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21.

It has become increasingly common for young children to be taken care of by multiple caregivers in China after the socio-economic reforms. Complex migration patterns and high female labour force participation have led to children receiving care from various individuals in different contexts. However, little is known about how childcare arrangements are associated with child health well-being. This study examines various early childhood caregivers and their influences on children’s physical health in China. Using data from the China Health and Nutrition Survey (CHNS 1991–2011) with 3,470 children aged 2 to 6, we first identified different types of childcare arrangements in and outside of the household based on who provides the care, where they provide the care, and the intensity of the care. Then we examined the relationship between various childcare arrangements and health outcomes for children. Overall, household members undertook early childhood care tasks in China, with an increase in grandparents as primary caregivers between 1991 and 2011. The proportion of children receiving formal childcare fluctuated around 20% during this period. The findings suggest that: 1) primary caregiver in the household other than parents is not associated with undesirable physical health outcomes; 2) formal childcare outside the household is associated with higher height and lower BMI scores; 3) primary caregivers in the household, particular grandparents, moderate the association between childcare arrangements outside the household and children’s health outcomes. It yields an implication that early childhood care policies incorporating multiple caregivers would benefit children’s well-being in China.

  相似文献   
22.
A robust vision-based staircase identification method is proposed, which comprises 2D staircase detection and 3D staircase localization. The 2D detector pre-screens the input image, and the 3D localization algorithm continues the task of retrieving geometry of the staircase on the reported region in the image. A novel set of principal component analysis-based Haar-like features are introduced, which extends the classical Haar-like features from local to global domain and are extremely efficient at rejecting non-object regions for the early stages of the cascade, and the Viola–Jones rapid object detection framework is improved to adapt the context of staircase detection, modifications have been made on the scanning scheme, multiple detections integrating scheme and the final detection evaluation metrics. The V-disparity concept is applied to detect the planar regions on the staircase surface and locate 3D planes quickly from disparity maps, and then, the 3D position of staircase is localized robustly. Finally, experiments show the performance of the proposed method.  相似文献   
23.
Previous studies have shown that adults who stutter produce smaller corrective motor responses to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for online speech monitoring. In this study, we examined whether stuttering is also associated with deficiencies in integrating and using discrepancies between expected and received auditory feedback to adaptively update motor programs for accurate speech production. Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering controls. We found that the magnitude of the speech adaptive response for children who stutter did not differ from that of fluent children. However, the adaptation magnitude of adults who stutter in response to auditory perturbation was significantly smaller than the adaptation magnitude of adults who do not stutter. Together these results indicate that stuttering is associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory‐motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering.  相似文献   
24.
采用事件相关电位技术,考察内隐多效性选择及其神经机制。被试的任务是认真观看配对的纯色图片刺激,并进行分类按键反应。实验结果发现,在P2上,积极启动刺激比对照刺激激发了更大的P2波幅; 对比对照刺激,积极启动刺激在左脑、大脑中部和后脑诱发了更大的P2波幅,其中右脑的效应最大。在N2上,积极启动刺激比对照刺激激发了更小的N2波幅; 对比对照刺激,积极启动刺激在左脑、大脑中部和后脑诱发了更小的N2波幅,其中右脑的效应最大。在P3上,积极启动刺激比对照刺激激发了更大的P3波幅; 对比对照刺激,积极启动刺激在左脑、大脑中部和后脑诱发了更大的P3波幅,其中右脑的效应最大。研究结果表明当外显目标与内隐目标同时被呈现时,被试趋向于做多效性选择,这可能表明无意识信息加工具有相当大的权重。且右后部脑区可能是加工多效性刺激的核心和关键区域,P3成分可能反应了内隐多效性选择的精细加工过程,能够作为内隐多效性选择的有效的ERPs指标。  相似文献   
25.
通过操纵反馈时间(即时,延迟)、反馈类型(简单,丰富)和掩蔽类型(塔罗牌,空白矩形),考察概率类别学习的学习机制。结果发现:(1)被试的学习成绩在即时反馈条件下显著优于在延迟反馈条件下;(2)在即时反馈条件下,仅给予简单反馈,被试虽能出色地完成天气预报任务,但是不能正确地判断卡片预测晴天的概率,倾向内隐学习;(3)在其他条件下,被试能正确地判断卡片预测晴天的概率以及各卡片在天气预报任务中预测天气的重要程度,表明被试能外显地意识到这些线索的作用。综上,概率类别学习采用的是双系统学习机制,既依赖内隐学习,又依赖外显学习。  相似文献   
26.
Background and Objectives: Prior studies have found that the serotonin transporter gene-linked polymorphic region (5-HTTLPR) interacts with trauma exposure to increase general risk for Posttraumatic Stress Disorder (PTSD). However, there is little knowledge about the effects of the interaction on distinct symptom clusters of PTSD. This study aimed to investigate the relation between the interaction of 5-HTTLPR and earthquake-related exposures and a contemporary phenotypic model of DSM-5 PTSD symptoms in a traumatised adult sample from China.

Design: A cross-sectional design with gene-environment interaction (G?×?E) approach was adopted. Methods: Participants were 1131 survivors who experienced 2008 Wenchuan earthquake. PTSD symptoms were assessed with the PTSD Checklist for DSM-5 (PCL-5). The 5-HTTLPR polymorphism was genotyped with capillary electrophoresis (CE) in ABI 3730xl genetic Analyzer.

Results: Although there was no significant interaction between 5-HTTLPR and traumatic exposure on total PTSD symptoms, respondents with the LL genotype of 5-HTTLPR who were highly exposed to the earthquake experienced lower intrusion and avoidance symptoms than those with the S-allele carriers.

Conclusions: The findings suggest that the 5-HTTLPR may have an important impact on the development of PTSD and add to the extant knowledge on understanding and treating of posttraumatic psychopathology.  相似文献   
27.
This paper examines critically the notion of reflection as self-objectification and points out its insufficiency in accounting for the pathological phenomenon of hyperreflexivity. It proposes an understanding of reflection as situated and motivated from within a world and having a normative aspect that concerns the very life of the reflecting person. On this account, the paper argues, on the one hand, that both phenomenological reflection and hyperreflexivity can be viewed as forms of reflection characterized by loss of the world. On the other hand, by construing the phenomenological loss as imaginative vis-à-vis the real loss of hyperreflexivity, the paper emphasizes a difference between the two domains.  相似文献   
28.
29.
For comparing nested covariance structure models, the standard procedure is the likelihood ratio test of the difference in fit, where the null hypothesis is that the models fit identically in the population. A procedure for determining statistical power of this test is presented where effect size is based on a specified difference in overall fit of the models. A modification of the standard null hypothesis of zero difference in fit is proposed allowing for testing an interval hypothesis that the difference in fit between models is small, rather than zero. These developments are combined yielding a procedure for estimating power of a test of a null hypothesis of small difference in fit versus an alternative hypothesis of larger difference.  相似文献   
30.
Structural equation models (SEMs) have become widely used to determine the interrelationships between latent and observed variables in social, psychological, and behavioural sciences. As heterogeneous data are very common in practical research in these fields, the analysis of mixture models has received a lot of attention in the literature. An important issue in the analysis of mixture SEMs is the presence of missing data, in particular of data missing with a non‐ignorable mechanism. However, only a limited amount of work has been done in analysing mixture SEMs with non‐ignorable missing data. The main objective of this paper is to develop a Bayesian approach for analysing mixture SEMs with an unknown number of components and non‐ignorable missing data. A simulation study shows that Bayesian estimates obtained by the proposed Markov chain Monte Carlo methods are accurate and the Bayes factor computed via a path sampling procedure is useful for identifying the correct number of components, selecting an appropriate missingness mechanism, and investigating various effects of latent variables in the mixture SEMs. A real data set on a study of job satisfaction is used to demonstrate the methodology.  相似文献   
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