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111.
Homework (HW) is one of the most common school-related activities among parents, students and teachers. However, the need to assign HW to students has been extensively debated. The present investigation examines the relationship between specific HW variables (i.e. amount of HW completed, time spent on HW and perceived quality of HW time management) and academic achievement, while controlling for students’ gender and grade level. Participants included 454 students (ranging from 10 to 16?years of age) from three schools in northern Spain. A multivariate analyses of variance and path analyses showed that the amount of HW completed decreased with increased schooling, as did students’ perceived quality of HW time management. Data from hierarchical regression analyses completed by path analyses provided evidence that time spent on HW conjointly with perceived quality of HW time management explains how academic achievement is mediated by the amount of HW completed. These findings deepen the understanding of the complex impact of time spent on HW and on academic achievement.  相似文献   
112.
This article focuses on the role of global universities and globalisations in an age of global interdependence and cosmopolitanism. Competing agendas that result from actions and reactions to multiple globalisations are considered in relation to global citizenship education. These agendas are crucial in understanding dilemmas of the local and the global in relation to education. Key emerging agendas are highlighted, including those of the hyperglobalisers, skeptics and transformationists. Three themes are central for this conversation, namely a) how multiple globalisations are impacting global life and academics, b) how networks have become privileged sites for global education, and c) the implications of globalisation and networks for global citizenship and global universities.  相似文献   
113.
Observations of the contemporary news media environment often revolve around the topics of ideological polarization and blurred boundaries between mass and interpersonal communication. This study explores these topics through a focus on the association between ideologically oriented online news use, commenting on online news, and political participation. We hypothesize that both ideological online news use generally and proattitudinal online news use are positively related to political participation and that online news commenting creates “differential gains” by augmenting these relationships. Yet we also hypothesize that counterattitudinal online news use is negatively related to political participation and that online news commenting creates “differential losses” by exacerbating this relationship. Analyses of two independently collected and nationally representative surveys found that frequent ideological online news use, proattitudinal online news use, and commenting are all positively related to political participation. We found no evidence for differential gains as a result of online commenting but only for differential losses—counterattitudinal online news use interacts with commenting to create a negative relationship with political participation.  相似文献   
114.
研究目的:优化获得血红密孔菌(P.sanguineus)的最佳培养基组成,提高耐热漆酶的产量。创新要点:获得了目前文献报道的最高水平的漆酶活力。研究方法:通过单因素试验研究了不同培养基(番茄汁、麦麸、麦芽提取物和葡萄糖细菌蛋白胨培养基)和不同组合诱导剂(大豆油、阿魏酸、没食子酸、二甲基苯胺、酸性蓝62和活性蓝19分别与硫酸铜组合诱导剂)对P.sanguineus产耐热漆酶的影响。在此基础上采用中心组合试验设计,进一步研究了番茄汁培养基结合硫酸铜和大豆油组合诱导剂对P.sanguineus产耐热漆酶的影响。利用SAS10.0和响应面分析方法对试验结果进行了统计分析和建立回归模型。重要结论:通过中心组合设计优化得出P.sanguineus产耐热漆酶的最优培养基条件:以36.8%番茄汁为培养基,以3 mmol/L硫酸铜和1%大豆油作为组合诱导剂。该条件下在10 L搅拌槽生物反应器中漆酶活力达到了143 000 IU/L(2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)为底物,pH值为3.0)。  相似文献   
115.
We develop natural language processing techniques to identify the creation and impact of new technologies in the population of U.S. patents. We validate the new techniques and their improvement over traditional metrics based on patent classification and citations in two case-control studies. First, we collect patents linked to awards such as the Nobel prize and the National Inventor Hall of Fame. These patents likely cover radically new technologies with a major impact on technological progress and patenting. Second, we identify patents granted by the United States Patent and Trademark Office but simultaneously rejected by both the European and Japanese patent office. Such patents arguably lack novelty or cover small incremental advances over prior art and should have little impact on technological progress. We provide open access to code, data, and new measures for all utility patents granted by the USPTO up to May 2018 (see https://zenodo.org/record/3515985, DOI: 10.5281/zenodo.3515985).  相似文献   
116.
117.
The purpose of the present study was to investigate the socio-demographic and lifestyle determinants of physical activity practice, as well as the motivations for being or not being physically active in Spanish university students. A representative sample of students from a Spanish university (n = 2,051; 42.1% males; mean age 21.9, s = 4.8 years) participated in the present cross-sectional study. A questionnaire including questions regarding lifestyle, dietary habits, parents' characteristics, and physical activity habits was administered to the students. The socio-demographic and lifestyle determinants of physical activity practice were assessed using multivariable logistic regression. 68.4% of men and 48.4% of women reported to practise physical activity in the present sample. Those who practised physical activity consumed more fruits and were less likely to be smokers compared to non-physically active students. Also, physically inactive men spent more time in front of the computer and physically inactive women spent more time in front of the TV and were more likely to be frequent alcohol consumers. Maternal educational level and maternal physical activity habits were also important determinants of physical activity practice among men and women respectively. In conclusion, physically active students tended to engage in other healthy habits in the present population, suggesting the clustering of healthy or unhealthy lifestyle factors among specific subgroups.  相似文献   
118.
This study seeks to discover whether handball goalkeepers employ a general anticipatory strategy when facing long distance throws and the effect of uncertainty on these strategies. Seven goalkeepers and four throwers took part. We used a force platform to analyse the goalkeeper's movements on the basis of reaction forces and two video cameras synchronised at 500 Hz to film the throw using 3D video techniques. The goalkeepers initiated their movement towards the side of the throw 193 ± 67 ms before the release of the ball and when the uncertainty was reduced the time increased to 349 ± 71 ms. The kinematics analysis of their centre of mass indicated that there was an anticipatory strategy of movement with certain modifications when there was greater uncertainty. All the average scores referring to velocity and lateral movement of the goalkeeper's centre of mass are significantly greater than those recorded for the experimental situation with bigger uncertainty. The methodology used has enabled us to tackle the study of anticipation from an analysis of the movement used by goalkeepers to save the ball.  相似文献   
119.
120.
The objective of this study is to analyze secondary school students' interactions (conflicts, controversies, and arguments) as they participate in an intact classroom activity designed to facilitate their understanding of heat energy and temperature. The study is based on 32 ninth-grade students in a public school in Londrina, Brazil. Results obtained show that the differentiation between heat energy and temperature constitutes considerable difficulties for the students, and can be considered as part of the hard-core of their understanding (Lakatos, 1970, Criticism and the Growth of Knowledge, Cambridge University Press, Cambridge, UK, pp. 91–196). Student interactions (video taped) were classified into an Alternative Model, Transitional Model, and Scientific Model, depending on the degree to which they reflected a progressive transition in their hard-core. Students generally resisted a change in their conceptual understanding. Some students were able to question the hard-core of their beliefs and construct a Transitory Model. Some students experienced a further progressive transition by constructing a Scientific Model, based on the understanding that Temperature only measures the energy of agitation. Methodology used also provided a glimpse of how a particular student grappled with the conflicts in order to facilitate progressive transition in understanding. It is concluded that given the opportunity to discuss, reflect, consider alternative/conflicting situations, students can construct models that increase progressively in their heuristic/explanatory power.  相似文献   
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