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961.
Integrins are heterodimeric glycoproteins that have been found to undergo dynamic temporal and spatial changes in the endometrium during the menstrual cycle and in early pregnancy. Specificity of integrins is known to be different in human endometrial stromal cells and decidual cells. These shifts of integrins suggested to play an important role in embryo implantation and can be modulated by progesterone, cAMP derivatives, and cytokines. The mechanisms of decidualization and its precise physiological role are still not clearly understood and in vitro systems could provide an alternative that overcomes limitations of studying such complex biological phenomena in vivo at the time of implantation. This study was undertaken to establish an in vitro model system for human decidualization using 8-bromo-cAMP and to investigate the characteristics of stromal integrin expression in vitro by 8-Br-cAMP. Endometrial stromal cells were isolated and cultured, and then were induced to decidualize by 0.5 mM 8-Br-cAMP for 15 days. Immunofluorescence staining and flow cytometric analyses of the integrin subunits (alpha1, alpha4, alpha5, alpha6, beta1 and alphavbeta3) were performed at day 9. In the presence of 8-Br-cAMP, the staining intensity of alphavbeta3 was significantly higher than control and measurements for alpha1, alpha4, alpha5, alpha6, and beta1 were similar. Immunofluorescent localization of the integrins reflected the differences obtained from the flow cytometric analyses described above. In summary, the expression of alphavbeta3 integrin increased in stromal cells in vitro decidualized by 8-Br-cAMP and this up-regulation of alphavbeta3 integrin expression during decidualization might influence on human implantation. 相似文献
962.
963.
Potential Analysis - Using coupling by change of measure and an approximation technique, Wang’s Harnack inequalities are established for a class of functional SDEs driven by subordinate... 相似文献
964.
针对点阵夹层结构主动热防护问题,建立了夹层结构面板和芯体导热与冷却剂对流耦合的非稳态传热理论模型,利用有限体积法离散控制方程并在MATLAB中进行了迭代求解.模型首次考虑了面板与夹芯杆之间的收缩热阻,并利用分离变量法得到了收缩热阻的近似解析解.基于单胞模型和周期性边界条件,模拟得到了模型所需的表面对流传热系数h_(b)和h_(fin).最后,选取多单胞计算工况进行数值模拟和理论模型对比,并讨论了收缩热阻对模型预测精度的影响.结果表明:理论模型能够准确预测夹层结构及内部流体的温度变化,理论与仿真之间的最大误差不超过1%;随着外加热流密度不断增大,忽略收缩热阻使得计算结果造成的误差不断增大;与数值模拟相比,理论模型可显著地减少计算时间并节省计算资源,尤其适用于非均匀、非稳态复杂热载荷下点阵夹层结构的温度响应计算. 相似文献
965.
Acta Mathematicae Applicatae Sinica, English Series - A bio-safe dengue control strategy is to use Wolbachia, which can induce incomplete cytoplasmic incompatibility (CI) and reduce the mating... 相似文献
966.
Elastic Analysis of Anisotropic Functionally Graded Rotating Disks With Non-Uniform Thicknesses北大核心CSCD 下载免费PDF全文
研究了任意梯度变化的变厚度各向异性转动圆盘的弹性问题.假设圆盘绕刚性轴匀速转动,其材料性能和厚度沿径向任意梯度变化.考虑圆盘在中心转轴处受位移约束,外侧自由,根据各向异性转动圆盘的平衡微分方程,得到关于径向应力的Fredholm积分方程,继而通过对Fredholm积分方程进行数值求解,得到结构的位移场和应力场.对具体梯度变化情况仅需代入相应梯度变化进行求解即可.数值算例部分,通过假设厚度、弹性模量等参数为特殊的幂函数形式,将由Fredholm积分方程求出的数值解与对应的精确解进行对比,以及针对常见的Voigt模型,将由该方法算得的数值解和ANSYS有限元计算结果进行对比,验证了该方法的准确性和精度.其次,针对Voigt模型,重点分析了厚度变化、材料性能梯度参数、各向异性度等对应力场和位移场的影响.提出了针对材料性能和厚度沿径向呈任意梯度变化的圆盘结构弹性分析方法,将为优化功能梯度圆盘的结构和材料参数、有效调整构件应力分布、提高结构安全性,提供强有力的工具;算例分析结果对功能梯度圆盘在复杂条件下的结构安全设计有重要的理论指导意义. 相似文献
967.
Impact Responses of Prismatic Lithium-Ion Battery Based on the Membrane Factor Method北大核心CSCD 下载免费PDF全文
Aimed at the internal short circuit problem due to large deformation of the prismatic lithium-ion battery cell under impact loadings, a simplified battery model was first established. Then the motion equations of velocity and displacement based on the membrane factor method were proposed. With the effects of the face-sheet thickness and the densification region on the normalized final deflection, impact response characteristics of prismatic battery cells were investigated in detail. The results show that, the improved motion equations involving the membrane factor can reflect the dynamic response mechanisms of the prismatic battery cell under impact loadings, and the large deflection under high-speed impact can be predicted. With the increase of the face-sheet thickness, the deflection of the battery cell’s lower part decreases obviously. However, the densification region expands with the face-sheet thickness. The deflection and the densification region of the cell’s lower part both increase with the inner core density of the battery. This proposed impact model provides a theoretical guidance for the multi-functional integrated dynamic design of prismatic battery cells. © 2022 Editorial Office of Applied Mathematics and Mechanics. All rights reserved. 相似文献
968.
Hui Jin Yan-bing Hou Xian-guo Meng Feng Teng 《高分子科学》2006,(6):553-558
In this paper, photoexcitation processes in the bilayer devices based on inorganic materials and poly(N-vinylcarbazole) (PVK) were investigated. In order to clarify the roles of inorganic materials in photoconductive properties of bilayer devices, TiO2 and ZnS were chosen to combine with PVK. A model for generation of photocurrent (Iph) in single layer device of PVK was obtained. It is deduced that the recombination rate constant (Pcomb) and the ionization rate constant (y) ofexcitons should be considered as the most important factors for Iph. For inorganic materials (TiO2 or ZnS)/PVK bilayer devices, in reverse bias of-4 V, the photocurrent of 115 mA/cm^2 in the TiO2/PVK device was observed, but the photocurrent in the ZnS/PVK device was only 10 mA/cma under the illumination light of 340 nm and the light intensity of 14.2 mW/cm^2. The weaker photocurrent is attributed to the absorption of ZnS within UV region and the energy offset at the interface between PVK and ZnS, which impedes the transport of charge carriers. 相似文献
969.
X. Y. Zhang S. Jin Y. C. Liang Y. F. Ming L. H. Yu M. G. Fan W. F. Wang S. D. Yao 《Research on Chemical Intermediates》1995,21(1):17-24
Photochromic reactions of four indolinospirooxazine derivatives have been studied using nanosecond laser flash photolysis
techniques. Photolysis of the four compounds in acetonitrile and in cyclohexane all leads to the formation of the short-lived
CT intermediates as the predominant photoproducts. In certain circumstances few photomerocyanines (PMC) can be observed. From
the absorption bands and the lifetimes of CT intermediates, it has been speculated that the substituents at the nitrogen atom
of the indole ring influence the structural characteristics of CT intermediates mainly through steric hindrance effects, whereas
the substituents at the 5 position of the indoline ring influence mainly through electron effects. A potential energy surface
model is established to explain the results. 相似文献
970.
An augmented Lagrange algorithm for nonlinear optimizations with second-order cone constraints is proposed based on a Löwner operator associated with a potential function for the optimization problems with inequality constraints. The favorable properties of both the Löwner operator and the corresponding augmented Lagrangian are discussed. And under some mild assumptions, the rate of convergence of the augmented Lagrange algorithm is studied in detail. 相似文献