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131.
Although dispositional optimism serves as a resource for psychological and physical well-being, very little research has explored how to promote child dispositional optimism within the family context. The authors evaluated paternal emotional expressiveness within the family as a mediator of the association between father's and child's dispositional optimism. Participants were 422 father (M age = 44.97 years, SD = 4.21 years)–child (M age = 11.75 years, SD = 0.77 years) dyads in South Korea. Results showed that fathers’ dispositional optimism was positively linked to their expressiveness, which in turn was positively linked to their children's dispositional optimism. No significant gender or socioeconomic status differences were found. The findings have important implications for future research and for preventive interventions. 相似文献
132.
Yu Tian Zong Xin Guo Jie Ru Shi Yu Long Bian Pi Guo Han 《The Journal of psychology》2013,147(8):529-547
AbstractThis 1-year longitudinal study examined the bidirectional mediating role of loneliness in the association between shyness and generalized pathological Internet use (GPIU) in a sample of 291 Chinese university students (143 men, mean age =?19.07?years). A fully cross-lagged panel design was used in which shyness, loneliness, and GPIU were assessed at 3 time points separated by 6-month intervals (named T1, T2, and T3). The results indicated that relationships among shyness, loneliness, and GPIU were dynamic and bidirectional. Specifically, T1 shyness positively predicted increased T2 loneliness, T2 shyness positively predicted increased T3 loneliness, and T2 loneliness positively predicted increased T3 shyness. Additionally, T1 GPIU positively predicted increased T2 loneliness, T2 GPIU positively predicted increased T3 loneliness, and T2 loneliness positively predicted increased T3 GPIU. Loneliness was found to play a bidirectional mediating role in the association between shyness and GPIU. Specifically, T1 shyness and T3 GPIU were mediated through increased loneliness at T2, and T1 GPIU and T3 shyness were mediated through increased loneliness at T2. Furthermore, relationships among shyness, loneliness, and GPIU were the same across the 2 groups, with the strength of relationships being stronger for men. 相似文献
133.
This article reviews a wide range of risk factors associated with the development of conduct problems in children, with a particular focus on the influence of time spent engaged in different types of activities. The review reveals the behavioral benefits to children and adolescents of participation in activities with physical, social, and restful properties and those that can be described as structured. Further highlighted is the need for parents and occupational therapists to be aware of children's time use and daily activity participation, and the potential for these activities to be harnessed to facilitate positive behavioral outcomes for children. 相似文献
134.
The purpose of this study was to investigate the differences of knee concentric and eccentric strength and impact related knee biomechanics between jumpers and non-jumpers during step-off landing tasks. Ten male college swimming athletes (non-jumpers) and 10 track and volleyball athletes (jumpers) were recruited to participate in two test sessions: a muscle strength testing session of concentric and eccentric extension for dominant knee joint at 60 °/s and 180 °/s and a landing testing session. The participants performed five trials of step-off landing in each of four conditions: soft and stiff landing from 0.4 m and 0.6 m landing heights. The three-dimensional kinematics and ground reaction force were recorded simultaneously during step-off landing conditions. The results showed that the jumpers had significantly greater peak knee eccentric extension and concentric flexion torques compared to the non-jumpers. No significant group effects were found for peak vertical ground reaction force and knee range of motion during landing. The jumpers had significantly greater knee contact flexion angle, maximum knee flexion angle and initial knee extension moment compared to the non-jumpers. These results suggest that these athletes adopted a favorable impact attenuation strategy that is related to the greater knee eccentric muscle strength and training. 相似文献
135.
The Multilevel Latent Class Model (MLCM) proposed by Vermunt (2003) has been shown to be an excellent framework for analyzing nested data with assumed discrete latent constructs. The nonparametric version of MLCM assumes 2 levels of discrete latent components to describe the dependency observed in data. Model selection is an important step in any statistical modeling. The task of model selection for MLCM amounts to the decision on the number of discrete latent components at both higher and lower levels and is more challenging than standard Latent Class Models. In this article, simulation studies were conducted to systematically examine the effects of sample sizes, clusters/classes distinctness, and the number of latent clusters and classes on the performance of various information criteria in recovering the true latent structure. Results of the simulation studies are summarized and presented. The final section presents the remarks and recommendations about the simultaneous decision regarding the number of latent classes and clusters when applying MLCMs to analyze empirical data. 相似文献
136.
Decision-making consists of several stages of information processing, including an anticipation stage and an outcome evaluation stage. Previous studies showed that the ventral striatum (VS) is pivotal to both stages, bridging motivation and action, and it works in concert with the ventral medial prefrontal cortex (vmPFC) and the amygdala. However, evidence concerning how the VS works together with the vmPFC and the amygdala came mainly from neuropathology and animal studies; little is known about the dynamics of this network in the functioning human brain. Here we used fMRI combined with dynamic causal modeling (DCM) to investigate the information flow along amygdalostriatal and corticostriatal pathways in a facial attractiveness guessing task. Specifically, we asked participants to guess whether a blurred photo of female face was attractive and to wait for a few seconds (“anticipation stage”) until an unblurred photo of feedback face, which was either attractive or unattractive, was presented (“outcome evaluation stage”). At the anticipation stage, the bilateral amygdala and VS showed higher activation for the “attractive” than for the “unattractive” guess. At the outcome evaluation stage, the vmPFC and the bilateral VS were more activated by feedback faces whose attractiveness was congruent with the initial guess than by incongruent faces; however, this effect was only significant for attractive faces, not for unattractive ones. DCM showed that at the anticipation stage, the choice-related information entered the amygdalostriatal pathway through the amygdala and was projected to the VS. At the evaluation stage, the outcome-related information entered the corticostriatal pathway through the vmPFC. Bidirectional connectivities existed between the vmPFC and VS, with the VS-to-vmPFC connectivity weakened by unattractive faces. These findings advanced our understanding of the reward circuitry by demonstrating the pattern of information flow along the amygdalostriatal and corticostriatal pathways at different stages of decision-making. 相似文献
137.
Cross‐situational word learning, like any statistical learning problem, involves tracking the regularities in the environment. However, the information that learners pick up from these regularities is dependent on their learning mechanism. This article investigates the role of one type of mechanism in statistical word learning: competition. Competitive mechanisms would allow learners to find the signal in noisy input and would help to explain the speed with which learners succeed in statistical learning tasks. Because cross‐situational word learning provides information at multiple scales—both within and across trials/situations—learners could implement competition at either or both of these scales. A series of four experiments demonstrate that cross‐situational learning involves competition at both levels of scale, and that these mechanisms interact to support rapid learning. The impact of both of these mechanisms is considered from the perspective of a process‐level understanding of cross‐situational learning. 相似文献
138.
O.Yu. Kontsevoi Yu. N. Gornostyrev A.J. Freeman M.I. Katsnelson A.V. Trefilov 《Philosophical Magazine Letters》2013,93(7):455-463
The nature of impurity-dislocation interactions is one of the key questions governing the strength and plasticity of solid-solution materials. To investigate the influence of impurities on the mechanical properties of intermetallic NiAl, the electronic structure and energy of NiAl with a <100>{010} edge dislocation and transition-metal impurities was calculated using the real-space tight-binding linear muffin-tin orbital method. The localized electronic states, appearing in the core of the dislocation, are found to lead to strong impurity-dislocation interactions via two mechanisms: firstly, chemical locking, due to strong hybridization between impurity electronic states and dislocation localized states; secondly, electrostatic locking, due to long-range charge oscillations caused by the electron localization in the dislocation core. The results obtained explain qualitatively why the solid-solution hardening effect in NiAl correlates with the electronic structure of impurities rather than with size misfit, as expected according to traditional views. 相似文献
139.
Abstract This Letter presents a solution of the problem of the real temperature of nanoparticles under conditions of electron microscope beam irradiation. It is shown that the average temperature of the nanoparticles (NPs) may increase to several hundred degrees depending on contact conditions with the substrate, the intensity of the beam and the size of the NPs. The temperature increases with NP size a according to the dependence: T α a2 for sufficiently small particles. 相似文献
140.
This letter presents the results of internal-friction measurements of Co 70 Fe 5 Si 15 B10 metallic glass at temperatures 400K h T h 700K and frequencies 0.01 Hz h f h 0.05Hz. It is shown that Maxwellian viscoelastic damping is predominant in this case. The nature of this damping is determined by irreversible structural relaxation. The kinetic relaxation law is derived. 相似文献