135 research outputs found
The Formation And Decomposition Of Nickel Carbide In Evaporated Nickel Films On Graphite
Auger electron spectroscopy and X-ray photoelectron spectroscopy were used to study nickel carbide (Ni3C) formed during the evaporation of nickel onto the surface of single-crystal graphite. It is shown that Ni3C formed in this manner extends from the surface to close to the interface. A model is proposed to explain the mechanism of Ni3C formation. The 1s photoelectron peak from Ni3C is observed to have a binding energy 0.6 eV lower than that of pure graphite. This is attributed to the lack of any significant ionic bonding in Ni3C. © 1978
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Ethical and human rights considerations related to access to anemia diagnosis
Important disparities exist in anemia diagnosis globally. We examine individualsâ and populationsâ access to anemia diagnosis, the accuracy of diagnostic tests, and the interpretation of test results through the lens of key ethical considerations. These include the human right to health and the Rawlsian concept of the social contract, as well as ethical principles, such as autonomy, selfâliberty, beneficence, and nonmaleficence. We discuss factors that influence individualsâ and communitiesâ access to highâquality health services, including geography, gender, age, and socioeconomic status. Geographic and other differences exist in the types of diagnostic equipment and methods used to diagnose anemia, potentially leading to differential classification of anemia across individuals and populations. A diagnosis of anemia also requires followâup to understand etiology and appropriate treatment. However, this is not done consistently, in clinical care or in populationâbased surveys. To better understand the problem and track countriesâ progress, a need exists for disaggregated, longitudinal quantitative and qualitative data on disparities related to anemia. Moving forward, it will be important for countries to improve equitable access to highâquality health services, particularly primary health care services, and to address barriers to the ability of individuals or communities to effectively enjoy the right to health
Using structural equation modelling to untangle sanitation, water and hygiene pathways for intervention improvements in height-for-age in children <5 years old
AbstractBackgroundDespite a strong theoretical rationale for combining water, sanitation and hygiene (WaSH) interventions to improve child health, study findings are heterogeneous with little understanding of the mechanisms for these effects. Our study objective was to demonstrate the utility of structural equation modeling (SEM) to assess intervention effects on height-for-age z score (HAZ) through the complex system of WaSH pathways.MethodsWe used data from a matched cohort effectiveness evaluation of a combined on-premise piped water and improved sanitation intervention in rural Odisha, India. Height/length was measured in children 0ĂŻÂżÂœ59?months old (n?=?1826) from 90 matched villages in FebruaryĂŻÂżÂœJune 2016. WaSH behaviours and infrastructure were assessed through household surveys and observation, respectively. We used SEM to calculate the standardized path coefficients and the total contributions of WaSH pathways to HAZ.ResultsIntervention improvements on HAZ were through the sanitation pathway (coverage ? use ?: 0.722; use ? HAZ ?: 0.116), with piped water coverage indirectly affecting HAZ through improved sanitation use (?: 0.148). Although the intervention had a positive association with handwashing station coverage, there was no evidence of a total hygiene pathway effect on HAZ or further direct effects through the water pathways.ConclusionsThis study demonstrates the utility of SEM to assess the mechanisms through which combined WaSH interventions impact HAZ as a system of pathways, providing a more nuanced assessment than estimation of the total intervention effect. Our finding, that water impacts HAZ through the sanitation pathway, is an important and actionable insight for WaSH programming.</jats:sec
Warm molecular gas temperature distribution in six local infrared bright Seyfert galaxies
<p><b>A, C, E and G</b>: Summarized data depicting the effect of L-NAME (100 ΌM) or endothelium removal (denuded) on propofol-induced (does-dependent) changes in luminal diameter in coronary microvessels obtained from control, TRPV1<sup>-/-</sup>, TRPA1<sup>-/-</sup> and TRPAV<sup>-/-</sup> mice, respectively (<i>n</i> = 12). <b>B, D, F and H</b>: Summarized data depicting the effect of Pen A (50 ΌM) alone and in combination with L-NAME on propofol-induced changes in luminal diameter in coronary microvessels obtained from control, TRPV1<sup>-/-</sup>, TRPA1<sup>-/-</sup> and TRPAV<sup>-/-</sup> mice, respectively (<i>n</i> = 12). Data are expressed as % relaxation ± SEM. *<i>P</i>< 0.05 vs. control.</p
Effect of community health clubs on child diarrhoea in western Rwanda: cluster-randomised controlled trial
Background Community health clubs are multi-session village-level gatherings led by trained facilitators and designed
to promote healthy behaviours mainly related to water, sanitation, and hygiene. They have been implemented in
several African and Asian countries but have never been evaluated rigorously. We aimed to evaluate the effect of
two versions of the community health club model on child health and nutrition outcomes.
Methods We did a cluster-randomised trial in Rusizi district, western Rwanda. We defined villages as clusters.
We assessed villages for eligibility then randomly selected 150 for the study using a simple random sampling routine
in Stata. We stratified villages by wealth index and by the proportion of children younger than 2 years with caregiverreported
diarrhoea within the past 7 days. We randomly allocated these villages to three study groups: no intervention
(control; n=50), eight community health club sessions (Lite intervention; n=50), or 20 community health club sessions
(Classic intervention; n=50). Households in these villages were enrolled in 2013 for a baseline survey, then re-enrolled
in 2015 for an endline survey. The primary outcome was caregiver-reported diarrhoea within the previous 7 days in
children younger than 5 years. Analysis was by intention to treat and per protocol. This trial is registered with
ClinicalTrials.gov, number NCT01836731.
Findings At the baseline survey undertaken between May, 2013, and August, 2013, 8734 households with children
younger than 5 years of age were enrolled. At the endline survey undertaken between Sept 21, 2015, and
Dec 22, 2015, 7934 (91%) of the households were re-enrolled. Among children younger than 5 years, the prevalence
of caregiver-reported diarrhoea in the previous 7 days was 514 (14%) of 3616 assigned the control, 453 (14%)
of 3196 allocated the Lite intervention (prevalence ratio compared with control 0·97, 95% CI 0·81â1·16; p=0·74),
and 495 (14%) of 3464 assigned the Classic intervention (prevalence ratio compared with control 0·99, 0·85â1·15;
p=0·87).
Interpretation Community health clubs, in this setting in western Rwanda, had no effect on caregiver-reported
diarrhoea among children younger than 5 years. Our results question the value of implementing this intervention at
scale for the aim of achieving health gains
Design and rationale of a matched cohort study to assess the effectiveness of a combined household-level piped water and sanitation intervention in rural Odisha, India.
INTRODUCTION: Government efforts to address massive shortfalls in rural water and sanitation in India have centred on construction of community water sources and toilets for selected households. However, deficiencies with water quality and quantity at the household level and community coverage and actual use of toilets have led Gram Vikas, a local non-governmental organization in Odisha, India, to develop an approach that provides household-level piped water connections contingent on full community-level toilet coverage. METHODS: This matched cohort study was designed to assess the effectiveness of a combined piped water and sanitation intervention. Households with children <5â
years in 45 randomly selected intervention villages and 45 matched control villages will be followed over 17â
months. The primary outcome is prevalence of diarrhoeal diseases; secondary health outcomes include soil-transmitted helminth infection, nutritional status, seroconversion to enteric pathogens, urogenital infections and environmental enteric dysfunction. In addition, intervention effects on sanitation and water coverage, access and use, environmental fecal contamination, women's empowerment, as well as collective efficacy, and intervention cost and cost-effectiveness will be assessed. ETHICS AND DISSEMINATION: The study protocol has been reviewed and approved by the ethics boards of the London School of Hygiene and Tropical Medicine, UK and KIIT University, Bhubaneswar, India. Findings will be disseminated via peer-reviewed literature and presentation to stakeholders, government officials, implementers and researchers. TRIAL REGISTRATION NUMBER: NCT02441699
Child diarrhoea and nutritional status in rural Rwanda: a cross-sectional study to explore contributing environmental and demographic factors.
OBJECTIVE: To explore associations of environmental and demographic factors with diarrhoea and nutritional status among children in Rusizi district, Rwanda. METHODS: We obtained cross-sectional data from 8847 households in May-August 2013 from a baseline survey conducted for an evaluation of an integrated health intervention. We collected data on diarrhoea, water quality, and environmental and demographic factors from households with children <5, and anthropometry from children <2. We conducted log-binomial regression using diarrhoea, stunting and wasting as dependent variables. RESULTS: Among children <5, 8.7% reported diarrhoea in the previous 7Â days. Among children <2, stunting prevalence was 34.9% and wasting prevalence was 2.1%. Drinking water treatment (any method) was inversely associated with caregiver-reported diarrhoea in the previous 7Â days (PRÂ =Â 0.79, 95% CI: 0.68-0.91). Improved source of drinking water (PRÂ =Â 0.80, 95% CI: 0.73-0.87), appropriate treatment of drinking water (PRÂ =Â 0.88, 95% CI: 0.80-0.96), improved sanitation facility (PRÂ =Â 0.90, 95% CI: 0.82-0.97), and complete structure (having walls, floor and roof) of the sanitation facility (PRÂ =Â 0.65, 95% CI: 0.50-0.84) were inversely associated with stunting. None of the exposure variables were associated with wasting. A microbiological indicator of water quality was not associated with diarrhoea or stunting. CONCLUSIONS: Our findings suggest that in Rusizi district, appropriate treatment of drinking water may be an important factor in diarrhoea in children <5, while improved source and appropriate treatment of drinking water as well as improved type and structure of sanitation facility may be important for linear growth in children <2. We did not detect an association with water quality
Assessing longer-term effectiveness of a combined household-level piped water and sanitation intervention on child diarrhoea, acute respiratory infection, soil-transmitted helminth infection and nutritional status: a matched cohort study in rural Odisha, India.
BACKGROUND: Open defecation is widespread in rural India, and few households have piped water connections. While government and other efforts have increased toilet coverage in India, and evaluations found limited immediate impacts on health, longer-term effects have not been rigorously assessed. METHODS: We conducted a matched cohort study to assess the longer-term effectiveness of a combined household-level piped water and sanitation intervention implemented by Gram Vikas (an Indian NGO) in rural Odisha, India. Forty-five intervention villages were randomly selected from a list of those where implementation was previously completed at least 5âyears before, and matched to 45 control villages. We conducted surveys and collected stool samples between June 2015 and October 2016 in households with a child <5 years of age (nâ=â2398). Health surveillance included diarrhoea (primary outcome), acute respiratory infection (ARI), soil-transmitted helminth infection, and anthropometry. RESULTS: Intervention villages had higher improved toilet coverage (85% vs 18%), and increased toilet use by adults (74% vs 13%) and child faeces disposal (35% vs 6%) compared with control villages. There was no intervention association with diarrhoea [adjusted OR (aOR): 0.94, 95% confidence interval (CI): 0.74-1.20] or ARI. Compared with controls, children in intervention villages had lower helminth infection (aOR: 0.44, 95% CI: 0.18, 1.00) and improved height-for-age z scores (HAZ) (+0.17, 95% CI: 0.03-0.31). CONCLUSIONS: This combined intervention, where household water connections were contingent on community-wide household toilet construction, was associated with improved HAZ, and reduced soil-transmitted helminth (STH) infection, though not reduced diarrhoea or ARI. Further research should explore the mechanism through which these heterogenous effects on health may occur
High-Efficiency Multi-Junction Space Solar Development Utilizing Lattice Grading
Progress towards achieving a high one-sun air mass 0 (AM0) efficiency in a monolithic dual junction solar cell comprised of a 1.62 eV InGaP top cell and a 1.1 eV InGaAs bottom cell grown on buffered GaAs is reported. The performance of stand-alone 1.62 eV InGaP and 1.1 eV InGaAs cells is compared to that of the dual junction cell. Projected AM0 efficiencies of 15.7% and 16.5% are expected for the 1.62 eV InGaP and 1.1 eV InGaAs cells grown on buffered GaAs. The dual junction cell has a projected one-sun AM0 conversion efficiency of 17%. The projected efficiencies are based upon the application of an optimized anti-reflective coating (ARC) to the as-grown cells. Quantum efficiency (QE) data obtained from the dual junction cell indicate that is is bottom cell current limited with the top cell generating 50% more current than the bottom cell. A comparison of the QE data for the stand-alone 1.1 eV InGaAs cell to that of the 1.1 eV InGaAs bottom cell in the tandem configuration indicates a degradation of the bottom cell conversion efficiency in the tandem configuration. The origin of this performance degradation is at present unknown. If the present limitation can be overcome, then a one-sun AM0 efficiency of 26% is achievable with the 1.62 eV/1.1 eV dual junction cell grown lattice-mismatched to GaAs
Compensating control participants when the intervention is of significant value: experience in Guatemala, India, Peru and Rwanda
The Household Air Pollution Intervention Network (HAPIN) trial is a randomised controlled trial in Guatemala, India, Peru and Rwanda to assess the health impact of a clean cooking intervention in households using solid biomass for cooking. The HAPIN interventionâa liquefied petroleum gas (LPG) stove and 18-month supply of LPGâhas significant value in these communities, irrespective of potential health benefits. For control households, it was necessary to develop a compensation strategy that would be comparable across four settings and would address concerns about differential loss to follow-up, fairness and potential effects on household economics. Each site developed slightly different, contextually appropriate compensation packages by combining a set of uniform principles with local community input. In Guatemala, control compensation consists of coupons equivalent to the LPG stoveâs value that can be redeemed for the participantâs choice of household items, which could include an LPG stove. In Peru, control households receive several small items during the trial, plus the intervention stove and 1âmonth of fuel at the trialâs conclusion. Rwandan participants are given small items during the trial and a choice of a solar kit, LPG stove and four fuel refills, or cash equivalent at the end. India is the only setting in which control participants receive the intervention (LPG stove and 18 months of fuel) at the trialâs end while also being compensated for their time during the trial, in accordance with local ethics committee requirements. The approaches presented here could inform compensation strategy development in future multi-country trials
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