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

Adherence to antiretroviral therapy, virologic failure and workload at the Rustenburg Provincial Hospital

Background: Adherence to antiretroviral therapy (ART) is a strong predictor of progression to AIDS and death. It remains the most important potentially alterable factor that determines treatment outcomes.Methods: The study is a cross-sectional survey of self-reported adherence to ART and associated factors. It included a randomly selected sample of 100 adult patients who began ART between June 2006 and December 2007. A modified Adult AIDS Clinical Trials Group questionnaire was used. The analysis compared self-reported adherence levels by factor and viral load test results.Results: Only 71% of patients had an adherence > 95%. Poor adherence was related to changes in daily routines (being away from home [21%] and busy with other things [17%]). All patients with symptoms suggestive of clinical depression had virologic failure. More unemployed patients (50.7%) had virologic failure than did employed patients (40%) (p = < 0.05). The clinic had a tenfold increase in patient enrolment and a ninefold decline in staff-to-patient ratio, and the proportion of patients lost to follow-up doubled in the preceding four years.Conclusion: Adherence to ART was poor. The capacity of the clinic to manage patients adequately has declined significantly. Decentralisation of ART services to primary health care facilities should be considered.Keywords: adherence; ART; HIV; human resource; South Afric

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

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

Synthetic schemes were developed and optimized for twelve new monomers possessing unique structural features and one aspartimide. Two synthetic pathways were compared for preparation of the triarylethane monomers with pendent ethynyl groups. The results show that one of these pathways can be generally applied. The alternative pathway was applicable to the preparation of only one of the twelve compounds, the problem being secondary reactions of the initially formed desired product

How Do Student and School Characteristics Influence Youth Academic Performance in Ghana? A Hierarchical Linear Modeling of Baseline Data From the YouthSave Ghana Experiment

Student and school characteristics are associated with academic performance of high school students. However, few attempts have been made to examine the simultaneous influence of student and school factors on academic performance of youth in sub-Saharan Africa. Using hierarchical linear modeling, we examine student- and school- level predictors of academic performance of Ghanaian junior high school students. As other researchers have found, we note that age and gender are significant predictors of academic performance. Student traits, including academic self-efficacy and commitment to school, are positively associated with math and English scores. Class size and presence of a toilet facility are significant predictors of English scores. No school-level characteristic is significantly associated with math performance. Through this study, we suggest that student characteristics have more impact on youth’s academic performance than school characteristics

The Impact of Household Possessions on Youth\u27s Academic Achievement in the Ghana YouthSave Experiment

Households play an important role in youth’s academic achievement. Household assets as part of youth’s family background have been found to have a significant impact on youth’s academic achievement. In this study, the impact of household possessions on youth’s academic achievement in the Ghana YouthSave experiment is investigated. Findings support the hypothesized positive direction of the impact of household possessions on academic achievement of youth. Using propensity score optimal matching and matching estimators, results show youth from households that reported owning at least one of the five household items measured scored almost 1 unit higher on English than their peers from households that do not own any. However, results indicate ownership of household possessions do not have a statistically significant impact on Math scores of youth in the Ghana YouthSave experiment. Although the impact of ownership of household possessions on English scores is consistent across different tests used in this study, the impact of ownership of household possessions on Math scores is less conclusive. Policy implications are discussed

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