Bargaining power, decision making, and biofortification: The role of gender in adoption of orange sweet potato in Uganda.

We examine the role of gender dimensions of intrahousehold bargaining power and decision making in the adoption and diffusion of orange sweet potato (OSP), a biofortified crop being promoted to increase dietary intakes of vitamin A in Uganda. We use patterns of ownership and control of land and other assets by married men and women to create gender-disaggregated indicators of bargaining power, allowing for joint and sole ownership and control of land and assets. Using data from an experimental evaluation of a project promoting OSP adoption, we find that the probability of adopting OSP is not affected by the exclusive or joint control of assets by women at the household level. However, within households, parcels of land under joint control, in which the woman has primary control over decision making, are significantly more likely to contain OSP. Women who control a higher share of household nonland resources are more likely to share OPS vines, showing that women use greater bargaining power to facilitate diffusion of this health-promoting technology. We do not find any impact of women's bargaining power on children's dietary intakes of Vitamin A, possibly because husbands and wives have the same preferences regarding their children's nutritional status. These results contribute to reshaping our understanding of household decision making to inform the design and implementation of agriculture-nutrition interventions.

Quantum dot and silica nanoparticle doped polymer optical fibers.

A novel and highly versatile doping method has been developed to allow active dopants, including materials incompatible with the polymer matrix, to be incorporated into microstructured polymer optical fibers through the use of nanoparticles. The incorporation of quantum dots and silica nanoparticles containing Rhodamine isothiocyanate is demonstrated.

Sweetened food purchases and indulgent feeding are associated with increased toddler anthropometry.

OBJECTIVE: To explore the role of feeding practices and food purchases in toddler dietary intake and anthropometry. METHODS: A convenience sample of Latino mother and toddler pairs were interviewed at baseline and at 6-month follow-up. Data on feeding practices, toddler dietary intake, anthropometry, and food purchases were collected using the Toddler-Feeding Questionnaire; 24-hour recalls; measurements of weight, height, and/or length; and food purchase receipts. RESULTS: Indulgent feeding scores and high intake of sweetened beverage were associated with a 0.52 increase (P = .03) and 0.46 increase in toddler weight-for-height z-score (P = .05), respectively. Households with 10 percentage points of more sweetened food and beverage expenditures were associated with increases in weight indicator z-scores. CONCLUSIONS AND IMPLICATIONS: Indulgent feeding, high intake, and purchase of sweetened beverage are associated with weight gain in Latino toddlers. Programs should target food purchasing decisions and provide concrete guidance for the division of responsibility around feeding.

Electrostatic self-assembly of PEG copolymers onto porous silica nanoparticles.

A critical requirement toward the clinical use of nanocarriers in drug delivery applications is the development of optimal biointerfacial engineering procedures designed to resist biologically nonspecific adsorption events. Minimization of opsonization increases blood residence time and improves the ability to target solid tumors. We report the electrostatic self-assembly of polyethyleneimine-polyethylene glycol (PEI-PEG) copolymers onto porous silica nanoparticles. PEI-PEG copolymers were synthesized and their adsorption by self-assembly onto silica surfaces were investigated to achieve a better understanding of structure-activity relationships. Quartz-crystal microbalance (QCM) study confirmed the rapid and stable adsorption of the copolymers onto silica-coated QCM sensors driven by strong electrostatic interactions. XPS and FT-IR spectroscopy were used to analyze the coated surfaces, which indicated the presence of dense PEG layers on the silica nanoparticles. Dynamic light scattering was used to optimize the coating procedure. Monodisperse dispersions of the PEGylated nanoparticles were obtained in high yields and the thin PEG layers provided excellent colloidal stability. In vitro protein adsorption tests using 5% serum demonstrated the ability of the self-assembled copolymer layers to resist biologically nonspecific fouling and to prevent aggregation of the nanoparticles in physiological environments. These results demonstrate that the electrostatic self-assembly of PEG copolymers onto silica nanoparticles used as drug nanocarriers is a robust and efficient procedure, providing excellent control of their biointerfacial properties.

Temporal and spatial variation in age-specific net migration in the United States.

As fertility differences in the United States diminish, population redistribution trends are increasingly dependent on migration. This research used newly developed county-level age-specific net migration estimates for the 1990s, supplemented with longitudinal age-specific migration data spanning the prior 40 years, to ascertain whether there are clear longitudinal trends in age-specific net migration and to determine if there is spatial clustering in the migration patterns. The analysis confirmed the continuation into the 1990s of distinct net migration "signature patterns" for most types of counties, although there was temporal variation in the overall volume of migration across the five decades. A spatial autocorrelation analysis revealed large, geographically contiguous regions of net in-migration (in particular, Florida and the Southwest) and geographically contiguous regions of net out-migration (the Great Plains, in particular) that persisted over time. Yet the patterns of spatial concentration and fragmentation over time in these migration data demonstrate the relevance of this "neighborhood" approach to understanding spatiotemporal change in migration.