Hydrogen can be a promising clean energy carrier for the replenishment of non-renewable fossil fuels. The set back of hydrogen as an alternative fuel is due to its difficulties in feasible storage ...and safety concerns. Current hydrogen adsorption technologies, such as cryo-compressed and liquefied storage, are costly for practical applications. Metal-organic frameworks (MOFs) are crystalline materials that have structural versatility, high porosity and surface area, which can adsorb hydrogen efficiently. Hydrogen is adsorbed by physisorption on the MOFs through weak van der Waals force of attraction which can be easily desorbed by applying suitable heat or pressure. The strategies to improve the MOFs surface area, hydrogen uptake capacities and parameters affecting them are studied. Hydrogen spill over mechanism is found to provide high-density storage when compared to other mechanisms. MOFs can be used as proton exchange membranes to convert the stored hydrogen into electricity and can be used as electrodes for the fuel cells. In this review, we addressed the key strategies that could improve hydrogen storage properties for utilizing hydrogen as fuel and opportunities for further growth to meet energy demands.
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•The adsorption capacity of the hydrogen molecule in Metal-organic frameworks is discussed.•Different techniques to increase the storage capacity of MOFs is studied.•Mechanism of hydrogen adsorption on catalysts is discussed.•MOF composites have higher surface area when compared to pristine MOF.•MOFs with high storage capacity at ambient temperature can be used for energy storage.
The arginase enzyme developed in early life forms and was maintained during evolution. As the last step in the urea cycle, arginase cleaves l-arginine to form urea and l-ornithine. The urea cycle ...provides protection against excess ammonia, while l-ornithine is needed for cell proliferation, collagen formation, and other physiological functions. In mammals, increases in arginase activity have been linked to dysfunction and pathologies of the cardiovascular system, kidney, and central nervous system and also to dysfunction of the immune system and cancer. Two important aspects of the excessive activity of arginase may be involved in diseases. First, overly active arginase can reduce the supply of l-arginine needed for the production of nitric oxide (NO) by NO synthase. Second, too much l-ornithine can lead to structural problems in the vasculature, neuronal toxicity, and abnormal growth of tumor cells. Seminal studies have demonstrated that increased formation of reactive oxygen species and key inflammatory mediators promote this pathological elevation of arginase activity. Here, we review the involvement of arginase in diseases affecting the cardiovascular, renal, and central nervous system and cancer and discuss the value of therapies targeting the elevated activity of arginase.
Biopolymer, a natural biodegradable polymer has attracted much attention in recent years. Global environmental awareness and fossil fuel depletion urged researchers to work in the biopolymer field. ...Some of the biopolymers used for the fabrication of rechargeable batteries are cellulose, chitosan, pectin, agar-agar and carrageenan. An alternative energy storage system and also equivalent to lithium ion battery technology is also a need today due to the environmental impact and safety limitations concerning lithium materials. To fulfill all these needs, in the present work, magnesium ion conducting polymer electrolyte for battery applications was synthesized using Iota carrageenan and magnesium nitrate salt. One-gram Iota Carrageenan is complexed with various concentrations of magnesium nitrate salt by solution casting technique. XRD technique confirms the amorphous nature of film. FTIR confirms the complex formation between polymer and salt. DSC study was carried out to analyze the glass transition temperature. AC impedance spectroscopy was used to study the conductivity and dielectric properties of polymer electrolyte. One-gram I-Carrageenan with 0.4 wt% of Mg(NO3)2 has shown a maximum ionic conductivity of 6.1 × 10−4S/cm and it possess lowest activation energy value of 0.175 eV. A Primary battery was constructed using maximum conducting polymer electrolyte and its performance was studied.
•Polymer electrolyte membrane is synthesized using biopolymer I-Carrageenan and magnesium nitrate salt.•XRD studies confirms the amorphous nature of polymer electrolyte.•Using Impedance spectroscopy, conductivity values were calculated for polymer electrolytes.•Transference number is calculated for highest conducting polymer electrolyte.•Primary magnesium ion battery is constructed using highest conducting polymer electrolyte.
Our research demonstrates the effectiveness of fluorescence quenching between polyethyleneimine functionalised carbon dots (PEI-CDs) and cyclodextrin encapsulated ferrocene for fluorogenic detection ...of nitric oxide (NO). We confirmed that ferrocene can be used as a NO probe by observing its ability to quench the fluorescence emitted from PEI-CDs, with NO concentrations ranging from 1 × 10
M to 5 × 10
M. The photoluminescence intensity (PL) of PEI-CDs decreased linearly, with a detection limit of 500 nM. Previous studies have shown that ferrocene is a selective probe for NO detection in biological systems by electrochemical and colorimetric methods. The addition of fluorogenic NO detection using ferrocene as a probe enables the development of a three-way sensor probe for NO. Furthermore, the triple mode NO detection (electrochemical, colorimetric, and fluorogenic) with ferrocene aids in processing sensing data in a controlled manner similar to Boolean logic operations. This work presents key findings on the mechanism of fluorescence quenching between ferrocene hyponitrite intermediate and PEI-CDs, the potential of using ferrocene for triple channel NO detection as a single molecular entity, and the application of logic gates for NO sensing.
Human variant databases could be better exploited if the variant data available in multiple resources is integrated in a single comprehensive resource along with sequence and structural features. ...Such integration would improve the analyses of variants for disease prediction, prevention or treatment. The HuVarBase (HUmanVARiantdataBASE) assimilates publicly available human variant data at protein level and gene level into a comprehensive resource. Protein level data such as amino acid sequence, secondary structure of the mutant residue, domain, function, subcellular location and post-translational modification are integrated with gene level data such as gene name, chromosome number & genome position, DNA mutation, mutation type origin and rs ID number. Disease class has been added for the disease causing variants. The database is publicly available at https://www.iitm.ac.in/bioinfo/huvarbase. A total of 774,863 variant records, integrated in the HuVarBase, can be searched with options to display, visualize and download the results.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Successful renal transplantation is the optimal treatment for chronic kidney failure, but this was not always so for children. Beginning with the first kidney transplants in the 1950s, children ...experienced poorer patient and graft survival rates than adult patients. But over the last 6 decades, an improved understanding of the immune system which has steered pediatric multi-center clinical/pharmacokinetic and mechanistic studies that have sculpted our immunosuppression with markedly better patient and graft survivals. In addition, uniquely pediatric issues related to growth, development, neurocognitive maturation, increased complications from primary viral infections, and comorbid congenital/inherited disorders, are now diagnosed and effectively managed in these children. Refined pretransplant preparation (vaccinations for preventable diseases, attention to cognitive delays, effective dialysis and nutrition) improved donor selection, and more potent immunosuppression have all contributed to enhanced outcomes. Similarly, improvements in pediatric surgical techniques, postoperative care and better antiviral prophylaxis have all shortened hospitalizations and reduced morbidity. Today pediatric kidney transplant outcomes are markedly improved and younger children today experience better long-term graft survival than adults! While difficult problems remain, we have made tremendous progress and anticipate even more advances in the future of pediatric kidney transplantation.
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Loss of the blood-retinal barrier (BRB) integrity and subsequent damage to the neurovascular unit in the retina are the underlying reasons for diabetic retinopathy (DR). Damage to BRB ...eventually leads to severe visual impairment in the absence of prompt intervention. Diabetic macular edema and proliferative DR are the advanced stages of the disease where BRB integrity is altered. Primary mechanisms contributing to BRB dysfunction include loss of cell-cell barrier junctions, vascular endothelial growth factor, advanced glycation end products-induced damage, and oxidative stress. Although much is known about the involvement of adherens and tight-junction proteins in the regulation of vascular permeability in various diseases, there is a significant gap in our knowledge on the junctional proteins expressed in the BRB and how BRB function is modulated in the diabetic retina. In this review article, we present our current understanding of the molecular composition of BRB, the changes in the BRB junctional protein turnover in DR, and how BRB functional modulation affects vascular permeability and macular edema in the diabetic retina.
Vibration energy harvesting has gained tremendous attention in the past decade and continues to grow rapidly. There are various transduction mechanisms for converting the vibration energy into ...electrical energy, out of which the piezoelectric mechanism has been shown to provide advantages at the micro-to-meso scale. In the past few years, several studies have tried to address the question of which piezoelectric composition is better for energy harvesting; however, discussion on this subject continues. The intent of this letter is to provide an answer for this question through a simple criterion which can be used in routine material evaluation.
Texture analysis is a continuously evolving, noninvasive radiomics technique to quantify macroscopic tissue heterogeneity indirectly linked to microscopic tissue heterogeneity beyond human visual ...perception. In recent years, systemic oncologic applications of texture analysis have been increasingly explored. Here we discuss the basic concepts and methodologies of texture analysis, along with a review of various MR imaging texture analysis applications in glioma imaging. We also discuss MR imaging texture analysis limitations and the technical challenges that impede its widespread clinical implementation. With continued advancement in computational processing, MR imaging texture analysis could potentially develop into a valuable clinical tool in routine oncologic imaging.
Secure medical data transmission is the important criteria in tele-medicine. It is helpful for getting the exact medical information at the remote specialist’s side from the local doctor. The medical ...image watermarking technique is used for secure medical data transmission. Electronic patient record (EPR) is embedded within the original medical image to produce the watermarked medical image for protecting the patient information. The watermarked medical image visually looks like the original medical image. Hence the attacker visually knows the medical image transmission and easily attacks the system. To avoid this situation, image encryption technique is used to change the visual structure of the watermarked medical image. Normal image encryption gives the noise-like or texture-like unknown image format which indicates an existence of some secret information as the encrypted image. To overcome this problem, this paper proposed a visual medical image encryption technique to protect the existence of the watermarked medical image. And to ensure the source authentication, a biometric based authentication is also proposed. The watermarked medical image is encrypted using the proposed visually meaning full image encryption along with the fingerprint image. Experimental results prove that the proposed method yields good results and mitigate the attacker challenges.
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