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41.
A new contraceptive technology may advance the science of family planning but may do little to affect health if potential users do not deem it an acceptable method. The authors conducted an acceptability study of a newly developed contraceptive method--personal hormone monitoring. A sample of 480 English volunteers present at the 6th month of a 13-month longitudinal study completed surveys regarding their attitudes toward a personal hormone monitor for the purpose of contraception. The authors used the participants' responses to determine (a) the extent to which the participants accepted the monitor, (b) how their ratings of acceptability changed over time, (c) the extent to which contextual variables predicted changes in acceptability over time, and (d) whether those contextual variables predicted final acceptability of the monitor. Results suggested that no single method of family planning is best for everyone and specified the people for whom personal hormone monitoring may be most suitable. 相似文献
42.
Crown CL Feldstein S Jasnow MD Beebe B Jaffe J 《Journal of psycholinguistic research》2002,31(1):1-23
The purpose of this study was to examine the hypothesis that 6-week-old infants are capable of coordinated interpersonal timing within social interactions. Coordinated interpersonal timing refers to changes in the timing of one individual's behavior as a function of the timing of another individual's behavior. Each of 45, first-born 6-week-old infants interacted with his or her mother and a stranger for a total of 14 minutes. The interactions were videotaped and coded for the gaze behavior of the infants and the vocal behavior of the mothers and strangers. Time-series regression analyses were used to assess the extent to which the timing of each of the infants' gazes was coordinated with the timing of the adults' vocal behavior. The results revealed that (a) coordinated timing occurs between infants and their mothers and between infants and strangers as early as when infants are 6 weeks old, and (b) strangers coordinated the timing of their pauses with the infants to a greater extent than did mothers. The findings are discussed in terms of the role of temporal sensitivity in social interaction. 相似文献
43.
Experiment 1 showed that laboratory-reared desert kangaroo rats, like domestic Norway rats, efficiently search for food on a radial arm maze (RAM) by avoiding revisiting arms within a trial. By placing an RAM on the floor so the animals could approach food from any direction, Experiment 2 tested whether efficient search by kangaroo rats was based on tactics of distance minimizing, central-place foraging, trail following, or meandering. In contrast to the dominant trail-following tactic of domestic Norway rats (Hoffman, Timberlake, Leffel, & Gont, 1999), kangaroo rats tended to distance minimize, whether maze arms were present or not. Experiment 3 indicated that kangaroo rats treated a floor configuration of eight food cups as two patches of four, based on beeline travel between patches and meandering within them. We conclude that similar performance in an elevated RAM by different species can be based on different tactics, and we suggest that a laboratory apparatus can be used to cast light on niche-related mechanisms. 相似文献
44.
Grossman M Cooke A DeVita C Chen W Moore P Detre J Alsop D Gee J 《Brain and language》2002,80(3):296-313
We used fMRI to examine patterns of brain recruitment in 22 healthy seniors, half of whom had selective comprehension difficulty for grammatically complex sentences. We found significantly reduced recruitment of left posterolateral temporal [Brodmann area (BA) 22/21] and left inferior frontal (BA 44/6) cortex in poor comprehenders compared to the healthy seniors with good sentence comprehension, cortical regions previously associated with language comprehension and verbal working memory, respectively. The poor comprehenders demonstrated increased activation of left prefrontal (BA 9/46), right dorsal inferior frontal (BA 44/6), and left posterior cingulate (BA 31/23) cortices for the grammatically simpler sentences that they understood. We hypothesize that these brain regions support an alternate, nongrammatical strategy for processing complex configurations of symbolic information. Moreover, these observations emphasize the crucial role of the left perisylvian network for grammatically guided sentence processing in subjects with good comprehension. 相似文献
45.
A blind man (E.A.) was asked to draw pictures suggesting wheels in various kinds of motion. Six pictures were drawn by E.A. The pictures were shown to sighted subjects, who were asked to assign labels to the pictures, in a multiple-choice format. The labels were assigned at a rate above chance. We argue that the pictures are metaphoric and that pictorial metaphor relies on common properties of the static picture and the kinetic referent. 相似文献
46.
Comparing contrast-modulated and luminance-modulated masking: effects of spatial frequency and phase
The masking of a sinusoidal test grating by contrast-modulated (CM) gratings could, in principle, be attributable to the presence of a distortion product, injected into the stimulus during some nonlinear transformation at an early level of visual processing (e.g. Nachmias, 1989 Vision Research 29 137-142). If so, CM gratings and luminance-modulated (LM) gratings of similar effective contrast and spatial frequency should mask the detection of sinusoids in a similar fashion. We compared the effects of masking by 1 cycle deg-1 CM gratings [both simple beats (8 + 9 cycles deg-1) and amplitude-modulated gratings (8 + 9 + 10 cycles deg-1)], with those of masking by 1 cycle deg-1 LM gratings of low contrast. We found that: (i) CM and low-contrast LM grating masks yielded similar spatial-frequency tuning functions around the modulation frequency of 1 cycle deg-1; (ii) low-contrast LM gratings masked the detection of test sinusoids in a highly phase-dependent fashion, while masking by CM gratings did not vary systematically with relative spatial phase. The results suggest that masking produced by CM gratings cannot simply be explained by the presence of a distortion product at the beat or modulation frequency. 相似文献
47.
48.
Two notions strongly held by many smokers are that negative mood increases smoking behavior and that this increase is due to the ability of smoking to alleviate negative affect. This study used a modified mood induction procedure to examine both the impact of smoking on induced mood, as well as the effect of induced mood on actual smoking behavior. Forty-eight smokers were randomly assigned to a smoking or a water-drinking comparison group. Each participant attended 3 sessions during which 1 of 3 mood states (positive, negative, or neutral) was induced. Contrary to expectation, smoking did not attenuate negative affect. However, negative mood induction subsequently quickened latency to smoke and increased number of puffs consumed ad lib. 相似文献
49.
The Brief Fear of Negative Evaluation Scale (BFNE; M. R. Leary, 1983a) is often used to assess fear of negative evaluation, the core feature of social anxiety disorder. However, few studies have examined its psychometric properties in large samples of socially anxious patients. Although the BFNE yields a single total score, confirmatory factor analysis indicated a 2-factor solution to be more appropriate, with the 1st factor consisting of all straightforwardly worded items (BFNE-S) and the 2nd of all reverse-scored items (BFNE-R). Support was obtained for the convergent and discriminant validity of the BFNE and BFNE-S, but not the BFNE-R. These results suggest that standard scoring of the BFNE may not be optimal for patients with social anxiety disorder. 相似文献
50.
Developing human-nonhuman chimeras in human stem cell research: ethical issues and boundaries 总被引:1,自引:0,他引:1
The transplantation of adult human neural stem cells into prenatal non-humans offers an avenue for studying human neural cell development without direct use of human embryos. However, such experiments raise significant ethical concerns about mixing human and nonhuman materials in ways that could result in the development of human-nonhuman chimeras. This paper examines four arguments against such research, the moral taboo, species integrity, "unnaturalness," and human dignity arguments, and finds the last plausible. It argues that the transfer of human brain or retinal stem cells to nonhuman embryos would not result in the development of human-nonhuman chimeras that denigrate human dignity, provided such stem cells are dissociated. The article provides guidelines that set ethical boundaries for conducting such research that are consonant with the requirements of human dignity. 相似文献