海洋酸化对优势固氮蓝藻束毛藻的影响及其机理

由人为活动排放的二氧化碳（CO2）而引起的海洋酸化,预计将影响对热带、亚热带海域的初级生产力有显著贡献的固氮浮游植物。本研究揭示了海洋酸化对优势固氮蓝藻束毛藻（Trichodesmium spp.）的生长和固氮的影响及其机理。研究表明,虽然海洋酸化中的CO2升高对束毛藻有促进效应,但酸化的整体效应为抑制其固氮和生长。究其原因,海洋酸化引起束毛藻胞质pH下降,从而降低固氮酶效率、干扰胞内pH稳态、影响细胞产能。在铁限制条件下,由于有限的铁难以满足束毛藻响应海洋酸化胁迫所做出的生理响应,因而铁限制加剧了海洋酸化对束毛藻的负面影响

Preparation,characterization,and application of monoclonal antibodies against human decoy receptor 3

目的制备抗DcR3单克隆抗体(mAb),鉴定其生物学特性,并应用于ELISA、Western blot、Flowcytometry(FCM)检测。方法以纯化的可溶性DcR3(sDcR3)免疫Balb/c小鼠,采用杂交瘤技术制备抗DcR3 mAb。用Ig亚类ELISA试剂盒鉴定抗DcR3mAb的亚类。用ELISA方法测定抗DcR3 mAb与sDcR3结合的特性,SDS-PAGE鉴定抗DcR3 mAb与SW480细胞上清中DcR3结合的特性,以鉴定mAb的特性。用间接ELISA法检测腹水mAb的效价、亲和常数并进行表位分析。Western blot检测mAb的特异性及应用,并用所获抗DcR3单克隆抗体(mAb)通过流式细胞仪检测肿瘤细胞表面DcR3的表达水平。结果获得4株可分泌DcR3 mAb的杂交瘤细胞系ZZ-393、ZZ-394、ZZ-151和ZZ-268。其中DcR3 mAb ZZ-268(下文简称为ZZ-268)的Ig亚类为IgG1(κ型);腹水效价为1×10-5;亲和常数为1.28×109水平;ZZ-268和ZZ-151可识别与其他2种抗体不同的抗原表位;Western blot证实,获得的ZZ-268... 【英文摘要】 Objective To prepare monoclonal antibodies mAb against DcR3,characterize their biological properties and apply them to ELISA,Flow cytometry,and Western blot detection.Methods Balb/c mice were immunized with soluble DcR3(sDcR3) for preparing mAb by using hybridoma technique.Ig subclass and specificity of mAbs were analyzed by ELISA and SDS-PAGE,respectively.The titres,relative affinity,and epitopes of mAbs in ascitic fluid were determined by indirect ELISA.The specificity and application of mAb were detected...厦门大学科研启动资金(Z03103);; 厦门市科技计划项目(3502Z20083008)资

TPU/POE共混体系相分离过程的ATR-FTIR研究

探讨了一种新的共混体系热塑性聚氨酯(TPU)/聚乙烯-辛烯共聚物(POE)共混体系,在相分离过程中衰减全反射傅里叶变换红外光谱(ATR-FTIR),结果发现:对于不相容TPU/POE体系,随着热老化时间的增加,ATR-FT-IR特征峰面积也逐渐增加(温度较低除外),温度较高时则先增加后降低;而PU/POE/POE-g-MA体系,由于加入相容剂,ATR-FTIR特征峰面积则随着热老化时间的增加而逐渐降低

Reduced nitrogenase efficiency dominates response of the globally important nitrogen fixer Trichodesmium to ocean acidification

工业革命以来，海洋吸收了约三分之一人为排放的CO2，以迄今3亿年来最快的速度酸化（CO2升高、pH下降），这势必影响海洋生态系统的关键过程和功能。研究团队创新性地从区分海洋酸化过程中CO2上升和pH下降的双重效应入手，揭示了海水CO2升高的正效应小于pH下降的负效应，故酸化的净效应为抑制束毛藻的固氮作用。这是因为酸化引起束毛藻胞质 pH下降，从而降低固氮酶效率、干扰胞内pH稳态、影响细胞产能。在上述研究工作的基础上，进一步系统地测定了固氮和光合系统蛋白的表达量及其含铁量，建立了一个束毛藻的“资源最优化分配”细胞模型。实现了实验数据和数值模型的紧密结合：实验数据是构筑模型的坚实基础，并提高了模型的预测水平；通过模型模拟，加深了对实验发现的认知，并对实验结论进行了时空拓展。 罗亚威博士和史大林博士为论文的共同第一作者和共同通讯作者，史大林课题组的洪海征教授、研究助理沈容和博士生张福婷为共同作者。论文的共同作者还包括美国佛罗里达州立大学助理教授Sven Kranz博士和乔治亚大学副教授Brian Hopkinson博士。【Abstract】The response of the prominent marine dinitrogen (N2)-fixing cyanobacteria Trichodesmium to ocean acidification (OA) is critical to understanding future oceanic biogeochemical cycles. Recent studies have reported conflicting findings on the effect of OA on growth and N2 fixation of Trichodesmium. Here, we quantitatively analyzed experimental data on how Trichodesmium reallocated intracellular iron and energy among key cellular processes in response to OA, and integrated the findings to construct an optimality-based cellular model. The model results indicate that Trichodesmium growth rate decreases under OA primarily due to reduced nitrogenase efficiency. The downregulation of the carbon dioxide (CO2)-concentrating mechanism under OA has little impact on Trichodesmium, and the energy demand of anti-stress responses to OA has a moderate negative effect. We predict that if anthropogenic CO2 emissions continue to rise, OA could reduce global N2 fixation potential of Trichodesmium by 27% in this century, with the largest decrease in iron-limiting regions.This work was funded by the National Key R&D Program of China (2016YFA0601404 and 2016YFA0601203), NSFC (41476093, 41721005, 41890802, 31861143022 and 41376116), and the MEL internal research fund (MELRI1502).本项研究得到了国家重点研发计划（2016YFA0601404 和2016YFA0601203）以及国家自然科学基金系列项目（41476093, 41721005, 41890802, 31861143022 和41376116）的资助

纪念五四宪法颁布暨全国人民代表大会成立五十周年理论研讨会纪要

今年 9月是五四宪法颁布、全国人民代表大会成立五十周年。五四宪法是新中国的第一部宪法 ,为我国的社会主义民主法制奠定了基础 ,具有划时代的意义。坚持和完善人民代表大会制度 ,是新的历史条件下推进政治体制改革和社会主义政治文明建设的重要内容。基于“以学术表达纪念、以纪念促进学术”的目的 ,中国社会科学院法学研究所于 2 0 0 4年 9月 5日举办了“纪念五四宪法颁布暨全国人民代表大会成立五十周年理论研讨会”。来自全国各地的 70余位代表莅临会议 ,研讨了诸多热点和前沿问题

第十八届美国理论与应用力学大会总结

1会议概况2018年6月5—9日,第18届美国理论与应用力学大会(18th U.S. National Congress of Theoretical and Applied Mechanics, USNCTAM2018)在美国芝加哥召开.本次大会由美国力学国家委员会和中国力学学会联合主办,旨在探讨和交流近四年世界范围内在理论和应用力学领域的基础研究、创新技术的最新进展,吸引了来自世界各地的近千名专家学

Supervision of Local Financial Expenditure Deviation Degree:Based on Factor Analysis

通过对2010年全国36个省、自治区、直辖市和计划单列市按政府功能分类的财政支出预决算偏离度进行因子分析,建立了双因子的支出偏离度的分析体系。研究结果表明,根据因子得分进行的各地区支出偏离度排序和聚类树分析,显示了我国财政支出偏差的格局;主因子的置信监控界定了地区偏离度的适度性区间,发现地方政府的财政支出偏离度仍在可控范围之内。可见,以政府的支出结构为测度,基于统计数据的监督体系,有助于考核地方政府财政职能改革发展的绩效。Through a factor analysis of the financial expenditure budget and final budget deviation degree classified by the government functions of 36 provinces,autonomous regions,municipalities and municipalities with independent planning status in China in the year of 2010,this study establishes an analytical system of the expenditure deviation degree with the double factors.The results reveal that the order of the expenditure deviation degree of different regions according to their factor scores and the analysis of the clustering tree show the situation of China's financial expenditure deviation degrees.The confidence monitoring of the major factors defines the interval of appropriateness of the regional deviation degree;it reveals that the financial expenditure deviation degrees of the local governments are still under control.It is thus clear that the supervision system with government financial expenditure structure as the measure and based on the statistical data are beneficial to the measurement of the performances of the reform and development of local governments' financial functions.国家社会科学基金重大招标项目“健全公共财政体系研究”(10ZD&036

Tax Competition and Hypothesis of Economic Growth Threshold:An Analysis Based on China's Empirical Data

税收竞争对经济增长的影响存在积极效应和消极效应,它主要通过影响企业决策和公共服务的提供而作用于经济增长。通过对经济增长门槛假说的检验发现:在经济发展水平较高的地区,税收竞争的积极效应大于其消极效应,促进经济增长;而在经济发展水平较低的地区,税收竞争的积极效应小于其消极效应,抑制经济增长。此外,研究结果还表明:中国并未出现恶性的税收竞争,但各地区的税收负担与经济发展水平不相适应。可见,地方政府只有合理利用税收竞争手段,才能促进地方经济的可持续发展。Tax competition has both positive and negative impacts on economic growth, and this impact on economic growth is mainly exerted through affecting corporate decision and the provision of public service.Through the test of the hypothesis of economic growth threshold, this paper finds that the positive effect of tax competition is greater than its negative effect in regions with higher level of economic development, and thus promoting economic growth.While in regions with lower level of economic development, the positive effect is smaller than the negative one, therefore restraining economic growth.In addition, the result also shows that there is actually no vicious tax competition in China yet, but the regional tax burden is not consistent with the local economic development.It is thus clear that only by making rational use of tax competition means can local governments achieve sustainable development of local economy.福建省软科学项目“加速区域经济增长的研发激励政策研究”(2012R0079); 国家社会科学基金重大项目“健全公共财政体系研究”(10ZD&036

利用旋涡发生器减小大跨方形平屋盖风吸力的实验研究

在强风作用下，屋盖作为风敏感部位往往最先发生破坏，如何抑制屋盖上的极值负风压是保障大跨建筑抗风安全的关键。基于此，提出一种简单有效的新型屋盖抗风气动措施。在平屋顶屋檐处安装旋涡发生器(PVG)，通过旋涡发生器的扰流作用来减小屋盖极值风压。采用风洞测压试验研究在不同风向角下PVG对屋面极值风压的气动控制效果，分析PVG对屋顶流场结构的影响并探讨PVG的工作机理。研究结果表明：PVG可以有效减小平屋盖屋面极值风压，尤其在倾斜风向角下的减压效果显著。在最不利风向角下，屋盖极值风压最大减小幅度可达73.3%。相对于长度来说，PVG高度对屋面风压的影响更明显，较密的安装间距和适宜的安装角度可以更好地降低屋盖风吸力。在安装PVG后，屋盖锥形旋涡的涡核位置和再附位置发生改变，屋顶风压低频部分能量占比大幅度减少，脉动能量减弱，大尺度旋涡减少，而小尺度的湍流造成的脉动能量成分增加。The roof, as a wind-sensitive part, is often the first to suffer damages during strong wind events. How to mitigate the extreme negative wind pressure on the roof is the key to ensure the safety of the buildings. Consequently, a simple-effective new device, passive vortex generators(PVG), to mitigate extreme wind pressure was proposed. By the disturbing effect of the PVGs, they were installed at the eaves of flat roofs to reduce the roof extreme wind pressure. The aerodynamic control effects of PVGs on roof extreme wind pressure were presented at different wind angles. The effects of PVGs on flow field as well as their control mechanism were analyzed and discussed. The results show that the PVGs can effectively reduce the wind pressure on the flat roof, particularly at nonzero wind angles. At the most unfavorable wind angle, the maximum reduction in roof extreme wind pressure can be up to 73.3%. Compared with the length, the PVG height has a more obvious effect on mitigating the roof suction. A denser installed spacing and a suitable installed angle can better reduce the roof wind pressure. After installing the PVGs, the position of the vortex core and the reattachment position of the conical vortex are highly modified. The low-frequency portion of the wind pressure fluctuation energy is significantly reduced, and the total fluctuation energy is weakened. The large-scale vortices are then reduced, while the small-scale turbulence component is increased

乘用车变速箱箱体低噪声方法的研究

为了改善汽车变速箱振动噪声问题，利用Romax建立变速器传动系统动力学模型，仿真得出变速箱工作时的轴承动态力；对建立的有限元箱体模型进行模态分析，得知箱体比较薄弱区域；由动力学仿真的轴承动态力作为壳体振动响应分析的激励，分析壳体的振动特性；以壳体振动加速度为边界条件，在壳体声学边界元模型基础上利用模态声学传递法计算壳体外声场辐射噪声。通过分析模态参与因子和模态声学贡献量，确定对壳体振动噪声贡献较大的模态，在相应模态振动敏感处优化。结果表明，优化后壳体的振动噪声有所下降，辐射噪声下降了1.4 dB