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The authors report results of a study into the role of components of first-language (L1; Dutch) and second-language (L2; English) reading comprehension. Differences in the contributions of components of L1 and L2 reading comprehension are analyzed, in particular processing speed in L1 and L2. Findings indicate that regression weights of the L1 and L2 components are different. Although correlations between most processing speed components and reading comprehension are substantial, there are no unique contributions to the explanation of either L1 or L2 reading comprehension when linguistic and metacognitive knowledge are accounted for. In addition, L1 reading comprehension is shown to have a large contribution to L2 reading comprehension, supporting theories of L1-L2 transfer of reading skills. Results are discussed from a developmental perspective. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study investigated the relationship between reading comprehension development of 389 adolescents in their dominant language (Language 1 [L1], Dutch) and a foreign language (Language 2 [L2], English). In each consecutive year from Grades 8 through 10, a number of measurements were taken. Students' reading comprehension, their linguistic knowledge (vocabulary and grammar knowledge) and processing efficiency (speed of word recognition and sentence comprehension) in both languages, and their metacognitive knowledge about reading were assessed. The relative strengths of the effects of these components of reading were analyzed to distinguish among 3 hypotheses about the relationship between L1 and L2 reading comprehension: the transfer hypothesis, the threshold hypothesis, and the processing efficiency hypothesis. The transfer hypothesis predicts a strong relationship between L1 and L2 reading comprehension and a strong effect of metacognitive knowledge on L2 reading comprehension, whereas the threshold and processing efficiency hypotheses predict a more important role of language-specific knowledge and processing skills. Results support the transfer hypothesis, although language-specific knowledge and fluency also contribute to L2 reading performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Embar  Varun  Srinivasan  Sriram  Getoor  Lise 《Machine Learning》2021,110(7):1847-1866

Statistical relational learning (SRL) and graph neural networks (GNNs) are two powerful approaches for learning and inference over graphs. Typically, they are evaluated in terms of simple metrics such as accuracy over individual node labels. Complex aggregate graph queries (AGQ) involving multiple nodes, edges, and labels are common in the graph mining community and are used to estimate important network properties such as social cohesion and influence. While graph mining algorithms support AGQs, they typically do not take into account uncertainty, or when they do, make simplifying assumptions and do not build full probabilistic models. In this paper, we examine the performance of SRL and GNNs on AGQs over graphs with partially observed node labels. We show that, not surprisingly, inferring the unobserved node labels as a first step and then evaluating the queries on the fully observed graph can lead to sub-optimal estimates, and that a better approach is to compute these queries as an expectation under the joint distribution. We propose a sampling framework to tractably compute the expected values of AGQs. Motivated by the analysis of subgroup cohesion in social networks, we propose a suite of AGQs that estimate the community structure in graphs. In our empirical evaluation, we show that by estimating these queries as an expectation, SRL-based approaches yield up to a 50-fold reduction in average error when compared to existing GNN-based approaches.

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The sintering properties of La1−xSrxFeO3−δ (x = 0.1, 0.25) mixed conductors have been investigated with particular emphasis on the effect of secondary phases due to cation non-stoichiometry (±5 mol% La excess and deficiency). Secondary phases, located at grain boundaries in cation non-stoichiometric materials, increased the sintering temperature compared to single-phase materials. Extensive swelling in final stage of sintering was observed in all materials, which resulted in micro-porous materials. The swelling was most pronounced in the phase pure and two-phase materials due to La-deficiency, while refractory secondary phases in La-excess materials inhibited both sintering, grain growth and swelling. In La-deficient materials, formation of molten secondary phases resulted in rapid swelling due to viscous flow. The present findings demonstrated the importance of controlling sintering temperature and time, as well as careful control of the cation stoichiometry of La1−xSrxFeO3−δ in order to achieve fully dense and homogenous La1−xSrxFeO3−δ ceramics.  相似文献   
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BACKGROUND: The high incidence of locoregional recurrences and distant metastases after curative surgery for gastric cancer calls for improved locoregional control and systemic adjuvant treatment. METHODS: In a randomized clinical trial on adjuvant FAM2 chemotherapy, quality of surgery was evaluated by comparing surgical and pathology data. Univariate and multivariate analysis was made to evaluate the effect of prognostic factors on survival and time of recurrence in relation to patients, tumor, and therapy. RESULTS: Of 314 patients randomized from 28 European institutions, 159 comprised the control and 155 the FAM2 group. After a median follow-up of 80 months, no statistically significant difference was found between survivals. However, for recurrence time, treated patients had a significant advantage over controls (p = 0.02). At univariate analysis, statistically significant differences in survival and time to progression emerged for T, N, disease stage and "adequacy" of surgery. The multivariate analysis retained preoperative Hb level, T, N, and "adequacy" of surgery for time of survival; and T, N, "adequacy" of surgery and adjuvant chemotherapy for recurrence time. CONCLUSIONS: Disease stage is the most important prognostic factor. "Adequate" surgery has an important effect. Adjuvant FAM2 delayed time of recurrence, but did not influence overall survival.  相似文献   
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Discriminatory and robust typing methods are needed to improve the understanding of the dynamics of food-borne Campylobacter infections and epidemiology in primary animal production. To evaluate the strain discriminatory potential of typing methods, flaA short variable region (SVR) sequencing and Fourier transform infrared (FTIR) spectroscopy were applied on a collection of 102 epidemiologically related and unrelated Campylobacter jejuni strains. Previous application of FTIR spectroscopy for subtyping of Campylobacter has been limited. A subset of isolates, initially discriminated by flaA SVR sequencing, were further subjected to multilocus sequence typing (MLST). It was found that flaA SVR sequencing had a slightly higher discriminatory power than FTIR spectroscopy, based on the Simpson diversity index. The clustering of strains indicated that FTIR spectroscopy is indeed a suitable method for discrimination of Campylobacter. The isolates were assigned to six clusters based on flaA SVR sequences and nine clusters based on the FTIR spectroscopy profiles. Furthermore, the cluster analysis of flaA SVR sequences, MLST, and FTIR spectroscopy profiles showed a high degree of congruence, assigning the isolates to similar cluster structures. In conclusion, FTIR spectroscopy can be applied for subtyping of Campylobacter, and the high discriminatory potential of both flaA SVR sequencing and FTIR spectroscopy render them suitable screening methods for large numbers of strains.  相似文献   
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