F_1-ATPase, a part of ATP synthase, can synthesize and hydrolyze ATP moleculars in which the centralγ-subunit rotates inside the α_3β_3 cylinder.A stochastic four-state mechanochemical coupling model of F_1-ATPase ...F_1-ATPase, a part of ATP synthase, can synthesize and hydrolyze ATP moleculars in which the centralγ-subunit rotates inside the α_3β_3 cylinder.A stochastic four-state mechanochemical coupling model of F_1-ATPase isstudied with the aid of the master equation.In this model, the ATP hydrolysis and synthesis are dependent on ATP,ADP, and Pi concentrations.The effects of ATP concentration, ADP concentration, and the external torque on theoccupation probability of binding-state, the rotation rate and the diffusion coefficient of F_1-ATPase are investigated.Moreover, the results from this model are compared with experiments.The mechanochemical mechanism F_1-ATPase isqualitatively explained by the model.展开更多
A new analysis of a previously studied traveling agent model, showed that there is a relation between the degree of homogeneity of the medium where the agents move, agent motion patterns, and the noise generated from ...A new analysis of a previously studied traveling agent model, showed that there is a relation between the degree of homogeneity of the medium where the agents move, agent motion patterns, and the noise generated from their displacements. We proved that for a particular value of homogeneity, the system self organizes in a state where the agents carry out Lévy walks and the displacement signal corresponds to 1/f noise. Using probabilistic arguments, we conjectured that 1/f noise is a fingerprint of a statistical phase transition, from randomness (disorder) to predictability (order), and that it emerges from the contextuality nature of the system which generates it.展开更多
Objective：To investigate the expression of cyclooxygenase-2 and its pathological effect in the experimental nonalcoholic fatty liver of rats, and to explore its possible mechanism. Methods：The rat NAFLD model was es...Objective：To investigate the expression of cyclooxygenase-2 and its pathological effect in the experimental nonalcoholic fatty liver of rats, and to explore its possible mechanism. Methods：The rat NAFLD model was established by giving a fat-enriched diet. The blood samples were obtained form abdominal aorta and the levels of serum ALT, AST and IL-1, changes in the hepatic tissue 6-k-PGF1 α TXB2 were measured. The expression level of COX-2 in rats livers were assayed by immunohistochemistry, RT-PCR and Westernblot. Results： Light microscope analysis revealed that hepatocytes were injured in the model group and slightly in the treatment group. The levels of serum TXB2 and IL-1 in the fatty liver rats were increased. Compared with the model group, the IL-1 and TXB2 increased significantly（P〈 0.05）, on the contrary, compared with the normal group, the hepatic tissue 6-Keto-prostagland decreased significantly in the model group（P 〈 0.05）, the treatment group also increased but P 〉 0.05. There was no positive expression of COX-2 in hepatic tissue of normal rats. In the model group, there was positive expression of COX-2 antigen and the number of COX positive cells progressively increased at 4, 8, 12 wks. The intensity of expression of COX-2 had significantly increased（P 〈 0.05 ） and the intensity of COX-2 expression in the treated group decreased remarkably compared with the model group（P 〈 0.05）. The expression of COX-2 mRNA and the level of COX-2 protein were significantly stronger in the liver of model rats compared with normal rats, and significantly weaker in treated rats, than in 8W and 12W model rats（P 〈 0.05）. Conclusion：The increase of COX-2 expression in NAFLD is closely associated with the severity of liver inflammation and damage. COX-2 may play an important role in the progression of rat NAFLD, and the expression of COX-2 mRNA is downregulated by cyclooxygenase-2 inhibitor, which can depress the oxidative stress and control inflammatory response efficiently.展开更多
BACKGROUND： Pharmacological experiments have demonstrated that gastrodin has a protective effect on neonatal rat brain subjected to hypoxia-ischemia; however, the underlying mechanism has not been fully elucidated. O...BACKGROUND： Pharmacological experiments have demonstrated that gastrodin has a protective effect on neonatal rat brain subjected to hypoxia-ischemia; however, the underlying mechanism has not been fully elucidated. OBJECTIVE： The aim of this study was to investigate the acute therapeutic effects of gastrodin by observing prostaglandin B2 and 6-keto-prostaglandin F 1 a in brain tissue of neonatal rats that received gastrodin injections immediately after hypoxia-ischemia. DESIGN： Single-factor design. SETTING： Department of Pediatrics, Affiliated Hospital of Yanbian University. MATERIALS： This study was performed in the Laboratory of the Department of Pediatrics, Affiliated Hospital of Yanbian University （key laboratory of provincial Health Department） from April to December 2003. Fifty-five Wistar rats of either gender, aged 7 days, were provided by the Laboratory Animal Center of Affiliated Hospital of Yanbian University. The rats were randomly divided into normal control （n =10）, model （n = 15）, gastrodin-treated （n = 15）, and Danshen-treated （n = 15） groups. The protocol was performed in accordance with guidelines from the Institute of Health Sciences for the use and care of animals. The following reagents were. used： Gastrodin （Sancai Medicine Group Co., Ltd., Zhongshan, Guangdong Province, China; component： gastrodin）, Danshen （Conba Stock Company, Jinhua, Zhengjiang Province, China; component： salvia miltiorrhiza）, and reagent kits for ^125I-prostaglandin B2 and ^125I-6-prostaglandin F l a （Research and Development Center for Science and Technology, General Hospital of Chinese PLA）. METHODS： Rats in the normal control group received no treatment. Rats in the remaining 3 groups were anesthetized, followed by ligation of the left common carotid artery. One hour later, the rats were placed in a closed hypoxic box and allowed to inhale 8% oxygen-air （2.0 3.0 L/min） for 2 hours to develop hypoxic-ischemic encephalopathy. Immediately after lesion, rats in the gastrodin and Danshen-treated groups were intraperitoneally injected with l g gastrodin （10 mL/kg） and 15 g Danshen （l 5 mL/kg）, respectively. MAIN OUTCOME MEASURES： Forty-eight hours after lesion, the left brain hemisphere was removed and homogenized to test the levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a by radioimmunoassay. RESULTS： Forty successfully lesioned neonatal rats from the model, gastrodin-treated, and Danshen-treated groups, and ten rats from the control group, were included in the final analysis. Levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a in brain tissue of neonatal rats were significantly higher in the model group than in the control group （both P 〈 0.01）. Levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a were significantly lower in the gastrodin-treated and the Danshen-treated groups compared to the model group （all P 〈 0.01）. However, there were no significant differences in levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a between the gastrodin-treated and the Danshen-treated groups （P 〉 0.05）. CONCLUSION： Gastrodin decreased prostaglandin and thromboxan levels in neonatal rat brains subjected to hypoxia-ischemia.展开更多
LightGBM is an open-source, distributed and high-performance GB framework built by Microsoft company. LightGBM has some advantages such as fast learning speed, high parallelism efficiency and high-volume data, and so ...LightGBM is an open-source, distributed and high-performance GB framework built by Microsoft company. LightGBM has some advantages such as fast learning speed, high parallelism efficiency and high-volume data, and so on. Based on the open data set of credit card in Taiwan, five data mining methods, Logistic regression, SVM, neural network, Xgboost and LightGBM, are compared in this paper. The results show that the AUC, F1-Score and the predictive correct ratio of LightGBM are the best, and that of Xgboost is second. It indicates that LightGBM or Xgboost has a good performance in the prediction of categorical response variables and has a good application value in the big data era.展开更多
A model-independent 3-D texture synthesis of physical and stochastic algorithms,based on an amplitude modulation method,is presented to realize 3-D fabric dynamic simulation.The physical functions are built to simulat...A model-independent 3-D texture synthesis of physical and stochastic algorithms,based on an amplitude modulation method,is presented to realize 3-D fabric dynamic simulation.The physical functions are built to simulate fabric basic deformation.The stochastic functions,generated by Perlin noise,are used to simulate fabric natural motion in the wind.The two kinds of functions are synthesized by method of amplitude modulation.As the arithmetic uses stochastic functions in stead of recursive algorithm,it is capable of simulating the fabric material,the wind force and direction in real-time.Given the fabric material and wind strength,the stochastic functions can be created to simulate fabric motion in the wind and this model can be adjusted by controlling some certain parameters to achieve a good simulation effect.This method is conceptually intuitive,computationally fast and efficient.Furthermore,the combination of fabric physical and statistic motion characteristics provides an attractive way to improve the display effect and rate.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.10847118the National Natural Science Foundation of the City of Tianjin under Grant No.08JCYBJC00900 the Science Research Program of Education office of Hebei Province under Grant No.2008427
文摘F_1-ATPase, a part of ATP synthase, can synthesize and hydrolyze ATP moleculars in which the centralγ-subunit rotates inside the α_3β_3 cylinder.A stochastic four-state mechanochemical coupling model of F_1-ATPase isstudied with the aid of the master equation.In this model, the ATP hydrolysis and synthesis are dependent on ATP,ADP, and Pi concentrations.The effects of ATP concentration, ADP concentration, and the external torque on theoccupation probability of binding-state, the rotation rate and the diffusion coefficient of F_1-ATPase are investigated.Moreover, the results from this model are compared with experiments.The mechanochemical mechanism F_1-ATPase isqualitatively explained by the model.
文摘A new analysis of a previously studied traveling agent model, showed that there is a relation between the degree of homogeneity of the medium where the agents move, agent motion patterns, and the noise generated from their displacements. We proved that for a particular value of homogeneity, the system self organizes in a state where the agents carry out Lévy walks and the displacement signal corresponds to 1/f noise. Using probabilistic arguments, we conjectured that 1/f noise is a fingerprint of a statistical phase transition, from randomness (disorder) to predictability (order), and that it emerges from the contextuality nature of the system which generates it.
文摘Objective：To investigate the expression of cyclooxygenase-2 and its pathological effect in the experimental nonalcoholic fatty liver of rats, and to explore its possible mechanism. Methods：The rat NAFLD model was established by giving a fat-enriched diet. The blood samples were obtained form abdominal aorta and the levels of serum ALT, AST and IL-1, changes in the hepatic tissue 6-k-PGF1 α TXB2 were measured. The expression level of COX-2 in rats livers were assayed by immunohistochemistry, RT-PCR and Westernblot. Results： Light microscope analysis revealed that hepatocytes were injured in the model group and slightly in the treatment group. The levels of serum TXB2 and IL-1 in the fatty liver rats were increased. Compared with the model group, the IL-1 and TXB2 increased significantly（P〈 0.05）, on the contrary, compared with the normal group, the hepatic tissue 6-Keto-prostagland decreased significantly in the model group（P 〈 0.05）, the treatment group also increased but P 〉 0.05. There was no positive expression of COX-2 in hepatic tissue of normal rats. In the model group, there was positive expression of COX-2 antigen and the number of COX positive cells progressively increased at 4, 8, 12 wks. The intensity of expression of COX-2 had significantly increased（P 〈 0.05 ） and the intensity of COX-2 expression in the treated group decreased remarkably compared with the model group（P 〈 0.05）. The expression of COX-2 mRNA and the level of COX-2 protein were significantly stronger in the liver of model rats compared with normal rats, and significantly weaker in treated rats, than in 8W and 12W model rats（P 〈 0.05）. Conclusion：The increase of COX-2 expression in NAFLD is closely associated with the severity of liver inflammation and damage. COX-2 may play an important role in the progression of rat NAFLD, and the expression of COX-2 mRNA is downregulated by cyclooxygenase-2 inhibitor, which can depress the oxidative stress and control inflammatory response efficiently.
文摘BACKGROUND： Pharmacological experiments have demonstrated that gastrodin has a protective effect on neonatal rat brain subjected to hypoxia-ischemia; however, the underlying mechanism has not been fully elucidated. OBJECTIVE： The aim of this study was to investigate the acute therapeutic effects of gastrodin by observing prostaglandin B2 and 6-keto-prostaglandin F 1 a in brain tissue of neonatal rats that received gastrodin injections immediately after hypoxia-ischemia. DESIGN： Single-factor design. SETTING： Department of Pediatrics, Affiliated Hospital of Yanbian University. MATERIALS： This study was performed in the Laboratory of the Department of Pediatrics, Affiliated Hospital of Yanbian University （key laboratory of provincial Health Department） from April to December 2003. Fifty-five Wistar rats of either gender, aged 7 days, were provided by the Laboratory Animal Center of Affiliated Hospital of Yanbian University. The rats were randomly divided into normal control （n =10）, model （n = 15）, gastrodin-treated （n = 15）, and Danshen-treated （n = 15） groups. The protocol was performed in accordance with guidelines from the Institute of Health Sciences for the use and care of animals. The following reagents were. used： Gastrodin （Sancai Medicine Group Co., Ltd., Zhongshan, Guangdong Province, China; component： gastrodin）, Danshen （Conba Stock Company, Jinhua, Zhengjiang Province, China; component： salvia miltiorrhiza）, and reagent kits for ^125I-prostaglandin B2 and ^125I-6-prostaglandin F l a （Research and Development Center for Science and Technology, General Hospital of Chinese PLA）. METHODS： Rats in the normal control group received no treatment. Rats in the remaining 3 groups were anesthetized, followed by ligation of the left common carotid artery. One hour later, the rats were placed in a closed hypoxic box and allowed to inhale 8% oxygen-air （2.0 3.0 L/min） for 2 hours to develop hypoxic-ischemic encephalopathy. Immediately after lesion, rats in the gastrodin and Danshen-treated groups were intraperitoneally injected with l g gastrodin （10 mL/kg） and 15 g Danshen （l 5 mL/kg）, respectively. MAIN OUTCOME MEASURES： Forty-eight hours after lesion, the left brain hemisphere was removed and homogenized to test the levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a by radioimmunoassay. RESULTS： Forty successfully lesioned neonatal rats from the model, gastrodin-treated, and Danshen-treated groups, and ten rats from the control group, were included in the final analysis. Levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a in brain tissue of neonatal rats were significantly higher in the model group than in the control group （both P 〈 0.01）. Levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a were significantly lower in the gastrodin-treated and the Danshen-treated groups compared to the model group （all P 〈 0.01）. However, there were no significant differences in levels of prostaglandin B2 and 6-keto-prostaglandin F 1 a between the gastrodin-treated and the Danshen-treated groups （P 〉 0.05）. CONCLUSION： Gastrodin decreased prostaglandin and thromboxan levels in neonatal rat brains subjected to hypoxia-ischemia.
文摘LightGBM is an open-source, distributed and high-performance GB framework built by Microsoft company. LightGBM has some advantages such as fast learning speed, high parallelism efficiency and high-volume data, and so on. Based on the open data set of credit card in Taiwan, five data mining methods, Logistic regression, SVM, neural network, Xgboost and LightGBM, are compared in this paper. The results show that the AUC, F1-Score and the predictive correct ratio of LightGBM are the best, and that of Xgboost is second. It indicates that LightGBM or Xgboost has a good performance in the prediction of categorical response variables and has a good application value in the big data era.
文摘A model-independent 3-D texture synthesis of physical and stochastic algorithms,based on an amplitude modulation method,is presented to realize 3-D fabric dynamic simulation.The physical functions are built to simulate fabric basic deformation.The stochastic functions,generated by Perlin noise,are used to simulate fabric natural motion in the wind.The two kinds of functions are synthesized by method of amplitude modulation.As the arithmetic uses stochastic functions in stead of recursive algorithm,it is capable of simulating the fabric material,the wind force and direction in real-time.Given the fabric material and wind strength,the stochastic functions can be created to simulate fabric motion in the wind and this model can be adjusted by controlling some certain parameters to achieve a good simulation effect.This method is conceptually intuitive,computationally fast and efficient.Furthermore,the combination of fabric physical and statistic motion characteristics provides an attractive way to improve the display effect and rate.
