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Topic Review
High-Temperature PEM Fuel Cells
This review summarizes the current status, operating principles, and recent advances in high-temperature polymer electrolyte membranes (HT-PEMs), with a particular focus on the recent developments, technical challenges and commercial prospects of the HT-PEM fuel cells. A detailed review of the most recent research activities has been covered by this work, with a major focus on the state-of-the-art concepts describing the proton conductivity and degradation mechanisms of HT-PEMs. Also, the fuel cell performance and the lifetime of HT-PEM fuel cells as a function of operating conditions have been discussed. In addition, the review will highlight the important outcomes found in recent literature about the HT-PEM fuel cell. The main objectives of this review paper will be as follows: (1) the latest development of the HT-PEMs, primarily based on polybenzimidazole membranes, (2) the latest development of the fuel cell performance and the lifetime of the HT-PEMs.
  • 1.8K
  • 28 Aug 2021
Topic Review
Risk Factors of Rejection in Renal Transplant Recipients
Kidney transplantation (KTx) is the treatment of choice for end-stage renal diseases (ESRD). Multiple factors influence graft rejection after KTx. Pre-operative factors affecting graft function and survival include donor and recipient characteristics such as age, gender, race, and immunologic compatibility. In addition, several peri- and post-operative parameters affect graft function and rejection, such as cold and warm ischemia times, and post-operative immunosuppressive treatment. Exposure to non-self-human leucocyte antigens (HLAs) prior to transplantation up-regulates the recipient’s immune system. A higher rate of acute rejection is observed in transplant recipients with a history of pregnancies or significant exposure to blood products because these patients have higher panel reactive antibody (PRA) levels. Identifying these risk factors will help physicians to reduce the risk of allograft rejection, thereby promoting graft survival. 
  • 1.8K
  • 18 Mar 2022
Topic Review
Hyperpolarization
Hyperpolarization is the nuclear spin polarization of a material in a magnetic field far beyond thermal equilibrium conditions determined by the Boltzmann distribution. It can be applied to gases such as 129Xe and 3He, and small molecules where the polarization levels can be enhanced by a factor of 104-105 above thermal equilibrium levels. Hyperpolarized noble gases are typically used in magnetic resonance imaging (MRI) of the lungs. Hyperpolarized small molecules are typically used for in vivo metabolic imaging. For example, a hyperpolarized metabolite can be injected into animals or patients and the metabolic conversion can be tracked in real-time. Other applications include determining the function of the neutron spin-structures by scattering polarized electrons from a very polarized target (3He), surface interaction studies, and neutron polarizing experiments.
  • 1.8K
  • 03 Nov 2022
Topic Review
Bowmouth Guitarfish
The bowmouth guitarfish (Rhina ancylostoma), also called the shark ray or mud skate, is a species of ray and a member of the family Rhinidae. Its evolutionary affinities are not fully resolved, though it may be related to true guitarfishes and skates. This rare species occurs widely in the tropical coastal waters of the western Indo-Pacific, at depths of up to 90 m (300 ft). Highly distinctive in appearance, the bowmouth guitarfish has a wide and thick body with a rounded snout and large shark-like dorsal and tail fins. Its mouth forms a W-shaped undulating line, and there are multiple thorny ridges over its head and back. It has a dorsal color pattern of many white spots over a bluish gray to brown background, with a pair of prominent black markings over the pectoral fins. This large species can reach a length of 2.7 m (8.9 ft) and weight of 135 kg (298 lb). Usually found near the sea floor, the bowmouth guitarfish prefers sandy or muddy areas near underwater structures. It is a strong-swimming predator of bony fishes, crustaceans, and molluscs. This species gives live birth to litters of two to eleven pups, which are nourished during gestation by yolk. The International Union for Conservation of Nature (IUCN) has assessed the bowmouth guitarfish as Vulnerable because it is widely caught by artisanal and commercial fisheries for its valuable fins and meat. It is viewed as a nuisance by trawlers, however, because its bulk and thorny skin cause it to damage netted catches. Habitat degradation and destruction pose an additional, significant challenge to this ray's survival. The bowmouth guitarfish adapts well to captivity and is displayed in public aquariums.
  • 1.8K
  • 09 Nov 2022
Topic Review
DAvE (Infineon)
DAVE (Infineon) Digital Application Virtual Engineer (DAVE), is a C/C++-language software development and code generation tool for microcontroller applications. DAVE is a standalone system with automatic code generation modules. It is suited for the development of software drivers for Infineon microcontrollers and aids the developer with automatically created C-level templates and user desired functionalities. Latest releases of DAVE include all required parts to develop code, compile and debug on the target for free (based on the ARM GCC toolsuite). Together with several low-cost development boards one can get involved in microcontroller design very easy. This makes Infineon microcontroller products also more usable to small companies and to home-use / DIY projects - similar to established products of Atmel (AVR, SAM) and Microchip (PIC, PIC32) to name a few. DAVE was developed by Infineon Technologies. Therefore, the automatic code generator supports only Infineon microcontrollers. The user also has to get used to the concept of the Eclipse IDE. The generated code can be also used on other (often non-free) development environments from Keil, Tasking and so on.
  • 1.8K
  • 15 Nov 2022
Topic Review
BRCA Mutation
A BRCA mutation is a mutation in either of the BRCA1 and BRCA2 genes, which are tumour suppressor genes. Hundreds of different types of mutations in these genes have been identified, some of which have been determined to be harmful, while others have no proven impact. Harmful mutations in these genes may produce a hereditary breast–ovarian cancer syndrome in affected persons. Only 5–10% of breast cancer cases in women are attributed to BRCA1 and BRCA2 mutations (with BRCA1 mutations being slightly more common than BRCA2 mutations), but the impact on women with the gene mutation is more profound. Women with harmful mutations in either BRCA1 or BRCA2 have a risk of breast cancer that is about five times the normal risk, and a risk of ovarian cancer that is about ten to thirty times normal. The risk of breast and ovarian cancer is higher for women with a high-risk BRCA1 mutation than with a BRCA2 mutation. Having a high-risk mutation does not guarantee that the woman will develop any type of cancer, or imply that any cancer that appears was actually caused by the mutation, rather than some other factor. High-risk mutations, which disable an important error-free DNA repair process (homology directed repair), significantly increase the person's risk of developing breast cancer, ovarian cancer and certain other cancers. Why BRCA1 and BRCA2 mutations lead preferentially to cancers of the breast and ovary is not known, but lack of BRCA1 function seems to lead to non-functional X-chromosome inactivation. Not all mutations are high-risk; some appear to be harmless variations. The cancer risk associated with any given mutation varies significantly and depends on the exact type and location of the mutation and possibly other individual factors. Mutations can be inherited from either parent and may be passed on to both sons and daughters. Each child of a genetic carrier, regardless of sex, has a 50% chance of inheriting the mutated gene from the parent who carries the mutation. As a result, half of the people with BRCA gene mutations are male, who would then pass the mutation on to 50% of their offspring, male or female. The risk of BRCA-related breast cancers for men with the mutation is higher than for other men, but still low. However, BRCA mutations can increase the risk of other cancers, such as colon cancer, pancreatic cancer, and prostate cancer. Methods to diagnose the likelihood of a patient with mutations in BRCA1 and BRCA2 getting cancer were covered by patents owned or controlled by Myriad Genetics. Myriad's business model of exclusively offering the diagnostic test led to Myriad growing from being a startup in 1994 to being a publicly traded company with 1200 employees and about $500M in annual revenue in 2012; it also led to controversy over high prices and the inability to get second opinions from other diagnostic labs, which in turn led to the landmark Association for Molecular Pathology v. Myriad Genetics lawsuit.
  • 1.8K
  • 01 Dec 2022
Topic Review
Probiotics for Neurodegenerative Diseases
Neurodegenerative disorders (ND) are a group of conditions that affect the neurons in the brain and spinal cord, leading to their degeneration and eventually causing the loss of function in the affected areas. These disorders can be caused by a range of factors, including genetics, environmental factors, and lifestyle choices. Major pathological signs of these diseases are protein misfolding, proteosomal dysfunction, aggregation, inadequate degradation, oxidative stress, free radical formation, mitochondrial dysfunctions, impaired bioenergetics, DNA damage, fragmentation of Golgi apparatus neurons, disruption of axonal transport, dysfunction of neurotrophins (NTFs), neuroinflammatory or neuroimmune processes, and neurohumoral symptoms. According to studies, defects or imbalances in gut microbiota can directly lead to neurological disorders through the gut-brain axis. Probiotics in ND are recommended to prevent cognitive dysfunction, which is a major symptom of these diseases. 
  • 1.8K
  • 28 Apr 2023
Topic Review Peer Reviewed
Balanced Scorecard: History, Implementation, and Impact
The Balanced Scorecard (BSC) is a strategic management framework introduced by Kaplan and Norton in 1992 to address the limitations of traditional performance measurement systems. It integrates financial and non-financial performance measures across four perspectives—financial, customer, internal processes, and learning and growth. Over three decades, the BSC has evolved into a comprehensive strategic tool adopted across industries and sectors worldwide. While its adaptability and integrative approach are strengths, criticisms include challenges in implementation, assumed cause–effect relationships, and relevance in decentralized organizations. Future research should investigate cultural adaptation; the incorporation of environmental, social, and governance metrics; and advancements driven by artificial intelligence to maintain ongoing relevance.
  • 1.8K
  • 25 Mar 2025
Topic Review
Glycosylation
Post-translational modifications are one way that biomineral-associated cells control the function and fate of proteins. Of the ten different types of post-translational modifications, one of the most interesting and complex is glycosylation, or the covalent attachment of carbohydrates to amino acid sidechains Asn, Ser, and Thr of proteins. There are several biomineral-associated glycoproteins that have been characterized, and a subset of these have been the subject of intensive in vitro experimentation.  These studies indicate that glycosylation does not alter the inherent function of the biomineralization protein; rather, it either accentuates or attenuates protein functionality. In essence, glycosylation gives the cell the “last word” as to what degree a biomineralization protein will participate in the biomineralization process.
  • 1.8K
  • 25 Sep 2020
Topic Review
TiO2-Based Nanostructures for Microbial Inactivation
Pathogenic microorganisms can spread throughout the world population, as the current COVID-19 pandemic has dramatically demonstrated. In this scenario, a protection against pathogens and other microorganisms can come from the use of photoactive materials as antimicrobial agents able to hinder, or at least limit, their spreading by means of photocatalytically assisted processes activated by light—possibly sunlight—promoting the formation of reactive oxygen species (ROS) that can kill microorganisms in different matrices such as water or different surfaces without affecting human health. Here, we focus the attention on TiO2 nanoparticle-based antimicrobial materials, intending to provide an overview of the most promising synthetic techniques, toward possible large-scale production, critically review the capability of such materials to promote pathogen (i.e., bacteria, virus, and fungi) inactivation, and, finally, take a look at selected technological applications.
  • 1.8K
  • 08 Dec 2020
Topic Review
CIPA
Congenital insensitivity to pain with anhidrosis (CIPA) has two characteristic features: the inability to feel pain and temperature, and decreased or absent sweating (anhidrosis). This condition is also known as hereditary sensory and autonomic neuropathy type IV. The signs and symptoms of CIPA appear early, usually at birth or during infancy, but with careful medical attention, affected individuals can live into adulthood.
  • 1.8K
  • 04 Jan 2021
Topic Review
Homogeneous charge compression ignition (HCCI)
Homogeneous charge compression ignition (HCCI) is considered an advanced combustion method for internal combustion engines that offers simultaneous reductions in oxides of nitrogen (NOx) emissions and increased fuel efficiency. The present study examines the influence of intake air temperature (IAT) and premixed diesel fuel on fuel self-ignition characteristics in a light-duty compression ignition engine. Partial HCCI was achieved by port injection of the diesel fuel through air-assisted injection while sustaining direct diesel fuel injection into the cylinder for initiating combustion. The self-ignition of diesel fuel under such a set-up was studied with variations in premixed ratios (0–0.60) and inlet temperatures (40–100 °C) under a constant 1600 rpm engine speed with 20 Nm load. 
  • 1.8K
  • 23 Aug 2021
Topic Review
Invasion of African Clarias gariepinus in Bangladesh
The African catfish Clarias gariepinus has been introduced for aquaculture in Bangladesh due to the scarcity of indigenous C. batrachus fingerlings. The African catfish Clarias gariepinus is a highly carnivorous species and predates small indigenous freshwater fishes when escaping into natural water bodies. However, the government of Bangladesh has banned the farming of C. gariepinus due to the carnivorous nature of this species. The introduction of C. gariepinus caused native biodiversity loss due to its predatory nature.
  • 1.8K
  • 25 Feb 2022
Topic Review
Radar Depth and Velocity Estimation
Radar can measure range and Doppler velocity, but both of them cannot be directly used for downstream tasks. The range measurements are sparse and therefore difficult to associate with their visual correspondences. The Doppler velocity is measured in the radial axis and, therefore, cannot be directly used for tracking.
  • 1.8K
  • 08 Jun 2022
Topic Review
Endangered Species Recovery Plan
An endangered species recovery plan, also known as a species recovery plan, species action plan, species conservation action, or simply recovery plan, is a document describing the current status, threats and intended methods for increasing rare and endangered species population sizes. Recovery plans act as a foundation from which to build a conservation effort to preserve animals which are under threat of extinction.
  • 1.8K
  • 11 Oct 2022
Topic Review
Multiphysics
Multiphysics is defined as the coupled processes or systems involving more than one simultaneously occurring physical field and the studies of and knowledge about these processes and systems. As an interdisciplinary study area, multiphysics spans over many science and engineering disciplines. Multiphysics is a practice built on mathematics, physics, application, and numerical analysis. The mathematics involved usually contains partial differential equations and tensor analysis. The physics refers to common types of physical processes, e.g., heat transfer (thermo-), pore water movement (hydro-), concentration field (concentro or diffuso/convecto/advecto), stress and strain (mechano-), dynamics (dyno-), chemical reactions (chemo- or chemico-), electrostatics (electro-), neutronics (neutro-), and magnetostatics (magneto-).
  • 1.8K
  • 12 Oct 2022
Topic Review
Alsophila Dealbata
Alsophila dealbata, synonym Cyathea dealbata, commonly known as the silver fern or silver tree-fern, or as ponga /ˈpɒŋə/ or punga /ˈpʌŋə/ (from Māori kaponga or ponga), is a species of medium-sized tree fern, endemic to New Zealand. The fern is usually recognisable by the silver-white colour of the under-surface of mature fronds. It is a symbol commonly associated with the country both overseas and by New Zealanders themselves.
  • 1.8K
  • 02 Nov 2022
Topic Review
Utility of Chinese Versions of Addenbrooke’s Cognitive Examination
Addenbrooke’s cognitive examination (ACE) is a cognitive screening tool that has developed through three stages: ACE, ACE-Revised (ACE-R), and ACE-Ⅲ. In addition, mini-Addenbrooke’s Cognitive Examination (M-ACE) and ACE mobile are the additional versions that is derived from ACE-III. ACE and its related versions show better performance than Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) in detecting mild cognitive impairment in different neurological disorders. It has been translated into numerous languages, including Chinese.
  • 1.8K
  • 11 Nov 2022
Topic Review
AI-Based Cyber-Attack Detection and Mitigation in Microgrids
With the inclusion of communication networks and smart metering devices, the attack surface has increased in microgrids, making them vulnerable to various cyber-attacks. The negative impact of such attacks may render the microgrids out-of-service, and the attacks may propagate throughout the network due to the absence of efficient mitigation approaches. AI-based techniques are being employed to tackle such data-driven cyber-attacks due to their exceptional pattern recognition and learning capabilities. AI-based methods for cyber-attack detection and mitigation that address the cyber-attacks in microgrids are summarized. 
  • 1.8K
  • 22 Nov 2023
Topic Review
Natural Biomolecules in Sperm Production
Poor semen quality and abnormal sperm structure or function by and large constitute a predominant presentation of male infertility and are among the major reasons why couples seek the services of assisted reproduction. Natural biomolecules, such as polyphenols or flavonoids have garnered substantial attention from the scientific community as well as public media. In the meantime, it has been suggested that administration of natural biomolecules has been shown to have a positive impact male infertility. A number of in vivo as well as in vitro studies have reported that active components isolated from natural resources could enhance blood circulation in the male reproductive system and support the synthesis and secretion of androgens. Animal and human reports also suggest that natural biomolecules may play important roles in the enhancement of semen quality, including sperm concentration, motility, vitality, and structural integrity. 
  • 1.8K
  • 23 Sep 2021
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