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71.
The present study aimed to integrate the social identity approach to health and well-being with social network analysis. Previous research on the effects of social network centrality on stress has yielded mixed results. Building on the social identity approach, we argued that these mixed results can be explained, in part, by taking into account the degree to which individuals identify with the social network. We hence hypothesized that the effects of social network centrality on stress are moderated by social identification. Using a full roster method, we assessed the social network of first-year psychology students right after the start of their study programme and three months later. The effects of network centrality (betweenness, closeness, eigenvector centrality) and social identification on stress were examined using structural equation models. As predicted, our results revealed a significant interaction between network centrality and social identification on stress: For weakly or moderately identified students, network centrality was positively related to stress. By contrast, for strongly identified students, network centrality was unrelated to stress. In conclusion, our results point to the perils of being well-connected yet not feeling like one belongs to a group.  相似文献   
72.
Using Louis’ formula, it is possible to obtain the observed information matrix and the corresponding large-sample standard error estimates after the expectation–maximization (EM) algorithm has converged. However, Louis’ formula is commonly de-emphasized due to its relatively complex integration representation, particularly when studying latent variable models. This paper provides a holistic overview that demonstrates how Louis’ formula can be applied efficiently to item response theory (IRT) models and other popular latent variable models, such as cognitive diagnostic models (CDMs). After presenting the algebraic components required for Louis’ formula, two real data analyses, with accompanying numerical illustrations, are presented. Next, a Monte Carlo simulation is presented to compare the computational efficiency of Louis’ formula with previously existing methods. Results from these presentations suggest that Louis’ formula should be adopted as a standard method when computing the observed information matrix for IRT models and CDMs fitted with the EM algorithm due to its computational efficiency and flexibility.  相似文献   
73.
This study assessed relations between exposure to trauma and post-traumatic stress (PTS) symptoms, and whether perceived social support from family and friends and gender moderated these associations. Syrian refugee youth (N = 418, 55.0% female) attending public schools in Jordan participated. Boys reported more age-adjusted PTS symptoms than girls. Analyses revealed that family support and gender moderated the association of trauma on PTS symptoms. For males, the benefits of family support were most evident under conditions of high traumatic stress exposure, while for females, benefits of family support were evident when no loss or injury to family members had been reported. Support from friends was not helpful for either gender. School- or family-based interventions designed to treat PTS symptoms need to consider the different needs of boys and girls, particularly within the Syrian Muslim cultural context.  相似文献   
74.
Schools have a significant effect on students' development, and serve as important social agencies for interventions for students facing disasters. However, little is known about the effect of students' school experience itself on their resilience when facing extreme negative events. The present study focused on students who were exposed to terror-related homicide with the aim of investigating the contribution of school climate resources to their resilience. Since resilience is associated not only with fewer negative outcomes, but also with positive change, the contribution of schools was studied as both inhibiting post-traumatic stress symptoms (PTS) and enhancing post-traumatic growth (PTG). A mixed-methods research design was used. The participants included 117 (52% girls) high school students (mean age = 14.54; SD = 1.49). Twenty-five of them were interviewed in addition to responding to the research questionnaires. Different aspects of the school climate were found to be associated with students' PTS and PTG, yielding two overarched factors explaining the school's role as a protective resource: sheltering and supporting. The former is associated with fewer PTS and the latter with higher PTG. The use of different resources for different forms of resilience is discussed.  相似文献   
75.
PurposeThe purpose of this study was to investigate resting autonomic activity in adults who stutter (AWS) compared to adults who do not stutter (ANS) and the relationship this has on self-reports of social anxiety.MethodsThirteen AWS and 15 ANS completed the Social Interaction Anxiety Scale (SIAS; Mattick & Clark, 1998) and Brief Fear of Negative Evaluation (BFNE; Leary, 1983). Following this, measures of skin conductance levels (i.e. index of sympathetic activity) and respiratory sinus arrhythmia (i.e. index of parasympathetic activity) were taken during a 5-minute resting, baseline period. Independent sample t tests were used to assess differences between groups on self-reports of anxiety (SIAS, BFNE) and resting autonomic levels (SCL, RSA). Separate multiple regression analyses were performed in order to assess the relationship between self-reports of anxiety and autonomic measures.ResultsResults showed significantly higher mean SCL and lower mean RSA levels in the AWS compared to the ANS at resting, baseline. Regression analysis showed that self-reports from the SIAS had a significant effect on RSA levels for the AWS but not the ANS. No significant effects were found for BFNE on RSA. Nor was there a significant effect from SIAS or BFNE on SCL levels for either group.ConclusionFindings suggest that resting RSA levels may be a physiological marker for social anxiety levels in adults who stutter.  相似文献   
76.
《Psychologie Fran?aise》2021,66(4):345-356
Posttraumatic stress disorder (PTSD) is estimated to remain chronic and severe for 25–50% of patients despite psychotherapeutic treatment. Part of the reasons is that patients with PTSD can have difficulties in establishing a good therapeutical alliance with the therapist. Moreover, they often fail to re-think the content of the trauma without being overwhelmed by negative emotions and tend to rely on avoidance strategies and/or to abandon the therapy. MDMA (“ecstasy”) is a drug classified as an entactogen (en “within”, tactus “touch”, and gen “produce”), an amphetamine with psychedelic properties that possesses psychopharmacological properties to overcome these issues. Indeed, MDMA triggers the release of oxytocin, which favors the establishment of interpersonal relationship based on kindness and trust. Moreover, MDMA diminishes the activity of the amygdale, allowing patients to work on challenging memories with less fear and anxiety. Finally, MDMA may also provide access to meaningful spiritual experiences, release of tensions and a sense of healing on a non-verbal level that are not completely understood. But are viewed as important by patients. Today, there is no evidence that the use of MDMA in a clinical setting has bad neurologic, psychological or cognitive consequences. Results of phase II trials in the United States and Europe confirm that MDMA favors psychotherapy's outcome without severe adverse effects. Phase III trials are underway. The Multidisciplinary Association for Psychedelic Studies (MAPS) has published online a method proposal and trains therapists in MDMA-assisted psychotherapy.ConclusionFood and Drug Administration (FDA) and European Medicines Agency (EMA) could approve this therapeutic tool in the coming years.  相似文献   
77.
Perceptual judgments result from a dynamic process, but little is known about the dynamics of number-line estimation. A recent study proposed a computational model that combined a model of trial-to-trial changes with a model for the internal scaling of discrete numbers. Here, we tested a surprising prediction of the model—a situation in which children's estimates of numerosity would be better than those of adults. Consistent with the model simulations, task contexts led to a clear developmental reversal: children made more adult-like, linear estimates when to-be-estimated numbers were descending over trials (i.e., backward condition), whereas adults became more like children with logarithmic estimates when numbers were ascending (i.e., forward condition). In addition, adults’ estimates were subject to inter-trial differences regardless of stimulus order. In contrast, children were not able to use the trial-to-trial dynamics unless stimuli varied systematically, indicating the limited cognitive capacity for dynamic updates. Together, the model adequately predicts both developmental and trial-to-trial changes in number-line tasks.  相似文献   
78.
The unprecedented effects and duration of the COVID-19 crisis are likely to elevate the population’s level of anxiety due to psychological stress, economic hardship, and social isolation. This effect may be especially potent for individuals with preexisting mental health conditions, such as posttraumatic stress disorder (PTSD). Prolonged Exposure (PE) therapy is a highly effective treatment for PTSD across trauma-exposed populations, and has been implemented effectively via telehealth. Nevertheless, PE implementation via telehealth may require specific adaptations during the COVID-19 crisis due to public health mandates calling for sheltering in place and physical distancing. This paper discusses strategies for implementing PE for PTSD during the COVID-19 pandemic, which may also be applied to other situations in which physical distancing must be considered.  相似文献   
79.
Traffic congestion and crash rates can be reduced by introducing variable speed limits (VSLs) and automatic incident detection (AID) systems. Previous findings based on loop detector measurements have revealed that drivers reduce their speeds while approaching traffic congestion when the AID system is active. Notwithstanding these behavioural effects, most microscopic traffic flow models assessing the impact of VSLs do not describe driver response accurately.This study analyses the main factors that influence driver deceleration behaviour while approaching traffic congestion with and without VSLs. The Dutch VSL database was linked to the driver behaviour data collected in the UDRIVE naturalistic driving study. Driver engagement in secondary tasks and glance behaviour were extracted from the video data. Linear mixed-effects models predicting the characteristics of deceleration events were estimated.The results show that the maximum deceleration is high when approaching a slower leader, when driving at high speeds and short distance headways, and close to the beginning of traffic congestion. The minimum time headway is short when driving at high speeds and changing lanes. Certain drivers showed higher decelerations and shorter time headways than others. Controlled for these main factors, smaller maximum decelerations were found when the VSLs were present and visible, and when the gantries were within close proximity. These factors could be incorporated into microscopic traffic simulations to evaluate the impact of AID systems on traffic congestion more realistically. Further research is needed to clarify the link between engagement in secondary tasks, glance behaviour and deceleration behaviour.  相似文献   
80.
Autonomous Vehicle (AV) research has focused on public acceptance of and intention to use AVs, with trust emerging as important to these variables. Research on AV trust has centered on trust in vehicle performance. However, trust evaluation may include AV manufacturers and developers, and regulation pertaining to AVs; thus, we expand our measurement of trust to include beliefs based on manufacturers and regulation. In this experiment, we manipulate information regarding manufacturer focus (i.e., an emphasis on standards, regulations, and research (SRR) versus speed to market) to determine its effect on trust. When information focused on SRR, we found higher levels of trust in AV performance and in manufacturers, compared to when it focused on speed to market. In addition, information regarding passenger control (i.e., the ability to take over for the vehicle and to determine privacy settings) was manipulated to yield either high or low passenger control conditions. Behavioral Intention (BI) to use AVs was lowest when speed to market was emphasized and when passenger control was low. Furthermore, trust was tested as a mediator between perceived risk and BI. Trust in AV performance partially mediated the relationship between perceived AV performance risk and BI. In addition, trust in AV regulation partially mediated the relationship between AV privacy/security risk and BI. Researchers should continue to examine trust beyond the AV itself to encompass trust in manufacturers and regulations. Those designing and marketing AVs should carefully consider decisions that influence manufacturer/developer reputation and passenger control due to their effect on intention to use AVs.  相似文献   
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