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281.
Abstract

This paper evaluated multilevel reliability measures in two-level nested designs (e.g., students nested within teachers) within an item response theory framework. A simulation study was implemented to investigate the behavior of the multilevel reliability measures and the uncertainty associated with the measures in various multilevel designs regarding the number of clusters, cluster sizes, and intraclass correlations (ICCs), and in different test lengths, for two parameterizations of multilevel item response models with separate item discriminations or the same item discrimination over levels. Marginal maximum likelihood estimation (MMLE)-multiple imputation and Bayesian analysis were employed to evaluate the accuracy of the multilevel reliability measures and the empirical coverage rates of Monte Carlo (MC) confidence or credible intervals. Considering the accuracy of the multilevel reliability measures and the empirical coverage rate of the intervals, the results lead us to generally recommend MMLE-multiple imputation. In the model with separate item discriminations over levels, marginally acceptable accuracy of the multilevel reliability measures and empirical coverage rate of the MC confidence intervals were found in a limited condition, 200 clusters, 30 cluster size, .2 ICC, and 40 items, in MMLE-multiple imputation. In the model with the same item discrimination over levels, the accuracy of the multilevel reliability measures and the empirical coverage rate of the MC confidence intervals were acceptable in all multilevel designs we considered with 40 items under MMLE-multiple imputation. We discuss these findings and provide guidelines for reporting multilevel reliability measures.  相似文献   
282.
The adult human brain quickly adapts to regular temporal sequences, and emits a sequence of novelty responses when these regularities are violated. These novelty responses have been interpreted as error signals that reflect the difference between the incoming signal and predictions generated at multiple cortical levels. Do infants already possess such a hierarchy of violation-detection mechanisms? Using high-density recordings of event-related potentials during an auditory local–global violation paradigm, we show that three-month-old infants process novelty in temporal sequences at two distinct levels. Violations of local expectancies, such as perceiving a deviant vowel “a” after repeated presentation of another vowel i-i-i, elicited an early auditory mismatch response. Conversely, violations of global expectancies, such as hearing the rare sequence a-a-a-a instead of the frequent sequence a-a-a-i, modulated this early mismatch response and led to a late frontal negative slow wave, whose cortical sources included the left inferior frontal region. These results suggest that the infant brain already possesses two dissociable systems for temporal sequence learning.  相似文献   
283.
脓毒症多呈现典型的促炎效应和抗炎反应,并与获得性免疫功能障碍同时出现,且免疫细胞中超过80%的基因表达发生改变。由于单核/巨噬细胞细胞因子谱的改变、主要组织相容性复合体Ⅱ类抗原(MHCⅡ)及共刺激分子表达下降以及树突状细胞的凋亡,诱发细胞免疫功能下降;中性粒细胞活性降低和补体系统的激活,又增加感染易感性。T淋巴细胞表现...  相似文献   
284.
Strong associations between target stimuli and responses usually facilitate fast and effortless reactions. The present study investigated whether long-term associations between distractor stimuli and responses modulate behavior. In particular, distractor stimuli can affect behavior due to distractor-based stimulus-response retrieval, a phenomenon called distractor-response binding: An ignored stimulus becomes temporarily associated with a response and retrieves it at stimulus repetition. In a flanker task, participants ignored left and right pointing arrows and responded to a target letter either with left and right (strongly associated) responses or with upper and lower (weakly associated) responses. Binding effects were modulated in dependence of the long-term association strength between distractors and responses. If the association was strong (arrows pointing left and right with left and right responses), binding effects emerged but only in case of compatible responses. If the long-term association between distractors and responses was weak (arrows pointing left and right with upper and lower responses), binding was weaker and not modulated by compatibility. In contrast, sequential compatibility effects were not modulated by association strength between distractor and response. The results indicate that existing long-term associations between stimuli responses may modulate the impact of an ignored stimulus on action control.  相似文献   
285.
We present a single-subject prospective outcome study of a man with severe morphing fear and long history of OCD who was not helped by previous interventions, and who received an adapted form of cognitive behavior therapy (CBT) as part of this study. Treatment consisted of a cognitively focused approach tailored to address his fear of morphing and included developing a stronger sense of self-stability. We describe the details of the case, the treatment protocol, and the therapeutic outcomes as assessed over 36 weeks by questionnaires, rating scales, and semistructured interviews. The intervention was effective in eradicating the patient’s morphing fears and reducing other symptoms of OCD, anxiety, and depression. The presented case illustrates the need to appropriately conceptualize, assess, and address the specific nature of morphing fear symptoms in treatment.  相似文献   
286.
Background and objectives: Developmental theorists posit that temperament contributes to preadolescent’s stress response styles. Findings from empirical studies, however, have yielded mixed results, thus indicating a need to consider moderators of this relation. Utilizing an analytic framework guided by resiliency theory [Zimmerman, M. A. (2013). Resiliency theory: A strengths-based approach to research and practice for adolescent health. Health Education &; Behavior, 40, 381–383], this study examined achievement goal orientation as a moderator of the relation between temperament and stress response styles.

Methods: 96 preadolescent–parent dyads (Mage?=?10.30 years, range?=?9–12 years) participated in the study. Preadolescents reported on their achievement goal orientation, coping and involuntary stress responses (ISRs) styles and a parent reported on children’s temperament.

Results: Multiple regressions revealed that effortful control positively predicted preadolescent’s predominant use of engagement coping and negatively predicted predominance of ISRs, but only for children with a predominant mastery goal orientation. For preadolescents with a predominant performance goal orientation, effortful control negatively predicted the predominant use of engagement coping and positively predicted predominance of ISRs. Negative affectivity and its interaction with goal orientation did not predict coping or ISR styles.

Conclusions: Findings suggest that a predominant mastery goal orientation may function as a promotive factor by enhancing the contribution of effortful control to engagement coping styles and buffering against unmanaged reactivity.  相似文献   
287.
Cognitive-behavioral therapy (CBT), consisting of exposure and response prevention (EX/RP), is both efficacious and preferred by patients with obsessive–compulsive disorder (OCD), yet few receive this treatment in practice. This study describes the implementation of an Internet-based CBT program (ICBT) developed in Sweden in individuals seeking OCD treatment in New York. After translating and adapting the Swedish ICBT for OCD, we conducted an open trial with 40 adults with OCD. Using the RE-AIM implementation science framework, we assessed the acceptability, feasibility, and effectiveness of ICBT. The Yale–Brown Obsessive Compulsive Scale (Y-BOCS) was the primary outcome measure. Of 40 enrolled, 28 participants completed the 10-week ICBT. In the intent-to-treat sample (N = 40), Y-BOCS scores decreased significantly over time (F = 28.12, df = 2, 49, p < . 001). Depressive severity (F = 5.87, df = 2, 48, p < . 001), and quality of life (F = 12.34, df = 2, 48, p < . 001) also improved. Sensitivity analyses among treatment completers (N = 28) confirmed the intent-to-treat results, with a large effect size for Y-BOCS change (Cohen’s d = 1.38). ICBT took less time to implement than face-to face EX/RP and participants were very to mostly satisfied with ICBT. On a par with results in Sweden, the adapted ICBT program reduced OCD and depressive symptoms and improved quality of life among individuals with moderate to severe OCD. Given its acceptability and feasibility, ICBT deserves further study as a way to increase access to CBT for OCD in the United States.  相似文献   
288.
We report here for the first time the development of ‘age-hardened/toughened’ ceramic alloy based on MgO in the bulk polycrystalline form. This route allows for the facile development of a ‘near-ideal’ microstructure characterized by the presence of nanosized and uniformly dispersed second-phase particles (MgFe2O4) within the matrix grains, as well as along the matrix grain boundaries, in a controlled manner. Furthermore, the intragranular second-phase particles are rendered coherent with the matrix (MgO). Development of such microstructural features for two-phase bulk polycrystalline ceramics is extremely challenging following the powder metallurgical route usually adopted for the development of bulk ceramic nanocomposites. Furthermore, unlike for the case of ceramic nanocomposites, the route adopted here does not necessitate the usage of nano-powder, pressure/electric field-assisted sintering techniques and inert/reducing atmosphere. The as-developed bulk polycrystalline MgO–MgFe2O4 alloys possess considerably improved hardness (by ~52%) and indentation toughness (by ~35%), as compared to phase pure MgO.  相似文献   
289.
Given the relationship between internalizing disorders and deficits in emotion regulation in youth, the emotion science literature has suggested several avenues for increasing the efficacy of interventions for youth presenting with anxiety and depression. These possibilities include the identification and addition of emotion-regulation skills to existing treatment packages and broadening the scope of those emotions addressed in cognitive-behavioral treatments. Current emotion-focused interventions designed to meet one or both of these goals are discussed, and the developmental influences relevant to the selection of emotion-focused treatment goals are explored using the framework of a modal model of emotion regulation. These various lines of evidence are woven together to support the utility of a novel emotion-focused, cognitive-behavioral intervention, the Unified Protocol for the Treatment of Emotional Disorders in Youth, a transdiagnostic treatment protocol that aims to treat the range of emotional disorders (i.e., anxiety and depression) simultaneously. Avenues for future directions in treatment outcome and assessment of emotion regulation are also discussed.  相似文献   
290.
Undergraduate counselors‐in‐training completed the Substance Abuse Attitude Survey, which measures treatment intervention, treatment optimism, and nonstereotypical attitudes. Treatment optimism was positively correlated with nonstereotypical attitudes and treatment intervention. Results indicated that treatment intervention and nonstereotypical attitudes must be addressed in addiction counseling courses.  相似文献   
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