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61.
Hypothesized that, when the degree of crowding is manipulated by varying group size in cages of equal size, it is probable that crowded animals will engage in more contact than uncrowded animals. Home-cage observation of 24 male and 24 female deer mice indicates that crowded Ss do, in fact, engage in more contact behavior. Both home-cage observation and testing in pairs for pain-elicited aggression reveal that (a) crowded Ss display more agonistic behavior than uncrowded Ss, and (b) agonistic behavior increases with prolonged crowding. Support is obtained for the theory that the effect of crowding derives from contact with conspecifics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The reactive effect on mood of self-monitoring pleasant and unpleasant events was assessed. Forty-five females spent 28 days monitoring in one of four conditions: (a) pleasant events, (b) unpleasant events, (c) both, and (d) no monitoring. Motor activity level (pedometer recordings) and mood were also assessed daily. Class of event monitored was not found to influence mood. Correlations between mood and both pleasant and unpleasant events were found even with activity level partialed out. Implications for self-monitoring assessment in depression therapy programs and for models of depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
Angiotensin II (AII), found in seminal plasma, has been shown to stimulate capacitation in uncapacitated mammalian spermatozoa. The present study investigated the location of AII receptors on spermatozoa and AII's mechanism of action. AT1 type receptors for AII are present on the acrosomal cap region and along the whole of the flagellum of both mouse and human spermatozoa. Because combinations of low concentrations of AII and either calcitonin or fertilization-promoting peptide (FPP), both known to regulate the adenylyl cyclase (AC)/cAMP signal transduction pathway, elicited a significant response, this study investigated the hypothesis that these peptides act on the same pathway. AII was shown to significantly stimulate cAMP production in both uncapacitated and capacitated mouse spermatozoa and this was associated with increases in protein tyrosine phosphorylation. Using an anti-phosphotyrosine antibody to visualize the location of tyrosine phosphoproteins within individual cells, AII significantly stimulated phosphorylation within 20 min in both the head, especially in the acrosomal cap region, and the flagellum, especially in the principal piece, of uncapacitated mouse spermatozoa; combined AII + FPP was stimulatory within 5 min. In addition, Western blotting revealed that AII stimulation increased phosphorylation in a number of tyrosine phosphoproteins in both uncapacitated and capacitated mouse spermatozoa, with some being altered only in the latter category of cells. These results support the hypothesis that AII stimulates AC/cAMP in mammalian spermatozoa.  相似文献   
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A brief history of man-made noise interference is provided. A series of examples of this type of radio interference points out the generally insidious?or in a few instances the somewhat ridiculous?nature and effects of man-made noise. It is demonstrated how the Pacific Missile Range and the Western Area Frequency Coordinator mitigate man-made noise by the use of area controls, engineering, testing, monitoring, training, and frequency management.  相似文献   
67.
Although iron-based permeable reactive barriers are gaining importance for treating groundwater contaminants, little is currently known about the effect of cosolutes on barrier longevity. Because of their corrosion inhibiting properties, dissolved silica species are of particular concern. This research investigates the effect of silica on the reduction of 1,1,1-trichloroethane by granular iron as a function of added silica concentration, pH, and duration of iron exposure to dissolved silica. Batch studies reveal that, at pH 8.5 and above, added silica concentrations as low as 0.17 mM cause a 30% reduction in the reactivity of iron. At higher silica concentrations, reactivity decreases by 65-75%. The inhibitory effect is greater at higher pH: 0.83 mM silica has no apparent adverse effect at pH 7.5, but leads to a 46% decrease in reaction rate at pH 8 and 90% at pH 9. This corresponds to observed trends in silica adsorption onto iron, which is low at pH 7.3 but increases at higher pH. Extending the duration of iron exposure to silica solutions also leads to a more pronounced inhibitory effect. This is in good agreement with the increase in silica coverage on the iron surface as revealed by X-ray photoelectron spectroscopy.  相似文献   
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The use of a novel motorized lens to perform segmentation of image sequences is presented in this paper. The lens has the effect of introducing small, repeating movements of the camera center so that objects appear to translate in the image by an amount that depends on the distance from the plane of focus. For a stationary scene, optical flow magnitudes are therefore directly related to three-dimensional object distance from the observer. We describe a segmentation procedure that exploits these controlled observer movements and present experimental results that demonstrate the successful extraction of objects at different depths. Potential applications of our approach include image compositing, teleconferencing, and range estimation.Received: 4 July 2002, Accepted: 16 December 2002, Published online: 23 July 2003 Correspondence to: Amy E. Bell  相似文献   
69.
This study examines the characteristics of alcohol-related crashes in wet versus dry counties in the state of Kentucky, USA and incorporates the location of driver residences through use of geographic information system (GIS) analysis. Between 1991 and 1997, 39344 alcohol-related crashes by Kentucky residents on Kentucky State roads were reported. The location of the crash and the home ZIP code from the driver's address were used to consider distance from home in the GIS. Analysis of the crash data revealed that a similar proportion of crashes in wet and dry counties are alcohol-related but that a higher proportion of dry counties residents are involved in an alcohol-related crash. However, when the distance from home variable is considered, several results suggest that dry county residents may be driving further when consuming alcohol. In part due to the rural nature of dry counties, drivers from dry counties have both alcohol-related and non-alcohol related crashes farther from their homes than residents from wet counties. Alcohol-related crashes by dry county residents in wet counties are the greatest average distance from home while crashes by wet county residents in wet counties are the smallest average distance. Drivers from dry counties over 21 years of age have alcohol-related crashes significantly farther from home than those under 21 who would not legally be admitted to drinking establishments in the wet counties. Furthermore, residents from dry counties that do not border wet counties have alcohol-related crashes on average farther from home than the border county residents. These last three results provide circumstantial evidence that some dry county drivers may be driving to wet counties to consume alcohol thus increasing impaired driving exposure. In conclusion, by considering crash location and driver residence, these findings indicate that county-level prohibition is not necessarily effective in improving highway safety.  相似文献   
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