EXPLORING THE PARADOX OF RWANDAN AGRICULTURAL HOUSEHOLD INCOME AND NUTRITIONAL OUTCOMES IN 1990 AND 2000

Nationally representative surveys regarding sources of income among agricultural households in Rwanda, fielded in 1990 and 2000, provide insights into how families responded to changes in their environment in a turbulent decade. Despite political upheavals and increasing land pressure, the survey evidence suggests that by 2000 average incomes returned to the 1990 level, while the nutritional status among rural children was better in 2000 than in the early 1990s. The nutrition improvement is tempered by evidence of increasing rural inequality. While the least poor households expanded their access to income through skilled labor, the majority of households retreated into a more autarkic mode of production focused on key subsistence crops. The change in crop mix seems to be associated with the improved the nutritional status of children. This has important implications for the current agricultural commercialization strategy in Rwanda and other countries where similar conditions prevail.Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

Analytical expressions for the envelope binding energy of giants as a function of basic stellar parameters

The common-envelope (CE) phase is an important stage in the evolution of binary stellar populations. The most common way to compute the change in orbital period during a CE is to relate the binding energy of the envelope of the Roche-lobe filling giant to the change in orbital energy. Especially in population-synthesis codes, where the evolution of millions of stars must be computed and detailed evolutionary models are too expensive computationally, simple approximations are made for the envelope binding energy. In this study, we present accurate analytic prescriptions based on detailed stellar-evolution models that provide the envelope binding energy for giants with metallicities between Z = 10-4 and Z = 0.03 and masses between 0.8 Msun and 100 Msun, as a function of the metallicity, mass, radius and evolutionary phase of the star. Our results are also presented in the form of electronic data tables and Fortran routines that use them. We find that the accuracy of our fits is better than 15% for 90% of our model data points in all cases, and better than 10% for 90% of our data points in all cases except the asymptotic giant branches for three of the six metallicities we consider. For very massive stars (M > 50 Msun), when stars lose more than ~20% of their initial mass due to stellar winds, our fits do not describe the models as accurately. Our results are more widely applicable - covering wider ranges of metallicity and mass - and are of higher accuracy than those of previous studies

Measuring human wellbeing: A protocol for selecting local indicators

Improving human wellbeing is a major focus of international environmental and sustainable development policy. However, clearly defined measures of wellbeing are needed as an empirical base for the formulation and evaluation of policies. Despite conceptual progress towards agreement of universally relevant dimensions of wellbeing, consensus is still lacking on how to translate these dimensions into locally appropriate indicators to measure wellbeing in different contexts. This paper focuses on three interrelated challenges associated with this knowledge gap: (1) navigating trade-offs between complexity versus simplicity of concept; (2) integrating top-down and bottom-up perspectives; (3) ensuring a cost-effective and flexible approach suitable for different policy contexts. We contribute to filling this gap by developing a step-by-step Wellbeing Indicator Selection Protocol (WISP) for measuring wellbeing. The protocol integrates perspectives through an interdisciplinary mixed methods design that includes cross-validation between quantitative approaches of redundancy analysis and statistical modelling and qualitative approaches of focus groups and thematic analysis. In this way we promote a pragmatic approach suitable for a range of social and environmental contexts. We tested WISP in rural Tanzania, identifying 111 candidate wellbeing indicators. This list was simplified to a subset of 19 indicators that retained 91 % of measured variation among all wellbeing indicators. The simplified list was representative of both a multidimensional concept of wellbeing and the diversity of opinions sampled. We conclude that the protocol provides practical, statistically validated guidance to support the design of wellbeing assessments, maintaining coherence between universal theory and local realities

Group Dynamics in Inquiry-based Labs: Gender Inequities and the Efficacy of Partner Agreements

Recent studies provide evidence that social constructivist pedagogical methods such as active learning, interactive engagement, and inquiry-based learning, while pedagogically more effective, can exacerbate inequities in the classroom. By conducting a quantitative empirical examination of gender-inequitable group dynamics in two inquiry-based physics labs, we extend results of previous work. Using a survey on group work preferences and video recordings of lab sessions, we find similar patterns of gendered role-taking noted in prior studies. These results are not reducible to differences in students' preferences. We find that an intervention which employed partner agreement forms, with the goal of reducing inequities, had mixed impact on students' behavior. Our work will inform implementation of more effective interventions in the future and emphasizes challenges faced by instructors who are dedicated to both research-based pedagogical practices and efforts to promote diversity, equity, and inclusion in their classrooms.Comment: 22 pages, 8 figure

Total and tropospheric ozone changes: observations and numerical modelling

A survey has been made of total and tropospheric ozone dynamics in the context of its impacts on climate, human health and ecosystems. Observation data on total ozone content (TOZ) in the atmosphere and relevant numerical modelling results have been discussed as well as similar information for tropospheric ozone, whose formation and changes are being determined by quite different causes. A necessity has been emphasized to get more adequate global observational data on TOZ and tropospheric ozone (this is especially important in the latter case, because information on tropospheric ozone is far from being complete). Unsolved problems relevant to both total and tropospheric ozone have been briefly considered