechanism tells the user a different kind of information, depending not only on the contrast mechanism but on how the microscope is used—the settings of lenses, apertures, and detectors. What this means is that a TEM is capable of returning an extraordinary variety of nanometer- and atomic-resolution information, in ideal cases revealing not only where all the atoms are but what kinds of atoms they are and how they are bonded to each other. For this reason TEM is regarded as an essential tool for nanoscience in both biological and materials fields. The first TEM was demonstrated by Max Knoll and Ernst Ruska in 1931, with this group developing the first TEM with resolution greater than that of light in 1933 and the first commercial TEM in 1939. In 1986, Ruska was awarded the Nobel Prize in physics for the development of transmission electron microscopy.

6.8K
05 Dec 2022

Topic Review

Ecliptic Coordinate System

The ecliptic coordinate system is a celestial coordinate system commonly used for representing the apparent positions, orbits, and pole orientations of Solar System objects. Because most planets (except Mercury) and many small Solar System bodies have orbits with only slight inclinations to the ecliptic, using it as the fundamental plane is convenient. The system's origin can be the center of either the Sun or Earth, its primary direction is towards the vernal (March) equinox, and it has a right-hand convention. It may be implemented in spherical or rectangular coordinates.

6.8K
19 Oct 2022

Topic Review

In physics, deformation is the continuum mechanics transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body. A deformation can occur because of external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. Strain is related to deformation in terms of relative displacement of particles in the body that excludes rigid-body motions. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor or its dual is considered. In a continuous body, a deformation field results from a stress field due to applied forces or because of some changes in the temperature field of the body. The relation between stress and strain is expressed by constitutive equations, e.g., Hooke's law for linear elastic materials. Deformations which cease to exist after the stress field is removed are termed as elastic deformation. In this case, the continuum completely recovers its original configuration. On the other hand, irreversible deformations remain. They exist even after stresses have been removed. One type of irreversible deformation is plastic deformation, which occurs in material bodies after stresses have attained a certain threshold value known as the elastic limit or yield stress, and are the result of slip, or dislocation mechanisms at the atomic level. Another type of irreversible deformation is viscous deformation, which is the irreversible part of viscoelastic deformation. In the case of elastic deformations, the response function linking strain to the deforming stress is the compliance tensor of the material.

6.8K
21 Oct 2022

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