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Structuration, annotation and composition are amidst the most crucial modeling issues that video editing and querying in the context of a database entail. In this paper, we propose a sequence-based, object-oriented data model that addresses them in an unified, yet orthogonal way. Thanks to this orthogonality, the interactions between these three aspects are properly captured, i.e., annotations may be attached to any level of video structuration, and all the composition operators preserve the structurations and annotations of the argument videos. We also propose to query both the structuration and the annotations of videos using an extension of ODMG's OQL which integrates a set of algebraic operators on sequences. The overall proposal is formalized and implemented on top of an object-oriented DBMS.  相似文献   
94.
The objective of this work was to describe the diversity of lactic acid bacteria in traditional raw milk Salers cheeses at the species and strain levels. The characterization of 381 strains isolated during ripening and various strain collections was investigated using physiological analysis and molecular techniques: Rep-PCR, species and genus specific amplifications and the sequence analysis of 16S rDNA for strain typing and taxonomic identification. The strains belonged to Lactobacillus plantarum, Lactobacillus paracasei, Lactococcus lactis, Lactococcus garviae, Enterococcus faecalis, Enterococcus faecium, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Streptococcus salivarius, Streptococcus millieri, Streptococcus macedonicus and Pediococcus pentosaceus. A wide phenotypic and genomic heterogeneity was observed within the different species (Lactobacillus plantarum, Lactobacillus paracasei and Leuconostoc mesenteroides) according to the origin and the time of ripening. The natural microflora was different from strain collection and each method must be combined to identify and characterize natural microflora. This study revealed the low selectivity of selective media used for the isolation of different groups of lactic acid bacteria except the Facultatively Heterofermentative lactobacilli medium selecting mesophile lactobacilli and SB medium selective for Enterococcus. The study reveals, for the first time, the microbial lactic acid bacteria community of Salers cheese and its diversity. A better knowledge of microbial flora will be useful to improve understanding of sensory quality of cheeses.  相似文献   
95.
ABSTRACT

Complexation of Pu(IV) and Th(IV) cations by the title ligands – hydrophilic sulfophenyl triazinyl derivatives of bis-triazinyl-pyridine and -bipyridine – was studied in solvent extraction systems containing a TODGA extractant and one of these hydrophilic ligands. Stoichiometries and stability constants of the complexes formed in an acidic (HNO3) aqueous phase have been determined. The Pu(IV) complexes are significantly stronger than their Th(IV) analogues. Only two complexes of each metal with SO3-Ph-BTP (1:1 and 1:2) have been detected, and only one (1:1) with SO3-Ph-BTBP; both numbers being less than expected based on the coordination numbers of the metal ions and on the denticities of the ligands. Possible reasons of this discrepancy are discussed.  相似文献   
96.
Self-assembly of regular protein surfaces around nanoparticle templates provides a new class of hybrid biomaterials with potential applications in medical imaging and in bioanalytical sensing. We report here the first example of efficiently self-assembled virus-like particles (VLPs) having a brome mosaic virus protein coat and a functionalized gold core. The present study indicates that functionalized gold particles can initiate VLP assembly by mimicking the electrostatic behavior of the nucleic acid component of the native virus. These VLP constructs are symmetric, with the protein stoichiometry and packaging properties indicating similarity to the icosahedral packing of the capsid. Moreover, a pH-induced swelling transition of the VLPs is observed, in direct analogy to the native virus.  相似文献   
97.
Cross-ply laminates made of carbon/epoxy IM7/977-2 system are investigated. The fatigue study is confined to ambient temperature conditions and zero loading ratio. Damage is characterized by the transverse crack density ρ in the central 90°-layer. The family of experimental fatigue cracking curves (ρ versus N, where N is the number of cycles, for each tensile test maximum stress amplitude) can be replaced with a set of “iso-damage curves”, i.e. contour curves of constant ρ in the σ–log (N) plane. The iso-damage curves approximately constitute a fan of straight lines that intersect at a common point (σe, log (Ns)), where Ns is a very large number of cycles beyond which no more crack appears, and σe is some fatigue limit.Our aim is to propose a simple method to predict fatigue cracking at an arbitrary maximum stress level loading by using data stemming from a constant strain rate test. This method essentially rests upon the construction of the above “iso-damage” curves, using very simple assumptions.  相似文献   
98.
BACKGROUND: Familial hypertrophic cardiomyopathy is a phenotypically and genetically heterogeneous disease. In some families, the disease is linked to the CMH2 locus on chromosome 1q3, in which the cardiac troponin T gene (TNNT2) has been identified as the disease gene. The mutations found in this gene appear to be associated with incomplete penetrance and poor prognosis. Because mutational hot spots offer unique possibilities for analysis of genotype-phenotype correlations, new missense mutations that could define such hot spots in TNNT2 were looked for in unrelated French families with familial hypertrophic cardiomyopathy. METHODS AND RESULTS: Family members were genotyped with microsatellite markers to detect linkage to the four known disease loci. In family 715, analyses showed linkage to CMH2 only. To accurately position potential mutations on TNNT2, its partial genomic organization was established. Screening for mutations was performed by single-strand conformation polymorphism analysis and sequencing. A new missense mutation, Arg102Leu, was identified in affected members of family 715 because of a G-->T transversion located in the 10th exon of the gene. Penetrance of this new mutation is complete; echocardiographic data show a wide range of hypertrophy; and there was no sudden cardiac death in this family. CONCLUSIONS: The codon 102 of the TNNT2 gene is a putative mutational hot spot in familial hypertrophic cardiomyopathy and is associated with phenotypic variability. Analysis of more pedigrees carrying mutations in this codon is necessary to better characterize the clinical and prognostic implications of TNNT2 mutations.  相似文献   
99.
The metabolites from leucine degradation play a key role in sausage aroma. Leucine catabolism is particularly important in Carnobacterium piscicola. The purpose of the study was to determine the effect of C. piscicola inoculation on the aroma of a sausage model and on leucine catabolism. Sensory analysis and implantation of Carnobacterium were performed. Aromatic compound production from (3)H leucine added to the sausage model was measured by high-performance liquid chromatography. After 18 days of ripening, the level of Carnobacterium species was 10-fold higher in sausages inoculated with C.?piscicola than in the control sausages. Addition of C.?piscicola enhanced the development of sausage aroma. The leucine was 10% more degraded in the models inoculated with C. piscicola. 3-Methyl butanoic acid was the main metabolite detected and the highest production of α-ketoisocaproic acid and hydroxy α-ketoisocaproic acid were detected in the sausage model inoculated with C. piscicola.  相似文献   
100.
The essential feature of Hypochondriasis is preoccupation with fear of having a serious disease based on a misinterpretation of bodily symptoms. While it is classified as a somatoform disorder, it presents many similarities with anxiety disorders, particularly Generalized Anxiety Disorder (GAD) which is core feature is excessive worry. Since these disorders present similar symptoms, it is also possible that similar cognitive mechanisms may be involved in their development and maintenance. The goal of the present study was to verify the relationship between illness worry and cognitive mechanisms related to GAD: Intolerance of uncertainty, faulty believes about the usefulness of worry, negative problem orientation, and cognitive avoidance. Three hundred and forty six adults (N=346) participated in this correlational study by completing relevant questionnaires. Results demonstrated that most GAD mechanisms were significant predictors of illness worry. Cognitive avoidance and negative problem orientation, entered first in the model, were the strongest predictors of the variance in illness worry scores. Faulty beliefs about worry explained only a marginal part of that variance once the first two predictors have been entered. Results also suggested that cognitive avoidance was a better predictor of illness worry compared to somatosensory-amplification, a cognitive mechanism considered as central in understanding Hypochondriasis (see Barsky & Wyshak, 1990). Clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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