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71.
A possible explanation for why students do not benefit from learner-controlled instruction is that they are not able to accurately monitor their own performance. The purpose of this study was to investigate whether and how the accuracy of metacognitive judgments made during training moderates the effect of learner control on performance when solving genetics tasks. Eighty-six undergraduate students solved self-selected genetics tasks using either a full learner control or a restricted learner control. Results indicated that learner control effectiveness was moderated by the absolute accuracy (i.e., absolute bias) of metacognitive judgments, and this accuracy was a better predictor of learning performance for full learner control than for restricted learner control. Furthermore, students’ prior knowledge predicted absolute accuracy of both ease-of-learning judgments (EOLs) and retrospective confidence judgments (RCJs) during training, with higher prior knowledge resulting in a better absolute accuracy. Overall, monitoring guided control, that is, EOLs predicted time-on-task and invested mental effort regardless of the degree of learner control, whereas RCJs predicted the total training time, but not the number of tasks selected during training. These results suggest that monitoring accuracy plays an important role in effective regulation of learning from problem-solving tasks, and provide further evidence that metacognitive judgments affect study time allocation in problem solving context.  相似文献   
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Background and objective

Stroke volume variation (SVV) has high sensitivity and specificity in predicting fluid responsiveness. However, sinus rhythm (SR) and controlled mechanical ventilation (CV) are mandatory for their application. Several studies suggest a limited applicability of SVV in intensive care unit (ICU) patients. We hypothesized that the applicability of SVV might be different over time and within certain subgroups of ICU patients. Therefore, we analysed the prevalence of SR and CV in ICU patients during the first 24 h of PiCCO-monitoring (primary endpoint) and during the total ICU stay. We also investigated the applicability of SVV in the subgroups of patients with sepsis, cirrhosis, and acute pancreatitis.

Methods

The prevalence of SR and CV was documented immediately before 1241 thermodilution measurements in 88 patients.Results: In all measurements, SVV was applicable in about 24%. However, the applicability of SVV was time-dependent: the prevalence of both SR and CV was higher during the first 24 h compared to measurements thereafter (36.1% vs. 21.9%; P<0.001). Within different subgroups, the applicability during the first 24 h of monitoring ranged between 0% in acute pancreatitis, 25.5% in liver failure, and 48.9% in patients without pancreatitis, liver failure, pneumonia or sepsis.

Conclusions

The applicability of SVV in a predominantly medical ICU is only about 25%–35%. The prevalence of both mandatory criteria decreases over time during the ICU stay. Furthermore, the applicability is particularly low in patients with acute pancreatitis and liver failure.
  相似文献   
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Different approaches have been used to analyse international collaboration in science but none can fully explain its rapid growth. Using international co-authorships, we test the hypothesis that international collaboration is a self-organising network. Applying tools from network analysis, the paper shows that the growth of international co-authorships can be explained based on the organising principle of preferential attachment, although the attachment mechanism deviates from an ideal power-law. Several explanations for the deviation are explored, including that of the influence of institutional constraints on the mechanism of self-organisation.  相似文献   
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This study examined the reading achievement, metacognitive knowledge related to reading and memory, reading self-concept, and interest in reading of 140 German school students in Grades 3 and 4. The results indicated significant correlations between the metacognitive variables, motivational variables, and amongst metacognitive and motivational variables, as well as with reading achievement variables. The examination of good and poor readers showed significant differences in metacognitive knowledge of reading and memory, reading self-concept, interest in reading, and in teacher judgements of reading achievement between the groups. Differences between Grade 3 and 4 students were found in their word decoding skills, metacognitive knowledge about reading and memory, and teacher judgements of reading achievement. Results of the regression analysis indicated that reading achievement was predicted by grade level, word decoding, and teacher evaluations of reading achievement. The causal modelling indicated that motivation and metacognition affect reading comprehension in different ways. The findings are discussed in terms of future research and their educational implications.  相似文献   
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Mainly for methodological reasons, little is known about the course of development of early cognitive competencies diagnosed with the violation of expectation (VoE) method in infants. The goal of this research was to evaluate the use of pupillometry as a unified approach to assess expectancy violations during and beyond the “dark ages” between 1 and 3 years. We tested children aged 1–6 years and adults (N = 279) with pictures of animals combined with matching or mismatching animal sounds. All age groups exhibited significantly greater pupil dilation in mismatched than matched trials. We conclude that pupillometry is a viable alternative to the VoE method that, by contrast to the latter, can be used throughout the life span.  相似文献   
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