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31.
Juan R. Gonzlez-Velasco Miguel A. Gutirrez-Ortiz Jean-Louis Marc M. Pilar Gonzlez-Marcos Gilbert Blanchard 《Applied catalysis. B, Environmental》2001,33(4):452-314
A number of experiments were carried out with fresh and aged high surface area Ce0.68Zr0.32O2 mixed oxide samples with complex feed-streams in order to determine their performance as three way catalyst (TWC). The results confirmed the oxygen storage capacity (OSC) of these samples, which favour NO conversion in cycled versus stationary stoichiometric operation. Several experiments carried out with different feed-streams have shown that a pre-reducing treatment can significantly improve both NO reduction at low-temperature and selectivity to N2, which can be very useful to reduce the emission of nitrogen oxides immediately after starting the automobile. Although a significant reduction of the specific surface area of the mixed oxide takes place during ageing at 1173 K, it has been shown that the performance of the sample remains similar or even better than when fresh, due to an increased OSC. Thus, the reduction of CO and hydrocarbon emissions during start could be achieved by situating the catalytic converter nearer the exhaust to the engine, where the catalyst will be heated faster. 相似文献
32.
Gruffat D De La Torre A Chardigny JM Durand D Loreau O Sébédio JL Bauchart D 《Lipids》2003,38(2):157-163
Hepatic metabolism of the two main isomers of CLA (9cis-11 trans, 10trans-12cisC18∶2) was compared to that of oleic acid (representative of the main plasma FA) in 16 rats by using the in vitro method of incubated liver slices. Liver tissue samples were incubated at 37°C for 17h under an atmosphere of 95% O2/5%CO2 in a medium supplemented with 0.75 mM of FA mixture (representative of circulating nonesterified FA) and with 55 μM [1-14C]9cis-11 trans C18∶2, [1-14C]10trans-12cis C18∶2, or [1-14C]oleate. The uptake of CLA by hepatocytes was similar for both isomers (9%) and was three times higher (P<0.01) than for oleate (2.6%). The rate of CLA isomer oxidation was two times higher (49 and 40% of incorporated amounts of
9cis-11 trans and 10trans-12 cis, respectively) than that of oleate (P<0.01). Total oxidation of oleate and CLA isomers into [14CO2] was low (2 to 7% of total oxidized FA) compared to the partial oxidation (93 to 98%) leading to the production of [14C] acid-soluble products. CLA isoemrs escaping from catabolism were both highly desaturated (26.7 and 26.8%) into conjugated
18∶3. Oleate and CLA isomers were mainly esterified into neutral lipids (30%). They were slowly secreted as parts of VLDL
particles (<0.4% of FA incorporated into cells), the extent of secretion of oleate and of 10trans-12 cis being 2.2-fold higher than that of 9cis-11 trans (P<0.02). In conclusion, this study clearly showed that both CLA isomers were highly catabolized by hepatocytes, reducing their
availability for peripheral tissues. Moreover, more than 25% of CLA escaping from catabolism was converted into conjugated
18∶3, the biological properties of which remain to be elucidated. 相似文献
33.
Cairns Robert B.; Gariépy Jean-Louis; Hood Kathryn E. 《Canadian Metallurgical Quarterly》1990,97(1):49
The central questions of social development—from the roots of mother–infant attachment to the plasticity of aggressive behavior—pivot on the relations between genetic and ontogenetic sources of variance. It is proposed that (a) developmental, experiential, and microevolutionary processes typically collaborate, rather than compete, in achieving social adaptation; (b) social behavior patterns are mostly closed to modification in the course of development and across generations, but avenues of vulnerability exist in ontogeny and microevolution for dynamic, rapid, and reversible changes in key features; (c) a general avenue for change is delay or acceleration in the developmental onset of one or more features of the behavior pattern, which in turn modifies the functions and properties of the adaptive configuration; and (d) the features of social behavior that are open to rapid change in ontogeny should be open as well to rapid changes in microevolution, although different underlying processes may be involved. Empirical findings from the investigation of aggressive interactions are used to illustrate this proposal on the dual genesis and coincident adaptation of social behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Carole Marques Ludovic D’auria Patrice D. Cani Chiara Baccelli Raoul Rozenberg Nike L. Ruibal-Mendieta Géraldine Petitjean Dominique L. Delacroix Joëlle Quetin-Leclercq Jean-Louis Habib-Jiwan Marc Meurens Nathalie M. Delzenne 《Food chemistry》2007,100(3):1265-1271
The assessment of the glycemic index (GI) seems to be an important parameter to take into account in order to better understand the physiologic effects of foods with high carbohydrate levels. Among cereals, which are major sources of carbohydrates, spelt (Triticum spelta L.) has been considered as particularly interesting from a nutritional point of view. The aim of this study was to evaluate in vivo the GI of white spelt bread in healthy subjects. The wheat (Triticum aestivum L.) white bread was used as reference food. To avoid differences in the production of both breads, spelt and wheat breads were baked under the same controlled conditions. Results showed that the glycemic profile of spelt white bread was not different from that of wheat white bread (GI of 93 ± 9). The area under the glycemic curve significantly and negatively correlated to fasting glycemia and carbohydrate intake during evening meals preceding the test. In conclusion, the glycemic response to spelt bread was similar to that of wheat bread. However, in order to avoid more inter-individual variability, our data supports the importance to propose standardised carbohydrate content for the last meal before evaluating the GI of food. 相似文献
35.
Three bored piles were built and tested at the National Geotechnical Experimentation Sites, at Texas A&M University, to gather data on the reliability of large-strain dynamic methods to predict the static capacity of bored piles. The three piles had a nominal diameter of 0.915 m, a nominal length of 10 m, and some planned and unplanned defects. The piles were first subjected to a static load test and then four companies were asked to perform dynamic tests—namely, Statnamic and drop weight tests—and predict the static load test results. The paper shows the comparison between predicted and measured results. 相似文献
36.
Vasily Smirnov Olivier Grunewald Jean Muller Christina Zeitz Carolin D. Obermaier Aurore Devos Valrie Pelletier Batrice Bocquet Camille Andrieu Jean-Louis Bacquet Elodie Lebredonchel Saddek Mohand-Saïd Sabine Defoort-Dhellemmes Jos-Alain Sahel Hlne Dollfus Xavier Zanlonghi Isabelle Audo Isabelle Meunier Elise Boulanger-Scemama Claire-Marie Dhaenens 《International journal of molecular sciences》2021,22(12)
Variants of the TTLL5 gene, which encodes tubulin tyrosine ligase-like family member five, are a rare cause of cone dystrophy (COD) or cone-rod dystrophy (CORD). To date, only a few TTLL5 patients have been clinically and genetically described. In this study, we report five patients harbouring biallelic variants of TTLL5. Four adult patients presented either COD or CORD with onset in the late teenage years. The youngest patient had a phenotype of early onset severe retinal dystrophy (EOSRD). Genetic analysis was performed by targeted next generation sequencing of gene panels and assessment of copy number variants (CNV). We identified eight variants, of which six were novel, including two large multiexon deletions in patients with COD or CORD, while the EOSRD patient harboured the novel homozygous p.(Trp640*) variant and three distinct USH2A variants, which might explain the observed rod involvement. Our study highlights the role of TTLL5 in COD/CORD and the importance of large deletions. These findings suggest that COD or CORD patients lacking variants in known genes may harbour CNVs to be discovered in TTLL5, previously undetected by classical sequencing methods. In addition, variable phenotypes in TTLL5-associated patients might be due to the presence of additional gene defects. 相似文献
37.
Carlos Israel Molina François-Marie Gibon Jean-Louis Duprey Jean-Remy D. Guimarães 《The Science of the total environment》2010,408(16):3382-2753
We have evaluated the mercury and methylmercury transfers to and within the macroinvertebrate communities of a floodplain lake of the Beni River basin, Bolivia, during three hydrological seasons and in two habitats (open water and vegetation belt). Using the stable isotopes δ13C and δ15N, six trophic chains were identified during a previous study. Four are based on only one source: seston, organic matter from the bottom sediment, periphyton and macrophytes. Two are based on mixed sources (seston and periphyton in one case, periphyton and macrophytes in the other). During sampling, we found only one taxon that had surface sediment organic matter as food source and very few taxa whose trophic source was constituted by macrophytes. The periphyton was the most important source during all seasons; it produced the longest chain, with three trophic positions. Whatever the season and trophic source, all collected macroinvertebrates contained methyl mercury and the latter was biomagnified in all trophic chains that we identified. The biomagnification of methylmercury through invertebrate trophic chains accurately reflected the existence and length of these chains. Biomagnification was virtually non-existent in the sediment-based chain, low and restricted to the dry season in the macrophyte-based chain. It was significant in the seston-based chain, but limited by the existence of only two trophic levels and restricted to the wet season. Finally, it was very effective in the periphyton-based chain, which offers the highest rate of contamination of the source but, above all, the largest number of trophic levels. 相似文献
38.
Vidu A Dufau L Bannwarth L Soulier JL Sicsic S Piarulli U Reboud-Ravaux M Ongeri S 《ChemMedChem》2010,5(11):1899-1906
Herein we describe the synthesis and HIV-1 protease (PR) inhibitory activity of 16 new peptidomimetic molecular tongs with a naphthalene scaffold. Their peptidic character was progressively decreased. Two of these molecules exhibited the best dimerization inhibition activity toward HIV-1 wild-type and multimutated ANAM-11 proteases obtained to date for this class of molecules (~40?nM for wild-type PR and 100?nM for ANAM-11 PR). Although the peptidic character of one molecular tong was completely suppressed, the mechanism of inhibition and inhibitory potency toward both proteases were maintained. 相似文献
39.
During the study presented in this article, we compared two highly energy-efficient lighting scenarios for evening office lighting (i.e. electric lighting that is typically used for approxiamately 2 h in the evening). The first of these lighting scenarios (referred to as “Reference”-scenario, Lighting Power Density or LPD of 4.5 W/m2) has been successfully in use in many office rooms of the Solar Energy and Building Physics Laboratory’s experimental building, located on the campus of the Swiss Federal Institute of Technology in Lausanne, for several years. The second lighting scenario (referred to as “Test”-scenario, Lighting Power Density of 3.9 W/m2) is more energy-efficient, creates higher workplane illuminances but leads to an increased risk of discomfort glare. The aim of this study was to meticulously compare the two lighting scenarios in order to find a lighting solution for evening office lighting that offers an optimal trade-off between energy-efficiency, visual comfort and visual performance. 相似文献
40.
Passive Phasing in a Coherent Laser Array 总被引:1,自引:0,他引:1
Corcoran C.J. Durville F. 《IEEE journal of selected topics in quantum electronics》2009,15(2):294-300
A coherent array of fiber lasers in a self-Fourier cavity is described and analyzed. With individual regenerative feedback added to each fiber laser, the integrated gain in each individual fiber is a function of its cold cavity phase shift (fiber length). This results in a gain-dependent phase shift due to the Kramers-Kronig relations, and has been shown to partially compensate for the random differences in fiber lengths often encountered in coherent fiber arrays. A coupled cavity analysis of the active gain elements and the passive external cavity is performed and a self-consistent fundamental supermode determined. The output phase distribution of the array is determined based on a random distribution in fiber lengths. The Strehl ratio of this phase distribution is calculated and compared to experimental data. 相似文献