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911.
Genetic engineering: A matter that requires further refinement in Spanish secondary school textbooks
M. V. Martínez-Gracia M. J. Gil-Quýlez J. Osada 《International Journal of Science Education》2013,35(9):1148-1168
Genetic engineering is now an integral part of many high school textbooks but little work has been done to assess whether it is being properly addressed. A checklist with 19 items was used to analyze how genetic engineering is presented in biology textbooks commonly used in Spanish high schools, including the content, its relationship with fundamental genetic principles, and how it aims to improve the genetic literacy of students. The results show that genetic engineering was normally introduced without a clear reference to the universal genetic code, protein expression or the genetic material shared by all species. In most cases it was poorly defined, without a clear explanation of all the relevant processes involved. Some procedures (such as vectors) were explained in detail without considering previous student knowledge or skills. Some books emphasized applications such as the human genome project without describing DNA sequencing. All books included possible repercussions, but in most cases only fashionable topics such as human cloning. There was an excess of information that was not always well founded and hence was unsuitable to provide a meaningful understanding of DNA technology required for citizens in the twenty-first century. 相似文献
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913.
A new residential college and a faculty-in-residence program demonstrate how student affairs educators and academic faculty at one institution have collaborated to create transformational learning experiences for their students. 相似文献
914.
Belinda V. de Castro 《Asia Pacific Education Review》2008,9(2):101-112
This quasi-experimental study aims to streamline cognitive models on fraction multiplication and division that contain the
most worthwhile features of other existing models. Its exploratory nature and its approach to proof elicitation can be used
to help establish its effectiveness in building students’ understanding of fractions as compared to the traditional algorithmic
way of teaching, vis-à-vis the students’ negative notions about learning fractions. Interestingly, the study showed the benefits
and drawbacks of using these cognitive models in the teaching and learning of mathematics. 相似文献
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Development of a test device for testing soccer boots under gamerelevant highrisk loading conditions
Soccer boots are the most important piece of equipment used by a soccer player. They have been improved from heavy bold leather
shoes to lightweight aerodynamic designer objects. As traction is one of the key factors of performance, industry experiments
with new stud designs, hoping to improve traction behaviour in the different directions. However, excessive traction may contribute
to the occurrence of non-contact injuries of the anterior cruciate ligament (ACL). Therefore, many researchers have investigated
the shoe-surface interaction of studded boots with mechanical test devices. As yet, a final conclusion regarding correlation
between stud design and ACL injuries has not been obtained. Most of the current test devices do not test the soccer boots
under game-relevant loading conditions. A new approach has been taken in order to overcome this limitation. In the first step,
real ACL injury situations were analysed in detail. The results of this analysis were then used as input data for a multi-body
computer model of the human body, to calculate internal forces at the injured leg. Based on this data, a new test device,
the TrakTester, was developed including an artificial lower leg with a replica human ankle joint. This paper presents details
of the development of the new traction test device and gives an overview of the research options the TrakTester may provide
for the future. 相似文献
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