The number of bamboo stem at different ages and the mean diameter at breast height(DBH)which are the important target in evaluating productivity of bamboo stand were investigated in 50 plots established in Jianou city...The number of bamboo stem at different ages and the mean diameter at breast height(DBH)which are the important target in evaluating productivity of bamboo stand were investigated in 50 plots established in Jianou city, Fujian Province in this paper, and the authors selected the method of artificial neural network to biuld the simulative and predictive model of mean DBH for bamboo stands. Artificial neural network is a good method in handling the overall nonlinear mapping problems between input variables and output ones, which has a wide application in many research fields, such as system simulating, automation controlling, paralleled data processing and so on. In this paper, the input variables were the number of different age and the total number of stand, the output variable was mean DBH for bamboo stands, the number of neurons of hide level( M ) was M=2L+1=3 according to the last document ( L is the number of factors of input level), and the network activity function is Sigmiod function as follows: F(x)=1/(1+e -x ). Using the built BP network, the samples were trained until E j(W 1 lm ,W 2 mn )=Nn=1(O nj -Y nj ) 2 =min, where O nj and Y nj are output values of network and really values of DBH for bamboo stands respectively, N is the number of trained samples, and E j is sum of square deviation of BP network. If E j didn’t converge, the weights and thresholds of BP network were adjusted as follow: ΔW ij (n+1)=βλ jX i+αΔW ij (n) and Δη j(n+1)=-βλ j+αΔη j(n) .. The results showed that the mean simulative accuracy and the mean predictive accuracy of mean D.B.H BP model for bamboo stands were all satisfactory, which were 89 95% and 89 26% respectively. Therefore, it provided a scientific basis for evaluating the productivity and realizing high yield for bamboo stands.展开更多
After cerebral ischemia, bone marrow mesenchymal stem cells are mobilized and travel from the bone marrow through peripheral circulation to the focal point of ischemia to initiate tissue regeneration. However, the num...After cerebral ischemia, bone marrow mesenchymal stem cells are mobilized and travel from the bone marrow through peripheral circulation to the focal point of ischemia to initiate tissue regeneration. However, the number of bone marrow mesenchymal stem cells mobilized into peripheral circulation is not enough to exert therapeutic effects, and the method by which blood circulation is promoted to remove blood stasis influences stem cell homing. The main ingredient of Xuesaitong capsules is Panax notoginseng saponins, and Xuesaitong is one of the main drugs used for promoting blood circulation and removing blood stasis. We established rat models of cerebral infarction by occlusion of the middle cerebral artery and then intragastrically administered Xuesaitong capsules（20, 40 and 60 mg/kg per day） for 28 successive days. Enzyme-linked immunosorbent assay showed that in rats with cerebral infarction, middle- and high-dose Xuesaitong significantly increased the level of stem cell factors and the number of CD117-positive cells in plasma and bone marrow and significantly decreased the number of CD54-and CD106-positive cells in plasma and bone marrow. The effect of low-dose Xuesaitong on these factors was not obvious. These findings demonstrate that middle- and high-dose Xuesaitong and hence Panax notoginseng saponins promote and increase the level and mobilization of bone marrow mesenchymal stem cells in peripheral blood.展开更多
文摘The number of bamboo stem at different ages and the mean diameter at breast height(DBH)which are the important target in evaluating productivity of bamboo stand were investigated in 50 plots established in Jianou city, Fujian Province in this paper, and the authors selected the method of artificial neural network to biuld the simulative and predictive model of mean DBH for bamboo stands. Artificial neural network is a good method in handling the overall nonlinear mapping problems between input variables and output ones, which has a wide application in many research fields, such as system simulating, automation controlling, paralleled data processing and so on. In this paper, the input variables were the number of different age and the total number of stand, the output variable was mean DBH for bamboo stands, the number of neurons of hide level( M ) was M=2L+1=3 according to the last document ( L is the number of factors of input level), and the network activity function is Sigmiod function as follows: F(x)=1/(1+e -x ). Using the built BP network, the samples were trained until E j(W 1 lm ,W 2 mn )=Nn=1(O nj -Y nj ) 2 =min, where O nj and Y nj are output values of network and really values of DBH for bamboo stands respectively, N is the number of trained samples, and E j is sum of square deviation of BP network. If E j didn’t converge, the weights and thresholds of BP network were adjusted as follow: ΔW ij (n+1)=βλ jX i+αΔW ij (n) and Δη j(n+1)=-βλ j+αΔη j(n) .. The results showed that the mean simulative accuracy and the mean predictive accuracy of mean D.B.H BP model for bamboo stands were all satisfactory, which were 89 95% and 89 26% respectively. Therefore, it provided a scientific basis for evaluating the productivity and realizing high yield for bamboo stands.
基金financially supported by a grant from Henan Medical Science and Technology Innovative Talents Project in 2010,No.1041000510010
文摘After cerebral ischemia, bone marrow mesenchymal stem cells are mobilized and travel from the bone marrow through peripheral circulation to the focal point of ischemia to initiate tissue regeneration. However, the number of bone marrow mesenchymal stem cells mobilized into peripheral circulation is not enough to exert therapeutic effects, and the method by which blood circulation is promoted to remove blood stasis influences stem cell homing. The main ingredient of Xuesaitong capsules is Panax notoginseng saponins, and Xuesaitong is one of the main drugs used for promoting blood circulation and removing blood stasis. We established rat models of cerebral infarction by occlusion of the middle cerebral artery and then intragastrically administered Xuesaitong capsules（20, 40 and 60 mg/kg per day） for 28 successive days. Enzyme-linked immunosorbent assay showed that in rats with cerebral infarction, middle- and high-dose Xuesaitong significantly increased the level of stem cell factors and the number of CD117-positive cells in plasma and bone marrow and significantly decreased the number of CD54-and CD106-positive cells in plasma and bone marrow. The effect of low-dose Xuesaitong on these factors was not obvious. These findings demonstrate that middle- and high-dose Xuesaitong and hence Panax notoginseng saponins promote and increase the level and mobilization of bone marrow mesenchymal stem cells in peripheral blood.
