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81.
High-throughput study of alpha-synuclein expression in yeast using microfluidics for control of local cellular microenvironment 总被引:1,自引:0,他引:1
Microfluidics is an emerging technology which allows the miniaturization, integration, and automation of fluid handling processes. Microfluidic systems offer low sample consumption, significantly reduced processing time, and the prospect of massive parallelization. A microfluidic platform was developed for the control of the soluble cellular microenvironment of Saccharomyces cerevisiae cells, which enabled high-throughput monitoring of the controlled expression of alpha-synuclein (aSyn), a protein involved in Parkinson's disease. Y-shaped structures were fabricated using particle desorption mass spectrometry-based soft-lithography techniques to generate biomolecular gradients along a microchannel. Cell traps integrated along the microchannel allowed the positioning and monitoring of cells in precise locations, where different, well-controlled chemical environments were established. S. cerevisiae cells genetically engineered to encode the fusion protein aSyn-GFP (green fluorescent protein) under the control of GAL1, a galactose inducible promoter, were loaded in the microfluidic structure. A galactose concentration gradient was established in the channel and a time-dependent aSyn-GFP expression was obtained as a function of the positioning of cells along the galactose gradient. Our results demonstrate the applicability of this microfluidic platform to the spatiotemporal control of cellular microenvironment and open a range of possibilities for the study of cellular processes based on single-cell analysis. 相似文献
82.
A randomized, controlled study was conducted to assess the effects of the Nuestros Niños professional development program on classroom practices and child outcomes related to language development and early literacy skills in both English and Spanish. Fifty-five teachers and 193 Latino dual language learners (DLLs) enrolled in the North Carolina More at Four Pre-Kindergarten Program participated in the study. The content of the professional development program consisted of research-based instructional practices designed to complement the core curriculum and scaffold learning for DLLs, and the format included professional development institutes, individualized consultation, and community of practice meetings. The results showed that the intervention led to measurable improvements in both the overall quality of teachers’ language and literacy practices as well as those specific to working with Latino DLLs, and greater gains in children's phonological awareness skills in their primary language. 相似文献
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Virginia A. Aparicio Pilar Ruiz-Cabello Milkana Borges-Cosic Ana Andrade Irene Coll-Risco Pedro Acosta-Manzano 《Journal of sports sciences》2017,35(9):880-887
This study aimed to analyse the association of different components of physical fitness, body composition, cardiometabolic markers and the Mediterranean diet with bone mineral density (BMD) in perimenopausal women, and to test which of these components are independently associated with BMD. The sample comprised 197 perimenopausal women (52.6 ± 4.5 years). Physical fitness was assessed with the “Senior Fitness Test” battery and the handgrip strength and Bruce tests. Fat and lean mass and BMD were measured using dual-energy X-ray absorptiometry. We analysed the markers of metabolic syndrome, C-reactive protein, and components of the Mediterranean diet. Handgrip muscle strength (β = 0.212, P = 0.005), body weight (β = 0.244, P = 0.001), BMI (β = 0.180, P = 0.011) and lean mass (β = 0.379, P < 0.001) were positively associated with BMD. No associations were observed between cardiometabolic markers or the Mediterranean diet with BMD (all P > 0.05). When all relevant indicators of BMD were simultaneously considered, lean mass was the only 1 showing an independent association with BMD (β = 0.392, P < 0.001), explaining 14% of the BMD variability. In conclusion, muscle strength might be a marker of BMD in perimenopausal women. However, lean mass was the only factor independently associated with BMD. Future research to determine whether increasing lean mass through specific exercise-based interventions contributes to increasing BMD is warranted. 相似文献
85.
Elaine Virginia Howes 《科学教学研究杂志》1998,35(8):877-896
In this article, I explore how a dozen high-school sophomore girls expressed their relationship to and understanding of prenatal testing, and its possible place in their lives and in the lives of others, in the context of a short unit on prenatal testing during a semester-long course in human genetics. The data come from an assignment designed to help students bring their understanding of prenatal testing into the realm of personal choice, as well as practice applying the science of chromosomal inheritance. Difference feminism is used to develop themes evident in these girls' talk about prenatal testing. The instructional choices made were based on difference feminism, which implies that girls would be interested in science that connects to human bodies, children, and traditional women's responsibilities. This claim is elaborated on and applied by this study, in which I concentrate on the question: How can difference feminism help us better to hear and comprehend high school girls' relationships with reproductive technology, their own bodies, and their own lives? I propose that focusing on girls' lives and knowledge is a way to consider alternatives in curricular content, in addition to helping us learn how to help more girls connect with science. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 877–896, 1998. 相似文献
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A place-to-place migration study of first-time freshmen in American four-year colleges and universities presents student migration patterns for each of the fifty states and the District of Columbia in Fall 1986. Migration patterns of all first-time students are reviewed, but the focus of the study is first-time freshmen, the most critical population for institutional enrollment management. State-to-state matrix tables are presented that show where students come from and where they go to school for all fifty-one locations by sector of control (i.e., public and private).Presented at the 29th Annual Forum of the Association for Institutional Research, Baltimore, Maryland, May 2, 1989. 相似文献
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