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891.
随着工作记忆缺损与各类精神疾病的关联被逐渐阐明,研究者开始关注工作记忆训练能否作为干预手段应用在精神疾病领域中。当前,在对ADHD、精神分裂症、抑郁、焦虑、成瘾障碍和自闭症患者进行的工作记忆训练中发现了训练近迁移、远迁移以及临床症状缓解的相应证据,以及直接(通过提升工作记忆能力起效)和间接(通过提升其他关联能力起效)两条效益路径。此外,一个针对精神疾病患者的有效训练范式应当就三个层面进行考察:训练的一般成分(即受训的核心加工过程),训练的疾病特异成分(例如情绪工作记忆训练);以及训练的辅助性成分(例如动机、策略、慢波睡眠等)。未来研究需要关注适用不同精神疾病的训练范式与程序,促进工作记忆训练的定制化,并且通过完善评估手段进一步澄清工作记忆训练在病患中的效益机制。  相似文献   
892.
以22篇纵向社会网络分析研究文献(30项独立样本研究,27746个被试)为对象,使用元分析技术探讨青少年偏差行为的同伴选择和同伴影响效应假设。结果发现:(1)同伴选择和同伴影响效应都显著,但同伴影响效应显著大于同伴选择效应;(2)青少年发展阶段在同伴选择和同伴影响过程中存在显著的调节效应。在同伴选择过程中,青少年早期阶段不显著,而中、晚期阶段显著;在同伴影响过程中,青少年早、中期显著,晚期阶段不显著。(3)偏差行为类型在同伴选择和同伴影响效应中的调节效应不显著。(4)网络数量在同伴影响过程中存在显著的调节效应,随着网络数量增加同伴影响效应越可能成立。结论,中晚期青少年会基于偏差行为相似性选择朋友,早中期青少年会受朋友的影响而产生偏差行为。  相似文献   
893.
In order to steer an Unmanned Aerial Vehicle (UAV) and make it follow a desired trajectory, a high level controller is needed. Depending on the control algorithm, one or more parameters have to be tuned, having their values high impact on the performance. In most of the works, these parameters are taken as constant. In this paper, we apply fuzzy logic to select the parameters of the control law and compare this approach with the tuning by constant parameters and with another adjusting method based on the kinematic analysis of the equations of the UAV. After many simulations of the quadrotor following randomly generated paths, we have proved that the fuzzy tuning law is not only a good and feasible solution, but also more general as it can be applied to any trajectory.  相似文献   
894.
Career adaptivity is the first factor in a chain of putative effects posited in the career construction theory (CCT): Adaptivity → Adaptability → Adapting  Adaptation. Hitherto, research on adaptivity has chiefly used variable-centered strategies to investigate the independent effects of adaptivity-related traits on adaptability, adapting, and adaptation averaged over all individuals constituting a sample. The present research, comprising two studies, seeks to extend this work by using person-centered analytic strategies to identify distinct profiles of adaptivity based on combinations of the Big-Five personality dimensions. We also examine the associations of profile membership with adaptability, adapting, and adaptation from the CCT perspective. Latent profile analyses revealed that a comparable 3-profile solution, comprising so-called “adaptive ready”, “ordinary”, and “rigid” adaptivity profiles, fit best in both studies using distinct measures of the Big-Five. Furthermore, across both studies, the latent subgroups were found to differ on levels of adaptability measured using two distinct instruments. Adaptability was highest in the “adaptive ready” subgroup followed by the “ordinary” and “rigid” subgroups, respectively. Finally, Study 2 showed that the adaptivity profiles differed with respect to indices of adapting (viz., organized study behaviors) and adaptation (viz., academic and career-choice satisfaction) in line with expectations from the CCT. The present findings constitute the first evidence showing that career adaptivity can be adequately represented via trait interactions. The findings also add to the empirical literature underpinning the CCT. Furthermore, this research is an informative demonstration of the utility of finite mixture analyses.  相似文献   
895.
Some environmental ethicists and economists argue that attributing infinite value to the environment is a good way to represent an absolute obligation to protect it. Others argue against modelling the value of the environment in this way: the assignment of infinite value leads to immense technical and philosophical difficulties that undermine the environmentalist project. First, there is a problem of discrimination: saving a large region of habitat is better than saving a small region; yet if both outcomes have infinite value, then decision theory prescribes indifference. Second, there is a problem of swamping probabilities: an act with a small but positive probability of saving an endangered species appears to be on par with an act that has a high probability of achieving this outcome, since both have infinite expected value. Our paper shows that a relative (rather than absolute) concept of infinite value can be meaningfully defined, and provides a good model for securing the priority of the natural environment while avoiding the failures noted by sceptics about infinite value. Our claim is not that the relative infinity utility model gets every detail correct, but rather that it provides a rigorous philosophical framework for thinking about decisions affecting the environment.  相似文献   
896.
897.
Stability or sensitivity analysis is an important topic in data analysis that has received little attention in the application of multidimensional scaling (MDS), for which the only available approaches are given in terms of a coordinate‐based analytical jackknife methodology. Although in MDS the prime interest is in assessing the stability of the points in the configuration, this methodology may be influenced by imprecisions resulting from the inherently necessary Procrustes method. This paper proposes an analytical distance‐based jackknife procedure to study stability and cross‐validation in MDS in terms of the jackknife distances, which is not influenced by the Procrustes method. For each object, the corresponding jackknife estimated points are considered as naturally clustered points, and stability and cross‐validation are analysed in terms of the MDS distances arising from the jackknife procedure, on the basis of a weighted cluster‐MDS algorithm. A jackknife‐relevant configuration is also proposed for cross‐validation in terms of coordinates, in a cluster‐MDS framework.  相似文献   
898.
Subgroup analyses allow us to examine the influence of a categorical moderator on the effect size in meta‐analysis. We conducted a simulation study using a dichotomous moderator, and compared the impact of pooled versus separate estimates of the residual between‐studies variance on the statistical performance of the Q B (P) and Q B (S) tests for subgroup analyses assuming a mixed‐effects model. Our results suggested that similar performance can be expected as long as there are at least 20 studies and these are approximately balanced across categories. Conversely, when subgroups were unbalanced, the practical consequences of having heterogeneous residual between‐studies variances were more evident, with both tests leading to the wrong statistical conclusion more often than in the conditions with balanced subgroups. A pooled estimate should be preferred for most scenarios, unless the residual between‐studies variances are clearly different and there are enough studies in each category to obtain precise separate estimates.  相似文献   
899.
Previous research has suggested that problematic Internet use (PIU) is associated with impulse control disorder. Although researchers have suggested that impulsivity is a risk factor for PIU, the literature lacks longitudinal evidence on the relationship between impulsivity and PIU. We aimed to use a cross‐lagged analytic framework to identify temporal order effects and hypothesised that impulsivity was the precedent factor for PIU. In a panel sample of college students (N = 367), trait impulsivity and PIU were measured in the spring of freshman year and in their junior year. The measures included a self‐developed PIU Scale and the revised Impulsiveness Scale based on Barratt's concept. We found that “non‐planning impulsivity” was not associated with PIU. The “motor impulsivity” subfactor was thus adopted in the cross‐lagged model. The results suggest that motor impulsivity and PIU were stable across time. Motor impulsivity at Time 1 positively predicted PIU at Time 2, but PIU at Time 1 did not predict motor impulsivity at Time 2. A further investigation using gender as a moderator found a gender difference in the temporal relationship. Because motor impulsivity is a risk factor for PIU, potential prevention strategies based on this result are suggested.  相似文献   
900.
While economic downturns have adverse effects on young people's life chances, empirical studies examining whether and to what extent human values, social attitudes and well‐being indicators respond to sudden economic shocks are scarce. To assess the claim that human values are less affected by economic shocks than social attitudes and well‐being, two distinct yet related studies based on the European Social Survey (ESS) are conducted. The first employs a fixed effects pseudo‐panel analysis of the 2008–2014 ESS‐waves to detect whether changes over time in the socio‐demographic group's unemployment risk and national youth unemployment affect individual dispositions to varying degrees. The second study captures micro‐ and cross‐national effects in the 2010 ESS cross‐section. Unique for this set‐up is that we can test whether the findings hold for over‐time changes in youth unemployment within countries (pseudo‐panel), as well as for cross‐country differences in youth unemployment (multilevel). Both studies indicate that political trust, satisfaction with the economy and subjective well‐being are lowered by economic risk and hardship, while social trust and self‐rated health are less affected by changes in youth unemployment. Secondly, human values are immune to economic risk, underscoring that values transcend specific situations and are therefore resistant against sudden economic shocks.  相似文献   
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