A new perspective of ecosystem health

Ecosystem health has attracted considerable attention from different disciplines in recent years. However, it still remains a disputed issue whether to focus on its general concept or on operational practice. As a result, these disputations have caused confusion and limited further research in the field of ecosystem health. In this paper, we attempt to introduce a new perspective to the concept of ecosystem health. With the aid of modern statistical methodology, such as factor analysis and normal distribution theory, we provide a conceptual approach to the quantitative assessment of ecosystem health and our method could be applied to various categories of ecosystems.

肝脏代谢分区研究进展

肝脏是机体最重要的器官之一,扮演去氧化、储存肝糖原和合成分泌性蛋白的角色。肝脏合成与生物转化过程中依赖酶促反应的高效催化。在进化与适应的过程中,肝脏演化出代谢分区的功能性组织结构,使不同酶促反应呈现出空间特异性分布,使肝脏对空间和资源实现最大化利用,保证肝脏功能的高效运转和内环境稳态。同样,当暴露于各种损伤因素时,肝脏病理改变也呈现出空间特异性分布的特点,在复杂信号调控网络的作用下,维持肝脏损伤与修复的平衡。本文旨在系统综述肝脏组织和代谢分区的相关研究,以期为理解肝脏生理功能的维持机制及临床治疗肝脏疾病寻找新的治疗靶点。

互联大电网安全稳定控制协调方案研究

安全稳定控制系统间缺乏协调配合是酿成大停电事故的重要原因之一。对互联大电网的安全稳定控制存在的两类协调问题进行了描述,并从切机、切负荷引起区域电磁功率突变和联络线功率波动入手,基于联络线波动功率幅值近似计算公式,分析了局部安控引起区域失稳问题的可能原因。在此基础上给出了安全稳定控制的协调配合建议,并在IEEE-39节点系统中对两大协调问题进行了实例阐释。