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排序方式: 共有3416条查询结果,搜索用时 15 毫秒
91.
Deng Yingying Tang Fan Dong Weiming Wu Fuzhang Deussen Oliver Xu Changsheng 《Multimedia Tools and Applications》2019,78(14):19305-19323
Multimedia Tools and Applications - Selective classification (or rejection based classification) has been proved useful in many applications. In this paper we describe a selective clustering... 相似文献
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Oliver Kolb 《Journal of scientific computing》2018,74(3):1480-1503
In this paper, we introduce a third order hierarchical basis WENO interpolation, which possesses similar accuracy and stability properties as usual WENO interpolations. The main motivation for the hierarchical approach is the direct applicability on sparse grids. This is for instance of large practical interest in the numerical solution of conservation laws with uncertain data, where discontinuities in the physical domain often carry over to the (potentially high-dimensional) stochastic domain. For this, we apply the introduced hierarchical basis WENO interpolation within a non-intrusive collocation method and present first results on 2- and 3-dimensional sparse grids. 相似文献
96.
正Axel酒店坐落于马德里文学街区中心的一栋19世纪的大楼内,在西班牙黄金世纪时期,这一地区曾是一个重要的文化中心。经过岁月的洗礼,大楼至今仍保留着橙色的外墙和典雅的阳台。接手此次酒店设计的是西班牙室内设计工作室EL EQUIPO CREATIVO,设计师以西班牙著名导演佩德罗·阿莫多瓦(Pedro Almodóvar)的电影为灵感,在酒店内融入了马德里非常传统并广受欢迎的特色元素和一些著名的视觉元素。 相似文献
97.
Association of CXCR2 polymorphisms with subclinical and clinical mastitis in dairy cattle 总被引:8,自引:0,他引:8
The ability to identify objectively cows that are more or less susceptible to mastitis has been a long-standing goal. Genetic markers associated with inflammatory responses during mastitis could aid in selection of these cattle. One potential marker is CXCR2, a chemokine receptor required for neutrophil migration to infection sites, which contains single nucleotide polymorphisms (SNP) within the gene. The objective of this experiment was to evaluate the association of CXCR2 SNP genotypes with subclinical and clinical mastitis. Thirty-seven Holstein and 42 Jersey cows that completed at least 2 full lactations were used. Quarter foremilk samples were collected for bacteriological examination quarterly and when cows exhibited clinical mastitis. Subclinical mastitis was defined as the presence of the same pathogen in the same quarter in at least 2 of 3 consecutive samples. A significant association was detected between CXCR2 SNP +777 genotype and percentages of subclinical mastitis cases in Holsteins. Holsteins expressing genotype GG had decreased percentages of subclinical mastitis, but genotype CC cows had increased percentages of subclinical mastitis. Significant differences in clinical mastitis incidence were not detected between genotypes for either breed. This approach of genetically identifying mastitis resistant cows may represent an effective means of marker-assisted selection for mastitis and other inflammatory diseases involving neutrophils. 相似文献
98.
Oliver SP Almeida RA Gillespie BE Headrick SJ Dowlen HH Johnson DL Lamar KC Chester ST Moseley WM 《Journal of dairy science》2004,87(10):3322-3329
Streptococcus uberis is an important cause of mastitis in dairy cows throughout the world, particularly during the dry period, the period around calving, and during early lactation. Strategies for controlling Strep. uberis mastitis are poorly defined and are currently inadequate. Objectives of the present study were to evaluate efficacy of ceftiofur, a new broad-spectrum cephalosporin antibiotic, for treatment of experimentally induced Strep. uberis intramammary infections (IMI) in lactating dairy cows during early lactation and to determine whether extended therapy regimens enhanced efficacy of ceftiofur. Efficacy of extended ceftiofur intramammary therapy regimens was investigated in 37 mammary quarters of 23 dairy cows that developed clinical mastitis following experimental infection with Strep. uberis during early lactation. Cows that developed clinical mastitis during the challenge period were allocated randomly to 3 groups representing 3 different ceftiofur treatment regimens: 2-d (n = 7 mammary quarters), 5-d (n = 16 mammary quarters), and 8-d (n = 14 mammary quarters) treatment regimens. For all groups, 125 mg of ceftiofur hydrochloride was administered via intramammary infusion. A bacteriological cure was defined as an experimentally infected quarter that was treated and was bacteriologically negative for the presence of Strep. uberis at 7, 14, 21, and 28 d posttreatment. Percentage of Strep. uberis IMI eliminated was 43, 88, and 100% for the 2-, 5-, and 8-d ceftiofur treatment regimens, respectively. Both the 5- and 8-d ceftiofur extended therapy treatment regimens had significantly higher bacterial cure rates than the standard 2-d ceftiofur treatment regimen. The bacterial cure rate of the 8-d ceftiofur extended therapy group was marginally better (P = 0.052) than the 5-d ceftiofur extended therapy group. Results of this study indicate that ceftiofur therapy was effective for eliminating Strep. uberis experimental IMI, and 5- and 8-d extended ceftiofur therapy regimens were more effective than the standard 2-d treatment. 相似文献
99.
Comparison of brown midrib-6 and -18 forage sorghum with conventional sorghum and corn silage in diets of lactating dairy cows 总被引:2,自引:0,他引:2
Total mixed rations containing conventional forage sorghum, brown midrib (bmr)-6 forage sorghum, bmr-18 forage sorghum, or corn silage were fed to Holstein dairy cows to determine the effect on lactation, ruminal fermentation, and total tract nutrient digestion. Sixteen multiparous cows (4 ruminally fistulated; 124 d in milk) were assigned to 1 of 4 diets in a replicated Latin square design with 4-wk periods (21-d adaptation and 7 d of collection). Diets consisted of 40% test silage, 10% alfalfa silage, and 50% concentrate mix (dry basis). Acid detergent lignin concentration was reduced by 21 and 13%, respectively, for the bmr-6 and bmr-18 sorghum silages when compared with the conventional sorghum. Dry matter intake was not affected by diet. Production of 4% fat-corrected milk was greatest for cows fed bmr-6 (33.7 kg/d) and corn silage (33.3 kg/d), was least for cows fed the conventional sorghum (29.1 kg/d), and was intermediate for cows fed the bmr-18 sorghum (31.2 kg/d), which did not differ from any other diet. Total tract neutral detergent fiber (NDF) digestibility was greatest for the bmr-6 sorghum (54.4%) and corn silage (54.1%) diets and was lower for the conventional (40.8%) and bmr-18 sorghum (47.9%) diets. In situ extent of NDF digestion was greatest for the bmr-6 sorghum (76.4%) and corn silage (79.0%) diets, least for the conventional sorghum diet (70.4%), and intermediate for the bmr-18 sorghum silage diet (73.1%), which was not different from the other diets. Results of this study indicate that the bmr-6 sorghum hybrid outperformed the conventional sorghum hybrid; the bmr-18 sorghum was intermediate between conventional and bmr-6 in most cases. Additionally, the bmr-6 hybrid resulted in lactational performance equivalent to the corn hybrid used in this study. There are important compositional differences among bmr forage sorghum hybrids that need to be characterized to predict animal response accurately. 相似文献
100.
Long-term aging of copper added to soils 总被引:3,自引:0,他引:3
Ma Y Lombi E Oliver IW Nolan AL McLaughlin MJ 《Environmental science & technology》2006,40(20):6310-6317
Aging refers to the processes by which the mobility and bioavailability/toxicity of metals added to soil decline with time. Although long-term aging is a key process that needs to be considered in the risk assessment of metals in field soils, the long-term aging of Cu added to soils has not been studied in detail. In this study, the effects of aging on Cu isotopic exchangeability, total Cu in soil pore water, pore water free Cu2+ activity, and "available" Cu measured by the technique of diffusive gradient in thin film (DGT-Cu) were investigated in 19 European soils at two total Cu concentrations shown to inhibit plant (tomato) growth by 10 and 90%. After addition of Cu, the soils were leached, incubated outdoors, and sampled regularly over a 2-year period. The results showed that when water soluble Cu was added to soils, concentrations of Cu determined by each of the techniques tended to decrease rapidly initially, followed by further decreases at slow rates. Soil pH was a vital factor affecting the aging rate of Cu added to soils. The relatively low solubility products and low isotopic exchangeabilities of Cu in calcareous soils immediately after addition of soluble Cu2+ suggested Cu2+ probably precipitated in these soils as Cu2(OH)2CO3 (malachite) and Cu(OH)2. Isotopic dilution was found to be a robust technique for measuring rates of long-term aging reactions. A semi-mechanistic model was developed to describe the rate and extent of Cu aging across soils as affected by soil pH and other physicochemical parameters. Although not measured directly, it is inferred from soil physicochemical controls on Cu aging that processes of precipitation/nucleation of Cu in soils and hydrolysis of Cu2+ followed by a diffusion process controlled the decrease in Cu availability with time. The model was validated by testing it against field soils with different contamination histories and was found to successfully predict the isotopic exchangeability of Cu added to soils based on two parameters: soil pH and time. 相似文献