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Urban development management is a global trend, and an urgent requirement in Vietnam today. In recent years, urban development in the southwestern region along the trend of adaptation to climate change has received the attention of the Party and the State; at the same time achieve certain results. However, the management of urban development in the southwestern region adapting to climate change is still inadequate, requiring more robust, systematic and synchronized measures in the development process and urban management in the Southwest region.

The objective of this study is to analyze the effects of suspension design parameters of a semi-trailer truck on vehicle ride comfort as well as road surface friendliness. A half-dynamic vehicle model with 12° of freedom is established under random road excitation. The weighted root mean square (RMS) of acceleration responses of the vertical driver’s seat, cab’s pitch and dynamic load coefficient (DLC) is chosen as an objective function which uses Matlab/Simulink software to simulate the vehicle dynamics model and calculate the objective functions. The effects of suspension design parameters of a semi-trailer truck such as stiffness and damping coefficients on the objective functions are analyzed respectively. The results show that the effects of the stiffness and damping parameters in the suspension systems on the vehicle ride comfort as well as road surface friendliness are very obvious. The worse the vehicle ride comfort as well as road surface friendliness is, the greater the stiffness of the suspension systems is. However, the vehicle ride comfort improves with the increase of the damping of the suspension systems. Therefore, the study provides a theoretical basis for the suspension system design of semi-trailer trucks.

Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease. Epidemiological studies have demonstrated that cigarette smoke or nicotine is a risk factor for the progression of chronic kidney injury. The present study analyzed the kidney toxicity of cigarette smoke in experimental rats with DKD. Experimental diabetes was induced in 7-week-old Sprague-Dawley rats by a single intraperitoneal injection of streptozotocin (60 mg kg−1). Four weeks after the induction of diabetes, rats were exposed to cigarette smoke (200 μg L−1), 4 h daily, and 5 days per week for 4 weeks. Cigarette smoke did not affect the levels of plasma glucose, hemoglobin A1c, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol or non-esterified fatty acids in both control and diabetic rats under the experimental conditions. Cigarette smoke, however, significantly increased diabetes-induced glomerular hypertrophy and urinary kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) excretion, suggesting exacerbation of diabetic kidney injury. Cigarette smoke promoted macrophage infiltration and fibrosis in the diabetic kidney. As expected, cigarette smoke increased oxidative stress in both control and diabetic rats. These data demonstrated that four weeks of exposure to cigarette smoke aggravated the progression of DKD in rats.