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Topic Review
Nap Pods
Nap pods also known as sleep pods, napping pods or nap capsules are special types of structures or chairs, often used in corporate/ workplace environments, hospitals and universities, that allow people to nap. Users use the pods to take private sleep breaks, often aided by technology and ambient features. Nap pods have emerged in corporate environments, hospitals, universities, airports and other public places. Their supposed efficacy is rooted in research that suggests that 20-minute naps could reduce signs of fatigue, boost energy levels, improve focus, boost productivity, improve mood, enhance learning, reduce stress and reduce the risk of cardiovascular disease.
  • 2.9K
  • 04 Nov 2022
Topic Review
Unmanned NASA Missions
Following is a sampling of some of NASA's past and present programs excluding manned spacecraft. The years in brackets are for first and latest launching. A program is a number of flights or missions with the same kind of spacecraft, therefore the name of the program and the name of the spacecraft used will often be the same. In all, NASA have made more than 1,000 unmanned missions into Earth orbit or beyond.
  • 2.9K
  • 23 Oct 2022
Topic Review
Biofouling on Stainless Steel
In humid environments, the formation of biofilms and microfouling are known to be the detrimental processes that first occur on stainless steel surfaces. This is known as biofouling. Subsequently, the conditions created by metabolites and the activity of organisms trigger corrosion of the metal and accelerate corrosion locally, causing a deterioration in, and alterations to, the performance of devices made of stainless steel. The microorganisms which thus affect stainless steel are mainly algae and bacteria.
  • 2.9K
  • 24 Feb 2022
Topic Review
Aflatoxins in Feed
Feeding farm animals with aflatoxin-contaminated feed can cause various severe toxic effects, leading to increased susceptibility to infectious diseases and increased mortality, weight loss, poor performance and reduced reproductive capability. Following ingestion of contaminated foodstuffs, aflatoxins are metabolized and biotransformed differently in animals. 
  • 2.9K
  • 16 Dec 2022
Topic Review
Supercritical Antisolvent Technique for the Preparation of Nanocatalysts
In an era where sustainability is becoming the main driving force for research and development, supercritical fluids-based techniques are presented as a very efficient alternative technology to conventional extraction, purification, and recrystallization processes. Supercritical antisolvent (SAS) precipitation is a novel technique that can replace liquid antisolvent precipitation techniques. Additionally, through the optimization of precipitation operating conditions, morphology, particle size, and particle size distribution of nanoparticles can be controlled. As an antisolvent, supercritical carbon dioxide (scCO2) is far more sustainable than its conventional liquid counterparts; not only does it have a critical point (304 K and 73.8 bar) on its phase diagram that allows for the precipitation processes to be developed so close to room temperature, but also its recovery and, consequently, the precipitated solute purification stage is considerably simpler. This technique can be used efficiently for preparing nanocatalysts to be used in biodiesel production processes.
  • 2.9K
  • 21 Dec 2022
Topic Review
Congenital Malformations in Sea Turtles
Congenital malformations can lead to embryonic mortality in many species, and sea turtles are no exception. Genetic and/or environmental alterations occur during early development in the embryo, and may produce aberrant phenotypes, many of which are incompatible with life. Causes of malformations are multifactorial; genetic factors may include mutations, chromosomal aberrations, and inbreeding effects, whereas non-genetic factors may include nutrition, hyperthermia, low moisture, radiation, and contamination. It is possible to monitor and control some of these factors (such as temperature and humidity) in nesting beaches, and toxic compounds in feeding areas, which can be transferred to the embryo through their lipophilic properties.
  • 2.9K
  • 22 Feb 2021
Topic Review
Chemistry of Essential Oils
The term essential oil was created in the 16th century and refers to the theory of “Quinta essentia” proposed by the famous German-Swiss alchemist and physician Paracelsus (1493–1541), born by Theophrastus Philippus Aureolus Bombastus von Hohenheim.
  • 2.9K
  • 13 Oct 2023
Topic Review
Hidden Jahn-Teller and Pseudo-Jahn-Teller effects
The source of spontaneous symmetry breaking (SSB) in polyatomic systems, attributed to the Jahn-Teller effect (in electronic degenerate states) or to the pseudo-Jahn-Teller effect (under the condition of pseudodegeneracy), is complemented with the notions of hidden Jahn-Teller effect (h-JTE) and hidden pseudo-Jahn-Teller effect (h-PJTE) to stand for the cases when neither electronic degeneracy, nor pseudodegeneracy is present, but the system is still spontaneously distorted. The h-JTE and h-PJTE occur due to, respectively, the JTE and PJTE in the excited states of the undistorted system, but being strong enough, they penetrate its ground state forming a stable configuration with lower symmetry and (possibly) different spin.
  • 2.9K
  • 12 Dec 2020
Topic Review
Prion
Prions are misfolded proteins that have the ability to transmit their misfolded shape onto normal variants of the same protein. They characterize several fatal and transmissible neurodegenerative diseases in humans and many other animals. It is not known what causes a normal protein to misfold, but the resulting abnormal three-dimensional structure confers infectious properties by collapsing nearby protein molecules into the same shape. The word prion is derived from the term, "proteinaceous infectious particle". In comparison to all other known infectious agents such as viroids, viruses, bacteria, fungi, and parasites, all of which contain nucleic acids (DNA, RNA, or both), the hypothesized role of a protein as an infectious agent stands in contrast. Prion isoforms of the prion protein (PrP), whose specific function is uncertain, are hypothesized as the cause of transmissible spongiform encephalopathies (TSEs), including scrapie in sheep, chronic wasting disease (CWD) in deer, bovine spongiform encephalopathy (BSE) in cattle (commonly known as "mad cow disease") and Creutzfeldt–Jakob disease (CJD) in humans. All known prion diseases in mammals affect the structure of the brain or other neural tissue; all are progressive, have no known effective treatment, and are always fatal. Until 2015, all known mammalian prion diseases were caused by the prion protein (PrP); however, in 2015 it was hypothesized that multiple system atrophy (MSA) was caused by a prion form of alpha-synuclein. Prions are a type of intrinsically disordered protein, which change their conformation unless they are bound to a specific partner such as another protein. With a prion, two protein chains are stabilized if one binds to another in the same conformation. The probability of this happening is low, but once it does the combination of the two is very stable. Then more units can get added, making a sort of "fibril". Prions form abnormal aggregates of proteins called amyloids, which accumulate in infected tissue and are associated with tissue damage and cell death. Amyloids are also responsible for several other neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. A prion disease is a type of proteopathy, or disease of structurally abnormal proteins. In humans, prions are believed to be the cause of Creutzfeldt–Jakob disease (CJD), its variant (vCJD), Gerstmann–Sträussler–Scheinker syndrome (GSS), fatal familial insomnia (FFI), and kuru. There is also evidence suggesting prions may play a part in the process of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS); these have been termed prion-like diseases. Several yeast proteins have also been identified as having prionogenic properties, as well as a protein involved in modification of synapses during the formation of memories (see Eric Kandel § Molecular changes during learning). Prion replication is subject to epimutation and natural selection just as for other forms of replication, and their structure varies slightly between species. Prion aggregates are stable, and this structural stability means that prions are resistant to denaturation by chemical and physical agents: they cannot be destroyed by ordinary disinfection or cooking. This makes disposal and containment of these particles difficult.
  • 2.9K
  • 14 Nov 2022
Topic Review
Kazakhstan’s Fisheries Sector
Kazakhstan, a former Soviet republic that is now independent, lies near the center of arid Eurasia. Its sparse hydrographic network includes a small number of large rivers, lakes, and reservoirs, many ponds and smaller streams, as well as littoral zones bordering the Caspian Sea and the Aral Sea. A diverse fisheries sector, initially based on wild fish capture and later including aquaculture, developed in these waters during the Soviet era, when animal agriculture was unable to meet the protein needs of Soviet citizens. The sector, which was originally centered on the Volga–Caspian basin, was tightly managed by Moscow and benefitted from coordinated investments in research, infrastructure, and human resources, as well as policies to increase the consumption of fish products. Independence in 1991 administered a political and economic shock that disrupted these relationships.
  • 2.9K
  • 07 May 2022
Topic Review
Mechanochemical Machines for Biorefining
Grinding and mechanical pretreatment are very popular methods utilized to enhance the reactivity of polymers and plant raw materials; however, the choice of devices and their modes of action is often performed through trial and error. An inadequate choice of equipment often results in inefficient grinding, low reactivity of the product, excess energy expenditure, and significant wear of the equipment.
  • 2.9K
  • 03 Dec 2020
Topic Review
Geoheritage
“Geoheritage” is a new term that assumes complete perception of Man for nature and the environment. As stated by McBriar “Geological-geomorphological heritage is the collection of geotopes, deposits, forms, and processes that comprise the geological history of each region, and the concept of preserving geological-geomorphological heritage is a cultural concept”.
  • 2.9K
  • 23 Sep 2021
Topic Review
Apple By-Product Valorisation
About 30% of the total production of apples is processed, being juice and cider the main resulting products. Regarding this procedure, a large quantity of apple by-product is generated, which tends to be undervalued, and commonly remains underutilised, landfilled, or incinerated. However, apple by-product is a proven source of bioactive compounds, namely dietary fibre, fatty acids, triterpenes, or polyphenols. Therefore, the application of green technologies should be considered in order to improve the functionality of apple by-product while promoting its use as the raw material of a novel product line. 
  • 2.9K
  • 03 Nov 2022
Topic Review
Humanitarian Logistics
Although logistics has been mostly utilized in commercial supply chains, it is also an important tool in disaster relief operations. Humanitarian logistics is a branch of logistics which specializes in organizing the delivery and warehousing of supplies during natural disasters or complex emergencies to the affected area and people. However, this definition focuses only on the physical flow of goods to final destinations, and in reality, humanitarian logistics is far more complicated and includes forecasting and optimizing resources, managing inventory, and exchanging information. Thus, a good broader definition of humanitarian logistics is the process of planning, implementing and controlling the efficient, cost-effective flow and storage of goods and materials, as well as related information, from the point of origin to the point of consumption for the purpose of alleviating the suffering of vulnerable people. This figure presents numerous important aspects in humanitarian logistics, including transport, inventory management, infrastructure, and communications.
  • 2.9K
  • 04 Nov 2022
Biography
Reginald Garrigou-Lagrange
Réginald Marie Garrigou-Lagrange OP (French: [gaʁigu lagʁɑ̃ʒ]; 21 February 1877 – 15 February 1964) was a French Catholic theologian and Dominican friar. He has been noted as a leading neo-Thomist of the 20th century, along with Jacobus Ramírez, Édouard Hugon, and Martin Grabmann.[1] He taught at the Dominican Pontifical University of St. Thomas Aquinas, the Angelicum, in Rome from 19
  • 2.9K
  • 28 Nov 2022
Topic Review
Skywell Shape in Huizhou Traditional Architecture
The skywell is a typical feature of Huizhou architecture and an important space; thus, there is the saying that “all halls are wells” . In traditional Huizhou architecture, the skywell, as a transition space between the interior and exterior, not only has positive significance for the lighting and ventilation of the building interior but also contains a lot of traditional Huizhou culture. Huizhou is famous for Huizhou merchants, who do not lack money and pay more attention to the construction of their own houses and the comfort and beauty of their houses; they set up skywells in their houses to acquire the aura of the “unity of heaven and man” and the pride of “standing on top of the sky”. On sunny days, the sun shines through the skywell to the front of the hall and the rooms, which means “sprinkling gold”; in rainy and snowy weather, rainwater flows down from the eaves around the skywell and sinks into the tank below the skywell, which means “flowing silver” and is a metaphor for wealth, also known as the “four waters to the hall”. In the skywell, combined with the through corridors and open halls, when the outdoor wind speed is high, wind pressure ventilation makes up the majority of the wind entering into the room from the skywell out, reducing the amount of indoor ventilation. When the outdoor wind is still, the skywell-shaped thermal pressure, which promotes indoor and outdoor ventilation, thus forms a complete ventilation system and plays the role of “hiding wind and gathering air”.
  • 2.9K
  • 30 May 2023
Topic Review
Marine Safety in Relation to Human Errors
As in any industry exposed to risk, human and organizational factors are the main stakes of maritime safety. Understanding the causes and risks of maritime accidents is integral to the sustainability of shipping. The investigation of marine accidents is a crucial tool for their identification in areas related to operations and ships.
  • 2.9K
  • 16 Jun 2023
Topic Review
September 2019 Climate Strikes
The September 2019 climate strikes, also known as the Global Week for Future, were a series of international strikes and protests to demand action be taken to address climate change, which took place from 20–27 September. The strikes' key dates were 20 September, which was three days before the United Nations Climate Summit, and 27 September. The protests took place across 4,500 locations in 150 countries. The event is a part of the school strike for climate movement, inspired by Swedish climate activist Greta Thunberg. The Guardian reported that roughly 6 million people participated in the events, whilst 350.org—a group that organised many of the protests—claim that 7.6 million people participated. The 20 September protests were likely the largest climate strikes in world history. Organisers reported that over 4 million people participated in strikes worldwide, including 1.4 million participants in Germany. An estimated 300,000 protesters took part in Australian strikes, a further 300,000 people joined UK protests and protesters in New York—where Greta Thunberg delivered a speech—numbered roughly 250,000. More than 2,000 scientists in 40 countries pledged to support the strikes. A second wave of protests took place on 27 September, in which an estimated 2 million people took part in over 2,400 protests. There were reported figures of one million protesters in Italy, and 170,000 people in New Zealand. In Montreal, where Greta Thunberg spoke, the Montreal school board cancelled classes for 114,000 of its students. Hundreds of thousands of people, including several federal party leaders, joined the march in Montreal.
  • 2.9K
  • 13 Oct 2022
Topic Review Peer Reviewed
Public School Choice Options in the United States
Under the structure of compulsory education, students in the United States are required to attend school until at least 16 years of age, which can be done at a variety of educational institutions, both public and private. Amongst public schools, students are each assigned a neighborhood school but also frequently have the option to attend a choice school. While the purpose of neighborhood schools is to provide a guaranteed educational option that accommodates most students, choice schools serve varied purposes that accommodate specific learning styles and societal goals. Four types of publicly funded choice schools are magnet, charter, alternative, and virtual schools. While each was established to serve a specific societal goal, their purposes have shifted over time and have produced varied student outcomes, both academic and non-academic.
  • 2.9K
  • 03 Jan 2024
Topic Review
Protoplasts
Plants are sessile organisms that have a remarkable developmental plasticity, which ensures their optimal adaptation to environmental stresses. Plant cell totipotency is an extreme example of such plasticity, whereby somatic cells have the potential to form plants via direct shoot organogenesis or somatic embryogenesis in response to various exogenous and/or endogenous signals. Protoplasts provide one of the most suitable systems for investigating molecular mechanisms of the plant cell totipotency, because they are effectively single cell populations. The term protoplast originates from the ancient Greek word prōtóplastos, which means “first-formed”, and refers to a cell without a cell wall. Protoplasts represent a powerful tool to study the mechanisms that induce cell proliferation from individual, differentiated somatic cells, enabling successful reprogramming of plant cells when cultured in vitro.
  • 2.9K
  • 26 Oct 2020
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