Application of a panel method to wake-vortex/wing interaction and comparison with experimental data

The ability of the Vortex Separation AEROdynamics (VSAERO) program to calculate aerodynamic loads on wings due to interaction with free vortices was studied. The loads were calculated for various positions of a downstream following wing relative to an upstream vortex-generating wing. Calculated vortex-induced span loads, rolling-moment coefficients, and lift coefficients on the following wing were compared with experimental results of McMillan et al. and El-Ramly et al. Comparisons of calculated and experimental vortex tangential velocities were also made

Overcoming child malnutrition in developing countries

In 1995, 167 million children under five years old—almost one-third of developing-country children—were malnourished. Malnutrition causes a great deal of human suffering, and it is a violation of a child's human rights. It is associated with more than half of all deaths of children worldwide. People who survive a malnourished childhood are less physically and intellectually productive and suffer from more chronic illness and disability. The costs to society are enormous. Eradicating malnutrition remains a tremendous public policy challenge. Which types of interventions will have the greatest impact in reducing child malnutrition? The study on which this brief is based uses national data for 63 countries over 1970–96 to explore this question. Smith and Hadded examine the determinants of child nutritional status and discuss reductions in child malnutrition during 1970–95. they forecast the status of child malnutrition to the year 2020 and sugest priorities for the future.Malnutrition in children Developing countries History. ,Malnutrition in children Developing countries Forecasting. ,

Explaining child malnutrition in developing countries

"One in three pre school children in the developing world is undernourished. As a consequence, their human rights are violated. In addition, they are more likely to have impaired immune systems, poorer cognitive development, lower productivity as adults, and greater susceptibility to diet-related chronic diseases such as hypertension and coronary heart disease later in life. Undernourished female preschoolers are likely to grow into undernourished young women who are more likely to give birth to babies who are undernourished even before they are born, thus perpetuating the inter-generational transmission of deprivation. Reducing these unacceptably high numbers remains a tremendous challenge to public policy. As a guide to the direction of future efforts, this research report examines the success of the efforts of the past 25 years to reduce preschooler undernutrition. The report uses an econometric model to identify the factors associated with the reduction in undernutrition. The formulation of the econometric model is guided by the widely accepted food-care-health conceptual model of child growth. The contributions of both underlying and basic determinants to reductions in undernutrition are assessed using the model. The potential of these factors to further reduce undernutrition is evaluated in a region-by-region priority-setting exercise. In addition, projections of child nutrition are made under various scenarios to the year 2020. What will it take to dramatically reduce undernutrition in the next 20 years? The report attempts some broad answers to these questions..." (Forward by Per Pinstrup-Andersen)Gender ,Malnutrition in children Developing countries Prevention ,Nutrition ,

Explaining child malnutrition in developing countries: a cross-country analysis

"One in three pre-school children in the developing world is undernourished. As a consequence, their human rights are violated. In addition, they are more likely to have impaired immune systems, poorer cognitive development, lower productivity as adults, and greater susceptibility to diet-related chronic diseases such as hypertension and coronary heart disease later in life. Undernourished female preschoolers are likely to grow into undernourished young women who are more likely to give birth to babies who are undernourished even before they are born, thus perpetuating the inter-generational transmission of deprivation. Reducing these unacceptably high numbers remains a tremendous challenge to public policy. As a guide to the direction of future efforts, this research report examines the success of the efforts of the past 25 years to reduce preschooler undernutrition. The report uses an econometric model to identify the factors associated with the reduction in undernutrition. The formulation of the econometric model is guided by the widely accepted food-care-health conceptual model of child growth. The contributions of both underlying and basic determinants to reductions in undernutrition are assessed using the model. The potential of these factors to further reduce undernutrition is evaluated in a region-by-region priority-setting exercise. In addition, projections of child nutrition are made under various scenarios to the year 2020. What will it take to dramatically reduce undernutrition in the next 20 years? The report attempts some broad answers to these questions..." (Forward by Per Pinstrup-Andersen)Malnutrition in children Developing countries., Malnutrition in children Developing countries Prevention., Developing countries., Econometric models., Gender, Health and nutrition,

Overcoming child malnutrition in developing countries: past achievements and future choices

"About 167 million children under five years of age —almost one-third of the developing world's children —are malnourished. If they survive childhood, many of these children will suffer from poorer cognitive development and lower productivity. As adults, their ability to assure good nutrition for their children could be compromised, perpetuating a vicious cycle. What will it take to eradicate child malnutrition in developing countries? As Lisa Smith and Lawrence Haddad point out in this 2020 Vision discussion paper, Overcoming Child Malnutrition in Developing Countries: Past Achievements and Future Choices, we must first understand the causes of malnutrition and delineate which are the most important before we can identify and act upon those areas of intervention that will be most successful in reducing malnutrition. Toward that end, their path-breaking research identifies and assesses the contribution of each key determinant to reductions in child malnutrition over the past quarter century. The most startling and important finding is that improvements in women's education have contributed by far the most, accounting for 43 percent of the reduction in child malnutrition between 1970 and 1995, while improvements in per capita food availability con tributed about 26 percent. In a signal service to policymakers, Smith and Haddad also evaluate the potential of these factors to further reduce malnutrition durng the next two decades to 2020 and lay out the key policy priorities for each major developing region. By shedding light on which areas of intervention will be most successful in overcoming child malnutrition in developing countries, this research will contribute to realizing the 2020 Vision of a world where hunger and malnutrition are absent." (Forward by Per Pinstrup-Andersen)Malnutrition in children Developing countries History., Malnutrition in children Developing countries Forecasting., Gender, Health and nutrition,

Testing the Underlying Chemical Principles of the Biotic Ligand Model (BLM) to Marine Copper Systems: Measuring Copper Speciation Using Fluorescence Quenching

Speciation of copper in marine systems strongly influences the ability of copper to cause toxicity. Natural organic matter (NOM) contains many binding sites which provides a protective effect on copper toxicity. The purpose of this study was to characterize copper binding with NOM using fluorescence quenching techniques. Fluorescence quenching of NOM with copper was performed on nine sea water samples. The resulting stability con- stants and binding capacities were consistent with literature values of marine NOM, show- ing strong binding with log K values from 7.64 to 10.2 and binding capacities ranging from 15 to 3110 nmole mg C −1 . Free copper concentrations estimated at total dissolved copper concentrations corresponding to previously published rotifer effect concentrations, in the same nine samples, were statistically the same as the range of free copper calculated for the effect concentration in NOM-free artificial seawater. These data confirms the applicability of fluorescence spectroscopy techniques for NOM and copper speciation characterization in sea water and demonstrates that such measured speciation is consistent with the chemical principles underlying the Biotic Ligand Model (BLM) approach for bioavailability-based metals risk assessment

Atmospheric fungal nanoparticle bursts.

Aerosol nanoparticles play an important role in the climate system by affecting cloud formation and properties, as well as in human health because of their deep reach into lungs and the circulatory system. Determining nanoparticle sources and composition is a major challenge in assessing their impacts in these areas. The sudden appearance of large numbers of atmospheric nanoparticles is commonly attributed to secondary formation from gas-phase precursors, but in many cases, the evidence for this is equivocal. We report the detection of a mode of fungal fragments with a mobility diameter of roughly 30 nm released in episodic bursts in ambient air over an agricultural area in northern Oklahoma. These events reached concentrations orders of magnitude higher than other reports of biological particles and show similarities to unclarified events reported previously in the Amazon. These particles potentially represent a large source of both cloud-forming ice nuclei and respirable allergens in a variety of ecosystems

Planar micromachined glass cantilevers utilising integrated Bragg Fabry-Perot cavities

Here we demonstrate a glass cantilever based on a unique micromachining and etching approach, combined with UV written Bragg gratings. We shall also discuss the increase in sensitivity by using two Bragg gratings to form Fabry-Pérot cavity. Cantilevers are in ultra sensitive force sensors used in applications such as Atomic Force Microscopy, mass sensing and acoustic transducers