广西各地级市形象的“他者”再现——基于域外纸媒有关广西的报道为样本

城市形象是城市软实力的重要组成部分,从媒体视角看,城市形象往往是通过域内媒体"自塑"和域外媒体"他塑"相结合的方式建构的。本文以域外媒体有关广西各市的报道为研究对象,通过对相关报道样本的框架分析,探究广西各市城市形象的"他者"再现规律,给广西各市城市形象的域外传播带来新启示。

Multivariable temperature measurement and control system of large-scaled vertical quench furnace based on temperature field

A temperature control system of 31m vertical forced air-circulation quench furnace is proposed, which is a kind of equipment critical for thermal treatment of aluminum alloy components that are widely used in aerospace industry. For the effective operation of the furnace, it is essential to analyze the radial temperature distribution of the furnace. A set of thermodynamic balance equations modeling is established firsdy. By utilizing the numerical analysis result to modify the temperature measurements, the control accuracy and precision of the temperature are truly guaranteed. Furthermore, the multivariable decoupling self-learning PID control algorithm based on the characteristics of strong coupling between the multi-zones in the large-scaled furnace is implemented to ensure the true homogeneity of the axial temperature distribution. Finally, the redundant structure composed of industrial control computers and touch panels leads to great improvement of system reliability.

推拿手法对神经病理痛大鼠背根神经节和脊髓背角NMDAR2B表达的影响

目的通过观察坐骨神经慢性压迫性损伤大鼠模型(CCI)大鼠背根神经节和脊髓背角N-甲基-D-天冬氨酸(NMDA)受体2B亚单位(NR2B)的表达和推拿手法干预对其的影响,探讨推拿手法干预神经病理痛的作用机制。方法清洁级雄性SD大鼠,随机分成空白组、假手术组、CCI模型组、CCI模型+推拿组,每组8只。空白组不做任何处理;假手术组只分离坐骨神经但不进行结扎;CCI模型组及CCI模型+推拿组均参照Bennett G J的方法稍作改进制备神经病理痛模型;CCI模型+推拿组于造模后第4~17天实施每天1次、每次10 min的推拿干预。疗程结束后Western blot检测背根神经节和脊髓背角组织NR2B蛋白的表达。结果与空白组、假手术组相比,CCI模型组、CCI+推拿组的背根神经节NMDAR2B的表达量均上调(P <0. 01);CCI模型组、CCI+推拿组的背根神经节NMDAR2B的表达量的差异无统计学意义(P> 0. 05)。与空白组、假手术组相比,CCI模型组的脊髓背角NMDAR2B的表达量上调(P <0. 01);与CCI模型组比较,CCI+推拿组的脊髓背角NMDAR2B的表达量被逆转(P <0. 05)。结论背根神经节和脊髓背角NMDA受体亚单位NR2B参与大鼠神经病理痛的形成和维持,推拿手法可通过抑制脊髓NR2B蛋白表达,从而抑制脊髓背角中枢敏化以发挥镇痛的作用。