几个重要生物实验的改进

本文通过实践摸索,发现几个重要生物实验中存在的弊端,并探索出一些行之有效,简单易行的改进方法,给同行提供参考。     

非正式网络对研发团队创造力的影响研究——以共享心智模型为中介变量

国内外学者迄今很少研究非正式网络与团队创造力的关系,对于团队外部非正式网络也没有给予足够的关注。以共享心智模型为中介变量,基于181个研发团队的数据,构建并验证了研发团队(内部和外部)非正式网络与团队创造力的关系。研究表明:团队内部、外部非正式网络与团队创造力均呈倒U函数关系;团队内部非正式网络与两类共享心智模型(任务式和协作式)均显著正相关,团队外部非正式网络与协作式共享心智模型显著正相关;团队内部非正式网络通过两类共享心智模型的中介作用影响团队创造力,团队外部非正式网络通过协作式共享心智模型的中介作用影响团队创造力。     

Governing software: networks,databases and algorithmic power in the digital governance of public education

This article examines the emergence of ‘digital governance’ in public education in England. Drawing on and combining concepts from software studies, policy and political studies, it identifies some specific approaches to digital governance facilitated by network-based communications and database-driven information processing software that are being discursively promoted in education by cross-sectoral intermediary organizations. Such intermediaries, including National Endowment for Science, Technology and the Arts, Demos, the Innovation Unit, the Education Foundation and the Nominet Trust, are increasingly seeking to participate in new digitally mediated forms of educational governance. Through their promotion of network-based pedagogies and database-driven analytics software, these organizations are seeking to delegate educational decision-making to socio-algorithmic forms of power that have the capacity to predict, govern and activate learners' capacities and subjectivities.     

How can science connect with and contribute to conservation? Recommendations and reflections

This paper reports the conclusions and recommendations of the working group that synthesized the discussions on ‘How can science connect with and be of greater benefit to conservation practice?’ during the ICCROM Forum on Conservation Science. The author reflects on these findings from her own perspective and experiences, and places them in the context of two major shifts in heritage research: the first, a shift in focus from conserving materials to managing meaning. The second, a shift in organizational structures from single, centrally funded heritage institutions towards diffuse networks which include new players who have no direct responsibility towards heritage. Both shifts are taking place in an environment of decreased funding and increased accountability to society. Science and conservation connect and contribute to each other most effectively if they together contribute to the societal benefits of heritage. In this regard, heritage science strategies can stimulate collaboration, and direct science and conservation towards innovative, applicable outcomes. Moreover, they can promote a transdisciplinary approach which connects social, economic and business sciences and stakeholders. They should also ensure the creation of sustainable nodes for consolidating knowledge within these dynamic networks.     

内质网应激介导细胞凋亡在运动预防非酒精性脂肪肝形成中的作用

摘要：目的：探讨运动对非酒精性脂肪肝（NAFLD）的预防作用及作用机理。方法： SD雄性大鼠随机分为对照组、模型组和运动组3 组。对照组给予普通饲料喂养,模型组予高脂饲料喂养,运动组在高脂饲料喂养的同时予运动干预,连续8周,直至实验结束。HE染色观察肝脏病理形态变化,TUNEL法测肝细胞凋亡,western blot检测CHOP、Caspase12和JNK蛋白表达,免疫组化检测CHOP、Caspase12和JNK蛋白阳性表达。结果：1）与对照组比较,模型组肝细胞脂肪性变明显,肝细胞凋亡指数升高,CHOP、Caspase12、JNK蛋白表达及阳性表达增加;2）与模型组比较,运动组肝细胞脂肪变性减轻,肝细胞凋亡指数减少,CHOP、Caspase12、JNK蛋白表达及阳性表达降低。结论：8周高脂饮食可成功复制NAFLD动物模型,内质网应激介导细胞凋亡参与NAFLD形成。运动对NAFLD形成具有较好的预防作用,其机制可能与运动可降低内质网应激介导细胞凋亡蛋白CHOP、JNK和Caspase12在肝细胞的表达,抑制肝细胞凋亡有关。     

机会网络中节点协作的Epidemic路由算法

Epidemic路由算法是一种多副本路由算法,在资源受限的情况下,会由于无限制的洪泛使得网络中存有大量的消息副本,消耗大量网络资源,导致网络性能下降。针对Epidemic路由算法中存在的问题,提出一种基于节点协作的Epidemic路由算法,该算法通过节点间相互的协作和一定策略抑制网络中副本数多的消息的转发机会,提高副本数少的消息的转发机会,进而控制网络中总的消息副本的增长,以此保证消息转发公平性和较好的网络性能。仿真结果表明,与传统的Epidemic路由算法和Prophet路由算法相比,该路由算法能显著提高消息的交付率,减少消息传输延迟和路由开销,有效提高了网络总体性能。     

基于Simulink的燃料电池汽车混合动力电驱动系统仿真

首先分析了燃料电池汽车混合动力电驱动系统基本结构并给出了等效电路,建立了电驱动系统的动态数学模型,主要包括:燃料电池系统、动力蓄电池、电动机和DC/DC转换器四个模块。采用最小二乘法对模型的参数进行了估计,典型工况下的估计结果显示模型的准确性。其次根据设计目标要求,设计了主要部件的功率参数,并提出了适合不同工作模式的车辆控制策略。然后基于Simulink软件平台,建立了前向式仿真模型。最后进行仿真试验,其结果分析表明,建立的电驱动系统模型有较好的动力性、经济性和平顺性,为燃料电池汽车整车研究提供了仿真平台。     

Effect of epidermal growth factor on follicle-stimulating hormone-induced proliferation of granulosa cells from chicken prehierarchical follicles

The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors, including follicle-stimulating hormone (FSH) and epidermal growth factor (EGF). In this study, the stage-specific effect of EGF on FSH-induced proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens. Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles, including the large white follicle (LWF) and small yellow follicle (SYF), and thereafter the expression decreased markedly to the stage of the largest preovulatory follicle. SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection. Subsequently the granulosa cells from SYF were cultured to reveal the mediation of EGF in FSH action. Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1–100 ng/ml). This result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis. Furthermore, EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR, FSH receptor, and the cell cycle-regulating genes (cyclins D1 and E1, cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor mRNA. However, the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478. In conclusion, EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell proliferation and retarded cell differentiation in the prehierarchical follicles. These expressions thus stimulated follicular growth before selection in the egg-laying chicken.     

便携式大容量太阳能锂离子电池充电器的设计

锂离子电池其高能量、高电压、长寿命、无污染等优势成为人们的首选。硅太阳能电池可分为单晶硅电池、多晶硅电池、非晶硅电池。锂离子电池的充电过程可分为三个阶段即恒流模式、恒压模式及涓流模式。为此我们利用多晶硅电池,非晶硅电池作为主要的充电能源,对锂离子或者锂-聚合物可充电电池通过电池管理芯片,实现可移动太阳能锂离子电池充电。     

基于模糊控制的智能变频空调控制系统研究

通过神经网络和模糊控制技术的结合,实现了模糊神经网络控制器FNNC和神经网络预测器NNP的结构设计。该设计可以提高压缩机的控制精度,加强控制系统的适应性,实现压缩机的智能化。