Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines (guidelines) with recommendations to ...improve cardiovascular health. These guidelines, which are based on systematic methods to evaluate and classify evidence, provide a cornerstone for quality cardiovascular care. The ACC and AHA sponsor the development and publication of guidelines without commercial support, and members of each organization volunteer their time to the writing and review efforts. Guidelines are official policy of the ACC and AHA.
Abstract Since the first description of apical hypertrophic cardiomyopathy in Japan 40 years ago, contrasting information from all over the world has emerged regarding the natural history of the ...disease. This review provides an overview of incidence, phenotypic expressions, clinical features, prognosis, and management of this heterogeneous clinical entity, which may play a more relevant role in the burden of sudden cardiac death than previously thought.
4-aminophenol (4-AP) is one of the major environmental pollutants which is broadly exploited as drug intermediate in the pharmaceutical formulations. The extensive release of 4-AP in the environment ...without treatment has become a serious issue that has led several health effects on humans. This work describe the determination of 4-AP through a new chemically modified sensor based on polyvinyl alcohol functionalized tungsten oxide/reduced graphene oxide (PVA/WO3/rGO) nanocomposite. The fabricated nanocomposite was characterized through XRD and HR-TEM to confirm the crystalline structure with average size of 35.9 nm and 2D texture with ultra-fine sheets. The electrochemical characterization of fabricated sensor was carried out by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) to ensure the charge transfer kinetics of modified sensor that revealed high conductivity of PVA/WO3/rGO/GCE. Under optimized conditions e.g. scan rate 80 mV/s, phosphate buffer (pH 6) as supporting electrolyte and potential window from −0.2 to 0.8 V, the prepared sensor showed excellent response for 4-AP. The linear dynamic range of developed method was optimized as 0.003–70 μM. The LOD of fabricated sensor based on PVA/WO3/rGO/GCE for 4-AP was calculated as 0.51 nM. The practical application of PVA/WO3/rGO/GCE was tested in real water and pharmaceutical samples. The fabricated sensor presented here, exhibited exceptional stability and sensitivity than the reported sensors and could be effectively used for the monitoring 4-AP without interferences.
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•Fabrication of graphene oxide (GO) through hammer's method.•Synthesis of tungsten oxide/reduced graphene oxide by exploiting polyvinyl alcohol as functionalizing agent.•Utilization of PVA/WO3/rGO nanocomposite as chemically modified material for the quantification of 4-aminophenol.•Electrochemical characterization of bare and modified electrodes through CV and EIS.•Quantification of 4-aminophenol in real water and pharmaceutical samples.
Several corona viral infections have created serious threats in the last couple of decades claiming the death of thousands of human beings. Recently, corona viral epidemic raised the issue of ...developing effective antiviral agents at the earliest to prevent further losses. Natural products have always played a crucial role in drug development process against various diseases, which resulted in screening of such agents to combat emergent mutants of corona virus. This review focuses on those natural compounds that showed promising results against corona viruses. Although inhibition of viral replication is often considered as a general mechanism for antiviral activity of most of the natural products, studies have shown that some natural products can interact with key viral proteins that are associated with virulence. In this context, some of the natural products have antiviral activity in the nanomolar concentration (e.g., lycorine, homoharringtonine, silvestrol, ouabain, tylophorine, and 7‐methoxycryptopleurine) and could be leads for further drug development on their own or as a template for drug design. In addition, a good number of natural products with anti‐corona virus activity are the major constituents of some common dietary supplements, which can be exploited to improve the immunity of the general population in certain epidemics.
•Enhancement of PTC performance by using nanofluids.•High operating temperatures are more suitable for using nanofluids in PTCs.•Exergy efficiency of CuO based nanofluid and is about 9.05%.•1.46% ...more thermal energy can be generated by using 5% of Al2O3 in the base fluid.
Thermal performance of parabolic trough collectors (PTCs) can be improved by suspending nanoparticles into the traditionally used heat transfer fluids. In this work, a one-dimensional mathematical model is proposed to investigate the effect of various nanoprticles suspended in the working fluid for medium and high temperature PTCs. The major finding of this work is that the nanofluid enhances the thermal efficiency of the PTC slightly. High operating temperatures are more suitable for using nanofluids and generate higher relative gains of energy delivered. It is also found that the exergetic efficiency improvement is more important than energetic efficiency. The peak exergy efficiency is achieved by the CuO based nanofluid and is about 9.05%. The maximum daily relative gain of thermal energy delivered is found to be 1.46% by using 5% of Al2O3 in the base fluid. Optimal control of the operating conditions can lead to maximum energetic and exergetic performances of the PTC.
•In this study, experimental investigations were performed to quantify the effect of different configurations of inlet restrictors on the heat transfer performance and pressure drop in a flow boiling ...microchannel heat sink.•Multiple IRs performs best in CHF enhancement at low mass flux, and the 1IR case performs best at high mass flux.•For lower mass flow rates, cases with multiple-opening inlet restrictors generally work better (e.g., higher CHF) than cases with the single-opening inlet restrictor.•The optimum configuration was obtained by maximizing the heat transfer performance (e.g., in terms of CHF enhancement) and minimizing the pressure drop penalties.
Flow boiling instabilities inherent in microchannels / microgaps remain to be a serious issue in two-phase high-heat-flux cooling applications, as they cause significant oscillations in flow rate, temperature, pressure, reduction in heat transfer coefficient (HTC), and eventually early occurrence of critical heat flux (CHF). This study experimentally investigated the effects of various configurations of inlet restrictors (IRs) on the thermal hydraulic performance of flow boiling in a microchannel heat sink, which has a single rectangular microchannel with an aspect ratio of 13.12 and a hydraulic diameter of the 708 µm. The experiments were carried out for the microchannel with three designs of inlet restrictors: one-slot opening (1IR), three-slot openings (3IR), and five-slot openings (5IR), for mass fluxes of 32.68, 81.29 and 144 kg/m2 s, respectively. The effects of the various IRs on the CHF, average HTC and pressure drops of the microchannel heat sink were analyzed. The results showed that all test cases with IRs improved the CHF performance of the flow boiling microchannel heat sink, where the 5IR case works best at low mass flux and the 1IR case works best at high mass flux. The results also illustrated that the IRs reduce the HTC at low mass flux, but improve the HTC at high mass flux and heat flux. IRs always exhibit higher pressure drop penalties. This study also revealed the optimum design for microchannel with IRs, which depends on the operational parameters (e.g., mass flux and heat flux) of the microchannel heat sink.
Nanotechnology is reshaping health care strategies and is expected to exert a tremendous impact in the coming years offering better healthcare facilities. It has led to not only therapeutic drug ...delivery feasibility but also to diagnostics. Materials in the size of nano range (1–100 nm) used in the design, fabrication, regulation, and application of therapeutic drugs or devices are classified as medical nanotechnology and nanopharmacology. Delivery of more complex molecules to the specific site of action as well as gene therapy has pushed forward the nanoparticle-based drug delivery to its maximum. Areas that benefit from nano-based drug delivery systems are cancer, diabetes, infectious diseases, neurodegenerative diseases, blood disorders and orthopedic-related ailments. Moreover, development of nanotherapeutics with multi-functionalities has a considerable potential to fill the gaps that exist in the present therapeutic domain. In cancer treatment, nanomedicines have superiority over current therapeutic practices as they can effectively deliver the drug to the affected tissues, thus reducing drug toxicities. Along this line, polymeric conjugates of asparaginase and polymeric micelles of paclitaxel have recently been recommended for the treatment of various types of cancers. Nanotechnology-based therapeutics and diagnostics provide greater effectiveness with less or no toxicity concerns. Similarly, diagnostic imaging holds promising future applications with newer nano-level imaging elements. Advancements in nanotechnology have emerged to a newer direction which use nanorobotics for various applications in healthcare. Accordingly, this review comprehensively highlights the potentialities of various nanocarriers and nanomedicines for multifaceted applications in diagnostics and drug delivery, especially the potentialities of polymeric nanoparticle, nanoemulsion, solid-lipid nanoparticle, nanostructured lipid carrier, self-micellizing anticancer lipids, dendrimer, nanocapsule and nanosponge-based therapeutic approaches in the field of cancer. Furthermore, this article summarizes the most recent literature pertaining to the use of nano-technology in the field of medicine, particularly in treating cancer patients.
•CFD modeling of thermal stratification inside solar storage tank.•Thermal stratification enhancement via flat plate’s integration through numerical studies.•Investigation of the impact of flat ...plate’s positions and inclinations on thermal stratification.•Quantification of thermal stratification with a set of numerical results.
This study aims to assess the thermal stratification inside a standard hot water storage tank such an important device of solar water heaters. A number of flat plates with different titled positions are integrated inside a vertical tank prototype. The purpose of this investigation is to numerically study the impact of the flat plate positions within a vertical storage tank, which operates during the charging mode, on the thermal stratification and to conduct the possible performance enhancements to achieve. CFD numerical comparison between two configurations was carried out and performance parameters such as temperature evolution, Richardson number and stratification number were calculated. It was shown that thermal stratification inside the storage tank is depending on the flat plate’s positions. Thus, increasing flat plates in different positions inside the storage tank does not establish a suitable thermal stratification. Therefore, a superior thermal performance was achieved for the flat plate which is maintained at the middle height of the storage tank. Also, it was found that flat plate’s integration at different angles improves the thermocline structure development.
Soil salinity is among the leading environmental stresses affecting global agriculture, causing billions of dollars in crop damages every year. Regardless of the cause, ion toxicity, water deficit, ...or nutritional imbalance, high salinity in the root zone severely impedes normal plant growth and development, resulting in reduced crop productivity or crop failure. Development of salt-tolerant cultivars is an attractive and economical approach to solving this problem. Although several salt-tolerant plant genotypes have been developed through transgenic approaches, often they have failed or exhibited limited success under field saline conditions. This is due to several reasons, including the fact that plant growth and development under saline conditions in the field is often influenced by cumulative effects of multiple environmental stresses and genetic factors, which may not have been considered during the development of salt-tolerant transgenic plants. Adoption of inappropriate screening techniques or selection criteria may also lead to selection of genotypes that may not be stress tolerant in a real sense. In most plant species, salt tolerance is a genetically complex trait, often modulated by multiple biosynthetic and signaling pathways. Cross-talks among various stress-controlling pathways have been observed under salt stress, many of which are regulated by transcription factors. Thus, a comprehensive knowledge of the up- and downregulating genes under salt-stress is necessary, which would provide a better understanding of the interactions among pathways in response to salt stress. Attaining such knowledge is a good step toward successful development of salt-tolerant crop cultivars. To this end, DNA microarray technology has been employed to study expression profiles in different plant species and at varying developmental stages in response to salt stress. As a result, large-scale gene expression profiles under salt stress are now available for many plant species, including Arabidopsis, rice, barley, and ice plant. Examinations of such gene expression profiles will help understand the complex regulatory pathways affecting plant salt tolerance and potentially functional characterization of unknown genes, which may be good candidates for developing plants with field salt tolerance. In this article, we review and discuss the current knowledge of plant salt tolerance and the extent to which expression profiling has helped, or will help, a better understanding of the genetic basis of plant salt tolerance. We also discuss possible approaches to improving plant salt tolerance using various tools of biotechnology.
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