771 research outputs found

    The responses of photosynthetic performance in marine diatoms and green tide alga to ocean acidificaiton and other environmental factors

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    无中文摘要While increasing atmospheric CO2 concentration and associated ocean acidification have been predicted to stimulate marine primary production, little is known about the interplay between ocean acidification and other climate change parameters, such as shoaling of upper mixing layer (UML), associated with global warming. Here, we showed that the high CO2-grown cells showed higher growth rates at the...学位:博士后院系专业:海洋与环境学院环境科学与工程系_环境科学学号:201017004

    Analysis and Design of OA System for Primary Level Politics and Law Committee

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    随着信息技术的发展和网络技术的普及,近年来基层党委政法委计算机网络得到了快速发展。内部信息系统逐步发展和完善,各单位拥有大量宝贵的信息资源,也具备了对各级党委政法委和相关政法部门提供信息和应用服务的条件。用户对信息的需求和获取方式提出了新的更高的要求,信息交换方式网络化,可减少很多不必要的人工往返和重复工作,大大提高各部门的办事效率;利用网络化的信息技术为用户提供更快更好的服务。这些均表明实现政法机关内部电子化和信息化应用,实现办公自动化是大势所趋。构建基层政法委机关内部信息网,从而实现无纸办公,必将对政法委工作具有一定的推动作用。 基层党委政法委的工作,事关当前日益繁重的维护稳定工作,并承...With the development of information technology and the popularization of network technology, Primary Level Politics and Law Committee’s network are under development rapidly. Internal information system are unceasing development and perfection, each unit has a large number of valuable information resources, also have conditions to service all levels of Politics and Law Committee and the relevant d...学位:工程硕士院系专业:软件学院_工程硕士(软件工程)学号:X201023051

    Circular RNA CircHIPK3 Promotes NCI-H1299 and NCI-H2170 Cell Proliferation through miR-379 and its Target IGF1

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    背景与目的已有的研究证明:环状RNA是一类在哺乳动物中普遍存在的具有稳定闭合环状结构的内源性RNA分子。环状RNA; circHIPK3(circular RNA HIPK3, circHIPK3)在肝细胞癌(hepatocellular carcinoma,; HCC)中表达水平较高,促进肝癌细胞生长。但是其在非小细胞肺癌(non-small cell lung cancer,; NSCLC)中的作用及其调控机制尚无文献报道。本研究拟探讨环状RNA; circHIPK3对NSCLC细胞系NCI-H1299和NCI-H2170细胞增殖的影响,并进一步研究其调控的分子机制。方法Real-time; PCR法检测circHIPK3在NSCLC各细胞系中的表达水平。CCK-8实验和克隆形成实验检测过量表达和干扰circHIPK3对细胞增殖的影响; 。双荧光素酶报告基因实验分别检验miR-379与circHIPK3及miR-379与IGF1 mRNA的结合情况。Western; blot和ELISA检测细胞内外的IGF1蛋白表达水平。结果环状RNA; circHIPK3在6株NSCLC细胞株中均有表达,其中H1299表达最低,H2170表达最高,通过转染过表达的circHIPK3可显著促进NC; I-H1299细胞增殖,干扰circHIPK3可显著抑制NCI-H2170细胞增殖。miR-379可与circHIPK3及IGF1; mRNA直接结合。过表达circHIPK3导致IGF1表达量上调,干扰circHIPK3能够下调IGF1表达水平,转入miR-379; mimics恢复了circHIPK3稳转细胞株IGF1表达水平的上调及细胞增殖表型。结论环状RNA; circHIPK3在NSCLC细胞系NCI-H1299及NCI-H2170中可通过miR-379调控IGF1表达促进细胞增殖,环状RNA; circHIPK3可能成为非小细胞肺癌治疗的新靶点。Background and objective It has been proven that the circular RNA,; possessing a stable covalently closed continuous loop, is a type of RNA; molecule which is expressed widespread in mammals. The circular RNA; circHIPK3 is abundantly expressed in hepatocellular carcinoma (HCC) and; promotes tumourgenesis. However, a role for circHIPK3 has not been; systematically examined in non-small cell lung cancer (NSCLC). In this; study, we investigated whether circHIPK3 has an effect on cell; proliferation in the NSCLC cell lines NCI-H1299 and NCI-H2170 and the; underlying molecular mechanisms. Methods The expression of circHIPK3 was; measured by real-time PCR in NSCLC cell lines. Nuclear mass separation; experiment was used to detect the location of circHIPK3 in cells. The; gain and loss function experiments were used to examine the; proliferation of NCI-H1299 and NCI-H2170 cells by Cell Counting Kit-8; (CCK-8) and the colony formation assays. Then, circHIPK3 was cloned into; the downstream of the luciferase reporter gene which activity was; detected to verify whether miR-379 could bind with circHIPK3 or IGF1; mRNA. The protein level of IGF1 was detected by Western blot and ELISA; in circHIPK3 overexpressed/knock-down NCI-H1299 and NCI-H2170 cells.; Results CircHIPK3 was generally expressed in six kinds of NSCLC cells; lines we detected, and the expression level was highest in H2170 and; lowest in H1299. Overexpression of circHIPK3 obviously promoted; NCI-H1299 cell proliferation and knock-down of circHIPK3 inhibited; NCI-H2170 cell proliferation. In the luciferase assay, miR-379 was; observed to sequester circHIPK3 and IGF1 mRNA with potential binding; sites. Furthermore, we found that the overexpression of circHIPK3 could; increase the expression levels of IGF1 and knockdown reduced it.; Moreover, up-regulation of miR-379 rescued the phenotype induced by; overexpression of circHIPK3. Conclusion CircHIPK3 could promote cell; proliferation by a circHIPK3/miR-379 pathway in NCI-H1299 and NCI-H2170; cells and might be a potential tumor biomarker for NSCLC.国家自然科学基金项

    Survey of location-centric target tracking with mobile elements in wireless sensor networks

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    介绍目标跟踪的过程以及移动跟踪的特点;通过区分目标定位为主的方法和目标探测为主的方法,介绍定位为主的移动式目标跟踪方法(称为目标的移动式定位跟踪; )的研究现状;分析和比较不同方法的特点和应用领域,发现现有方法虽然可以提高跟踪质量、降低网络整体能耗,但是还存在一些问题。基于此,总结目标的移动; 式定位跟踪方法在方法类型、网络结构和节点模型等方面可能存在的研究热点,指出其研究和发展趋势。The basic process of target tracking and the properties of tracking; solutions with mobile elements were introduced. By distinguishing; location-centric methods and detection-centric methods, the current; research status of the location-centric target tracking methods were; reviewed. The properties and application fields of different solutions; were analyzed and compared. Although the existing solutions can; significantly improve tracking quality and reduce energy consumption of; the whole network, there are also some problems. Based on these; discoveries, some possible research hotspots of mobile solutions were; summarized in many aspects, such as method types, network architecture,; node model, and so on, indicating the future direction of research and; development.国家自然科学基金资助项目; 国家科技支撑计划项

    Research Advance of Target Tracking with Mobile Elements in Heterogeneous Wireless Sensor Networks

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    传统固定无线传感器网络在进行目标跟踪过程中面临跟踪质量较低、网络能耗较高等问题.引入移动节点后所组成的异构无线传感器网络提供了新的解决方法,即移; 动式目标跟踪.目前的研究大多对被跟踪目标的探测和定位混为一谈,本文区分了以探测为主和以定位为主的两类方法,着重介绍以探测为主的移动式目标跟踪方法; 的研究现状.通过对比现有方法在跟踪质量和网络能耗等方面的优缺点,揭示了现有研究存在的问题.总结了移动式目标跟踪领域存在的研究热点和趋势.Traditional stationary wireless sensor networks usually encounter some; problems during the process of target tracking,such as low tracking; quality, high energy consumption and so on. More and more mobile; elements, i. e., mobile sensors, are used to build up heterogeneous; wireless sensor networks and thus bring new solutionsfor target; tracking. Existing researches usually misidentify detecting the target; with locating the target. After distinguishing between detection-centric; and localization-centric methods,we review specifically the current; research status of the detection-centric target tracking methods. By; comparing existing methods'merit and demeritin aspects like tracking; quality, energy consumption, etc.,their problems are revealed.; Therefore, we summarize some possible research hotspotsand tendency of; mobile solutions in many aspects.国家自然科学基金重点项目; 国家科技支撑计划项目; 国家自然科学基金项目; 福建省自然科学基金计划项

    Establishment of a nude mouse model of glioma orthotopic xenograft with double-fluorescent labeling

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    目的建立一种稳定、可实时监测的胶质瘤原位移植瘤裸鼠模型。方法用带有荧光素酶(luciferase-Luc)和绿色荧光蛋白(green fluorescent protein-GFP)基因的慢病毒感染U251神经胶质瘤细胞,流式细胞仪筛选稳定表达GFP-Luc荧光的细胞系,并通过CCK-8实验、细胞周期实验、Transwell肿瘤迁移及侵袭实验等评价荧光细胞的增殖、迁移和侵袭能力是否改变;将细胞接种至裸鼠大脑尾状核,建立胶质瘤原位移植瘤模型,利用小鼠活体成像系统监测脑内肿瘤的生长情况,并通过石蜡切片,HE染色评价细胞在裸鼠脑内的病理特征及成瘤能力。结果成功构建稳定表达GFP荧光和luciferase荧光的U251胶质瘤细胞系及动物模型,慢病毒整合并未改变细胞的增殖、迁移及侵袭能力;模型生长周期适中,成瘤率高,瘤体在颅内生长稳定,HE切片符合人胶质瘤特征。结论双荧光标记的胶质瘤细胞相比于传统细胞更有利于胶质瘤动物模型的实验研究;U251-GFP-Luc胶质瘤细胞裸鼠模型,其肿瘤生长和病理特性与人胶质瘤相似,且可实时观察肿瘤生长,可作为胶质瘤实验研究的理想动物模型。Objective To establish a stable and real-time monitorable nude mouse model of orthotopic glioma xenograft. Methods U251 glioma cell line was infected by a leutiviral vector containing green fluorescent protein (GFP) and luciferase (Luc) gene. Ceils stably expressing fluorescence of GFP and Luc were sorted by flow cytometry. CCK-8 test and Transwell tumor invasion and migration assay were used to compare the biological features between the ceils stably expressing GFP-Luc fluorescence and cells without fluorescence. Then the ceils were implanted intracranially in the right caudate nucleus of athymic BaIb/c nude mice to establish the tumor model. The growth of intracerebral tumor was monitored over time by a bioluminescence imaging (BLI) system. Hematoxylin-eosin (HE) staining was used to evaluatethe histopathological features and tumorigenicity of the transplanted glioma cells in the brain of nude mice. Results U251 glioma cell line with stably expressing GFP-Luc fluorescence and the corresponding orthotopic xenograft model were successfully established. There was no statistically significant difference in the proliferation, invasion and migration abilities between the cells with stably expressing GFP-Luc fluorescence and the control cells. This model showed a high tumor formation rate and stable tumor growth, and takes a moderate time to establish this model. Conclusions Compared with the traditional glioma cells, GFP-Luc-transfected human glioma cells are more feasible for the studies of glioma in vivo. The tumor growth and pathological characteristics in this U251-GFP-Luc glioma model are similar to human glioma, and the growth of this tumor can be real-time monitored. It can be used as an ideal animal model for experimental studies of glioma.国家自然科学基金(编号:30970733)

    Survey on Connectivity with Mobile Elements in WSNs

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    节点连通性是无线传感器网络研究的热点问题之一,然而由于节点能量耗尽、硬件故障以及通信链路失效等问题的存在,造成网络分割,因此如何确保网络连通成为; 无线传感器网络亟待解决的关键性问题.近年来,一个新的研究趋势是通过引入计算能力较强且能量较为充足的移动性节点来进行连通控制,提高无线传感器网络的; 整体性能.本文对目前利用移动性节点的主流连通控制方法进行了充分调研,通过对这些方法的详细分类和比较,归纳了移动式连通控制的各类方法的特点,分析了; 这些方法的性能和适用范围,总结了研究中存在的主要问题与挑战,并指出了未来可能的研究方向.The connectivity of sensors is one of the main research problems in; wireless sensor networks (WSNs).Data can be forwarded through connected; sensor nodes.However,becauseof energy depletion,hardware failure and; communication link failure,the network may be partitioned.How to; guarantee the connectivity becomes an urgent issue in wireless sensor; networks.Traditional work usually focuses on maximizing the connectivity; with minimum sensors.In recent years,a new research trend is to utilize; mobile elements for connectivity control.Since the mobile element is; more powerful than normal sensors,it improves the performance of many; aspectsin wireless sensor networks.In this paper,we makea comprehensive; investigation about the current major connectivity control methods with; mobile elements.We first summarize the characteristics of mobile; topology control methods via a new classification.Based on the; classification,these methods are compared to each other according to a; serial parameters.Finally,we analyze the performances and the; application scopes of these methods,summarize the main problems,and; point out the future research directions.国家"九七三"重点基础研究发展计划项目; 国家科技支撑计划项目; 国家自然科学基金项目; 福建省科技计划重点项目; 福建省自然科学基金计划项

    职业生涯规划教育提高学生学习素质的理念与途径

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    随着高等教育规模扩大,毕业生就业竞争日益激烈,大学生职业生涯规划教育越来越受到广大教育者和学生的关注。但是如何完善职业生涯规划教育,满足大学生和社会需求是一个严峻的课题,该文就职业生涯规划教育提高学生学习素质的理念和途径进行了初步探讨。福建省教育厅B类社会科学研究项目(JBS09102

    Application of carbon materials in lithium-air battery and its development

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    作者简介:武巍(1984—),男,河北省人,硕士生,主要研究方向为 锂空气电池。 联系人:杨勇,Email: [email protected][中文文摘]综述了有关锂空气电池所应用的碳材料的种类及其性能,总结了不同种类碳材料的物理参数,如比表面积、孔体积、粒子尺度以及电导性等对锂空气电池性能的影响规律;以及碳材料改性对锂空气电池氧电极的性能改善。已有的文献数据表明用于锂空气电池的碳材料必须具有较好的导电性、较大的比表面积、合适的孔体积和粒子尺度等。这些物理化学参数为应用于锂空气电池的碳材料的选择提供了依据。[英文文摘]The different types and physical properties of carbon materials used in lithium-air battery field were summarized, and the influence of the various physical parameters of carbon materials on the performance of lithium air battery were discussed, such as specific surface area, pore volume, particle size and conductivity. The research progress in the modifications of carbon materials was also simply summarized. It is concluded that carbon with good electrical conductivity, large surface area, appropriate pore volume and particle size are necessary, which governs the electrochemical performance of oxygen cathode. These physical parameters can be the basic criteria for selection of carbon material as cathode material in lithium air batteries.基金项目:国家“973”计划课题资助(2011CB935903

    Survey on Coverage Control with Mobile Elements in Wireless Sensor Networks

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    在无线传感器网络中,节点能量限制、硬件以及通信链路故障等问题,造成网络空洞的产生且影响了网络的正常运作,因此如何确保网络覆盖率成为传感器网络中需; 要解决的重要问题.近年来,通过引入移动节点来进行覆盖控制,提高传感器网络的覆盖率成为一个新的研究趋势.本文通过充分调研利用移动节点进行网络覆盖控; 制的方法,并对其进行了分类和比较,归纳了移动式网络覆盖的各种方法的特点,分析这些方法的性能和适用范围,总结存在的主要问题,并指出未来的研究方向.Due to the existence problems of energy depletion,hardware failure and; communication link failure and so on,which causes network holes and; affects the normal network operation. The insurance of coverage becomes; an urgent issue in wireless sensor networks. In recent years, a new; research trend is to utilize mobile nodes for coverage control, which; increases the coverage of wireless sensor networks. In this paper, we; have a comprehensive investigation about the current major topology; control methods with mobile nodes,and summarize the characteristics of; mobile topology control methods via classification and comparison of; these methods. Finally,we analyze the performances and the application; scopes of these methods, summarize the main problems,and point out the; future research directions.国家自然科学基金重点项目; 国家科技支撑计划项目; 国家自然科学基金项目; 福建省科技计划重点项
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