The specific involvement of verbal and visuospatial working memory in hypermedia learning     

Francesca Pazzaglia  Cristina Toso  Stefano Cacciamani 《British journal of educational technology : journal of the Council for Educational Technology》2008,39(1):110-124

Many models have hypothesized that multimedia comprehension requires the concurrent processing of verbal and visuospatial information by limited information processing systems. However, in spite of the emphasis devoted to the concurrent processing of verbal and visuospatial information, little research has so far investigated the specific role played by verbal and visuospatial abilities in multimedia comprehension. The present paper aims to study the specific involvement of verbal and visuospatial working memory in multimedia learning. Ninety‐two students (39 boys and 53 girls) from a middle school in a small city in the northeast of Italy, were asked to learn new information on the physical and social geography of Germany from a hypermedium. Participants were also required to perform a reading comprehension test, two short‐term memory tasks, and two working memory tasks, which assessed either verbal or visuospatial memory. The results support the hypothesis that both verbal and visuospatial working memory sub‐components play a role in hypermedium processing, but with specific and distinct functions: the performance in the verbal working memory task was able to predict the semantic knowledge children can derive from hypermedia learning. In contrast, visuospatial working memory seemed to have lower connections to the semantic knowledge children derived from a hypermedia document, whereas its role emerged in the ability to construct a representation of the document structure.  相似文献   

NO在赤铁矿(0001)表面吸附的第一性原理计算（英文）     

吴翠霞  孙涛  FABRIS Stefano  杜林 《中国科学院大学学报》2022,39(2):193-200

氮氧化物NO_x（NO,NO₂）是对人类健康有严重危害的大气污染物。近年来研究表明赤铁矿（α-Fe₂O₃）可作为高效光催化剂去除大气中NO_x,但NO_x气体在赤铁矿表面的吸附特性还未明确,阻碍了对其催化机理的进一步认识。基于密度泛函理论,采用包括电子强关联效应的PBE+U以及色散力修正的方法,对NO气体分子在α-Fe₂O₃ （0001）晶面的吸附行为进行深入研究,发现基于PBE+U方法获得的吸附能（E_ad=-0.64eV）比PBE获得的E_ad（-1.31eV）低近50%。这是由于电子强关联项U的引入降低了表面铁原子d轨道对价带顶的贡献,抑制了其化学活性,而NO具有一个未成对的π^*轨道电子,使得其对吸附基体的电子结构格外敏感。与+U不同,色散力修正不会显著改变体系的电子结构,只是使E_ad略有增加（-0.18 eV）。采用统计力学的Langmuir公式计算NO在α-Fe₂O₃ （0001）表面的热力学平衡占据数,发现基于+U的吸附能得到的平衡占据数与实验观测更为一致。这些结果揭示了电子强关联效应在α-Fe₂O₃表面化学中的重要作用,并为进一步研究NO_x在α-Fe₂O₃表面的光催化反应机理奠定了基础。  相似文献   

Aesthetics     

Stefano Predelli 《Philosophical Books》2004,45(3):274-277

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Feedback effects of teaching quality assessment: macro and micro evidence     

Stefano Bianchini 《Assessment & Evaluation in Higher Education》2014,39(3):380-394

This study investigates the feedback effects of teaching quality assessment. Previous literature looked separately at the evolution of individual and aggregate scores to understand whether instructors and university performance depends on its past evaluation. I propose a new quantitative-based methodology, combining statistical distributions and transition probabilities matrices, to take into account the dynamics of teaching quality over time both at the macro and the micro level. Using a three-year longitudinal panel from an Italian university, it is shown that evaluation exercises do not impact future teaching performance at either the university level or the individual level.  相似文献   

The effect of personal orientations toward intergroup relations on moral reasoning     

Stefano Passini 《Journal of moral education》2014,43(1):89-103

This article examined how the group membership of the person being judged influenced the level of moral reasoning. Nearly 200 ordinary Italians were given two measures of moral ingroup inclusiveness (the Bogardus social distance scale and a self-categorization measure) and the short form of Rest’s Defining Issues Test (DIT). The protagonists in the dilemmas were either Italian (ingroup member) or Romanian (outgroup member). Overall, the post-conventional score (P score) was related to higher inclusiveness. However, respondents with a narrow moral ingroup scored lower on post-conventional reasoning when the protagonists were Romanian (outgroup members) than when they were Italian. By contrast, those respondents with an inclusive moral ingroup obtained identical P scores on both types of dilemmas. Inclusiveness of the moral ingroup also mediated the relation of political affiliation and post-conventional reasoning.  相似文献   

Motion analysis of front crawl swimming applying CAST technique by means of automatic tracking     

Stefano Ceccon  Elena Ceseracciu  Zimi Sawacha  Giorgio Gatta  Matteo Cortesi  Claudio Cobelli 《Journal of sports sciences》2013,31(3):276-287

Abstract

Kinematic analysis of swimming is of interest to improve swimming performances. Although the video recordings of underwater swimmers are commonly used, the available methodologies are rarely precise enough to adequately estimate the three dimensional (3D) joint kinematics. This is mainly due to difficulties in obtaining the required kinematic parameters (anatomical landmarks, joint centres and reference frames) in the swimming environment. In this paper we propose a procedure to investigate the right upper limb’s 3D kinematics during front crawl swimming in terms of all elbow and shoulder degrees of freedom (three rotations of the shoulder, two of the elbow). The method is based upon the Calibrated Anatomical Systems Technique (CAST), a technique widely used in clinics, which allows estimation of anatomical landmarks of interest even when they are not directly visible. An automatic tracking technique was adopted. The intra-operator repeatability of the manual tracking was also assessed. The root mean squared difference of three anatomical landmarks, processed five times, is always lower than 8 mm. The mean of the root mean squared difference between trajectories obtained with the different methodologies was found to be lower than 20 mm. Results showed that complete 3D kinematics of at least twice as many frames than without CAST can be reconstructed faster and more precisely.  相似文献   

An evaluation of an adaptive learning system based on multimodal affect recognition for learners with intellectual disabilities     

Penelope J. Standen  David J. Brown  Mohammad Taheri  Maria J. Galvez Trigo  Helen Boulton  Andrew Burton  Madeline J. Hallewell  James G. Lathe  Nicholas Shopland  Maria A. Blanco Gonzalez  Gosia M. Kwiatkowska  Elena Milli  Stefano Cobello  Annaleda Mazzucato  Marco Traversi  Enrique Hortal 《British journal of educational technology : journal of the Council for Educational Technology》2020,51(5):1748-1765

Artificial intelligence tools for education (AIEd) have been used to automate the provision of learning support to mainstream learners. One of the most innovative approaches in this field is the use of data and machine learning for the detection of a student’s affective state, to move them out of negative states that inhibit learning, into positive states such as engagement. In spite of their obvious potential to provide the personalisation that would give extra support for learners with intellectual disabilities, little work on AIEd systems that utilise affect recognition currently addresses this group. Our system used multimodal sensor data and machine learning to first identify three affective states linked to learning (engagement, frustration, boredom) and second determine the presentation of learning content so that the learner is maintained in an optimal affective state and rate of learning is maximised. To evaluate this adaptive learning system, 67 participants aged between 6 and 18 years acting as their own control took part in a series of sessions using the system. Sessions alternated between using the system with both affect detection and learning achievement to drive the selection of learning content (intervention) and using learning achievement alone (control) to drive the selection of learning content. Lack of boredom was the state with the strongest link to achievement, with both frustration and engagement positively related to achievement. There was significantly more engagement and less boredom in intervention than control sessions, but no significant difference in achievement. These results suggest that engagement does increase when activities are tailored to the personal needs and emotional state of the learner and that the system was promoting affective states that in turn promote learning. However, longer exposure is necessary to determine the effect on learning.  相似文献   

Microfluidic-driven viral infection on cell cultures: Theoretical and experimental study     

Elisa Cimetta  Mauro Franzoso  Marta Trevisan  Elena Serena  Alessandro Zambon  Stefano Giulitti  Luisa Barzon  Nicola Elvassore 《Biomicrofluidics》2012,6(2):024127-12

Advanced cell culture systems creating a controlled and predictable microenvironment together with computational modeling may be useful tools to optimize the efficiency of cell infections. In this paper, we will present a phenomenological study of a virus-host infection system, and the development of a multilayered microfluidic platform used to accurately tune the virus delivery from a diffusive-limited regime to a convective-dominated regime. Mathematical models predicted the convective-diffusive regimes developed within the system itself and determined the dominating mass transport phenomena. Adenoviral vectors carrying the enhanced green fluorescent protein (EGFP) transgene were used at different multiplicities of infection (MOI) to infect multiple cell types, both in standard static and in perfused conditions. Our results validate the mathematical models and demonstrate how the infection processes through perfusion via microfluidic platform led to an enhancement of adenoviral infection efficiency even at low MOIs. This was particularly evident at the longer time points, since the establishment of steady-state condition guaranteed a constant viral concentration close to cells, thus strengthening the efficiency of infection. Finally, we introduced the concept of effective MOI, a more appropriate variable for microfluidic infections that considers the number of adenoviruses in solution per cell at a certain time.  相似文献   

Technology push and demand pull perspectives in innovation studies: Current findings and future research directions     

Giada Di Stefano  Alfonso Gambardella  Gianmario Verona 《Research Policy》2012,41(8):1283-1295

This study updates the debate on the sources of innovation. Using techniques like factor analysis, multidimensional scaling, and pathfinder analysis, we examine the most influential articles that have dealt with the topic. Our analysis provides three main findings. The first more precisely highlights the role of demand as a source of innovation. The second illustrates how competences enable firms to match technology with demand and capitalize on technology and demand as sources of innovation. The third unveils a distinction between external and internal sources of innovations. The sources of innovation can be purely external or internally generated competences that enable the firm to integrate external knowledge within its boundaries. Our work contributes to the classic debate by providing a more granular understanding of how technology and demand interact. In discussing our findings, we link our framework to strategy, innovation and entrepreneurship studies that expressly call for a better understanding of technology and demand factors in value creation and capture.  相似文献   

Return mobility and scientific productivity of researchers working abroad: The role of home country linkages   总被引：1，自引：0，他引：1  

Stefano H. Baruffaldi  Paolo Landoni 《Research Policy》2012,41(9):1655-1665

Through an analysis of 497 foreign researchers in Italy and Portugal we verify the impact of home linkages on return mobility choices and scientific productivity. We consider the presence of several different types of linkages of the researchers working abroad with their country of origin and control for the most relevant contextual factors (age, research area, position in the host country, etc.). The probability of return to their home country and scientific productivity in the host country are both higher for researchers that maintain home linkages. We conclude that the presence of home linkages directly benefits both countries in addition to the indirect benefit of expanding the scientific networks. Policy implications and suggestions for further research are discussed.  相似文献