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北疆地区全新世气候波动与水热组合特点

中国沙漠 , 2000,
Abstract: 湖沼沉积、黄土沉积和冰积等地质记录的研究表明,北疆地区全新世气候受地理位置和大气环流影响,气候变化较为复杂。整个北疆地区早全新世气候暖干,中全新世至现代,气候特点因地因时而异。受西风控制地区,代表暖干环境的黄土沉积可一直延伸到晚全新世,而可能受夏季风影响的地区和偏北的阿尔泰山,环境的好转早于西风区,并且气候的波动也较西风区更为频繁。
信息化时代的高等教育改革

科技进步与对策 , 2002,
Abstract: 就信息化时代高等教育的社会基础变化以及由此带来的高等教育改革进行初步分析。教育改革信息化时代高等教育影响网络教学
城市流动人口增多的原因、利弊和对策

人口研究 , 1988,
Abstract: ?<正>《人口与发展》1987年第2期发表鲜开值的文章,认为近几年城市流动人口出现了增长速度加快,务工经商、联系业务人员明显增多,自然构成大大高于城市常住人口,留住时间长等一些新特点。
细菌细胞分裂中能量转化机制研究
发表于《Science》2013年6144期,引自
http://www.sciencemag.org/content/341/6144/392.abstract  [PDF]


QianRen Biology (QRB) , 2014, DOI: 10.12677/QRB.2014.11003
Abstract: 细菌细胞以二分裂的方式在细胞中部进行对称分裂,细胞骨架蛋白FtsZ是最早出现在分裂位点的蛋白,在细胞分裂过程中起着重要的作用。FtsZ蛋白能够通过首尾相接形成原丝纤维,继而自组装成细菌细胞分裂过程中的一个关键细胞器-Z环。细胞分裂时,Z环定位在细胞中部的分裂位点处并且紧贴细胞膜内侧,随着隔膜的形成,Z环通过将水解GTP释放的化学能转化成向内拉伸的机械能,逐渐收缩自身直径并且带动隔膜内陷,直到分裂完成。在对FtsZ进行研究的几十年中,由于科学家们一直未能得到FtsZ原丝纤维的三维结构,所以Z环是怎样利用GTP水解释放的化学能为细菌细胞分裂提供收缩动力的,这个问题始终没有得到解答。叶升课题组解析了结核分枝杆菌的FtsZ原丝纤维的结构,通过将解析得到的结核分枝杆菌FtsZ与GDP形成的原丝纤维结构与之前报导过的金黄色葡萄球菌FtsZ与GTP形成的原丝纤维作比对,发现两个相邻的单体之间有一个50?的弯曲。这个弯曲的构象变化主要发生在T3-loop区,GTP的?-磷酸基团能够和T3环的主链胺基形成两个强氢键相互作用,从而锁定T3环处于一种紧密结合的构象(T构象),当FtsZ结合GDP时,失去了这两个强氢键相互作用后,T3环则处于一种松弛构象(R构象)。他们由此推测,当GTP水解为GDP时,GTP ?-磷酸基团和?-磷酸基团之间的共价键断裂,由于二者都携带负电荷,它们之间会产生一个巨大的排斥力,当二者被封闭在两个FtsZ亚基之间时,这个巨大的排斥力驱使GTP ?-磷酸基团推动T3环发生一个从紧密结合构象到松弛构象的构象变化,从而使两个相邻的FtsZ亚基围绕一个支点处发生弯曲,GTP水解的化学能就这样推动两个相邻FtsZ亚基之间发生一个相对弯曲。上述GTP水解而导致的FtsZ原丝纤维构象变化如何转化为细菌细胞分裂向内收缩的张力呢?叶升课题组进一步提出,FtsZ的C端肽链没有一个稳定的构象,这段肽段会和FtsA相结合,而FtsA通过它的C端一个疏水的?-螺旋粘在细胞膜上,Z环就是这样被固定在细胞膜上位于隔膜最内端。上述GTP水解而导致FtsZ原丝纤维的构象变化则通过FtsA施加一个改变细胞膜曲度的一个向内收缩的张力。该研究中,叶升课题组首次得到了细菌细胞FtsZ原丝纤维的结构,解决了细菌细胞分裂研究领域一个长期以来一直困扰生物学家们的问题,使我们从结构生物学角度更准确地理解细胞骨架自组装与调控机制。
The essential bacterial protein FtsZ is a guanosinetriphosphatase that self-assembles into a struc-ture at the division site termed the “Z ring”. During cytokinesis, the Z ring exerts a constrictive force on the membrane by using the chemical energy of guanosine triphosphate hydrolysis. However, the structural basis of this constriction remains unresolved. Here, we present the crystal structure of a guanosinediphosphate–bound Mycobacterium tuberculosis FtsZ protofilament, which exhibits a curved conformational state. The structure reveals a longitudinal interface that is important for function. The protofilament curvature highlights a hydrolysis-dependent conformational switch at the T3 loop that leads to longitudinal bending between subunits, which could generate sufficient force to drive cytokinesis.
通过关系网络学习外商投资所有权政策的案例研究
Case Studies on Learning Foreign Ownership Regulations in China through Relationship Networks
 [PDF]


Advances in Social Sciences (ASS) , 2016, DOI: 10.12677/ASS.2016.52049
Abstract:
本文旨在弄清对日资企业学习我国外商投资所有权政策起重要作用的关系网络。案例研究表明,关系网络的确对于学习外商投资所有权等政策起着重要作用,然而对于不同企业这种网络的组成不尽相同。在本文的三个案例中,有两个企业通过多种重要关系学习外商投资所有权政策,另一个企业在其网络中只有少数几个重要关系。尽管如此,在这三个企业的网络中都存在各自的关键也就是最重要的关系,例如日本/中国总部、政府和法律顾问。
This paper identified relationship networks that are important to Japanese ventures’ learning for-eign ownership regulations in China. Case studies showed that relationship networks are indeed important to learning government policies such as foreign ownership regulations but constituents in the network tend to be discrepant for different companies. Among our three cases, two are connected with multiple important relationships for learning foreign ownership regulations, while the other has only a few important relationships. Nevertheless, all of the three have key re-lationships in their own networks, such as Japanese/Chinese headquarters, government and law consultants.
口腔幽门螺杆菌尿素酶的检测及其临床意义
The Clinical Value of Oral H. Pylori Antigen Test
 [PDF]

国钦
Medical Diagnosis (MD) , 2012, DOI: 10.12677/MD.2012.24005
Abstract:
幽门螺杆菌(Hp)感染诊断方法很多,各种诊断方法有其各自的特点,但传统Hp感染的诊断方法,主要适用于胃Hp感染的检测,对口腔Hp感染难以做出稳定的检测结果,甚至存在检测盲区。唾液幽门螺杆菌抗原测试板(HPS),是应用胶体金层析式双抗体夹心法技术,采用Hp尿素酶单克隆抗体,定性检测人体唾液中相应Hp产生的尿素酶,主要应用于口腔Hp感染的检测,具有较高的敏感性和特异性,操作简便、快捷,可在实验室外进行检测等特点。HPSUBT联合检测,可大致区分口腔Hp感染合并胃Hp感染、单纯口腔Hp感染、单纯胃Hp感染,为临床制定更完善的、全新的Hp根除方案提供实验诊断依据。
There are number of diagnostic methods detecting Helicobacter pylori (H. pylori) infection. Each has their own character, however standard diagnosis technology apply in detecting H. pylori infection of stomach, not suitable for diagnosis of oral infection. For example, C13, C14 UBT test had been utilized as a gold standard for diagnosis of H. pylori infection in stomach more than two decades, however they have blinded zone detecting oral H. pylori infection. A simple
某工程冲孔灌注桩施工中钻孔偏斜的原因分析及处理措施
Bored of a Construction Project Drilling Skewed Cause Analysis and Treatment Measures
 [PDF]

维国
Hans Journal of Civil Engineering (HJCE) , 2014, DOI: 10.12677/HJCE.2014.35019
Abstract:
本文根据220 kV怀集变电站主控楼冲孔灌注桩施工偏孔的处理经验,总结出冲孔灌注桩施工过程中偏孔的原因主要有孔底土质不均、倾斜岩面、土层中夹有大的孤石或其它硬物及桩机安装就位稳定性差等,并提出预防和处理措施,为冲孔灌注桩施工提供借鉴和参考。
Based on the experiences of treatment to partial hole of the filling pile construction in Huaiji main control 220kV substation building, we summarized the main causes of the partial holes in the process of the filling pile construction. These causes include the uneven soil of hole bottom, inclined interface of stratum, large boulders or other hard objects in the soil and poor stability of the pile machine installation. At the same time, we put forward some suggestions on the prevention and treatment measures for avoiding partial hole in filling pile construction.
基于ADAMS的柔性混凝土泵车臂架仿真研究
Simulation of Flexible Arms of Truck-Mounted Concrete Pump Based on ADAMS
 [PDF]

张芸,
Software Engineering and Applications (SEA) , 2013, DOI: 10.12677/SEA.2013.26024
Abstract:
混凝土泵车臂架模型的正确创建对控制算法的研究有至关重要的作用。本文运用Pro/E建立与实物等比例大小的泵车模型,并导入ANSYS中进行网格划分,在ADAMS中替代刚性臂,构建柔性的混凝泵车臂架系统。在ADAMS中编写仿真脚本文件,结合传感器的使用,对泵车工作时常见的起动和制动过程进行了仿真。通过对柔性体模态阻尼比的设置,使柔性泵车模型如实反映混凝土泵车的工作状态,以此验证模型的正确性,为进一步的控制算法研究奠定了基础。
Creating a correct model of the arms of truck-mounted concrete pump plays a crucial role in studying on the control algorithm. In this paper, we establish a model with the same size of a real truck-mounted concrete pump in the software Pro/E and then export its arms into ANSYS for meshing. In ADAMS, we replace the rigid arms with those flexible ones to build a system of flexible arms of truck-mounted concrete pump truck. In addition, we write a simulation script file, combining with the use of sensors, to simulate the process in which the pump starts and brakes as it works in a real working condition. We set the flexible arms’ modal damping ratio to make the model reflect the working condition of a real concrete pump correctly. So we can verify the correctness of the model we establish and carry out further researches about the control algorithm based on the flexible model.
用格子Boltzmann方法分析太阳墙系统温度和速度的传输特性
Analysis of the ransfer Characteristics of the Temperature and Velocity in the Solar-Wall System by Lattice Boltzmann Method
 [PDF]

婧婕
Advances in Porous Flow (APF) , 2013, DOI: 10.12677/APF.2013.32005
Abstract:

本文主要应用格子Boltzmann方法研究太阳墙以及采暖房的热量传递和空气流动特性。通过改变参数,例如:风机的速度,多孔介质的孔隙度和上通道的直径等,进行数值模拟,研究在不同的参数下通过多孔介质的空气温度和流速,以及采暖房的温度分布等问题。数值模拟结果表明:参数的不同对流经多孔墙的空气的温度,以及采暖房的温度分布有着显著的影响,适当的选择参数可以有效的提高多孔墙的热利用率和房间的热舒适性。

In this paper, the characteristics of heat transfer and air flow in the solar wall and heated room are analyzed by Lattice Boltzmann Method simulation. We studied the air flow in the porous wall and the heat transfer of the heated room under different parameters, such as velocity of the fan, porosity of the porous medium and diameter of the upper channel etc. The results show that changing parameters have a remarkable effect on temperature of the air flowing through the porous medium and the heated room. As a result, choosing the parameters properly can effectively improve the heat utilization efficiency of the porous wall and the thermal comfort of the room.

古日古木-13治疗肝损伤的应用进展
The Progress in Application of Gurigumu-13 on Liver Injury
 [PDF]

超凡, 马丽杰
Pharmacy Information (PI) , 2014, DOI: 10.12677/PI.2014.32007
Abstract:

古日古木-13是蒙医常用药,本文对古日古木-13进行文献调研,阐述肝损伤的原因及古日古木-13的传统应用、临床应用,为该药的深入研究及进一步开发利用提供依据。
The Gurigumu-13 is the traditional Mongolian medicine widely used. In this paper, literature research to Gurigumu-13 was proceeded to explain the cause of the liver damage and the traditional use and the clinical research of Gurigumu-13, which provided the basis for the in-depth research and the further development.

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