The main reasons for the high content of inorganic N and its increase by several times in the Changjiang River and its mouth during the last 40 years were analysed in this work. The inorganic N in precipitation in the...The main reasons for the high content of inorganic N and its increase by several times in the Changjiang River and its mouth during the last 40 years were analysed in this work. The inorganic N in precipitation in the Changjiang River catchment mainly comes from gaseous loss of fertilizer N, N resulting from the increases of population and livestock, and from high temperature combustions of fossil fuels. N from precipitation is the first N source in the Changjiang River water and the only direct cause of high content of inorganic N in the Changjiang River and its mouth. The lost N in gaseous form and from agriculture non point sources fertilizer comprised about 60% of annual consumption of fertilizer N in the Changjiang River catchment and were key factors controlling the high content of inorganic N in the Changjiang River mouth. The fate of the N in precipitation and other N sources in the Changjiang River catchment are also discussed in this paper.展开更多
To make clear the precise hemodynamic mechanism underlying the anti-atherogenesis benefit of enhanced external couterpulsation(EECP) treatment, and to investigate the proper role of some important hemodynamic factors ...To make clear the precise hemodynamic mechanism underlying the anti-atherogenesis benefit of enhanced external couterpulsation(EECP) treatment, and to investigate the proper role of some important hemodynamic factors during the atherosclerotic progress, a comprehensive study combining long-term animal experiment and numerical solving was conducted in this paper. An experimentally induced hypercholesterolemic porcine model was developed and the chronic EECP intervention was subjected. Basic hemodynamic measurement was performed in vivo, as well as the arterial endothelial samples were extracted for physiological examination. Meanwhile, a numerical model was introduced to solve the complex hemodynamic factors such as WSS and OSI. The results show that EECP treatment resulted in significant increase of the instant levels of arterial WSS, blood pressure, and OSI. During EECP treatment, the instant OSI level of the common carotid arteries over cardiac cycles raised to a mean value of 8.58 ×10-2±2.13 ×10-2. Meanwhile, the chronic intervention of EECP treatment significantly reduced the atherosclerotic lesions in abdominal aortas and the endothelial cellular adherence. The present study suggests that the unique blood flow pattern induced by EECP treatment and the augmentation of WSS level in cardiac cycles may be the most important hemodynamic mechanism that contribute to its anti-atherogenesis effect. And as one of the indices that cause great concern in current hemodynamic study, OSI may not play a key role during the initiation of atherosclerosis.展开更多
文摘The main reasons for the high content of inorganic N and its increase by several times in the Changjiang River and its mouth during the last 40 years were analysed in this work. The inorganic N in precipitation in the Changjiang River catchment mainly comes from gaseous loss of fertilizer N, N resulting from the increases of population and livestock, and from high temperature combustions of fossil fuels. N from precipitation is the first N source in the Changjiang River water and the only direct cause of high content of inorganic N in the Changjiang River and its mouth. The lost N in gaseous form and from agriculture non point sources fertilizer comprised about 60% of annual consumption of fertilizer N in the Changjiang River catchment and were key factors controlling the high content of inorganic N in the Changjiang River mouth. The fate of the N in precipitation and other N sources in the Changjiang River catchment are also discussed in this paper.
基金Key Clinical Project from the Ministry of Healthgrant number:25400+1 种基金National Natural Science Foundation of Chinagrant number:81170272
文摘To make clear the precise hemodynamic mechanism underlying the anti-atherogenesis benefit of enhanced external couterpulsation(EECP) treatment, and to investigate the proper role of some important hemodynamic factors during the atherosclerotic progress, a comprehensive study combining long-term animal experiment and numerical solving was conducted in this paper. An experimentally induced hypercholesterolemic porcine model was developed and the chronic EECP intervention was subjected. Basic hemodynamic measurement was performed in vivo, as well as the arterial endothelial samples were extracted for physiological examination. Meanwhile, a numerical model was introduced to solve the complex hemodynamic factors such as WSS and OSI. The results show that EECP treatment resulted in significant increase of the instant levels of arterial WSS, blood pressure, and OSI. During EECP treatment, the instant OSI level of the common carotid arteries over cardiac cycles raised to a mean value of 8.58 ×10-2±2.13 ×10-2. Meanwhile, the chronic intervention of EECP treatment significantly reduced the atherosclerotic lesions in abdominal aortas and the endothelial cellular adherence. The present study suggests that the unique blood flow pattern induced by EECP treatment and the augmentation of WSS level in cardiac cycles may be the most important hemodynamic mechanism that contribute to its anti-atherogenesis effect. And as one of the indices that cause great concern in current hemodynamic study, OSI may not play a key role during the initiation of atherosclerosis.