28 research outputs found

    Nepal Himalaya Offers Considerable Potential for Pumped Storage Hydropower

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    There is a pressing need for a transition from fossil-fuel to renewable energy to meet the increasing energy demands and reduce greenhouse gas emissions. The Nepal Himalaya possesses substantial renewable energy potential that can be harnessed through hydropower projects due to its peculiar topographic characteristics and abundant water resources. However, the current exploitation rate is low owing to the predominance of run-of-river hydropower systems to support the nation's power system. The utility-scale storage facility is crucial in the load scenario of an integrated Nepalese power system to manage diurnal variation, peak demand, and penetration of intermittent energy sources. In this study, we first identify the potential of pumped storage hydropower across the country under multiple configurations by pairing lakes, hydropower projects, rivers, and available flat terrains. We then identify technically feasible pairs from those of potential locations. Infrastructural, environmental, operational, and other technical constraints govern the choice of feasible locations. We find the flat land-to-river configuration most promising over other configurations for Nepal. Our results provide insight into the potential of pumped storage hydropower and are of practical importance in planning sustainable power systems in the Himalayas

    Drug Susceptibility in Leishmania Isolates Following Miltefosine Treatment in Cases of Visceral Leishmaniasis and Post Kala-Azar Dermal Leishmaniasis

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    Resistance to antimonials has emerged as a major hurdle to the treatment and control of VL and led to the introduction of Miltefosine as first line treatment in the Indian subcontinent. MIL is an oral drug with a long half-life, and it is feared that resistance may emerge rapidly, threatening control efforts under the VL elimination program. There is an urgent need for monitoring treatment efficacy and emergence of drug resistance in the field. In a set of VL/PKDL cases recruited for MIL treatment, we observed comparable drug susceptibility in pre- and post-treatment isolates from cured VL patients while MIL susceptibility was significantly reduced in isolates from VL relapse and PKDL cases. The PKDL isolates showed higher tolerance to MIL as compared to VL isolates. Both VL and PKDL isolates were uniformly susceptible to PMM. MIL transporter genes LdMT/LdRos3 were previously reported as potential resistance markers in strains in which MIL resistance was experimentally induced. The point mutations and the down-regulated expression of these transporters observed in vitro could, however, not be verified in natural populations of parasites. LdMT/LdRos3 genes therefore, do not appear to be suitable markers so far for monitoring drug susceptibility in clinical leishmanial isolates

    Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

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    Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic

    Electrochemical sensing for the detection of 2,4-dichlorophenoxy acetic acid using molecularly imprinted polymer membrane

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    Molecularly imprinted polymer (MIP) membranes were used to develop highly sensitive chemical sensors for the detection of herbicide 2,4-dichlorophenoxy acetic acid (2,4-D). The 2,4-D imprinted composite MIP membranes were prepared, and the characterization was done by UV-VIS spectrophotometer, Fourier transform infrared spectroscopy, and scanning electron microscopy, and the same were fitted in a new electrochemical sensor model. Membrane electroconductivity measurements were performed by applying a small-amplitude alternating voltage (20 mV) with a varying frequency from 20 Hz to 80 kHz generated by a lowfrequency wave form generator. The measured changes in the membrane ionic/electric conductivity as a function of 2,4-D concentration was allowed to evaluate the recognition properties of the prepared membrane. This sensor is useful in detecting 2,4-D herbicide having concentration range 10-3M to 10-6M. The cross-selectivity of the sensor, reproducibility of results, and reusability of MIP membrane were examined and found remarkable and recommendable

    AlN-SWCNT Metacomposites Having Tunable Negative Permittivity in Radio and Microwave Frequencies

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    Discovery of plasmon resonance and negative permittivity in carbon allotropes at much lower frequencies than those of metals has evoked interest to develop random metacomposites by suitable means of addition of these dispersoids in an overall dielectric matrix. Random metacomposites have always the advantage for their easy preparation techniques over those of their regular arrayed artificial counterpart. However, thermal management during the heat generation by electromagnetic attenuation in metamaterials is not yet studied well. The present communication discusses the dielectric permittivities and loss parameters of aluminum nitride-single-wall carbon nanotube (AlN-SWCNT) composites considering high thermal conductivities of both materials. The composites are dense and have been prepared by a standard powder technological method using hot pressing at 1850 degrees C under a nitrogen atmosphere. Increase in the negative permittivity value with SWCNT concentration (1, 3, and 6 vol %) in the composites had been observed at low frequencies. Characterization of the materials with Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and microstructure analysis by scanning and transmission electron microscopy (TEM) revealed the survivability of the SWCNTs and the nature of the matrix-filler interface. Plasmonic resonance following Drude's law could be observed at much lower plasma frequencies than that of pure SWCNT and for very little SWCNT addition. Exhibition of the negative permittivity has been explained with relation to the microstructure of the composites observed from field emission scanning electron micrographs (FESEM), TEM images, and the equivalent circuit model. High energy conversion efficiency is expected in these composites due to the possession of dual functionalities like high thermal conductivity as well as high negative permittivity, which should ensure the application of these materials in wave filter, cloaking device, supercapacitors, and wireless communication

    <i>In vitro</i> miltefosine susceptibility of parasite isolates from VL and PKDL cases before and after Mil treatment.

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    <p>Sensitivity of VL and PKDL isolates at intracellular amastigote stage were determined by infection in murine macrophage cell line J774A.1. Each individual value represents mean IC<sub>50</sub>±SD of the results from two separate assays.</p

    Drug susceptibility of <i>Leishmania donovani</i> clinical isolates following Miltefosine treatment in cases of Visceral Leishmaniasis and Post kala-azar dermal Leishmaniasis.

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    1<p>WHO code: country and year of isolation and the respective strain code, the number following the isolate ID indicates the number of months elapsed after start of MIL treatment.</p>2<p>Research code: Parasites cultured from VL patients were labeled V- and from PKDL patients P-, respectively. The number following the isolate ID indicates the number of months elapsed after start of MIL treatment (e.g. V902/1 means one month passed from first MIL treatment). Parasites isolated from patients' prior start of MIL treatment were labeled as XXX/0 and one month following first treatment was labeled XXX/1. These patients cleared from VL symptoms after respective duration of MIL treatment and were interpreted as clinical cure, although residual parasites could be cultured from splenic aspirates (marked XXX/1). In the period of 1 year follow up, cases of relapse were observed in three VL patients that had shown an initial clinical cure, the isolates obtained were designated as XXX/month in which relapse occurred.</p><p>Cure*- Patients treated with SAG (1000 mg intra muscularly), daily for four months.</p

    One-year clinical outcomes of BioMatrix™-Biolimus A9™ eluting stent: The e-BioMatrix multicenter post marketing surveillance registry in India

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    Objective: The e-BioMatrix is a post marketing multicenter registry with an objective to evaluate the 2 year clinical safety and efficacy outcomes in patients treated with BioMatrix™ - Biolimus A9™ (BA9™) drug eluting stents (DES). Background: Drug-eluting stents still have late-stage disadvantages that might be attributable to the permanent polymer. BioMatrix a new generation DES containing anti-proliferative drug Biolimus A9™ incorporating a biodegradable abluminal coating that leaves a polymer-free stent after drug release enhancing strut coverage while preventing neointimal hyperplasia. Methods: This interim analysis consists of a total of 1189 patients with 1418 lesions treated with BioMatrix stent who entered this multicenter registry in India. We analyzed the incidence of major adverse cardiac events (MACE) and stent thrombosis (ST) at 1, 6, and 12 months with an extended follow-up of 2 years. Recommended antiplatelet regimen included clopidogrel and aspirin for 12 months. Results: The mean age was 57.6 ± 10.9 years, 81.8% were males, comorbidity index was 1.20 ± 1.33, 68% presented with acute coronary syndrome, 49% had hypertension and 40.8% had diabetes mellitus. One-year clinical follow-up was completed in 987 patients at the time of interim analysis. The incidence of MACE is 0.45 for 1544 person-year follow-up. There were only 03 cases of ST (01 late ST) reported during this time. Conclusion: This registry demonstrates excellent one-year clinical safety and efficacy of BioMatrix stents. The 1-year result shows that BioMatrix stent may be a suitable alternative as compared to contemporary DESs which are currently available in the market for simple as well complex disease
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