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151.
This study was designed to contribute to a small but growing body of knowledge on the influence of gender in technology-rich collaborative learning environments. The study examined middle school students attitudes towards using computers and working in groups during scientific inquiry. Students attitudes towards technology and group work were analyzed using questionnaires. To add depth to the findings from the survey research, the role of gender was also investigated through the analysis of student conversations in the context of two activities: exploring science information on a hypertext text and conducting hands-on investigations. The data suggest that not only are girls and boys are similar with regard to attitudes about computers and group work, but that during collaborative learning activities, girls may actually participate more actively and persistently regardless of the nature of the task.  相似文献   
152.
INTRODUCTION Livestock is one of the largest sources of meth-ane emission with 80~115 million tons produced peryear, equivalent to 15%~20% of total anthropogenicmethane (IPCC, 2001). The global cattle population isresponsible for 73% of methane emissions of alllivestock, and methane produced during ruminalfermentation represents a loss of 2%~15% of grossenergy intake and may contribute to global warming(Johnson and Johnson, 1995). Many researches hadbeen carried out to find ways to low…  相似文献   
153.
Conclusions We are living a deep change in the information transfer process involving the different actors of the editorial scene (from authors to editors, web-editors, e-publishers and readers), who occasionally play different roles at the same time (e.g., authors sometimes bypass the editor thus assuming direct responsibilities in the diffusion of documents in the Internet). Furthermore, information producers, managers or seekers often show twofold personalities like Dr. Jekyll and Mr. Hyde. They would like to find all documents free on the Internet and be able to read original, reliable, and high quality information, but they are sometimes reluctant to spread their papers through online nonofficial channels as they care for the impact factor, prestige, and career advancement. It is a revolutionary period in which new and alternative forms of scholarly communication live together with more traditional ones and the future is difficult to define. Recent initiatives of open access—such as Pubmed Central, Public Library of Science, Budapest Open Access Initiative—are contributing to define new trends in the editorial market, challenging the traditional distribution channels, mainly managed by commercial editors, and placing the authors’ role and publication copyrights under severe discussion. In this landscape, GL now has new dignity and becomes closer and closer to innovative scientific publications supported by researchers in view of a generalised movement towards open access. The nuances of grey are becoming lighter and lighter. The questions are many, the answers few, but, in any case, the ethical responsibility of producing and issuing quality documents can never be disregarded.  相似文献   
154.
Thirteen Ph.D. students took part in interviews focussed on the nature of their own learning of mathematics. In analysing these interviews an unexpected category emerged concerning the students awareness of others as having particular types of learning goal. In this paper we explore the three levels which we discerned within this category and link them to the notion of cognitive empathy. We suggest that differences in ones own cognitive style are linked to differences in the ability to empathise with those who have alternative learning goals. We also consider how these two features – cognitive style and cognitive empathy – may come to be linked.  相似文献   
155.
Luciferase from firefly lantern extract was immobilized on CNBr-activated Sepharose 4B. The kinetic properties of immobilized luciferase were extensively studied. TheK m′ for D-luciferin is 11.9 μmol/L, the optimum pH and temperature for Sepharose-bound enzyme were 7.8 and 25°C respectively. A luminescence fiber optic biosensor, making use of immobilized crude luciferase, was developed for assay of ATP. The peak light intensity was linear with respect to ATP concentration in range of 10−9–10−5 mol/L. A biological application was also demonstrated with the determination of serum ATP from rats bred in low versus normal oxygen environments.  相似文献   
156.
Research shows that formative assessment can exert a powerful effect on student learning, yet the complexity of formative assessment is not well understood and some curricular structures and practices do not fully exploit its potential. This article outlines the background to the political promotion of employability and shows that institutional responses are influenced by multiple considerations. It discusses formative assessment and models it as a complex signalling system before considering the implications, for students’ employability, of accentuating the attention given to formative assessment. The potential for action is discussed with reference to three levels: those of the institution, the department, and the individual academic.  相似文献   
157.
Beno?t Godin 《Minerva》2012,50(4):397-421
Innovation has become a very popular concept over the twentieth century. However, few have stopped to study the origins of the category and to critically examine the studies produced on innovation. This paper conducts such an analysis on one type of innovation, namely technological innovation. The study of technological innovation is over one hundred years old. From the early 1900s onward, anthropologists, sociologists, historians, and economists began theorizing about technological innovation, each from his own respective disciplinary framework. However, in the last forty years an economic and ??dominant?? understanding of technological innovation has developed: technological innovation defined as commercialized invention. This paper documents the origins of this representation and the tradition of research to which it gave rise: ??innovation studies.?? More specifically, it analyzes what distinguishes this tradition from that concerned with technological change as the use of inventions in industrial production, and looks at why such a tradition originated in Europe.  相似文献   
158.
In this essay, I argue that popular entertainment can be understood in terms of Husserl’s concepts of epochē, reduction and constitution, and, conversely, that epochē, reduction and constitution can be explicated in terms of popular entertainment. To this end I use Husserl’s concepts to explicate and reflect upon the psychological and ethical effects of an exemplary instance of entertainment, the renowned Star Trek episode entitled “The Measure of a Man.” The importance of such an exercise is twofold: (1) to demonstrate, once again, the fecundity of the methodological procedures Husserl bequeathed to us; more than any other philosopher, he tapped into the fundamental manners in which we lose, make and remake the meanings of our lives; and (2) to demonstrate how popular entertainment, similarly, plays a central role in the making and remaking of the meanings of our lives. If my zig-zag procedure between Husserl’s philosophy and popular entertainment is productive and cogent, in addition to elucidating Husserl’s philosophy, it will demonstrate the reality-generating potency and the constitutive power of entertainment in the contemporary world. Entertainment, via ourselves, has become the primary producer of the meanings via which consciousness constitutes the world.  相似文献   
159.
In this work,the dynamic properties of composite cemented clay under a wide range of strains were studied considering the effect of different mixing ratio and the change of confining pressures through dynamic triaxial test. A simple and practical method to estimate the dynamic elastic modulus and damping ratio is proposed in this paper and a related empirical normalized formula is also presented. The results provide useful guidelines for preliminary estimation of cement requirements to improve the dynamic properties of clays.  相似文献   
160.
With the flooding of pornographic information on the Internet, how to keep people away from that offensive information is becoming one of the most important research areas in network information security. Some applications which can block or filter such information are used. Approaches in those systems can be roughly classified into two kinds:metadata based and content based. With the development of distributed technologies, content based filtering technologies will play a more and more important role in filtering systems. Keyword matching is a content based method used widely in harmful text filtering. Experiments to evaluate the recall and precision of the method showed that the precision of the method is not satisfactory, though the recall of the method is rather high. According to the results, a new pornographic text filtering model based on reconfirming is put forward. Experiments showed that the model is practical, has less loss of recall than the single keyword matching method, and has higher precision.  相似文献   
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