Fitting direct covariance structures by the MSTRUCT modeling language of the CALIS procedure

This paper demonstrates the usefulness and flexibility of the general structural equation modelling (SEM) approach to fitting direct covariance patterns or structures (as opposed to fitting implied covariance structures from functional relationships among variables). In particular, the MSTRUCT modelling language (or syntax) of the CALIS procedure (SAS/STAT version 9.22 or later: SAS Institute, 2010) is used to illustrate the SEM approach. The MSTRUCT modelling language supports a direct covariance pattern specification of each covariance element. It also supports the input of additional independent and dependent parameters. Model tests, fit statistics, estimates, and their standard errors are then produced under the general SEM framework. By using numerical and computational examples, the following tests of basic covariance patterns are illustrated: sphericity, compound symmetry, and multiple‐group covariance patterns. Specification and testing of two complex correlation structures, the circumplex pattern and the composite direct product models with or without composite errors and scales, are also illustrated by the MSTRUCT syntax. It is concluded that the SEM approach offers a general and flexible modelling of direct covariance and correlation patterns. In conjunction with the use of SAS macros, the MSTRUCT syntax provides an easy‐to‐use interface for specifying and fitting complex covariance and correlation structures, even when the number of variables or parameters becomes large.     

Neural bases of binocular rivalry

During binocular rivalry, conflicting monocular images compete for access to consciousness in a stochastic, dynamical fashion. Recent human neuroimaging and psychophysical studies suggest that rivalry entails competitive interactions at multiple neural sites, including sites that retain eye-selective information. Rivalry greatly suppresses activity in the ventral pathway and attenuates visual adaptation to form and motion; nonetheless, some information about the suppressed stimulus reaches higher brain areas. Although rivalry depends on low-level inhibitory interactions, high-level excitatory influences promoting perceptual grouping and selective attention can extend the local dominance of a stimulus over space and time. Inhibitory and excitatory circuits considered within a hybrid model might account for the paradoxical properties of binocular rivalry and provide insights into the neural bases of visual awareness itself.     

华西圣教书会的文字事工及其影响(1899-1919)

华西圣教书会于1899年初成立于重庆,存续40余年,于1941年关闭,是基督教在华西地区最重要的文字机构之一①.本文以清末民初为时限,考察华西圣教书会成立过程及其出版、发行状况,并分析基督教文字事业对华西社会变迁所起到的重大作用.     

Development and validation of a Coping with Discrimination Scale: factor structure, reliability, and validity

Four studies were conducted to develop and validate the Coping With Discrimination Scale (CDS). In Study 1, an exploratory factor analysis (N = 328) identified 5 factors: Education/Advocacy, Internalization, Drug and Alcohol Use, Resistance, and Detachment, with internal consistency reliability estimates ranging from .72 to .90. In Study 2, a confirmatory factor analysis (N = 328) provided cross-validation of the 5-factor model as well as evidence for validity of the scale. The validity evidence was similar across racial groups and for males and females. In Study 3, the estimated 2-week test-retest reliabilities (N = 53) were between .48 and .85 for the 5 factors. Education/Advocacy, Internalization, Drug and Alcohol Use, and Detachment were positively associated with active coping, self-blame, substance use, and behavioral disengagement, respectively, providing further support for validity of the CDS. Finally, incremental validity evidence was obtained in Study 4 (N = 220), where it was shown that the CDS explained variance in outcome variables (i.e., depression, life satisfaction, self-esteem, and ethnic identity) that could not be explained by general coping strategies.     

Determinants of Standard Errors of MLEs in Confirmatory Factor Analysis

This paper studies changes of standard errors (SE) of the normal-distribution-based maximum likelihood estimates (MLE) for confirmatory factor models as model parameters vary. Using logical analysis, simplified formulas and numerical verification, monotonic relationships between SEs and factor loadings as well as unique variances are found. Conditions under which monotonic relationships do not exist are also identified. Such functional relationships allow researchers to better understand the problem when significant factor loading estimates are expected but not obtained, and vice versa. What will affect the likelihood for Heywood cases (negative unique variance estimates) is also explicit through these relationships. Empirical findings in the literature are discussed using the obtained results.     

利用脑成像多体素模式分析解码认知的神经表征:原理和应用

多体素模式分析(multi-voxel pattern analysis,MVPA)是一种基于机器学习理论发展出来的新的功能磁共振数据分析技术。MVPA技术通过训练分类器,对由不同认知状态引起的多体素信号模式进行分类。与传统的基于单个体素的分析方法相比,该技术可更敏感地检测脑对认知状态的表征,并使得从神经信号解码认知状态成为可能。文章介绍MVPA技术的基本原理、分析步骤以及可以用MVPA来解决的科学问题,并对应用中可能面临的问题提供了参考建议。     

Application of the stagnant stage concept for monitoring Mn partitioning at the austenite-ferrite interface in the intercritical region for Fe–Mn–C alloys

The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning.     

Detrimental effect of cellular precipitation on the creep strength of Inconel740H

Cellular precipitation (also known as discontinuous precipitation) has been observed at the grain boundaries of a newly developed nickel-based Inconel740H alloy designed for use at 700?°C in advanced ultrasupercritical coal-fired power plants. By means of element mapping and selected area diffraction, the cellular precipitates were identified as Cr-rich M₂₃C₆ carbides. The onset of cellular precipitation was found to follow a pucker mechanism in Inconel740H. The cellular precipitates at the grain boundaries, even at low volume fractions, were severely detrimental to the creep strength at 750?°C. The creep rupture life of Inconel740H containing cellular precipitates at grain boundaries was only one-tenth of that for the alloy without cellular precipitates. The reason for the drastically decreased creep rupture life is attributed to the poor resistance of cellular precipitates to crack propagation during creep.     

关注肿瘤患者避免过度诊疗——解析ASCO大会关于肿瘤诊疗的5项建议

现代肿瘤的诊疗水平已经有了长足的进步,先进的诊断技术使得很多肿瘤得以早期发现并积极治疗,很多晚期患者也不再面临无药可用的境地,但由于临床医生的认识存在偏差,存在过度诊断和过度治疗的问题,进而给患者带来不必要的负担和痛苦。美国临床肿瘤学会（ASC0）年会上发布了一篇名为“ASCO为改善肿瘤治疗质量及医疗花费的5项建议”的文章,特别提出要重视五项临床广泛应用、花费较大,但缺乏高级临床证据的肿瘤治疗或干预措施,也提示我们需要充分评估,综合思考,为合适的患者提供正确的诊治方案,才能给患者带来更大的获益。     

The Role of Sketching States in the Stimulation of Idea Generation: An Eye Movement Study

Sketching is widely used in design to generate creative ideas. Design studies present stimuli during sketching to enhance creativity. This study examines the effect of stimuli presented during different sketching states, especially of those presented during the stuck period. It conducted a sketching experiment that enrolled 41 students with an average of 5.7 years’ practice in industrial design. The sketching with stimuli presented at regular intervals, those with stimuli presented during the stuck period, and those without stimulus were compared. Eye movements during the sketching processes were recorded. The attention to stimuli, and the direct applications of stimuli to design ideas, and the idea connection and idea differentiation were analyzed. Participants sketching with stimuli presented during the stuck period had a higher sketching quality, compared with those in other experimental conditions. They fixated longer on stimuli, built more links among related ideas, and had a more differentiated and balanced exploration. This study then proposed the mechanisms of stimuli processing. The stimuli presented at regular intervals were stored and acted as additional memory. The stimuli presented during the stuck period were dissected and acted as supporter, inducing a more creative sketching.