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英格兰东北部17型脊髓小脑性共济失调的最低患病率

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世界核心医学期刊文摘（神经病学分册） 2006年第3期2卷 25-25页

作者： Craig K. Keers S.M. walls T.J. P.f. Chinnery 王孝文 Neurology Medical School Framlington Place Newcastle upon Tyne NE2 4HH United Kingdom

Objective: To determine the minimum prevalence of spinocerebellar ataxia type 17 (SCA17) in the north east of England. Patients and methods: A defined region containing 2,516,500 individuals with 192 families with undiagnosed ataxia, 90 patients with a Huntington’s disease-like phenotype and 292 controls. The number of (CAG/CAA)n repeats in the SCA17/TBP gene was determined by fluorescent PCR and sequenced in affected individuals. Results: The mean repeat size for 584 control alleles was 34 (S.D. = 3.58), ranging from 25 to 40. Two index cases had larger alleles with repeat lengths greater than the control range. Affected family members presented in adult life with ataxia followed by extrapyramidal features and cognitive impairment. In one family 44 repeats were associated with a younger age of onset than has been previously described. Conclusions: The minimum prevalence of SCA17 in the north east of England was 0.16/100,000 (upper 95%confidence interval 0.31/100,000).

关键词：共济失调亨廷顿病认知功能损害重复次数锥体外系

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用温压制造高密度材料的关键参数

粉末冶金工业 2012年第1期22卷 1-8页

作者： S.St-Laurent f.Chagnon 韩凤麟 Quebec Metal Powder Limited

温压技术是由在加热的阴模中压制预热的粉末组成[1],已知温压有助于零件密实,从而改进烧结件的性能[2,3]。温压需要在适合温压的温度范围内进行。特别是,粉末混合粉应具有好的流动性,同时对阴模模壁有良好润滑性,以减小脱模力。在试验... 详细信息

温压技术是由在加热的阴模中压制预热的粉末组成[1],已知温压有助于零件密实,从而改进烧结件的性能[2,3]。温压需要在适合温压的温度范围内进行。特别是,粉末混合粉应具有好的流动性,同时对阴模模壁有良好润滑性,以减小脱模力。在试验室和工业生产中都研究了用粘结剂处理的和未经粘剂处理的用温压技术制造的材料的性状与性能。为了确定和定量各种关键生产参数,诸如压制压力,粉末温度与阴模温度,生产速率及零件大小对生坯和烧结件特性和零件脱模力的影响,进行了专门的试验研究。依照粉末流动性与松装密度的稳定性,压制压力与温度以及压制零件的重量与密度讨论了温压的工艺性。

关键词：温压高密度材料关键参数

Acoustical Design of an Electrical Emergency Plant Using Sea Method

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Journal of Environmental Protection 2014年第4期5卷 327-332页

作者： Evgeny Podzharov José f. de la Mora Gálvez Jesus A. Alvarez Sanchez Electromechanical Engineering Department University of Guadalajara Puerta 10 Guadalajara México Superior School of Engineering Prolongacion Calz University of Panamericana Circunv. Pte 49 Guadalajara México

The statistical energy analysis (SEA) was used in the acoustical design of an electrical emergency plant to reduce the outdoor noise level. In the past, when the plant was working, a high annoying noise was heard all over the university camp. At a first glance the principal ways of noise propagation were the open door of the plant which was used for the suction of fresh air and a vast hole in the ceiling which was used for gases outlet. Also, a spectral analysis of the noise inside the plant showed that the dominant frequencies of the noise were in the range of 120 - 270 Hz. This frequency range is near the critical frequency of the brick walls that is 129 Hz, at which the walls are transparent for noise. A two-block diagram is used for the statistical energy analysis. Two ways of sound transmission are considered through the inlet and outlet holes and through the walls and ceiling. This analysis shows that the exclusion of holes wouldn’t be sufficient to reduce noise to an acceptable level in a low frequency range but increase the noise absorption by the wall coating material. The transmission loss is calculated for different wall coatings and hole areas. A layer of fiberglass of two-inch width is selected to increase the wall absorption coefficient. Special silencers are designed and put at the suction of air and at the outlet of engine gases to reduce the noise propagation through the holes. The noise measurement shows that the noise level is considerably reduced after implementation of these measures. The reduction of noise is 7 - 8 dB (A), 19 dB (A) and 23 dB (A), inside the plant, 10 m and 15 m away from the plant, respectively.

关键词： Noise Reduction of an Elictric Plant Statistical Energy Analysis Transmission Loss Spectral Analysis Absoption of Noise

MAGNETIZATION BEHAVIOR IN SINTERED Nd-fe-B MAGNETS

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Journal of Rare Earths 1990年第1期8卷 37-42页

作者： Li Dong(Central Iron & Steel Research Institute,Beijing 100081,P.R.China)K.J.Strnat H.f.Mildrum(University of Dayton,USA)

Magnetization and demagnetization curves and hysteresis loops applied different *** in sintered Nd-fe-B and Nd-Dy-fe-B magnets from thermally demagnetized and dc field-demagnetized states were investigated at temperatures of up to 150℃.The first-quadrant remagnetization curves and the curves of coercive forces _MH_C versus rernagnetizing fietds H_m from dc field-demagnetized state at room temperature show a step around magnetizing field as absolute value of the maximum intrinsic *** steps of _MH_C-H_m curves shifted to lower remagnetizing fields and the shapes of magnetization curves changed from step type to precipitous type when temperature went up to 100～150℃ or after the specimen was thermally demagnetized at a temperature higher than the Curie *** steep rise of knee coereivity with increasing magnetizing field is behind that of _MH_*** that the magnetic hardening in sintered Nd-fe-B magnets is controlled by pinning of domain walls.

关键词： Dy fe MAGNETIZATION BEHAVIOR IN SINTERED Nd-fe-B MAGNETS Nd

The miR319-Targeted GhTCP4 Promotes the Transition from Cell Elongation to Wall Thickening in Cotton fiber

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Molecular Plant 2020年第7期13卷 1063-1077页

作者： Jun-feng Cao Bo Zhao Chao-Chen Huang Zhi-Wen Chen Ting Zhao Hong-Ru Liu Guan-Jing Hu Xiao-Xia Shangguan Chun-Min Shan- Ling-Jian Wang Tian-Zhen Zhang Jonathan f.Wendel Xue-Ying Guan Xiao-Ya Chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China Plant Stress Biology Center Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Shanghai 200032China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Agronomy Department College of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiang 310058China Department of Ecology Evolution and Organismal BiologyIowa State UniversityAmesIA 50011.USA Plant Science Research Center Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai 201602China

Plant cell growth involves a complex interplay among cell-wall expansion, biosynthesis, and, in specific tissues, secondary cell wall (SCW) deposition, yet the coordination of these processes remains elusive. Cotton fiber cells are developmentally synchronous, highly elongated, and contain nearly pure cellulose when mature. Here, we report that the transcription factor GhTCP4 plays an important role in balancing cotton fiber cell elongation and wall synthesis. During fiber development the expression of miR319 declines while GhTCP4 transcript levels increase, with high levels of the latter promoting SCW deposition. GhTCP4 interacts with a homeobox-containing factor, GhHOX3, and repressing its transcriptional activity. GhTCP4 and GhHOX3 function antagonistically to regulate cell elongation, thereby establishing temporal control of fiber cell transition to the SCW stage. We found that overexpression of GhTCP4A upregulated and accelerated activation of the SCW biosynthetic pathway in fiber cells, as revealed by transcriptome and promoter activity analyses, resulting in shorter fibers with varied lengths and thicker walls. In contrast, GhTCP4 downregulation led to slightly longer fibers and thinner cell walls. The GhHOX3–GhTCP4 complex may represent a general mechanism of cellular development in plants since both are conserved factors in many species, thus providing us a potential molecular tool for the design of fiber traits.

关键词： cell elongation secondary cell wall cotton fiber Gossypium hirsutum TCP microRNA

Titania coating formation on hydrostatically extruded pure titanium by micro-arc oxidation method

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Journal of Materials Science & Technology 2022年第16期111卷 224-235页

作者： Ł.Maj D.Wojtas A.Jarz˛ebska M.Bieda K.Trembecka-Wójciga R.Chulist W.Kozioł A.Góral A.Trelka K.Janus J.Kawałko M.Kulczyk f.Muhaffel H.Çimeno˘glu K.Sztwiertnia Institute of Metallurgy and Materials Science Polish Academy of SciencesReymonta 25Krakow 30-059Poland faculty of Physics and Applied Computer Science AGH University of Science and TechnologyKrakowPoland Academic Centre of Materials and Nanotechnology AGH University of Science and TechnologyKrakowPoland Institute of High Pressure Physics Polish Academy of SciencesWarsawPoland Department of Metallurgical and Materials Engineering Istanbul Technical UniversityIstanbulTurkey

In this work,the microstructure of titania coating fabricated on the surface of hydrostatically extruded titanium grade 4 with the use of the micro-arc oxidation method was *** surface topography and microstructure investigations performed with atomic force microscopy and scanning and transmission electron microscopy revealed that,by using an Na_(2)HPO_(4)electrolyte,a well-adherent porous coating is produced on the top surface and side walls of the extruded *** distribution of chemical elements was analyzed by using energy dispersive X-ray *** chemical elements dissolved in the electrolyte(Na,P and O)incorporated into the *** locates preferentially in the outer part of the coating,while phosphorus and oxygen are distributed throughout the whole *** most relevant finding shows that a grain refinement caused by a hydrostatic extrusion provoked an increase in density of high-angle grain boundaries(HAGB),which in turn secured the formation of a continuous amorphous layer close to the *** presence of this layer compensates for the effect of anisotropic substrate,producing a comparable and homogenous microstructure with a large number of micropores.

关键词： Micro-arc oxidation Titanium of commercial purity Hydrostatic extrusion Surface topography Microstructure

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抗震工程中的钢和混凝土组合结构体系分析

钢结构 2008年第2期23卷 82-83页

作者： Jerome f. Hajjar

过去10年里,美国国内关于钢和混凝土组合体系建筑抗震工程的研究有显著的增多。对最近一系列组合横向阻力系统的研究进行了概述,包括由钢梁和混凝土填充的钢管组成的无支撑框架,带有混凝土填充钢管柱的支撑框架,型钢混凝土柱以及一系列... 详细信息

过去10年里,美国国内关于钢和混凝土组合体系建筑抗震工程的研究有显著的增多。对最近一系列组合横向阻力系统的研究进行了概述,包括由钢梁和混凝土填充的钢管组成的无支撑框架,带有混凝土填充钢管柱的支撑框架,型钢混凝土柱以及一系列变化的组合混杂墙系统。相对于很多一般的系统,这些结构体系的优点包括它们在承受正常使用或极限荷载时的性能特征,以及材料与结构的经济性。此外,介绍其中一种混合系统深入研究的成果,包括部分约束的带有加强混凝土填充墙的钢框架。总结出这些组合体系将来设计条款的概要。

关键词：梁和柱梁柱节点 CfT 组合结构组合墙系统混凝土填充钢管 HWS 混杂墙体系抗震工程 SRC

Some recent permanent geosynthetic - reinforced soil structures in Japan

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Some recent permanent geosynthetic - reinforced soil structu...

中国土木工程学会第九届土力学及岩土工程学术会议

作者： f.Tatsuoka M.Tateyama T.Uchimura J.Koseki Departrnent of Civil Engineering University of Tokyo Railway Technical Research Institute of Japan Railways Group Department of Civil Engineering University of Tokyo Institute of Industrial Science University of Tokyo

＜正＞ A number of geosynthetic - reinforced soil （GRS） retaining walls with a full- height rigid facing constructed by the stage construction have been constructed for railways and highways in Japan for the last 15 years. The construction and long- term behaviour of a prototype GRS bridge abutment and a preloaded and prestressed GRS bridge pier, both directly supporting railway bridge girders, is described. Results from a comprehensive series of model loading tests performed to develop these technologies as well as field full - scale loading tests are reported.

关键词： bridge abutment and pier cement - mixed soil field full - scale behaviour, geotextile - reinforced model tests preloading and prestressing soil retaining wall

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无表面波损耗的孔耦合贴片天线的设计

电波科学学报 2002年第6期17卷 565-568页

作者：程崇虎 K.Li K.f.Tong T.Matsui 南京邮电学院通信工程系江苏南京210003 CommunicationsResearchLaboratory

设计了一种新结构的孔耦合贴片天线 ,该天线结构将贴片连同制作贴片的介质基板一起放置在一个矩形金属框里 ,彻底阻断了表面波的传输。该天线结构的尺寸比一般贴片天线要小很多 ,但却具有更高的增益。还介绍了对该天线结构的数值模拟、... 详细信息

设计了一种新结构的孔耦合贴片天线 ,该天线结构将贴片连同制作贴片的介质基板一起放置在一个矩形金属框里 ,彻底阻断了表面波的传输。该天线结构的尺寸比一般贴片天线要小很多 ,但却具有更高的增益。还介绍了对该天线结构的数值模拟、样品制作和实验测量。测量数据显示矩形金属框使天线的增益在 9GHz到11GHz的频率范围内平均提高了 0 .7dB ,该天线的工作频带超过了 2 0 % ,带内平均增益为 8.3dBi ,同时天线具有良好的辐射方向图。

关键词：孔耦合贴片天线天线效率天线增益表面波损耗天线结构