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We discuss the introduction of an information system where the dominant coalition claimed project success. While the key users did not use the system as intended and the project goals were not achieved, the project committee reported success to the top management board. Using a multi-methodological approach, we can follow how different stakeholders attributed different meanings to the system introduced over time. The rhetorical tools used are analysed using a narrative methodology. We draw on the social construction of technology and use the concept of relevant social groups to understand the different interests influencing the organisational dynamics. We complement this approach by employing the concepts of organisational power and cultural fit between the new system and the different subcultures. We found that this multiple approach explains well how the acceptance of the new software processes was interpreted differently within the organisation, and also by the software supplier. Although limited, our case study reveals the process of socially constructing the success or failure of an information system using this multiple research approach. We compare our results with the literature on IS failures and we consider the value of combining constructionist and critical approaches through a narrative methodology.  相似文献   
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Summary The 2,2 bis(4-ethynylphenyl)hexafluoropropane is prepared via an original synthesis's process using a substitution of 2,2 bis(4-triflatephenyl) hexafluoropropane by trimethylsilyl acetylene. In this process ZnO is used to remove the triflate anion formed during the reaction.This diacetylenic compound melts at 37–38°C, exhibits an onset of polymerization at 120°C. After thermal treatment at 250°C, the obtained network shows a softening point at 300°C. This network remains stable in air up to 435°C.  相似文献   
114.
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   
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Psychophysiological reactivity to nonaversive (1-KHz, 70-db tones) and aversive stimuli (shock) was examined in nonalcoholic men with multigenerational family histories (MFH) of alcoholism and family history negative (FH–) men, while sober and after consuming alcohol. In comparison with FH– Ss, sober MFH Ss had significantly larger skin conductance (SC) orienting responses (ORs), shorter OR latencies, slower habituation rates to the tones, and larger increases in heart rate and vasoconstriction to the shock. Alcohol dampened the magnitude of the SC-OR to the tones and the degree of cardiovascular reactivity to the shocks and increased the habituation rate to the tones in MFH Ss only. Alcohol consumption also increased the SC-OR recovery time in FH– Ss only. The MFH Ss' pattern of psychophysiological hyperreactivity is discussed in terms of a potential dysfunction in stimulus–response regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The authors have translated the Nisonger Child Behavior Rating Form (Nisonger CBRF) into French. The resulting Grillee d'évaluation comportementale pour enfants Nisonger (GéCEN) was completed by 383 parents and 328 teachers. The congruence coefficients between the factor structure obtained from the Québec data and that obtained from the American data are also presented. Except for the congruence coefficient for the irritability scale from the GéCEN-teacher, the congruence coefficients for the parent and teacher profiles exhibit a good level of factor stability between the Nisonger CBRF, and the GéCEN. The internal consistency indicators are good to excellent for the GéCEN-parent and the GéCEN-teacher. The clinical applications of this dual diagnosis assessment tool (mental retardation and psychopathology) among children and teenagers are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The fatty acid (FA) composition of food is requested for labelling purposes and food composition tables. Suitable analytical methods for labelling purposes must be able to efficiently identify and accurately quantify FA as swiftly and cheaply as possible. This study evaluated a middle‐length highly polar column, the BPX‐70 60‐m column, to balance analysis efficiency and duration. The use of a 60‐m column led to the loss of data on minor FA but a gain in analysis time. The column was evaluated by analysing the FA composition of ten cookies made with different kinds of fats, including milk fat, and pure and/or partially hydrogenated vegetable oils. The FA elution order in this GC phase has been poorly documented in the literature compared to equivalent highly polar CPSil‐88 and SP‐2460 GC phases. Co‐elutions and overlaps on the BPX‐70 column were studied and commented upon. Overall, the BPX‐70 60‐m column could be used for rapid screening of the FA composition of simple foods. Analysis of the FA composition of a complex matrix, such as a dairy product, and specific analysis of trans‐FA required a longer highly polar column, possibly after fractionation by silver‐ion liquid chromatography. Compared to other GC phases, the BPX‐70 enabled effective isolation of 18:3 isomers although these isomers co‐eluted with 20:1 isomers on other highly polar GC phases. However, some CLA isomers co‐eluted with other FA on this column, and a specific analysis of these special FA would require another phase and/or different chromatographic conditions.  相似文献   
120.
Polystyrene (PS) chains with molecular weights comprised between 15,000 and 60,000 g/mol and narrow polydispersities were successfully grown from the surface of silica nanoparticles by nitroxide-mediated polymerization (NMP). Small angle X-ray scattering was used to characterize the structure of the interface layer formed around the silica particles, and at a larger scale, dynamic light scattering was used to determine the hydrodynamic diameter of the functionalized silica suspension. In a second part, blends of PS-grafted silica particles and pure polystyrene were prepared to evaluate the influence of the length of the grafted PS segments on the viscoelastic behavior of the so-produced nanocomposites in the linear viscoelasticity domain.Combination of all these techniques shows that the morphology of the nanocomposite materials is controlled by grafting. The steric hindrance generated by the grafted polymer chains enables partial destruction of the agglomerates that compose the original silica particles when the latter are dispersed either in a solvent or in a polymeric matrix.  相似文献   
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