100 research outputs found

    Nanocrystalline Porous Silicon

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    Graphene-Based Junction Devices for Hydrogen Sensors

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    Graphene is quite a robust material for sensing hydrogen and other gases at room temperature as well as at elevated temperatures with high efficiency. This chapter deals with different junction devices based on graphene for hydrogen sensing. Graphene has excellent electronic attributes that make it suitable for gas sensor devices. However, till date, the research on graphene-based junction devices is not many. In this chapter, we present different types of graphene junction devices suitable for hydrogen sensing. Hydrogen sensor response of these junctions is analyzed, and the sensing mechanism is presented. The temperature- and atmosphere-dependent inversion of n-type to p-type conductivity in graphene is highlighted for hydrogen sensing. Moreover, the two dimensional nature of graphene makes it very convenient for device miniaturization. This chapter provides relevant information on the growth of graphene, the fabrication of different graphene junction devices, and hydrogen sensor applications. Also, the sensor-related concerns such as cross-sensitivity, signal drift, stability, and interference of humidity during hydrogen sensing are thoroughly discussed in this chapter

    A Review on Metal Oxide-Graphene Derivative Nano-Composite Thin Film Gas Sensors

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    Most of the available commercial solid-state gas/vapor sensors are based on metal oxide semiconductors. Metal oxides (MOs) change their conductivity while exposed to gas or vapors ambient can be utilized as gas or vapor sensing materials. In recent days, graphene has attracted tremendous attention owing to its two-dimensional structure with an extremely high surface to volume ratio, electron mobility, and thermal conductivity. However, intrinsic graphene is relatively inefficient for the adsorption of gas/vapor molecules. In this regard, graphene oxide (GO) and reduced graphene oxide (rGO), which are graphene species functionalized with different oxygen groups that offer a higher amount of adsorption sites improving the sensitivity of the film. Up to now, many research groups across the globe have reported the promising performance towards gas detection using various GO/rGO-metal oxide nanocomposites. This chapter reviews the composites of graphene oxide or reduced graphene oxide and metal oxides in nanoscale dimensions (0-D, 1-D, 2-D, and 3-D) for gas sensing applications considering two specific focus areas, that is, synthesis of nanocomposites and performance assessment for gas/vapor sensing

    Double Deadbeat plus Repetitive Control Scheme for Microgrid System

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    Parallel connection of converters is a convenient choice when system capacity is to be increased. Parallel-connected voltage source converters, especially neutral point clamped converters, are one of the best choices for its range. However, with the parallel connectivity, the converter possesses a circulating current in its legs, which consequently threatens the safe operation of the system. To alleviate this circulating current problem, in this paper, a double deadbeat (DD) plus repetitive control (RC) scheme is proposed. The RC scheme is employed to mitigate the circulating currents and the DD loop control scheme is employed to achieve a high operating bandwidth for voltage and current characteristics. Furthermore, the DD loop is associated with an adaptive controlling technique, which adjusts internally by itself and provides better performance for nonlinear loads. The proposed DD method forces the equivalent system elements to be placed outside the closed loop, which does not affect the system stability. Initially, the system has been executed with a conventional proportional + integral scheme and then with the proposed DD + RC scheme. The proposed method is verified by implementing a Simulink model in the OPAL-RT platform. Furthermore, the proposed method is built with a prototype, and its results are explored

    Socioeconomic inequalities in non-communicable diseases prevalence in India: disparities between self-reported diagnoses and standardized measures.

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    BACKGROUND: Whether non-communicable diseases (NCDs) are diseases of poverty or affluence in low-and-middle income countries has been vigorously debated. Most analyses of NCDs have used self-reported data, which is biased by differential access to healthcare services between groups of different socioeconomic status (SES). We sought to compare self-reported diagnoses versus standardised measures of NCD prevalence across SES groups in India. METHODS: We calculated age-adjusted prevalence rates of common NCDs from the Study on Global Ageing and Adult Health, a nationally representative cross-sectional survey. We compared self-reported diagnoses to standardized measures of disease for five NCDs. We calculated wealth-related and education-related disparities in NCD prevalence by calculating concentration index (C), which ranges from -1 to +1 (concentration of disease among lower and higher SES groups, respectively). FINDINGS: NCD prevalence was higher (range 5.2 to 19.1%) for standardised measures than self-reported diagnoses (range 3.1 to 9.4%). Several NCDs were particularly concentrated among higher SES groups according to self-reported diagnoses (Csrd) but were concentrated either among lower SES groups or showed no strong socioeconomic gradient using standardized measures (Csm): age-standardised wealth-related C: angina Csrd 0.02 vs. Csm -0.17; asthma and lung diseases Csrd -0.05 vs. Csm -0.04 (age-standardised education-related Csrd 0.04 vs. Csm -0.05); vision problems Csrd 0.07 vs. Csm -0.05; depression Csrd 0.07 vs. Csm -0.13. Indicating similar trends of standardized measures detecting more cases among low SES, concentration of hypertension declined among higher SES (Csrd 0.19 vs. Csm 0.03). CONCLUSIONS: The socio-economic patterning of NCD prevalence differs markedly when assessed by standardized criteria versus self-reported diagnoses. NCDs in India are not necessarily diseases of affluence but also of poverty, indicating likely under-diagnosis and under-reporting of diseases among the poor. Standardized measures should be used, wherever feasible, to estimate the true prevalence of NCDs

    Основи охорони праці

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    Навчальний посібник містить курс лекцій, теми рефератів та питання, що виносяться на семінарські заняття з дисципліни «Основи охорони праці» для студентів вищих педагогічних навчальних закладів всіх спеціальностей і напрямів підготовки за освітньо-кваліфікаційним рівнем «бакалавр» і курсів післядипломної освіти

    Do girls have a nutritional disadvantage compared with boys?:statistical models of breastfeeding and food consumption inequalities among Indian siblings

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    BACKGROUND: India is the only nation where girls have greater risks of under-5 mortality than boys. We test whether female disadvantage in breastfeeding and food allocation accounts for gender disparities in mortality. METHODS AND FINDINGS: Secondary, publicly available anonymized and de-identified data were used; no ethics committee review was required. Multivariate regression and Cox models were performed using Round 3 of India's National Family and Health Survey (2005-2006; response rate = 93.5%). Models were disaggregated by birth order and sibling gender, and adjusted for maternal age, education, and fixed effects, urban residence, household deprivation, and other sociodemographics. Mothers' reported practices of WHO/UNICEF recommendations for breastfeeding initiation, exclusivity, and total duration (ages 0-59 months), children's consumption of 24 food items (6-59 months), and child survival (0-59 months) were examined for first- and secondborns (n = 20,395). Girls were breastfed on average for 0.45 months less than boys (95% CI: = 0.15 months to 0.75 months, p = 0.004). There were no gender differences in breastfeeding initiation (OR = 1.04, 95% CI: 0.97 to 1.12) or exclusivity (OR = 1.06, 95% CI: 0.99 to 1.14). Differences in breastfeeding cessation emerged between 12 and 36 months in secondborn females. Compared with boys, girls had lower consumption of fresh milk by 14% (95% CI: 79% to 94%, p = 0.001) and breast milk by 21% (95% CI: 70% to 90%, p<0.000). Each additional month of breastfeeding was associated with a 24% lower risk of mortality (OR = 0.76, 95% CI: 0.73 to 0.79, p<0.000). Girls' shorter breastfeeding duration accounted for an 11% increased probability of dying before age 5, accounting for about 50% of their survival disadvantage compared with other low-income countries. CONCLUSIONS: Indian girls are breastfed for shorter periods than boys and consume less milk. Future research should investigate the role of additional factors driving India's female survival disadvantage

    Avant-propos

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    La chute des régimes communistes et l'instauration de démocraties pluralistes en Europe centrale et orientale, accompagnées de proclamations de rupture radicale avec le passé, ont engendré un bouleversement général des repères qui jusque-là permettaient les identifications individuelles et l'élaboration d'identités collectives dans toutes les sphères sociales. Le rejet obligé du passé a été décliné de différentes manières selon les pays, en fonction des diverses expériences du communisme (et de sa chute) dans chacune des sociétés concernées. Toutefois, si les modalités sont variables et les calendriers spécifiques, ces recompositions sociales et politiques se sont toutes inscrites dans un même cadre mental. La condamnation globale du communisme a favorisé des visions polarisées et simplifiées du passé, fondées sur des catégories binaires et des figures stéréotypées, plus ou moins marquées, de bourreaux et de victimes. Au-delà du consensus affiché dans le rejet et la condamnation du communisme, un examen plus fin du rapport au passé dans ces sociétés dites post-communistes souligne la difficulté d'élaborer un discours commun sur le passé (...)

    A Multi-centre Study to Evaluate the Long-Term Efficacy and Safety of Biosimilar Infliximab (Infimab™) in Ankylosing Spondylitis in Real-world Clinical Settings - A perspective from Eastern India

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    Introduction: Owing to dearth of data on infliximab biosimilars in Indian patients, a pan-India case database-based study with infliximab biosimilar BOW015 (Infimab™) was carried out to capture its efficacy and safety in real world clinical settings in India. Here, we assessed its efficacy and safety in ankylosing spondylitis (AS) among patients in the East India cohort. Materials and methods: Data were collected from multiple centers across the eastern region of India. Patients diagnosed with AS, within the preceding 4-6 months during the preceding one year were included in the study. Patients who were given BOW015 for other indications, prior innovator infliximab or other biologics were excluded from the study. Primary variable was Ankylosing Spondylitis Disease Activity Scale (ASDAS) response defined as change of &gt; 2 in the ASDAS score from the baseline by 4-6 months of follow up. Results: The cohort consisted of 149 patients, predominantly male (69.8%), with mean (±SD) age of 36.75 (±11.11) years and mean (±SD) body weight of 58.26 (±15.4) kgs. Of the treated patients, 91 (61.1%) patients were administered four doses, 10 (6.7%) patients were administered three doses, 37 (24.8%) patients were administered two doses and 11 (7.4%) patients were administered only a single dose of BOW015. In the final analysis set, 81 patients had data at baseline and 4th visit. Among the 81 patients, 74 (91%) patients achieved major improvement, 5 (6%) patients achieved clinically important improvement and 2 (3%) were non-responders at 4th visit. Secondarily, cross categorization of the cohort into disease activity categories by number of infusions administered from baseline to 4th visit and assessment of trends in Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores were also carried out and these too confirmed the efficacy of BOW015. Conclusion: Infimab™ (BOW015) showed significant improvement in ASDAS and BASDAI in patients with AS at the end of 4-6 months of follow up with its clinical benefits being apparent as early as first dose of BOW015

    GMRT 333 MHz observations of 6 nearby normal galaxies

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    We report Giant Meterwave Radio Telescope (GMRT) continuum observations of six nearby normal galaxies at 333 MHz. The galaxies are observed with angular resolutions better than ~20" (corresponding to a linear scale of about 0.4 - 1 kpc). These observations are sensitive to all the angular scales of interest, since the resolution of the shortest baseline in GMRT is greater than the angular size of the galaxies. Further, for five of these galaxies we show that at 333 MHz, the mean thermal fraction is less than 5%. Using archival data at about 1 GHz, we estimate the mean thermal fraction to be about 10% at that frequency. We also find that the nonthermal spectral index is generally steeper in regions with low thermal fraction and/or located in the outer parts of the galaxy. In regions of high thermal fraction, the nonthermal spectral index is flatter, and has a narrow distribution peaking at ~ -0.78 with a spread of 0.16, putting stringent constraints on the physical conditions for generation, diffusion and energy losses of cosmic ray electrons at scales of ~ 1 kpc.Comment: 18 pages, 11 figures, Accepted for publication in MNRA
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