2,172 research outputs found
Chemolithotrophy and physiology of bacterial nutrient limitation
An overview of the physiology of chemolithotrophic bacteria, particularly the thiobacilli, was presented. In these bacteria unique physiological traits are expressed during nutrient limited growth. Different physiological types of chemolithotrophs, pathways of sulfur oxidation, and electron transport in the thiobacilli, problems encountered by chemolithotrophs in the generation of reducing power, and some explanations of the phenomenon of obligate chemolithotrophy were considered. Mixotrophy in the thiobacilli has been studied extensively both under nutrient excess and limitation. In nature, bacteria usually grow under nutrient limitation. Yet the bulk of our knowledge of microbial metabolic function is derived from bacteria grown in laboratory batch cultures containing a great abundance of nutrients. Microbial behavior in these two types of environments can be very different, indicating the need for basing an understanding of microbial ecology on studies that rely on cultivation of microorganisms under nutrient limitation. Nutrient limited bacteria differ in several ways from those growing in large quantities of nutrients. They have different surface structures and make a much fuller use of their metabolic potential, especially by the synthesis of unique pathways of catabolic enzymes
Exceptional and Spinorial Conformal Windows
We study the conformal window of gauge theories containing fermionic matter
fields, where the gauge group is any of the exceptional groups with the
fermions transforming according to the fundamental and adjoint representations
and the orthogonal groups where the fermions transform according to a spinorial
representation. We investigate the phase diagram using a purely perturbative
four loop analysis, the all-orders beta function and the ladder approximation.Comment: 23 pages, 8 figures, 8 table
Economic viability of flexible biogas pumps in Bangladesh
This study examines the economic viability of flexible irrigation pumps that can run on biogas as well as diesel fuel in Bangladesh. Such examination faces two main hurdles. First, the ease with which farmers running flexible pumps can switch from one energy source to another is unknown and perhaps highly heterogeneous. Second, diesel prices in Bangladesh are volatile and limited information precludes direct estimation of their probability distribution. We address the first issue by evaluating the economics of flexible pumps for varying degrees of inter-fuel substitutability. To deal with the second issue, we model the probability distribution of Bangladeshi diesel prices conditional on prices in India (these markets are integrated) plus a directly estimated distribution of the error-in-prediction. Our analysis identifies conditions (patterns in diesel markets, inter-fuel substitutability, and policy) that would render flexible pumps economically attractive. Results show that flexible pumps can generate large benefits for Bangladeshi farmers
Influence of Dilution Rate on Enzymes of Intermediary Metabolism in Two Freshwater Bacteria Grown in Continuous Culture
Estimating the avoidable burden of certain modifiable risk factors in osteoporotic hip fracture using Generalized Impact Fraction (GIF) model in Iran
Backgrounds: The number of hip fractures, the most common complication of osteoporosis, has increased rapidly over the past decades. The goal of this study is to estimate the avoidable burden of certain modifiable risk factor of the condition using the Generalized Impact Fraction (GIF) model, which has been suggested and used by epidemiologists to overcome the drawbacks associated with the use of Attributable Fraction index. In addition to preventing a risk factor or the avoidable fraction of burden, this index can also calculate the change in the burden, when a risk factor is altered.Methods: International databases were searched through PubMed, CINAHLD, Embase using OVID and Google scholar. National resources were searched through IranDoc, IranMedex, SID and Journal sites. Other resources include abstract books and articles sent to the IOF congress. The following search strategy was used: (" Osteoporotic fracture" OR " Fragility Hip fracture" OR " Calcium" OR " vitamin D" OR " BMI" OR " lean body weight" OR " Physical activity" OR " exercise" OR " Smoke" ) AND (" prevalence" OR " incidence" OR " relative risk" ) and limited to " humans." Results: With regards to different scenarios already explained in modifying the studied risk factors, the greatest impact in reducing the prevalence of risk factors on osteoporotic hip fractures, was seen in low serum vitamin D levels, low physical activity and low intake of calcium and vitamin D, respectively. According to the fact that interventions for low serum vitamin D and low intake of calcium and vitamin D, are related to each other, it can be concluded that implementing interventions to change these two risk factors, in the easy, moderate and difficult scenarios, would result in approximately a 5%, 11% and 17% decrease in the burden of osteoporotic hip fractures, respectively. The addition of interventions addressing low physical activity in the easy, moderate and difficult scenarios, an 8%, 21% and 35% reduction in the burden of osteoporotic hip fractures would be reported, respectively.Conclusion: Improving serum vitamin D levels, recommending the consumption of calcium and vitamin D supplementations and advocating physical activity are the most effective interventions to reduce the risk of osteoporotic hip fractures. © 2013 Shahnazari et al; licensee BioMed Central Ltd
Influence of Vegetation Cover on Regional Evapotranspiration in Semi-Arid Watersheds in Northwest China
Customer Relationship Management Untuk Pengelolaan Donor Darah
Palang Merah Indonesia (PMI) Surabaya bergerak di pelayanan donor darah. Oleh karena itu PMI berkaitan erat dengan pelayanan kepada pendonor darah. Karena itu perlu dijaga dan ditingkatkan pelayanan kepada pendonor. Upaya yang dilakukan adalah dengan menerapkan Customer Relationship Management berbasis Teknologi Informasi.PMI menerapkan 3 siklus CRM yaitu acquitition, enhancement dan retain. Ketiga siklus tersebut diterapkan ke 3 kategori pelanggan yaitu lingkungan Perusahaan, lingkungan sekolah dan lingkungan masyarakat. Penerapan CRM mempunyai target untuk mendapatkan pendonor baru, meningkatkan pelayanan kepada pendonor dan menjaga pendonor lama untuk tetap menjadi pendonor di PMI. Sistem ini juga akan didukung dengan adanya fitur SMS gateway, sehingga informasi dapat disebar dengan cepat ke pendonor
Potential Impacts of Iron Biofortification in India
Iron deficiency is a widespread nutritional problem in developing countries, causing impaired physical activity and cognitive development, as well as maternal mortality. Although food fortification and supplementation programmes have been effective in some countries, their overall success remains limited. Biofortification, that is, breeding crops for higher micronutrient content, is a relatively new approach. We propose a methodology for ex-ante impact assessment of iron biofortification, which builds on disability-adjusted life years (DALYs) and a large household data set. Our analysis of iron-rich rice and wheat in India indicates sizeable potential health benefits. The cost-effectiveness of iron biofortification compares favourably with other interventions.biofortification, plant breeding, iron deficiency anaemia, health benefits, DALYs, cost-effectiveness, cost-benefit analysis, India, Research and Development/Tech Change/Emerging Technologies, I120, I180, I310, O150, O220, O330, Q180.,
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