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961.
Thomas Eckes 《教育实用测度》2015,28(2):85-98
C-tests are gap-filling tests widely used to assess general language proficiency for purposes of placement, screening, or provision of feedback to language learners. C-tests consist of several short texts in which parts of words are missing. We addressed the issue of local dependence in C-tests using an explicit modeling approach based on testlet response theory. Data were provided by a total sample of 4,708 participants working on eight C-test texts with 20 gaps each. The resulting parameter estimates were compared to those obtained from (a) a polytomous item response theory (IRT) model and (b) a standard IRT model that ignored the dependence structure. Testlet effects proved to be very small and correspondence between parameters obtained from the different modeling approaches was high. When local dependence was ignored reliability of the C-test was slightly overestimated. Implications for the analysis of testlets in general, and C-tests in particular are discussed. 相似文献
962.
David Vittle Thomas 《Educational studies》2015,41(1-2):188-208
This study explores the perspectives of education practitioners towards the process of reintegrating pupils (many of whom display social, emotional and behavioural difficulties), from a pupil referral unit (PRU) to mainstream educational provision in a rural bilingual Welsh authority, and examines the barriers and facilitators they identified as evident within their individual schools and catchment area served with regards to reintegrating and including pupils. The study locates the process within a specific geographical context and discusses whether there are specific reintegration barriers and facilitators inherent within the setting. Patterns of pupil referral and reintegration between the PRU and mainstream schools were examined and analysed from “pupil tracking data” which tracked pupils throughout an academic year from their arrival at the PRU before the perspectives of education practitioners towards potential reintegration barriers and facilitators were gathered through an initial expert sample and a second landscape sample postal questionnaire. Interviews were subsequently conducted with respondents from Primary, Secondary and PRU settings to drill down into the influence of specific barriers and facilitators identified earlier. This study suggests that although generic reintegration barriers and facilitators may be evident within all settings, there were specific factors inherent within this geographical context identified by education practitioners, which acted in the most part as barriers to successful reintegration and inclusion. 相似文献
963.
Lisa Sprenger Silvio Dutz Thomas Schneider Stefan Odenbach Urs O. H?feli 《Biomicrofluidics》2015,9(4)
Microfluidic spirals were used to successfully separate rare solid components from unpretreated human whole blood samples. The measured separation ratio of the spirals is the factor by which the concentration of the rare component is increased due to the Dean effect present in a flow profile in a curved duct. Different rates of dilution of the blood samples with a phosphate-buffered solution were investigated. The diameters of the spherical particles to separate ranged from 2 μm to 18 μm. It was found that diluting the blood to 20% is optimal leading to a separation ratio up to 1.97. Using two spirals continuously placed in a row led to an increase in separation efficacy in samples consisting of phosphate-buffered solution only from 1.86 to 3.79. Numerical investigations were carried out to display the flow profiles of Newtonian water samples and the shear-thinning blood samples in the cross-section of the experimentally handled channels. A macroscopic difference in velocity between the two rheologically different fluids could not be found. The macroscopic Dean flow is equally present and useful to help particles migrate to certain equilibrium positions in blood as well as lower viscous Newtonian fluids. The investigations highlight the potential for using highly concentrated, very heterogeneous, and non-Newtonian fluidic systems in known microsystems for screening applications. 相似文献
964.
Sculptures of athletes that immortalize heroic feats have long been part of the sporting world. More recently, statues of sports fans have appeared, particularly at baseball stadiums across North America. Whilst athlete statues usually represent specific subjects, fan statues typically depict anonymous figures, giving commissioners and sculptors broader license to incorporate particular ideals. This paper investigates how the fan statuary's form reflects commissioners' motivations, values, and views of fandom, and whether fan statues promote a preferred (but often imaginary) narrative regarding the fan experience. A tripartite fan statue design typology is proposed: hero worship, family experiences, and the crowd. By examining an example of each type, with context provided by a unique database of baseball statuary, the fan statuary's predominant themes and tensions are illustrated. Fan statues are concentrated at Minor League ballparks, and all feature children. The majority are alloys of both real and imagined components of the idealized fan experience of the baseball organization's ‘ideal fan’, projecting inclusive, family-friendly, and timeless game day experiences, and evoking nostalgia for childhood. Crowd-type statues offer a more free-spirited and spontaneous aesthetic, with the crowd creating and becoming part of the spectacle – a reality that sports organizations may be less comfortable with. 相似文献
965.
Objective:There are no existing validated search filters for the group of 37 Organisation for Economic Co-operation and Development (OECD) countries. This study describes how information specialists from the United Kingdom''s National Institute for Health and Care Excellence (NICE) developed and evaluated novel OECD countries’ geographic search filters for MEDLINE and Embase (Ovid) to improve literature search effectiveness for evidence about OECD countries.Methods:We created the draft filters using an alternative approach to standard filter construction. They are composed entirely of geographic subject headings and are designed to retain OECD country evidence by excluding non-OECD country evidence using the NOT Boolean operator. To evaluate the draft filters’ effectiveness, we used MEDLINE and Embase literature searches for three NICE guidelines that retrieved >5,000 search results. A 10% sample of the excluded references was screened to check that OECD country evidence was not inadvertently excluded.Results:The draft MEDLINE filter reduced results for each NICE guideline by 9.5% to 12.9%. In Embase, search results were reduced by 10.7% to 14%. Of the sample references, 7 of 910 (0.8%) were excluded inadvertently. These references were from a guideline about looked-after minors that concerns both OECD and non-OECD countries.Conclusion:The draft filters look promising—they reduced search result volumes while retaining most OECD country evidence from MEDLINE and Embase. However, we advise caution when using them in topics about both non-OECD and OECD countries. We have created final versions of the search filters and will validate them in a future study. 相似文献
966.
967.
Thomas D. Wolkow Lisa T. Durrenberger Michael A. Maynard Kylie K. Harrall Lisa M. Hines 《CBE life sciences education》2014,13(4):724-737
Early research experiences must be made available to all undergraduate students, including those at 2-yr institutions who account for nearly half of America''s college students. We report on barriers unique to 2-yr institutions that preclude the success of an early course-based undergraduate research experience (CURE). Using a randomized study design, we evaluated a CURE in equivalent introductory biology courses at a 4-yr institution and a 2-yr institution within the same geographic region. We found that these student populations developed dramatically different impressions of the experience. Students at the 4-yr institution enjoyed the CURE significantly more than the traditional labs. However, students at the 2-yr institution enjoyed the traditional labs significantly more, even though the CURE successfully produced targeted learning gains. On the basis of course evaluations, we enhanced instructor, student, and support staff training and reevaluated this CURE at a different campus of the same 2-yr institution. This time, the students reported that they enjoyed the research experience significantly more than the traditional labs. We conclude that early research experiences can succeed at 2-yr institutions, provided that a comprehensive implementation strategy targeting instructor, student, and support staff training is in place. 相似文献
968.
Andrew G. Campbell Rachel Skvirsky Henry Wortis Sheila Thomas Ichiro Kawachi Christine Hohmann 《CBE life sciences education》2014,13(4):587-592
This paper summarizes the outcomes of a retreat designed to cultivate interactions between trainees at various training levels and provide them opportunities to share their training perspectives and expectations. Retreat outcomes are used to support the development of better science, technology, engineering, and mathematics training practices by informing the trainers’ perspective. 相似文献
969.
Carrie J. Boyce Chandrani Mishra Kristy L. Halverson Aimée K. Thomas 《Journal of Science Education and Technology》2014,23(6):815-826
Informal environments provide students with unique experiences that allow them to actively participate in activities while promoting a positive attitude toward and an increased interest in science. One way to enhance informal science experiences is through the integration of mobile technologies. This integration is particularly useful in engaging underrepresented students in learning science. Our informal environmental science program engages underrepresented, fifth-grade students in an informal learning environment supplemented with mobile tablet technology (iPads). The purpose of this study was to explore how fifth-grade students interacted with nature using mobile technology during a nature hike series. Participants included 55 fifth-grade students from two low-income schools. We found that students used the mobile technology to explore nature and stay engaged throughout the hike. The iPads were used as references, data collectors, and engagement tools. Students had an intense desire in returning to the site and responded positively toward interacting with nature. Prior research has indicated that students in this age group are likely to lose interest in science and the incorporation of field-friendly technology that engages students with nature, not technology alone, is a useful tool for keeping students interested in science. 相似文献
970.