Complex Pathways to Population Shrinkage:Case Study of Hegang City,China

With the transformation of China’s industry and demographic structure,urban shrinkage,especially the resource-based cities due to their single industrial structure,tend to emerge gradually.Using empirical and quantitative methods,this paper explores the evolution mechanism of urban shrinkage in Hegang,a resource-based city in China.Our findings suggest that there are many correlations or cyclic relationships among variables,which provide an empirical confirmation for the complexity of urban shrinkage process.The result shows there is a time delay of about four to five years between the mining industry and the changes of demographic profile,economic performance and built environment variables.The development of Hegang has formed a path dependence on resource-based industries.Furthermore,the time lags between demographic profile and economic performance variables are not obvious,and the real estate market has a certain sensitivity to perceive population loss and economic change.Besides,market led public service facilities are more sensitive to the changes of population outflow and economic recession than government led public service facilities.The study findings could offer insights for other resource-based cities in developing countries to employ on the economic development policies issues.

Gamma-aminobutyric acid A receptors in Alzheimer＇s disease： highly localized remodeling of a complex and diverse signaling pathway

Alzheimer＇s disease （AD）, the predominant form of dementia, is a chronic, incurable neurodegenerative disorder presenting with symptoms includ- ing progressive memory loss and disturbed emotional state. It has been estimated that dementia affects over 47 million people worldwide （Prince et al., 2015）, and with 60-80% of cases attributable to AD.

The Reconstruction Technique of Multi-Product Production and MINLP Mathematical Modelling

Low efficiency, negative impacts on the environment and non-profitable operations are the main shortcomings of out-dated industrial processes. Such systems can be reconstructed and improved in the direction of multi-product operations. The study of this article focuses on the development of a method for multi-product operations by reconstructing out-dated industrial processes. This article contains the theory of a developed method that enables the updating of existing process units and integrated systems on the basis of reconstruction scenarios and pathways. The goals of the set out method are: 1) to maintain the existing process units and chemical plants to a greater extent, 2) to enable the potential for finding new process alternatives and technological solutions, 3) to provide a streamlined operation for all subsystems and total systems, 4) to promote environmental and social responsibilities, and 5) to apply the concept of the presented reconstruction method to non-profitable industrial processes. In regard to multi-product operations, a conceptual model is a suitable tool for the reconstruction of industrial processes. It connects several software tools and so enables quick decision-making between process alternatives. A reconstruction method provides foresight into the possible improvements to existing industrial processes. In comparison with the indirect synthesis of DME (simple reconstruction pathway), the lower operating costs from the direct synthesis of DME (complex reconstruction pathway) were confirmed.