Does geographic targeting of nutrition interventions make sense in cities?

Although most developing country cities are characterized by pockets of substandard housing and inadequate service provision, it is not known to what degree low incomes and malnutrition are confined to specific neighborhoods. This analysis uses representative household surveys of Abidjan and Accra to quantify small-area clustering in service provision, demographic characteristics, consumption, and nutrition. Both cities showed significant clustering in housing conditions but not in nutrition, while income was clustered in Abidjan, but less so in Accra. This suggests that neighborhood targeting of poverty-alleviation or nutrition interventions in these and similar cities could lead to undercoverage of the truly needy.Food consumption. ,Human Nutrition. ,Urban poor Africa. ,Malnutrition Africa. ,Africa. ,

The constraints to good child care practices in Accra

Life in urban areas presents special challenges for maternal child care practices. Data from a representative survey of households with children less than 3 years of age in Accra were used to test a number of hypothesized constraints to child care, including various maternal (education, employment, marital status, age, health, ethnic group, migration status) and household-level factors (income, calorie availability, quality of housing and asset ownership, availability of services, household size, and crowding). An age-specific child care index was created using recall data on maternal child feeding practices and use of preventive health services. A hygiene index was created from spot check observations of proxies of hygiene behaviors. Multivariate analyses showed that maternal schooling was the most consistent constraint to both the care and the hygiene index. None of the household-level characteristics were associated with the care index, but better housing quality and access to garbage collection services were associated with better hygiene. Female head of household and larger family size were associated with poorer hygiene. The programmatic implications of these findings for nutrition education and behavior change interventions in Accra are discussed. The focus is on using the information to target the right practices to be modified as well as the main constraints to their adoption.FCND ,Child care. ,Ghana. ,Maternal and infant welfare Developing countries. ,Urban health. ,

Good care practices can mitigate the negative effects of poverty and low maternal schooling on children's nutritional status

This study uses data from a representative survey of households with preschoolers in Accra, Ghana to (1) examine the importance of care practices for children's height-for-age z-scores (HAZ); and (2) identify subgroups of children for whom good maternal care practices may be particularly important. Good caregiving practices related to child feeding and use of preventive health services were a strong determinant of children's HAZ, specially among children from the two lower income terciles and children whose mothers had less than secondary schooling. In this population, good care practices could compensate for the negative effects of poverty and low maternal schooling on children's HAZ. Thus, effective targeting of specific education messages to improve child feeding practices and use of preventive health care could have a major impact on reducing childhood malnutrition in Accra.Health services. ,Child care. ,Child Feeding. ,Poverty. ,

Vegetation and Flora of the Sand Deposits of the Mississippi River Valley in Northwestern Illinois

This study was undertaken to determine vascular plant species composition, vegetation structure, and floristic quality of the major plant communities in the windblown sand deposits of northwestern Illinois during the growing seasons of 2002 through 2005. The major plant communities of the Ayers Sand Prairie Nature Preserve in Carroll County, Big River State Forest in Henderson County, Lost Mound Unit of the Upper Mississippi River Wildlife and Fish Refuge in Carroll and Jo Daviess counties, and the Thomson-Fulton Sand Prairie Nature Preserve located in Whiteside County were examined and the importance values determined for the plant species present. Located on broad terraces of the Mississippi River, these nature preserves and natural areas are remnants of a larger grassland/savanna/forest complex that contained extensive marsh; wet, mesic, and dry sand prairie; sand savanna; and sand forest communities. Most of the sand deposits are now cultivated and the original vegetation is found only in protected remnants, some of which are relatively large. The mature dry sand prairies were dominated by Schizachyrium scoparium; other important species were Opuntia macrorhiza, Dichanthelium villosissimum, Ambrosia psilostachya, and Tephrosia virginiana. Other assemblages of prairie and exotic species were encountered in successional sand prairie communities. Generally, the mature prairie communities in these preserves and natural areas had 35 or more species present in the study plots. Savanna and closed canopy forest communities were also examined. The dry sand savannas were dominated by Quercus velutina and Q. marilandica, dry sand forests were dominated by Q. velutina, and dry-mesic sand forests were dominated by Q. alba and Q. velutina.Illinois Department of Natural Resources; Illinois Nature Preserves Commissionpublished or submitted for publicationis peer reviewe

Complex bounds for multimodal maps: bounded combinatorics

We proved the so called complex bounds for multimodal, infinitely renormalizable analytic maps with bounded combinatorics: deep renormalizations have polynomial-like extensions with definite modulus. The complex bounds is the first step to extend the renormalization theory of unimodal maps to multimodal maps.Comment: 20 pages, 3 figure

Fabricating BRDFs at high spatial resolution using wave optics

Recent attempts to fabricate surfaces with custom reflectance functions boast impressive angular resolution, yet their spatial resolution is limited. In this paper we present a method to construct spatially varying reflectance at a high resolution of up to 220dpi, orders of magnitude greater than previous attempts, albeit with a lower angular resolution. The resolution of previous approaches is limited by the machining, but more fundamentally, by the geometric optics model on which they are built. Beyond a certain scale geometric optics models break down and wave effects must be taken into account. We present an analysis of incoherent reflectance based on wave optics and gain important insights into reflectance design. We further suggest and demonstrate a practical method, which takes into account the limitations of existing micro-fabrication techniques such as photolithography to design and fabricate a range of reflection effects, based on wave interference.United States-Israel Binational Science FoundationIntel Corporation (Intel Collaborative Research Institute for Computational Intelligence)National Science Foundation (U.S.) (CGV 1116303

Effect of frequent hemodialysis on residual kidney function.

Frequent hemodialysis can alter volume status, blood pressure, and the concentration of osmotically active solutes, each of which might affect residual kidney function (RKF). In the Frequent Hemodialysis Network Daily and Nocturnal Trials, we examined the effects of assignment to six compared with three-times-per-week hemodialysis on follow-up RKF. In both trials, baseline RKF was inversely correlated with number of years since onset of ESRD. In the Nocturnal Trial, 63 participants had non-zero RKF at baseline (mean urine volume 0.76 liter/day, urea clearance 2.3 ml/min, and creatinine clearance 4.7 ml/min). In those assigned to frequent nocturnal dialysis, these indices were all significantly lower at month 4 and were mostly so at month 12 compared with controls. In the frequent dialysis group, urine volume had declined to zero in 52% and 67% of patients at months 4 and 12, respectively, compared with 18% and 36% in controls. In the Daily Trial, 83 patients had non-zero RKF at baseline (mean urine volume 0.43 liter/day, urea clearance 1.2 ml/min, and creatinine clearance 2.7 ml/min). Here, treatment assignment did not significantly influence follow-up levels of the measured indices, although the range in baseline RKF was narrower, potentially limiting power to detect differences. Thus, frequent nocturnal hemodialysis appears to promote a more rapid loss of RKF, the mechanism of which remains to be determined. Whether RKF also declines with frequent daily treatment could not be determined

Assessing the burden of COVID-19 in developing countries: systematic review, meta-analysis and public policy implications

Trabajo realizado por otros catorce autores.Introduction The infection fatality rate (IFR) of COVID-19 has been carefully measured and analysed in high-income countries, whereas there has been no systematic analysis of age-specific seroprevalence or IFR for developing countries. Methods We systematically reviewed the literature to identify all COVID-19 serology studies in developing countries that were conducted using representative samples collected by February 2021. For each of the antibody assays used in these serology studies, we identified data on assay characteristics, including the extent of seroreversion over time. We analysed the serology data using a Bayesian model that incorporates conventional sampling uncertainty as well as uncertainties about assay sensitivity and specificity. We then calculated IFRs using individual case reports or aggregated public health updates, including age pecific estimates whenever feasible. Results In most locations in developing countries, seroprevalence among older adults was similar to that of younger age cohorts, underscoring the limited capacity that these nations have to protect older age groups. Age-specific IFRs were roughly 2 times higher than in high income countries. The median value of the population IFR was about 0.5%, similar to that of high-income countries, because disparities in healthcare access were roughly offset by differences in population age structure. Conclusion The burden of COVID-19 is far higher in developing countries than in high-income countries, reflecting a combination of elevated transmission to middle-aged and older adults as well as limited access to adequate healthcare. These results underscore the critical need to ensure medical equity to populations in developing countries through provision of vaccine doses and effective medications

Cosmological Challenges in Theories with Extra Dimensions and Remarks on the Horizon Problem

We consider the cosmology that results if our observable universe is a 3-brane in a higher dimensional universe. In particular, we focus on the case where our 3-brane is located at the $Z_2$ symmetry fixed plane of a $Z_2$ symmetric five-dimensional spacetime, as in the Ho\v{r}ava-Witten model compactified on a Calabi-Yau manifold. As our first result, we find that there can be substantial modifications to the standard Friedmann-Robertson-Walker (FRW) cosmology; as a consequence, a large class of such models is observationally inconsistent. In particular, any relationship between the Hubble constant and the energy density on our brane is possible, including (but not only) FRW. Generically, due to the existence of the bulk and the boundary conditions on the orbifold fixed plane, the relationship is not FRW, and hence cosmological constraints coming from big bang nucleosynthesis, structure formation, and the age of the universe difficult to satisfy. We do wish to point out, however, that some specific choices for the bulk stress-energy tensor components do reproduce normal FRW cosmology on our brane, and we have constructed an explicit example. As our second result, for a broad class of models, we find a somewhat surprising fact: the stabilization of the radius of the extra dimension and hence the four dimensional Planck mass requires unrealistic fine-tuning of the equation of state on our 3-brane. In the last third of the paper, we make remarks about causality and the horizon problem that apply to {\it any} theory in which the volume of the extra dimension determines the four-dimensional gravitational coupling. We point out that some of the assumptions that lead to the usual inflationary requirements are modified.Comment: 15 page REVTeX file; to appear in Phys. Rev. D; clarified the statement of being able to obtain any power dependence of the Hubble expansion rate on the energy density; added reference