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101.
Examined the relationships among social support knowledge, supportive behavior, intimacy with one's spouse, and satisfaction with support provided by one's spouse among 41 Israeli kibbutz couples. The hypothesis that support knowledge and support behavior influence the intimacy between couples and increase satisfaction with spouse's social support efforts was tested. Alternative causal mechanisms are explored with simultaneous equation modeling. Results indicate that satisfaction with social support behavior by one's spouse is mediated entirely by intimacy with one's spouse. Results also indicate that partner's knowledge about social support behavior directly affects intimacy and indirectly generates social support satisfaction independent of actual supportive behavior. The findings do not differ by sex. The consistency of the findings with family behavior exchange theory and implications for marital therapy are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
Recent foodborne outbreaks have linked infection by enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 to the consumption of contaminated lettuce. Contamination via food handler error and on-the-farm contamination are thought to be responsible for several outbreaks. Though recent studies have examined the application of EHEC to store-bought lettuce, little is known about the attachment of EHEC to growing plants. We investigated the association of lettuce seedlings with EHEC O157:H7 strains implicated in lettuce or fruit outbreaks using hydroponic and soil model systems. EHEC strains that express the green fluorescent protein were observed by stereomicroscopy and confocal laser scanning microscopy to determine adherence patterns on growing lettuce seedlings. Bacteria adhered preferentially to plant roots in both model systems and to seed coats in the hydroponic system. Two of five nonpathogenic E. coli strains showed decreased adherence to seedling roots in the hydroponic system. EHEC was associated with plants in as few as 3 days in soil, and contamination levels were dose-dependent. EHEC levels associated with young plants inoculated with a low dose suggested that the bacteria had multiplied. These data suggest that preharvest crop contamination via contaminated irrigation water can occur through plant roots.  相似文献   
103.
A new method for integrated design of passive and active elements is presented. Rather than the existing qualitative selection of parameters for passive elements, a quantitative approach is proposed that finds optimal active and passive parameters with respect to an H2/H performance requirement. This new approach automatically yields passive designs when the given performance limits are high enough and active (hybrid) designs when the given performance constraints are stringent. Furthermore, our algorithm finds the special performance requirement (the peak of the frequency response) that cannot be satisfied by any passive design. Hence this article shows how to determine when control is required rather than assuming a priori that it is or is not required. A simple design method given herein yields either passive, active, or hybrid designs depending only on the level of the performance constraints that are specified in the statement of the problem.  相似文献   
104.
The seasonal performance of space cooling systems generally depends on indoor and outdoor temperatures and humidities and on the ratio between actual cooling loads and cooling equipment size. In principle, any given weather condition and desired indoor dry-bulb temperature calls for an interactive application of psychrometrics and equipment performance curves until satisfactory indoor conditions are derived for which both sensible and latent cooling loads equal sensible and latent heat removal rates. This paper presents a simplified approach that derives the indoor wet-bulb temperature in close form for both cases when the cooling system condenses water from the space and when it does not. This approach relies on a local linearization of the psychrometric chart in the region of interest for indoor comfort conditions. Performance curves for total and sensible capacity and for the electric power input were derived for several different residential air-to-air reciprocating compressive cooling systems. The performance curves are empirical fits to manufacturer's data or to laboratory results. The predictions of the simplified method were compared with DOE-2 when calculating space cooling consumption for a residence in both a hot arid and in a hot humid climate. The comparison showed excellent agreement both for hour-by-hour calculations and for monthly calculation of this method are sufficiently simple to be applicable to micro-computers and pocket calculators.  相似文献   
105.
Six measures of divergent thinking were administered to 825 men ranging in age from 17 to 101 over the period from 1959 to 1972; repeat administrations were given to a subset of 278 men after a 6-year interval. Cross-sectional analyses showed curvilinear trends, with an increase in scores for men under 40 and a decline thereafter. Repeated measures analyses on subjects initially aged 33 to 74 generally replicated this finding, whereas cross-sequential analyses suggested a decline for all cohorts tested at a later time. Additional analyses suggested that not all of the decline could be attributed to reduced speed of response production. These longitudinal findings confirm earlier cross-sectional reports of decline in divergent thinking abilities with age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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108.
Previous studies have revealed that if mallard ducklings are given social experience with broodmates after their initial exposure to a stuffed mallard (Anas platyrhynchos) hen, they later show a visual preference for the familiar mallard over an unfamiliar redhead (Aythya americana) model. Birds kept in isolation do not make this difficult discrimination. We examined when the social experience with siblings must occur in order to contribute to maternal imprinting. We allowed 24-hr-old domestic mallard ducklings to follow a stuffed mallard hen for 30 min (training). This experience resulted in a preference for the familiar mallard over the unfamiliar redhead hen in a simultaneous choice test 48 hrs after hatching only if the birds were allowed social experience with broodmates after the training trial (i.e., from 24 to 48 hrs). Thus the visual features of the mallard hen that are necessary in order to distinguish it from the redhead hen become consolidated only after more than 1 hr into the posttraining social rearing; we term this process retroactive excitation. These results provide evidence of a nonobvious experiential contribution that conspecifics make to the development of species-typical social behavior. They also suggest that some learning and memorial processes may operate rather differently in adults and immature animals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
An account of the use of landscape as subject-matter as a basis for the exploration of personal concerns and the search for self by various 20th Century photographers. Particular reference is made to the landscape photography of Eugene Atget, Edward Weston and Bill Brandt.  相似文献   
110.
This paper introduces a new nonlinear filtering structure for filtering image data that have been corrupted by both impulsive and nonimpulsive additive noise. Like other nonlinear filters, the proposed filtering structure uses order-statistic operations to remove the effects of the impulsive noise. Unlike other filters, however, nonimpulsive noise is smoothed by using a maximum a posteriori estimation criterion. The prior model for the image is a novel Markov random-field model that models image edges so that they are accurately estimated while additive Gaussian noise is smoothed. The Markov random-field-based prior is chosen such that the filter has desirable analytical and computational properties. The estimate of the signal value is obtained at the unique minimum of the a posteriori log likelihood function. This function is convex so that the output of the filter can be easily computed by using either digital or analog computational methods. The effects of the various parameters of the model will be discussed, and the choice of the predetection order statistic filter will also be examined. Example outputs under various noise conditions will be given.  相似文献   
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