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Topic Review
Bluetooth 5.1
Bluetooth 5.1 allows producers to create location applications based on the Angle of Departure (AoD) and the Angle of Arrival (AoA). Accordingly, it is conceivable to design proper Indoor Positioning Systems (IPS), for instance, for the traceability of resources, assets, and people.
  • 2.3K
  • 02 Jun 2021
Topic Review
Brazil’s Formal E-Waste Recycling System
Disruptive innovation has led to the increased obsolescence and accelerated replacement of electrical and electronic equipment, resulting in the rapid growth of waste electrical and electronic equipment (e-waste) worldwide. However, amidst the challenges in e-waste management, the recovery of secondary raw materials from e-waste presents an attractive business opportunity.
  • 2.3K
  • 16 Jan 2024
Topic Review
Scalable Synthesis of Mesoporous TiO2
Increasing environmental concern, related to pollution and clean energy demand, have urged the development of new smart solutions profiting from nanotechnology, including the renowned nanomaterial-assisted photocatalytic degradation of pollutants. In this framework, increasing efforts are devoted to the development of TiO2-based nanomaterials with improved photocatalytic activity. A plethora of synthesis routes to obtain high quality TiO2-based nanomaterials is currently available. Nonetheless, large-scale production and the application of nanosized TiO2 is still hampered by technological issues and the high cost related to the capability to obtain TiO2 nanoparticles with high reaction yield and adequate morphological and structural control. 
  • 2.3K
  • 26 Jul 2021
Topic Review
The Jahn-Teller Effects
The fundamental property of a polyatomic system to undergo spontaneous symmetry breaking was first formulated by L. Landau in 1934 as follows: the configuration of any nonlinear polyatomic system in a degenerate electronic state undergoes spontaneous distortions that remove the degeneracy. This groundbreaking idea, appended with proof, was published by H. Jahn and E. Teller, resulting in what is presently known as the Jahn-Teller effect (JTE). Since then, many extensions of this groundbreaking idea were revealed and developed. Presently, four types of electronic structures that lead to spontaneous symmetry breaking are revealed: in addition to electronic degeneracy resulting in the proper Jahn-Teller effect, two or more close in energy (pseudodegenerate) electronic states may lead to similar instability and distortions, called the pseudo-JTE (PJTE), and the same spontaneous distortion effects may take place when there is neither degeneracy, nor pseudodegeneracy in the fground state of the high-symmetry configuration, but a strong JTE or pseudo-JTE take place in a low-lying excited state, that penetrates the ground state, distorting the system; these are the hidden -JTE and hidden-PJTE, respectively.
  • 2.3K
  • 26 Oct 2021
Topic Review
Value Innovation
Value innovation, as defined by Kim and Mauborgne, and Kim and Mauborgne, is making “the competition irrelevant by offering fundamentally new and superior buyer value in existing markets and by enabling a quantum leap in buyer value to create new markets”. The concept of value innovation is a summation of analytical outcomes from 150 strategic moves spanning more than 30 companies, worldwide, in approximately 30 industries, as well as a study for the business launched of approximately 100 companies to quantify the influence of value innovation on a company’s growth in revenues and profits. From a company perspective, Mohanty, Mele, Mele, Russo Spenaviewed value innovation as resource integration and superior competency development; meanwhile, Setijonodescribed value innovation as “creating stakeholder value through radical (disruptive)-attractive quality”, where the logic behind it is to provide a total solution, extraordinary experiences, and cost reduction through product, service, and delivery platforms.
  • 2.3K
  • 26 Oct 2021
Topic Review
Disability Studies
Disability studies is an academic discipline that examines the meaning, nature, and consequences of disability. Initially, the field focused on the division between "impairment" and "disability", where impairment was an impairment of an individual's mind or body, while disability was considered a social construct. This premise gave rise to two distinct models of disability: the social and medical models of disability. In 1999 the social model was universally accepted as the model preferred by the field. However, in recent years, the division between the social and medical models has been challenged. Additionally, there has been an increased focus on interdisciplinary research. For example, recent investigations suggest using "cross-sectional markers of stratification" may help provide new insights on the non-random distribution of risk factors capable of acerbating disablement processes.[clarification needed] Disability studies courses include work in disability history, theory, legislation, policy, ethics, and the arts. However, students are taught to focus on the lived experiences of individuals with disabilities in practical terms. The field is focused on increasing individuals with disabilities access to civil rights and improving their quality of life. Disability studies emerged in the 1980s primarily in the US, the UK, and Canada. In 1986, the Section[clarification needed] for the Study of Chronic Illness, Impairment, and Disability of the Social Science Association (United States) was renamed the Society for Disability Studies. The first US disabilities studies program emerged in 1994, at Syracuse University. The first edition of the Disabilities Studies Reader (one of the first collections of academic papers related to disability studies) was published in 1997. The field grew rapidly over the next ten years. In 2005, the Modern Language Association established disability studies as a "division of study". While Disability Studies primarily emerged in the US, the UK and Canada, disability studies were also conducted in other countries through different lens. For instance Germany, looks at Queer Disability Studies since the beginning of the early 20th century. The Disability Studies in Germany are influenced by the written literary works of feminist sexologist who study how being disabled affects one's sexuality and ability to feel pleasure. In Norway, Disability Studies are focused in the literary context. A variation emerged in 2017 with the first Accessibility Studies program at Central Washington Univeristy with an interdisciplinary focus on social justice, universal design and international Web Accessibility Guidelines (WAG3) as a general education knowledge base.
  • 2.3K
  • 14 Nov 2022
Topic Review
Old Quantum Theory
The old quantum theory is a collection of results from the years 1900–1925 which predate modern quantum mechanics. The theory was never complete or self-consistent, but was rather a set of heuristic corrections to classical mechanics. The theory is now understood as the semi-classical approximation to modern quantum mechanics. The main and final accomplishments of the old quantum theory were the determination of the modern form of the periodic table by Edmund Stoner and the Pauli Exclusion Principle which were both premised on the Arnold Sommerfeld enhancements to the Bohr model of the atom. The main tool of the old quantum theory was the Bohr–Sommerfeld quantization condition, a procedure for selecting out certain states of a classical system as allowed states: the system can then only exist in one of the allowed states and not in any other state.
  • 2.3K
  • 22 Nov 2022
Topic Review
Ciguatoxins in Fish
Ciguatoxins are very potent marine neurotoxins, that accumulate to toxic levels in edible fish in certain circumtropical areas, and are associated with ciguatera fish poisoning worldwide. Ciguatoxins are produced by specific benthic dinoflagellates, enter the marine food chain via herbivorous fish and invertebrates, and eventual are biotransformed in herbivorous, omnivorous, and carnivorous fishes to more poisonous forms. Ciguatoxins cause risks to human health at very low concentrations. To decrease the risk of ciguatera fish poisoning, it is important to know fishing areas with low concentrations of ciguatoxins, as well as to test fish tissue for toxins before consumption. Modern laboratories use several detection techniques, such as mouse bioassay, cell-based assays, receptor-binding assays, antibody-based immunoassays, electrochemical methods, and analytical techniques, to obtain information about the total toxicity of fish tissue samples, as well as to identify toxins and to determine the toxin profile. State-of-the-art ciguatoxin detection involves the combination of a cell-based assay or receptor-binding assay to screen total toxicity, and liquid chromatography coupled with mass spectrometry to confirm toxins and provide toxin profiles. 
  • 2.3K
  • 25 Aug 2020
Topic Review
Traditional Bulgarian Dairy Products
Dairy products are nutritionally indispensable, consumed daily and one of the most desired foods by a large part of the world population. 
  • 2.3K
  • 01 Jun 2021
Topic Review
Ballasted Track
Ballasted track has the phenomenon of local instabilities, which are usually related to the intensive sleeper void development that requires enormous maintenance costs and influences track reliability, availability and safety. The appearance of the void zones is unavoidable in such structures as transition zones, turnouts and rail joints. 
  • 2.3K
  • 19 Jul 2021
Topic Review
Path Planning Technique for Mobile Robots
Mobile robot path planning involves designing optimal routes from starting points to destinations within specific environmental conditions. Even though there are well-established autonomous navigation solutions, it is worth noting that comprehensive, systematically differentiated examinations of the critical technologies underpinning both single-robot and multi-robot path planning are notably scarce. These technologies encompass aspects such as environmental modeling, criteria for evaluating path quality, the techniques employed in path planning and so on.
  • 2.3K
  • 19 Jan 2024
Topic Review
High-Capacity Ni-Rich Cathode Materials for Lithium-Ion Batteries
Lithium-ion batteries are undoubtedly known as the most promising rechargeable batteries. Ternary Ni-rich Li[NixCoyMnz]O2 and Li[NixCoyAlz]O2 cathode materials stand as the ideal candidate for a cathode active material to achieve high capacity and energy density, low manufacturing cost, and high operating voltage.
  • 2.3K
  • 19 Feb 2024
Topic Review
Additive Manufacturing Processes
Additive manufacturing (AM, 3D printing) is used in many fields and different industries. In the medical and dental field, every patient is unique and, therefore, AM has significant potential in personalized and customized solutions. This text explores what additive manufacturing processes and materials are utilized in medical and dental applications, especially focusing on processes that are less commonly used. The processes are categorized in ISO/ASTM process classes: powder bed fusion, material extrusion, VAT photopolymerization, material jetting, binder jetting, sheet lamination and directed energy deposition combined with classification of medical applications of AM. Based on the findings, it seems that directed energy deposition is utilized rarely only in implants and sheet lamination rarely for medical models or phantoms. Powder bed fusion, material extrusion and VAT photopolymerization are utilized in all categories. Material jetting is not used for implants and biomanufacturing, and binder jetting is not utilized for tools, instruments and parts for medical devices. The most common materials are thermoplastics, photopolymers and metals such as titanium alloys. If standard terminology of AM would be followed, this would allow a more systematic review of the utilization of different AM processes.
  • 2.3K
  • 09 Apr 2021
Topic Review
Beta-3 Adrenergic Receptor
The beta-3 adrenergic receptor (β3-AR) is by far the least studied isotype of the beta-adrenergic sub-family. Despite its study being long hampered by the lack of suitable animal and cellular models and inter-species differences, a substantial body of literature on the subject has built up in the last three decades and the physiology of β3-AR is unraveling quickly. As will become evident in this work, β3-AR is emerging as an appealing target for novel pharmacological approaches in several clinical areas involving metabolic, cardiovascular, urinary, and ocular disease.
  • 2.3K
  • 05 May 2022
Topic Review
Fault-tolerant Computer System
Fault-tolerant computer systems are systems designed around the concepts of fault tolerance. In essence, they must be able to continue working to a level of satisfaction in the presence of errors or breakdowns. Fault tolerance is not just a property of individual machines; it may also characterise the rules by which they interact. For example, the Transmission Control Protocol (TCP) is designed to allow reliable two-way communication in a packet-switched network, even in the presence of communications links which are imperfect or overloaded. It does this by requiring the endpoints of the communication to expect packet loss, duplication, reordering and corruption, so that these conditions do not damage data integrity, and only reduce throughput by a proportional amount. Recovery from errors in fault-tolerant systems can be characterised as either 'roll-forward' or 'roll-back'. When the system detects that it has made an error, roll-forward recovery takes the system state at that time and corrects it, to be able to move forward. Roll-back recovery reverts the system state back to some earlier, correct version, for example using checkpointing, and moves forward from there. Roll-back recovery requires that the operations between the checkpoint and the detected erroneous state can be made idempotent. Some systems make use of both roll-forward and roll-back recovery for different errors or different parts of one error.
  • 2.3K
  • 09 Nov 2022
Topic Review
ICANN
The Internet Corporation for Assigned Names and Numbers (ICANN /ˈaɪkæn/ EYE-kan) is an American multistakeholder group and nonprofit organization responsible for coordinating the maintenance and procedures of several databases related to the namespaces and numerical spaces of the Internet, ensuring the network's stable and secure operation. ICANN performs the actual technical maintenance work of the Central Internet Address pools and DNS root zone registries pursuant to the Internet Assigned Numbers Authority (IANA) function contract. The contract regarding the IANA stewardship functions between ICANN and the National Telecommunications and Information Administration (NTIA) of the United States Department of Commerce ended on October 1, 2016, formally transitioning the functions to the global multistakeholder community. Much of its work has concerned the Internet's global Domain Name System (DNS), including policy development for internationalization of the DNS system, introduction of new generic top-level domains (TLDs), and the operation of root name servers. The numbering facilities ICANN manages include the Internet Protocol address spaces for IPv4 and IPv6, and assignment of address blocks to regional Internet registries. ICANN also maintains registries of Internet Protocol identifiers. ICANN's primary principles of operation have been described as helping preserve the operational stability of the Internet; to promote competition; to achieve broad representation of the global Internet community; and to develop policies appropriate to its mission through bottom-up, consensus-based processes. ICANN's creation was announced publicly on September 17, 1998, and it formally came into being on September 30, 1998, incorporated in the U.S. state of California. Originally headquartered in Marina del Rey in the same building as the University of Southern California's Information Sciences Institute (ISI), its offices are now in the Playa Vista neighborhood of Los Angeles in Facebook's old office.
  • 2.3K
  • 10 Nov 2022
Topic Review
Beech Marten
The Beech Marten (Martes foina) is a slender and agile carnivore native to Europe and parts of Asia. With its distinctive cream-colored throat patch and bushy tail, this medium-sized mustelid is known for its adaptability to various habitats, including forests, woodlands, and urban areas. As a versatile predator, the Beech Marten preys on a variety of small mammals, birds, insects, and fruits, playing a vital role in ecosystem dynamics across its range.
  • 2.3K
  • 15 Mar 2024
Topic Review
Project Alpha
Project Alpha was an effort by magician James Randi to test the quality of scientific rigor of a well-known test of paranormal phenomena. In the late 1970s, Randi contacted the newly established McDonnell Laboratory for Psychical Research ("MacLab") with suggestions on how to conduct tests for paranormal phenomena. At the same time, two teenage boys (Steve Shaw, later known as Banachek, and Mike Edwards) independently contacted the McDonnell Laboratory and volenteered as subjects for such tests from 1979 to 1982. They quickly proved to exhibit a range of paranormal abilities far and away better than the other subjects of the experiment. The lab began leaking reports of the pair's capabilities, which were in fact simple magic tricks. When rumors of the test subjects' connection to Randi reached Peter Phillips, head of the MacLab, he instituted tighter protocols for the experiments; the two subjects' results declined sharply. In 1983, Randi held a press conference to expose the deception In the wake of Project Alpha, there were a number of controversies about the ethics of interference in scientific research and the validity of paranormal research as it then existed. It remains a watershed event in the field of parapsychology.
  • 2.3K
  • 28 Nov 2022
Topic Review
Extrusion Bioprinting for Skin Applications
Skin is a large and complex organ that serves protective and regulatory functions and is responsible for communication between the external environment and the inner organism. To fulfill these functions, skin has evolved as an organ with a complex anatomy derived from both the ectoderm (epidermis) and mesoderm (dermis). The skin includes not only these two major compartments but also important appendages, including hair follicles, sweat and sebaceous glands, nerve endings, and blood vessels, all of which have intricate spatial arrangements that render fabrication of the full skin organ challenging.
  • 2.3K
  • 26 Oct 2020
Topic Review
Chitosan
Chitosan is a random copolymer comprising d-glucosamine (the deacetylated ones) and N-acetyl-d-glucosamine units.
  • 2.3K
  • 12 Apr 2021
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