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大棕蝠下丘听神经元频率调谐的方向敏感性

生物物理学报 2000年第1期16卷 81-88页

作者：张季平 Jen p.h.-s. 孙心德华东师范大学生物学系脑功能研究室上海200062 University of Missouri-Columbia

实验在8只大棕蝠(Eptesicusfuscus)上进行。选取了5个声源方位 :记录部位对侧80°(C -80°)、40°(C -40°)、0°和同侧40°(I -40°)、80°(I -80°)。下丘听神经元的频率调谐曲线的形状有三种 :V型、封闭型和U型。以C -40°的频率调... 详细信息

实验在8只大棕蝠(Eptesicusfuscus)上进行。选取了5个声源方位 :记录部位对侧80°(C -80°)、40°(C -40°)、0°和同侧40°(I -40°)、80°(I -80°)。下丘听神经元的频率调谐曲线的形状有三种 :V型、封闭型和U型。以C -40°的频率调谐曲线为对照 ,声源方位改变时 ,多数神经元频率调谐曲线的形状和最佳频率不变。多数神经元在声源方位由记录部位对侧转向同侧时 ,频率调谐曲线的锐度 (以QndB 值为指标 )由小变大 ;神经元在I -80°、I -40°的QndB 值显著高于C -80°、C -40°、0°的QndB 值。在所观察的47个神经元中 ,5个声源方位的最低阈值的平均值有显著差异 ,由高到低的分布为 :MTI -80°>MTI -40°>MT0°>MTC -80°>MTC -40°。我们推测 ,声源方位对神经元频率调谐特性影响的机制,可能是抑制性和兴奋性输入的比例不同而相互整合的结果。

关键词：频率调谐声源方位方向敏感性听神经元蝙蝠

stopping and storing light pulses within a fiber optic ring resonator

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Chinese Optics Letters 2009年第9期7卷 778-780页

作者： F.h.suhailin J.Ali p.p.Yupapin Y.Fujii h.Ahmad s.w.harun Institute of Advanced photonics sciences Science FacultyUniversiti Teknologi Malaysia Advanced Research Center for photonics Faculty of ScienceKing Mongkut's Institute of Technology Ladkrabang Department of Electronic Engineering Gunma University photonics Research Centre University of Malaya

A simple all optical system for stopping and storing light pulses is demonstrated. The system consists of an erbium-doped fiber amplifier （EDFA）, a semiconductor optical amplifier （sOA）, and a fiber ring resonator. The results show that the multisoliton generation with a free spectrum range of 2.4 nm and a pulse spectral width of 0.96 nm is achieved. The memory time of 15 min and the maximum soliton output power of 5.94 dBm are noted, respectively. This means that light pulses can be trapped, i.e., stopped optically within the fiber ring resonator.

关键词： ring In stopping and storing light pulses within a fiber optic ring resonator EDFA

Constitutive modeling of flow behavior of precipitation-hardened AA7022-T6 aluminum alloy at elevated temperature

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Transactions of Nonferrous Metals society of China 2020年第11期30卷 2927-2940页

作者： h.R.REZAEI AshTIANI p.shAhsAVARI school of Mechanical Engineering Arak University of TechnologyArakIran

The thermomechanical behavior of precipitation-hardened aluminum alloy AA7022-T6 was studied using isothermal compression at temperatures of 623−773 K and strain rates of 0.01−1 s^−*** experimental results indicated that dynamic recrystallization(DRX)is a predominant hot deformation mechanism,especially at elevated temperatures and low strain *** modified Johnson−Cook(J−C)and the strain compensated Arrhenius-type models were developed to predict the hot flow behavior under different deformation *** correlation coefficients of modified J−C model and the strain compensated Arrhenius-type models were 0.9914 and 0.9972,respectively,their average relative errors(ARE)were 6.074%and 4.465%,respectively,and their root mean square errors(RMsE)were 10.611 and 1.665 Mpa,respectively,indicating that the strain compensated Arrhenius-type model can predict the hot flow stress of AA7022-T6 aluminum alloy with an appropriate accuracy.

关键词： flow behavior constitutive models Arrhenius model dynamic recrystallization AA7022-T6 aluminum alloy

减小一独立压力控制型无级变速器压力波动的研究

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传动技术 2009年第2期23卷 42-48页

作者： p Kim w-s R yu h Kim s-h hwang h sKim 刘青（译） Application Technology Research Team Hyundai Mobis Giheung-gu Yongin-si Republic of Korea performance Test Team Hyundai Powertech Hwaseong-si Republic of Korea Automatic Transmission Design Team Hyundai Motor Company Hwaseong-si Republic o{ Korea school of Mechanical Engineering Sungkyunkwan University Suwon Republic of Korea 不详

本文研究一金属带型独立压力控制无级变速器（CVT）的压力特性，并建议修正降低稳态的压力波动。根据试验，监测辅助压力区在减速比内压力波动。为分析压力特性，求得包含CVT变速器液压控制模型，采用该动力学模型，研究影响压力波动的... 详细信息

本文研究一金属带型独立压力控制无级变速器（CVT）的压力特性，并建议修正降低稳态的压力波动。根据试验，监测辅助压力区在减速比内压力波动。为分析压力特性，求得包含CVT变速器液压控制模型，采用该动力学模型，研究影响压力波动的诸参数。根据仿真，我们发现液体刚度的变化是压力波动的主要原因。基于对刚度的分析，建议修正辅助控制阀供给部分刻痕来减少由辅助控制阀到CVT变速器液体供给管道刚度梯度。根据仿真和试验，采有这种液体刚度修正可以降低压力波动影响。

关键词：无级变速器压力波动单独控制

人NK/T细胞淋巴瘤吉西他滨耐药细胞株的建立和差异基因表达检测

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人NK/T细胞淋巴瘤吉西他滨耐药细胞株的建立和差异基因表达检测

作者：陈新峰郑州大学

学位级别：硕士

背景恶性淋巴瘤(Malignant Lymphoma, ML)是起源于人类免疫系统细胞及其前体细胞的恶性增生性疾病。根据临床病理类型可以分为霍奇金淋巴瘤(hodgkin's lymphoma, hL)和非霍奇金淋巴瘤(non-hodgkin's lymphoma, NhL)。在恶性肿瘤中,我国M... 详细信息

背景恶性淋巴瘤(Malignant Lymphoma, ML)是起源于人类免疫系统细胞及其前体细胞的恶性增生性疾病。根据临床病理类型可以分为霍奇金淋巴瘤(hodgkin's lymphoma, hL)和非霍奇金淋巴瘤(non-hodgkin's lymphoma, NhL)。在恶性肿瘤中,我国ML发病率呈逐年上升趋势,非霍奇金淋巴瘤是目前发病率增长最快的肿瘤,其发病率居全世界第五(女性)或第六(男性)位。已成为严重威胁着人类健康和生命的一种疾病。在中国从2000年1月到2008年12月6382例淋巴瘤患者被收集,其中成熟B细胞型占56%,成熟T细胞型和NK细胞型占26%,前驱恶性淋巴瘤和霍奇金淋巴瘤约占5%-13%。排前六的淋巴瘤中NK/T细胞淋巴瘤仅次于弥漫大B细胞淋巴瘤位于第二,同世界其他地区相比,亚洲尤其是中国发病率高,同其他报道相似。NK/T细胞淋巴瘤(Natural Killer/T cell lymphoma)是非霍奇金淋巴瘤的一个亚型,发病率居T细胞淋巴瘤的首位,中国发病率远高于西方国家。该病具有起病隐匿、早期诊断困难、高度侵袭性、进展速度快、生存期短、预后较差等特点,早期采用放化疗,中晚期主要是采用化疗为主的综合治疗。目前国际上对于NK/T细胞淋巴瘤尚无标准的治疗方案,因此寻找高效低毒且不易产生耐药的化疗药物势在必行。大量的临床研究证明,以吉西他滨为主的化疗方案对非霍奇金淋巴瘤的疗效确切。同时我们的前期研究通过常规化疗药物敏感试验发现NK/T淋巴瘤细胞株sNK-6、YTs对吉西他滨高度敏感,吉西他滨有可能成为有效治疗NK/T细胞淋巴瘤的药物,但NK/T细胞淋巴瘤细胞对化疗药物多药耐药是影响化疗疗效的主要因素,NK/T细胞淋巴瘤患者原发或继发耐药一直困扰着临床医生,于是本课题选择采用体外药物浓度梯度递增法建立NK/T细胞淋巴瘤吉西他滨耐药细胞株YTs-Gem,为进一步研究NK/T细胞淋巴瘤的发生发展和耐药产生机制提供了理想的模型,同时本课题发现的基因表达差异,为NK/T细胞淋巴瘤的基础和临床研究提供了重要的研究线索。目的建立人NK/T细胞淋巴瘤细胞株(YTs)吉西他滨(Gemcitabine, Gem)耐药细胞株(YTs-Gem),研究其生物学特性,检测YTs和YTs-Gem的基因表达差异,探讨NK/T细胞淋巴瘤耐药机制。方法应用体外细胞培养技术对YTs细胞进行体外培养,采用吉西他滨体外浓度梯度递增法建立可以稳定传代的YTs-Gem.光镜观察形态学变化、MTT法分析耐药指数、绘制生长曲线、计算倍增时间以及流式细胞仪分析YTs、YTs-Gem的细胞周期分布及表面标记物;采用荧光实时定量pCR (Real-time pCR)检测细胞周期相关基因Caspase,细胞凋亡相关基因p53、肿瘤坏死因子相关的凋亡诱导配体基因(TRAIL)和髓样细胞白血病-1基因(Mcl-1),合成、修复和重组相关基因核糖核苷酸还原酶亚单位M1和M2(RRM1和RRM2),细胞代谢相关基因脱氧胞苷激酶(dCK)和脱氧胞苷脱氨酶dCDA,耐药相关基因多药耐药基因1(mdr-1)、肺耐药基因(LRp)和多药耐药相关基因(MRp),比较上述基因在YTs和YTs-Gem内基因表达差异。结果1成功建立了人NK/T细胞淋巴瘤耐药细胞株YTs-Gem, YTs-Gem与YTs同源。2与YTs相比,具有不同的生物学特性：YTs和YTs-Gem对吉西他滨的IC50值分别为0.049μg/mL和1.960μg/mL,耐药指数达到了40;与YTs相比生长速度变慢,倍增时间分别为41.36h和51.17h;与YTs相比,YTs-GemGO/G1期细胞比例减少、s期细胞比例增多、G2/M期细胞无明显变化,组间比较差异有统计学意义(ppCR检测结果显示：Mcl-1、p53、MRp、dCDA、RRM1及RRM2在YTs-Gem的表达明显升高(pspase、TRAIL在YTs-Gem的表达明显降低(pp在YTs及YTs-Gem中表达无明显差异(p>0.05)结论1成功建立了人NK/T细胞淋巴瘤耐药细胞株YTs-Gem。2YTs-Gem具有不同于正常NK/T细胞淋巴瘤细胞株YTs的生物学特征,两者之间有广泛的差异表达基因,包括细胞周期相关基因、细胞凋亡相关基因、合成和修复相关基因、细胞代谢相关基因以及耐药相关基因。

关键词：人NK/T细胞淋巴瘤耐药细胞株基因表达吉西他滨

Experimental investigation on damage evolution behaviour of a granitic rock under loading and unloading

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Journal of Central south University 2018年第5期25卷 1213-1225页

作者：戴兵赵国彦 h.KONIETZKY p.L.p.wAsANThA Nuclear Resources Engineering College University of South ChinaHengyang 421001China school of Resources and safety Engineering Central South UniversityChangsha 410001China Geotechnical Institute TU BergakademieFreiberg 09599Germany

In-situ rock failures can result from stress changes due to pure loading and/or unloading. Understanding of the damage evolution behavior in brittle rocks during loading and unloading is imperative for the designs of rock structures. In this paper, we investigate the damage evolution characteristics of a granitic rock during loading and unloading after a series of triaxial experiments performed at different confining pressures. The axial stress-axial strain variations of the tested specimens revealed that the specimens undergoing unloading fail with a lower axial strain compared to the specimens failed purely by loading. higher confining pressures were observed to exacerbate the difference. Volumetric strain versus axial strain curves indicated that the curves reverse the trend with the beginning of major damage of specimens. we suggest here a new form of equation to describe the secant modulus variation of brittle rocks against the axial stress for the unloading process. Failure mechanisms of tested specimens showed two distinct patterns, namely, specimens under pure loading failed with a single distinct shear fracture while for the unloading case specimens displayed multiple intersecting fractures. In addition, analysis of the evolution of dissipation and elastic energy during deformation of the specimens under loading and unloading conditions showed differentiable characteristics. Moreover, we evaluated the variations of two damage indices defined based on the energy dissipation and secant modulus evolution during deformation and observed that both of them satisfactorily distinguish key stages of damage evolution.

关键词： damage evolution loading and unloading granitic rock triaxial testing

Transthoracic En-bloc Esophagectomy

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The Chinese-German Journal of Clinical Oncology 2004年第4期3卷 229-232页

作者： w. schrder p. M. schneider A. h. hlscher Department of Visceral- and Vascular surgery University of CologneDepartment of Visceral- and Vascular surgery University of CologneDepartment of Visceral- and Vascular surgery University of Cologne Cologne GermanyCologne GermanyCologne Germany

In patients with esophageal carcinoma surgical resection remains the standard of curative treatment. For locally advanced tumors (pT1sm–pT3) transthoracic esophagectomy with extended lym- phadenectomy is the standard surgical procedure since it o?ers a complete removal of the primary tumor and possible lymph node metastases. This surgical resection is appropriate for squamous cell but also adenocarcinoma of the esophagus because both histological entities demonstrate a lymphatic spread to the abdominal compartment and the upper mediastinum. In-hospital mortality rates are between 6% and 9%; anastomotic leakage and pulmonary complications mainly contribute to postoperative morbidity. In terms of 5-year survival the transthoracic procedure o?ers a better prognosis compared to the transhiatal resection. 五笔字型计算机汉字输入技术

关键词： transthoracic esophagectomy

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大棕蝠听皮层对下丘听神经元频率调谐的调制

科学通报 2000年第24期45卷 2636-2641页

作者：张季平孙心德 p. h. s. Jen 华东师范大学生物学系脑功能研究室 Division of Biological sciences University of Missouri-ColumbiaMO 65211 USA

用双声刺激的方法和电刺激技术, 进一步研究了在激活听皮层前后下丘听神经元兴奋性和抑制性频率调谐曲线的锐度、频率强度反应区域、最低阈值的协同变化. 结果表明, 听皮层的抑制性影响使下丘听神经元兴奋性频率调谐曲线的锐度增加、最... 详细信息

用双声刺激的方法和电刺激技术, 进一步研究了在激活听皮层前后下丘听神经元兴奋性和抑制性频率调谐曲线的锐度、频率强度反应区域、最低阈值的协同变化. 结果表明, 听皮层的抑制性影响使下丘听神经元兴奋性频率调谐曲线的锐度增加、最低阈值升高、频率强度反应区域减小, 同时使抑制性频率调谐曲线的锐度减小、最低阈值下降、频率强度反应区域增大. 听皮层的易化性影响与之相反. 在听皮层的抑制性影响中, 兴奋性与抑制性频率调谐曲线的频率强度反应区域变化的百分数呈显著负相关. 结果提示, 听皮层可能通过调制下丘听神经元的抑制性频率调谐曲线来提高下丘听神经元对频率信息的处理能力.

关键词：蝙蝠听皮层下丘频率调谐调制听神经元听觉

self healing Asphalt Concrete-state of the Art

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武汉理工大学学报 2010年第17期32卷 67-70,88页

作者： JIANG h wU s p QIU J wEI w Key Laboratory of silicate Materials science and Engineering Wuhan University of TechnologyWuhan 430070China Delft University of Technology P.O. Box 50482600 GA Delftthe Netherlands

similar to engineering materials used in civil engineering,aerospace engineering and other applications,an asphalt concrete also suffers from fatigue cracking due to a cyclic loading conditions on the road,which results in a decrease of the stiffness and the strength. The self healing capability has been investigated widely due to its unique contribution to the recovery of the stiffness and the strength from cracking and then to extend the service life of asphalt pavements. In this paper,general concepts of self healing and self healing asphalt concrete were introduced. Then,the parameters that influence the self healing capability of the asphalt binder and asphalt concrete were discussed. Inspired from other self healing materials,the possibilities of applying microcapsule self healing system in asphalt concrete were investigated in detail.

关键词： self-healing asphalt asphalt concrete microcapsules