The synthesis of monomers with pendent ethynyl group for modified high performance thermoplastics

The objectives of this project were to develop synthetic schemes for the following classes of modified monomers: (1) difunctional triarylethanes with pendent acetylenic groups; and (2) tertiary aspartimides with terminal acetylene groups at the two ends. Our efforts have resulted in the successful development of high yield schemes for the syntheses of several diamino and bisphenolic analogs of difunctional triarylethanes with pendent ethynyl group. A scheme for one new tertiary aspartimide was also established. Multi-gram samples of all prepared new monomers were provided to our technical contact at NASA-LaRC and preliminary polymerization studies were encouraging. Details of the accomplished work within the last four years are described

Bayesian modeling of space and time dynamics: A practical demonstration in social and health science research

Objective: This article introduces Bayesian spatial–temporal modeling for social and health science research. We use the World Bank’s World Development Indicators data on youth unemployment and HIV risk in Africa to illustrate the utility of the Bayesian paradigm in modeling space–time changes in outcomes. Method: Data on adolescents and young adults were collected in 36 African countries from 1991 to 2014. We examined associations between HIV risk and youth unemployment rates using 16 Bayesian Poisson models incorporating spatial and temporal autocorrelations. Results: The best fit to the data was the model with spatially uncorrelated heterogeneity, temporally correlated random-walk autocorrelation, and spatial–temporal interaction. HIV risk factors are spatially uncorrelated across 36 countries but temporally correlated (i.e., country and time interaction) over the data collection period. The relationship between HIV risk and unemployment rate is statistically nonsignificant because of large spatial–temporal variations. Conclusions: This article demonstrates the capacity of Bayesian modeling to incorporate spatial (neighborhood) and temporal (historical) information to reflect not only the influences of space and time but also their interactions on the phenomenon of interest. The Bayesian framework holds great promise for improving the dynamic targeting of interventions and strategies to achieve desired outcomes

Hospital based maternity care in Ghana - findings of a confidential enquiry into maternal deaths

Background: In Ghana, a universal free delivery policy was implemented to improve access to delivery care in health facilities, thereby improving access to skilled attendance and reducing maternalmortality. Objective: A confidential enquiry was conducted to ascertain if changes had occurred in the care provided by reviewing the care given to a sample of maternal deaths before and after introduction of the policy. Method: Twenty women who died as a result of pregnancy-related complications (maternal deaths) in selected hospitals in two regions were assessed by a clinical panel, guided by a maternal deathassessment form. Unlike the traditional confidential enquiry process, both adverse and favourable factors were identified. Findings: Clinical care provided before and after the introduction of the fee exemption policy did not change, though women with complications were arriving in hospital earlier after the introduction of the policy. On admission, however, they received very poor care and this, the clinical paneldeduced could have resulted in many avoidable deaths; as was the case before the implementation of the policy. Consumables, basic equipment and midwifery staff for providing comprehensive emergency obstetric care were however found to be usually available. Conclusion: Our findings suggest that the already poor delivery care services women received remained unchanged after introduction of the policy

Introducing the Disease Outbreak Resilience Index (DORI) Using the Demographic and Health Surveys Data from sub-Saharan Africa

Although most studies on disease emergencies underscore the need for household readiness for shocks associated with disease outbreaks, no study to date has provided a holistic measure for profiling households based on their readiness toward disease outbreaks. This paper introduces a novel Disease Outbreak Resilience Index (DORI) using a multidimensional approach that draws on the Alkire-Foster methodology. DORI measures disease outbreak resilience in four dimensions: (a) water and hygiene, (b) physical distancing, (c) energy and communication, and (d) economic security and resilience. The paper details the development of DORI and its use by presenting findings from ten countries in sub-Saharan Africa using data from the Demographic and Health Surveys (DHS) program. In addition to serving as a resilience index, we illustrate how DORI can be used to produce a disease outbreak vulnerability index (DOVI). As a versatile index, the indicators under each dimension can be tailored to meet country- and region-specific contexts based on indicators appropriate to each context

Cross-Cultural Adaptation and Validation of the Commitment-to-School Scale Using a Sample of Junior High School Youth in Ghana

Empirical evidence from developed countries suggests that students' commitment to school is fundamental to their academic success. However, in developing countries, validated measures of student commitment to school do not exist. The current study helps fill this research gap by examining the validity and reliability of a commitment-to-school scale (CSS) adapted for the Ghanaian context. With a sample of 6,252 middle school–age students, the study employs exploratory and confirmatory factor analyses with weighted least squares means and variance adjusted (WLSMV) to establish and validate the construct as bidimensional. Measurement invariance tests confirm that the two-factor commitment model is generalizable across grade levels but not genders. Given its parsimony and good fit, the adapted CSS might be useful for future research in Ghana. Similarity of the model across grade levels suggests that the scale has potential uses in education research among diverse groups. We suggest that the CSS be developed further for better understanding of students' commitment to school

Junior high school students’ use of their afterschool hours in Ghana: The role of household assets

Studies have examined a broad range of factors for how students use their time, but few attempts have been made to explore the nuanced link between different types of asset ownership and students' use of study time, particularly in resource-limited countries. This study uses data from junior high school students in Ghana to examine how students spend their time after school hours, the predictive influence of different types of household assets, and the extent to which these trends and relationships vary by gender. Polynomial quantile regression models were fitted across three quantiles (24th, 53rd, and 76th percentiles) to align with one hour, one and half hours, and two hours of study time. Results show that the average student spends well above the recommended 90 minutes on their schoolwork during afterschool hours, regardless of gender. Multivariate results indicate that owning limited assets tends to have a negative relationship with use of study time, but higher levels tend to be positively related to use of study time. Also, the predictive influence of asset ownership varies by asset type, and higher levels of asset ownership favor girls more than boys. Given this study's realtively small sample size, caution must be exercised in generalizing the study findings to the general population of junior high school students in Ghana. In light of the study's limitations, the finding of varying asset effect may have practical implications for asset development programs designed to enhance the well-being of low-income families

Evidence building and information accumulation: Using the bayesian paradigm to advance child welfare intervention research

Objective: Intervention evaluation typically follows a frequentist paradigm: New analyses are conducted for each subsequent study, and findings are then used to improve policy practice. This approach largely ignores data from prior studies, leading to information loss and incomplete or inaccurate conclusions. Unlike the frequentist paradigm, the Bayesian paradigm uses formative data (as pri-ors), which can be updated with the summative data, thus building on existing evidence about an intervention’s effectiveness. Method: This article uses data from the Safe Families for Children randomized controlled trial to illustrate how the Bayesian paradigm incorporates prior evidence at the formative phase with data at the summative phase to provide a more comprehensive analysis. This approach is consistent with the scientific principle of evidence building. We compare the merits of each paradigm on two evaluation criteria: (a) p-values from a chi-square test, and (b) the probability that the intervention is superior to the comparison group on three outcome variables (protective custody, deflection from foster care, and whether repeat victimization occurred). Results: The Bayesian paradigm consistently outperformed the frequentist paradigm. Conclusion: The Bayesian paradigm is superior to the frequentist paradigm in demonstrating the effectiveness of an intervention, as evidenced by smaller p-values and a higher probability that the intervention group outperformed the comparison group

The importance of self-efficacy and educational aspirations for academic achievement in resource-limited countries: Evidence from Ghana

Introduction: Research on the influence of academic self-efficacy and educational aspirations on academic performance is underdeveloped in resource-limited countries. This study replicates and expands on earlier research that investigated a complex network of relationships between academic self-efficacy, educational aspirations, and academic performance. Methods: Data from 4282 adolescents in Ghana and path analysis were used to test the causal pathways, and path invariance analysis was used to assess the moderation role of gender. Instrumental variable techniques were used to validate the path models. Results: Increase in academic self-efficacy indirectly accounts for improvement in academic performance through the mediational role of educational aspirations. The effects of self-efficacy on educational aspirations, and educational aspirations were stronger for boys than for girls. Conclusions: These findings suggest that in resource-limited countries where the financial burden of schooling tends to be a demotivating factor, interventions that target adolescents' academic self-efficacy may be an effective means to boost educational aspirations and academic performance. Interventions should be tailored to meet the needs of all students so that all children can think of school as an important part of their lives and aspire to achieve, now and in the future

Determinants of saving among low-income individuals in rural Uganda: Evidence from AssetsAfrica.

Although research has shown that poor people in sub-Saharan Africa (SSA), including those living in rural areas save, little is known about the factors that influence saving and asset accumulation among this population. Using three theoretical perspectives on saving and asset accumulation, this study examines the broader determinants of saving and asset accumulation among low-income individuals in rural Uganda. Compared with the individual-oriented and sociological perspectives, institutional theory explains a large part of the variance in saving outcome among rural, low-income households. Wealth, proximity to financial institutions, financial education, and financial incentives are positively associated with higher saving performance. Findings suggest that poor people can and do save, particularly when institutional barriers to saving are removed. Institutional structures, which encourage low-income individuals to save, may contribute to a poverty reduction policy that shifts from just income supplementation to a more inclusive wealth promotion policy that assists people in creating their own pathways out of poverty