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31.
Although siblings are thought to be influential in child development, little is known about the influence of sibling status on the health of older adults. Using structural equation modeling, the authors created and tested a series of models with data from a sample (N = 3,968) of 1957 high school graduates from the Wisconsin Longitudinal Study. The results indicated that socioeconomic status of origin, adolescent aptitude, and educational attainment did have significant total effects on health in later life, but sibling status did not. Adults who grew up in families of higher socioeconomic status and who had greater aptitude in high school attained more education, and this advantage, in turn, led to better health in later life. Although the final model was cross-validated, it was not equally plausible for men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
We have developed a multifocal optical fluorescence correlation spectroscopy system for parallel flow analyses. Multifocal excitation was made possible through a 4 x 1 diffractive optical fan-out element, which produces uniform intensity in all four foci. Autocorrelation flow analyses inside a 20 microm x 20 microm square microchannel, with the 4 x 1 fan-out foci perpendicular to the flow direction, made it possible to monitor different flows in all four foci simultaneously. We were able to perform cross-correlation flow analyses by turning the microstructure, thereby having all four foci parallel to the direction of flow. Transport effects of the diffusion as a function of flow and distance could then also be studied.  相似文献   
33.
Abstract— Color breakup is an artifact perceivable on field‐sequential‐color (FSC) displays, both in stationary and in moving images. In this work, a unique device and a method for measuring color breakup on stationary images is proposed. Rotating the field of view of a high‐speed measurement camera in milliseconds simulates saccadic behavior. The target can be a virtual display, a direct‐view display or a projector image. Captured images can be used for quantifying the color breakup of a target display. The results along with an exploration of their application to breakup characterization will be presented.  相似文献   
34.
Reviews the literature on predictable and unpredictable shock conditions relative to physiological measures of stressfulness and considers the possible role of stress-induced analgesia in both physiological and behavioral effects. Findings suggest that unpredictable conditions are physiologically more stressful than predictable conditions when Ss are exposed to them for one or a few sessions and when parameters of stress are relatively severe. However, predictable conditions may be more stressful than unpredictable conditions when sessions are long and extend over days and when parameters of stress are less severe. The effect of extended stress appears to depend on the physiological measure used. These findings are discussed in terms of the phasic vs chronic nature of predictable vs unpredictable stress and the organism's ability to adapt physiologically to these conditions. Data on stress-induced analgesia are also reviewed. It is concluded that stress-induced analgesia does not significantly contribute to either preference for predictable over unpredictable stress or to their differential physiological effects. (88 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Total hip replacement has become one of the most successful orthopaedic procedures. However, complications due to infections may give serious problems and have devastating consequences for the hip implant. The use of a temporary three-dimensional polymethylmethacrylate (PMMA) cement spacer may be an alternative to solve infections in hip implants, improving the lives of patients awaiting reimplantation. In order to evaluate their wear behaviour, five PMMA Spacer-G femoral heads were tested against five post-mortem pelves in a hip joint simulator with bovine calf serum as lubricant. The surface of the worn spacers was characterized by scanning electron microscopy (SEM) analysis; all the samples revealed a similar morphology, showing areas characterized by different degrees of wear. Particle debris was isolated from the lubricant and PMMA particles and bone fractions were quantified. The amount of debris was found to be higher than where no-temporary prostheses were used. However, this result is acceptable since wear debris is removed by lavage irrigation when the Spacer-G is explanted. On the basis of these data, it is considered that the use of the cement Spacer-G could be a promising approach to the treatment of complicated infections of the hip joint. Therefore, Spacer-G is worthy of further research.  相似文献   
37.
The marital relationship rarely exists in isolation and yet few studies have examined the multiple relationships experienced by most married people. This study used the Convoy Model of Social Relations to examine patterns of multiple relationships and well-being among men and women ages 22 to 79 years (N = 654). Cluster analyses identified profiles of relationship quality among people with spouse, family (children, mother, father), and a best friend (N = 451) and those married with family but no best friend (N = 202). Relationship profiles differed in quality and by gender, race, and age. Among people with best friends, having at least 2 high quality relations, not necessarily with a spouse, is associated with greater well-being. In contrast, among people without best friends, the spousal relation appears to be particularly important for well-being. Although family relationships (e.g., spouse) are important for well-being, interventions should consider the composition and quality of social networks to determine which relationships may need improvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
38.
Electrochromic tungsten oxide thin films were prepared by using an aqueous solution of Na2WO4·2H2O and dimethyl sulfate. Various techniques were used for the characterization of the films such as X-ray diffraction, cyclic voltammetry, SEM analysis and VIS-spectroscopy. The thin film durability was tested in an aqueous solution of LiClO4 (0.1 mol/dm3) for about 7000 cycles followed by cyclic voltammetry. No significant changes in the cyclic voltammograms were found, thus proving the high durability of the films.The optical transmittance spectra of coloured and bleached states showed significant change in the transmittance, which makes these films favorable for electrochromic devices.  相似文献   
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40.
In this paper the flood problem of the river Demer, a river located in Belgium, is discussed. First a simplified model of the Demer basin is derived based on the conceptual reservoir modeling concept. This model was calibrated to simulations results with a more detailed full hydrodynamic model. Afterwards, the focus is shifted to a nonlinear model predictive controller (NMPC) which is based on a new semi-condensed optimization procedure combined with a line search approach. Finally, simulations are performed based on historical data in which the NMPC is compared with the current control strategy used by the local water administration. Uncertainties are added to the rainfall predictions in order to assess the robustness of the NMPC.  相似文献   
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