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Topic Review
DO-254
RTCA DO-254 / EUROCAE ED-80, Design Assurance Guidance for Airborne Electronic Hardware is a document providing guidance for the development of airborne electronic hardware, published by RTCA, Incorporated and EUROCAE. The DO-254/ED-80 standard was formally recognized by the FAA in 2005 via AC 20-152 as a means of compliance for the design assurance of electronic hardware in airborne systems. The guidance in this document is applicable, but not limited, to such electronic hardware items as The document classifies electronic hardware items into simple or complex categories. An item is simple "if a comprehensive combination of deterministic tests and analyses appropriate to the design assurance level can ensure correct functional performance under all foreseeable operating conditions with no anomalous behavior." Conversely, a complex item is one that cannot have correct functional performance ensured by tests and analyses alone; so, assurance must be accomplished by additional means. The body of DO-254/ED-80 establishes objectives and activities for the systematic design assurance of complex electronic hardware, generally presumed to be complex custom micro-coded components, as listed above. However, simple electronic hardware is within the scope of DO-254/ED-80 and applicants propose and use the guidance in this standard to obtain certification approval of simple custom micro-coded components, especially devices that support higher level (A/B) aircraft functions. The DO-254/ED-80 standard is the counterpart to the well-established software standard RTCA DO-178C/EUROCAE ED-12C. With DO-254/ED-80, the certification authorities have indicated that avionics equipment contains both hardware and software, and each is critical to safe operation of aircraft. There are five levels of compliance, A through E, which depend on the effect a failure of the hardware will have on the operation of the aircraft. Level A is the most stringent, defined as "catastrophic" effect (e.g., loss of the aircraft), while a failure of Level E hardware will not affect the safety of the aircraft. Meeting Level A compliance for complex electronic hardware requires a much higher level of verification and validation than Level E compliance.
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  • 14 Oct 2022
Topic Review
Four-day Week
A four-day week, or a compressed work schedule, is an arrangement where a workplace or school has its employees or students work or attend school over the course of four days per week rather than the more customary five. This arrangement can be a part of flexible working hours, and is sometimes used to cut costs, as seen in the example of the so-called "4/10 work week," where employees work a normal 40 hours across four days, i.e. a "four-ten" week. However, a four-day week can also be a fixed work schedule. More modest attempts to enact a 32-hour workweek (a four-day week and an eight-hour day combined) have remained elusive in the following 80 years despite pockets of residual support.
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  • 16 Nov 2022
Topic Review
Isthmin Protein Family
Isthmin (ISM) is a secreted protein family with two members, namely ISM1 and ISM2, both containing a TSR1 domain followed by an AMOP domain. Its broad expression pattern suggests diverse functions in developmental and physiological processes. Multiple studies have focused on the functional analysis of the ISM protein family in several events, including angiogenesis, metabolism, organ homeostasis, immunity, craniofacial development, and cancer.
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  • 06 Jan 2023
Topic Review
Advanced Drug Delivery for Treating Sjögren’s Dry Eye
Sjögren’s syndrome is a chronic and insidious autoimmune disease characterized by lymphocyte infiltration of exocrine glands. Patients typically present with dry eye (keratoconjunctivitis sicca), dry mouth (xerostomia), and other systemic manifestations. The current management for Sjögren's syndrome dry eye (SSDE) has been ineffective as it only targets ocular surface inflammation and dryness without addressing the specific disease process. Ophthalmologists often adopt a trial-and-error approach, which allows the cycle of dry eye disease (DED) to progress and potentially cause permanent damage to the lacrimal functional unit. Topical treatments also depend on patients' ability to administer eye drops and their compliance. These limitations emphasize the need for personalized, targeted treatments that address the underlying pathophysiology of SSDE. This article aims to present new advances in ocular drug delivery for more effective treatment.
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  • 10 Feb 2023
Topic Review Video
Graph Burning
The graph burning problem is a relatively new combinatorial optimization problem that helps quantify a graph's vulnerability. It is defined in terms of a fundamental diffusion model.
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  • 21 Jul 2023
Topic Review
Entrepreneurship Education in Higher Education
Entrepreneurship education, as an emerging scientific field, has undergone significant evolution at the conceptual and praxis levels. The concept of entrepreneurship was considered from a broad perspective as the capacity to act upon opportunities and ideas, thereby creating social, cultural, or financial value in diverse contexts. The study and cultivation of this competence are highly relevant to enhancing employability and equipping young people with the skills, knowledge, and attitudes necessary within an entrepreneurial culture for the exercise of active citizenship. 
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  • 20 Sep 2023
Topic Review
Metabolism of Acetic Acid Bacteria
Vinegar is one of the most appreciated fermented foods in European and Asian countries. In industry, its elaboration depends on numerous factors, including the nature of starter culture and raw material, as well as the production system and operational conditions. Furthermore, vinegar is obtained by the action of acetic acid bacteria (AAB) on an alcoholic medium in which ethanol is transformed into acetic acid. Besides the highlighted oxidative metabolism of AAB, their versatility and metabolic adaptability make them a taxonomic group with several biotechnological uses.
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  • 25 Oct 2023
Topic Review
Cell-Penetrating Peptides
Cell-penetrating peptides (CPPs) comprise a class of short polypeptides that possess the ability to selectively interact with the cytoplasmic membrane of certain cell types, translocate across plasma membranes and accumulate in the cell cytoplasm, organelles (e.g., the nucleus and mitochondria), and other subcellular compartments. CPPs are either of natural origin or de novo designed and synthesized from segments and patches of larger proteins or designed by algorithms. With such intrinsic characteristics, along with membrane permeation, translocation, and cellular uptake properties, CPPs can intracellularly convey diverse substances and nanomaterials, such as hydrophilic organic compounds and drugs, macromolecules (nucleic acids and proteins), nanoparticles (nanocrystals and polyplexes), metals and radionuclides, which can be covalently attached via CPP N- and C-terminals or through the preparation of CPP complexes. A cumulative number of studies on animal toxins, primarily isolated from the venom of arthropods and snakes, have revealed the cell-penetrating activities of venom peptides and toxins, which can be harnessed for application in biomedicine and pharmaceutical biotechnology.
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  • 12 Mar 2021
Topic Review
Autism Care and Intervention Based on Mobile Apps
The mobile apps can be categorized into autism support apps, educational apps, teacher training apps, parental support apps, and data collection apps. The individuals with autism spectrum disorder (ASD) are the primary users of the first two categories of apps. Teachers of children with ASD are the primary users of the teacher training apps. Parents are the primary users of the parental support apps, while individuals with ASD are usually the primary users of the data collection apps and clinicians and autism researchers are the beneficiaries. Gamification, virtual reality, and autism-specific mechanisms have been used to improve the usability of the apps. User-centered design is the most popular approach for mobile app development. Augmentative and alternative communication, video modeling, and various behavior change practices have been used as the theoretical foundation for intervention efficacy.
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  • 19 Sep 2023
Topic Review
ALSP
Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) is a neurological condition characterized by changes to certain areas of the brain. A hallmark of ALSP is leukoencephalopathy, which is the alteration of a type of brain tissue called white matter. White matter consists of nerve fibers (axons) covered by a substance called myelin that insulates and protects them. The axons extend from nerve cells (neurons) and transmit nerve impulses throughout the body. Areas of damage to this brain tissue (white matter lesions) can be seen with magnetic resonance imaging (MRI). Another feature of ALSP is swellings called spheroids in the axons of the brain, which are a sign of axon damage. Also common in ALSP are abnormally pigmented glial cells. Glial cells are specialized brain cells that protect and maintain neurons. Damage to myelin and neurons is thought to contribute to many of the neurological signs and symptoms in people with ALSP.
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  • 04 Jan 2021
Topic Review
Autophagy and Alzheimer’s Disease
Alzheimer’s disease (AD) is characterized by the formation of intracellular aggregate composed of heavily phosphorylated tau protein and extracellular deposit of amyloid-β (Aβ) plaques derived from proteolysis cleavage of amyloid precursor protein (APP). Autophagy refers to the lysosomal-mediated degradation of cytoplasmic constituents, which plays a critical role in maintaining cellular homeostasis. Importantly, recent studies reported that dysregulation of autophagy is associated in the pathogenesis of AD, and therefore, autophagy modulation has gained attention as a promising approach to treat AD pathogenesis. In AD, both the maturation of autolysosomes and its retrograde transports have been obstructed, which causes the accumulation of autophagic vacuoles and eventually leads to degenerating and dystrophic neurites function. However, the mechanism of autophagy modulation in APP processing and its pathogenesis have not yet been fully elucidated in AD. In the early stage of AD, APP processing and Aβ accumulation-mediated autophagy facilitate the removal of toxic protein aggregates via mTOR-dependent and -independent pathways. In addition, a number of autophagy-related genes (Atg) and APP are thought to influence the development of AD, providing a bidirectional link between autophagy and AD pathology.
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  • 28 Sep 2021
Topic Review
Acanthamoeba spp.
Acanthamoeba spp. are free-living amoebas, which are widely distributed in soil, water, and air. They are capable of causing granulomatous amebic encephalitis, Acanthamoeba pneumonia, Acanthamoeba keratitis, and disseminated acanthamoebiasis.
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  • 18 Mar 2021
Topic Review
Hybrid Renewable Energy Systems
According to literature, around 80% of the world’s total energy demand is supplied either through fuel-based sources such as oil, gas, and coal or through nuclear-based sources. Literature also shows that a shortage of fossil fuels is inevitable and the world will face this problem sooner or later. Moreover, the remote and rural areas that suffer from not being able to reach traditional grid power electricity need alternative sources of energy. A “hybrid-renewable-energy system” (HRES) involving different renewable resources can be used to supply sustainable power in these areas. The uncertain nature of renewable energy resources and the intelligent ability of the neural network approach to process complex time series inputs have inspired the use of ANN methods in renewable energy forecasting. 
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  • 11 May 2021
Topic Review
Aphid–Plant–Phytovirus Pathosystems
Aphids are responsible for the spread of more than half of the known phytovirus species. Virus transmission within the plant–aphid–phytovirus pathosystem depends on vector mobility which allows the aphid to reach its host plant and on vector efficiency in terms of ability to transmit phytoviruses.
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  • 11 Jun 2021
Topic Review
Semantic Support of Cultural Heritage
The usage of semantics is not new in cultural heritage disciplines. They are commonly used to define standards for meta-, para-, and provenance information for documenting and archiving. Examples of such standards are LIDO and MIDAS Heritage. These XML schema standards are still used in cultural heritage. In recent years, however, the emergence of the Semantic Web has provided the much-required boost to semantic frameworks and technologies. It also dictates how semantics are defined and used today. Techniques and tools that formalize semantics through formalized knowledge representations have become the norm in different fields applying semantics.
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  • 23 Jun 2021
Topic Review
Liposomal Cytarabine
Cancer is the second leading cause of death worldwide. The main modality to fight against cancer is surgery, radiotherapy, and chemotherapy, and more recently targeted therapy, gene therapy and immunotherapy, which play important roles in treating cancer patients. In the last decades, chemotherapy has been well developed. Nonetheless, administration of the drug is not always successful, as limited drug dosage can reach the tumor cells.. In this context, the possibility to use an encapsulated anti-cancer drug may potentially solve the problem. Liposomal cytarabine is a formulation with pronounced effectiveness in lymphomatous meningitis and reduced cardiotoxicity if compared to liposomal anthracyclines. Thus, the future liposomal cytarabine use could be extended to other diseases given its reduction in cytotoxic side effects compared to the free formulation. 
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  • 22 Jul 2021
Topic Review
2D Materials in Ultrafast Lasers
Ultrafast lasers are the key component of ultrafast photonics, which have come into practice in various fields, such as micromachining, communication, medical procedures, gas detection, and remote sensing. With the advantages of stability, compactness, and easy implementation, mode-locking and Q-switching are two notable techniques to achieve ultrafast pulsed lasers, where SAs perform crucial roles in many types of ultrafast lasers, such as fiber, solid-state, and waveguide lasers.
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  • 25 Aug 2021
Topic Review
Applications of AMPs in Packaging
Antimicrobial Peptides can be defined as the molecules of the innate immune system present in all life forms, ranging from bacteria to human beings. The innate immune system is a defence system working non-specifically against injury or infection in the barrier surface. AMPs are composed of a sequence of amino acid ranging from 5 to 50 chains, usually L-amino acids.
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  • 13 Aug 2021
Topic Review
Wine Cooperatives in Germany
According to the German cooperative law, cooperatives are defined as “associations of a non-closed number of members whose purpose is to promote their members’ income and business or their social or cultural interests through joint business operations” (GenG §1). In Germany, the following actors can become members of a cooperative: physical persons, commercial partnerships (in German: Personengesellschaften des Handelsrechts), legal entities under private and public law. Cooperatives represent a horizontal cooperation among producers.
  • 1.4K
  • 25 Nov 2021
Topic Review
DNA-Based Animal Species Authentication in Dairy Products
Milk is one of the most important nutritious foods, widely consumed worldwide, either in its natural form or via dairy products. Currently, several economic, health and ethical issues emphasize the need for a more frequent and rigorous quality control of dairy products and the importance of detecting adulterations in these products. For this reason, several conventional and advanced techniques have been proposed, aiming at detecting and quantifying eventual adulterations, preferentially in a rapid, cost-effective, easy to implement, sensitive and specific way. DNA-based methods relying on polymerase chain reaction (PCR) have been widely applied to detect adulterations in foods from both plant and animal origins, including dairy products because of their simplicity, high sensitivity and high specificity. They benefit from the high thermal stability of DNA molecules, which is particularly relevant when analysing processed foods, and are independent from immunochemical recognition, making them not susceptible to cross-reactivity. The ubiquity of nucleic acids in every type of cell and particularity in healthy mammary glands, which have high numbers of leucocytes and epithelial cells that are transferred to the milk, is another advantage to highlight. During cheese making, these cells are concentrated and allow the isolation of DNA to discriminate the species.
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  • 28 Apr 2022
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