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61.
62.
Kriging is a linear interpolation method used by geostatisticians. In this paper we show that it can be successfully applied to image sequence coding. First we apply it to texture coding and we improve these preliminary results with an optimization method that we have named ‘inverse kriging’. Then we apply kriging and inverse kriging to motion vector fields, which are by essence smooth within an object. We show an application of these tools in the framework of the active mesh coding scheme developed within the RACE/Morpheco project.  相似文献   
63.
We report in this paper the sequence of a part of chromosome XI of Saccharomyces cerevisiae. This 17 kbp nucleotide sequence represents the right half of cosmid pUKG151 and contains nine open reading frames, YKL453, 450, 449, 448, 445, 443, 442, 441 and the 5′ part of YKL440. YKL440 was previously identified as the MBR1 gene and plays a role in mitochondrial biogenesis. YKL443 is a homologue of the yeast serine-rich protein (SRP1), while YKL453 presents strong homologies with the KIN1/KIN2/SNF1 kinase family. It must be pointed out that the size of this gene is well above average for yeast.  相似文献   
64.
Bioassays in two sympatric spider species, Tegenaria domestica and T. pagana, demonstrate that the total female chemical extract, and in particular the polar fraction, are involved in the sexual behavior of males and reproductive isolation mechanisms. In T. domestica female attractiveness was correlated with changes in 18 chemical compounds. In T. pagana little difference was observed between 12 compounds in extracts of attractive and unattractive females. 12- + 10-Methyloctacosane was not detected in attractive females of either species. Reproductive isolation was linked not only to quantitative changes in 18 chemical compounds detected in both species, but also to nine compounds present in one or the other species.  相似文献   
65.
This paper presents a global methodology for designing product for Six Sigma. First, we combine a feasibility-modeling technique with an interactive multiobjective algorithm taking into account the decision maker’s preferences (IMOP) to generate several Pareto-optimal solutions that maintain a probability of constraint satisfaction. These solutions are called reliable Pareto-optimal solutions.The solutions found by the algorithm fulfill as much as possible the decision makers’ requirements. Second, we develop a procedure for choosing a solution for implementation from among the reliable Pareto-optimal solutions generated by the algorithm. This procedure is based on the robust design and philosophy of Six Sigma. Finally, the critical characteristics are identified to help the managers develop the manufacturing system and its related control plans in order to achieve quality products. The proposed methodology is applied to vehicle crash-worthiness design optimization for side impact with structural weight and front door velocity under side impact as objectives.  相似文献   
66.
郑佩珠 《腐植酸》2013,(3):26-30
研究结果表明,土壤和其他含有腐植酸的表面,具有一种能产生还原表面物质的有机表面光化学,而这种还原表面物质可以选择性地与二氧化氮反应。亚硝酸形成的表观速率可以解释最近观察到的白天在边界层中亚硝酸高浓度现象,亚硝酸的光分解占整个羟基自由基源的60%。我们认为这种在腐植酸上的光诱导亚硝酸产物对最低对流层的化学过程有潜在的重要影响。  相似文献   
67.
Despite the availability of X-ray crystal structure data for several members of the G-protein-coupled receptor (GPCR) superfamily, structure-based discovery of GPCR ligands has been exclusively restricted to class A (rhodopsin-like) receptors. Herein we report the identification, by a docking-based virtual screening approach, of noncompetitive ligands for two related class B (secretin-like) GPCRs: the glucagon receptor (GLR) and the glucagon-like peptide 1 receptor (GLP-1R). Starting from a knowledge-based three-dimensional model of the GLR, a database of 1.9 million commercially available drug-like compounds was screened for chemical similarity to existing GLR noncompetitive antagonists and docked to the transmembrane cavity of the GLR; 23 compounds were then selected based on protein-ligand interaction fingerprints, and were then purchased and evaluated for in vitro binding to GLR and modulation of glucagon-induced cAMP release. Two of the 23 compounds inhibited the effect of glucagon in a dose-dependent manner, with one inhibitor exhibiting the same potency as L-168 049, a reference noncompetitive GLR antagonist, in a whole-cell-based functional assay. Interestingly, one virtual hit that was inactive at the GLR was shown to bind to GLP-1R and potentiate the response to the endogenous GLP-1 ligand.  相似文献   
68.
Resistance to puncture or cutting by pointed blades is an important property of elastomer membranes and glove materials, making it necessary to define a fundamental criterion for measuring this resistance. However, the intrinsic properties controlling puncture/cutting crack propagation are still unidentified. This study has established a simple criterion describing the relationship between true fracture energy and the puncture/cutting process. Several samples of neoprene and nitrile rubber materials 1.6 mm and 3.2‐mm thick were tested using three pointed blades having tip angles of 22.5°, 35°, and 56°. It was found that both friction energy and true fracture energy contributed to global applied energy. True fracture energy, which is useful for in‐depth study of the puncture/cutting process, was independent of material thickness, blade geometry, and blade lubrication. Furthermore, friction energy was approximately twice as great as true fracture energy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44945.  相似文献   
69.
Enhanced cellular DNA repair efficiency and suppression of genomic instability have been proposed as mechanisms underlying radio-adaptive responses following low-dose radiation exposures. We previously showed that low-dose γ irradiation does not generate radio-adaptation by lowering radiation-induced cytogenetic damage in mouse spleen. Since radiation may exert tissue-specific effects, we extended these results here by examining the effects of γ radiation on cytogenetic damage and proliferative index in bone marrow erythrocytes of C57BL/6 and BALB/c mice. In C57BL/6 mice, the induction of micronuclei in polychromatic erythrocytes (MN-PCE) was observed at radiation doses of 100 mGy and greater, and suppression of erythroblast maturation occurred at doses of >500 mGy. A linear dose–response relationship for MN-PCE frequencies in C57BL/6 mice was established for radiation doses between 100 mGy and 1 Gy, with departure from linearity at doses of >1 Gy. BALB/c mice exhibited increased MN-PCE frequencies above baseline following a 20 mGy radiation exposure but did not exhibit radio-sensitivity relative to C57BL/6 mice following 2 Gy exposure. Radio-adaptation of bone marrow erythrocytes was not observed in either strain of mice exposed to low-dose priming γ irradiation (single doses of 20 mGy or 100 mGy or multiple 20 mGy doses) administered at various times prior to acute 2 Gy irradiation, confirming the lack of radio-adaptive response for induction of cytogenetic damage or suppression or erythrocyte proliferation/maturation in bone marrow of these mouse strains.  相似文献   
70.
This article outlines the processes undertaken to revise Canada's Food Guide and shares the updated science that underpins the dietary pattern. The Dietary Reference Intakes provide updated nutrient requirement values and better tools for dietary assessment and planning. Alignment with this updated science was an important component of defining and communicating accurate dietary guidance for Canada. Ensuring that stakeholders had access to the updated review of requirements led to the development of the text Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Equally important was ensuring that stakeholders were provided opportunity to influence the approach taken to giving dietary guidance, both content and the elements of the final package. A combination of research, consultation and expert advice guided the process to the release of Eating Well with Canada's Food Guide (2007).  相似文献   
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