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1.
The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L).  相似文献   
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ABSTRACT

We present Mobile Augmented-Reality Games for Instructional Support (MAGIS), a framework for the development of mobile augmented-reality (AR) games for education. The framework supports off-the-shelf, state-of-the-art technologies that enable AR tracking and rendering on consumer-level mobile devices, and integrates these technologies with content-generation tools that simplify the development of educational AR games, especially those that extensively use narrative-based game design and player-location tracking such as location-based historical or museum adventure games. We use Igpaw: Intramuros, a proof-of-concept game developed using MAGIS, to help describe the current state of the framework and to show its efficacy for implementing outdoor location-based educational games, and we briefly outline future development plans to improve MAGIS’ AR support (especially those involving indoor scenarios) as well as to improve the instructional design and authoring phases of AR applications written using this framework.  相似文献   
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While there is evidence of the growing popularity of iPads and other tablets in K–12 education, little is understood about how teachers use these devices in their instruction. This study examines 342 teachers' comfort level with and perception toward iPad use and any changes that occurred over the implementation year. Using a mixed-methods design, this study found significant differences in comfort level by years of teaching and school levels. Female teachers, teachers with 20 years or less of teaching experience, and elementary school teachers were more positive about their perception toward iPad use than the other groups. High school teachers' perception was the lowest overall. Analyses of teacher interviews revealed affordances, challenges, and diverse ways of how teachers used iPads in their instruction. Implications for practice and research are discussed.  相似文献   
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The election of Raúl Alfonsín in October of 1983 represented the return of democracy to Argentina after more than seven years of a military dictatorship that left the country in a terribly distressed state. Since the dictatorship had joined the boycott of the 1980 Moscow Olympics led by the USA, for Argentina, the 1984 Los Angeles Olympics meant both coming back to the Olympic fold and the first such festival under the new democratic government. This paper explores Argentina's trajectory towards, and construction of, its participation in the country's first post-dictatorship Olympics. In doing so, this paper reveals why participation in the 1984 Los Angeles Olympics was not a priority for the incoming administration and why such participation was not conceived as a potential emissary capable of reaffirming on the global Olympic stage the hard fought, yet still emerging, democracy of Argentina. In addition, it reveals not only the determination of the Alfonsín administration to make his sport policy work but also its aspirations, complexity and ambiguities.  相似文献   
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Reform efforts have emphasized the need to support teachers' learning about reform‐oriented practices. Educative curriculum materials are one potential vehicle for promoting teacher learning about these practices. Educative curriculum materials include supports that are intended to promote both student and teacher learning. However, little is known about the extent to which existing curriculum materials provide support for teachers and the ways they can be improved. In this study, eight sets of high school biology curriculum materials were reviewed to determine their potential for promoting teacher learning. Design heuristics for educative curriculum materials were adapted for use as evaluation criteria. From this analysis, several themes emerged. First, the materials tended to provide support for teachers' subject matter knowledge and pedagogical content knowledge for students' ideas (e.g., misconceptions) but rarely for their pedagogical content knowledge of scientific inquiry. Second, the materials contained several implementation guidance supports but far fewer rationales for instructional decisions, which are an important feature of educative curriculum materials. Finally, the quality of support varied widely, differing in its degree of relevance, pedagogical helpfulness, and depth. The article concludes with recommendations for the redesign of existing curriculum materials. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 46: 977–998, 2009  相似文献   
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Tensiomyography has been suggested as an indirect marker of muscle stiffness, which is associated with strength/power performance. Therefore, it is reasonable to suggest that tensiomyography parameters could be associated with power-related motor tasks. The purpose of this study was to investigate the association between tensiomyography parameters (from rectus and biceps femoris) and jumping and sprinting abilities in elite soccer players. In addition, we used tensiomyography parameters to compare the lateral symmetry between dominant and non-dominant legs. Twenty elite soccer players (age: 23.3 ± 4.8 years; height: 183.5 ± 6.6 cm; weight: 77.8 ± 7.5 kg) volunteered to participate in the study. Significant moderate negative correlations between biceps femoris displacement and contact time (r = –0.5, p = 0.03), rectus femoris displacement and contact time (r = –0.51, p = 0.02), and a significant moderate correlation between biceps femoris displacement and reactive strength index (r = 0.5, p = 0.03) were found. There were no correlations between tensiomyography parameters and power-related motor tasks. In addition, no differences in tensiomyography parameters between dominant and non-dominant legs were found. Our data suggest that tensiomyography parameters are not associated with power-related motor tasks performance in elite soccer players.  相似文献   
10.
Abstract

Despite frequent claims that invasive methods of sex verification and early procedures for doping detection were used in 1966 and 1967 at different major international sport competitions, little is known about the origins and rationales for implementing such procedures. This paper focuses on the drug testing and sex verification protocols implemented at the 1967 Pan-American Games held in Winnipeg. Specifically, it explores the conditions that led to these protocols, as well as the details of and the arguments invoked for their implementation. To do so, archival material, media coverage featured in English, French, Portuguese, and Spanish newspapers and magazines across the Americas, and oral histories are analyzed and discussed. The paper demonstrates that neither the sex verification nor the drug testing protocol was mandatory for all athletes and only two very specific groups of athletes were targeted. It also demonstrates that in the case of the former, exceptions were made within the specific group targeted. The paper concludes that the rudimentary protocols applied at the 1967 Pan-American Games likely informed the IOC Medical Commission’s doping and sex-testing policies implemented at the 1968 Mexico City Olympics and Grenoble Winter Olympics.  相似文献   
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