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111.
The authors hypothesize that depressed states evolved to minimize risk in social interactions in which individuals perceive that the ratio of their social value to others, and their social burden on others, is at a critically low level. When this ratio reaches a point where social value and social burden are approaching equivalence, the individual is in danger of exclusion from social contexts that, over the course of evolution, have been critical to fitness. Many features of depressed states can be understood in relation to mechanisms that reduce social risk in such circumstances, including (a) hyper-sensitivity to signals of social threat from others, (b) sending signals to others that reduce social risks, and (c) inhibiting risk-seeking (e.g., confident, acquisitive) behaviors. These features are discussed in terms of psychosocial and neurobiological research on depressive phenomena. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
112.
Epiphytic macroinvertebrate communities of four coastal wetlands of Green Bay, Lake Michigan were compared by taxonomic composition, feeding group composition, and environmental influences using Bray-Curtis ordination. Ordination scores from the most sheltered oligotrophic site, Portage Marsh, were distinct from the eutrophic, exposed sites located in middle and lower Green Bay— Seagull Bar, Little Tail Point, and Dead Horse Bay. Epiphyton chlorophyll a, phytoplankton chlorophyll a, and specific conductance strongly correlated to the ordination axes, indicating the trophic gradient within Green Bay was a primary environmental influence. The feeding group compositions at the sites were consistent with the type and abundance of food available. Portage Marsh is a scraper-shredder system, with macroinvertebrates feeding mainly on epiphyton and coarse particulate detritus. Dead Horse Bay and Little Tail Point are collector systems, sustained by phytoplankton and fine particulate organic matter. Seagull Bar is intermediate in trophic position along the ordination axes, but more closely resemble the latter two sites. The type and abundance of food resources available to these invertebrate communities are influenced by wave exposure, light attenuation, nutrient levels, and algae levels of the littoral and pelagial waters. Macroinvertebrate communities were sensitive to shifts in food resources, which generated shifts in trophic structure.  相似文献   
113.
Crichton  Paul 《ITNOW》2006,48(5):8-9
  相似文献   
114.
A system of analysing fire reports is described, which evaluates the success of failure of the building elements and occupants in mitigating the consequencies of ignition. To handle fire reports a method of categorising the fire growth sequence in terms of both flame and smoke spread was developed. Three tactics (ignition prevention, fire control and evacuation) which mitigate the consequencies of ignition were derived from a hierarchy of fire safety and their interrelationship was examined. The application of this analysis method to two sets of the reports of fires in health buildings was undertaken and its success validated the proposed methodology.  相似文献   
115.
A simplified formulation of the geometric stiffness matrix for plate elements is presented. In this formulation the transverse displacement is defined along the element boundary but not for the element interior as with the usual formulation. As such the formulation is particularly suitable for use with hybrid stress or discrete Kirchhoff methods which are also based on boundary approximation of the transverse displacement.

The simplicity, computational economy and accuracy obtained with the formulation compare favorably with the usual order formulation.  相似文献   

116.
Hydrogenolysis of a carbobenzyloxy group (CBz) was studied utilizing molecular hydrogen in the presence of carbon-supported palladium catalyst. It was demonstrated that the kinetics of the reaction are greatly influenced by the presence of the CO2 by-product. It was found out that the presence of CO2 determines whether the reaction is first or zero order since it causes deactivation of the catalyst via inhibition. The effect of potassium carbonate (K2CO3) and triethylamine (TEA) as additives was investigated. A considerable solvent effect was also observed that may be explained by the variation of dispersion of the catalyst from one solvent to another.  相似文献   
117.
118.
The diffusion coefficient of the cationic dye Anilana Red BL in the anionically modified polyester fiber Dilana has been calculated regarding a general diffusion-immobilization model. In the model the mobile species are distinguished from the immobilized ones. In computations of Sand's equation and experimentally determined sorption isotherm of the dye in the fiber, the rate-of-dyeing curve and the concentration profiles of the dye in the same fiber were employed. The diffusion coefficient of the mobile species of Anilana Red BL in the fiber is two orders of magnitude higher than the average diffusion coefficient obtained from Hill's equation and the apparent diffusion coefficient calculated by the Boltzmann–Matano method.  相似文献   
119.
Research findings in other countries suggest that drinking driving laws could be much better enforced even without resorting to special patrols or random checks. It has been reported that law enforcement officers apprehend or breath test only a small fraction of the potentially impaired drivers that they normally encounter on patrol. This survey of New Zealand traffic officers was designed to determine the extent to which this was the case here, and what were the major disincentives to breath testing. Traffic officer responses, obtained on an anonymous questionnaire, suggested that there were not so many missed opportunities as had been suggested by others, but that there was a great deal of variability in the number of drinking drivers detected by different officers. This was confirmed by the actual distribution of breath testing activity, which was markedly different in shape (positively skewed) compared to the distribution of traffic enforcement activities in general. Several clues from the disincentives cited on the questionaire suggested that there are major deterrents to a greater degree of alcohol enforcement activity on the part of most officers. These are discussed in terms of potential legislative changes, and in relation to the changes introduced in the 1978 Transport Act Amendment.  相似文献   
120.
Discusses telematics, a new field of behavioral research in Canada that has grown with the technical developments in which computers and telecommunications have been combined. Three domains of behavioral research reflect relationships between humans and the technology and use the evidence and methods of different areas of psychology: (1) interface studies address perception and performance questions, (2) dialog studies focus on cognitive processes, and (3) impact studies investigate social relations and how institutions and individuals are affected by telematics. Studies conducted during the past 5 yrs by the Behavioural Research and Evaluation division of the Department of Communications, Government of Canada, are described in each of these 3 domains. Behavioral research in telematics is expected to be an increasingly important activity in which psychologists may play an active part as the technology disseminates. (French abstract) (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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