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911.
The aim of this article is to elucidate how a new system of school and teacher assessment in Catalonia is transforming the conceptions, practices and identity of head teachers, especially younger ones. It begins by considering the impact of global neoliberal policies on educational practices, highlighting their Foucauldian productive nature. It then examines the educational context of Catalonia during the last 30 years, emphasising the changing role of head teachers and the impact of neoliberal governance. This is followed by an account and analysis of in-depth interviews with four head teachers, focusing especially on how the head teacher’s objectives, practices and identities are being transformed, or produced, as a result of the new neoliberal ‘assessment regime’. It ends with a discussion on the importance of refusal and resistance to this process and the need to reconsider basic educational and social questions.  相似文献   
912.
    

Introduction

Nowadays, on-a-chip capillary electrophoresis is a routine method for the detection of PCR fragments. The Agilent 2100 Bioanalyzer was one of the first commercial devices in this field. Our project was designed to study the characteristics of Agilent DNA 1000 kit in PCR fragment analysis as a part of circulating tumour cell (CTC) detection technique. Despite the common use of this kit a complex analysis of the results from a long-term project is still missing.

Materials and methods

A commercially available Agilent DNA 1000 kit was used as a final step in the CTC detection (AdnaTest) for the determination of the presence of PCR fragments generated by Multiplex PCR. Data from 30 prostate cancer patients obtained during two years of research were analyzed to determine the trueness and precision of the PCR fragment size determination. Additional experiments were performed to demonstrate the precision (repeatability, reproducibility) and robustness of PCR fragment concentration determination.

Results

The trueness and precision of the size determination was below 3% and 2% respectively. The repeatability of the concentration determination was below 15%. The difference in concentration determination increases when Multiplex-PCR/storage step is added between the two measurements of one sample.

Conclusions

The characteristics established in our study are in concordance with the manufacturer’s specifications established for a ladder as a sample. However, the concentration determination may vary depending on chip preparation, sample storage and concentration. The 15% variation of concentration determination repeatability was shown to be partly proportional and can be suppressed by proper normalization.Key words: lab-on-a-chip devices, capillary electrophoresis, multiplex PCR, circulating tumour cells, Agilent DNA 1000 kit  相似文献   
913.
ABSTRACT

Our understanding of spelling development has largely been gleaned from analysis of children’s accuracy at spelling words under varying conditions and the nature of their errors. Here, we consider whether handwriting durations can inform us about the time course with which children use morphological information to produce accurate spellings of root morphemes. Six- to 7-year-old (n = 23) and 8- to 11-year-old (n = 25) children produced 28 target spellings in a spelling-to-dictation task. Target words were matched quadruplets of base, control, inflected, and derived words beginning with the same letters (e.g., rock, rocket, rocking, rocky). Both groups of children showed evidence of morphological processing as they prepared their spelling; writing onset latencies were shorter for two-morpheme words than control words. The findings are consistent with statistical learning theories of spelling development and theories of lexical quality that include a role of morphology.  相似文献   
914.
Previous studies have found that reduced stick stiffness increases puck velocity in young male ice hockey players. This study investigates the hypothesis that female players are disadvantaged by using equipment that is designed for taller and stronger players. The purpose of this study was to investigate if stick flexibility and puck weight affect puck velocity in standing slap shots performed by female ice hockey players. There was a significant increase in puck velocity (4.1%, p = 0.037) when stick stiffness and puck weight were reduced. ANOVA revealed that there was a significant correlation between stick, puck and the participant herself (R 2 = 0.987). Spearman’s correlation analysis revealed that participants with higher puck velocities benefitted the most when the stick flexibility and puck weight were reduced (r = 0.648, p = 0.043). It was concluded that decreased stick stiffness and puck weight increased puck velocity in standing slap shots for female ice hockey players.  相似文献   
915.
    
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916.
Studies on proficient readers showed that speech processing is affected by knowledge of the orthographic code. Yet, the automaticity of the orthographic influence depends on task demand. Here, we addressed this automaticity issue in normal and dyslexic adult readers by comparing the orthographic effects obtained in two speech processing tasks that are or not sensitive to strategies developed by participants. Our finding showed that while participants’ performance in a metaphonological task, which is known to be strategy prone, was affected by their orthographic knowledge regardless of the childhood diagnosis of dyslexia or of their actual reading-related skills, this latter factor significantly modulated the orthographic influence found in a more natural speech recognition task. The finding supports the claim that while any individuals who know a reading code are able to resort to their orthographic knowledge when they process speech, a more profound modification of the speech processing system by the orthographic code takes place only in readers who have reached a certain level of reading expertise.  相似文献   
917.
The use of human material in anatomy education depends upon the generosity of body donors. However, little is known regarding the demographics of body donors in Brazil, where voluntary body donation is a relatively rare phenomenon. Hence, the aim of the present study was to elucidate the demographic profile of applicants to the Body Donation Program (BDP) at the Federal University of Health Sciences of Porto Alegre in Brazil, as well as to assess whether the observed characteristics of body donors are unique to that sample, or if they merely reflect the characteristics of the regional population. Information derived from the specific forms filled out by donors between January 2008 and June 2016 at the time of registration were collected. Data from 416 forms were analyzed. Based on this study, the typical applicant in Brazil is typically a white female (67.4%), over 60 years of age (60.3%), unmarried or single (70.6%), affiliated with a religious group (89.1%), of middle class background (40.4%), who has completed high school and/or holds a university degree (93.8%). The motivation of donors was, in most cases, an altruistic gesture, represented by the desire to help society and science. Elucidating these demographic characteristics of potential donors may help identify the target public to which information regarding body donation campaigns could be directed. Anat Sci Educ 10: 475–486. © 2017 American Association of Anatomists.  相似文献   
918.
    
As expectations of the economic impact of educational attainment are soaring (Hanushek & Woessmann, 2009 Hanushek E. A., & Woessmann, L. (2009). Do better schools lead to more growth? Cognitive skills, economic outcomes, and causation (NBER Working Paper, No. 14633). Cambridge, MA: National Bureau of Economic Research.[Crossref] [Google Scholar]) and conjectures about successful national educational reforms (Mourshed, Chijioke, & Barber, 2010 Mourshed, M., Chijioke, C., & Barber, M. (2010). How the world's most improved school systems keep getting better. Retrieved from http://www.mckinsey.com/client_service/social_sector/latest_thinking/worlds_most_improved_schools[Crossref] [Google Scholar]) are welcomed by educational policy-makers in many countries, a careful assessment of the empirical evidence for these kinds of claims is needed. In this article, we present a methodology that was applied to an international data set. A multi-level model of education was used to present a hypothetical scenario, indicated as the “implementation scenario”. The scenario was tested on the Programme for International Student Assessment (PISA) 2009 data set by means of multi-level structural equation modelling. Although we find some evidence for direct effects and some support for straightforward implementation, the overall impact of malleable conditions at the system and school level appears disappointingly small. A theoretical strand of literature that would account for “limited malleability” is referred to in discussing these results.  相似文献   
919.
    
This study examined how the link between neighborhood poverty and the timing of sexual initiation varies as a function of age, gender, and background characteristics. A sample of N = 2,596 predominately White Canadian adolescents from the National Longitudinal Survey of Children and Youth was used. Sexual initiations occurring between 12 and 15 years old were considered. Results showed that younger adolescent females who lived in poor neighborhoods and who had a history of conduct problems were more likely to report early sexual activity. Peer characteristics partly accounted for this susceptibility. Among adolescent males, no direct neighborhood effects were found, but those who had combined risks at multiple levels appeared more vulnerable. The theoretical and practical implications of these findings are discussed.  相似文献   
920.
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