In the present study, Ca3Co4O9/ZrO2 composites of various compositions have been synthesized by dispersing the ZrO2 particles in the Ca3Co4O9 matrix and their thermoelectric properties are ...investigated as a function of temperature from room temperature to 553K. For the prepared composite samples, phase purity and microstructure are analyzed. X-ray diffraction studies show that no unwanted reaction has occurred between Ca3Co4O9 and ZrO2 particles during the final sintering process. From scanning electron micrographs, it is observed that all samples show randomly oriented plate-like grains. Furthermore, the electrical resistivity measurement showed that all composite samples exhibit lower electrical resistivity than the pure Ca3Co4O9. The maximum Seebeck coefficient of 177.35μV/K at 553K is achieved for the ZrO2 dispersed Ca3Co4O9 sample. A significant improvement of the power factor (S2σ) has been realized in the prepared composite sample containing 8wt% ZrO2 which is approximately 40% higher than the pure Ca3Co4O9 at 553K. The improved power factor achieved for Ca3Co4O9-8wt% ZrO2 composite sample is mainly due to the obvious decrease in electrical resistivity.
Nowadays AC-DC converter is mostly used for finding dc links in various applications. In any dc system, the prime concern is voltage/current ripples, it could truly affect the system execution on ...both the input and output sides. In this research a single-phase IGBTs (Insulated Gate Bipolar Transistors) based PWM (Pulse width modulated) boost rectifier is simulated. This rectifier circuit is simulated by using IGBT because it is having a high switching speed. It can boost DC output voltage and unity power factor at sinusoidal input with small THD (Total Harmonic Distortion). Generally, the PWM rectifier suffers from pulsating ripple power at double the supply frequency. This unwanted power can be filtered out by selecting a large value of capacitor or an LC branch. To compensate for ripple energy in this system a Proportional Integral controller (PI controller) is proposed. PI controller is used to reducing the output voltage fluctuation and total harmonic distortion of input current. PSIM software is used to design this simulation. Simulation results validate that the projected scheme is effective to minimize the input current harmonic distortion significantly.
Introduction: Electronic health (e-health) initiatives grant the tools and knowledge to improve health care, benefiting not only patients but also healthcare professionals and institutions. ...Objectives: To empower ASHA (Accredited Social Health Activist) technically in terms of using e-health initiatives and to assess feasibility and usefulness of such initiatives; to enhance digital health literacy and to observe the effect of training and skill development of grass root level healthcare workers engaged in primary care. Method: A prospective observational cohort study, in which ASHA’s were recruited in two selected villages of Rajasthan. They were trained to use a web-based application, developed for use on portable device (tablet) to screen, diagnose and provide health education on non-communicable diseases. In-depth interviews and group discussions were done with ASHAs to know their views about the tablet and application use. Results: There was 19.3%, 29.3% and 40% improvement in ASHAs’ ability to measure haemoglobin, blood sugar and blood pressure respectively and also an improvement of 86.5% in tablet and application operation was observed. This improvement in ability of ASHAs was highly significant for all above four parameters (p-value <0.001). ASHAs agreed that the app was useful and helped them connect to the people and explain things more properly. They reported the beneficiaries understood more clearly through pop- up videos which also proved beneficial in increasing compliance. Conclusion: Training ASHA worker in e-health technology is feasible and can assist in screening and management of non-communicable diseases.
Most data on telestroke utilization come from single academic hub-and-spoke telestroke networks. Our objective was to describe characteristics of telestroke consultations among a national sample of ...telestroke sites on one of the most commonly used common vendor platforms, prior to the COVID-19 public health emergency.
A commercial telestroke vendor provided data on all telestroke consultations by two specialist provider groups from 2013-2019. Kendall's τ β nonparametric test was utilized to assess time trends. Generalized linear models were used to assess the association between hospital consult utilization and alteplase use adjusting for hospital characteristics.
Among 67,736 telestroke consultations to 132 spoke sites over the study period, most occurred in the emergency department (90%) and for stroke indications (final clinical diagnoses: TIA 13%, ischemic stroke 39%, hemorrhagic stroke 2%, stroke mimics 46%). Stroke severity was low (median NIHSS 2, IQR 0–6). Alteplase was recommended for 23% of ischemic stroke patients. From 2013 to 2019, times from ED arrival to NIHSS, CT scan, imaging review, consult, and alteplase administration all decreased (p<0.05 for all), while times from consult start to alteplase recommendation and bolus increased (p<0.01 for both). Transfer was recommended for 8% of ischemic stroke patients. Number of patients treated with alteplase per hospital increased with increasing number of consults and hospital size and was also associated with US region in unadjusted and adjusted analyses. Longer duration of hospital participation in the network was associated with shorter hospital median door-to-needle time for alteplase delivery (39 min shorter per year, p=0.04).
Among spoke sites using a commercial telestroke platform over a seven-year time horizon, times to consult start and alteplase bolus decreased over time. Similar to academic networks, duration of telestroke participation in this commercial network was associated with faster alteplase delivery, suggesting practice improves performance.
INTRODUCTIONPreviously laid down criteria for lesional stability of vitiligo are inconsistent. Longitudinal data on correlation between dermoscopic features of vitiligo and disease activity is ...limited.OBJECTIVESTo sequentially determine the dermoscopic features of vitiligo and to assess their association with the dynamic nature of the vitiligo patch.METHODSSixty patients with 200 vitiligo patches fulfilling the inclusion criteria on medical therapy were subjected to sequential clinical and dermoscopic examination for 6 months. Baseline lesional photographs, dermoscopy and tracing of the patch was made and repeated at 6 months. The follow up tracing was superimposed onto the baseline tracing. Based on the increase or decrease in size, their outcomes were grouped as responsive, progressive and quiescent. Paired analysis of dermoscopic features was done between baseline, and their follow up after 6 months.RESULTSWell defined border was associated with static nature of the vitiligo patch and ill-defined borders and trichrome pattern depicted its dynamic nature. Statistically significant increase in leukotrichia and satellite lesions amongst progressive patches and a decrease amongst responsive patches was observed. Pigment network changes were statistically significant for both responsive and progressive patches. Satellite lesions and micro-Koebner's phenomena was suggestive of progressive disease, while perifollicular pigmentation and perilesional hyperpigmentation was suggestive of re-pigmenting disease and proved to be an early marker for response to therapy.CONCLUSIONSRepeated dermoscopic evaluation of lesions in a serial manner to assess disease activity helps understand their evolving nature and is a valuable tool in planning appropriate further treatment.
Introduction: Electronic health (e-health) initiatives grant the tools and knowledge to improve health care, beneiting not only patients but also healthcare professionals and institutions. ...Objectives: To empower ASHA (Accredited Social Health Activist) technically in terms of using e-health initiatives and to assess feasibility and usefulness of such initiatives; to enhance digital health literacy and to observe the effect of training and skill development of grass root level healthcare workers engaged in primary care. Method: A prospective observational cohort study, in which ASHA's were recruited in two selected villages of Rajasthan. They were trained to use a web-based application, developed for use on portable device (tablet) to screen, diagnose and provide health education on non-communicable diseases. In-depth interviews and group discussions were done with ASHAs to know their views about the tablet and application use. Results: There was 19.3%, 29.3% and 40% improvement in ASHAs' ability to measure haemoglobin, blood sugar and blood pressure, respectively and also an improvement of 86.5% in tablet and application operation was observed. This improvement in ability of ASHAs was highly signiicant for all above four parameters(p-value <0.001).ASHAs agreed that the app was useful and helped them connect to the people and explain things more properly. They reported the beneiciaries understood more clearly through pop- up videos which also proved beneicial in increasing compliance. Conclusion: Training ASHA worker in e-health technology is feasible and can assist in screening and management of non-communicable diseases.
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