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71.
We report on results of fabrication and optical characterisation of sub-250 nm periodic gold nanohole arrays on glass by using UV nanoimprint lithography (UV-NIL) combined with both reactive ion etching (RIE) and Cr/Au lift-off processes. The transmission spectra of the fabricated nanohole gratings were measured for different hole diameters and periods. We also show preliminary results of chemical sensing after surface modification of the gold hole arrays. In agreement with the theoretical prediction, we found that any change in the dielectric index of the surrounding environment of the metallic array produces a transmission peak red shift.  相似文献   
72.
Using a within-subject design, this study investigated the situational-specificity hypothesis, namely that alcohol outcome expectancies (AOEs), subjective evaluations of AOEs, and the speed with which AOEs are accessed from memory vary as a function of environmental setting. Thirty-nine undergraduates (20 women), of legal drinking age, responded to the Comprehensive Effects of Alcohol questionnaire (K. Fromme, E. Stroot, & D. Kaplan, 1993) that was presented on a laptop computer in 2 counterbalanced contexts: a laboratory setting and an on-campus bar. Response latencies served as dependent measures for memory accessibility. Consistent with previous research (A.-M. Wall, S. A. McKee, & R. E. Hinson, 2000), evidence in support of the situational-specificity hypothesis was found. Specifically, environmental context influenced undergraduates' expectations concerning alcohol's effects and subjective evaluations of AOEs, as well as the speed with which specific AOEs were accessed from memory. Overall, these findings suggest the need for greater attention to situational variation in AOEs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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For the design of classic computers the parallel programming concept is used to abstract HW/SW interfaces during high level specification of application software. The software is then adapted to existing multiprocessor platforms using a low level software layer that implements the programming model. Unlike classic computers, the design of heterogeneous MPSoC includes also building the processors and other kind of hardware components required to execute the software. In this case, the programming model hides both hardware and software refinements. This paper deals with parallel programming models to abstract both hardware and software interfaces in the case of heterogeneous MPSoC design. Different abstraction levels will be needed. For the long term, the use of higher level programming models will open new vistas for optimization and architecture exploration like CPU/RTOS tradeoffs.  相似文献   
76.
During tubo-ovarian high-grade serous carcinoma (HGSC) progression, tumoral cells undergo phenotypic changes in their epithelial marker profiles, which are essential for dissemination processes. Here, we set out to determine whether standard epithelial markers can predict HGSC patient prognosis. Levels of E-CADH, KRT7, KRT18, KRT19 were quantified in 18 HGSC cell lines by Western blot and in a Discovery cohort tissue microarray (TMA) (n = 101 patients) using immunofluorescence. E-CADH and KRT7 levels were subsequently analyzed in the TMA of the Canadian Ovarian Experimental Unified Resource cohort (COEUR, n = 1158 patients) and in public datasets. Epithelial marker expression was highly variable in HGSC cell lines and tissues. In the Discovery cohort, high levels of KRT7 and KRT19 were associated with an unfavorable prognosis, whereas high E-CADH expression indicated a better outcome. Expression of KRT7 and E-CADH gave a robust combination to predict overall survival (OS, p = 0.004) and progression free survival (PFS, p = 5.5 × 10−4) by Kaplan–Meier analysis. In the COEUR cohort, the E-CADH-KRT7 signature was a strong independent prognostic biomarker (OS, HR = 1.6, p = 2.9 × 10−4; PFS, HR = 1.3, p = 0.008) and predicted a poor patient response to chemotherapy (p = 1.3 × 10−4). Our results identify a combination of two epithelial markers as highly significant indicators of HGSC patient prognosis and treatment response.  相似文献   
77.
Recombinant DNA technology provides a powerful tool to create new products in many different fields. Agriculture and the agro-food industry are two of them. Genetic engineering aims at improving the yield, the nutritional quality or the technological value of food crops. The composition of foods may also be modified in order to decrease the content of toxic substances sometimes present in certain food crops. The expression of recombinant proteins in foods must be carefully assessed as proteins may induce allergic reactions in humans. Currently, the potential allergenicity of a protein can be reasonably assessed only when the protein is known to trigger an immune response in sensitive subjects. By contrast, the potential allergenicity of a protein of unknown allergenicity cannot be easily predicted as no immunoserum of allergic subjects is available. That is why an allergenicity assessment model for any genetically engineered food should be designed. Even though the gene product is completely characterised in the transgenic product, this does not necessarily provide information on its potential allergenicity. Animal models, in vitro tests and protein structure should be taken into account. Besides, allergenicity is a biosafety issue, for it deals with human health. The issue of food allergies in food safety should not be neglected, as an allergic reaction can be life threatening. ©1997 SCI  相似文献   
78.
Hot-film anemometry and an optical biprobe are used to measure local flow characteristics in the riser of an external loop airlift reactor. Important flow asymmetries are observed above the sparger and developing flow persists through a large part of the riser. As gas flow rate increases, radial gas hold-up profiles change from relatively flat to parabolic while the shape of radial liquid velocity profiles remains constant and Sauter bubble diameter increases. At large gas superficial velocities, slip velocity is found to deviate considerably from the frequently used value of 0.25 m/s. Local measurements allow a better understanding of two-phase flow in airlift reactors and can be used for CFD-modeling development and validation.  相似文献   
79.
In vivo fermentation of Ulva lactuca was studied in previously germ-free rats inoculated with human flora obtained from non-, low- and high-methane producers (groups NMP, LMP and HMP, respectively), in comparison to germ-free rats. Rats were fed either a control diet or a diet containing 4% of dried Ulva lactuca. Production of metabolites varied according to the flora and diet. Ulva lactuca induced a specific high production of methane in the HMP group. With the three human flora, Ulva diet induced a similar increase in caecal pH. In the NMP and HMP groups, this increase was associated with a fall of lactic acid caecal concentration. In the LMP group it was related to a decrease in the concentration of short-chain fatty acids. Ulva lactuca appeared to be able to regulate the β-glucuronidase and β-glucosidase activities, reducing the relatively high levels observed in groups NMP and HMP and increasing the low levels obtained in the LMP group. Results show that, although it was poorly fermented, Ulva induced significant effects on the gut microflora metabolism. The methanogenic status of the human donor appeared to be an important factor. © 1998 SCI.  相似文献   
80.
Mixed gels of gelatin and whey protein concentrate were investigated, as well as their pure systems, by tensile tests and by dynamic oscillatory measurements. The systems were studied for homogeneous particulate whey protein gels at pH 5.4 and for inhomogeneous particulate whey protein gels at pH 4.6. The influence on the systems of the Bloom number of the gelatin component has also been investigated. Results of the fracture properties, such as stress and strain at fracture, indicate a transition in rheological properties. Results of the elastic modulus, obtained by tensile measurements, as well as the storage modulus, obtained by dynamic oscillatory measurements, both agree with predictions for phase inversions from the Takayanagi models as modified by Clark, which are in agreement with the fracture properties. The transition points are different for the different mixed gel series but take place between 1 and 3 wt% gelatin and 8 wt% whey protein concentrate, depending on factors such as the microstructure of the whey protein concentrate. Dynamic oscillatory measurements showed that gel formation of whey protein concentrate is unaffected by the presence of gelatin, which is in agreement with light microscopy results. Light microscopy revealed that the mixed gel systems were bicontinuous and that the whey protein network structure was unaffected by the presence of gelatin. It is postulated that the predicted phase inversions of the mixed gels are due to a shift in rheological properties without any phase inversions in the microstructure.  相似文献   
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