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Variability of Antarctic Intermediate Water south of Australia and its relationship with frontal waves

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Science China Earth Sciences 2016年第8期59卷 1674-1682页

作者： zhang LinLin YAN XiaoMei SUN che HU DunXin Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Ocean Circulation and Waves Chinese Academy of Sciences Laboratory for Ocean and Climate Dynamics Qingdao National Laboratory for Marine Science and Technology

A streamfunction EOF method is applied to a time series of hydrographic sections in the Southern Ocean south of Australia to study water mass variations. Results show that there are large thermohaline variations north of the Subantarctic Front (SAF) at 300–1500 dbar level, indicating upwelling and downwelling of the Antarctic Intermediate Water (AAIW) along isopycnal surfaces. Based on the latest altimeter product, Absolute Dynamic Topography, a mechanism due to frontal wave propagation is proposed to explain this phenomenon, and an index for frontal waves is defined. When the frontal wave is in positive (negative) phase, the SAF flows northeastward (southeastward) with the fresh AAIW downwelling (upwelling). Such mesoscale processes greatly enhance cross-frontal exchanges of water masses. Spectral analysis shows that frontal waves in the Southern Ocean south of Australia are dominated by a period of about 130 days with a phase speed of 4 cm/s and a wavelength of 450 km.

关键词： Antarctic Intermediate Water(AAIW) Stream-coordinates Frontalwave EOF

Development of Gesture-Changeable under-actuated Humanoid Robotic Finger

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 142-148页

作者： zhang Wenzeng che Demeng cheN Qiang DU Dong Key Laboratory for Advanced Materials Processing Technology of Ministry of Education Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Robotic fingers, which are the key parts of robot hand, are divided into two main kinds： dexterous fingers and under-actuated fingers. Although dexterous fingers are agile, they are too expensive. Under-actuated fingers can grasp objects self-adaptively, which makes them easy to control and low cost, on the contrary, under-actuated function makes fingers feel hard to grasp things agilely enough and make many gestures. For the purpose of designing a new finger which can grasp things dexterously, perform many gestures and feel easy to control and maintain, a concept called ＂gesture-changeable under-actuated＂（GCUA） function is put forward. The GCUA function combines the advantages of dexterous fingers and under-actuated fingers： a pre-bending function is embedded into the under-actuated finger. The GCUA finger can not only perform self-adaptive grasping function, but also actively bend the middle joint of the finger. On the basis of the concept, a GCUA finger with 2 joints is designed, which is realized by the coordination of screw-nut transmission mechanism, flexible drawstring constraint and pulley-belt under-actuated mechanism. Principle analyses of its grasping and the design optimization of the GCUA finger are given. An important problem of how to stably grasp an object which is easy to glide is discussed. The force analysis on gliding object in grasping process is introduced in detail. A GCUA finger with 3 joints is developed. Many experiments of grasping different objects by of the finger were carried out. The experimental results show that the GCUA finger can effectively realize functions of pre-bending and self-adaptive grasping, the grasping processes are stable. The GCUA finger excels under-actuated fingers in dexterity and gesture actions and it is easier to control and cheaper than dexterous hands, becomes the third kinds of finger.

关键词： robot technology robotic hand gesture-changeable under-actuation pre-bending self-adaptation

慢病毒介导过表达端粒酶逆转录酶的人口腔黏膜上皮稳定细胞系的构建

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华西口腔医学杂志 2016年第5期34卷 443-447页

作者：曾飒秦晓东何祥一车春晓张潇解斯羽孙贵军王立鹤兰州大学口腔医学院中国农业科学院兰州兽医研究所兰州730000

目的通过慢病毒法建立稳定表达外源性人端粒酶逆转录酶(h TERT)基因的口腔黏膜上皮细胞(OMECs),探索构建高效、稳定的永生化OMECs细胞系的方法。方法提取293T细胞总RNA,应用聚合酶链反应(PCR)法扩增h TERT基因全长,构建重组慢病毒载体p ... 详细信息

目的通过慢病毒法建立稳定表达外源性人端粒酶逆转录酶(h TERT)基因的口腔黏膜上皮细胞(OMECs),探索构建高效、稳定的永生化OMECs细胞系的方法。方法提取293T细胞总RNA,应用聚合酶链反应(PCR)法扩增h TERT基因全长,构建重组慢病毒载体p LVX-puro-h TERT。包装慢病毒颗粒后感染人正常OMECs,经嘌呤霉素抗性筛选获得阳性克隆,采用实时荧光定量PCR法和Western blot法检测h TERT基因m RNA和蛋白的表达水平。结果成功构建了p LVX-puro-h TERT过表达慢病毒载体并感染到OMECs中;感染细胞与正常OMECs形态相似,呈铺路石样生长;实时荧光定量PCR和Western blot结果均显示,h TERT在感染细胞中高表达,与正常细胞相比差异有统计学意义(P<0.05)。结论通过慢病毒法成功建立了过表达h TERT的OMECs稳定细胞系,为构建高效、稳定增殖的人永生化OMECs细胞系奠定了实验基础。

关键词：口腔黏膜上皮细胞人端粒酶逆转录酶慢病毒载体稳定表达永生化

卡铂对视网膜母细胞瘤化疗患儿听力损伤的观察

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眼科 2011年第6期20卷 404-407页

作者：崔洁马晓莉于刚吴倩金眉张诚玥赵军阳首都医科大学附属北京儿童医院眼科儿科学国家重点学科 100045 首都医科大学附属北京儿童医院血液中心儿科学国家重点学科首都医科大学附属北京同仁医院眼科

目的观察卡铂在化疗过程中对视网膜母细胞瘤患儿的听力损伤及其严重程度。设计回顾性病例系列。研究对象选择自2009年11月至2011年2月在我院进行卡铂（carboplatin）、依托泊苷（etoposide）、长春新碱（vincristine）方案化疗的视网膜... 详细信息

目的观察卡铂在化疗过程中对视网膜母细胞瘤患儿的听力损伤及其严重程度。设计回顾性病例系列。研究对象选择自2009年11月至2011年2月在我院进行卡铂（carboplatin）、依托泊苷（etoposide）、长春新碱（vincristine）方案化疗的视网膜母细胞瘤患者111例,排除相关因素后95例患者（135眼）入选。方法分别在第1、3、6次化疗前进行与年龄相匹配的听力学检查,包括纯音测听（pure-tone audiometry）检查、畸变产物耳声发射（distortion-product otoacoustic emission,DPOAE）检查、听力脑干诱发电位（auditory brainstem response,ABR）检查等。观察化疗过程中双耳听力阈值的变化情况,并判断是否有听力损害。主要指标听力阈值。结果进行化学治疗的平均疗程为5.4次（3~10次）。化疗过程中,95例患者中仅3例出现听力检查结果的异常,其中2例在随后的复查中双耳阈值恢复正常,1例在3次随访听力检查中均提示左耳阈值提高。结论卡铂对视网膜母细胞瘤化疗患者的听力损伤并不常见,程度较轻,但对患儿进行听力监测十分必要。

关键词：卡铂耳毒性视网膜母细胞瘤

高血压病人同型半胱氨酸与MTHFR 677C/T基因多态性相关性研究及不同剂量叶酸干预效果评价

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蚌埠医学院学报 2022年第3期47卷 334-336,339页

作者：董文红褚强强章车明张尧吴政治安徽省合肥市第一人民医院全科医学科 230061

目的:探讨高血压病人同型半胱氨酸(Hcy)水平与MTHFR 677C/T基因多态性的相关性,评价不同剂量叶酸治疗不同基因型高Hcy血症效果。方法:筛选高血压病人359例,进行Hcy筛查及MTHFR 677C/T基因检测,根据基因类型分为CC型、CT型和TT型,每种基... 详细信息

目的:探讨高血压病人同型半胱氨酸(Hcy)水平与MTHFR 677C/T基因多态性的相关性,评价不同剂量叶酸治疗不同基因型高Hcy血症效果。方法:筛选高血压病人359例,进行Hcy筛查及MTHFR 677C/T基因检测,根据基因类型分为CC型、CT型和TT型,每种基因类型筛选50例病人,随机分为2组,各25例,给予0.8 mg和5 mg叶酸治疗8周,评价治疗效果。结果:359例高血压病人中合并有高Hcy血症119例,发病率为55.43%。男性病人高Hcy血症发生率及血浆Hcy水平均明显高于女性(P0.05)。0.8 mg组和5 mg组不同基因类型干预后的血浆Hcy水平较干预前均明显下降(P<0.01);干预后组内不同基因型Hcy水平差异有统计学意义(P<0.01),0.8 mg组和5 mg组中CC型Hcy水平低于CT和TT型(P<0.05);0.8 mg组CT型Hcy水平低于TT型(P<0.05)。结论:Hcy水平与MTHFR 677C/T基因多态性存在相关性,叶酸能有效降低Hcy水平,大剂量叶酸与较小剂量叶酸干预效果无明显差异。基因类型不同,叶酸干预效果存在差异。

关键词：高血压同型半胱氨酸 MTHFR 677C/T基因多态性叶酸

维普期刊数据库博看期刊

Spontaneously bundled nanotubes exhibit greatly enhanced emission via inter-nanotube energy transfer

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Science China chemistry 2016年第10期59卷 1348-1351页

作者： cheng Peng Juan Yang Yifan zhang Yibin zhang Yanke che Beijing National Laboratory for Molecular Sciences Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Institute of Applied chemistry Henan Polytechnic UniversityJiaozuo 454003China

Spontaneously bundled nanotubes assembled from chiral perylene diimide molecules exhibit greatly enhanced emission via inter-nanotube excitation energy transfer. The formation of densely packed superstructures is an effective approach for high fluorescence quantum yield in assembled nanomaterials without compromising optoelectronic properties.

关键词： nanotube fluorescence quantum yield inter-tube energy transfer

葛根素对5种细胞色素P_(450)酶体外活性影响研究

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医药导报 2007年第8期26卷 852-856页

作者：涂自良张澈程晓莉王启斌张蓬华郧阳医学院附属太和医院药学部郧阳医学院药学系湖北十堰442000

目的研究葛根素体外对细胞色素P450酶亚型CYP1A2、CYP2C9、CYP2C19、CYP2D6和CYP3A4等活性的影响。方法分别以咖啡因、甲苯磺丁脲、美芬妥因、美托洛尔和咪哒唑仑为探针药,采用高效液相色谱法测定探针药与相应代谢产物的浓度,采用重组... 详细信息

目的研究葛根素体外对细胞色素P450酶亚型CYP1A2、CYP2C9、CYP2C19、CYP2D6和CYP3A4等活性的影响。方法分别以咖啡因、甲苯磺丁脲、美芬妥因、美托洛尔和咪哒唑仑为探针药,采用高效液相色谱法测定探针药与相应代谢产物的浓度,采用重组酶研究葛根素对CYP1A2、CYP2C9、CYP2C19、CYP2D6和CYP3A4酶体外活性的影响。结果在体外重组酶反应体系中,葛根素对CYP2C9、CYP2C19及CYP3A4酶活性无明显影响。但低浓度(0.1mmol.L-1)下可使CYP1A2活性降低(48±9)%(P<0.05),使CYP2D6活性降低(61±8)%(P<0.01);高浓度(0.4mmol.L-1)下使CYP1A2活性降低(82±8)%(P<0.01),使CYP2D6活性降低(88±6)%(P<0.01)。结论葛根素对CYP1A2和CYP2D6酶体外活性有较明显的抑制作用;随着葛根素浓度的增高,抑制作用也相应增强。

关键词：葛根素重组酶细胞色素P450酶

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核磁共振技术在生命科学中的应用

生命科学仪器 2003年第1期1卷 6-9页

作者：车文华张一鸣中国科学院电工研究所北京100080

在过去的50年中,核磁共振技术已经成为应用广泛的一种分析测量工具。由于具有无侵入、无破坏和测量信息丰富等诸多优点,核磁共振技术对于生命科学的研究工作者极具吸引力。本文对核磁共振技术在生命科学中的主要应用进行了归纳总结。由... 详细信息

在过去的50年中,核磁共振技术已经成为应用广泛的一种分析测量工具。由于具有无侵入、无破坏和测量信息丰富等诸多优点,核磁共振技术对于生命科学的研究工作者极具吸引力。本文对核磁共振技术在生命科学中的主要应用进行了归纳总结。由此不难看出核磁共振技术已经渗透到生命科学领域的多个学科分支显示出了良好的应用前景。

关键词：核磁共振生命科学 NMR

Ultralow oxygen ion diffusivity in pyrochlore-type La_(2)(Zr_(0.7)Ce_(0.3))_(2)O_(7)

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Journal of Materials Science & Technology 2022年第7期102卷 174-185页

作者： Junwei che Xiangyang Liu Xuezhi Wang Quan zhang Erhu zhang Gongying Liang Shengli zhang MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Applied Physics School of ScienceChang’an UniversityXi’an 710064China

Thermally grown oxides(TGOs)at the ceramic top-coat/metallic bond-coat interface are a pressing chal-lenge in advanced thermal barrier coating(TBC)systems as they can affect the performance and ser-vice lifetime of ***,developing novel TBC materials with ultralow oxygen ion diffusivity is very *** this study,we reported the diffusive properties of oxygen ions in a novel pyrochlore-type La_(2)(Zr_(0.7)Ce_(0.3))_(2)O_(7)(LZ7C3)*** measured ionic conductivity and atomistic simulation revealed that the oxygen ion diffusivity in LZ7C3 grains is two orders of magnitude lower than that in conventional 8 wt.%yttria-stabilized zirconia(8YSZ)*** is due to the relatively high energy barrier for oxygen hopping in *** addition,it was found that enhancing the order distribution of cations is a strategy to reduce the intrinsic oxygen diffusion of pyrochlore-type *** the other hand,we observed that La^(3+) cations segregate at the grain boundaries(GBs)of LZ7C3,which results in the electrostatic poten-tial at GBs being comparable to that in the ***,we found that the oxygen ion diffusion is facilitated at the GBs of LZ7C3 due to the stretched O-Zr/Ce bond and the low coordination at ***-ever,the segregations of Y^(3+)cations and the increase in the number of oxygen vacancies resulted in the formation of an electrostatic layer at the GBs of 8YSZ,which shielded the oxygen ion *** this,the oxygen ion diffusivity in LZ7C3 was still considerably less than that in conventional *** study offers a stepping stone toward utilizing pyrochlore-type LZ7C3 materials as advanced TBCs at high temperatures.

关键词： Oxygen ion diffusion La_(2)(Zr_(0.7)Ce_(0.3))_(2)O_(7) Pyrochlore structure Thermal barrier coatings