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In Sub-Saharan Africa rapid urban growth combined with rising poverty is creating diverse urban environments, the nature of which are not adequately captured by a simple urban-rural dichotomy. This paper proposes an alternative classification scheme for urban mapping based on a gradient approach for the southern portion of the West African country of Ghana. Landsat Enhanced Thematic Mapper Plus (ETM+) and European Remote Sensing Satellite-2 (ERS-2) synthetic aperture radar (SAR) imagery are used to generate a pattern based definition of the urban context. Spectral mixture analysis (SMA) is used to classify a Landsat scene into Built, Vegetation and Other land covers. Landscape metrics are estimated for Built and Vegetation land covers for a 450 meter uniform grid covering the study area. A measure of texture is extracted from the SAR imagery and classified as Built/Non-built. SMA based measures of Built and Vegetation fragmentation are combined with SAR texture based Built/Non-built maps through a decision tree classifier to generate a nine class urban context map capturing the transition from unsettled land at one end of the gradient to the compact urban core at the other end. Training and testing of the decision tree classifier was done using very high spatial resolution reference imagery from Google Earth. An overall classification agreement of 77% was determined for the nine-class urban context map, with user's accuracy (commission errors) being lower than producer's accuracy (omission errors). Nine urban contexts were classified and then compared with data from the 2000 Census of Ghana. Results suggest that the urban classes appropriately differentiate areas along the urban gradient.

Human migration has been identified as a potential factor for increased Chagas disease risk and has transformed the disease from a Latin American problem to a global one. We conducted a systematic review of the scientific literature between 2004-2014 in order to: summarize recent seroprevalence estimates of Chagas disease among Latin American migrants, in both endemic and non-endemic settings; compare seroprevalence estimates in migrants to countrywide prevalence estimates; and identify risk factors for Chagas disease among migrants. A total of 320 studies were screened and 23 studies were included. We found evidence that the prevalence of Chagas disease is higher than expected in some migrant groups and that reliance on blood donor screening prevalence estimates underestimates the burden of disease. Overall there is a dearth of high quality epidemiologic studies on the prevalence of Chagas disease in migrants, especially among intra-regional migrants within Latin America. Given that this zoonotic disease cannot likely be eradicated, improved surveillance and reporting is vital to continuing control efforts. More accurate health surveillance of both Latin American migrants and the Chagas disease burden will help countries appropriately scale up their response to this chronic disease. Overall, improved estimates of Chagas disease among migrants would likely serve to highlight the real need for better screening, diagnostics, and treatment of individuals living with the disease.

Research has pointed to an apparent public health enigma among new immigrants to the United States: high-risk groups, particularly low-income immigrants from Mexico and Southeast Asia, show unexpectedly favorable perinatal outcomes and seem to be “superior health achievers.” This study attempts to unravel the reasons for this “epidemiological paradox” by examining an in-depth data set drawn from a Comprehensive Perinatal Program (CPP) in San Diego County providing prenatal care services to low-income pregnant women, most of whom were immigrants from Mexico and various Asian countries, The CPP data set consists of nearly 500 independent variables per case (including most of those listed in the research literature as likely biomedical and sociocultural determinants of pregnancy outcomes) for a sample of both foreign-born and U.S.-born women, matched to infant health outcome measures collected from hospital records for every baby delivered by CPP mothers during 1989-1991. The analysis focuses on the identification of maternal risk factors that best explain observed ethnic and/or nativity differences in pregnancy outcomes (birth weight, diagnoses at birth, complications, length of hospitalization of the baby). Asians and Hispanics (mostly foreign-born) had superior outcomes relative to Anglos and African-Americans (mostly native-born); within ethnic groups outcomes were generally better for immigrants than for natives; and for immigrants outcomes worsened as the general acculturation or “Americanization” of the mother increased. The comparative socioeconomic advantages of US-born women – in education, employment, income, English literacy and proficiency – appeared to be overwhelmed by biomedical, nutritional and psychosocial disadvantages. In multivariate analyses, ten independent variables – a set of both biomedical and sociocultural factors – remained as significant predictors of pregnancy outcomes. Four qualitative case histories of CPP mothers are drawn from psychosocial reports to shed further light on the quantitative findings drawn from the statistical analysis. Limitations and implications of this study for health policy and future research are considered.

Purpose: The purpose of this paper is threefold: first, to introduce a conceptual model for assessing undergraduate student learning outcomes and satisfaction that involves concepts drawn from the services marketing and assessment literatures; second, to illustrate the utility of the model as implemented in an academic department (geography) within a large American university, and third, to demonstrate the applicability of the model by replicating the study at different scales: an entire undergraduate program (business administration) in a large Spanish university and another program (nursing) involving various universities of a Spanish region. Design/methodology/approach: A multi-method approach is used which comprises quadrant analysis, ANOVA tests and structural equation modeling techniques. A questionnaire was designed for data collection. Findings: The main finding is the support found for the proposed model at different scales. Results of the multi-method approach provide specific guidelines to departments using this approach to improve student learning outcomes and satisfaction. Practical implications: The paper provides a conceptual model and supporting tools that can be used by other academic departments or higher education institutions to assist in the evaluation of how students perceive their learning outcomes and satisfaction with their undergraduate program. Originality/value: The value of this multi-method approach is that it is simple to implement, and at the same time provides a richness of information for diagnosis and decision-making. The model was tested with data collected in different undergraduate programs and different countries, allowing the authors not only to find support for the model, but also to consider cultural differences among student perceptions. (Contains 3 figures, 9 tables, and 3 notes.)