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    题名 作者 年代 出处 被引量
1Association of PINK1 and DJ-1 confers digenic inheritance of early-onset Parkinson's disease显示文摘Tang B Xiong H Sun P Zhang Y Wang D Hu Z Zhu Z Ma H Pan Q Xia JH Xia K Zhang Z 2006中国生物学文摘2006,20,8:30
2Kinematics and Dynamics of Deployable Structures with Scissor-Like-Elements Based on Screw Theory显示文摘Because the deployable structures are complex multi-loop structures and methods of derivation which lead to simpler kinematic and dynamic equations of motion are the subject of research effort, the kinematics and dynamics of deployable structures with scissor-like-elements are presented based on screw theory and the principle of virtual work respectively. According to the geometric characteristic of the deployable structure examined, the basic structural unit is the common scissor-like-element(SLE). First, a spatial deployable structure, comprised of three SLEs, is defined, and the constraint topology graph is obtained. The equations of motion are then derived based on screw theory and the geometric nature of scissor elements. Second, to develop the dynamics of the whole deployable structure, the local coordinates of the SLEs and the Jacobian matrices of the center of mass of the deployable structure are derived. Then, the equivalent forces are assembled and added in the equations of motion based on the principle of virtual work. Finally, dynamic behavior and unfolded process of the deployable structure are simulated. Its figures of velocity, acceleration and input torque are obtained based on the simulate results. Screw theory not only provides an efficient solution formulation and theory guidance for complex multi-closed loop deployable structures, but also extends the method to solve dynamics of deployable structures. As an efficient mathematical tool, the simper equations of motion are derived based on screw theory.SUN Yuantao WANG Sanmin MILLS James K ZHI Changjian 2014Chinese Journal of Mechanical Engineering2014,27,4:19
3A BAC clone of MDV strain GX0101 with REV-LTR integration retained its pathogenicity显示文摘The complete genome of Marek's disease virus (MDV) strain GX0101, which was integrated with the LTR sequences of REV, was cloned in Escherichia coli as a bacterial artificial chromosome (BAC). BAC vector sequences were introduced into the US2 locus of the MDV genome by homologous recombination. The viral DNA containing the BAC vector was used to transform Escherichia coli strain of DH10B. Then the recombinant virus was successfully rescued by transfection of the recombinant BAC DNA into primary chicken embryo fibroblast (CEF). This BAC viral clone was named bac-GX0101. When the reconstituted virus was inoculated into 1-day-old birds, visceral tumors could be detected as early as 62 d post infection. There was no difference in growth ability and pathogenicity to birds between the BAC derived virus and its parental virus. The BAC derived virus maintained its oncogenicity and immunosuppressive effects. In conclusion, the complete genome of GX0101 strain was successfully cloned into BAC and the infectious clone was rescued. With the powerful BAC manipulation system, the infectious clone will provide a useful tool for further understanding the functional roles of the inserted REV-LTR sequence in the GX0101 strain of MDV.SUN AiJun LAWRENCE Petherbridge ZHAO YuGuang LI YanPeng NAIR Venugopal K CUI ZhiZhong 2009Chinese Science Bulletin2009,54,15:15
4荧光寿命的快速傅里叶变换拟合方法显示文摘介绍了一种利用快速傅里叶变换算法对稀土掺杂物质的荧光寿命进行数据拟合的方法。稀土掺杂物质可用来制备多种光学传感器 ,用于温度、pH值等多种参量测量领域。本方法利用快速傅里叶变换 (FFT)结果作为基础 ,从非零项的相位角的正切值得出被测的荧光寿命 ,具有速度快、误差小、不受本底干扰等一系列优点。以掺铒光纤为例 ,通过数字仿真将本方法与其它几种传统的拟合方法进行了比较。快速傅里叶变换方法的测量偏差不到Prony方法的 5 0 % ,为对数似合 (log fit)方法测量偏差的 1/6。另外 ,快速傅里叶变换方法由于不受本底噪声影响 ,可以不必在信号处理时去掉本底噪声 ,因而可以明显缩短测量时间。孙伟民 张建中 于蕾 王晶菲 相艳荣 张扬 苑立波 Grattan K TV Sun T 2004光学学报2004,24,6:13
5A proposed surface resistance model for the Penman-Monteith formula to estimate evapotranspiration in a solar greenhouse显示文摘Greenhousing is a technique to bridge season gap in vegetable production and has been widely used worldwide. Calculation of water requirement of crops grown in greenhouse and determination of their irrigation schedules in arid and semi-arid regions are essential for greenhouse maintenance and have thus attracted increased attention over the past decades. The most common method used in the literature to estimate crop evapotranspiration(ET) is the Penman-Monteith(PM) formula. When applied to greenhouse, however, it often uses canopy resistance instead of surface resistance. It is understood that the surface resistance in greenhouse is the result of a combined effect of canopy restriction and soil-surface restriction to water vapor flow, and the relative dominance of one restriction over another depends on crop canopy. In this paper, we developed a surface resistance model in a way similar to two parallel resistances in an electrical circuit to account for both restrictions. Also, considering that wind speed in greenhouse is normally rather small, we compared three methods available in the literature to calculate the aerodynamic resistance, which are the r_a^1 method proposed by Perrier(1975a, b), the r_a^2 method proposed by Thom and Oliver(1977), and the r_a^3 method proposed by Zhang and Lemeu(1992). We validated the model against ET of tomatoes in a greenhouse measured from sap flow system combined with micro-lysimeter in 2015 and with weighing lysimeter in 2016. The results showed that the proposed surface resistance model improved the accuracy of the PM model, especially when the leaf area index was low and the greenhouse was being irrigated. We also found that the aerodynamic resistance calculated from the r_a^1 and r_a^3 methods is applicable to the greenhouse although the latter is slightly more accurate than the former. The proposed surface resistance model, together with the r_a^3 method for aerodynamic resistance, offers an improved approach to estimate ET in greenhouse using the PM formula.GONG Xuewen LIU Hao SUN Jingsheng GAO Yang ZHANG Xiaoxian Shiva K JHA ZHANG Hao MA Xiaojian WANG Wanning 2017Journal of Arid Land2017,9,4:12
6肾周脂肪的产热活性促进肾透明细胞癌的进展并影响肿瘤治疗效果显示文摘肾细胞癌(RCC)是一种常见的致命恶性肿瘤,占所有成人癌症的2%以上,根据组织学和细胞遗传学特征,80%的肾细胞癌被细分为透明细胞肾细胞癌(ccRCC)。肾周脂肪组织(PAT)是一种位于肾筋膜和肾包膜之间的白色脂肪组织(WAT)。在肿瘤发生过程中,ccRCC细胞可穿透肾包膜并进入PAT,与肾癌预后不良相关。然而,ccRCC和PAT之间的相互作用还没有得到很好的研究。研究者通过对ccRCC细胞和PAT之间双向通信的深入探究发现,ccRCC细胞通过旁分泌模式分泌甲状旁腺激素相关蛋白(PTHrP)激活PKA途径驱动邻近的PAT褐变,使褐色变的肾周脂肪细胞代谢增强并释放大量的代谢产物,其中过量的乳酸被释放到肿瘤微环境中,从而促进ccRCC的生长、侵袭和转移,构成了一种新的促进ccRCC肿瘤生长的可能机制。该研究提示肾癌手术中切除邻近脂肪组织可能会阻止褐色脂肪细胞的代谢产物流动,从而改善手术后的预后。杨濛(编译) 张宗勤(编译) Wei G Sun HL Dong K 2021中华医学杂志2021,101,46:6
7Neuroendocrine differentiation of prostate cancer显示文摘Zhen Li Clark J Chen Jason K Wang Elaine Hsia Wei Li Jill Squires Yin Sun Jiaoti Huang 2013Asian Journal of Andrology2013,15,3:5
8Induction of mucosal and systemic immune response by single-dose oral immunization with biodegradable microparticles containing DNA encoding HBsAg显示文摘He XW Wang F Jiang L Li J Liu SK Xiao ZY Jin XQ Zhang YN He Y Li K Guo YJ Sun SH 2005第二军医大学学报2005,26,10:5
9共用阿片类和苯二氮类药物与药物过量之间的关系:一项回顾性分析显示文摘目标确定同时使用苯二氮类药物和阿片类药物的趋势,确定这些趋势对阿片类药物过量导致的住院和急诊就诊的影响,提出修改建议。参与者:在研究期间,18~64岁的私人投保人连续参加医疗和药房福利健康计划的病人,并且至少接受过一张阿片类药物的处方。干预:同时使用苯二氮类药物/阿片类药物,定义为每种药物处方所涵盖的时间段内至少有一天重叠。主要观察结局指标:使用苯二氮类药物的阿片类药物使用者的年度百分比;每年发生的急诊就诊和阿片类药物过量住院事件。结果:阿片类药物使用者中在2001年使用苯二氮卓类药物的有9%,2013年增加到17%(相对增加80%)。这种增加主要是间断性阿片类药物使用者的增加,而非长期的阿片类药物使用者。与未使用苯二氮卓类药物的阿片类药物使用者相比,同时使用这两种药物与急诊室留观或阿片类药物过量住院相关的风险增加(校正比值比2.14,95%置信区间2.05-2.24;P<0.001)。间断性阿片类药物使用者的急诊室或住院病人阿片类药物过量的校正比值比为1.42(1.33-1.51;P<0.001),长期阿片类药物使用者为1.81(1.67-1.96;P<0.001)。如果这种关联是因果关系,那么消除同时使用两种药物的情况可以减少阿片类药物使用和阿片类药物过量住院病人因急诊就诊的风险,估计有15%(95%置信区间14-16)。结论:从2001年到2013年,在美国大量私人保险病人样本中,苯二氮类药物和阿片类药物的并用显着增加,并且导致总体人群阿片类药物过量使用的风险。Sun EC Dixit A Humphreys K 李楠琦 2018中国疼痛医学杂志2018,24,6:5
10Recent advances in nanorobotic manipulation inside scanning electron microscopes显示文摘A scanning electron microscope(SEM)provides real-time imaging with nanometer resolution and a large scanning area,which enables the development and integration of robotic nanomanipulation systems inside a vacuum chamber to realize simultaneous imaging and direct interactions with nanoscaled samples.Emerging techniques for nanorobotic manipulation during SEM imaging enable the characterization of nanomaterials and nanostructures and the prototyping/assembly of nanodevices.This paper presents a comprehensive survey of recent advances in nanorobotic manipulation,including the development of nanomanipulation platforms,tools,changeable toolboxes,sensing units,control strategies,electron beam-induced deposition approaches,automation techniques,and nanomanipulation-enabled applications and discoveries.The limitations of the existing technologies and prospects for new technologies are also discussed.Chaoyang Shi Devin K Luu Qinmin Yang Jun Liu Jun Chen Changhai Ru Shaorong Xie Jun Luo Ji Ge Yu Sun 2016Microsystems & Nanoengineering2016,2,1:4
11BK nephropathy in the native kidneys of patients with organ transplants: Clinical spectrum of BK infection显示文摘Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy(BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.Darlene Vigil Nikifor K Konstantinov Marc Barry Antonia M Harford Karen S Servilla Young Ho Kim Yijuan Sun Kavitha Ganta Antonios H Tzamaloukas 2016World Journal of Transplantation2016,6,3:4
12Seasonal variations of phytoplankton diversity in the Coleroon coastal waters,southeast coast of India显示文摘The results of an investigation carried out during June 2005 to May 2007 on physico-chemical parameters,species composition and community structure of phytoplankton including Chlorophyll a(Chl-a) at the Coleroon coastal waters(Southeast coast of India) are reported.Air and surface water temperatures(°C) varied from 25.1 to 30.1 and from 24.5 to 28.5 respectively.Salinity values varied from 6 to 28.5 and the pH ranged between 7.0 and 8.3.Variation in dissolved oxygen content was from 3.1 to 7.5 mg/dm-3 while the light extinction coefficient values(LEC) ranged between 3.1 and 10.1 cm.The ranges of inorganic nutrients(μmol/dm-3) viz.,nitrate,nitrite,phosphate and silicate were 10.1-23.4,1.2-8.9,0.2-3.1 and 55-125,respectively.The ranges of Chlorophyll a(μg/dm-3) values was 2.0-7.5.Presently,124 phytoplankton species representing different classes viz:Bacillariophyceae(77),Dinophyceae(19),Cyanophyceae(15),Chlorophyceae(10) and Chrysophyceae(3) were recorded.The phytoplankton cell abundance varied from 0.290 to 111.662 cells/cm-3,with peak diversity(3.38 bits/ind.) during summer season.The maximum abundance was found during summer season coinciding with the stable hydrographical conditions.The seasonal distribution and abundance of phytoplankton are discussed in relation to hydrographical parameters.Canonical Correspondence Analysis(CCA) was applied in this paper for discriminating environmental factors having effect on phytoplankton community at species level.Coleroon coastal water is subjected to long term fluctuations in physico-chemical parameters depending upon the seasonal tidal amplitude and freshwater influx resulting in a continuous exchange of organic,inorganic,plant and animal matters.Thillai Rajasekar K Rajkumar M SUN Jun Ashok Prabu V Perumal P 2010Acta Oceanologica Sinica2010,29,5:3
13Loss of MeCP2 in cholinergic neurons causes part of RTT- like phenotypes via α7 receptor in hippocampus显示文摘Ying Zhang Shu-Xia Cao Peng Sun Hai-Yang He Ci-Hang Yang Xiao-Juan Chen Chen-Jie Shen Xiao-Dong Wang Zhong Chen Darwin K Berg Shumin Duan Xiao-Ming Li 2016Cell Research2016,26,6:3
14Structural Characterization of Lignins Isolated from Caragana sinica Using FT-IR and NMR Spectroscopy显示文摘In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(FT-IR) and 1D and 2D Nuclear Magnetic Resonance(NMR).FT-IR spectra revealed that the 'core' of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon.XIAO Ling-ping SHI Zheng-jun XU Feng SUN Run-cang Amar K Mohanty 2011光谱学与光谱分析2011,31,9:3
15Versatile active biquad based on second-generation current conveyors显示文摘Sun Y Fidler J K 1994Int J Electronics1994,76,1:2
16Overcoming Jahn-Teller distortion for spinel Mn phase显示文摘Sun Y K Jeon Y S Lee H J 2000Electrochem SolidState Lett2000,3,:2
17Measuring the fractal dimension of signals:morphological covers and iterative optimization显示文摘Maragos P Sun F K 0,,01:2
18Fluorescence and SEM correlative microscopy for nanomanipulation of subcellular structures显示文摘Nanomanipulation under scanning electron microscopy(SEM)enables direct interactions of a tool with a sample.We recently developed a nanomanipulation technique for the extraction and identification of DNA contained within sub-nuclear locations of a single cell nucleus.In nanomanipulation of sub-cellular structures,a key step is to identify targets of interest through correlating fluorescence and SEM images.The DNA extraction task must be conducted with low accelerating voltages resulting in low imaging resolutions.This is imposed by the necessity of preserving the biochemical integrity of the sample.Such poor imaging conditions make the identification of nanometer-sized fiducial marks difficult.This paper presents an affine scale-invariant feature transform(ASIFT)based method for correlating SEM images and fluorescence microscopy images.The performance of the image correlation approach under different noise levels and imaging magnifications was quantitatively evaluated.The optimal mean absolute error(MAE)of correlation results is 68634 nm under standard conditions.Compared with manual correlation by skilled operators,the automated correlation approach demonstrates a speed that is higher by an order of magnitude.With the SEM-fluorescence image correlation approach,targeted DNA was successfully extracted via nanomanipulation under SEM conditions.Zheng Gong Brandon K Chen Jun Liu Chao Zhou Dave Anchel Xiao Li Ji Ge David P Bazett-Jones Yu Sun 2014Light(Science & Applications)2014,3,1:2
19纳米光子结构软膜紫外光固化纳米压印(英文)显示文摘紫外光固化纳米压印是实现纳米结构批量复制的一种新技术.其特点是低成本和高分辨,而且可以达到极高的套刻精度.为了得到大面积图案的均匀复制,可用聚二甲基硅氧烷(PDMS)制备透光的压印软模板.其母版图案可由高分辨率电子束曝光和反应离子刻蚀的方法在硅片基底上获得,然后用浇注的方法将图案转移到PDMS上.本实验特别发展了紫外光固化纳米压印适用于软膜压印的双层膜图型转移技术.该双层膜由廉价的光胶和聚甲基丙烯酸甲脂(PMMA)构成.对光胶层的压印可用普通的光学曝光仪实现.然后再将图案用反应离子刻蚀的方法转移到PMMA层中.为了证明方案的可行性,在两种不同材料的半导体基片上压印了三角晶格的光子晶体和准晶结构的图案,并用剥离的方法将它们转移到金属薄膜上,最后成功地进行了硅片刻蚀实验.相信这一纳米制做方法对大面积纳米光子结构和光学集成芯片的制造是普遍适用的.SHI J WANG Z M BAO K PEROZ C BELOTTI M XU L P LUO C X SUN M H ZHANG B JI H OUYANG Q CHEN Y 2006纳米技术与精密工程2006,4,3:2
20Practical method and novel mechanism for optical resolution of binol by molecular complexation with N-benzyl cinchonium Chloride显示文摘Wang Y sun J Ding K 2000Tetrahedron2000,56,:2
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