1,114 research outputs found

    Impact of Cold Start on Vehicle Fuel Economy and Performance

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    The goal of this research is to understand and quantify the impact and effects of low temperature operation has on the performance and efficiency of vehicle fuel cell systems through modeling. More specifically, this work addresses issues of the initial thermal transient known to the automotive community as “cold-start” effects. Cold-start effects play a significant role in power limitations in a fuel cell vehicle, and may require hybridization (batteries) to supplement available power. A fuel cell system model developed as part of this work allows users to define the basic thermal fluid relationships in a fuel cell system. The model can be used as a stand-alone version or as part of a complex fuel cell vehicle model. Fuel cells are being considered for transportation primarily because they have the ability to increase vehicle energy efficiency and significantly reduce or eliminate tailpipe emissions. A proton exchange membrane fuel cell is an electrochemical device for which the operational characteristics depend heavily upon temperature. Thus, it is important to know how the thermal design of the system affects the performance of a fuel cell, which governs the efficiency and performance of the system

    GERIATRIC HEALTH CARE THROUGH NUTRACEUTICALS OF MORINDA CITRIFOLIA L.: A REVIEW

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    Ageing (Jara) is a natural process and an inevitable phenomenon in life. Ageing not only brings about a continued generalized involution of the biosystem, it also predisposes in aged individual to set of diseases and disorder warranting special medical care. Problems of geriatric age group health problems are joint problems, impairment of special senses, cardio vascular disease, hypothermia, cancer, prostate enlargement, diabetes & accidental falls psychological problems. Noni is the common name for Morinda citrifolia L and is also called Indian Mulberry. Morinda species has been described in Ayurveda as the name of Akshiki phala, Ashyuka and also used in folk remedies by traditionally for over 2000 years, and is reported to have a broad range of therapeutic effects, including antibacterial, antiviral, antifungal, antitumor, antihelmin, analgesic, hypotensive, anti-inflammatory, and immune enhancing effects. The aim of this study is to explore the importance of Morinda citrifolia to reveal the nutritional and medicinal value of the Noni plant, and to summarize scientific evidence that supports it geriatric health care through its neutraceuticals such as vit C, flavanoids, tannins and antioxidants

    Comparative study of titanium elastic nailing versus hip spica in treatment of femoral shaft fractures in children

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    Background: There is no consensus on treatment of closed femoral-shaft fractures in children. We compared hip spica cast with titanium elastic nailing (TEN) in the treatment of femoral-shaft fractures in children.Methods: Study was conducted at SMS Medical College, Jaipur (Rajasthan). Out of 90 Patients of diaphyseal fracture femur, 45were treated conservatively by spica cast and 45 were treated with TEN. Follow up done regularly up to twelve months of injury with taking into account, various parameters.Results: All diaphyseal fractures of femur healed, whether treated conservatively by spica cast or treated operatively with TEN. The time of union and weight bearing was less in operative group as comparative to spica cast group. Ten patients (22.22%) in spica group compared to three patients (6.66%) in operative group had malunion and two patients (4.4%) in spica group compared none in operative group had delayed union.Conclusions: Results of TEN turned out to be far superior to traction and spica cast treatment in paediatric femoral fractures. Rate of complications was far low with operative than conservative Treatment

    Evaluating Atypical Gaze Patterns through Vision Models: The Case of Cortical Visual Impairment

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    A wide range of neurological and cognitive disorders exhibit distinct behavioral markers aside from their clinical manifestations. Cortical Visual Impairment (CVI) is a prime example of such conditions, resulting from damage to visual pathways in the brain, and adversely impacting low- and high-level visual function. The characteristics impacted by CVI are primarily described qualitatively, challenging the establishment of an objective, evidence-based measure of CVI severity. To study those characteristics, we propose to create visual saliency maps by adequately prompting deep vision models with attributes of clinical interest. After extracting saliency maps for a curated set of stimuli, we evaluate fixation traces on those from children with CVI through eye tracking technology. Our experiments reveal significant gaze markers that verify clinical knowledge and yield nuanced discriminability when compared to those of age-matched control subjects. Using deep learning to unveil atypical visual saliency is an important step toward establishing an eye-tracking signature for severe neurodevelopmental disorders, like CVI.Comment: 5 pages, 4 figures, submitted to IEEE EMBC 202

    Optical control of resonant light transmission for an atom-cavity system

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    We demonstrate the manipulation of transmitted light through an optical Fabry-Pérot cavity, built around a spectroscopy cell containing enriched rubidium vapor. Light resonant with the 87RbD2 (F=2,F=1) ↔F′ manifold is controlled by the transverse intersection of the cavity mode by another resonant light beam. The cavity transmission can be suppressed or enhanced depending on the coupling of atomic states due to the intersecting beams. The extreme manifestation of the cavity-mode control is the precipitous destruction (negative logic switching) or buildup (positive logic switching) of the transmitted light intensity on intersection of the transverse control beam with the cavity mode. Both the steady-state and transient responses are experimentally investigated. The mechanism behind the change in cavity transmission is discussed in brief

    Generalized analysis on BKρB\to K^* \rho within and beyond the Standard Model - Can it help understand the BKπB \to K \pi puzzle?

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    We study BKρB \to K^* \rho modes that are analogues of the much studied BKπB\to K \pi modes with B decaying to two vector mesons instead of pseudoscalar mesons, using topological amplitudes in the quark diagram approach. We show how BKρB \to K^*\rho modes can be used to obtain many more observables than those for BKπB \to K \pi modes, even though the quark level subprocesses of both modes are exactly the same. All the theoretical parameters (except for the weak phase γ\gamma), such as the magnitudes of the topological amplitudes and their strong phases, can be determined in terms of the observables without any model-dependent assumption. We demonstrate how BKρB\to K^*\rho can also be used to verify if there exist any relations between theoretical parameters, such as the hierarchy relations between the topological amplitudes and possible relations between the strong phases. Conversely, if there exist reliable theoretical estimates of amplitudes and strong phases, the presence of New physics could be probed. We show that if the tree and color-supressed tree are related to the electroweak penguins and color-supressed electroweak penguins, it is not only possible to verify the validity of such relations but also to have a clean measurement of New Physics parameters. We also present a numerical study to examine which of the observables are more sensitive to New Physics.Comment: 25 pages, 2 figure

    Exposure to the Dioxin-like Pollutant PCB 126 Afflicts Coronary Endothelial Cells via Increasing 4-Hydroxy-2 Nonenal: A Role for Aldehyde Dehydrogenase 2

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    Exposure to environmental pollutants, including dioxin-like polychlorinated biphenyls (PCBs), play an important role in vascular inflammation and cardiometabolic diseases (CMDs) by inducing oxidative stress. Earlier, we demonstrated that oxidative stress-mediated lipid peroxidation derived 4-hydroxy-2-nonenal (4HNE) contributes to CMDs by decreasing the angiogenesis of coronary endothelial cells (CECs). By detoxifying 4HNE, aldehyde dehydrogenase 2 (ALDH2), a mitochondrial enzyme, enhances CEC angiogenesis. Therefore, we hypothesize that ALDH2 activation attenuates a PCB 126-mediated 4HNE-induced decrease in CEC angiogenesis. To test our hypothesis, we treated cultured mouse CECs with 4.4 µM PCB 126 and performed spheroid and aortic ring sprouting assays, the ALDH2 activity assay, and Western blotting for the 4HNE adduct levels and real-time qPCR to determine the expression levels of Cyp1b1 and oxidative stress-related genes. PCB 126 increased the gene expression and 4HNE adduct levels, whereas it decreased the ALDH2 activity and angiogenesis significantly in MCECs. However, pretreatment with 2.5 µM disulfiram (DSF), an ALDH2 inhibitor, or 10 µM Alda 1, an ALDH2 activator, before the PCB 126 challenge exacerbated and rescued the PCB 126-mediated decrease in coronary angiogenesis by modulating the 4HNE adduct levels respectively. Finally, we conclude that ALDH2 can be a therapeutic target to alleviate environmental pollutant-induced CMDs

    A study on wire breakage and parametric efficiency of the wire electro chemical discharge machining process 1

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    Abstract: -The Wire Electrochemical Discharge Machining (WECDM) is a nonconventional process, typically used in cutting brittle and hard non-conductive materials. The WECDM is relatively new research area compared to its principle process-'Electro Chemical Discharge Machining (ECDM). In the current investigation, the wire breakage problem, commonly encountered while machining fine slots has been addressed. The aim was to reduce the wire breakage through optimum parametric settings, to understand the wire breaking voltages at different electrolytic concentrations along with its effect on the MRR, length of cut and width of cut. In this study, zinc diffused brass wire of fine diameter (0.20 mm) was used in experiments and the results of the same are being reported in the paper. The response parameters used in the investigation were MRR and width of cut; while the process parameters were workpiece feed rate, electrolyte concentrations and applied voltage

    Inhibitory effect of phytochemicals towards SARS-CoV-2 papain like protease (PLpro) proteolytic and deubiquitinase activity

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    Recent studies have shown that RNA-dependent RNA polymerase (RdRp), 3-chymotrypsin-like protease (3CLpro), and papain-like protease (PLpro) are necessary for SARS-CoV-2 replication. Among these three enzymes, PLpro exhibits both proteolytic and deubiquitinase (DUB) activity and is responsible for disrupting the host\u27s innate immune response against SARS-CoV-2. Because of this unique property of PLpro, we investigated the inhibitory effects of phytochemicals on the SARS-CoV-2 PLpro enzyme. Our data indicates that the phytochemicals such as catechin, epigallocatechin gallate (EGCG), mangiferin, myricetin, rutin, and theaflavin exhibited inhibitory activity with IC50 values of 14.2, 128.4, 95.3, 12.1, and 43.4, and 7.3 μM, respectively, towards PLpro proteolytic activity. However, the IC50 values of quercetin, oleuropein, and γ-mangostin are ambiguous. We observed that EGCG, mangiferin, myricetin, oleuropein, rutin, and theaflavin have also inhibited the DUB activity with IC50 values of 44.7, 104.3, 29.2, 131.5, 61.7, and 13.2 μM, respectively. Mechanistically, the ligand-protein interaction structural modeling suggests that mangiferin, EGCG, theaflavin, and oleuropein shows that these four ligands interact with Glu167, and Tyr268, however mangiferin and oleuropein showed very weak interaction with Glu167 as compared to EGCG, and theaflavin which reflects their low IC50 values for DUB activity. Our data indicate that the phytochemicals mentioned above inhibit the proteolytic and DUB activity of SARS-CoV-2 PLpro, thus preventing viral replication and promoting host innate immune response. However, the therapeutic potential of these phytochemicals needs to be validated by pre-clinical and clinical studies
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