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Daniel Ansari Roland H. Grabner Karl Koschutnig Gernot Reishofer Franz Ebner 《Learning and individual differences》2011,21(6):636-643
Data from both neuropsychological and neuroimaging studies have implicated the left inferior parietal cortex in calculation. Comparatively less attention has been paid to the neural responses associated with the commission of calculation errors and how the processing of arithmetic errors is modulated by individual differences in mathematical competence. Do more competent individuals exhibit a different brain response to errors than less mathematically able individuals? These outstanding questions were addressed in the present functional Magnetic Resonance Imaging (fMRI) study through an investigation of which brain regions respond more to erroneously versus correctly solved arithmetic problems while a group of 24 adult participants with varying levels of mathematical competence solved problems of all four arithmetic operations. Despite high levels of accuracy, a robust main effect of accuracy (incorrect vs. correct) was observed in both medial and lateral regions of the prefrontal cortex. These regions have frequently been associated with both the detection of errors and the deployment of cognitive control following an error. Furthermore, mathematical competence was found to modulate the activation of an area in the right dorsolateral prefrontal cortex. Specifically, individuals with relatively higher mathematical competence (n = 12) were found to activate this region more for incorrectly solved trials than their less mathematically competent peers (n = 12). Taken together, these findings suggest that the commission of arithmetic errors modulates responses of prefrontal regions and, moreover, that activation of the right lateral prefrontal cortex during arithmetic errors is affected by individual differences in mathematical competence. In view of the evidence associating the lateral prefrontal cortex with the implementation of cognitive control, we suggest that individuals with relatively high mathematical competence may exhibit greater awareness of calculation mistakes and implement greater control following the commission of errors. 相似文献
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Melissa M. Patchan Christian D. Schunn Wilfried Sieg Dawn McLaughlin 《Technology, Pedagogy and Education》2016,25(3):269-286
While online instructional technologies are becoming more popular in higher education, educators’ opinions about online learning tend to be generally negative. Furthermore, many studies have failed to systematically examine the features that distinguish one instructional mode from another, which weakens possible explanations for why online instructional technology can be beneficial. The current study isolates three benefits of the authors’ particular online instructional technology: (1) providing flexibility in how students learn, (2) offering immediate and targeted feedback and (3) increasing student participation and engagement with instructional material. Maximum benefits were observed when students used the online instructional technology to prepare for their face-to-face class – that is, students with this blended instruction learned twice as much content in the same amount of time in comparison to students with face-to-face instruction alone, without creating an atypically high workload. 相似文献
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Gernot Zollner Peter Fickert und Michael Trauner 《Wiener klinische Wochenschrift Education》2007,2(3):125-140
Ohne Zusammenfassung 相似文献
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Abstract We used high-resolution Raman spectroscopy and differential scanning calorimetry for a comprehensive analysis of carbon black-filled polyethylene ski base grades at processing stages from the raw material to the structured ski base. Based on Raman mapping, we assessed the applicability of an advanced evaluation procedure for amorphous, disordered, and crystalline phase fractions of polyethylene for polyethylene extrusion and sinter grades. For sinter grades, a sufficient segregation between carbon black and polyethylene was confirmed, allowing for a comprehensive Raman spectroscopic morphological analysis. Significant morphological changes in polyethylene due to processing from the raw material to the semi-finished film and to the structured ski base were identified. Throughout the processing chain, we observed a decrease in crystallinity and an increase in the amorphous phase fraction. Although the raw material and the sintered semi-finished film exhibited a different but uniform polyethylene morphology, the morphological changes due to structuring of the ski base are limited to the top surface layer. The highest amorphous phase fractions were detected in the surface of the structured ski bases. 相似文献
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Rational individuals may use a tax or license-fee financed public service TV channel to mitigate the paradox of rational ignorance. The approach presented in this article assumes that increased consumption of information by voters improves democratic decisions, but marginal returns decrease. Depending on how fast marginal returns decrease, the public service TV channel broadcasts either only (unbiased serious) news or, to induce voters to watch the informational content, sports and shows (entertainment) as well. 相似文献
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Abstract Does the presentation and use of the search space matter for complex problem solving tasks? We address these questions for the construction of proofs in sentential logic. Using a fully computerized logic course, we isolated crucial features of computer environments and assessed their relative pedagogical effectiveness. After being given a pretest for logical aptitude, students were divided into three matched groups, each of which used a distinct computerized environment to construct proofs. All students were presented with identical course material on sentential logic for approximately five weeks. Students completed more than one hundred exercises during those five weeks and took a midterm at the end of the period. The group using the most informative and most flexible interface performed substantially better on the midterm— the difference was particularly striking for hard problems. In two follow‐up experiments we added strategic problem solving help; student performance improved again (entirely on the difficult problems). Our interpretation is, first, flexibility in traversing the search space leads students to see the global structure of the search space and to develop effective heuristics; second, strategic help reinforces and extends these heuristics. 相似文献
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Dietmar Enko Gernot Kriegsh?user Robert Stolba Elfriede Worf Gabriele Halwachs-Baumann 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(2):203-212
Introduction
Recently several diagnostic manufacturers have launched new 25-hydroxy-vitamin D (25[OH]D) assays, which are aligned to the National Institute of Standards and Technology (NIST) Standard Reference Materials (SRM) (NIST, Gaithersburg, Maryland). The aim of this study was to compare the performance of one liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, one enzyme linked immunosorbent assay (ELISA), and one recalibrated and previous version of a chemiluminescence immunoassay (CLIA).Material and methods
Serum-aliquots of 198 patient samples from routine 25(OH)D analysis were measured by the ClinMass® LC-MS/MS Complete Kit (RECIPE Chemicals + Instruments GmbH, Munich, Germany), the ORGENTEC 25(OH)D3/D2 ELISA (ORGENTEC Diagnostika GmbH, Mainz, Germany), the recalibrated Immunodiagnostic Systems (IDS)-iSYS 25(OH)DS and the previous used IDS-iSYS 25(OH)D CLIA (Immunodiagnostic Systems Ltd, Boldon, United Kingdom). Bland-Altman and Deming regression analyses were calculated for methods comparison of all tested 25(OH)D assays. The LC-MS/MS method was defined as the reference method. Within-run and between-run precision measurements were performed for all methods with three different concentration levels.Results
Compared to the LC-MS/MS method, the new IDS-iSYS 25(OH)DS and ORGENTEC 25(OH)D3/D2 assay demonstrated mean relative biases of 16.3% and 17.8%. The IDS-iSYS 25(OH)D assay showed the lowest mean bias of 1.5%. Deming regression analyses of the recalibrated IDS-iSYS 25(OH)DS and the ORGENTEC 25(OH)D3/D2 assay showed proportional differences, when compared to the reference method. All assays showed a within-run and between-run imprecision of ≤ 20% at each of the evaluated concentration levels.Conclusions
The evaluated standardized immunoassays and LC-MS/MS are useful methods for measuring 25(OH)D serum-levels in clinical laboratories.Key words: vitamin D, immunoassays, liquid chromatography-tandem mass spectrometry, reference standards, quality improvement 相似文献
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