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Abstract Smart, low-cost and portable gas sensors are highly desired due to the importance of air quality monitoring for environmental and defense-related applications. Traditionally, electrochemical and nondispersive infrared (IR) gas sensors are designed to detect a single specific analyte. Although IR spectroscopy-based sensors provide superior performance, their deployment is limited due to their large size and high cost. In this study, a smart, low-cost, multigas sensing system is demonstrated consisting of a mid-infrared microspectrometer and a machine learning algorithm. The microspectrometer is a metasurface filter array integrated with a commercial IR camera that is consumable-free, compact ( ~ 1 cm3) and lightweight ( ~ 1 g). The machine learning algorithm is trained to analyze the data from the microspectrometer and predict the gases present. The system detects the greenhouse gases carbon dioxide and methane at concentrations ranging from 10 to 100% with 100% accuracy. It also detects hazardous gases at low concentrations with an accuracy of 98.4%. Ammonia can be detected at a concentration of 100 ppm. Additionally, methyl-ethyl-ketone can be detected at its permissible exposure limit (200 ppm); this concentration is considered low and nonhazardous. This study demonstrates the viability of using machine learning with IR spectroscopy to provide a smart and low-cost multigas sensing platform.

The alkaline oxygen evolution reaction (OER) remains a bottleneck in green hydrogen production owing to its slow reaction kinetics and low catalytic efficiencies of earth abundant electrocatalysts in the alkaline OER reaction. This study investigates the OER performance of hierarchically porous cobalt electrocatalysts synthesized using the dynamic hydrogen bubble templating (DHBT) method. Characterization studies revealed that electrocatalysts synthesized under optimized conditions using the DHBT method consisted of cobalt nanosheets, and hierarchical porosity with macropores distributed in a honeycomb network and mesopores distributed between cobalt nanosheets. Moreover, X-ray photoelectron spectroscopy studies revealed the presence of Co(OH)2 as the predominant surface cobalt species while Raman studies revealed the presence of the cubic Co3O4 phase in the synthesized electrocatalysts. The best performing electrocatalyst required only 360 mV of overpotential to initiate a current density of 10 mA cm−2, exhibited a Tafel slope of 37 mV dec−1, and stable OER activity over 24 h. The DHBT method offers a facile, low cost and rapid synthesis approach for preparation for highly efficient cobalt electrocatalysts.

BackgroundAsian Indians are at higher risk of cardiometabolic disease compared to other ethnic groups, and the age of onset is typically younger. Cardiac structure and function are poorly characterized in this ethnic group. In this study, we describe image-acquisition methods and the reproducibility of measurements and detailed echocardiography characteristics in two large Indian population-based cohorts (the New Delhi and Vellore Birth Cohorts) from India.MethodsThe IndEcho study captured transthoracic echocardiographic measurements of cardiac structure and function from 2,322 men and women aged 43–50 years. M-mode measurements in the parasternal long axis (PLAX) and 2-dimensional (2D) short axis recordings at the mitral valve, mid-papillary and apical level were recorded. Apical 2D recordings of two- three- and four-chamber (2C, 3C and 4C) views and Doppler images (colour, pulsed and continuous) were recorded in cine-loop format. Left ventricular (LV) mass, LV hypertrophy, and indices of LV systolic and diastolic function were derived.ResultsEchocardiographic measurements showed good/excellent technical reproducibility. Hetero-geneity across sites, sex and rural/urban differences in cardiac structure and function were observed. Overall, this cohort of South Asian Indians had smaller LV mass and normal systolic and diastolic function when compared with published data on other Asian Indians and the West, (LV mass indexed for body surface area: Delhi men: 68 g/m2, women 63.9; Vellore men: 65.8, women 61.6) but were within ethnic-specific reference ranges. The higher prevalence of obesity, diabetes and hypertension is reflected by the higher proportion of LV remodelling and lesser hypertrophy.ConclusionsOur study adds to scarce population-based echocardiographic data for mid-life Asian Indians. Compared to published literature on other ethnic groups, the Asian Indian heart is characterised by smaller cardiac dimensions and normal range systolic and diastolic function on a background of a high prevalence of hypertension, diabetes and cardiac disease at a relatively young age. This data will form the basis for further analyses of lifecourse, metabolic and body composition predictors of cardiac structure and function, and echocardiographic predictors of future mortality.ISRCTN registration number13432279

Background: Adherence to National Airborne Infection Control Guidelines (NAIC) by health-care facilities is an effective way of reducing the spread of air-borne infections such as H1N1, drug-resistant tuberculosis, and COVID-19 disease. Aims and Objectives: This study aims to assess the gaps in knowledge, attitude, implementation, and satisfaction regarding resources availability of NAIC among postgraduate resident doctors. Materials and Methods: Across-sectional study was conducted from December 2019 to February 2021 at a medical college in central India. Total 301 interns, postgraduates, and senior residents in surgery and medicine allied clinical departments were included by convenient sampling method. A pre-designed, self-administered questionnaire was used to assess knowledge, attitude, and practice (KAP) and their satisfaction with available resources regarding NAIC. The data collected were tabulated and were analyzed using descriptive test and comparison of means by Analysis of variance test. Results: Almost 95%, 77%, and 74% of study participants were having adequate KAP on NAIC, respectively. Sixty-one percent participants were satisfied with the resources availability in their work area. Statistically significant association was observed between participants age, designation with their KAP score (P

Despite the availability of chromatin conformation capture experiments, discerning the relationship between the 1D genome and 3D conformation remains a challenge. Here, the authors propose a method that produces low-dimensional latent representations that summarize intra-chromosomal Hi-C contacts.

Objective We examined associations among serial measures of linear growth and relative weight with adult body composition.Design Secondary data analysis of prospective birth cohort studies.Settings Six birth cohorts from Brazil, Guatemala, India, the Philippines and South Africa.Participants 4173 individuals followed from birth to ages 22–46 years with complete and valid weight and height at birth, infancy, childhood and adolescence, and body composition in adult life.Exposures Birth weight and conditional size (standardised residuals of height representing linear growth and of relative weight representing weight increments independent of linear size) in infancy, childhood and adolescence.Primary outcome measures Body mass index, fat mass index (FMI), fat-free mass index (FFMI), fat mass/fat-free mass ratio (FM/FFM), and waist circumference in young and mid-adulthood.Results In pooled analyses, a higher birth weight and relative weight gains in infancy, childhood and adolescence were positively associated with all adult outcomes. Relative weight gains in childhood and adolescence were the strongest predictors of adult body composition (β (95% CI) among men: FMI (childhood: 0.41 (0.26 to 0.55); adolescence: 0.39 (0.27 to 0.50)), FFMI (childhood: 0.50 (0.34 to 0.66); adolescence: 0.43 (0.32 to 0.55)), FM/FFM (childhood: 0.31 (0.16 to 0.47); adolescence: 0.31 (0.19 to 0.43))). Among women, similar patterns were observed, but, effect sizes in adolescence were slightly stronger than in childhood. Conditional height in infancy was positively associated with FMI (men: 0.08 (0.03 to 0.14); women: 0.11 (0.07 to 0.16)). Conditional height in childhood was positively but weakly associated with women’s adiposity. Site-specific and sex-stratified analyses showed consistency in the direction of estimates, although there were differences in their magnitude.Conclusions Prenatal and postnatal relative weight gains were positive predictors of larger body size and increased adiposity in adulthood. A faster linear growth in infancy was a significant but weak predictor of higher adult adiposity.

Abstract Transition metal oxide (TMO)‐based anodes attract much attention for lithium storage due to the merits of high theoretical capacity, facile synthesis, and easy scale‐up. Moreover, the increased working potential avoids the issue of lithium dendrites formation and thus improves battery safety. Herein, we propose a route to significantly improve the electrochemical performance of TMO anodes through configurational entropy optimization. For example, high‐entropy oxide (FeCoNiCrCu)3O4 is synthesized by carefully selecting metal elements. The (FeCoNiCrCu)3O4 electrode ensures not only low potential but also holds high capacity. In the half‐cell configuration, the (FeCoNiCrCu)3O4 electrode provides a specific capacity of 575.7 mAh g−1 after 200 cycles at 0.2 A g−1. More importantly, the electrode showed a relatively low discharge voltage of 0.39 V at 0.5 A g−1, which is caused by the configuration entropy optimization. The assembled (FeCoNiCrCu)3O4//LCO coin‐type full cell exhibits a high capacity of 266.3 mAh g−1 after 100 cycles at 0.2 A g−1 and an operating voltage up to 3.9 V.

In this paper we introduce the concept of tension on an edge in a graph. The tension on an edge in a graph is the number of geodesics passing through it. We investigate some results and characterizations involving tensions on edges in graphs.