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891.
Mothers with substance use disorders (SUDs) typically have trauma histories and psychosocial difficulties that lead to poor social-emotional functioning and disrupted mother–child relationships. This 12-month study explored associations of family adverse circumstances and services (case management, therapeutic, and community-based) received by 57-mothers with SUDs and their infants (less than 24-months-old) with changes in social-emotional functioning. All mothers were enrolled in a relationship-based case management program (Parent–Child Assistance Program [PCAP]) that emphasized connecting mothers to appropriate community services. A subset of mothers was additionally provided a trauma-focused psychotherapeutic intervention (infant–parent psychotherapy [IPP]). Dyads in both treatment groups improved in overall social-emotional functioning as assessed by the Functional Emotional Assessment Scale (FEAS). A combined-sample regression analysis revealed that improved FEAS scores were significantly predicted by the number of community services received but not by PCAP case management hours (IPP was not included in this analysis). More adverse circumstances were associated with less improvement in social-emotional functioning in the children; but among the mothers trauma level did not predict FEAS scores. We also found a moderating effect of trauma: Dyads with relatively more adversity showed a significantly greater association of community services received with improvement in FEAS scores than did those with relatively less adversity.  相似文献   
892.
N‐of‐1 study designs involve the collection and analysis of repeated measures data from an individual not using an intervention and using an intervention. This study explores the use of semi‐parametric and parametric bootstrap tests in the analysis of N‐of‐1 studies under a single time series framework in the presence of autocorrelation. When the Type I error rates of bootstrap tests are compared to Wald tests, our results show that the bootstrap tests have more desirable properties. We compare the results for normally distributed errors with those for contaminated normally distributed errors and find that, except when there is relatively large autocorrelation, there is little difference between the power of the parametric and semi‐parametric bootstrap tests. We also experiment with two intervention designs: ABAB and AB, and show the ABAB design has more power. The results provide guidelines for designing N‐of‐1 studies, in the sense of how many observations and how many intervention changes are needed to achieve a certain level of power and which test should be performed.  相似文献   
893.
894.
This study investigates whether the visual–auditory (VA) shadowing method can better facilitate vocabulary learning for learners of Japanese as a second language (JSL) than the visual–visual (VV) shadowing method in K-8 immersion education. Learning vocabulary involves three aspects: meaning, orthography, and pronunciation. The Japanese language has complex orthography and pronunciation. Learners of Japanese need to learn three kinds of orthographic characters: ideographs (kanji) and two kinds of syllabic characters (hiragana and katakana). In addition, because the pronunciation of kanji can vary by context, learners must learn several pronunciations for a single kanji character. This study explores a reasonable way to learn pronunciations of kanji and compares VA shadowing (n = 48) and VV shadowing (n = 47) to investigate which condition better facilitates learning the pronunciation of Japanese ideographs. The analysis suggests that compared to the VV shadowing condition (p < .05), the VA shadowing condition is more effective for Level 3 learners but not for Level 2 or Level 1 learners.  相似文献   
895.
896.
897.
Life-satisfaction judgments are ubiquitously used as indicators of wellbeing. The construct validity of these judgments relies heavily on self–informant agreement. However, agreement is necessary, but not sufficient to claim that life-satisfaction judgments are valid. In addition, self–informant agreement should be based on the use of valid information about satisfaction with important life domains. An alternative possibility is that agreement is based on impressions about personality traits. We tested these two hypotheses in a model that predicted self-ratings and informant ratings of life satisfaction from shared perceptions of personality and satisfaction with life domains. In a round-robin study of families, we found that life-domains were the key predictor of self–informant agreement. However, the Depressiveness facet of Neuroticism had a small direct effect. In addition, it was indirectly related to self–informant agreement because it predicts lower satisfaction in important life-domains that were used to form life-satisfaction judgments.  相似文献   
898.
Hick’s law, one of the few law-like relationships involving human performance, expresses choice reaction time as a linear function of the mutual information between the stimulus and response events. However, since this law was first proposed in 1952, its validity has been challenged by the fact that it only holds for the overall reaction time (RT) across all the stimuli, and does not hold for the reaction time (RTi) for each individual stimulus. This paper introduces a new formulation in which RTi is a linear function of (1) the mutual information between the event that stimulus i occurs and the set of all potential response events and (2) the overall mutual information for all stimuli and responses. Then Hick’s law for RT follows as the weighted mean of each side of the RTi equation using the stimulus probabilities as the weights. The new RTi equation incorporates the important speed–accuracy trade-off characteristic. When the performance is error-free, RTi becomes a linear function of two entropies as measures of stimulus uncertainty or unexpectancy. Reanalysis of empirical data from a variety of sources provide support for the new law-like relationship.  相似文献   
899.
Rural youth in China experience numerous challenges during their transition into adulthood. Yet, research on this transition and its relevant influential factors is rare. Through the lens of family systems theory, this study examined the impacts of family dynamics (i.e., interparental and parent–adolescent interactions) in adolescence on the psychological adjustment of youth as they transition into adulthood. Participants were 1330 youth and their mothers in rural Gansu. In 2004, mothers completed questionnaires of interparental and parent–adolescent interactions when youth were adolescents (Mage = 15.03, SD = 1.15). In 2009, youth completed questionnaires of depression and self-esteem when they were emerging adults (Mage = 20.03, SD = 1.15). Results of structural equation modelling suggested that while interparental interactions in adolescence were not associated with the psychological adjustment of youth in emerging adulthood, positive parent–adolescent interactions in adolescence predicted better psychological adjustment of youth in emerging adulthood. Furthermore, mediation analysis showed that although interparental interactions did not directly affect the psychological adjustment of youth, they were positively associated with parent–adolescent interactions, which in turn contributed to the psychological adjustment of youth. The results reveal an enduring influence of family dynamics on psychological adjustment among rural Chinese youth during the transition into adulthood.  相似文献   
900.
Metastable-state alloy powders are usually synthesised by milling and occur as products of mechanical alloying (MA), but they are rarely used as starting materials for other MA processes. In this work, metastable-state alloy powders, including supersaturated solid-solution Cr(Mo)s and amorphous Cr(Mo)a were prepared in advance. Then, the Cr(Mo)s/Cr(Mo)a powder mixture was mechanically alloyed with elemental Cu to form Cu–Mo–Cr alloy. The effects of the metastable-state powder Cr(Mo)s/Cr(Mo)a on MA of the immiscible Cu–Mo–Cr system were evaluated. Phases and microstructures of the milled powders were analysed by XRD and TEM, respectively. The results show that amorphous Cu-60wt.%Cr(Mo) and supersaturated solid-solution Cu-20wt.%Cr(Mo) alloy powders can be synthesised by MA. It is concluded that MA of the Cu–Mo–Cr ternary alloy system is significantly promoted when elemental Cu powder is milled with metastable-state alloy powder Cr(Mo)s/Cr(Mo)a. Furthermore, the promoting effect of amorphous Cr(Mo)a on MA the Cu–Mo–Cr alloy system is much greater than that of supersaturated solid-solution Cr(Mo)s, during the milling process.  相似文献   
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