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Global demand for wood fuel energy is high and rising due to population increases, particularly in sub-Saharan Africa, where firewood and charcoal are the main sources of cooking energy. Inefficient cooking techniques consume large amounts of fuel and create indoor pollution, with negative health impacts particularly among women and small children. Efficient cooking stoves can potentially save fuel and reduce the health risks of smoke in the kitchen. This study compared the ease of use, energy consumption, fuel use efficiency and gas and particle emissions of a small-scale gasifier cooking stove with that of a traditional three-stone stove and an improved Hifadhi stove in a smallholder farming setting in Kenya. This was done by participatory evaluation of these cooking techniques by women on smallholder farms, assessing fuel consumption, time used in cooking and indoor air concentrations of carbon monoxide and fine particulate matter. It was found that compared with traditional and improved cooking stoves, the gasifier domestic cooking system saved 27–40% of fuel, reduced cooking time by 19–23% and reduced emissions by 40–90%. Thus the gasifier system has potential to alleviate energy and time poverty among small-scale farmers, while improving kitchen air quality. These new findings can assist in development of cleaner biomass cooking technologies in developing countries. Women who cooked using the gasifier preferred it to current cooking practices due to perceived benefits. Thus the gasifier is appropriate for rural areas; it constitutes a cleaner cooking system that saves fuel, produces charcoal for another round of cooking, cooks rapidly, and reduces indoor air pollution from cooking with biomass fuel. However, there is a need to improve the design to make it more stable and safer. [ABSTRACT FROM AUTHOR]

Oxygen content and interface properties in SrTiO/sub 3//YBa/sub 2/Cu/sub 3/O/sub 7-x/(STO/YBCO) bi-layer definitely affect electric properties of superconducting field effect transistor (SuFET). Good interface can be obtained by molecular beam epitaxy (MBE). Deposition pressure of MBE is too low to oxygenate the ultra-thin YBCO through STO. The oxygen pressure of pulsed laser deposition (PLD) is high enough to oxygenate the YBCO but YBCO film surface is degraded by impurity gases because of its high oxygen pressure. We successfully combined MBE and PLD methods to obtain STO/YBCO bilayers with both good interface and electrical properties. The transconductance of SuFET was 5mS/cm, which is higher than SuFET grown by all-MBE and all-PLD. [ABSTRACT FROM PUBLISHER]

In Rwanda, nutritional problems are increasingly drawing attention, and the National Nutrition Policy focuses on the solutions to reduce the prevalence of malnutrition and to improve household food intake. Since rural Rwandans typically have meals at home and household food intake is known to be affected by their socioeconomic status (SES), care should be taken to ensure that homemade meals are healthy. This study aimed to assess the current nutrient content of porridge and mixture so as to recommend modifications to be made to improve nutrient intake within rural households in Rwanda. A crosssectional study was conducted; anthropometric measurements and one-day weighed food records (WFRs) were collected from 30 participants in four households with different SES in the Musanze district in the Northern Province of Rwanda. The first objective of this study was to compare nutritional status and food intake among households with different SES. The study results indicated that SES did not solely explain the nutritional status of the household members, and co-existence of over-nutrition and undernutrition was observed within the better-off household. Although meal frequency per day and the number of dishes and ingredients were positively related to household SES, rural Rwandans consumed monotonous diets characterized by porridge for breakfast and mixture (a dish boiled some foods together) for lunch and dinner as a whole. These two familiar dishes, porridge and mixture, greatly affected their energy and nutrient intakes. The second objective was to compare energy and nutrient contents in the same dishes with different ingredients and cooking methods. Porridges were made by dissolving mixed flour (maize and sorghum flours) in hot water. The porridge did not contain vitamin A. The energy, protein, and iron contents of the porridge were affected by flour concentration. Thick porridge whose flour concentration is 13% is recommended. Beans and potatoes were popular ingredients of mixture. Beans were major sources of energy, protein, and iron intakes. Contrary to general assumption, roots and tubers were also the major sources of protein and iron intakes among the participants. To cook mixture that is well boiled and contains beans and potatoes is a feasible way to increase energy and nutrient intakes regardless of household SES. In order to provide good vitamin A intake, addition of yellow plantain, palm oil, and/or tomato is recommended. This study presents locally and economically feasible recommendations to make popular dishes more nutritious for rural Rwandans. [ABSTRACT FROM AUTHOR]

Examines the use of a low-energy ion scattering spectroscopy (ISS) in analyzing the atomic structure of c-axis oriented YBa[sbu 2]Cu[sub 3]O[sub 7] thin films. Effects of carbon dioxide and atmospheric water on superconducting oxides; Comparison between ISS and low energy ion diffraction; Ratio of yttrium to barium.

A noncontact cryogenic microwave measurement system has been developed for the characterization of passive and active superconducting devices by means of an unloaded quality factor measurement technique. The measurement system was designed specifically for the characterization of planar thin film resonant structures as a function of temperature (4-300 K), frequency (100 MHz-26.5 GHz), and dc voltage bias (≤100 V). It has been used for basic device studies of novel active superconducting lumped components made of metal-oxide superconductor/ insulator heterostructures. [ABSTRACT FROM AUTHOR]

Examines the deposition of YBa[sub 2]Cu[sub 3]O[sub 7-x] thin films by an ozone-assisted reactive coevaporation technique. Use of low-energy electron diffraction and ion scattering spectroscopy; Surface characteristics of the material; Factors for keeping a clean outermost surface.