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51.
Sy Thomas; Shore Lynn M.; Strauss Judy; Shore Ted H.; Tram Susanna; Whiteley Paul; Ikeda-Muromachi Kristine 《Canadian Metallurgical Quarterly》2010,95(5):902
On the basis of the connectionist model of leadership, we examined perceptions of leadership as a function of the contextual factors of race (Asian American, Caucasian American) and occupation (engineering, sales) in 3 experiments (1 student sample and 2 industry samples). Race and occupation exhibited differential effects for within- and between-race comparisons. With regard to within-race comparisons, leadership perceptions of Asian Americans were higher when race–occupation was a good fit (engineer position) than when race–occupation was a poor fit (sales position) for the two industry samples. With regard to between-race comparisons, leadership perceptions of Asian Americans were low relative to those of Caucasian Americans. Additionally, when race–occupation was a good fit for Asian Americans, such individuals were evaluated higher on perceptions of technical competence than were Caucasian Americans, whereas they were evaluated lower when race–occupation was a poor fit. Furthermore, our results demonstrated that race affects leadership perceptions through the activation of prototypic leadership attributes (i.e., implicit leadership theories). Implications for the findings are discussed in terms of the connectionist model of leadership and leadership opportunities for Asian Americans. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Public clients have been identified as drivers of architectural, engineering and construction (AEC) industry change through their implementation of building information modelling (BIM). Yet, little is known of this implementation process and the associated challenges. This study aims to increase the understanding of what intra- and inter-organizational challenges that arise when a large Swedish public infrastructure client implements BIM to change the work practices of the actors in the Swedish AEC industry. The IT business value model allows for understanding the public client’s implementation of BIM as an IT-supported change process and for understanding the associated intra- and inter-organizational challenges. The findings show nine categories of intra- and inter-organizational challenges related to, for example, demanding BIM in procurement and creating incentives for BIM implementation. The findings show that intra-organizational challenges related to a top-down implementation of BIM, while inter-organizational challenges related to a bottom-up implementation. The impact of these challenges on the public client’s ability to drive AEC industry change by implementing BIM is discussed. The findings contribute with the client perspective to studies on BIM implementation and with an increased understanding of the challenges associated with implementing IT-supported change processes. 相似文献
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Derya Akcan Susanna Axelsson Christina Bergh Thomas Davidson Måns Rosén 《Scientometrics》2013,96(1):297-303
Citation frequencies and journal impact factors (JIFs) are being used more and more to assess the quality of research and allocate research resources. If these bibliometric indicators are not an adequate predictor of research quality, there could be severe negative consequences for research. To analyse to which extent citation frequencies and journal impact factors correlate with the methodological quality of clinical research articles included in an SBU systematic review of antibiotic prophylaxis in surgery. All 212 eligible original articles were extracted from the SBU systematic review “Antibiotic Prophylaxis in Surgery” and categorized according to their methodological rigourness as high, moderate or low quality articles. Median of citation frequencies and JIFs were compared between the methodological quality groups using Kruskal–Wallis non-parametric test. An in-depth study of low-quality studies with higher citation frequencies/JIFs was also conducted. No significant differences were found in median citation frequencies (p = 0.453) or JIFs (p = 0.185) between the three quality groups. Studies that had high citation frequencies/JIFs but were assessed as low-quality lacked control groups, had high dropout rates or low internal validity. This study of antibiotic prophylaxis in surgery does not support the hypothesis that bibliometric indicators are a valid instrument for assessing methodological quality in clinical trials. This is a worrying observation, since bibliometric indicators have a major influence on research funding. However, further studies in other areas are needed. 相似文献
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56.
Pizza F Contardi S Ferlisi M Mondini S Cirignotta F 《Accident; analysis and prevention》2008,40(2):602-609
BACKGROUND: Sleepiness related car accidents are common in obstructive sleep apnoea syndrome (OSAS) patients. The objective measurements of sleepiness used in clinical setting quantify the tendency to fall asleep in quiet situations that are completely different from driving. METHODS: We studied 30 OSAS patients with subjective (subjective sleepiness scales) and objective (multiple sleep latency test, MSLT) sleepiness measurements, associated with driving simulation test (DST), previously validated in young healthy subjects. The results of subjective and objective sleepiness tests were compared with simulated driving performance in order to evaluate the suitability of our DST for measuring alertness. RESULTS: Subjective and objective sleepiness measurements were significantly correlated with driving performance on the simulator. The most significant correlates of sleepiness were the measures of the primary vehicle control task on the simulator: lane position variability and crash data. The comparison of DST and MSLT results suggested our driving simulated approach could be used to evaluate daytime sleepiness in the clinical setting of OSAS patients. CONCLUSIONS: Our DST is a suitable objective tool to detect sleepiness in OSAS patients, and could be useful in the clinical setting of sleep medicine and research. 相似文献
57.
Andreas Hohenleutner Susanna Schmidbauer Rudolf Vasold Dominik Joosten Philipp Stoessel Herwig Buchholz Burkhard König 《Advanced functional materials》2012,22(16):3406-3413
This work reports the combinatorial synthesis and screening of phosphorescent iridium complexes as solution processable emitters for OLEDs. The approach taken here allows for the rapid synthesis, isolation, spectroscopic characterization and identification of the libraries based on chromatographic methods. Subsequent analysis of the irradiation induced degradation provides insight on the stability of the complexes under continuous excitation. The method is versatile and can easily be applied to other metal complexes or organic dyes for various applications, e.g., in electroluminescence, photovoltaics and sensing. 相似文献
58.
Alexis Marsol-Vall Antoni Delpino-Rius Jordi Eras Mercè Balcells Ramon Canela-Garayoa 《Food Analytical Methods》2014,7(2):465-471
A fast and reliable method for the quantification of patulin using ultra high performance liquid chromatography coupled to a photodiode array detector was developed and validated for the analysis of several apple-based foodstuffs. Sample preparation was based on the QuEChERS procedure. Samples were extracted with acetonitrile and partitioned with a mixture of sodium citrate, NaCl, and Mg2SO4. The cleanup step was performed using dispersive SPE mixed with Mg2SO4 and PSA. This step was carried out twice in order to improve chromatographic results. The method was validated in spiked cloudy apple juice, apple puree, apple yogurt, beer with apple juice, and cider and applied to 24 commercial samples. The limits of detection and limits of quantification were ≥0.4 and ≥2 ng/g, respectively. Both were below the maximum legal limit established by the European Union. Recoveries for all the matrices were between 78.4 and 94.7 % while relative standard deviations were between 3.8 and 10.4 %. Patulin was detected on four apple juices from concentrate, one cloudy apple juice from an eco-store, and one beer. Nevertheless, the highest concentration found was 25.4 ng/g. 相似文献
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60.
Wenke Friedrichs Bastian Ohler Walter Langel Susanna Monti Susan Köppen 《Advanced Engineering Materials》2011,13(10):B334-B342
Classical molecular dynamics simulations of tropocollagen molecules on rough titania surfaces are presented. On the basis of plane rutile (100), two models for surface roughness have been adopted: (1 × 3) microfacets with dimensions of less than 14 Å had only minor influence on the adsorption of a triple helical structure with a diameter of about 16 Å. After increasing the roughness by terraces, steric hindrance of helix binding was observed. A model for telopeptide capping of the collagen triple helices was developed. The highly flexible telopeptide structures mediated adsorption on the surface and inserted into grooves of both surface models. The telopeptide β‐turn motifs at the C‐terminus of the tropocollagen interact with specific receptor regions of the triple helices. This intermolecular process seems to be entropy driven and may be the first step of assembling helices to ordered fibrils. Interaction between telopeptide and triple helix seems to be in competition with the rather enthalpy controlled surface adsorption of single collagen molecules. 相似文献