Secret sharing(SS)is part of the essential techniques in cryptography but still faces many challenges in efficiency and security.Currently,SS schemes based on the Chinese Remainder Theorem(CRT)are either low in the in...Secret sharing(SS)is part of the essential techniques in cryptography but still faces many challenges in efficiency and security.Currently,SS schemes based on the Chinese Remainder Theorem(CRT)are either low in the information rate or complicated in construction.To solve the above problems,1)a simple construction of an ideal(t,n)-SS scheme is proposed based on CRT for a polynomial ring.Compared with Ning’s scheme,it is much more efficient in generating n pairwise coprime modular polynomials during the scheme construction phase.Moreover,Shamir’s scheme is also a special case of our scheme.To further improve the security,2)a common-factor-based(t,n)-SS scheme is proposed in which all shareholders share a common polynomial factor.It enables both the verification of received shares and the establishment of a secure channel among shareholders during the reconstruction phase.As a result,the scheme is resistant to eavesdropping and modification attacks by outside adversaries.展开更多
BACKGROUND Previous studies have revealed that patients with asymptomatic common bile duct(CBD)stones are at a high risk of developing post-endoscopic retrograde cholangiopancreatography(ERCP)pancreatitis(PEP).However...BACKGROUND Previous studies have revealed that patients with asymptomatic common bile duct(CBD)stones are at a high risk of developing post-endoscopic retrograde cholangiopancreatography(ERCP)pancreatitis(PEP).However,no studies to date have addressed the risk factors for PEP in patients with asymptomatic CBD stones.AIM To examine the risk factors for PEP in patients with asymptomatic CBD stones.METHODS Using medical records of three institutions in Japan for 6 years,we identified a total of 1135 patients with choledocholithiasis including 967 symptomatic patients and 168 asymptomatic patients with native papilla who underwent therapeutic ERCP.We performed univariate and multivariate analyses to examine the risk factors for PEP in the 168 patients with asymptomatic CBD stones.RESULTS The overall incidence rate of PEP in all the patients with during study period was 4.7%(53/1135).Of the 168 patients with asymptomatic CBD stones,24(14.3%)developed PEP.In univariate analysis,precut sphincterotomy(P=0.009)and biliary balloon sphincter dilation(P=0.043)were significant risk factors for PEP.In multivariate analysis,precut sphincterotomy(P=0.002,95%CI:2.2-27.8,odds ratio=7.7),biliary balloon sphincter dilation(P=0.015,95%CI:1.4-17.3,odds ratio=4.9),and trainee endoscopists(P=0.048,95%CI:1.01-8.1,odds ratio=2.9)were significant risk factors for PEP.CONCLUSION ERCP for asymptomatic CBD stones should be performed by experienced endoscopists.When performing precut sphincterotomy or biliary balloon sphincter dilation in patients with asymptomatic CBD stones,the placement of a prophylactic pancreatic stent is strongly recommended to prevent PEP.展开更多
BACKGROUND Post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP)is a critical and poorly managed complication of ERCP. Endoscopists need to understand the risk factors for PEP. However, the major...BACKGROUND Post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP)is a critical and poorly managed complication of ERCP. Endoscopists need to understand the risk factors for PEP. However, the majority of studies investigating ERCP-related risk factors have included well-trained endoscopists,with the issue of endoscopist experience on PEP incidence not having been systematically evaluated.AIM To explore the risk factors for PEP in beginner endoscopists without supervision.METHODS We performed a retrospective analysis of 293 patients, with na?ve papilla and no history of pancreatitis, treated using bile duct cannulation. Patients were classified according to the endoscopist’s experience(beginner vs expert). The angle of the distal common bile duct(CBD) was measured as the angle between the lower wall of the bile duct and a vertical line extending to the lower wall of the bile duct on coronal view computed tomography.RESULTS After propensity matching, there were no differences between patients treated by the expert and beginner endoscopist with regard to age, sex, mean bile duct dilatation, and ratio of benign disease. The distal CBD angle was classified as acute(> 30o) or obtuse(≤ 30o), based on the mean angle of 29.9o for the group. An acute distal CBD angle was a significant risk factor for PEP for beginner(P =0.049), but not expert.CONCLUSION For beginner endoscopists first performing unsupervised ERCP, cases with an obtuse distal CBD angle may be more appropriate to lower the risk of PEP.展开更多
This study investigates the degree of capital mobility in a panel of 16 Latin American and 4 Caribbean countries during 1960 to 2017 against the backdrop of the Feldstein-Horioka hypothesis by applying recent panel da...This study investigates the degree of capital mobility in a panel of 16 Latin American and 4 Caribbean countries during 1960 to 2017 against the backdrop of the Feldstein-Horioka hypothesis by applying recent panel data techniques.This is the first study on capital mobility in Latin American and Caribbean countries to employ the recently developed panel data procedure of the dynamic common correlated effects modeling technique of Chudik and Pesaran(J Econ 188:393–420,2015)and the error-correction testing of Gengenbach,Urbain,and Westerlund(Panel error correction testing with global stochastic trends,2008,J Appl Econ 31:982–1004,2016).These approaches address the serious panel data econometric issues of crosssection dependence,slope heterogeneity,nonstationarity,and endogeneity in a multifactor error-structure framework.The empirical findings of this study reveal a low average(mean)savings–retention coefficient for the panel as a whole and for most individual countries,as well as indicating a cointegration relationship between saving and investment ratios.The results indicate that there is a relatively high degree of capital mobility in the Latin American and Caribbean countries in the short run,while the long-run solvency condition is maintained,which is due to reduced frictions in goods and services markets causing increase competition.Increased capital mobility in these countries can promote economic growth and hasten the process of globalization by creating a conducive economic environment for FDI in these countries.展开更多
目的分析基于Clavien-Dindo分级的腹腔镜胆总管探查术(laparoscopic common bile duct exploration,LCBDE)术后并发症的相关因素,构建对应的预测模型并验证其效能。方法采用前瞻性研究,选取2023年1月至2025年5月于太仓市第一人民医院行L...目的分析基于Clavien-Dindo分级的腹腔镜胆总管探查术(laparoscopic common bile duct exploration,LCBDE)术后并发症的相关因素,构建对应的预测模型并验证其效能。方法采用前瞻性研究,选取2023年1月至2025年5月于太仓市第一人民医院行LCBDE的病人285例,以2∶1随机分为训练集、验证集,分别190例、95例。随访统计病人术后并发症Clavien-Dindo分级,将训练集病人中发生Clavien-Dindo分级≥Ⅱ级并发症者分为并发症≥Ⅱ级组,无并发症及Clavien-Dindo分级Ⅰ级并发症者分为并发症0~Ⅰ级组。比较两组一般资料,经多因素logistic回归模型分析ClavienDindo分级≥Ⅱ级并发症的影响因素,建立对应的预测模型,采用受试者操作特征(ROC)曲线、校正曲线验证其效能及区分度。结果并发症≥Ⅱ级组26例,并发症0~Ⅰ级组164例,并发症≥Ⅱ级组美国麻醉医师协会(ASA)分级≥Ⅲ级构成比、合并中/重度急性胆管炎构成比、查尔森合并症指数(Charlson comorbidity index,CCI)、术中出血量均高于并发症0~Ⅰ级组(均P<0.05),白蛋白水平低于并发症0~Ⅰ级组(P<0.05)。多因素logistic回归模型显示,以下因素是LCBDE术后发生Clavien-Dindo分级≥Ⅱ级并发症的危险因素:ASA分级≥Ⅲ级(OR=3.550,95%CI:1.271~9.915),CCI评分(OR=2.617,95%CI:1.151~5.949),合并中/重度急性胆管炎(OR=2.171,95%CI:1.296~3.635),术中出血量(OR=2.872,95%CI:1.322~6.241),均P<0.05;白蛋白(OR=0.426,95%CI:0.200~0.904)是保护因素(P<0.05);建立logistic回归方程:Logit函数=–12.874–0.854X1(白蛋白)+1.267X2(ASA分级≥Ⅲ级)+0.962X3(CCI评分)+0.775X4(合并中/重度急性胆管炎)+1.055X5(术中出血量)。ROC曲线显示,该模型预测训练集术后发生Clavien-Dindo分级≥Ⅱ级并发症的曲线下面积(AUC)为0.929,敏感度为84.62%,特异度为98.17%,预测验证集术后发生Clavien-Dindo分级≥Ⅱ级并发症的AUC为0.920,敏感度为92.31%,特异度为81.71%。HosmerLemeshow检验显示,该预测模型预测训练集、验证集病人术后发生Clavien-Dindo分级≥Ⅱ级并发症的概率与实际概率比较,差异均无统计学意义(训练集:χ^(2)=6.036,P=0.702;验证集:χ^(2)=7.254,P=0.512)。结论ASA分级≥Ⅲ级、CCI评分、合并中/重度急性胆管炎、术中出血量是LCBDE术后发生Clavien-Dindo分级≥Ⅱ级并发症的危险因素,白蛋白是保护因素,对应的预测模型经验证具有良好的预测效能。展开更多
In the paper, a general framework for large scale modeling of macroeconomic and financial time series is introduced. The proposed approach is characterized by simplicity of implementation, performing well independentl...In the paper, a general framework for large scale modeling of macroeconomic and financial time series is introduced. The proposed approach is characterized by simplicity of implementation, performing well independently of persistence and heteroskedasticity properties, accounting for common deterministic and stochastic factors. Monte Carlo results strongly support the proposed methodology, validating its use also for relatively small cross-sectional and temporal samples.展开更多
Suture and autologous nerve transplantation are the primary therapeutic measures for completely severed nerves. However, imbalances in the microenvironment and adhesion of surrounding tissues can affect the quality of...Suture and autologous nerve transplantation are the primary therapeutic measures for completely severed nerves. However, imbalances in the microenvironment and adhesion of surrounding tissues can affect the quality of nerve regeneration and repair. Previous studies have shown that human amniotic membrane can promote the healing of a variety of tissues. In this study, the right common peroneal nerve underwent a 5-mm transection in rats. Epineural nerve repair was performed using 10/0 non-absorbable surgical suture. The repair site was wrapped with a two-layer amniotic membrane with α-cyanoacrylate rapid medical adhesive after suture. Hindlimb motor function was assessed using footprint analysis. Conduction velocity of the common peroneal nerve was calculated by neural electrical stimulation. The retrograde axoplasmic transport of the common peroneal nerve was observed using fast blue BB salt retrograde fluorescent staining. Hematoxylin- eosin staining was used to detect the pathological changes of the common peroneal nerve sputum. The mRNA expression of axon regeneration-related neurotrophic factors and inhibitors was measured using real-time polymerase chain reaction. The results showed that the amniotic membrane significantly improved the function of the injured nerve;the toe spread function rapidly recovered, the nerve conduction velocity was restored, and the number of fast blue BB salt particles were increased in the spinal cord. The amniotic membrane also increased the recovery rate of the tibialis anterior muscle and improved the tissue structure of the muscle. Meanwhile, mRNA expression of nerve growth factor, growth associated protein-43, collapsin response mediator protein-2, and brain-derived neurotrophic factor recovered to near-normal levels, while Lingo-1 mRNA expression decreased significantly in spinal cord tissues. mRNA expression of glial-derived neurotrophic factor did not change significantly. Changes in mRNA levels were more significant in amniotic-membrane-wrapping-treated rats compared with model and nerve sutured rats. These results demonstrate that fresh amniotic membrane wrapping can promote the functional recovery of sutured common peroneal nerve via regulation of expression levels of neurotrophic factors and inhibitors associated with axonal regeneration. The study was approved by the Committee on Animal Research and Ethics at the Affiliate Hospital of Zunyi Medical University, China (approval No. 112) on December 1, 2017.展开更多
基金This work was supported by National Key R&D Project 2018YFB2100300the National Natural Science Foundation of China(Grant No.61520106007).
文摘Secret sharing(SS)is part of the essential techniques in cryptography but still faces many challenges in efficiency and security.Currently,SS schemes based on the Chinese Remainder Theorem(CRT)are either low in the information rate or complicated in construction.To solve the above problems,1)a simple construction of an ideal(t,n)-SS scheme is proposed based on CRT for a polynomial ring.Compared with Ning’s scheme,it is much more efficient in generating n pairwise coprime modular polynomials during the scheme construction phase.Moreover,Shamir’s scheme is also a special case of our scheme.To further improve the security,2)a common-factor-based(t,n)-SS scheme is proposed in which all shareholders share a common polynomial factor.It enables both the verification of received shares and the establishment of a secure channel among shareholders during the reconstruction phase.As a result,the scheme is resistant to eavesdropping and modification attacks by outside adversaries.
文摘BACKGROUND Previous studies have revealed that patients with asymptomatic common bile duct(CBD)stones are at a high risk of developing post-endoscopic retrograde cholangiopancreatography(ERCP)pancreatitis(PEP).However,no studies to date have addressed the risk factors for PEP in patients with asymptomatic CBD stones.AIM To examine the risk factors for PEP in patients with asymptomatic CBD stones.METHODS Using medical records of three institutions in Japan for 6 years,we identified a total of 1135 patients with choledocholithiasis including 967 symptomatic patients and 168 asymptomatic patients with native papilla who underwent therapeutic ERCP.We performed univariate and multivariate analyses to examine the risk factors for PEP in the 168 patients with asymptomatic CBD stones.RESULTS The overall incidence rate of PEP in all the patients with during study period was 4.7%(53/1135).Of the 168 patients with asymptomatic CBD stones,24(14.3%)developed PEP.In univariate analysis,precut sphincterotomy(P=0.009)and biliary balloon sphincter dilation(P=0.043)were significant risk factors for PEP.In multivariate analysis,precut sphincterotomy(P=0.002,95%CI:2.2-27.8,odds ratio=7.7),biliary balloon sphincter dilation(P=0.015,95%CI:1.4-17.3,odds ratio=4.9),and trainee endoscopists(P=0.048,95%CI:1.01-8.1,odds ratio=2.9)were significant risk factors for PEP.CONCLUSION ERCP for asymptomatic CBD stones should be performed by experienced endoscopists.When performing precut sphincterotomy or biliary balloon sphincter dilation in patients with asymptomatic CBD stones,the placement of a prophylactic pancreatic stent is strongly recommended to prevent PEP.
基金Supported by Biomedical Research Institute Grant,No.2019B021,Pusan National University Hospital
文摘BACKGROUND Post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP)is a critical and poorly managed complication of ERCP. Endoscopists need to understand the risk factors for PEP. However, the majority of studies investigating ERCP-related risk factors have included well-trained endoscopists,with the issue of endoscopist experience on PEP incidence not having been systematically evaluated.AIM To explore the risk factors for PEP in beginner endoscopists without supervision.METHODS We performed a retrospective analysis of 293 patients, with na?ve papilla and no history of pancreatitis, treated using bile duct cannulation. Patients were classified according to the endoscopist’s experience(beginner vs expert). The angle of the distal common bile duct(CBD) was measured as the angle between the lower wall of the bile duct and a vertical line extending to the lower wall of the bile duct on coronal view computed tomography.RESULTS After propensity matching, there were no differences between patients treated by the expert and beginner endoscopist with regard to age, sex, mean bile duct dilatation, and ratio of benign disease. The distal CBD angle was classified as acute(> 30o) or obtuse(≤ 30o), based on the mean angle of 29.9o for the group. An acute distal CBD angle was a significant risk factor for PEP for beginner(P =0.049), but not expert.CONCLUSION For beginner endoscopists first performing unsupervised ERCP, cases with an obtuse distal CBD angle may be more appropriate to lower the risk of PEP.
文摘This study investigates the degree of capital mobility in a panel of 16 Latin American and 4 Caribbean countries during 1960 to 2017 against the backdrop of the Feldstein-Horioka hypothesis by applying recent panel data techniques.This is the first study on capital mobility in Latin American and Caribbean countries to employ the recently developed panel data procedure of the dynamic common correlated effects modeling technique of Chudik and Pesaran(J Econ 188:393–420,2015)and the error-correction testing of Gengenbach,Urbain,and Westerlund(Panel error correction testing with global stochastic trends,2008,J Appl Econ 31:982–1004,2016).These approaches address the serious panel data econometric issues of crosssection dependence,slope heterogeneity,nonstationarity,and endogeneity in a multifactor error-structure framework.The empirical findings of this study reveal a low average(mean)savings–retention coefficient for the panel as a whole and for most individual countries,as well as indicating a cointegration relationship between saving and investment ratios.The results indicate that there is a relatively high degree of capital mobility in the Latin American and Caribbean countries in the short run,while the long-run solvency condition is maintained,which is due to reduced frictions in goods and services markets causing increase competition.Increased capital mobility in these countries can promote economic growth and hasten the process of globalization by creating a conducive economic environment for FDI in these countries.
文摘目的分析基于Clavien-Dindo分级的腹腔镜胆总管探查术(laparoscopic common bile duct exploration,LCBDE)术后并发症的相关因素,构建对应的预测模型并验证其效能。方法采用前瞻性研究,选取2023年1月至2025年5月于太仓市第一人民医院行LCBDE的病人285例,以2∶1随机分为训练集、验证集,分别190例、95例。随访统计病人术后并发症Clavien-Dindo分级,将训练集病人中发生Clavien-Dindo分级≥Ⅱ级并发症者分为并发症≥Ⅱ级组,无并发症及Clavien-Dindo分级Ⅰ级并发症者分为并发症0~Ⅰ级组。比较两组一般资料,经多因素logistic回归模型分析ClavienDindo分级≥Ⅱ级并发症的影响因素,建立对应的预测模型,采用受试者操作特征(ROC)曲线、校正曲线验证其效能及区分度。结果并发症≥Ⅱ级组26例,并发症0~Ⅰ级组164例,并发症≥Ⅱ级组美国麻醉医师协会(ASA)分级≥Ⅲ级构成比、合并中/重度急性胆管炎构成比、查尔森合并症指数(Charlson comorbidity index,CCI)、术中出血量均高于并发症0~Ⅰ级组(均P<0.05),白蛋白水平低于并发症0~Ⅰ级组(P<0.05)。多因素logistic回归模型显示,以下因素是LCBDE术后发生Clavien-Dindo分级≥Ⅱ级并发症的危险因素:ASA分级≥Ⅲ级(OR=3.550,95%CI:1.271~9.915),CCI评分(OR=2.617,95%CI:1.151~5.949),合并中/重度急性胆管炎(OR=2.171,95%CI:1.296~3.635),术中出血量(OR=2.872,95%CI:1.322~6.241),均P<0.05;白蛋白(OR=0.426,95%CI:0.200~0.904)是保护因素(P<0.05);建立logistic回归方程:Logit函数=–12.874–0.854X1(白蛋白)+1.267X2(ASA分级≥Ⅲ级)+0.962X3(CCI评分)+0.775X4(合并中/重度急性胆管炎)+1.055X5(术中出血量)。ROC曲线显示,该模型预测训练集术后发生Clavien-Dindo分级≥Ⅱ级并发症的曲线下面积(AUC)为0.929,敏感度为84.62%,特异度为98.17%,预测验证集术后发生Clavien-Dindo分级≥Ⅱ级并发症的AUC为0.920,敏感度为92.31%,特异度为81.71%。HosmerLemeshow检验显示,该预测模型预测训练集、验证集病人术后发生Clavien-Dindo分级≥Ⅱ级并发症的概率与实际概率比较,差异均无统计学意义(训练集:χ^(2)=6.036,P=0.702;验证集:χ^(2)=7.254,P=0.512)。结论ASA分级≥Ⅲ级、CCI评分、合并中/重度急性胆管炎、术中出血量是LCBDE术后发生Clavien-Dindo分级≥Ⅱ级并发症的危险因素,白蛋白是保护因素,对应的预测模型经验证具有良好的预测效能。
文摘In the paper, a general framework for large scale modeling of macroeconomic and financial time series is introduced. The proposed approach is characterized by simplicity of implementation, performing well independently of persistence and heteroskedasticity properties, accounting for common deterministic and stochastic factors. Monte Carlo results strongly support the proposed methodology, validating its use also for relatively small cross-sectional and temporal samples.
基金supported by Guizhou Province Major Special Projects in Science and Technology of China,No.Qin Ke He Zhong Da Zhuan Xiang Zi [2011]6002the Special Co-operation Funds of the Science and Technology Administration in Provinces and Cities of China,No.Sheng Shi He(2014)59(both to LMY)
文摘Suture and autologous nerve transplantation are the primary therapeutic measures for completely severed nerves. However, imbalances in the microenvironment and adhesion of surrounding tissues can affect the quality of nerve regeneration and repair. Previous studies have shown that human amniotic membrane can promote the healing of a variety of tissues. In this study, the right common peroneal nerve underwent a 5-mm transection in rats. Epineural nerve repair was performed using 10/0 non-absorbable surgical suture. The repair site was wrapped with a two-layer amniotic membrane with α-cyanoacrylate rapid medical adhesive after suture. Hindlimb motor function was assessed using footprint analysis. Conduction velocity of the common peroneal nerve was calculated by neural electrical stimulation. The retrograde axoplasmic transport of the common peroneal nerve was observed using fast blue BB salt retrograde fluorescent staining. Hematoxylin- eosin staining was used to detect the pathological changes of the common peroneal nerve sputum. The mRNA expression of axon regeneration-related neurotrophic factors and inhibitors was measured using real-time polymerase chain reaction. The results showed that the amniotic membrane significantly improved the function of the injured nerve;the toe spread function rapidly recovered, the nerve conduction velocity was restored, and the number of fast blue BB salt particles were increased in the spinal cord. The amniotic membrane also increased the recovery rate of the tibialis anterior muscle and improved the tissue structure of the muscle. Meanwhile, mRNA expression of nerve growth factor, growth associated protein-43, collapsin response mediator protein-2, and brain-derived neurotrophic factor recovered to near-normal levels, while Lingo-1 mRNA expression decreased significantly in spinal cord tissues. mRNA expression of glial-derived neurotrophic factor did not change significantly. Changes in mRNA levels were more significant in amniotic-membrane-wrapping-treated rats compared with model and nerve sutured rats. These results demonstrate that fresh amniotic membrane wrapping can promote the functional recovery of sutured common peroneal nerve via regulation of expression levels of neurotrophic factors and inhibitors associated with axonal regeneration. The study was approved by the Committee on Animal Research and Ethics at the Affiliate Hospital of Zunyi Medical University, China (approval No. 112) on December 1, 2017.
