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721.
Su-Yan PAN 《Frontiers of Education in China》2011,6(1):106-138
This is a documentary study of education abroad policy in the People’s Republic of China (PRC) between 1978 and 2009. By examining
the dynamics underpinning the PRC state’s efforts to shape the flow of Chinese students and scholars from and into China,
this article reveals the major strategies that have enabled education abroad to become a source of brain gain. It argues that
China’s brain gain strategies feature three characteristics: a proactive diplomatic approach to international educational
relations; strategic dependence on foreign higher education resources and a decentralized economic mechanism to raise foreign-trained
human capital. The paper concludes by discussing the implications of Chinese experience for our understanding of the complex
and dynamic relations between the state, the market, universities and international relations as relating to cross-border
academic mobility, international educational relations, and national development in a globalizing world. 相似文献
722.
723.
Hao Wang Qingyuan Zhu Lufeng Ding Yan Shen Chao-Yu Yang Fang Xu Chang Shu Yujie Guo Zhiwei Xiong Qinghong Shan Fan Jia Peng Su Qian-Ru Yang Bing Li Yuxiao Cheng Xiaobin He Xi Chen Feng Wu Jiang-Ning Zhou Fuqiang Xu Hua Han Pak-Ming Lau Guo-Qiang Bi 《国家科学评论(英文版)》2019,6(5):982
The speed of high-resolution optical imaging has been a rate-limiting factor for meso-scale mapping of brain structures and functional circuits, which is of fundamental importance for neuroscience research. Here, we describe a new microscopy method of Volumetric Imaging with Synchronized on-the-fly-scan and Readout (VISoR) for high-throughput, high-quality brain mapping. Combining synchronized scanning beam illumination and oblique imaging over cleared tissue sections in smooth motion, the VISoR system effectively eliminates motion blur to obtain undistorted images. By continuously imaging moving samples without stopping, the system achieves high-speed 3D image acquisition of an entire mouse brain within 1.5 hours, at a resolution capable of visualizing synaptic spines. A pipeline is developed for sample preparation, imaging, 3D image reconstruction and quantification. Our approach is compatible with immunofluorescence methods, enabling flexible cell-type specific brain mapping and is readily scalable for large biological samples such as primate brains. Using this system, we examined behaviorally relevant whole-brain neuronal activation in 16 c-Fos-shEGFP mice under resting or forced swimming conditions. Our results indicate the involvement of multiple subcortical areas in stress response. Intriguingly, neuronal activation in these areas exhibits striking individual variability among different animals, suggesting the necessity of sufficient cohort size for such studies. 相似文献
724.
以大花蕙兰的茎尖为外植体,探讨了不同培养基对原球茎增殖、分化和小苗诱导及壮苗生根的影响.结果表明:1)大花蕙兰组织培养的原球茎诱导和增殖都可以用培养基1/2MS BA1.0mg/L NAA0.5mg/L;2)适合大花蕙兰组织培养原球茎芽苗诱导的培养基配方为1/2MS BAl.5mg/L NAA0.5mg/L;3)适合大花蕙兰壮苗生根的培养基配方为1/2MS NAA0,1mg/L GAl.0mg/L的组合. 相似文献
725.
我们的时代是信息时代 ,科技发展突飞猛进。在脑科学领域有了许多令人激动的发现 ,全世界的一些专家和学者对大脑功能的研究越来越感兴趣。但对大脑功能的研究很多方面依旧是个谜。教师对大脑功能具有更多的认识和了解有助于他们在实施素质教育中改进教学方法 ,这是具有深远意义的。 相似文献
726.
727.
Landon B. Lempke Robert C. Lynall Nicole L. Hoffman Hannes Devos Julianne D. Schmidt 《运动与健康科学(英文)》2021,10(2):145
Background: Concussed patients have impaired reaction time (RT) and cognition following injury that may linger and impair driving performance. Limited research has used direct methods to assess driving-RT post-concussion. Our study compared driving RT during simulated scenarios between concussed and control individuals and examined driving-RT''s relationship with traditional computerized neurocognitive testing (CNT) domains.MethodsWe employed a cross-sectional study among 14 concussed (15.9 ± 9.8 days post-concussion, mean ± SD) individuals and 14 healthy controls matched for age, sex, and driving experience. Participants completed a driving simulator and CNT (CNS Vital Signs) assessment within 48 h of symptom resolution. A driving-RT composite (ms) was derived from 3 simulated driving scenarios: stoplight (green to yellow), evasion (avoiding approaching vehicle), and pedestrian (person running in front of vehicle). The CNT domains included verbal and visual memory; CNT-RT (simple-, complex-, Stroop-RT individually); simple and complex attention; motor, psychomotor, and processing speed; executive function; and cognitive flexibility. Independent t tests and Hedge d effect sizes assessed driving-RT differences between groups, Pearson correlations (r) examined driving RT and CNT domain relationships among cohorts separately, and p values were controlled for false discovery rate via Benjamini-Hochberg procedures (α = 0.05).ResultsConcussed participants demonstrated slower driving-RT composite scores than controls (mean difference = 292.86 ms; 95% confidence interval (95%CI): 70.18–515.54; p = 0.023; d = 0.992). Evasion-RT (p = 0.054; d = 0.806), pedestrian-RT (p = 0.258; d = 0.312), and stoplight-RT (p = 0.292; d = 0.585) outcomes were not statistically significant after false-discovery rate corrections but demonstrated medium to large effect sizes for concussed deficits. Among concussed individuals, driving-RT outcomes did not significantly correlate with CNT domains (r-range: –0.51 to 0.55; p > 0.05). No correlations existed between driving-RT outcomes and CNT domains among control participants either (r-range: –0.52 to 0.72; p > 0.05).ConclusionSlowed driving-RT composite scores and large effect sizes among concussed individuals when asymptomatic signify lingering impairment and raise driving-safety concerns. Driving-RT and CNT-RT measures correlated moderately but not statistically, which indicates that CNT-RT is not an optimal surrogate for driving RT. 相似文献
728.
BackgroundMolecular brain therapies require the development of molecular switches to control gene expression in a limited and regulated manner in time and space. Light-switchable gene systems allow precise control of gene expression with an enhanced spatio-temporal resolution compared to chemical inducers. In this work, we adapted the existing light-switchable Light-On system into a lentiviral platform, which consists of two modules: (i) one for the expression of the blue light-switchable trans-activator GAVPO and (ii) a second module containing an inducible-UAS promoter (UAS) modulated by a light-activated GAVPO.ResultsIn the HEK293-T cell line transfected with this lentiviral plasmids system, the expression of the reporter mCherry increased between 4 to 5 fold after light induction. A time expression analysis after light induction during 24 h revealed that mRNA levels continuously increased up to 9 h, while protein levels increased throughout the experiment. Finally, transduction of cultured rat hippocampal neurons with this dual Light-On lentiviral system showed that CDNF, a potential therapeutic trophic factor, was induced only in cells exposed to blue light.ConclusionsIn conclusion, the optimized lentiviral platform of the Light-On system provides an efficient way to control gene expression in neurons, suggesting that this platform could potentially be used in biomedical and neuroscience research, and eventually in brain therapies for neurodegenerative diseases.How to cite: Zárate RV, Arancibia D, Fernández A, et al. Optimization of the Light-On system in a lentiviral platform to a light-controlled expression of genes in neurons. Electron J Biotechnol 2021;51. https://doi.org/10.1016/j.ejbt.2021.03.006 相似文献
729.
Catherine Bate Kim Turner Silke Fricke 《Journal of Research in Special Educational Needs》2021,21(3):242-253
Childhood acquired brain injury (ABI) is associated with poorer life outcomes. Increasing numbers of children and young people are surviving severe brain injury and returning to mainstream schools with multiple impairments. It is widely acknowledged that for these children, their school becomes by default their rehabilitation centre. International studies of this transition and a recent UK government report criticize educators' inconsistent implementation of support strategies, lack of educator training and poor communication between clinicians, educators, child and family. The educators' perspectives of the return-to-school are, however, not well represented in the literature. This study therefore explored the experiences of educators in the UK (N = 10) who had recently facilitated a return-to-school of a child with ABI aged 8–12 (N = 5) using semi-structured interviews analysed by data-driven thematic analysis. The findings highlight common experiences: a continuum of intensive problem-solving with heavy reliance on the Special Educational Needs Coordinator; educators valuing collaboration with clinical specialists in context over general ‘training’; uncertainty over the validity of implementing support strategies from prior teaching experience; uncertainty about how to support the child's emotional needs; and frustration with UK statutory processes for Special Educational Needs and Disabilities. Recommendations are made for changes to practice and future research. 相似文献
730.
活性碳在半夏组织培养中的使用 总被引:4,自引:0,他引:4
在半夏成熟叶片的初代培养中,使用0.25 ̄0.5%的活性碳对材料褐变有抑制作用;而加入活性碳对半夏试管苗的伸长有促进,但不同浓度差异不显著;0.05 ̄0.25%的活性碳能降低半夏玻化苗率,1%的活性碳则对苗的生长有抑制。 相似文献