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131.
Although the presence of toys in childhood has remained steady for decades, the types of toys that fill children's toy boxes have changed, especially over the last 10–15 years. Many of today's toys are marked by technological enhancements, from a shape sorter driven by a singing bear to robotic plastic animals designed to match a toddler's favorite television show. Although examining the effects of these changes is still an unexplored area, research to date suggests that there may be costs to the quality of caregiver–child interaction when using these toys together. This leads to two possibilities: (1) the design of the enhancements themselves hurt interactions; or (2) these toys can still be beneficial to interactions, but caregivers simply need to be aware of the potential pitfalls. In this study, we explore whether providing caregivers with a subtle cue about the potential negative impacts of technological toys on caregiver–child interaction affects their behavior.  相似文献   
132.
In recent years, there has been a strong push to transform STEM education at K-12 and collegiate levels to help students learn to think like scientists. One aspect of this transformation involves redesigning instruction and curricula around fundamental scientific ideas that serve as conceptual scaffolds students can use to build cohesive knowledge structures. In this study, we investigated how students use mass balance reasoning as a conceptual scaffold to gain a deeper understanding of how matter moves through biological systems. Our aim was to lay the groundwork for a mass balance learning progression in physiology. We drew on a general models framework from biology and a covariational reasoning framework from math education to interpret students' mass balance ideas. We used a constant comparative method to identify students' reasoning patterns from 73 interviews conducted with undergraduate biology students. We helped validate the reasoning patterns identified with >8000 written responses collected from students at multiple institutions. From our analyses, we identified two related progress variables that describe key elements of students' performances: the first describes how students identify and use matter flows in biology phenomena; the second characterizes how students use net rate-of-change to predict how matter accumulates in, or disperses from, a compartment. We also present a case study of how we used our emerging mass balance learning progression to inform instructional practices to support students' mass balance reasoning. Our progress variables describe one way students engage in three dimensional learning by showing how student performances associated with the practice of mathematical thinking reveal their understanding of the core concept of matter flows as governed by the crosscutting concept of matter conservation. Though our work is situated in physiology, it extends previous work in climate change education and is applicable to other scientific fields, such as physics, engineering, and geochemistry.  相似文献   
133.
This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal and spatial movement is highly predictable and that the majority of calls and text messages are sent to only four to six different persons. This article extends this research by examining both tie strength and the distance between the interlocutors in urban and rural settings. The findings show that even as information and communication technologies (ICTs) potentially put the world at our fingertips, the mobile phone is an instrument of a more limited geographical and social sphere. Approximately two-thirds of our calls/texts go to strong ties that are within a 25-km radius.  相似文献   
134.
Prediction markets designed to predict terrorism through traders’ investments on the likelihood of specific terrorist attacks are, strictly speaking, enabling those traders to bet on terrorism. Betting on terrorist attacks, like some other forms of betting on death, has been accused of being repugnant. In this paper, it is argued that while government-backed effective intelligence-gathering prediction markets on terrorism (PMsoT) might elicit feelings of repugnance, those feelings are likely to be misguided. The feelings of repugnance arise because PMsoT are assumed to be associated with terrorism in encouraging and endorsing ways and with human death in a disrespectful way. However, it is argued that these feelings of repugnance are misguided in the case of government-backed effective intelligence-gathering PMsoT because the purpose and effect of such prediction markets, and (on balance) the trading they encourage, is to prevent and renounce terrorism and show respect for matters of life and death.  相似文献   
135.
It's something they can relate to. You know, assimilate. They go there, talk in Spanish, not worry about it, drink, have fun, do it all in a language they're accustomed to, or at least with people they feel more comfortable with. I guess that's why a lot of them come Monday nights from these distances. That's what I was trying to explain to Chris. If you have a Latino night it's going to be successful because us as Latinos don't have a lot of options for us to go or places for us to go.  相似文献   
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