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571.
We investigate the value creation or destruction associated with the introduction of software patents in the United States in two ways. The first looks at the cumulative abnormal returns to Information and Communication Technology (ICT) firms around the time of important court decisions that impacted software patents, and the second analyzes the relationship between firms’ stock market value, the sector in which they operate, and their holdings of software patents. We conclude that the market evaluated software patents as a negative development ex ante. Ex post, a greater number of firms in all ICT sectors invested in these patents, and these firms had slightly higher market values than those with no software patents. However, while we obtain clear evidence that the technological importance or quality of patented innovation mattered for the market value of hardware firms both before and after the legal changes, it is less clear that the marginal patent right per se was associated with increases in market value, and there are no significant valuation effects associated with patents for pure software firms after the change.  相似文献   
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Education policy has historically been viewed as having an influential part in crafting the roles of immigrants in American society. However, while policy makers continue to push their own agendas on English language learners (ELLs), ELLs continue to push back to create their own sense of what it means be an American. This article analyzes how formal and informal language policies have historically driven the instruction of ELLs and argues that despite attempts to enculturate and/or assimilate ELLs into American schools through strict English instruction, students employ a variety of cultural resources to act agentically in their acculturation.  相似文献   
575.
In Rabelais and His World Mikhail Bakhtin traces the history of laughter and the specific impact of Francois Rabelais upon that history, but more important it is the most definitive example of the carnivalesque available to Western scholars to date. By carnivalesque he refers to the traditional language and spectacle associated with folk culture within the carnival season, language and images that represent the universal truths of life, death, and renewal through the grotesque body. Bakhtin’s theories of the characteristics of unbridled freedom illustrate the universality and dissident effects of laughter. The revolutionary or subversive, carnival spirit displayed by the clash between official and unofficial culture bear particular significance upon the Harry Potter series. At the heart of carnival imagery is what Bakhtin defines as the three elements of laughter: “universalism, freedom, and… [their] relation to the people’s unofficial truth” (p. 90). These are the elements of laughter that most adequately characterize Harry Potter’s subjective view of what is good and right. He is at the most basic level an initiate of change who works within the realm of the carnivalesque to illustrate the subversive qualities of laughter in opposition to the official culture the muggle world represents with regards to race. The carnivalesque and grotesque in Harry Potter illustrates an appeal to social transformation through the power of laughter and the reversal of the dominant order of race and racial difference.  相似文献   
576.
The determination of the ventilatory threshold has been a persistent problem in research and clinical practice. Several computerized methods have been developed to overcome the subjectivity of visual methods but it remains unclear whether different computerized methods yield similar results. The purpose of this study was to compare nine regression-based computerized methods for the determination of the ventilatory threshold. Two samples of young and healthy volunteers (n = 30 each) participated in incremental treadmill protocols to volitional fatigue. The ventilatory data were averaged in 20-s segments and analysed with a computer program. Significant variance among methods was found in both samples (Sample 1: F = 11.50; Sample 2: F = 11.70, P < 0.001 for both). The estimates of the ventilatory threshold ranged from 2.47 litres.min(-1) (71% VO2max) to 3.13 litres.min(-1) (90% VO2max) in Sample 1 and from 2.37 litres.min(-1) (67% VO2max) to 3.03 litres.min(-1) (83% VO2max) in Sample 2. The substantial differences between methods challenge the practice of relying on any single computerized method. A standardized protocol, likely based on a combination of methods, might be necessary to increase the methodological consistency in both research and clinical practice.  相似文献   
577.
Language teacher education by distance (LTED) has become a widespread and important practice in the preservice and in‐service education of teachers, and in language education internationally. The advent of the Internet has combined with developments in other information communication technologies, the globalisation of English, and the marketisation of education to afford a rapid increase in the number of TESOL (Teaching English to Speakers of other Languages) teacher education programs, and greater variety in the ways in which teaching and learning is mediated in these programs. This article reports on an international survey of TESOL teacher education providers, and considers the status of language teaching qualifications earned by distance, changes in the institutional roles of language teacher educators, and the current state of research into LTED.  相似文献   
578.
This paper turns the kaleidoscopic lens of Professor Deborah Britzman’s writings on a student teacher story of learning to teach. It begins by briefly setting the context for the research. It then explains the study’s ontological and epistemological focus on experience and how student teacher and researchers create expressions of experience through an interpretative process. This leads to the design for interpretation in this study and to an explanation of why the work of Britzman became part of the interpretative layering for understanding student teacher Ciara’s texts. It continues by explicating Britzman’s concept of ‘struggle for voice’ as a metaphor for learning to teach and briefly makes comparison with the work of Bakhtin and his concept of the dialogical imagination. It then presents the layered interpretation in the form of indicative excerpts in a chronological story. Finally it focuses on the salient and pervading theme of affect and offers a brief commentary on its significance in initial teacher education and the need for developing an understanding for the feeling world of learning to teach.  相似文献   
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In three experiments, we set out to determine whether the response of rats to an injection of LiCl would be modified by the presence of an environmental context that had previously been paired with LiCl. Experiment 1 confirmed that one feature of the malaise produced by LiCl is a reduced tendency to consume an otherwise palatable flavor. Experiment 2 showed that the size of this response was enhanced if it was measured in the presence of a conditioned context. In Experiment 3, we investigated the possibility that the postinjection response could be modified by an overshadowing treatment given during the conditioning phase. The significance of these findings for the understanding of chemotherapyinduced nausea in the clinical population is discussed.  相似文献   
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