A concept map approach to developing collaborative Mindtools for context‐aware ubiquitous learning

Recent advances in mobile and wireless communication technologies have enabled various new learning approaches which situate students in environments that combine real‐world and digital‐world learning resources; moreover, students are allowed to share knowledge or experiences with others during the learning process. Although such an approach seems to be promising and innovative, researchers have indicated several problems when applying it to practical applications, in particular, the lack of proper strategies or tools to assist the students to learn collaboratively in such a learning scenario with abundant content. Students might feel interested when using the mobile devices to learn; however, without proper assistance or guidance, their learning achievements are usually disappointing. To cope with this problem, this study proposes a concept map‐oriented Mindtool for collaborative ubiquitous learning. Experimental results from a natural science course in an elementary school show that this approach not only enhances learning motivation but also improves the learning achievements of the students.     

技术并不会消除数字鸿沟

最近几年,像美国许多城市一样,莫德斯托(Modesto)也一直遭到媒体裁员和开支削减的冲击.记者的责任比从前更大了,他们越来越多地依靠微博、Facebook、博客、谷歌等采集新闻和报道.在这种数字转变之前,记者对美国贫穷的工人阶级的报道不仅偏少而且往往是脸谱化的或遭到扭曲的.如今,社交媒体使更多公民参与到地方新闻的制作和传播中来.这种新平台能帮助被边缘化的声音更好地在媒体上展现吗?     

Three-dimensional cellular focusing utilizing a combination of insulator-based and metallic dielectrophoresis

Particle focusing in microfluidic devices is a necessary step in medical applications, such as detection, sorting, counting, and flow cytometry. This study proposes a microdevice that combines insulator-based and metal-electrode dielectrophoresis for the three-dimensional focusing of biological cells. Four insulating structures, which form an X pattern, are employed to confine the electric field in a conducting solution, thereby creating localized field minima in the microchannel. These electrodes, 56-μm-wide at the top and bottom surfaces, are connected to one electric pole of the power source. The electrodes connected to the opposite pole, which are at the sides of the microchannel, have one of three patterns: planar, dual-planar, or three-dimensional. Therefore, low-electric-field regions at the center of the microchannel are generated to restrain the viable HeLa cells with negative dielectrophoretic response. The array of insulating structures aforementioned is used to enhance the performance of confinement. According to numerical simulations, three-dimensional electrodes exhibit the best focusing performance, followed by dual-planar and planar electrodes. Experimental results reveal that increasing the strength of the applied electric field or decreasing the inlet flow rate significantly enhances focusing performance. The smallest width of focusing is 17 μm for an applied voltage and an inlet flow rate of 35 V and 0.5 μl/min, respectively. The effect of the inlet flow rate on focusing is insignificant for an applied voltage of 35 V. The proposed design retains the advantages of insulator-based dielectrophoresis with a relatively low required voltage. Additionally, complicated flow controls are unnecessary for the three-dimensional focusing of cells.     

Nutrition guidelines for strength sports: sprinting, weightlifting, throwing events, and bodybuilding

Strength and power athletes are primarily interested in enhancing power relative to body weight and thus almost all undertake some form of resistance training. While athletes may periodically attempt to promote skeletal muscle hypertrophy, key nutritional issues are broader than those pertinent to hypertrophy and include an appreciation of the sports supplement industry, the strategic timing of nutrient intake to maximize fuelling and recovery objectives, plus achievement of pre-competition body mass requirements. Total energy and macronutrient intakes of strength-power athletes are generally high but intakes tend to be unremarkable when expressed relative to body mass. Greater insight into optimization of dietary intake to achieve nutrition-related goals would be achieved from assessment of nutrient distribution over the day, especially intake before, during, and after exercise. This information is not readily available on strength-power athletes and research is warranted. There is a general void of scientific investigation relating specifically to this unique group of athletes. Until this is resolved, sports nutrition recommendations for strength-power athletes should be directed at the individual athlete, focusing on their specific nutrition-related goals, with an emphasis on the nutritional support of training.     

African American preschool children's physical activity levels in Head Start

The purpose of this study was to describe the physical activity levels of urban inner city preschoolers while attending Head Start, the federally funded preschool program for children from low-income families. Participants were 158 African American children. Their physical activity during Head Start days was measured using programmed RT-3 accelerometers. Results revealed that the children spent the most time in sedentary and light physical activity, while their participation in moderate-to-vigorous physical activities was low. Given the sedentary class format and limited physical space for the Head Start programs observed, we suggest adding a structured physical activity component to Head Start schools to fight the overweight and obesity crisis.     

Before,During, and After Examination: Development of Prospective Preschool Teachers’ Mathematics-Related Enjoyment and Self-Efficacy

This article examines the stability of Norwegian prospective preschool teachers’ enjoyment of mathematics and their mathematics-related self-efficacy before, during, and after a teacher-education examination. In addition, the stability of the two constructs across countries was examined through a comparison with Germany. The data revealed partial stability (technically speaking, metric invariance) of enjoyment but not of self-efficacy. Self-efficacy increased significantly before and after the examination without decreasing enjoyment, which may be a result of increased learning time. Prior mathematical knowledge predicted the level and development of enjoyment and self-efficacy in both countries. Many Norwegian students reported low mathematics-related enjoyment and self-efficacy, including negative developments. It may be important to provide positive experiences of mathematical activities during preschool teacher education.     

Can typical game features have unintended consequences? A study of players’ learning and reactions to challenge and failure in an educational programming game

It is difficult to motivate learners to seek out and persist at challenging learning tasks where failure is likely. However, in game environments, people seem highly motivated to engage with challenges and respond productively to failure. Many typical game features purportedly enhance intrinsic motivation and self-efficacy, which should improve students’ reactions to challenge and failure, which should in turn enhance learning. An experimental study with early middle school students tested these assumptions by comparing a “Full” version of a typical, commercial programming game to a “Minimal” version of the same game where common game features such as narrative, performance metrics, high-quality graphics, and sound were removed. In contrast to our hypotheses, players of the Full Game were less likely to choose coding challenges, were less tolerant of coding failures and gained less coding knowledge. Intrinsic motivation and self-efficacy did not differ between conditions. Correlational analyses showed that failure tolerance and challenge seeking may critically affect learning from educational games. The current study offers an existence proof that some common game features can hinder players' failure tolerance, challenge-seeking and learning, in certain game contexts. Future research should isolate the effects of individual game features, test generalizability and explore which contextual variables influence the findings.