加拿大英语的保守性特点及其成因

加拿大英语除了具有鲜明的创新性特点以外,其保守性特点也很突出。18世纪末英国殖民者将当时的英语带到北美。随着时代的变迁,英语在祖国发生了变化,但大洋彼岸因种种因素没有发生同样的变化。因此在今天的加拿大英语中却仍可寻到昔日英国英语的痕迹。这在语音、词汇和语法方面均有体现。加拿大英语保守性特点的成因主要有语言接触因素、社会因素和移民源的心理因素。通过对加拿大英语保守性特点及其成因的分析,有助于英语的学习与传播。     

Modelling home advantage in the Summer Olympic Games

Home advantage in team games is well proven and the influence of the crowd upon officials' decisions has been identified as a plausible cause. The aim of this study was to assess the significance of home advantage for five event groups selected from the Summer Olympic Games between 1896 and 1996, and put home advantage in team games in context with other sports. The five event groups were athletics and weightlifting (predominantly objectively judged), boxing and gymnastics (predominantly subjectively judged) and team games (involving subjective decisions). The proportion of points won was analysed as a binomial response variable using generalized linear interactive modelling. Preliminary exploration of the data highlighted the need to control for the proportion of competitors entered and to split the analysis pre- and post-war. Highly significant home advantage was found in event groups that were either subjectively judged or rely on subjective decisions. In contrast, little or no home advantage (and even away advantage) was observed for the two objectively judged groups. Officiating system was vital to both the existence and extent of home advantage. Our findings suggest that crowd noise has a greater influence upon officials' decisions than players' performances, as events with greater officiating input enjoyed significantly greater home advantage.     

Systematic characterization of degas-driven flow for poly(dimethylsiloxane) microfluidic devices

Degas-driven flow is a novel phenomenon used to propel fluids in poly(dimethylsiloxane) (PDMS)-based microfluidic devices without requiring any external power. This method takes advantage of the inherently high porosity and air solubility of PDMS by removing air molecules from the bulk PDMS before initiating the flow. The dynamics of degas-driven flow are dependent on the channel and device geometries and are highly sensitive to temporal parameters. These dependencies have not been fully characterized, hindering broad use of degas-driven flow as a microfluidic pumping mechanism. Here, we characterize, for the first time, the effect of various parameters on the dynamics of degas-driven flow, including channel geometry, PDMS thickness, PDMS exposure area, vacuum degassing time, and idle time at atmospheric pressure before loading. We investigate the effect of these parameters on flow velocity as well as channel fill time for the degas-driven flow process. Using our devices, we achieved reproducible flow with a standard deviation of less than 8% for flow velocity, as well as maximum flow rates of up to 3 nL∕s and mean flow rates of approximately 1-1.5 nL∕s. Parameters such as channel surface area and PDMS chip exposure area were found to have negligible impact on degas-driven flow dynamics, whereas channel cross-sectional area, degas time, PDMS thickness, and idle time were found to have a larger impact. In addition, we develop a physical model that can predict mean flow velocities within 6% of experimental values and can be used as a tool for future design of PDMS-based microfluidic devices that utilize degas-driven flow.     

Community involvement in research as a formal and informal mechanism for science education: Project Egret Watch

Specializations: science and environmental education, biology of herons.     

Do judges enhance home advantage in European championship boxing?

There have been many examples of contentious points decisions in boxing. Professional boxing is scored subjectively by judges and referees scoring each round of the contest. We assessed whether the probability of a home win (and therefore home advantage) increased when bouts were decided by points decisions rather than knockouts. Overall, we found that bouts ending in points decisions had a significantly higher proportion of home wins than those decided by a knockout, though this effect varied across time, and controlling for relative quality of boxers was only effective when using more recent data. Focusing on these data, again the probability of a home win was higher with a points decision and this effect was consistent as “relative quality” varied. For equally matched boxers (“relative quality” = 0), expected probability of a home win was 0.57 for knockouts, 0.66 for technical knockouts and 0.74 for points decisions. The results of the present study lend general support to the notion that home advantage is more prevalent in sports that involve subjective decision-making. We suggest that interventions should be designed to inform judges to counter home advantage effects.     

Consistency in teachers’ judgments

Professional teachers at first stage of secondary school were asked to assess the relative weights of five dimensions that in Italy must be considered when the final grades of students are decided. The teachers were also asked to give an overall evaluation of two samples of typical (i.e., students who record similar performances on all the dimensions) vs. atypical students (i.e., students who exhibit poor performance on at least one dimension and good or excellent performances on the others). The results show that the teachers shared a weighting scheme for assessment of the importance of the five dimensions. However, their overall evaluations were consistent with this weighting scheme only with reference to typical students. When the teachers evaluated atypical students, their judgements were highly inconsistent. The paper briefly discusses the implications of these findings.