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Topic Review
Strain
In chemistry, a molecule experiences strain when its chemical structure undergoes some stress which raises its internal energy in comparison to a strain-free reference compound. The internal energy of a molecule consists of all the energy stored within it. A strained molecule has an additional amount of internal energy which an unstrained molecule does not. This extra internal energy, or strain energy, can be likened to a compressed spring. Much like a compressed spring must be held in place to prevent release of its potential energy, a molecule can be held in an energetically unfavorable conformation by the bonds within that molecule. Without the bonds holding the conformation in place, the strain energy would be released.
  • 5.0K
  • 04 Nov 2022
Topic Review
Lignocellulosic biomass (LC biomass)
      Bioenergy represents energy from biomass and plays an important role in promoting renewable alternatives. LC biomass is one of the most generous renewable bioresources in nature containing lignin, cellulose, and hemicelluloses. Lignocellulosic materials are the best sources used for biofuel production, such as biogas, and include residues from agriculture and forests, energy crops, and municipal and food waste. According to the latest statistical report for biogas, in Europe, almost 72% of the feedstocks used in the anaerobic digestion (AD) process for biogas production come from the agricultural sector, such as energy crops, manure, and other agricultural residues. The main issue of using lignocellulosic (LC) biomass for the biogas production is biomass recalcitrance, which represents biomass resistance to chemical and biological breakdown.
  • 5.0K
  • 17 Aug 2021
Topic Review
Solketal
Solketal (CAS 100–79–8) has low viscosity at room temperature (~11 cP) and freezing, boiling, and flash points of about −26 °C, 190 °C, and 80 °C, respectively. The density is 1.06 g/cm3 and the vapor pressure is 107.32 mmHg. It has low toxicity, slight odor, and it is non-irritant for humans; due to these characteristics and to the renewable origin, it is considered an environmentally friendly substance. It is completely miscible in water and in most organic compounds, which endows its solvent capacity.
  • 5.0K
  • 07 May 2021
Topic Review
Evolution of Digital Twins
A digital twin can be described as a digital replica of a real-world entity. It simulates the physical state and maybe the biological state and behavior of the real-world entity based on input data. It helps in predicting, optimizing, and improving decision making. It has revolutionized the industrial world, particularly the manufacturing industry, construction and healthcare sector, smart cities, and energy industry. 
  • 5.0K
  • 13 May 2021
Topic Review
Over the Shoulder Shot
The over the shoulder shot (OTS) is a camera angle used in film and television, where the camera is placed above the back of the shoulder and head of a subject. This shot is most commonly used to present conversational back and forth between two subjects. With the camera placed behind one character, the shot then frames the sequence from the perspective of that character. The over the shoulder shot is then utilised in a shot-reverse-shot sequence where both subject's OTS perspectives are edited consecutively to create a back and forth interplay, capturing dialogue and reactions. This inclusion of the back of the shoulder allows audiences to understand the spatial relationships between two subjects, while still being able to capture a closer shot of each subject’s facial expression. In film and television, the filmmaker or cinematographer’s choice of an OTS shot’s camera height, the use of focus and lenses affect the way audiences interpret subjects and their relationships to others and space.
  • 5.0K
  • 02 Dec 2022
Topic Review
Pathophysiology of Osteoporosis
Osteoporosis refers to excessive bone loss as reflected by the deterioration of bone mass and microarchitecture, which compromises bone strength. It is a complex multifactorial endocrine disease. Its pathogenesis relies on the presence of several endogenous and exogenous risk factors, which skew the physiological bone remodelling to a more catabolic process that results in net bone loss.
  • 5.0K
  • 15 Nov 2022
Topic Review
Applications of Nanocellulose/Nanocarbon Composites: Focus on Biotechnology and Medicine
Nanocellulose/nanocarbon composites are newly-emerging smart hybrid materials containing cellulose nanoparticles, such as nanofibrils and nanocrystals, and carbon nanoparticles, such as “classical” carbon allotropes (fullerenes, graphene, nanotubes and nanodiamonds), or other carbon nanostructures (carbon nanofibers, carbon quantum dots, activated carbon and carbon black). The nanocellulose component acts as a dispersing agent and homogeneously distribute the carbon nanoparticles in aqueous environment. Nanocellulose/nanocarbon composites can be prepared with many advantageous properties, such as high mechanical strength, flexibility, stretchability, tunable thermal and electrical conductivity, tunable optical transparency, photodynamic and photothermal activity, nanoporous character and high adsorption capacity. They are therefore promising for a wide range of industrial applications, such as energy generation, storage and conversion, water purification, food packaging, construction of fire retardants and shape memory devices. They also hold great promise for biomedical applications, such as radical scavenging, photodynamic and photothermal therapy of tumors and microbial infections, drug delivery, biosensorics, isolation of various biomolecules, electrical stimulation of damaged tissues (e.g. cardiac, neural), neural and bone tissue engineering, engineering of blood vessels and advanced wound dressing, e.g. with antimicrobial and antitumor activity. However, the potential cytotoxicity and immunogenicity of the composites and their components must also be taken into account.
  • 5.0K
  • 01 Nov 2020
Topic Review Peer Reviewed
Novel Bioactive Extraction and Nano-Encapsulation
An extraction technology works on the principle of two consecutive steps that involves mixture of solute with solvent and the movement of soluble compounds from the cell into the solvent and its consequent diffusion and extraction. The conventional extraction techniques are mostly based on the use of mild/high temperatures (50–90 °C) that can cause thermal degradation, are dependent on the mass transfer rate, being reflected on long extraction times, high costs, low extraction efficiency, with consequent low extraction yields. Due to these disadvantages, it is of interest to develop non-thermal extraction methods, such as microwave, ultrasounds, supercritical fluids (mostly using carbon dioxide, SC-CO2), and high hydrostatic pressure-assisted extractions which works on the phenomena of minimum heat exposure with reduced processing time, thereby minimizing the loss of bioactive compounds during extraction. Further, to improve the stability of these extracted compounds, nano-encapsulation is required. Nano-encapsulation is a process which forms a thin layer of protection against environmental degradation and retains the nutritional and functional qualities of bioactive compounds in nano-scale level capsules by employing fats, starches, dextrins, alginates, protein and lipid materials as encapsulation materials.
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  • 13 Apr 2022
Topic Review
Ascorbic Acid-Induced Reactions
Ascorbic acid is the most well-known vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis. Ascorbic acid can be used as a substrate or mediator in organic synthesis. In this review, we report ascorbic acid-catalyzed reactions in organic synthesis. Several examples are included in this review to demonstrate that ascorbic acid is a versatile catalyst for the synthesis of diverse organic compounds. Reactions catalyzed by ascorbic acid are performed in organic or aqueous media. The readily available and easy handling features of ascorbic acid make these procedures highly fascinating.
  • 5.0K
  • 25 Nov 2020
Topic Review
Dilophosaurus
Dilophosaurus (/daɪˌloʊfəˈsɔːrəs, -foʊ-/ dy-LOH-fə-SOR-əs, -⁠foh-) is a genus of theropod dinosaurs that lived in what is now North America during the Early Jurassic, about 193 million years ago. Three skeletons were discovered in northern Arizona in 1940, and the two best preserved were collected in 1942. The most complete specimen became the holotype of a new species in the genus Megalosaurus, named M. wetherilli by Samuel P. Welles in 1954. Welles found a larger skeleton belonging to the same species in 1964. Realizing it bore crests on its skull, he assigned the species to the new genus Dilophosaurus in 1970, as Dilophosaurus wetherilli. The genus name means "two-crested lizard", and the species name honors John Wetherill, a Navajo councilor. Further specimens have since been found, including an infant. Footprints have also been attributed to the animal, including resting traces. Another species, Dilophosaurus sinensis from China, was named in 1993, but was later found to belong to the genus Sinosaurus. At about 7 m (23 ft) in length, with a weight of about 400 kg (880 lb), Dilophosaurus was one of the earliest large predatory dinosaurs and the largest known land-animal in North America at the time. It was slender and lightly built, and the skull was proportionally large, but delicate. The snout was narrow, and the upper jaw had a gap or kink below the nostril. It had a pair of longitudinal, arched crests on its skull; their complete shape is unknown, but they were probably enlarged by keratin. The mandible was slender and delicate at the front, but deep at the back. The teeth were long, curved, thin, and compressed sideways. Those in the lower jaw were much smaller than those of the upper jaw. Most of the teeth had serrations at their front and back edges. The neck was long, and its vertebrae were hollow, and very light. The arms were powerful, with a long and slender upper arm bone. The hands had four fingers; the first was short but strong and bore a large claw, the two following fingers were longer and slenderer with smaller claws; the fourth was vestigial. The thigh bone was massive, the feet were stout, and the toes bore large claws. Dilophosaurus is a member of the family Dilophosauridae along with Dracovenator, a group placed between the Coelophysidae and later theropods. Dilophosaurus would have been active and bipedal, and may have hunted large animals; it could also have fed on smaller animals and fish. Due to the limited range of movement and shortness of the forelimbs, the mouth may instead have made first contact with prey. The function of the crests is unknown; they were too weak for battle, but may have been used in visual display, such as species recognition and sexual selection. It may have grown rapidly, attaining a growth rate of 30 to 35 kg (66 to 77 lb) per year early in life. The holotype specimen had multiple paleopathologies, including healed injuries and signs of a developmental anomaly. Dilophosaurus is known from the Kayenta Formation, and lived alongside dinosaurs such as Megapnosaurus and Sarahsaurus. Dilophosaurus was featured in the novel Jurassic Park and its movie adaptation, wherein it was given the fictional abilities to spit venom and expand a neck frill, as well as being smaller than the real animal. It was designated as the state dinosaur of Connecticut based on tracks found there.
  • 5.0K
  • 18 Oct 2022
Topic Review
Gastric Cancer Classification
Gastric cancer(GC) is the fourth most common cause of cancer-related mortalities worldwide. The incidence rate of GC rises progressively with age, the median age at diagnosis is 70 years. GC is a multifactorial disease, and both environmental and genetic factors have a role in its aetiology. Regarding the age of diagnosis, it is divided into early-onset gastric carcinoma (EOGC; 45 years or younger) and conventional GC (CGC; older than 45). EOGC relies mostly on genetic factors and therefore provides a unique model to study genetic alterations in GCs.
  • 5.0K
  • 27 Oct 2020
Topic Review
Electronic Trading
Electronic or scripless trading, sometimes called e-trading or paperless trading is a method of trading securities (such as stocks, and bonds), foreign exchange or financial derivatives electronically. Information technology is used to bring together buyers and sellers through an electronic trading platform and network to create virtual market places. They can include various exchange-based systems, such as NASDAQ, NYSE Arca and Globex, as well as other types of trading platforms, such as electronic communication networks (ECNs), alternative trading systems, crossing networks and "dark pools". Electronic trading is rapidly replacing human trading in global securities markets. Electronic trading is in contrast to older floor trading and phone trading and has a number of advantages, but glitches and cancelled trades do still occur.
  • 5.0K
  • 14 Oct 2022
Topic Review
Aircraft Livery
An aircraft livery is a set of comprehensive insignia comprising color, graphic, and typographical identifiers which operators (airlines, governments, Air force s and occasionally private and corporate owners) apply to their aircraft. As aircraft liveries evolved in the years after the Second World War, they became a leading subset of the emerging disciplines of corporate identity and branding and among the most prominent examples of fashion. They have provided an arena for the work of distinguished designers and eminent lay people like Raymond Loewy, Alexander Girard, and Jacqueline Kennedy Onassis. The term is an adaptation of the word livery: the uniform-style clothing worn by servants of wealthy families and government representatives until the early/mid-20th century. With the advent of stagecoaches, railway trains, and steamships, the term livery spread to their decoration. Since the 1950s, elements of airline liveries permeated ground vehicles, advertising, proprietary airport furniture, airline promotional materials and aircrew uniforms in an increasingly integrated manner, spreading to airline websites in the 1990s. Since the 1950s and 60s, aircraft liveries have usually been uniform livery across an entire fleet. One-off custom-designs might be applied from time to time to individual fleet members to highlight set occasions.
  • 5.0K
  • 21 Oct 2022
Topic Review
Odor Measurement Methods
Odor pollution related to industrial activities (e.g., chemical industries, oil and gas extraction and refining facilities, waste treatment and disposal facilities) is nowadays acknowledged as a serious environmental concern. Indeed, odors are currently subjected to control and regulation in many countries. Such regulations rely on the possibility of measuring odors. The methods that have been developed and standardized over the last years to measure odors, thereby including sensorial and instrumental techniques, are here described, thereby focusing on their applicability and limitations.
  • 5.0K
  • 08 Feb 2022
Topic Review
Fountain (Duchamp)
Fountain is a readymade sculpture produced by Marcel Duchamp in 1917: a porcelain urinal signed "R.Mutt". In April 1917, an ordinary piece of plumbing chosen by Duchamp was rotated 90 degrees on its axis and submitted for an exhibition of the Society of Independent Artists, the first annual exhibition by the Society to be staged at The Grand Central Palace in New York. Fountain was not rejected by the committee but it was removed from the show area, since Society rules stated that all works would be accepted from artists who paid the fee. Following that removal, Fountain was photographed at Alfred Stieglitz's studio, and the photo published in The Blind Man. The original has been lost. The work is regarded by art historians and theorists of the avant-garde as a major landmark in 20th-century art. Sixteen replicas were commissioned by Duchamp in the 1950s and 1960s and made to his approval. Some scholars have suggested that the original work was by a female artist rather than Duchamp, but this is a minority view among historians.
  • 5.0K
  • 28 Nov 2022
Topic Review
Spider Silk with Inorganic Nanomaterials
High-performance functional biomaterials are becoming increasingly requested. Numerous natural and artificial polymers have already demonstrated their ability to serve as a basis for bio-composites. Spider silk offers a unique combination of desirable aspects such as biocompatibility, extraordinary mechanical properties, and tunable biodegradability, which are superior to those of most natural and engineered materials. Modifying spider silk with various inorganic nanomaterials with specific properties has led to the development of the hybrid materials with improved functionality. The purpose of using these inorganic nanomaterials is primarily due to their chemical nature, enhanced by large surface areas and quantum size phenomena. Functional properties of nanoparticles can be implemented to macro-scale components to produce silk-based hybrid materials, while spider silk fibers can serve as a matrix to combine the benefits of the functional components. Therefore, it is not surprising that hybrid materials based on spider silk and inorganic nanomaterials are considered extremely promising for potentially attractive applications in various fields, from optics and photonics to tissue regeneration. This review summarizes and discusses evidence of the use of various kinds of inorganic compounds in spider silk modification intended for a multitude of applications. It also provides an insight into approaches for obtaining hybrid silk-based materials via 3D printing.
  • 5.0K
  • 29 Sep 2020
Topic Review
Cheese By-Products
Cheese whey (CW) is nowadays recognized as a source of functional and bioactive compounds, especially proteins and peptides. However, a large proportion of the whey produced worldwide is still not valorized. This results from the fact that small and medium size dairy industries lack dimension to make the necessary investments for CW valorization. In some countries such as Portugal, Spain, Italy and Turkey, CW is employed in the production of whey cheeses. The liquid remaining after whey cheese production represents more than 90% of the original whey and is called second cheese whey (SCW). SCW is a poorly studied by-product and there is little interest in its recovery. SCW is a poorly studied by-product and there is little interest in its recovery. Some authors studied the use of SCW for conversion into biofuel and as a biotechnological substrate for fermented products while others studied its potential for the production of fermented drinks. However, half of CW and almost all SCW are not valorized for human consumption. This review presents several alternatives for the valorization of both by-products.
  • 5.0K
  • 20 May 2021
Topic Review
Sorbent-Based Microextraction of Natural Toxins from Food Samples
Natural toxins are chemical substances that are not toxic to the organisms that produce them, but which can be a potential risk to human health when ingested through food. Thus, it is of high interest to develop advanced analytical methodologies to control the occurrence of these compounds in food products. Current trends in sample preparation involve moving towards “greener” approaches by scaling down analytical operations, miniaturizing the instruments and integrating new advanced materials as sorbents. The combination of these new materials with sorbent-based microextraction technologies enables the development of high-throughput sample preparation methods, which improve conventional extraction and clean-up procedures.
  • 5.0K
  • 05 Nov 2021
Topic Review Peer Reviewed
Age-Friendly Built Environment
Age-friendly built environments have been promoted by the World Health Organisation (WHO, Geneva, Switzerland) under the Global Age-friendly Cities (AFC) movement in which three domains are related to the built environment. These are: housing, transportation, outdoor spaces and public buildings. The aim is to foster active ageing by optimising opportunities for older adults to maximise their independent living ability and participate in their communities to enhance their quality of life and wellbeing. An age-friendly built environment is inclusive, accessible, respects individual needs and addresses the wide range of capacities across the course of life. Age-friendly housing promotes ageing in familiar surroundings and maintains social connections at the neighbourhood and community levels. Both age-friendly housing and buildings provide barrier-free provisions to minimise the needs for subsequent adaptations. Age-friendly public and outdoor spaces encourage older adults to spend time outside and engage with others against isolation and loneliness. Age-friendly public transport enables older adults to get around and enhances their mobility. For achieving an age-friendly living environment, a holistic approach is required to enable independent living, inclusion and active participation of older adults in society. The eight domains of the AFC movement are not mutually exclusive but overlap and support with one another.
  • 5.0K
  • 13 Apr 2022
Topic Review
False Vacuum
In quantum field theory, a false vacuum is a hypothetical vacuum that is somewhat, but not entirely, stable. It may last for a very long time in that state, and might eventually move to a more stable state. The most common suggestion of how such a change might happen is called bubble nucleation – if a small region of the universe by chance reached a more stable vacuum, this "bubble" (also called "bounce") would spread. A false vacuum exists at a local minimum of energy and is therefore not stable, in contrast to a true vacuum, which exists at a global minimum and is stable. It may be very long-lived, or metastable.
  • 5.0K
  • 24 Oct 2022
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