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81.
During a screening of Salmonella enterica in foods of animal origin four isolates of serovar Typhimurium carrying hybrid virulence-resistance plasmids were detected. Three of them, one from pork and two from chicken meat, contained pUO-StVR2, a derivative of the pSLT virulence plasmid with the blaOXA-1, catA1, aadA1, sulI and tet(B) genes, which confer resistance to ampicillin, chloramphenicol, streptomycin-spectinomycin, sulfonamides and tetracycline, respectively. The fourth isolate, from pork, harbored a pUO-StVR2 variant (termed ν8) with an additional dfrA10 gene responsible for resistance to trimethoprim. This gene is part of the orf513-dfrA10-qacEΔ1-sul1 element characteristically found in complex class 1 integrons. Pulsed-field gel electrophoresis identified two XbaI-BlnI combined profiles: X2-B2 generated from the three pUO-StVR2 isolates, and X12-B17 shown by the pUO-StVR2-ν8 isolate. The same profiles have also been found in clinical and ill pig isolates, supporting chicken and pork meat as vehicles for transmission of Typhimurium carrying pUO-StVR2-like plasmids.  相似文献   
82.
A new approach to manufacture a complete thermal barrier coating system in a single step is studied in the frame of the European FP7 project PARTICOAT. Spherical μm-Al particles are deposited on different substrate alloys. During the sintering process in air, the μm-Al particles are oxidized and converted into hollow alumina spheres forming a ceramic “foam” (top coat), and simultaneously an Al rich diffusion layer (bond coat) is formed in the subsurface zone of the substrate.The “green” coatings deposited by air brush on IN738, René80 and CM247 nickel based alloys were cured at 300 °C and then isothermally exposed at 800 and 1000 °C in air for up to 1000 h. The oxide formation and the microstructure of the coatings were studied by thermo gravimetrical analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM-EDX).The coatings were adherent for all the substrates and temperatures tested. René80 shows the lowest mass gain whereas IN738 and CM247 show higher mass gains at the temperatures studied. Additionally, the use of reactive element oxides in the coating was investigated, demonstrating the flexibility and viability of this low cost coating concept.  相似文献   
83.
In the literature one can find different accuracy measures that are built from the error matrix. However, standard accuracy assessment, which is based on the error matrix, is incomplete when dealing with fuzzy sets or when errors do not have the same importance. In this paper, we propose an extension of the error concept for soft (or crisp) classification that will be able to extend standard accuracy measures (e.g., overall, producer's, user's or Kappa statistic) that can be used in any framework: errors with different importance, soft classifier and crisp reference data (expert) or with a fuzzy expert. In particular, a weighted measure is built that takes into account the preferences of the decision maker in order to differentiate some errors that must not be considered equal.  相似文献   
84.
Caseinmacropeptide (CMP) is a C‐terminal glycopeptide released from κ‐casein by the action of chymosin during cheese‐making. It is recognised as a bioactive peptide and is thought to be an ingredient with a potential use in functional foods. CMP occurs in sweet cheese whey and whey protein concentrate (WPC). Its composition is variable and depends on the particular whey source and the fractionation technology employed in the isolation. There were no significant (P < 0.05) differences in the relative apparent viscosities between species of CMPs (cow, ewe and goat). Analyses at different pH (2, 4, 7, 10), ionic strength (0, 0.2, 0.4 and 0.7 as NaCl molarity) and protein concentration (50, 100 and 200 g kg?1) at temperatures from 10 to 90 °C carried out found pH 7 and high protein concentration (200 g kg?1) conditions to be the best for CMP solutions to keep low and constant relative viscosity values with increasing temperature up to 75 °C. The viscoelastic properties–storage modulus, loss modulus and phase angle–of the different CMPs and WPC solutions were determined. Heat‐induced rheological changes in CMP solutions occurred at moderate temperatures (40–50 °C) with no appreciable differences in viscosity. Gelation took place significantly (P < 0.05) earlier in goat CMP (41 °C), followed by cow CMP (44 °C), ewe CMP (47 °C) and WPC (56 °C). Heating at 90 °C showed that WPC required significantly (P < 0.05) longer times to form gels (>5 min) than the CMPs (<5 min). WPC gels had higher (>20°) phase angle than CMP (<20°), which could be associated with untidy structures, limiting elastic properties of the gel. Copyright © 2006 Society of Chemical Industry  相似文献   
85.
Algebras difusas     
Resumen En este trabajo se propone una estructura de álgebra difusa (borrosa) basada en la distinción entre difusidad extensiva y comprehensiva, desarrollando y conectando los trabajos de Nahmias sobre variables difusas, de Klement sobre medibilidad difusa y de Nowakowska sobre estructuras de conceptos.   相似文献   
86.
A phage-displayed combinatorial peptide library was used to define the specificity of one of the three Src homology 3 (SH3) domains in a novel cytoskeletal protein, named CAP, for Cbl Associated Protein. The C-terminal SH3 domain was used to affinity select peptides with the consensus, PXPPXRXSSL, from a library of X6PXXPX6 peptides. Peptide sequences resembling this consensus were identified in two signal transduction proteins, c-Cbl and son-on-sevenless (Sos), previously shown to interact with the C-terminal SH3 domain of CAP. Genetic fusion of 16 and 14 amino acid segments of c-Cbl and Sos, respectively, to bacterial alkaline phosphatase confirmed that these segments were potential ligand sites for the C-terminal SH3 domain of CAP. Alanine-scanning mutagenesis of the c-Cbl peptide ligand confirmed that most of the residues, which were conserved among the peptide ligands selected from the combinatorial peptide library, contributed to binding to the C-terminal SH3 domain of CAP.  相似文献   
87.
The regioselectivity of enzymatic transgalactosidation depends on the source of the beta-galactosidase used. When the galactosyl acceptor only contains secondary hydroxyl groups, e.g., D- or L-xylose, it is possible to find an enzyme that catalyses preferentially the synthesis of any of the three regioisomers 4-, 3- and 2-O-beta-D-galactopyranosyl-D-xylose (1, 2 and 3, respectively) or 4-, 3- and 2-O-beta-D-galactopyranosyl-L-xylose (4, 5 and 6, respectively). Enriched mixtures in 1, 2 or 3 were obtained using beta-galactosidases from Escherichia coli, bovine testes or Aspergillus oryzae, respectively, by transgalactosidation reaction of O-nitrophenyl-beta-D-galactopyranoside and D-xylose, and enriched mixtures in 4, 5 or 6 were obtained in a similar way using beta-galactosidases from Aspergillus oryzae, lamb small-intestine (intestinal lactase-phloridzin hydrolase) or Saccharomyces fragilis, respectively, using L-xylose as acceptor.  相似文献   
88.
We have reported previously that the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMLP) inhibits transiently Ca2+ entry through the plasma membrane Ca2+ pathway activated by emptying the intracellular Ca2+ stores (Montero, M., García-Sancho, J., and Alvarez, J. (1993) J. Biol. Chem. 268, 13055-13061). We show here that calyculin A and okadaic acid, inhibitors of protein phosphatases 1 and 2A, prevent the spontaneous reversion of the fMLP-induced inhibition of the entry of Ca2+ and Mn2+ (used as a Ca2+ surrogate), leading to a permanently inhibited Ca2+ entry pathway. At high concentrations or long incubation times the phosphatase inhibitors were even able to inhibit the store-operated Ca2+ entry pathway (SOCP) in the absence of fMLP. Inhibition of SOCP by phorbol dibutyrate, which is not reversible, was not modified by phosphatase inhibitors. These results provide additional support for the view that fMLP inhibits SOCP through phosphorylation of either the SOCP protein or a regulatory protein and indicate that dephosphorylation mediated by protein phosphatases 1 and/or 2A restores the activity of SOCP after inhibition by fMLP. The time course of the inhibition of SOCP by fMLP was similar to the one reported previously for the transient fMLP-induced phosphorylation of a 47-kDa protein involved in the generation of respiratory burst, which was similarly affected by the phosphatase inhibitors.  相似文献   
89.
In the study described here, supported planar bilayers (SPBs) of 1-palmitoy-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE):cardiolipin (CL) (0.8:0.2, mol/mol) were examined using atomic force microscopy (AFM). SPBs were formed from suspensions of POPE:CL (0.8:0.2, mol/mol) in inverted hexagonal (H(II)) phases (buffer containing Ca(2+)). Three laterally segregated domains which differ in height were observed at 24 degrees C. Based on the area accounted for each domain and the nominal composition of the mixture, we interpret that the higher domain is formed by CL, while the intermediate and lower domains (LDs) are formed by POPE. The three domains respond to temperature increase with relative changes in their area. At 37 degrees C, we observed that the increase in the area of the intermediate domain occurs at the expense of the LD. (31)P-nuclear magnetic resonance ((31)P-NMR) and Differential scanning calorimetry (DSC) were used in combination with AFM to characterize the phase behavior of the suspensions and to elucidate the nature of the structures observed.  相似文献   
90.
Photonic Network Communications - Network Slicing appears as one of the enabling technologies for 5G networks to accommodate services with different requirements and availability. The present work...  相似文献   
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