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In present work, we investigate numerical simulation of steady natural convection flow in the presence of weak magnetic Prandtl number and strong magnetic field by involving algebraic decay in mainstream velocity. Before passing to the numerical simulation, we formulate the set of boundary layer equations with the inclusion of the effects of algebraic decay velocity, aligned magnetic field and buoyant body force in the momentum equation. Later, finite difference method with primitive variable formulation is employed in the physical domain to compute the numerical solutions of the flow field. Graphical results for the velocity, temperature and transverse component of magnetic field as well as surface friction, rate of heat transfer and current density are presented and discussed. It is pertinent to mention that the simulation is performed for different values of algebraic decay parameter α, Prandtl number Pr, magnetic Prandtl number Pm and magnetic force parameter S.
Properties of dust-ion-acoustic shock waves (DIASWs) in an unmagnetized dusty plasma (containing inertial ions, Maxwellian electrons with two distinctive temperatures and negatively charged immobile dust) are investigated. The hydrodynamic equation for inertial ions has been used to derive the Burgers equation. The effects of two-electron-temperature and ion kinematic viscosity, which are found to significantly modify the basic features of the DIASWs, are discussed.
The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of ‘optimal’ concentration of serum 25(OH)D needs to define ‘optimal’ with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.
Heterogeneous catalysts that accelerate the photolytic destruction of organic contaminants in water are a potentially inexpensive and highly effective way to remove both trace-level and saturated harmful compounds from industrial waste streams and drinking water. Porous photocatalytic materials can have the combined qualities of high surface area and relatively large particle sizes, as compared with nanoparticulate catalyst powders like titanium dioxide . The larger particle sizes of the porous materials facilitate catalyst removal from a solution, after purification has taken place.
We have synthesized new kinds of photocatalytic porous oxide materials that can be used to purify contaminated water by accelerating the photodegradation of any kind of organic pollutant. The new materials have very large open pore structures that facilitate the diffusion, the surface contact of contaminants, and solvent flow through the catalyst. These qualities enhance surface reactions important to the process. The new catalysts have shown robust physical and chemical properties that make them candidates for real applications in polluted water decontamination.
This paper explores a number of socioeconomic factors thought to explain the wide prevalence of undernutrition among rural Bangladeshi women. The 1992 baseline survey data of the BRAC-ICDDR,B Joint Research Project at Matlab were used. Anthropometry was performed on a random sub-sample of 1462 currently married, non-pregnant women between 15 and 49 years of age. Women's nutritional status was defined in terms of Body Mass Index (BMI=wt in kg/ht in m2). Compared with women from better-off households, the mean weight (41.2 vs 43.0 kg; p<0.0001), mid-upper arm circumference (MUAC) (22.1 vs 22.7; p<0.0001), and BMI (18.5 vs 19.1; p<0.0001) of poor women were consistently lower. However, no significant difference in mean height was found between the two groups. The results showed that women aged more than 35 years are twice as likely to have a BMI<18.5 compared with younger women. Both years of schooling received and socioeconomic status are found to be important predictors of women's BMI. Women who have received one or more years of formal education are nearly half as likely to suffer chronic energy deficiency (BMI<18.5) than women with no schooling. Again, better-off women are found to be 0.77 times less likely to have chronic energy deficiency than women from poor households. The implications of these findings in improving the nutritional status of rural Bangladeshi women are discussed.
The purpose of this paper was to quantify economic and energy use implications of new improved irrigation and limited tillage production systems for the Texas High Plains. Per hectare uses of natural gas and electricity under alternative irrigation distribution systems for corn, sorghum, wheat, cotton, and soybeans were utilized to estimate total amounts of natural gas and electricity used in the production of these crops on the High Plains of Texas. The amount of diesel fuel used was estimated for conventional and limited tillage systems under dryland and irrigation production. Total amounts of water used for the five crops under the improved and conventional irrigation systems were also estimated for the High Plains. Results indicated improved irrigation and limited tillage systems reduced energy and water use on the High Plains. Total natural gas and electricity were estimated to decline over 20 percent, diesel fuel declined 32 percent, and water use for irrigation declined about 23 percent. Use of the improved irrigation and limited tillage production systems was also shown to significantly increase annual net returns to farmers ($40.0 million or 13.3 percent).
This study evaluated implications of increased bollworm problems in a 20-county area of the Texas High Plains relative to cotton yields and economic impact. Results did not indicate a serious effect of bollworms upon lint yield when insecticides were used for control. However, estimated annual reduction in farmer profit due to the bollworm for 1979-81 was over $30 million. Yields were estimated to decline about 300,000 bales without insecticide use and about 30,000 bales with insecticide use. This decline suggests potentially serious implications for the comparative economic position of cotton in this region if insecticide resistance were to develop among insect pests.
A long-season (160–180 days) cotton variety with a conventional production system was formerly grown in the Texas Coastal Bend Region. Cotton producers in the region used intensive insecticide applications throughout the growing season and harvested in August or September, and occasionally in October. In general, intensive insecticide applications for boll weevil and fleahopper control destroyed the beneficial insects and spiders. Late-season tobacco budworm infestations were thereby aggravated. These late-season insect infestations were a result of the relatively high rainfall during August and September. Moreover, high rainfall during this time not only interfered with harvest, but also reduced both the yield and quality of cotton (Lacewell et al.).