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121.
Dimov N Muñoz L Carot-Sans G Verhoeven ML Bula WP Kocer G Guerrero A Gardeniers HJ 《Biomicrofluidics》2011,5(3):34102-3410212
To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS). 相似文献
122.
Pereira G Correia R Ugrinowitsch C Nakamura F Rodacki A Fowler N Kokubun E 《Journal of sports sciences》2011,29(9):927-932
The aims of this study were (a) to assess the ability of the rating of perceived exertion (RPE) to predict performance (i.e. number of vertical jumps performed to a fixed jump height) of an intermittent vertical jump exercise, and (b) to determine the ability of RPE to describe the physiological demand of such exercise. Eight healthy men performed intermittent vertical jumps with rest periods of 4, 5, and 6 s until fatigue. Heart rate and RPE were recorded every five jumps throughout the sessions. The number of vertical jumps performed was also recorded. Random coefficient growth curve analysis identified relationships between the number of vertical jumps and both RPE and heart rate for which there were similar slopes. In addition, there were no differences between individual slopes and the mean slope for either RPE or heart rate. Moreover, RPE and number of jumps were highly correlated throughout all sessions (r = 0.97-0.99; P < 0.001), as were RPE and heart rate (r = 0.93-0.97; P < 0.001). The findings suggest that RPE can both predict the performance of intermittent vertical jump exercise and describe the physiological demands of such exercise. 相似文献
123.
Cañal-Bruland R Mooren M Savelsbergh GJ 《Research quarterly for exercise and sport》2011,82(4):667-674
In this study, we examined how perceptual-motor expertise and watching experience contribute to anticipating the outcome of opponents' attacking actions in beach volleyball. To this end, we invited 8 expert beach volleyball players, 8 expert coaches, 8 expert referees, and 8 control participants with no beach volleyball experience to watch videos of attack sequences that were occluded at three different times and to predict the outcome of these situations. Results showed that expert players and coaches (who were both perceptual-motor experts) outperformed the expert referees (who were watching experts but did not have the same motor expertise) and the control group in the latest occlusion condition (i.e., at spiker-ball contact). This finding suggests that perceptual-motor expertise may contribute to successful action anticipation in beach volleyball. 相似文献
124.
Anna Cigarini Isabelle Bonhoure Julián Vicens Josep Perelló 《Library & information science research》2021,43(2):101090
Can public libraries become hubs for citizen science? In line with the principles of citizen science, this question was answered collaboratively with librarians from the Barcelona Network of Public Libraries who performed two hands-on activities. One activity was a training course taken by 30 librarians from 24 different libraries which enabled them to envisage citizen science implementation at each library. The other activity consisted of co-creating a citizen social science project and involved 40 library users, seven librarians from three different cities, and professional scientists. The analysis considers the perspectives of both librarians and users, through participant observation, surveys, and a focus group to identify strengths and challenges. The overall results suggest that public libraries can offer leadership in the promotion of citizen science and contribute to the mission of public libraries to act as local community hubs. The main challenges identified were related to the complexity of collaboration, uncertainty regarding research co-creation, and participant retention strategies. 相似文献
125.
In this paper, we explore how local governments are using Instagram as a communication tool to engage with their citizens, using data from the municipalities of Andalusia (Spain). We seek to identify the determinants of local government use of Instagram, the determinants of activity in this channel and the determinants of citizen reactions in order to understand the influence of media types (picture, video or album) used in municipality posts, and to understand content type (what the post is about). Instaloader, an open source intelligence (OSINT) tool for Instagram, was applied. It made it possible to automatically extract all posts of the analysed municipalities (14,742 posts). These were later automatically analysed using R, an open source software. It was determined that of the 29 Andalusian local governments with the highest populations, only those that maintain an account on Instagram, totalling 17 municipalities (58.62%), would be part of the final analysis. Our findings demonstrate that when local governments have a high level of debt, they do not maintain and actively use Instagram accounts. We also found that quality of posts’ content is more important than quantity of followers, since there is no significant relationship between citizen reactions and the number of inhabitants of a municipality or the number of followers (audience), while there is a significant negative relationship between the number of posts (activity) and reactions. Our results also highlight that the level of reactions can be stimulated by certain media and content types. 相似文献
126.
Seckel María José Vásquez Claudia Samuel Marjorie Breda Adriana 《Education and Information Technologies》2022,27(3):2955-2975
Education and Information Technologies - Computational thinking in the educational environment has awaken a rising interest, having been included as part of the curricula from the very beginnings... 相似文献
127.
Kwok Andrew Keese Jeffrey Suárez Mario I. Mitchell Douglas Huston Debbee 《Learning Environments Research》2022,25(1):255-270
Learning Environments Research - The pedagogical beliefs of novice teachers and their coaches throughout a two-year induction program and how those beliefs impact their induction experiences were... 相似文献
128.
Miguel Á. Conde Francisco J. García-Peñalvo María J. Rodríguez-Conde Marc Alier María J. Casany Jordi Piguillem 《Interactive Learning Environments》2014,22(2):188-204
The tools used in learning processes are in a continuous state of flux. One of the most significant changes is the application of Information and Communications technologies (ICTs) to educational contexts. This provides new possible ways to carry out learning activities, new learning services, the possibility to use new kinds of contents and activities, etc. However, ICTs have not provided as many advantages as they were supposed to, so changes are necessary. In this context, a new set of tools, Web 2.0, offers a new way to understand the Web, in which the user is the centre. Further, users can cooperate in order to define contents. This concept is also applied in technology-mediated learning but there are important problems when one tries to integrate such tools and concepts with existing systems. This paper explores the integration of these tools in traditional learning environments, the various possibilities and their advantages and drawbacks. After that, an interoperability scenario is described and two experiences are presented to show how 2.0 tools can be integrated in learning activities, and its effect in educational process. 相似文献
129.
Research results of two personal learning environments experiments in a higher education institution
Victoria Marín Juarros Jesús Salinas Ibáñez Bárbara de Benito Crosetti 《Interactive Learning Environments》2014,22(2):205-220
This paper focuses on institutionally powered personal learning environments (iPLEs). The concept of the iPLE can be seen as a way universities can incorporate learner-centred approach into the architecture of their technology-enhanced learning environments. The aim of this paper is to pose that there are other ways to learn complementary to virtual learning environments, such as using distributed Web 2.0 tools from personal learning environments (PLEs). With that aim in mind, this paper presents an exploratory study with two different iPLE configurations, analyses how they modify the learning–teaching process, and reports their perceived usefulness from the students' point of view. These two case studies were carried out by a research group of educational technology from a Spanish university in graduate and postgraduate courses. As reported by other case studies, the results revealed that students use the environment basically in the academic context and this usage is conceived as another time and effort requiring task. This fact can be observed in the low level iPLEs customization. The overall conclusions we can extract are, on the one hand, that the new environment to integrate informal and formal learning should be flexible and adaptable to the student's needs and preferences and, on the other hand, that academic tools might someday become personal tools. 相似文献
130.
Fátima Viteri Geraldine Clarebout Marion Crauwels 《Environmental Education Research》2014,20(2):228-247
This study examined recall (Rcl) differences of high, average and low achieving fifth-grade elementary students (72) for an environmental education video with supporting pedagogical materials. In addition, it assessed the motivational level of all students. Recall assessment was carried out one-week and twenty-weeks after intervention. Main findings suggest comparative Rcl results for all achievers and high motivation for the designed video and pedagogical materials. Implications for future research and for an integrative materials’ design approach are presented. 相似文献