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161.
We examine the association between neighborhood socio-economic disadvantage and perceived stress during middle and late adolescence among African American youth (N = 665; 51 % female; M = 15.9 years at baseline). In addition, we explored the ways through which neighborhood stressors interacted with an individual’s intra- and interpersonal resources (e.g., coping, social support and substance use), to affect their perceived stress trajectories during adolescence. First, we tested a neighborhood stressors model and found that youth who lived in neighborhoods with greater socioeconomic disadvantage had higher baseline stress and a steeper increase in stress over time. When we included individual-level risk and promotive factors in the model, however, the effect of neighborhood disadvantage on perceived stress was no longer significant, and the stress trajectory was explained by adolescent substance use, social support and perceptions of the neighborhood. Our results support theories of stress and coping, and the importance of proximal intra- and interpersonal factors in either amplifying or mitigating perceptions of stress. We discuss implications of the neighborhood context and how our findings may inform future prevention and intervention related to adolescent stress and development.  相似文献   
162.
In two experiments, 18-month-old infants’ categorization of 3D replicas and 2D photographs of the same animals and vehicles were compared to explore infants’ flexibility in categorization across different object representations. Using a sequential touching procedure, infants completed one superordinate and two basic-level categorization tasks with 3D replicas, 2D cut out photographs, or 2D images on photo cubes (“2D cubes”). For superordinate sets, 3D replicas elicited longer mean run lengths than 2D cut outs, and 3D replicas elicited equivalent mean run lengths as 2D cubes. For basic-level sets, infants categorized high-contrast animal sets when presented with 3D replicas, but they failed to categorize any of the 2D photograph sets. Categorization processes appear to differ for 3D and 2D stimuli, and infants’ discovery of object properties over time while manipulating objects may facilitate categorization, as least at the superordinate level. These findings are discussed in the context of infants’ representation abilities and the integration of perception and action.  相似文献   
163.
164.
Most health decision-making models posit that cost-benefit analyses underlie decisions to make changes in health-related behavioral practices. In a series of studies, participants imagined either increasing or decreasing the frequency of a variety of health behaviors and estimated the consequences of those changes. In Studies 1 and 2, individuals consistently estimated that increasing a health behavior produced greater consequences than did decreasing the behavior by an equivalent amount. The results of Study 3 demonstrated that this effect is due to differences in how individuals judge the impact of health behavior changes which involve not engaging in the behavior at all versus other types of changes. Taken together, these findings suggest that perceptions of the outcomes afforded by health behavior changes depend on both the behavioral frequency and direction of changes in behavior an individual is considering. This asymmetry has the potential to help explain patterns of behavior in a range of important health domains and may impact the effectiveness of behavior change interventions.  相似文献   
165.

Microstructural investigations have been carried out on a fully lamellar Ti49Al47Cr2Nb2  相似文献   
166.
Through action-research case study in the area of “Parks and Gardens”, this paper focused on the relations between “aloneness”, “loneliness” and “solitude” at work and their necessary distinctions. The Socio-Clinical work psychology approach used during the intervention helped to highlight some key elements. While aloneness characterizes a stretched between the subject and its external environment link, loneliness and solitude are defined as intra-subjective process mainly emotional psycho. These last notions remain in any case a test for physical and psychological occupational health. It seems that the outcomes depend largely on the ability of the subject to convert aloneness to solitude. In our case study three valences of aloneness with different level of risk for health, were underline: solitude, as creative aloneness; defensive aloneness; and loneliness. The advantages of this new approach for prevention are discussed in the positioning relative to other work on the subject.  相似文献   
167.
The introduction of multi-voxel pattern analysis (MVPA) to the functional magnetic resonance imaging (fMRI) community has brought a deeper appreciation for the diverse forms of information that can be present within fMRI activity. The conclusions drawn from MVPA investigations are frequently influenced by both the ability to decode information from multi-voxel patterns and mean activation levels. In practice, MVPA studies vary widely in why and how they test for differing overall response levels. In this article, I examine the place of univariate information in MVPA investigations. I first discuss the variety of interpretations given to finding univariate response differences. I go on to discuss some of the analysis approaches used to investigate and compare univariate and multivariate sources of information, which can illuminate their respective contributions. It will be important for the MVPA and general fMRI community to continue to discuss and debate these important issues.  相似文献   
168.
Pupil dilation is a useful, noninvasive technique for measuring the change in cognitive load. Since it is implicit and nonverbal, it is particularly useful with preverbal or nonverbal participants. In cognitive psychology, pupil dilation is most often measured by corneal reflection eye-tracking devices. The present study investigates the effect of gaze position on pupil size estimation by three common eye-tracking systems. The task consisted of a simple object pursuit situation, as a sphere rotated around the display screen. Systematic errors of pupil size estimation were found with all three systems. Implications for task-elicited pupillometry, especially for gaze-contingent studies such as object tracking or reading, are discussed.  相似文献   
169.
Referral of patients with endometrial (EC) and/or ovarian cancer (OC) for genetic counseling is based on age at diagnosis and family history. Many patients with hereditary cancers are missed by following this strategy. We determined acceptance and mutation detection rate of offering genetic counseling and testing to unselected EC and OC patients. Therefore, in 2007, EC and OC patients were invited for genetic counseling and testing. Patients were asked for their reasons to accept or decline. Nineteen out of fifty-two EC patients (36 %) and twenty-two out of thirty-five OC patients (63 %) accepted genetic counseling, mainly to receive risk assessment for themselves and relatives. Counseling was declined mainly because patients did not want more tests or had no relatives for whom it was relevant. Eighteen out of nineteen EC patients (95 %) and twenty out of twenty-two OC patients (91 %) underwent genetic testing. One EC patient carried an MSH6 mutation (mutation detection rate: 6 %). BRCA1/2 mutations were found in two out of twenty OC patients (10 %). Eleven patients (29 %) received surveillance recommendations for themselves and their relatives. Finally, family history recorded by the gynecologist was compared to that taken by the clinical geneticist. Gynecologists reported family history in ten out of forty-one participants (24 %). In conclusion, genetic counseling and testing are acceptable to patients with OC and/or EC. The 10 % BRCA1/2 mutation detection rate and underreporting of family history by gynecologists warrant referral for genetic counseling for all OC patients, followed by BRCA1/2 testing if indicated. We recommend that microsatellite instability and immunohistochemical analysis be performed in all EC patients, followed by genetic counseling if appropriate. These strategies will lead to better cancer prevention in gynecological cancer patients and their relatives.  相似文献   
170.
The recently proposed action-concept view of perceptual-motor behaviour posits that a stimulus which consistently follows a certain response will become associated with that response. Some evidence in favour of this view comes from the finding that the size of the Simon effect can be altered by the inclusion of post-response stimuli. However, only one study has investigated the effects of including same-side in addition to opposite-side post-response stimuli, as well as a neutral Simon condition, and, possibly because of a failure of random assignment, the results from that study were inconclusive. In light of this limitation, a Simon experiment was performed in which the location of post-response stimulation was manipulated within subjects. The results showed that: (1) the Simon effect can both decrease and increase in the presence of post-response stimuli, and (2) the amounts of Simon interference and Simon facilitation are both affected by post-response stimuli, whereas performance on neutral trials is not. These findings provide additional support for the action-concept view and suggest that further research concerning this new approach is warranted.  相似文献   
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