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51.
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
52.
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
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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
55.
Yan LY Li W Mesgari S Leong SS Chen Y Loo LS Mu Y Chan-Park MB 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(19):2758-2768
Three isomers of chondroitin sulfate (CS), i.e., CS-A, CS-B, and CS-C, are investigated as nanotube dispersants and are found to have vastly different abilities to disperse single-walled carbon nanotubes (SWNTs) in water due to their different intramolecular interactions. Only CS-A and CS-C effectively disperse SWNTs into small bundles or individual tubes while CS-B disperses SWNTs poorly. Computer simulation and circular dichrosim show that neat CS-A and CS-C have weak intramolecular hydrogen bonding and extended conformations in solution resulting in energetically more favorable interactions with nanotubes. CS-B has relatively strong intramolecular Coulombic interaction and more alpha-helical secondary structure in solution resulting in energetically less favorable interaction with the nanotubes. Atomic force microscopy images show helical wrappings of CS-A and CS-C around the SWNTs. Transmission electron microscopy corroborates the helical wrapping of CS-A. Different isomeric forms of a polymer can have vastly different dispersing power because of their different intramolecular interactions and conformations. The easy removability of CS-A from nanotubes is confirmed with X-ray photoelectron spectroscopy showing almost no detectable sulphur content after washing with water and by application of washed CS-A dispersed SWNTs in field-effect transistors. 相似文献
56.
Galbiati Susanna; Recla Monica; Pastore Valentina; Liscio Mariarosaria; Bardoni Alessandra; Castelli Enrico; Strazzer Sandra 《Canadian Metallurgical Quarterly》2009,23(1):40
Traumatic brain injury (TBI) frequently affects both the basic and the superordinate components of attention; deficits vary according to patient age. This study evaluated the efficacy of a specific remediation intervention for attention. Sixty-five TBI patients (aged 6?18 years) with attention deficit were assessed at baseline and at 1-year follow-up: 40 patients received attention-specific neuropsychological training for 6 months, and the control group comprised 25 patients. Cognitive assessment included a Wechsler Intelligence Scale (e.g., A. Orsini, 1993) and the Continuous Performance Test II (CPT II; C. K. Conners, 2000). The Vineland Adaptive Behavior Scales (VABS; S. Sparrow, D. Balla & D. V. Cicchetti, 1984) was administered to assess the treatment's ecological validity. At baseline, all patients presented with a mild intellectual disability and pathological scores on the CPT II. At follow-up, significant differences were found between the 2 groups on the CPT II and VABS: The clinical group improved more than the control group. Specific remediation training for attention, including a combination of a process-specific approach and metacognitive strategies, significantly improved attention performance. Improvement in attention skills also affected adaptive skills positively. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Tuomas Ihme Minna Pikkarainen Susanna Teppola Jukka Kääriäinen Olivier Biot 《Empirical Software Engineering》2014,19(4):1144-1168
Software variability is an ability to change (configure, customize, extend) software artefacts (e.g. code, product, domain requirements, models, design, documentation, test cases) for a specific context. Optimized variability management can lead a software company to 1) shorter development lead time, 2) improved customer and improved user satisfaction, 3) reduced complexity of product management (more variability, same $) and 4) reduced costs (same variability, less $). However, it is not easy for software companies, especially small and medium size of enterprises to deal with variability. In this paper we present variability challenges and used practices collected from five SMEs. Our study indicates that increased product complexity can lead growing SMEs to the time-consuming decision-making. Many of the analyzed medium size of companies also expect improved tool support to help them to boost their productivity when managing increasingly complex products and increasing amount of variants In fact, in many of the analysed SMEs, a high level of automation in design, release management and testing are or become a key factor for market success By introducing the challenges and used practices related to variability the paper deepens understanding of this highly relevant but relatively under-researched phenomenon and contributes to the literature on software product line engineering. 相似文献
59.
White Carrie V.; Pascarella Ernest T.; Pflaum Susanna W. 《Canadian Metallurgical Quarterly》1981,73(5):697
30 learning-disabled Hispanic, White, and Black children (mean IQ 88.60 and mean age 11.73 yrs) were randomly assigned to 2 conditions focusing on sentence comprehension: a sentence anagram/word grouping treatment and a more traditional sentence study treatment. With age, IQ, and pretest comprehension (Gates-MacGinitie Reading Tests) controlled, Ss in the sentence anagram/word grouping condition had significantly higher cloze scores than Ss in the sentence study group. The greatest achievement benefits associated with the anagram treatment, however, accrued to Ss with higher initial reading achievement. As level of pretreatment achievement decreased, the magnitude of the treatment differences also tended to decrease. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Speranza M Satta M Piccirillo S Rondino F Paladini A Giardini A Filippi A Catone D 《Mass spectrometry reviews》2005,24(4):588-610
Chiral recognition is a fundamental phenomenon in life sciences, based on the enantioselective complexation of a chiral molecule with a chiral selector. The diastereomeric aggregates, formed by complexation, are held together by a different combination of intermolecular forces and are therefore endowed with different stability and reactivity. Determination of these forces, which are normally affected in the condensed phase by solvent and supramolecular interactions, requires the generation of the diastereomeric complexes in the isolated state and their spectroscopic investigation. This review deals with chiral recognition in the gas phase through the application of laser-resolved mass spectrometric techniques (R2PI-TOF and RET-MS). The measurement of the fragmentation thresholds of diastereomeric clusters by these techniques allows the determination of the nature of the intrinsic interactions, which control their formation and affect their stability and reactivity. 相似文献