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921.
We describe a patient with progressive disorder of speech, without language impairment (opercular syndrome). Morphometric analysis confirmed asymmetric volume reduction of the precentral areas (>left). Diffusion imaging showed significant white matter changes in the left frontal lobe, with specific involvement of the left corticobulbar tract and connections between supplementary/pre‐supplementary motor areas and the frontal operculum (frontal aslant tract). We suggest that the organization of expressive language includes a ‘low level’ motor system principally distributed in the left hemisphere that shows specific susceptibility to neurodegeneration, distinct from neural systems subtending praxic, and cognitive aspects of language.  相似文献   
922.
From the academic frontier of modernity and postmodernity,the author aims at exploring the fission between modernity and postmodernity and also the characteristics of postmodern cultural media from a philosophical vantage point.This paper illustrates three aspects of Western modernity:individual modernity,social modernity,and instrumental modernity,and it also clarifies the issues in modernity,starting by explaining three forms of the cultural fission:avant-garde,modernism,and postmodernism.The paper then demonstrates that the rise of postmodernity represents a new transformation and new characteristics of contemporary Westem spirit,namely,the collision and compatibility of various concepts,in which popular culture and high culture,mass culture and elite culture,fashion and games as well as noise and silence have constituted an uncanny landscape of cultural media.This eerie landscape displays the indeterminacy of language,culture,art,consciousness,and aesthetics.From the perspective of theoretical innovation,the author proposes that the postmodem cultural media always displays its commodity and instrumentality,plays and entertainment,anti-culture and anti-art,replication and fabrication logically and practically as an outcome of post-industrial society.In conclusion,three critical issues are addressed:personal spiritual belief,the development of mass culture,and aesthetic principles.The postmodem cultural media has deeply influenced traditional culture,aesthetics,and how they are evaluated,resulting in cultural conflicts and a humanistic dilemma in the world of contemporary capitalism.  相似文献   
923.
924.
925.
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   
926.
Multidimensional computerized adaptive testing (MCAT) has received increasing attention over the past few years in educational measurement. Like all other formats of CAT, item replenishment is an essential part of MCAT for its item bank maintenance and management, which governs retiring overexposed or obsolete items over time and replacing them with new ones. Moreover, calibration precision of the new items will directly affect the estimation accuracy of examinees’ ability vectors. In unidimensional CAT (UCAT) and cognitive diagnostic CAT, online calibration techniques have been developed to effectively calibrate new items. However, there has been very little discussion of online calibration in MCAT in the literature. Thus, this paper proposes new online calibration methods for MCAT based upon some popular methods used in UCAT. Three representative methods, Method A, the ‘one EM cycle’ method and the ‘multiple EM cycles’ method, are generalized to MCAT. Three simulation studies were conducted to compare the three new methods by manipulating three factors (test length, item bank design, and level of correlation between coordinate dimensions). The results showed that all the new methods were able to recover the item parameters accurately, and the adaptive online calibration designs showed some improvements compared to the random design under most conditions.  相似文献   
927.
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   
928.
Examinee‐selected item (ESI) design, in which examinees are required to respond to a fixed number of items in a given set, always yields incomplete data (i.e., when only the selected items are answered, data are missing for the others) that are likely non‐ignorable in likelihood inference. Standard item response theory (IRT) models become infeasible when ESI data are missing not at random (MNAR). To solve this problem, the authors propose a two‐dimensional IRT model that posits one unidimensional IRT model for observed data and another for nominal selection patterns. The two latent variables are assumed to follow a bivariate normal distribution. In this study, the mirt freeware package was adopted to estimate parameters. The authors conduct an experiment to demonstrate that ESI data are often non‐ignorable and to determine how to apply the new model to the data collected. Two follow‐up simulation studies are conducted to assess the parameter recovery of the new model and the consequences for parameter estimation of ignoring MNAR data. The results of the two simulation studies indicate good parameter recovery of the new model and poor parameter recovery when non‐ignorable missing data were mistakenly treated as ignorable.  相似文献   
929.
Research has shown that children and adolescents with attentional control deficits tend to have high anxiety and exhibit threat‐related selective attentional bias. This study aimed to investigate how positive and negative attentional biases would interact with attentional control on dispositional anxiety. One hundred and twenty participants aged 18 years of age or younger participated in a visual dot‐probe task to measure their attentional bias and completed psychological questionnaires to measure their trait anxiety, and attentional control. Mean reaction times to the probe in milliseconds were used to measure attentional bias. Overall, our participants showed a bigger tendency towards attending to positive emotional stimuli than to negative emotional stimuli. Adolescents with high dispositional anxiety showed poorer attentional control. Regression analyses showed that attentional control interact with negative attentional bias to affect anxiety. For participants with high attentional control, higher negative attentional bias was associated with lower trait anxiety. Trait anxiety was not related to negative attentional bias for participants with low attentional control. Positive attentional bias showed no significant relationship with dispositional anxiety, either alone or in interaction with attentional control. Theoretical and clinical implications of the findings are also discussed.  相似文献   
930.
Sivin Kit 《Dialog》2017,56(3):260-271
How can Luther's contribution in theology and lessons arising from the Reformation have any relevance for Christians in Muslim‐majority Malaysia? In this article, I propose that a reflection on Luther's understanding of the so‐called “doctrine of two kingdoms”—better understood as God's two‐fold governance—offers a critical contribution that not only is relevant for the Malaysian Christian community, but also may have intercultural and interreligious implications for dialogue and engagement with the Muslim majority for interreligious solidarity and the common good.  相似文献   
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