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171.
Bovine respiratory disease (BRD) is a multifactorial disorder responsible for severe economic losses in dairy and feedlot herds. Advances in next-generation sequencing mean that microbial communities in clinical samples, including non-culturable bacteria, can be characterized. Our aim was to evaluate the microbiota of the upper respiratory tract of healthy calves and calves with BRD using whole-genome sequencing (shotgun metagenomics). We performed deep nasopharyngeal swabs on 16 Holstein heifer calves (10 healthy and 6 diagnosed with BRD during the study) at 14 and 28 d of life in 1 dairy herd near Ithaca, New York. Total DNA was extracted, and whole-genome sequencing was performed using the MiSeq Illumina platform (Illumina Inc., San Diego, CA). Samples included 5 predominant phyla: Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Tenericutes. At the genus level, we observed differences between groups for Pseudomonas spp. At the species level, Mannheimia haemolytica was the most abundant bacterium detected. We detected significant differences between groups of calves in the relative abundance of Pseudomonas fluorescens. Pasteurella multocida was among the 20 most abundant species, and Moraxella catarrhalis, commonly associated with pneumonia in humans, was detected in all groups. Analysis of resistance to antibiotics and compounds profiling revealed differences in cobalt-zinc-cadmium resistance. Further research to elucidate the role of Moraxella catarrhalis in BRD is warranted. Genes that were resistant to cobalt-zinc-cadmium, observed mostly in calves with BRD, might be associated with difficulties in antibiotic treatment.  相似文献   
172.
Households in rural Kenya are sensitive to weather shocks through their reliance on rain-fed agriculture and livestock. Yet the extent of vulnerability is poorly understood, particularly in reference to extreme weather. This paper uses temporally and spatially disaggregated weather data and three waves of household panel survey data to understand the impact of weather extremes –including periods of high and low rainfall, heat, and wind– on household welfare. Particular attention is paid to heterogeneous effects across agro-ecological regions. We find that all types of extreme weather affect household well-being, although effects sometimes differ for income and calorie estimates. Periods of drought are the most consistently negative weather shock across various regions. An examination of the channels through which weather affects welfare reveals that drought conditions reduce income from both on- and off-farm sources, though households compensate for diminished on-farm production with food purchases. The paper further explores the household and community characteristics that mitigate the adverse effects of drought. In particular, access to credit and a more diverse income base seem to render a household more resilient.  相似文献   
173.
The aim of this work was to analyse the influence of defatted almond flour on soya bean‐based gluten‐free pasta. Optimal cooking time of pasta varied between 2.0 and 3.5 min, while cooking loss ranged 6.1% and 19.7%. The total protein content of samples varied from 30.4% to 41.0% (dry basis, db) in cooked pasta. The total phenols content of cooked samples varied between 1.66 and 2.99 mg ellagic acid equivalent/g, while the antioxidant activity (DPPH?) ranged between 19.1% and 41.9%. The sensory test showed no significant differences between the formulated pasta samples among brightness (3.20–3.27), surface appearance (1.14–1.20), hardness (2.14–2.36) and elasticity (1.56–1.71). Pasta developed is an innovative product that improves nutritional and functional properties of gluten‐free pasta compared to gluten‐free and traditional wheat flour pasta available on market.  相似文献   
174.
175.
首先分析了电信运营商内部业务运营支撑系统亟需解决的安全问题,围绕建立健全IT安全保障体系建设目标,设计了基于能力成熟度的安全能力评价模型,并给出了模型实现的安全基线达标体系标准实践的具体标准和方案。  相似文献   
176.
Poly(hydroxybutyrate‐co‐valerate) (PHBV), a biodegradable polymer produced from a renewable microbiological source, was reinforced with varying amounts of curauá fibers (CFs). The composites were produced using a twin‐screw extrusion and injection process. Scanning electron microscopy showed poor adhesion between the matrix and fiber; however, mechanical testing showed that the addition of the fiber improved the mechanical properties. Composites with 20 and 30 wt% CF displayed the best properties; however, because of the difficulties in processing composites with a CF content of 30 wt%, it was concluded that the ideal content of CF was 20 wt%. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers  相似文献   
177.
Lignans and phytoestrogens have been associated with protective effect against hormone‐related diseases, for example, cancer of the breast and prostate, and potential mechanisms for this effect have been reported. Antioxidants also appear to have some protective effect against diseases associated with reactive free radicals such as coronary heart disease and cancer. Whole grains contain some of these substances particularly the mammalian lignan precursors, vitamin E, other phenolic compounds, Se, and phytic acid. These substances may in part be responsible for the reduced risk of cancer and coronary heart disease associated with intake of high‐fiber diets containing whole grains. Because they are more associated with the fiber in the outer layers of the grain, the intake of whole vs. refined grain is emphasized for optimum health benefits.  相似文献   
178.
In recent years a schism has become apparent in artificial intelligence and law between those who claim that legal expert systems cannot be built without first establishing a satisfactory theoretical model of law ("purists") and those whose main desire is to build working systems with or without theoretical underpinning ("pragmatists"). Most attempts at finding a jurisprudential model for building expert systems, however, have inconclusively attempted to apply traditional “grand theories” and have embedded themselves in the long standing controversies of analytical jurisprudence. This paper highlights other theoretical possibilities for modelling law which have been sidelined in the AI and law field. In particular, it promotes the adoption of a feminist theoretical perspective on law and legal knowledge representation. Feminist legal critique has a discrete, concrete and pragmatic approach and so may be a good tool for the resolution of the demands of both purists and pragmatists. The paper applies these insights to a proposed child custody expert system.  相似文献   
179.
Although genetic and protein manipulations have been the cornerstone for the study and understanding of biological processes for many decades, complimentary nanoscale observations have only more recently been achieved in the live-imaging mode. It is at the nano measurement level that events such as protein-protein interactions, enzymatic conversions, and single-molecule stochastic behavior take place. Therefore, nanoscale observations allow us to reinterpret knowledge from large-scale or bulk techniques and gain new insight into molecular events that has cellular, tissue, and organismal phenotypic manifestations. This review identifies pertinent questions relating to the sensing and directional component of cancer cell chemotaxis and discusses the platforms that provide insight into the molecular events related to cell motility. The study of cell motility at the molecular imaging level often necessitates the use of devices such as microinjection, microfluidics, in vivo/intravital and in vitro chemotaxis assays, as well as fluorescence methods like uncaging and FRET. The micro- and nanofabricated devices that facilitate these techniques and their incorporation to specialized microscopes such as the multiphoton, AFM, and TIR-FM, for high-resolution imaging comprise the nanoplatforms used to explore the mechanisms of carcinogenesis. In real-time observations, within a milieu of physiological protein concentrations, true states of dynamic and kinetic fluxes can be monitored.  相似文献   
180.
Because of the spreading of nonlinear microscopies in biology, there is a strong demand for specifically engineered probes in these applications. Herein, we report on the imaging properties in living cells and nude mice brains of recently developed water soluble blue fluorophores that show efficient diffusion through cell membranes and blood-brain barriers. They are characterized by two-photon absorption cross-sections of 100-150 Goeppert-Mayer range in the near IR and fluorescence efficiencies of up to 72% in water. They were found to stain homogeneously the cytoplasm of cultured living cells within minutes. Moreover, their diffusion times and fluorescence characteristics in the cytoplasm suggest a hydrophobic association with intracellular membranes. Their intracellular fluorescent decays were found to be almost mono-exponential, a very favorable feature for fluorescence lifetime imaging. Two photon images of living cells were obtained with a good signal to noise ratio using laser powers in the sub-milliwatt range. This allows continuous imaging without significant photobleaching for tens of minutes. In addition, these fluorophores allowed in vivo three-dimensional two-photon imaging of mice cortex vasculatures and extra vasculature structures, with no sign of toxicity.  相似文献   
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