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Topic Review
Taxonomy of Banksia
As with other flowering plants, the taxonomy of Banksia has traditionally been based on anatomical and morphological properties of the Banksia flower, fruiting structure and seed, along with secondary characteristics such as leaf structure and growth habit. Increasingly, molecular evidence from DNA is providing important new insights into relationships within the genus and between this and other genera in the Proteaceae. The genus is placed in family Proteaceae, subfamily Grevilleoideae, tribe Banksieae and subtribe Banksiinae. The most recent complete revision is that published in Alex George's 1999 monograph for the Flora of Australia book series; this recognises two subgenera, three sections, 13 series, 77 species, 6 subspecies and 18 varieties, and treats the traditionally related genus Dryandra as separate but closely related. Recent molecular cladistic analyses have provided an alternative view in which Dryandra is shown to be nested inside, and hence should be included within, Banksia. This interpretation has been controversial in some circles, and is not universally accepted.
  • 1.8K
  • 20 Oct 2022
Topic Review
Jeannette Expedition
The Jeannette Expedition of 1879–1881, officially called the U.S. Arctic Expedition, was an attempt led by George W. De Long to reach the North Pole by pioneering a route from the Pacific Ocean through the Bering Strait. The premise was that a temperate current, the Kuro Siwo, flowed northwards into the strait, providing a gateway to the Open Polar Sea and thus to the pole. This theory proved illusory; the expedition's ship, USS Jeannette and its crew of 33, was trapped by ice and drifted for nearly two years before she was crushed and sunk, north of the Siberian coast. De Long then led his 32 men on a perilous journey by sled, dragging the Jeannette's whaleboat and two cutters, eventually switching to these small boats to sail for the Lena Delta in Siberia. During this journey, and in the subsequent weeks of wandering in Siberia before rescue, 20 of the ship's complement died, including De Long. The chief exponent of the theory of a warm-water gateway to the North Pole was the German cartographer August Petermann. He encouraged James Gordon Bennett Jr., the proprietor of the New York Herald, to finance a polar expedition based on the untried Pacific route. Bennett acquired a former Royal Navy gunboat, the Pandora, and changed her name to Jeannette. De Long, whom Bennett chose to lead the expedition, was a serving naval officer with previous Arctic experience. Although essentially a private venture, in which Bennett paid all the bills, the expedition had the full support of the U.S. Government. Before departure the ship was commissioned into the U.S. Navy as USS Jeannette, and sailed under navy laws and discipline. Before its demise, the expedition discovered new islands—the De Long Islands—and collected valuable meteorological and oceanographic data. Although Jeannette's fate demolished the widely believed Open Polar Sea theory, the appearance in 1884 of debris from the wreck on the south-west coast of Greenland indicated the existence of an ocean current moving the permanent Arctic ice from east to west. This discovery inspired Fridtjof Nansen to mount his Fram expedition nine years later. A monument to the Jeannette's dead was erected at the United States Naval Academy in Annapolis, in 1890.
  • 1.8K
  • 01 Nov 2022
Topic Review
Residency
Residency or postgraduate training is specifically a stage of graduate medical education. It refers to a qualified physician (one who holds the degree of MD, DO, MBBS, MBChB), dentist (DDS or DMD) or podiatrist (DPM) who practices medicine, dentistry, or podiatry, respectively, usually in a hospital or clinic, under the direct or indirect supervision of a senior medical clinician registered in that specialty such as an attending physician or consultant. In many jurisdictions, successful completion of such training is a requirement in order to obtain an unrestricted license to practice medicine, and in particular a license to practice a chosen specialty. In the meantime they practice "on" the license of their supervising physician. An individual engaged in such training may be referred to as a resident, registrar or trainee depending on the jurisdiction. Residency training may be followed by fellowship or sub-specialty training. Whereas medical school teaches physicians a broad range of medical knowledge, basic clinical skills, and supervised experience practicing medicine in a variety of fields, medical residency gives in-depth training within a specific branch of medicine.
  • 1.8K
  • 06 Dec 2022
Topic Review
Biological Processes for Hydrogen Production
Hydrogen technology has great potential as a source of clean energy. The production of green hydrogen is a desirable and beneficial way to contribute to the decarbonization of the energy sector. In response to the demand for environmentally friendly and economically feasible approaches, biohydrogen production from waste materials has attracted interest. Waste materials from industrial or municipal production can be used as low-cost substrates for biohydrogen production through microbial degradation.
  • 1.8K
  • 13 Mar 2023
Topic Review
Wearable Neurofeedback Technologies
Neurofeedback, utilizing an electroencephalogram (EEG) and/or a functional near-infrared spectroscopy (fNIRS) device, is a real-time measurement of brain activity directed toward controlling and optimizing brain function. This treatment has often been attributed to improvements in disorders such as attention deficit hyperactivity disorder (ADHD), anxiety, depression, and epilepsy, among others.
  • 1.8K
  • 20 Oct 2023
Topic Review
Inflammatory Response of Dentine–Pulp Complex
Soft-tissue structures are in close interaction with mineralized bone, but also dentine, cementum and enamel of our teeth. These are exposed to intense mechanical and chemical stress as well as to dense microbiologic colonization. Teeth are susceptible to damage, most commonly to caries, where microorganisms from the oral cavity degrade the mineralized tissues of enamel and dentine and invade the soft connective tissue at the core, the dental pulp. However, the pulp is well-equipped to sense and fend off bacteria and their products and mounts various and intricate defense mechanisms. The front rank is formed by a layer of odontoblasts, which line the pulp chamber towards the dentine. These highly specialized cells not only form mineralized tissue but exert important functions as barrier cells. They recognize pathogens early in the process, secrete antibacterial compounds and neutralize bacterial toxins, initiate the immune response and alert other key players of the host defense. As bacteria get closer to the pulp, additional cell types of the pulp, including fibroblasts, stem and immune cells, but also vascular and neuronal networks, contribute with a variety of distinct defense mechanisms, and inflammatory response mechanisms are critical for tissue homeostasis. Still, without therapeutic intervention, a deep carious lesion may lead to tissue necrosis, which allows bacteria to populate the root canal system and invade the periradicular bone via the apical foramen at the root tip. The periodontal tissues and alveolar bone react to the insult with an inflammatory response, most commonly by the formation of an apical granuloma. Healing can occur after pathogen removal, which is achieved by disinfection and obturation of the pulp space by root canal treatment. 
  • 1.8K
  • 26 May 2021
Topic Review
Heme Biosynthesis
Heme biosynthesis is essential for almost all living organisms. Despite its conserved function, the pathway’s enzymes can be located in a remarkable diversity of cellular compartments in different organisms. This location does not always reflect their evolutionary origins, as might be expected from the history of their acquisition through endosymbiosis. Instead, the final subcellular localization of the enzyme reflects multiple factors, including evolutionary origin, demand for the product, availability of the substrate, and mechanism of pathway regulation. Chromera velia is a coral-associated alga bearing complex rhodophyte-derived plastid with a peculiar tetrapyrrole pathway. It synthesizes ALA using heterotrophic C4 path (same as apicomplexan parasites), which additionally supplies chlorophyll for photosystems. Using a combination of bioinformatics and experimental approaches, we investigated localizations of heme pathway enzymes in C. velia. Our data show that the pathway very likely starts in the mitochondrion, with the remaining enzymes located in the plastid. We demonstrate that the proteins are targeted to various cellular compartments by stringent translocon mechanisms that are not universal even for evolutionarily related organisms.
  • 1.8K
  • 08 Jul 2021
Topic Review
Toll-Like Receptor 4
Toll-like receptors (TLRs) are type I transmembrane glycoproteins belonging to the complex pattern recognition receptors (PRRs) expressed in immune and non-immune cells, including neurons and glia, which are involved in the regulation of innate immune and inflammatory responses. The TLR family comprises 11 members (TLR1–TLR11) in human and 12 (TLR1–TLR9, TLR11–TLR13) in mouse. TLR4 is one of the best characterized TLRs that surveys for the presence of structural motifs in a wide array of invading microorganisms, named pathogen-associated molecular patterns (PAMPs), and endogenous damage or danger molecular patterns (DAMPs), also known as alarmins, released by damaged cells and injured tissues or derived from apoptotic and necrotic cells. Activation of TLR4 induces the downstream start of inflammasome pathways which results in the release of a plethora of pro-inflammatory cytokines, Type I interferons (IFNs) and other inflammatory mediators.
  • 1.8K
  • 28 Mar 2023
Topic Review
Metal Additive Manufacturing for Satellites and Rockets
Additive manufacturing (AM), also called 3D printing, belongs to the emerging technologies of our time. After being used for rapid prototyping at the beginning, current rapid production is enabled for many applications due to increasingly improved technologies. One of the areas inh which additive manufacturing offers many advantages compared to conventional manufacturing techniques is space exploration, especially producing parts of satellites and rockets.
  • 1.8K
  • 20 Dec 2021
Topic Review
Implications of New Psychoactive Substances in Public Health
New psychoactive substances (NPS) aim to imitate the classical and controlled drugs, such as cannabis, cocaine, heroin, lysergic acid diethylamide (LSD), or methamphetamine. For this reason, they can be divided and classified into different categories or categorized according to their psychotropic effects or nature
  • 1.8K
  • 13 May 2022
Topic Review
Low-Functioning Autism
Low-functioning autism (LFA) is autism with low functioning levels. Symptoms may include impaired social communications or interactions, bizarre behavior, and lack of social or emotional reciprocity. Sleep problems, aggressiveness, and self-injurious behavior are also possible consequences. LFA is not a recognized diagnosis in the DSM-5 or ICD-10, neither of which subdivides autism based on intellectual capabilities. Synonyms include Kanner's syndrome, Kannerian autism and classic autism. The terms overlap with severe autism and profound autism (as opposed to "mild" or "moderate"), which may be vaguely defined and not necessarily correlate with severe and profound levels of intellectual disability (where profound is the most severe level).
  • 1.8K
  • 27 Oct 2022
Topic Review
Astrophysics Data System
The SAO/NASA Astrophysics Data System (ADS) is an online database of over 16 million astronomy and physics papers from both peer reviewed and non-peer reviewed sources. Abstracts are available free online for almost all articles, and full scanned articles are available in Graphics Interchange Format (GIF) and Portable Document Format (PDF) for older articles. It was developed by the National Aeronautics and Space Administration (NASA), and is managed by the Smithsonian Astrophysical Observatory. ADS is a powerful research tool and has had a significant impact on the efficiency of astronomical research since it was launched in 1992. Literature searches that previously would have taken days or weeks can now be carried out in seconds via the ADS search engine, which is custom-built for astronomical needs. Studies have found that the benefit to astronomy of the ADS is equivalent to several hundred million US dollars annually, and the system is estimated to have tripled the readership of astronomical journals. Use of ADS is almost universal among astronomers worldwide, and therefore ADS usage statistics can be used to analyze global trends in astronomical research. These studies have revealed that the amount of research an astronomer carries out is related to the per capita gross domestic product (GDP) of the country in which he/she is based, and that the number of astronomers in a country is proportional to the GDP of that country, so the total amount of research done in a country is proportional to the square of its GDP divided by its population.
  • 1.8K
  • 28 Oct 2022
Topic Review
Formic Acid as Liquid Carrier for H2 Storage
The development of low-carbon technologies that will facilitate the efficient use of hydrogen (H2) as an energy carrier is a critical requirement of contemporary society. To this end, it is anticipated that the cost of H2 production will become a key factor in tandem with production efficiency, process safety, and transport. Much effort has been made to create and develop new, reversible, and sustainable H2 storage systems. Among current techniques, formic acid (FA) has been identified as an efficient energy carrier for H2 storage. Numerous homogeneous catalysts based on transition metals with high activity and selectivity have been reported for selective FA dehydrogenation. 
  • 1.8K
  • 20 Apr 2023
Topic Review
Measure the Height of Mount Everest
Mount Everest is the highest mountain in the world. First, we should know where is Mt. Everest located on the plateau of Tibet map. It is on the border of Nepal and Tibet(the Autonomous Region of China). The determination of the height of Mount Everest(HME) is one of the focuses of the geodetic community. The shallow layer method (SLM) based on the definition of the geoid can determine the gravity field inside the shallow layer. The orthometric height of Mount Everest (HME) is calculated based on SLM, in which the key is to construct the shallow layer model. The top and bottom boundaries of the shallow layer model are the natural surface of the Earth and the surface at a certain depth below the reference geoid, respectively. 
  • 1.8K
  • 31 Jan 2024
Topic Review
Hydrogen Energy
This entry explains why the 'hydrogen economy' has been so slow in coming, despite the abundance of hydrogen (H2) on Earth. H2 is either bound up with oxygen in water, or with carbon in fossil fuels, which release CO2 on combustion. For several decades, hydrogen-powered vehicles using fuel cells were seen as the major opportunity for H2. But if H2 is produced from fossil fuels, its use makes little contribution to climate change mitigation, and in any case, electric vehicles are now the main challengers to oil for powering transport. H2 will only come into its own when intermittent renewable energy, mainly wind and solar energy, dominate energy supply, as it makes sense to convert surplus power to H2 for storage or immediate use.  
  • 1.8K
  • 04 Jan 2021
Topic Review
Upcycling of Brewers' Spent Grains
Brewers' spent grains (BSGs) are the most important by-product of the brewing industry and are rich in protein and fiber. However, abundant amounts of BSGs are discarded annually worldwide. This project aimed to employ and compare innovative drying techniques to introduce snacks with protein sources derived from leftover BSGs. This study explored the dehydration kinetics of BSGs and the effect of three different drying methods—oven drying (OD), freeze drying (FD), and vacuum microwave drying (VMD)—on their protein content and functionality. Then, an energy and exergy analysis for the drying methods was given. Accordingly, a snack product (baked chips) using the dehydrated BSGs was developed by a sensory panel study to assess consumer acceptability of the final products. It was found that the VMD process took less drying time (48 min) compared to OD (50 min), with higher effectiveness as a drying process. VMD-treated BSG also showed moderate protein functionality and the highest overall acceptability when used in baked chips. Thus, VMD might be used as a sustainable drying technology for thermal treatment and valorization of BSG. In addition to having implications for dietary health, findings can help improve the economy of the breweries and other industries that deal with the processing of grains by valorizing their process waste and contributing to sustainability.
  • 1.8K
  • 28 Oct 2020
Topic Review
Tourism Marketing
This piece will focus on how tourism marketing could better place focus on local food and drink, to attract visitors interested in authenticity, and engender in them a deeper sense of place with their vacation destination.
  • 1.8K
  • 30 Oct 2020
Topic Review
From CO2 to Value-Added Products
The global warming and the dangerous climate change arising from the massive emission of CO2 from the burning of fossil fuels have motivated the search for alternative clean and sustainable energy sources. However, the industrial development and population necessities make the decoupling of economic growth from fossil fuels unimaginable and, consequently, the capture and conversion of CO2 to fuels seems to be, nowadays, one of the most promising and attractive solutions in a world with high energy demand. In this respect, the electrochemical CO2 conversion using renewable electricity provides a promising solution. However, faradaic efficiency of common electro-catalysts is low, and therefore, the design of highly selective, energy-efficient, and cost-effective electrocatalysts is critical. Carbon-based materials present some advantages such as relatively low cost and renewability, excellent electrical conductivity, and tunable textural and chemical surface, which show them as competitive materials for the electro-reduction of CO2.
  • 1.8K
  • 23 Mar 2021
Topic Review
TIGIT
TIGIT is a transmembrane glycoprotein comprising one immunoglobulin variable (IgV) domain, a type I transmembrane domain, and a cytoplasmic tail with an immunoreceptor tyrosine-based inhibitory motif (ITIM) and immunoglobulin tyrosine tail (ITT)-like motif.
  • 1.8K
  • 08 Apr 2021
Topic Review
Silicon Nitride
Silicon nitride is a ceramic material with unique properties. These properties strongly encourage the use of monolithic silicon nitride and coatings as contemporary and future biomaterial for a variety of medical applications including spinal, orthopedic and dental implants, bone grafts and scaffolds, platforms for intelligent synthetic neural circuits, antibacterial and antiviral particles and coatings, optical biosensors, and nano-photonic waveguides for sophisticated medical diagnostic devices.
  • 1.8K
  • 17 May 2021
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