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Central to argument are evidence-based claims, requiring coordination of a claim with evidence bearing on it. We advocate a dialogic approach to developing argument skills and in the work reported here examine the further scaffold of prompts that exemplify functions of evidence in relation to a claim. This scaffold was successful in accelerating the prevalence of evidence-based claims in essays of low-performing middle schoolers compared to participants in the same year-long dialog-based intervention who received no or a limited form of evidence prompts and compared to previous samples engaged in a nondialogic curriculum. An experimental group achieved a proportion of evidence-based claims above 50% by the end of the year, transferring their newly developing skill from one topic to another. The use of different types of evidence emerged in a sequence corresponding to the cognitive demands they posed. Students first used support-own evidence. They used weaken-other evidence increasingly over time, but the two evidence types inconsistent with their position (support-other and weaken-own) showed lesser and later gains. Supporting a dialogic approach, qualitative data showed that evidence use occurred most readily in dialogs; then in individual writing on the same topic; and to a more limited extent in essays on a new, unstudied topic. 相似文献
74.
Technological agglomeration and the emergence of clusters and networks in nanotechnology 总被引:3,自引:0,他引:3
Research and development at the nanoscale requires a large degree of integration, from convergence of research disciplines in new fields of enquiry to new linkages between start-ups, regional actors and research facilities. Based on the analysis of two clusters in nanotechnologies (MESA+ (Twente) and other centres in The Netherlands and Minatec in Grenoble in France), the paper discusses the phenomenon of technological agglomeration: co-located scientific and technological fields associated to coordinated technology platforms to some extent actively shaped by institutional entrepreneurs. Such co-location and coordination are probably a pre-requisite for the emergence of strong nanoclusters. 相似文献
75.
Eann A. Patterson Patricia B. Campbell Ilene Busch-Vishniac Darrell W. Guillaume 《European Journal of Engineering Education》2011,36(3):211-224
The self-belief, motivation, tendency to procrastinate and learning styles of engineering students are discussed. It is proposed that engineering has developed an idiom and a learning approach that favours the dominant client, i.e. men, while simultaneously undermining the self-efficacy and motivation of women. Thematic coherence and teaching within a context that is familiar to students have been shown previously to be effective approaches for engaging students and are extended here to utilise the common experiences of all students to initiate the learning cycle. These approaches are combined with a template for teaching that uses the 5Es (Engage, Explore, Explain, Elaborate and Evaluate) in order to render the fundamentals of engineering more accessible to all students. This methodology can be introduced by individual instructors, who will be rewarded by students who are more engaged, more motivated and more likely to give a higher rating to the instructor and the course. 相似文献
76.
Bernard J. Jansen Zhe Liu Courtney Weaver Gerry Campbell Matthew Gregg 《Information processing & management》2011
Real time search is an increasingly important area of information seeking on the Web. In this research, we analyze 1,005,296 user interactions with a real time search engine over a 190 day period. Using query log analysis, we investigate searching behavior, categorize search topics, and measure the economic value of this real time search stream. We examine aggregate usage of the search engine, including number of users, queries, and terms. We then classify queries into subject categories using the Google Directory topical hierarchy. We next estimate the economic value of the real time search traffic using the Google AdWords keyword advertising platform. Results shows that 30% of the queries were unique (used only once in the entire dataset), which is low compared to traditional Web searching. Also, 60% of the search traffic comes from the search engine’s application program interface, indicating that real time search is heavily leveraged by other applications. There are many repeated queries over time via these application program interfaces, perhaps indicating both long term interest in a topic and the polling nature of real time queries. Concerning search topics, the most used terms dealt with technology, entertainment, and politics, reflecting both the temporal nature of the queries and, perhaps, an early adopter user-based. However, 36% of the queries indicate some geographical affinity, pointing to a location-based aspect to real time search. In terms of economic value, we calculate this real time search stream to be worth approximately US $33,000,000 (US $33 M) on the online advertising market at the time of the study. We discuss the implications for search engines and content providers as real time content increasingly enters the main stream as an information source. 相似文献
77.
Edwards TL Harper JC Polsky R Lopez DM Wheeler DR Allen AC Brozik SM 《Biomicrofluidics》2011,5(4):44115-4411514
Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices. 相似文献
78.
Miller PR Gittard SD Edwards TL Lopez DM Xiao X Wheeler DR Monteiro-Riviere NA Brozik SM Polsky R Narayan RJ 《Biomicrofluidics》2011,5(1):13415
In this study, carbon fiber electrodes were incorporated within a hollow microneedle array, which was fabricated using a digital micromirror device-based stereolithography instrument. Cell proliferation on the acrylate-based polymer used in microneedle fabrication was examined with human dermal fibroblasts and neonatal human epidermal keratinocytes. Studies involving full-thickness cadaveric porcine skin and trypan blue dye demonstrated that the hollow microneedles remained intact after puncturing the outermost layer of cadaveric porcine skin. The carbon fibers underwent chemical modification in order to enable detection of hydrogen peroxide and ascorbic acid; electrochemical measurements were demonstrated using integrated electrode-hollow microneedle devices. 相似文献
79.
Campbell Laurie O. Howard Cassandra Lambie Glenn W. Gao Xueying 《Education and Information Technologies》2022,27(6):8147-8163
Education and Information Technologies - Reading in upper-elementary grades includes comprehending complex texts and learning disciplinary-specific vocabulary. This study aims to determine the... 相似文献
80.
What Could Have Been Done? Circuit City: A Case Study of Management and Employee Performance Failure
Todd A. Campbell 《Performance Improvement》2014,53(4):16-23
This case study is an employee performance analysis that utilizes Gilbert's behavior engineering model (Gilbert, 2007 ) as a theoretical framework to examine the events that caused Circuit City to fail in 2008. Additionally, the case study views the events through a systemic lens. As management implemented changes, employee morale and performance faltered, which in turn affected customer perceptions and attitudes. Taken together, these actions resulted in a negative feedback loop that greatly contributed to the demise of the company. 相似文献