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261.
Deborah G. Johnson 《Nanoethics》2007,1(1):21-30
After reviewing portions of the 21st Century Nanotechnology Research and Development Act that call for examination of societal and ethical issues, this essay seeks to understand how nanoethics can play a role in nanotechnology development. What can and should nanoethics aim to achieve? The focus of the essay is on the challenges of examining ethical issues with regard to a technology that is still emerging, still ‘in the making.’ The literature of science and technology studies (STS) is used to understand the nanotechnology endeavor in a way that makes room for influence by nanoethics. The analysis emphasizes: the contingency of technology and the many actors involved in its development; a conception of technology as sociotechnical systems; and, the values infused (in a variety of ways) in technology. Nanoethicists can be among the many actors who shape the meaning and materiality of an emerging technology. Nevertheless, there are dangers that nanoethicists should try to avoid. The possibility of being co-opted from working along side nanotechnology engineers and scientists is one danger that is inseparable from trying to influence. Related but somewhat different is the danger of not asking about the worthiness of the nanotechnology enterprise as a social investment in the future. 相似文献
262.
Janean E. Dilworth‐Bart Ayesha Khurshid Deborah Lowe Vandell 《Infant and child development》2007,16(5):525-552
Using Ecological Systems Theory and stage sequential modelling procedures for detecting mediation, this study examined how early developmental contexts impact preschoolers' performances on a measure of sustained attention and impulse control. Data from 1273 European‐American and African‐American participants in the NICHD Study of Early Child Care were used to identify the potential mediators of the relation between early household income‐to‐need (INR) and 54‐month impulsivity and inattention. Exploratory analyses were also conducted to determine whether the relationships between early income, home environment, parenting stress, and the outcome variables differ for African‐American versus European‐American‐American children. We found modest support for the study hypothesis that 36‐month home environment quality mediated the INR/attention relationship. INR accounted for more home environment score variance and home environment accounted for more Impulsivity score variance for African‐American children. Home environments were related to inattention in the European‐American, but not African‐American, group. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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The relationship between behavior problems and adolescent peer relations was examined in 30 black male adolescents divided into three equal-sized groups on the basis of individual psychosocial functioning (conduct-disordered, anxious-withdrawn, well-adjusted). Groups were matched on age, IQ, and father absence. An observational method was used to evaluate dominance, conflict, affect, and social competence manifested with a friend and with a well-adjusted stranger. Conduct-disordered and anxious-withdrawn adolescents displayed less social competence and less positive affect than well-adjusted adolescents when interacting with both friends and strangers. Anxious-withdrawn adolescents evidenced more personal apprehension than their well-adjusted counterparts. All groups showed greater leadership ability, talked more, and showed less personal apprehension with friends than with strangers. The findings support the role of peer relations in the maintenance and exacerbation of adolescent psychosocial difficulties.This research was supported by funding to the Department of Psychology at Memphis State University granted through the Centers of Excellence Program of the State of Tennessee. This article is based on a master's thesis submitted by the first author to the Department of Psychology at Memphis State University. 相似文献
266.
Prospective hindsight involves generating an explanation for a future event as if it had already happened; i.e., one goes forward in time, and then looks back. In order to examine how shifts in perspective might influence people's perceptions of events, we investigated two possible factors: temporal perspective (whether an event is set in the future or past) and uncertainty (whether the event's occurrence is certain or uncertain). In the first experiment, temporal perspective showed little influence while outcome uncertainty strongly affected the nature of explanations for events. Explanations for sure events tended to be longer, to contain a higher proportion of episodic reasons, and to be expressed in past tense. Evidence from the second experiment supports the view that uncertainty mediates not the amount of time spent explaining, but rather subjects' choice of explanation type. The implications of these findings for the use of temporal perspective in decision aiding are discussed. 相似文献
267.
Effects of Expectancies and Personalized Feedback on Fat Consumption, Taste, and Preference 总被引:1,自引:0,他引:1
Deborah J. Bowen Naomi Tomoyasu Marin Anderson Maureen Carney Alan Kristal 《Journal of applied social psychology》1992,22(13):1061-1079
Previous studies have shown that people develop expectations about the taste and effects of consumed substances and that those expectations can guide future behavior, cognitions, and affect. Identifying expectancies for the taste of both low- and high-fat foods is important in determining people's reactions to changes in their diets. Study 1 was designed to determine the existence of expectancies for the taste of low-and high-fat foods and the effects of these expectations on food consumption and preference. Ninety-seven subjects tasted a bowl of ice cream and rated the taste on taste judgment forms. The fat content of the ice cream (high- versus low-fat) and the expectancy of high- versus low-fat content were independently manipulated using a balanced placebo design. Expectancy affected the consumption of ice cream under most circumstances: For women who received high-fat ice cream and for men, regardless of the ice cream received, consumption was higher when high-fat ice cream was expected than when low-fat ice cream was expected. Study 2 was designed to investigate the effects of educating individuals about the diet-cancer link on consumption and preference. Receiving information about diet and cancer, especially when the information was personalized, decreased overall consumption and reported preference. Current levels of daily fat consumption also affected laboratory consumption and preference. This study has several implications for interventions to lower dietary fat. 相似文献
268.
This paper presents two studies that explore the link between self-reported conflict management strategies and aggression. It was predicted that conflict strategies involving concern for the needs of the other would be inconsistent with aggressive behavior. On the other hand, conflict strategies that involve coercion and domination were predicted to be positively related to aggressive behavior. Studies using self-report and behavioral measures of aggression provide support for these predictions. 相似文献
269.
Stephanie M. Doane Danielle S. McNamara Walter Kintsch Peter G. Polson Deborah M. Clawson 《Memory & cognition》1992,20(4):327-343
We hypothesize that a cognitive analysis based on the construction-integration theory of comprehension (Kintsch, 1988) can predict what is difficult about generating complex composite commands in the UNIX operating system. We provide empirical support for assumptions of the Doane, Kintsch, and Polson (1989, 1990) construction-integration model for generating complex commands in UNIX. We asked users whose UNIX experience varied to produce complex UNIX commands, and then provided help prompts whenever the commands that they produced were erroneous. The help prompts were designed to assist subjects with respect to both the knowledge and the memory processes that our UNIX modeling efforts have suggested are lacking in less expert users. It appears that experts respond to different prompts than do novices. Expert performance is helped by the presentation of abstract information, whereas novice and intermediate performance is modified by presentation of concrete information. Second, while presentation of specific prompts helps less expert subjects, they do not provide sufficient information to obtain correct performance. Our analyses suggest that information about the ordering of commands is required to help the less expert with both knowledge and memory load problems in a manner consistent with skill acquisition theories. 相似文献
270.
An information tradeoff is an increased processing or utilization of information from one stimulus source at the expense of processing or utilization of information from a different source. An experiment was conducted to determine whether information tradeoffs occurred when subjects attended selectively to one of two different structural levels of naturalistic scenes. The subjects’ attentional focus was directed to either the global or local structure of a scene (i.e., the scene or an object in the scene, respectively) either before or after presentation of a scene. They then had to use the information obtained from a 100-msec exposure of the scene to choose between two forced-choice alternatives that described one of the levels. The nature of the alternatives was such that both alternatives adequately characterized one of the structural levels on the basis of physical and semantic relations within the scene. Results showed that the subjects were significantly slower and less accurate when their attentional focus and the forced-choice alternatives were at different levels of stimulus structure than when they were at the same level, providingevidence of an information tradeoffwhen different types of information from a scene were used. When processinginformation from a particular structural level, information fromtheother level either was less available or was not used efficiently. Furthermore, the information tradeoffs were more severe in the precue than in the postcue condition, indicating differences in the efficiency of the selectivity process. The results are interpreted with respect to the role of selective attention in processing complex stimuli such as naturalistic scenes. 相似文献