AN ANALYSIS OF THE MARKET FOR FOOD STAMPS

Food Security and Poverty,

Review of the economics of family time use

Journal ArticleTime is a limited resource. Yet, it is also the one resource with which all individuals are equally endowed on any given day. Why then is there such wide variation in how each of us chooses to use that time? What factors guide our decisions about time spent working versus time spent with family and friends? Why is it that activity patterns vary by gender, education level, and life cycle stage? In this essay, we review the economic model of household production that has been applied to investigations of family time use and summarize the insights that have been gained from the empirical tests of this model

Does housework matter anymore? The shifting impact of housework on economic inequality

Working PaperIn recent years, American women's housework time has declined while American men's housework time has risen. We examine how these changes have affected economic inequality in America. Using time-diary data from the Time Use in Economic and Social Accounts, 1975-76 (N=1,484) and the American Time Use Survey, 2003 (N=5,534), we assess the economic value of adults' housework and its influence on households' real access to goods and services in both years. Results suggest that housework reduces economic inequality. But, between 1975-76 and 2002-03, economic inequality rose largely because of the growing money income inequality and also, in part, because of modest growth in housework nequality. Demographic change, principally the rise in women's employment, partially inhibited the growth in inequality

Time use choices and healthy body weight: A multivariate analysis of data from the American Time use Survey

<p>Abstract</p> <p>Background</p> <p>We examine the relationship between time use choices and healthy body weight as measured by survey respondents' body mass index (BMI). Using data from the 2006 and 2007 American Time Use Surveys, we expand upon earlier research by including more detailed measures of time spent eating as well as measures of physical activity time and sedentary time. We also estimate three alternative models that relate time use to BMI.</p> <p>Results</p> <p>Our results suggest that time use and BMI are simultaneously determined. The preferred empirical model reveals evidence of an inverse relationship between time spent eating and BMI for women and men. In contrast, time spent drinking beverages while simultaneously doing other things and time spent watching television/videos are positively linked to BMI. For women only, time spent in food preparation and clean-up is inversely related to BMI while for men only, time spent sleeping is inversely related to BMI. Models that include grocery prices, opportunity costs of time, and nonwage income reveal that as these economic variables increase, BMI declines.</p> <p>Conclusions</p> <p>In this large, nationally representative data set, our analyses that correct for time use endogeneity reveal that the Americans' time use decisions have implications for their BMI. The analyses suggest that both eating time and context (i.e., while doing other tasks simultaneously) matters as does time spent in food preparation, and time spent in sedentary activities. Reduced form models suggest that shifts in grocery prices, opportunity costs of time, and nonwage income may be contributing to alterations in time use patterns and food choices that have implications for BMI.</p

Durability Characterization of Mechanical Interfaces in Solar Sail Membrane Structures

The construction of a solar sail from commercially available metallized film presents several challenges. The solar sail membrane is made by seaming together strips of metallized polymer film. This requires seaming together a preselected width and thickness of a base material into the required geometry, and folding the assembled sail membranes into a small stowage volume prior to launch. The sail membranes must have additional features for connecting to rigid structural elements (e.g., sail booms) and must be electrically grounded to the spacecraft bus to prevent charge build up. Space durability of the material and mechanical interfaces of the sail membrane assemblies will be critical for the success of any solar sail mission. In this study, interfaces of polymer/metal joints in a representative solar sail membrane assembly were tested to ensure that the adhesive interfaces and the fastening grommets could withstand the temperature range and expected loads required for mission success. Various adhesion methods, such as surface treatment, commercial adhesives, and fastening systems, were experimentally evaluated and will be discussed

Discharge characteristics at bioswale installation sites along I-294 in northern Cook County, Illinois

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PARP-3 and APLF function together to accelerate nonhomologous end joining

PARP-3 is a member of the ADP-ribosyl transferase superfamily of unknown function. We show that PARP-3 is stimulated by DNA double-strand breaks (DSBs) in vitro and functions in the same pathway as the poly (ADP-ribose)-binding protein APLF to accelerate chromosomal DNA DSB repair. We implicate PARP-3 in the accumulation of APLF at DSBs and demonstrate that APLF promotes the retention of XRCC4/DNA ligase IV complex in chromatin, suggesting that PARP-3 and APLF accelerate DNA ligation during nonhomologous end-joining (NHEJ). Consistent with this, we show that class switch recombination in Aplf−/− B cells is biased toward microhomology-mediated end-joining, a pathway that operates in the absence of XRCC4/DNA ligase IV, and that the requirement for PARP-3 and APLF for NHEJ is circumvented by overexpression of XRCC4/DNA ligase IV. These data identify molecular roles for PARP-3 and APLF in chromosomal DNA double-strand break repair reactions

The effects of bioswale construction on groundwater adjacent to I-294 in northern Cook County, Illinois

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Reductions in turbidity and specific conductivity in runoff treated by bioswales along I-294 in northern Cook County, Illinois

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