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Alexandra LaLonde Maria F. Romero-Creel Mario A. Saucedo-Espinosa Blanca H. Lapizco-Encinas 《Biomicrofluidics》2015,9(6)
Isolation and enrichment of low-abundant particles are essential steps in many bio-analytical and clinical applications. In this work, the capability of an insulator-based dielectrophoresis (iDEP) device for the detection and stable capture of low abundant polystyrene particles and yeast cells was evaluated. Binary and tertiary mixtures of particles and cells were tested, where the low-abundant particles had concentration ratios on the order of 1:10 000 000 compared to the other particles present in the mixture. The results demonstrated successful and stable capture and enrichment of rare particles and cells (trapping efficiencies over 99%), where particles remained trapped in a stable manner for up to 4 min. A device with four reservoirs was employed for the separation and enrichment of rare particles, where the particles of interest were first selectively concentrated and then effectively directed to a side port for future collection and analysis. The present study demonstrates that simple iDEP devices have appropriate screening capacity and can be used for handling samples containing rare particles; achieving both enrichment and isolation of low-abundant particles and cells. 相似文献
83.
Irene R. Faber Maria W. G. Nijhuis-Van Der Sanden Marije T. Elferink-Gemser Frits G. J. Oosterveld 《Journal of sports sciences》2015,33(11):1149-1158
A motor skills assessment could be helpful in talent development by estimating essential perceptuo-motor skills of young players, which are considered requisite to develop excellent technical and tactical qualities. The Netherlands Table Tennis Association uses a motor skills assessment in their talent development programme consisting of eight items measuring perceptuo-motor skills specific to table tennis under varying conditions. This study aimed to investigate this assessment regarding its reproducibility, internal consistency, underlying dimensions and concurrent validity in 113 young table tennis players (6–10 years). Intraclass correlation coefficients of six test items met the criteria of 0.7 with coefficients of variation between 3% and 8%. Cronbach’s alpha valued 0.853 for internal consistency. The principal components analysis distinguished two conceptually meaningful factors: “ball control” and “gross motor function.” Concurrent validity analyses demonstrated moderate associations between the motor skills assessment’s results and national ranking; boys r = ?0.53 (P < 0.001) and girls r = ?0.45 (P = 0.015). In conclusion, this evaluation demonstrated six test items with acceptable reproducibility, good internal consistency and good prospects for validity. Two test items need revision to upgrade reproducibility. Since the motor skills assessment seems to be a reproducible, objective part of a talent development programme, more longitudinal studies are required to investigate its predictive validity. 相似文献
84.
Maria C. Porcal-Gonzalo 《Journal of Map & Geography Libraries》2015,11(3):289-329
In recent years, there has been a growing recognition of the fact that the proper management of information has to include concern for its preservation and future re-use. This ambition is particularly significant for geospatial data. The primary aim of this article is to define the European and Spanish frameworks for the preservation and reutilization of geographical information, with the ultimate goal of proposing an articulated, lifecycle-based data management model. With this, the intent is to shed some light on a complex, difficult and ever-evolving subject.The article is divided into two main parts. The first part begins with a conceptual justification for geospatial data management and continues by synthesizing the current normative and technological framework for the preservation and reutilization of geographical information. Within this context, the implementation of Spatial Data Infrastructures (SDI) in Spain is evaluated. The second part begins with a case study from Spain that aims to identify different agents and flows that influence the lifecycle of geographical data, as well as the strengths and weaknesses found in each stage of the process under examination. Finally, the foregoing ideas are used in order to propose a SDI-related system for the management of geographical information. 相似文献
85.
文章首先介绍了巴西档案学课程在大学设立的历程,接着讨论了巴西档案学与情报学的关系,论述了知识信息时代巴西档案工作者培养计划面临的挑战和应对措施,最后,针对巴西档案学及巴西档案工作人才培养面临的挑战得出了几点结论. 相似文献
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This study investigated development of the Big Five personality traits from early childhood into adulthood. An initial group of 137 Swedish children were assessed eight times between ages 2 and 29 years. Initial decreases in extraversion leveled off in early adulthood; agreeableness and conscientiousness increased from ages 2 to 29; neuroticism initially increased, leveled off in later childhood and adolescence, and decreased throughout early adulthood; while openness to experience showed an initial increase, then decreased and leveled off in early adulthood. Individual developmental trajectories varied significantly, particularly in relation to gender. Personality traits became increasingly stable, and the fact that childhood scores predicted scores in adulthood indicated that personalities are fairly stable across this portion of the life span. 相似文献
88.
Reading difficulties and attention‐deficit/hyperactivity behaviours: evidence of an early association in a nonclinical sample 下载免费PDF全文
Chiara Luoni Umberto Balottin Maria Zaccagnino Laura Brembilla Giulia Livetti Cristiano Termine 《Journal of Research in Reading》2015,38(1):73-90
Attention‐deficit/hyperactivity disorder (ADHD) often co‐occurs with reading disability. A cross‐sectional study in an Italian‐speaking, nonclinical sample was conducted in an attempt to document the existence of an early association between reading difficulties (RD) and ADHD behaviours. We recruited a sample of 369 children in their first year at primary school. Of the sample, 8.4% displayed RD; 7.0% had ADHD; 3.5% presented both RD and ADHD behaviours; 50% of the children with ADHD displayed RD; 41.9% of those with RD displayed ADHD behaviours. Low socioeconomic status was associated with a fourfold increased probability of displaying RD (odds ratio = 3.98), but not ADHD behaviours. In this nonclinical sample, we detected an early association between ADHD behaviours and RD. A key role in this association may be played by inattention symptoms, which occurred with significantly increased frequency also in the group presenting only RD. 相似文献
89.
Children need a balanced set of cognitive, social and emotional capabilities to adapt to today's demanding, changing and unpredictable world. OECD countries and partner economies recognise the importance on the holistic development of individuals. However, there are big gaps between stakeholders' knowledge, expectations and practices on how to foster such skills. This paper presents evidence on the importance of social and emotional skills; on how policy makers and schools are currently enhancing and monitoring such skills; and, on the existing gaps between knowledge, expectations and practices to mobilise these skills. The paper concludes by pointing ways in which education stakeholders can do more to better develop and mobilise the skills that drive individual's well-being and social progress. The paper draws on findings and frameworks that are being published in a full OECD report entitled ‘Skills for Social Progress: the Power of Social and Emotional Skills’ in the first half of 2015. 相似文献
90.