南极海冰区冰藻类群及兴衰过程

本文总结了国际上对南极冰藻类群及其生理生态特性的多年研究成果 ,结合我国科学家在南极长城站以及在戴维斯和中山站的越冬研究 ,阐述了南极海冰区的冰藻类群及其形成机理 ,对冰藻的形成、存活、旺发和消亡过程进行讨论 ,并对大洋浮冰区和近岸固定冰区冰藻类群的生态特性进行对比 ,提出了今后有待进一步深入研究的领域 【英文摘要】 Combining with the research results obtained from the Great Wall and Zhongshan Stations of China, the thesis reviews the different ice algal assemblages occurring in the Antarctic sea ice and their formation, survival, growth and disappearance, compares the difference between the pack and fast sea ice zones and brings forward some scientific questions which are needed for further research. There are surface, interior, bottom and sub ice assemblages within ice, and each composes of some types. Because of ...国家自然科学基金项目 ( 30 2 70 112 ;4 0 0 0 6 0 10 )资

The progress in the study of Arctic pack ice ecology

The sea ice community plays an important role in the Arctic marine ecosystem. Because of the predicted environmental changes in the Arctic environment and specifically related to sea ice, the Arctic pack ice biota has received more attention in recent years using modern ice-breaking research vessels. Studies show that the Arctic pack ice contains a diverse biota and besides ice algae, the bacterial and protozoan biomasses can be high. Surprisingly high primary production values were observed in the pack ice..

雷帕霉素衍生物对胰岛的毒性研究

目的探讨雷帕霉素及其衍生物依维莫司、地磷莫司、佐他莫司对胰岛的毒性作用。方法采用小鼠胰岛素瘤细胞(MIN6)作为体外研究胰岛细胞的对象,分别在含有依维莫司、地磷莫司、佐他莫司的培养基中孵育MIN6细胞48小时,通过Brdu检测细胞增殖、CCK8检测细胞活力、PI检测细胞周期、流式细胞术检测细胞凋亡以及ELISA检测细胞分泌胰岛素功能,观察3种雷帕霉素衍生物对MIN6细胞的影响。结果我们发现3种雷帕霉素衍生物均会对MIN6细胞的增殖和活力产生抑制作用。在细胞周期和凋亡实验中,与阴性对照组比较,3种衍生物对MIN6细胞的影响呈现抑制G1期向S期转变的趋势和促进细胞凋亡的趋势,但差异没有统计学意义。另外,3种衍生物与雷帕霉素一样,均可减少MIN6细胞分泌胰岛素,差异具有统计学意义。结论雷帕霉素及其衍生物依维莫司、地磷莫司、佐他莫司均对胰岛产生一定毒性。国家自然科学基金项目(31271038,81302546

The abundance and diversity of nanoplankton in Arcitic Ocean

近年来随着全球气候变化对北冰洋生态环境的影响日益显现,北极微型浮游生物生态学研究得到了广泛的重视和实质性的进展。对北冰洋微型浮游生物的主要类群:异养细菌、古菌、光合异养原核生物和微型真核生物的分布及其多样性研究进展做了概述,并在此基础上展望了未来北冰洋微型浮游生物学研究。Asthe most abundant and the most taxonomically and genetically diverse organisms in the marine ceosystem,nanoplankton predominate in the marine system concerning their bioactivity,biomass,and production.They play an important role in the carbon fixation process in the Arctic Ocean,and are an important component to regulate the biosphere.Furtherly,nanoplankton can be an important indicator of the changing environment,since the changes in the community,structure and biomass of nanoplankton reflect the changes in the pathways of nutrient and energy transferring in the food web and the changes in the biogeochemical cycle.Recently,ecology study of the Arctic nanoplankton has been paid more attention due to the increasing impacts of climate change on the Arctic marine ecosystems.Substantial progress has been achieved.The Arctic heterotrophic bacteria were reported to resemble those in the seas of lower altitudes in their high abundance and biomass with seasonal successions.Particle-associated bacteria often show a higher specific metabolic activity than the free-living communities.So far,there are few reports on the proteorhodopsin(PR)-containing bacteria.High diversity has been reported for this group in the Chukchi Sea,which can be attribute to yariable bacteria communities.A large number of aerobic anoxygenic phototrophic(AAP) bacteria have been found in the Chukchi Sea with a distinctly seasonal succession.The photosynthetic group in the Arctic Ocean was found to be mostly composed with the nanoplankton(≤20μm),described as a polar ecotype of the small prasinophyte Micromonas.The high correlation between the abundance of coccoid cynaobacteria and temperature results their low abundance at the high latitudes There are only a few studies of Synechococcus in the coastal Arctic Ocean.The Micromonas is proved to be ubiquitous throughout the Arctic Ocean,especially at the chlorophyll-maximum layer,and may be a major contributor to the primary production in the Arctic Ocean.Until now little is known about the distribution of heterotrophic nanoflagellates in the Arctic Ocean,compared with phytoplankton and prokaryotes.Many scientific questions,which deserve special attention,remain unsolved due to lack of continuous sampling and the complexity of the nanoplankton characteristics.Some of them have been highlighted here in the Arctic nanoplankton ecology.(1) More attention should be paid to the effect of the climate change on the nanoplankton community in the Arctic Ocean,considering its major and often dominant contribution to the total ecosystem.(2)Most of the investigations of nanoplankton community are focused on the Atlantic Arctic Ocean of the Arctic Ocean.It is necessary to investigate the community structure of the nanoplankton in the entire Arctic Ocean.(3) As a photoheterotrophic microbe,AAP bacteria may play a special role in the ecology in the Arctic Ocean.However,little is known about the distribution,abundance,and diversity of the AAP bacteria in Arctic Ocean.(4)Archaea seems to be of special significance in the Arctic waters with large population existing in the surface water.More work need to be done on their diversity and their functions in the energy flow.国家自然科学基金(40576002;41076130);国家海洋局青年基金项目(2010116

田基黄中三个黄酮类化合物保肝退黄作用的实验研究

【目的】研究田基黄中槲皮苷(Quercetin-3-β-D-rhamnose)、异槲皮苷(Quercetin-3-β-D-glucoside)、田基黄苷(Quercetin-7-β-D-rhamnose)3个黄酮类化合物的保肝退黄作用。【方法】选用四氯化碳(CCl4)和D-氨基半乳糖胺(D-Gal)致大鼠急性肝损伤模型,观察3个黄酮类化合物对血清丙氨酸转氨酶(ALT)、门冬氨酸转氨酶(AST)的影响;用α-萘异硫氰酸酯(ANIT)致小鼠黄疸性肝损伤模型,观察3个黄酮类化合物对血清总胆红素(T.BIL)的影响。【结果】异槲皮苷、槲皮苷、田基黄苷均能显著抑制CCl4和D-Gal所致的大鼠血清ALT和AST升高,对ANIT所致的小鼠血清总胆红素升高有明显的降低作用。【结论】田基黄中3个黄酮类化合物异槲皮苷、槲皮苷、田基黄苷均有保肝退黄作用

那格列奈对2型糖尿病患者空腹游离脂肪酸的影响

【目的】探讨那格列奈对初诊2型糖尿病患者空腹游离脂肪酸的影响。【方法】42例从未进行降糖及降脂药物治疗的初诊2型糖尿病患者，随机分为那格列奈组及瑞格列奈组各21例，测定空腹游离脂肪酸（FFA）及空腹血糖（FPG）、标准餐后2h血糖（2hPG）、血脂谱，次日行静脉葡萄糖胰岛素释放试验（IVG-IRT）后，分组给予那格列奈60～90mg或瑞格列奈0．5～1．0mg，双盲治疗12周后，重复前述检查。【结果】37例完成试验，那格列奈组（18例）空腹FFA从（0．47±0．18）mmol／L下降到（0．36±0．16）mmol／L，平均下降（0．11±0．21）mmol／L（P〈0．05），瑞格列奈组（19例）空腹FFA无显著变化，那格列奈组比瑞格列奈组空腹FFA降低有明显差异。两组患者血脂谱无明显变化，治疗后FPG、2hPG、HbAlc及胰岛素抵抗指数较治疗前均有明显下降（R0．05）．胰岛B细胞功能指数（HOMA-B）、IVG-IRT 10min内急性胰岛素反应（AIR）均有明显增加（P〈0．05），组间比较无明显差异（P〉0．05）。【结论】那格列奈有降低空腹游离脂肪酸的倾向，其机制可能独立于改善胰岛功能之外

Heat Dissipation Modeling Research of High Power LED Spot Lamp for Lighting

散热问题是lEd灯具成为新一代照明光源亟待解决的关键问题之一。提出一种lEd灯具散热建模方法:选用lEd射灯作为代表产品进行散热建模研究,采用三维造型软件建立lEd灯具产品三维模型,然后导入有限元流体热分析软件(Cfd)进行热仿真。研究散热仿真过程中的热阻设置、热量载荷计算和边界条件设定等关键问题,并求解lEd射灯的工作温度分布情况;将仿真分析结果与实验室测试数据进行对比分析研究。研究结果表明,运用该方法可以对室内照明lEd灯具进行较为准确的散热分析,仿真温度误差在4℃左右,仿真结果对灯具开发设计具有重要参考价值。Heat dissipation is one of the key problems need to be solved for LED lamps as a new generation of lighting light.A heat dissipation modeling method was presented for the LED lamp.The LED spot lamp was selected for dissipative research,3D models were established by modeling softwares,then the models were transferred into finite element thermal analysis software(CFD) for simulation.Several key aspects such as thermal resistance setting,heat load calculation and boundary conditions were considered in the analysis process,and the simulation result was compared with laboratory test data.The results show that the method can be used for accurate thermal analysis simulation of indoor LED lighting,with the temperature error less than 4 ℃,and the simulation result is of a great reference value for lighting design.国家科技支撑计划项目(2011BAE01B10); 国家高技术研究发展计划(863计划)资助项目(2011AA03A109

改革开放:中国电影的艺术成就与文化表达

钟大丰在市场化进程中探索中国电影学院的追求回顾我们改革开放四十年,从中国的范围来讲,是一个不断走向商品市场开放的过程。电影的发展和市场开放的进程有着特别紧密的关系,当我们跟改革开放的总体进程结合得比较紧的时候,我们会看到电影表现出活力;当我们离开改革开放进程相对比较远的时候,它的活力就会减少,问题就会出现,改革开放这四十年并不一直是一帆风顺的。很多人对80年代的活跃局面很怀念,那个时

LBO的腔内倍频特性研究

从倍频转换效率公式和腔内倍频的稳定态条件出发,得到倍频波的功率密度公式,进而得出倍频晶体最佳长度和倍频波最大功率密度的表达式。以LBO晶体Ⅰ类临界相位匹配腔内倍频946 nm为例,根据倍频波的功率密度公式,从理论上讨论了LBO长度、功率密度比对倍频波功率密度的影响,为LBO倍频产生473 nm蓝光实验提供了理论指导。虽然这里只是讨论了LBOⅠ类临界相位匹配倍频946 nm,但对所有腔内倍频实验(不同倍频晶体或不同倍频频率)具有借鉴作用