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81.
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   
82.
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   
83.
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   
84.
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   
85.
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   
86.
Recent evidence indicates that reactivation of consolidated memories returns them to a protein-synthesis-dependent state called reconsolidation. The hypothesis that memories reconsolidate has never been assessed in social memory. The authors tested whether sheep (Ovis aries) mothers' memory of their lambs undergoes reconsolidation upon reactivation. After 7 days of mother-young contact, ewes were separated from their lambs for 8 hr, after which the lambs were reintroduced to their mothers for a 10-min reactivation session. Before reactivation, mothers received a subcutaneous injection of either the protein-synthesis inhibitor cycloheximide (CY, 1 mg/kg) or vehicle. Mothers' lamb memory was tested 1 hr (short-term memory [STM]) or 16 hr (long-term memory [LTM]) after reactivation. Mothers treated with CY exhibited intact STM but deficient LTM. CY injection without reactivation or before presentation of an alien lamb induced no deficit in LTM. CY-induced LTM deficit was alleviated by (a) introducing a reminder just before the LTM test, (b) extending mother-young contact, and (c) preventing suckling by the familiar lamb during reactivation. Thus, reconsolidation can be shown to exist in social memory, and some of its boundary conditions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
88.
The perception of texture has been correlated to the microstructure of particulate whey protein gels. A full, two-level, factorial experimental design was used in which the processing conditions, pH, heating rate and addition of salt were used as design factors. The texture of the gels was analysed by a sensory panel, and the microstructure was analysed by light and electron microscopy. The microstructure was quantified by using different types of image analysis.

In this study of particulate whey protein gels, the test principles of analysing texture were divided into two groups: destructive tests and non-destructive tests. The microstructural parameters can also be divided into two groups: overall network dimensions (pore size and particle size) and strand characteristics. The texture as measured with destructive methods was sensitive to overall network dimensions, whereas texture as measured with non-destructive methods was sensitive to the strand characteristics of particulate protein gels.  相似文献   

89.
This study was designed to establish whether phonological working memory skills could be assessed in children below 4 yrs of age. A group of 2- and 3-yr-old children were tested on 3 phonological memory measures (digit span, nonword repetition, and word repetition) and were also given tasks that tapped other cognitive skills. Scores on the 3 phonological memory tasks were closely related. In addition, repetition performance was linked with both vocabulary knowledge and articulation rate. Results indicate that phonological memory skills can be reliably assessed in very young children by using conventional serial span and repetition procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
Two series of water-soluble dendritic catanionic assemblies, acting as multisite analogues of galactosylceramide (Galbeta1cer), have been prepared with the goal of blocking HIV infection prior to the entry of the virus into human cells. Trifunctional and hexafunctional cinnamic acid-terminated dendrimers have been synthesized from phosphorus-containing dendrimers bearing aldehyde end groups. A classical acid-base reaction performed in water between acid-terminated dendrimers and stoichiometric amounts of N-hexadecylamino-1-deoxylactitol provided the expected catanionic assemblies. Antiviral assays on these supramolecular entities confirmed the crucial roles both of multivalency effects and of lipophilicity on the biological activity of Galbeta1cer analogues. Moreover, correlation between in vitro tests and molecular modeling highlights the specific influence of the assembly shape on the anti-HIV efficiency, with the tri- and hexafunctional cored dendrimers, both decorated with 12 sugar moieties, exhibiting IC50 values of 1.1 and 0.12 microM, respectively.  相似文献   
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