AIM: To analyze the clinical risk factors for early variceal rebleeding after endoscopic variceal ligation (EVL).METHODS: 342 cirrhotic patients with esophageal varices who received elective EVL to prevent bleeding or...AIM: To analyze the clinical risk factors for early variceal rebleeding after endoscopic variceal ligation (EVL).METHODS: 342 cirrhotic patients with esophageal varices who received elective EVL to prevent bleeding or rebleeding at our endoscopy center between January 2005 and July 2010.were included in this study.The early rebleeding cases after EVL were confirmed by clinical signs or endoscopy.A case-control study was performed comparing the patients presenting with early rebleeding with those without this complication.RESULTS: The incidence of early rebleeding after EVL was 7.60%,and the morbidity of rebleeding was 26.9%.Stepwise multivariate logistic regression analysis showed that four variables were independent risk factors for early rebleeding: moderate to excessive ascites [odds ratio (OR) 62.83,95% CI: 9.39-420.56,P < 0.001],the number of bands placed (OR 17.36,95% CI: 4.00-75.34,P < 0.001),the extent of varices (OR 15.41,95% CI: 2.84-83.52,P = 0.002) and prothrombin time (PT) > 18 s (OR 11.35,95% CI: 1.93-66.70,P = 0.007).CONCLUSION: The early rebleeding rate after EVL is mainly affected by the volume of ascites,number of rubber bands used to ligate,severity of varices and prolonged PT.Effective measures for prevention and treatment should be adopted before and after EVL.展开更多
As the representative of mature investors, security analysts＇ recommendations are guidance for most investors, However, a great deal of studies nearly draws the consistent conclusion, i.e. they are not as smart as we...As the representative of mature investors, security analysts＇ recommendations are guidance for most investors, However, a great deal of studies nearly draws the consistent conclusion, i.e. they are not as smart as we imagine, or the market doesn＇t trust their recommendations so much. The existence of optimistic bias in their recommendations has been supported by empirical data widely. Hence these make many papers to explore the reasons and try to give theoretical explanations. Based on prior researches, this paper mainly compares two theoretical models both based on mathematical methods.展开更多
It is recognised that the blockage of culverts by woody debris can result in an increased risk of infrastructure damage and flooding.To date,debris transport analysis has focused on regional fluvial systems and large ...It is recognised that the blockage of culverts by woody debris can result in an increased risk of infrastructure damage and flooding.To date,debris transport analysis has focused on regional fluvial systems and large woody debris,both in flume and field experiments.Given the social and economic risk associated with urban flooding,and as urban drainage design shifts away from subsurface piped network reliance,there is an increasing need to understand debris movement in urban watercourses.The prediction of urban watercourse small woody debris(SWD)movement,both quantity and risk,has undergone only limited analysis predominantly due to lack of field data.This paper describes the development of a methodology to enable the collection of accurate and meaningful SWD residency and transportation data from watercourses.The presented research examines the limitations and effective function of PIT tag technology to collect SWD transport data in the field appropriate for risk and prediction analysis.Passive integrated transponder(PIT)technology provides a method to collect debris transport data within the urban environment.In this study,the tags are installed within small woody debris and released at known locations into a small urban natural watercourse enabling monitoring of movement and travel time.SWD velocity and detention are collated with solute time of travel,watercourse and point flow characteristics to identify the relationships between these key variables.The work presented tests three hypotheses:firstly,that the potential for unobstructed or un-detained SWD movement increases with flow velocity and water level.Secondly,that SWD travel distance,and the resistance forces along this travel path,influence SWD transport potential.Thirdly,the relationship between SWD and channel dimensions is examined with the aim of advancing representative debris transport prediction modelling.展开更多
In order to improve the precision of personal credit risk assessment, applying rough set and neural network to the credit risk scoring prediction problem in an attempt to suggest a new model with better classification...In order to improve the precision of personal credit risk assessment, applying rough set and neural network to the credit risk scoring prediction problem in an attempt to suggest a new model with better classification accuracy. To evaluate the prediction accuracy of the model, we compare its performance with those of SVM, linear discriminate analysis, logistic regression analysis, K-nearest neighbors, classification and regression tree, neural network and PCA-NN. The experimental results show the model have a very good prediction accuracy展开更多
文摘AIM: To analyze the clinical risk factors for early variceal rebleeding after endoscopic variceal ligation (EVL).METHODS: 342 cirrhotic patients with esophageal varices who received elective EVL to prevent bleeding or rebleeding at our endoscopy center between January 2005 and July 2010.were included in this study.The early rebleeding cases after EVL were confirmed by clinical signs or endoscopy.A case-control study was performed comparing the patients presenting with early rebleeding with those without this complication.RESULTS: The incidence of early rebleeding after EVL was 7.60%,and the morbidity of rebleeding was 26.9%.Stepwise multivariate logistic regression analysis showed that four variables were independent risk factors for early rebleeding: moderate to excessive ascites [odds ratio (OR) 62.83,95% CI: 9.39-420.56,P < 0.001],the number of bands placed (OR 17.36,95% CI: 4.00-75.34,P < 0.001),the extent of varices (OR 15.41,95% CI: 2.84-83.52,P = 0.002) and prothrombin time (PT) > 18 s (OR 11.35,95% CI: 1.93-66.70,P = 0.007).CONCLUSION: The early rebleeding rate after EVL is mainly affected by the volume of ascites,number of rubber bands used to ligate,severity of varices and prolonged PT.Effective measures for prevention and treatment should be adopted before and after EVL.
文摘As the representative of mature investors, security analysts＇ recommendations are guidance for most investors, However, a great deal of studies nearly draws the consistent conclusion, i.e. they are not as smart as we imagine, or the market doesn＇t trust their recommendations so much. The existence of optimistic bias in their recommendations has been supported by empirical data widely. Hence these make many papers to explore the reasons and try to give theoretical explanations. Based on prior researches, this paper mainly compares two theoretical models both based on mathematical methods.
基金supported by the Engineering and Physical Sciences Research Council(Grant Nos.EPSRC EP/J501335/1 and EP/K50337X/1)the Heriot-Watt University School of the Built Environment
文摘It is recognised that the blockage of culverts by woody debris can result in an increased risk of infrastructure damage and flooding.To date,debris transport analysis has focused on regional fluvial systems and large woody debris,both in flume and field experiments.Given the social and economic risk associated with urban flooding,and as urban drainage design shifts away from subsurface piped network reliance,there is an increasing need to understand debris movement in urban watercourses.The prediction of urban watercourse small woody debris(SWD)movement,both quantity and risk,has undergone only limited analysis predominantly due to lack of field data.This paper describes the development of a methodology to enable the collection of accurate and meaningful SWD residency and transportation data from watercourses.The presented research examines the limitations and effective function of PIT tag technology to collect SWD transport data in the field appropriate for risk and prediction analysis.Passive integrated transponder(PIT)technology provides a method to collect debris transport data within the urban environment.In this study,the tags are installed within small woody debris and released at known locations into a small urban natural watercourse enabling monitoring of movement and travel time.SWD velocity and detention are collated with solute time of travel,watercourse and point flow characteristics to identify the relationships between these key variables.The work presented tests three hypotheses:firstly,that the potential for unobstructed or un-detained SWD movement increases with flow velocity and water level.Secondly,that SWD travel distance,and the resistance forces along this travel path,influence SWD transport potential.Thirdly,the relationship between SWD and channel dimensions is examined with the aim of advancing representative debris transport prediction modelling.
文摘In order to improve the precision of personal credit risk assessment, applying rough set and neural network to the credit risk scoring prediction problem in an attempt to suggest a new model with better classification accuracy. To evaluate the prediction accuracy of the model, we compare its performance with those of SVM, linear discriminate analysis, logistic regression analysis, K-nearest neighbors, classification and regression tree, neural network and PCA-NN. The experimental results show the model have a very good prediction accuracy
