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81.
The research aim was to select, compare, and analyze interventions and preventive actions from international bus companies to decrease bus drivers' occupational stress and sickness absenteeism. Through networking, international surveys, and literature study, 13 "natural experiments" were identified with an acceptable research design rating. Interventions were both work and person directed. Principles of worker participation were often followed. The variety in intervention programs, outcome measures, case evaluations, and methodological flaws makes it difficult to present a general picture of program effectiveness. However, analyses on more objective and more subjective outcomes do point at positive effects. This study suggests that stress prevention that combines adequate interventions and proper implementation may be beneficial to both the employee and the company. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Prostaglandins (PG) are primary regulators of reproductive function. In ruminants, the relative production of PGE2 and PGF2alpha determines the return to a new oestrous cycle or to the establishment of pregnancy in response to a viable embryo. PG action depends on biosynthesis, transport and interaction with their receptors, which are all expressed differentially during the oestrous cycle. PGs are, however, local mediators and thus the onsite degradation by enzymes such as 15-hydroxyprostaglandin dehydrogenase (HPGD), also known as 15-PGDH, is another factor to consider in the regulation of physiological action. Little information is available on PG catabolism in the endometrium during the oestrous cycle or early pregnancy. The purpose of this study was to clone the bovine 15-PGDH, produce the recombinant protein and generate a specific antibody to study its activity and its expression in the endometrium during the oestrous cycle. We have found that the bovine 15-PGDH is highly homologous to the rat and human isoforms. 15-PGDH is localized principally in the glandular epithelium and to a lesser extent in stromal and luminal epithelial cells. The enzyme expression is regulated during the oestrous cycle and it reaches its maximal level on days 16-18. Transient expression is observed in luminal epithelial and trophoblast cells on day 21 of pregnancy. The mRNA is expressed at a constant high level throughout the cycle. The activity of the recombinant 15-PGDH was also tested and was found comparable for PGF2alpha and PGE2. These data suggest that 15-PGDH contributes to the tight regulation of PG action in the endometrium especially at the critical period of recognition of pregnancy.  相似文献   
83.
Using a within-subject design, this study investigated the situational-specificity hypothesis, namely that alcohol outcome expectancies (AOEs), subjective evaluations of AOEs, and the speed with which AOEs are accessed from memory vary as a function of environmental setting. Thirty-nine undergraduates (20 women), of legal drinking age, responded to the Comprehensive Effects of Alcohol questionnaire (K. Fromme, E. Stroot, & D. Kaplan, 1993) that was presented on a laptop computer in 2 counterbalanced contexts: a laboratory setting and an on-campus bar. Response latencies served as dependent measures for memory accessibility. Consistent with previous research (A.-M. Wall, S. A. McKee, & R. E. Hinson, 2000), evidence in support of the situational-specificity hypothesis was found. Specifically, environmental context influenced undergraduates' expectations concerning alcohol's effects and subjective evaluations of AOEs, as well as the speed with which specific AOEs were accessed from memory. Overall, these findings suggest the need for greater attention to situational variation in AOEs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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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   
87.
Facets of prior experience and the effectiveness of inclusive design   总被引:1,自引:0,他引:1  
Research in inclusive design has shown the importance of prior experience for the usability of interactive products. Prior experience, however, is an ill-defined and inconsistently used construct. A number of different definitions and operationalisations of experience exist, but the differing power of these operationalisations to predict the usability of products for older users has rarely been investigated systematically. This study seeks to fill that gap. It is argued that the construct of experience has at least three components. It is proposed that two of these components, exposure and competence, are directly relevant for the current discussion about prior experience in inclusive design and that they can predict to different degrees the usability of a product for older users. In an empirical study, these facets of expertise are each operationalised on three levels of specificity and their impact on usability is assessed. The results show that measures of competence predict usability variables more strongly than measures of exposure and that levels of medium and high specificity are the best predictors. The application of inclusive design principles to a redesigned version of a ticket vending machine—although not resulting in a difference of overall usability—changed the impact of prior experience on usability measures implying an enhanced inclusiveness of the redesign with regard to prior experience. The implications of these findings for the effectiveness of inclusive design for older users are discussed.  相似文献   
88.
Plasmon resonance of gold nanoparticles is responsible of the electromagnetic (EM) Surface Enhanced Raman Scattering (SERS) effect. Interaction of an amorphous matrix with a SERS substrate was studied. Thin films with different thickness of amorphous TiO2 coated on a Klarite® substrate show a 100 times enhancement of the Raman signal. Distance dependence of the SERS interaction was shown to be less than 60 nm.  相似文献   
89.
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   

90.
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   
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