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Risk factors of recurrent choledocholithiasis following therapeutic endoscopic retrograde cholangiopancreatography 被引量:3
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作者 Lin Li Jing Wang +1 位作者 Cheng-Cheng Tong Chi-Yi He 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第3期282-287,共6页
Background:The risk factors for the recurrent choledocholithiasis after endoscopic retrograde cholangiopancreatography(ERCP)have not been well studied.The aim of this study was to explore the risk factors of recurrent... Background:The risk factors for the recurrent choledocholithiasis after endoscopic retrograde cholangiopancreatography(ERCP)have not been well studied.The aim of this study was to explore the risk factors of recurrent choledocholithiasis.Methods:We carried out a retrospective analysis of data collected between January 1,2010 and January 1,2020.Univariate analysis and multivariate analysis were used to explore the independent risk factors of recurrent choledocholithiasis following therapeutic ERCP.Results:In total,598 patients were eventually selected for analysis,299 patients in the recurrent choledocholithiasis group and 299 patients in the control group.The overall rate of recurrent choledocholithiasis was 6.91%.Multivariate analysis showed that diabetes[odds ratio(OR)=3.677,95%confidence interval(CI):1.875-7.209;P<0.001],fatty liver(OR=4.741,95%CI:1.205-18.653;P=0.026),liver cirrhosis(OR=3.900,95%CI:1.358-11.201;P=0.011),history of smoking(OR=3.773,95%CI:2.060-6.908;P<0.001),intrahepatic bile duct stone(OR=4.208,95%CI:2.220-7.976;P<0.001),biliary stent(OR=2.996,95%CI:1.870-4.800;P<0.001),and endoscopic papillary balloon dilation(EPBD)(OR=3.009,95%CI:1.921-4.715;P<0.001)were independent risk factors of recurrent choledocholithiasis.However,history of drinking(OR=0.183,95%CI:0.099-0.337;P<0.001),eating light food frequently(OR=0.511,95%CI:0.343-0.760;P=0.001),and antibiotic use before ERCP(OR=0.315,95%CI:0.200-0.497;P<0.001)were independent protective factors of recurrent choledocholithiasis.Conclusions:Patients with the abovementioned risk factors are more likely to have recurrent CBD stones.Patients who eat light food frequently and have a history of drinking are less likely to present with recurrent CBD calculi. 展开更多
关键词 RECURRENCE choledocholithiasis Endoscopic retrograde CHOLANGIOPANCREATOGRAPHY
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Recurrence of choledocholithiasis following endoscopic bile duct clearance: Long term results and factors associated with recurrent bile duct stones 被引量:48
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作者 Christos Konstantakis Christos Triantos +4 位作者 Vasileios Theopistos Georgios Theocharis Ioannis Maroulis Georgia Diamantopoulou Konstantinos Thomopoulos 《World Journal of Gastrointestinal Endoscopy》 CAS 2017年第1期26-33,共8页
AIM To evaluate the rate of recurrence of symptomatic chol-edocholithiasis and identify factors associated with the recurrence of bile duct stones in patients who underwent endoscopic retrograde cholangiopancreatograp... AIM To evaluate the rate of recurrence of symptomatic chol-edocholithiasis and identify factors associated with the recurrence of bile duct stones in patients who underwent endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic sphincterotomy(EST) for bile duct stone disease.METHODS All patients who underwent ERCP and EST for bile duct stone disease and had their bile duct cleared from 1/1/2005 until 31/12/2008 was enrolled. All symptomatic recurrences during the study period(until 31/12/2015) were recorded. Clinical and laboratory data potentially associated with common bile duct(CBD) stone recurrence were retrospectively retrieved from patients' files.RESULTS A total of 495 patients were included. Sixty seven(67) out of 495 patients(13.5%) presented with recurrent symptomatic choledocholithiasis after 35.28 ± 16.9 mo while twenty two(22) of these patients(32.8%) experienced a second recurrence after 35.19 ± 23.2 mo. Factors associated with recurrence were size(diameter) of the largest CBD stone found at first presentation(10.2 ± 6.9 mm vs 7.2 ± 4.1 mm, P = 0.024), diameter of the CBD at the first examination(15.5 ± 6.3 mm vs 12.0 ± 4.6 mm, P = 0.005), use of mechanical lithotripsy(ML)(P = 0.04) and presence of difficult lithiasis(P = 0.04). Periampullary diverticula showed a trend towards significance(P = 0.066). On the contrary, number of stones, angulation of the CBD, number of ERCP sessions required to clear the CBD at first presentation, more than one ERCP session needed to clear the bile duct initially and a gallbladder in situ did not influence recurrence. CONCLUSION Bile duct stone recurrence is a possible late complication following endoscopic stone extraction and CBD clearance. It appears to be associated with anatomical parameters(CBD diameter) and stone characteristics(stone size, use of ML, difficult lithiasis) at first presentation. 展开更多
关键词 胆汁管石头疾病 普通胆汁管作成角 choledocholithiasis 内视镜后退 cholangiopancreatography 内视镜的 sphincterotomy choledocholithiasis 的复发
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Causes associated with recurrent choledocholithiasis following therapeutic endoscopic retrograde cholangiopancreatography: A large sample sized retrospective study 被引量:29
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作者 Feng Deng Mi Zhou +4 位作者 Ping-Ping Liu Jun-Bo Hong Guo-Hua Li Xiao-Jiang Zhou You-Xiang Chen 《World Journal of Clinical Cases》 SCIE 2019年第9期1028-1037,共10页
BACKGROUND Recurrence of primary choledocholithiasis commonly occurs after complete removal of stones by therapeutic endoscopic retrograde cholangiopancreatography(ERCP). The potential causes of the recurrence of chol... BACKGROUND Recurrence of primary choledocholithiasis commonly occurs after complete removal of stones by therapeutic endoscopic retrograde cholangiopancreatography(ERCP). The potential causes of the recurrence of choledocholithiasis after ERCP are unclear.AIM To analyze the potential causes of the recurrence of choledocholithiasis after ERCP.METHODS The ERCP database of our medical center for the period between January 2007 and January 2016 was retrospectively reviewed, and information regarding eligible patients who had choledocholithiasis recurrence was collected. A 1:1 case-control study was performed for this investigation. Data including general characteristics of the patients, past medical history, ERCP-related factors,common bile duct(CBD)-related factors, laboratory indicators, and treatment was analyzed by univariate and multivariate logistic regression analysis and KaplanMeier analysisly.RESULTS First recurrence of choledocholithiasis occurred in 477 patients; among these patients, the second and several instance(≥ 3 times) recurrence rates were 19.5%and 44.07%, respectively. The average time to first choledocholithiasis recurrence was 21.65 mo. A total of 477 patients who did not have recurrence were selected as a control group. Multivariate logistic regression analysis showed that age > 65 years(odds ratio [OR] = 1.556; P = 0.018), combined history of choledocholithotomy(OR = 2.458; P < 0.01), endoscopic papillary balloon dilation(OR = 5.679; P = 0.000), endoscopic sphincterotomy(OR = 3.463; P = 0.000), CBD stent implantation(OR = 5.780; P = 0.000), multiple ERCP procedures(≥2; OR =2.75; P = 0.000), stones in the intrahepatic bile duct(OR = 2.308; P = 0.000),periampullary diverticula(OR = 1.627; P < 0.01), choledocholithiasis diameter ≥10 mm(OR = 1.599; P < 0.01), bile duct-duodenal fistula(OR = 2.69; P < 0.05),combined biliary tract infections(OR = 1.057; P < 0.01), and no preoperative antibiotic use(OR = 0.528; P < 0.01) were independent risk factors for the recurrence of choledocholithiasis after ERCP.CONCLUSION Patient age greater than 65 years is an independent risk factor for the development of recurrent choledocholithiasis following ERCP, as is history of biliary surgeries, measures during ERCP, and prevention of postoperative complications. 展开更多
关键词 choledocholithiasis Endoscopic RETROGRADE CHOLANGIOPANCREATOGRAPHY RECURRENCE Common BILE DUCT
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Microbiologic risk factors of recurrent choledocholithiasis postendoscopic sphincterotomy 被引量:5
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作者 Ying Li Wen-Hui Tan +12 位作者 Jia-Chuan Wu Zhi-Xin Huang Yan-Yan Shang Biao Liang Jian-Hui Chen Rui Pang Xin-Qiang Xie Ju-Mei Zhang Yu Ding Liang Xue Mou-Tong Chen Juan Wang Qing-Ping Wu 《World Journal of Gastroenterology》 SCIE CAS 2022年第12期1257-1271,共15页
BACKGROUND Choledocholithiasis is a severe disorder that affects a significant portion of the world’s population.Treatment using endoscopic sphincterotomy(EST)has become widespread;however,recurrence post-EST is rela... BACKGROUND Choledocholithiasis is a severe disorder that affects a significant portion of the world’s population.Treatment using endoscopic sphincterotomy(EST)has become widespread;however,recurrence post-EST is relatively common.The bile microbiome has a profound influence on the recurrence of choledocholithiasis in patients after EST;however,the key pathogens and their functions in the biliary tract remain unclear.AIM To investigate the biliary microbial characteristics of patients with recurrent choledocholithiasis post-EST,using next-generation sequencing.METHODS This cohort study included 43 patients,who presented with choledocholithiasis at the Guangdong Second Provincial General Hospital between May and June 2020.The patients had undergone EST or endoscopic papillary balloon dilation and were followed up for over a year.They were divided into either the stable or recurrent groups.We collected bile samples and extracted microbial DNA for analysis through next-generation sequencing.Resulting sequences were analyzed for core microbiome and statistical differences between the diagnosis groups;they were examined using the Kyoto Encyclopedia of Genes and Genomes pathway hierarchy level using analysis of variance.Correlation between the key genera and metabolic pathways in bile,were analyzed using Pearson’s correlation test.RESULTS The results revealed distinct clustering of biliary microbiota in recurrent choledocholithiasis.Higher relative abundances(RAs)of Fusobacterium and Neisseria(56.61%±14.81%vs 3.47%±1.10%,8.95%±3.42%vs 0.69%±0.32%,respectively)and the absence of Lactobacillus were observed in the bile of patients with recurrent disease,compared to that in stable patients.Construction of a microbiological co-occurrence network revealed a mutual relationship among Fusobacterium,Neisseria,and Leptotrichia,and an antagonistic relationship among Lactobacillales,Fusobacteriales,and Clostridiales.Functional prediction of biliary microbiome revealed that the loss of transcription and metabolic abilities may lead to recurrent choledocholithiasis.Furthermore,the prediction model based on the RA of Lactobacillales in the bile was effective in identifying the risk of recurrent choledocholithiasis(P=0.03).CONCLUSION We demonstrated differences in the bile microbiome of patients with recurrent choledocholithiasis compared to that in patients with stable disease,thereby adding to the current knowledge on its microbiologic etiology. 展开更多
关键词 choledocholithiasis Biliary tract MICROBIOME Endoscopic sphincterotomy RECURRENCE LACTOBACILLUS
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Recurrent lithiasis after surgical treatment of elderly patients with choledocholithiasis 被引量:6
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作者 Li, Zhe-Fu Chen, Xiao-Ping 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第1期67-71,共5页
BACKGROUND: The recurrence rates of choledocholithiasis depend on the type of the disease. This study was undertaken to examine recurrent lithiasis after surgical treatment of elderly patients with choledocholithiasis... BACKGROUND: The recurrence rates of choledocholithiasis depend on the type of the disease. This study was undertaken to examine recurrent lithiasis after surgical treatment of elderly patients with choledocholithiasis, especially with primary common bile duct stones, and thereby to determine the best treatment modality for choledocholithiasis in the elderly. METHODS: The recurrence rates of choledocholithiasis were calculated from the records of 193 outpatients who had been treated from January 1993 to January 2005 and monitored for periods ranging from I to 12 years (mean 6.7 years). The patients were divided into 3 groups: 81 who had undergone choledocholithotomy and T-tube drainage, 41 who had had choledochoduodenostomy. and 71 patients who had received choledochojejunostomy. RESULTS: Since the 41 choledochoduodenostomy cases had only one recurrence of choledocholithiasis, the recurrence rate was analyzed for the remaining 152 cases, which were divided into two groups: group A with recurrent lithiasis (13 cases), and group B without recurrence (139 cases). The recurrence was found in 7 patients after choledocholithotomy and T-tube drainage (7/81, 8.6%), and in 6 patients after choledochojejunostomy (6/71, 8.5%). The recurrence rates for these procedures were higher than for choledochoduodenostomy (1/41, 2.4%, P<0.05). Moreover, stones recurred in 4 of the 11 patients with primary bile duct stones who underwent choledocholithotomy an T-tube drainage (4/11, 36.4%), and in 5 of the 34 patients who had choledochojejunostomy (5/34, 14.7%). The recurrence rates for these procedures were higher than for choledochoduodenostomy (1/39, 2.6%, P<0.05). The diameter of the common bile duct was more dilated in group A (14.6 +/- 3.9 mm) than in group B (10.8 +/- 4.5 turn, P<0.05). Primary bile duct stones were found in 9 cases of group A (69.2%), and in 36 cases of group B (25.9%, P<0.01). CONCLUSION: Choledochoduodenostomy should be recommended for elderly patients with primary bile duct stones to prevent postoperative recurrent lithiasis. 展开更多
关键词 choledocholithiasis ELDERLY surgical treatment
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Ectopic opening of the common bile duct into the duodenal bulb with recurrent choledocholithiasis: A case report 被引量:1
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作者 Hao Xu Xin Li +1 位作者 Ke-Xiang Zhu Wen-Ce Zhou 《World Journal of Clinical Cases》 SCIE 2021年第19期5332-5338,共7页
BACKGROUND Ectopic opening of the common bile duct is a condition with low incidence.Patients with an ectopic common bile duct opening have a high incidence of common bile duct stones and acute cholangitis.Patients wi... BACKGROUND Ectopic opening of the common bile duct is a condition with low incidence.Patients with an ectopic common bile duct opening have a high incidence of common bile duct stones and acute cholangitis.Patients with atypical symptoms and imaging findings are easily misdiagnosed;moreover,it is difficult to retrieve stones by endoscopic retrograde cholangiopancreatography,and common bile duct stones are prone to postsurgical recurrence.CASE SUMMARY A 45-year-old male patient presented with“intermittent upper abdominal pain and elevated liver enzymes for 1 wk”.Transabdominal ultrasound indicated dilation of the common bile duct and the presence of stones.Magnetic resonance imaging showed that the common bile duct was dilated with stones and that its opening was ectopic.Endoscopic retrograde cholangiopancreatography revealed an abnormal opening of the common bile duct into the duodenal bulb and the presence of common bile duct stones.Laparoscopic extrahepatic choledochectomy and hepatoenteric anastomosis were performed.After surgery,the patient recovered well and was discharged.The patient has been followed up for 2 years since the operation.He has not experienced stone recurrence,and his liver function and quality of life are good.CONCLUSION Improved understanding of ectopic opening of the common bile duct is needed for clinicians to provide patients with appropriate treatment. 展开更多
关键词 Ectopic opening of the common bile duct choledocholithiasis CHOLANGIOJEJUNOSTOMY Treatment Laparoscopic surgery Case report
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Effect of the extrahepatic bile duct anatomy on choledocholithiasis and its clinical significance
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作者 Zheng Cao Jia Zhou +2 位作者 Li Wei Hai-Yu He Jun Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1363-1370,共8页
BACKGROUND A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde cholangiography.Anatomical irregularities within the extrahepatic ... BACKGROUND A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde cholangiography.Anatomical irregularities within the extrahepatic bile duct may increase susceptibility to bile duct stones.AIM To investigate the anatomical risk factors associated with extrahepatic bile ducts in patients diagnosed with choledocholithiasis,with a specific focus on preventing stone recurrence after surgical intervention and endoscopic lithotomy.METHODS We retrospectively analyzed the medical records of 124 patients without choledocholithiasis and 108 with confirmed choledocholithiasis who underwent magnetic resonance cholangiopancreatography examinations at our center between January 2022 and October 2022.Logistic regression analyses were conducted to identify the anatomical risk factors influencing the incidence of common bile duct stones.RESULTS Multivariate logistic regression analysis revealed that several factors independently contributed to choledocholithiasis risk.Significant independent risk factors for choledocholithiasis were diameter of the common hepatic[adjusted odds ratio(aOR)=1.43,95%confidence interval(CI):1.07-1.92,adjusted P value=0.016]and common bile(aOR=1.68,95%CI:1.27-2.23,adjusted P value<0.001)ducts,length of the common hepatic duct(aOR=0.92,95%CI:0.84-0.99,adjusted P value=0.034),and angle of the common bile duct(aOR=0.92,95%CI:0.89–0.95,adjusted P value<0.001).The anatomical features of the extrahepatic bile duct were directly associated with choledocholithiasis risk.Key risk factors include an enlarged diameter of the common hepatic and bile ducts,a shorter length of the common hepatic duct,and a reduced angle of the common bile duct. 展开更多
关键词 Bile ducts EXTRAHEPATIC choledocholithiasis CHOLANGIOPANCREATOGRAPHY Magnetic resonance CHOLANGIOPANCREATOGRAPHY Endoscopic retrograde
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Rationale of a Cross Sectional Analytic Study on Determinants of Recurrent Preeclampsia at University Clinics of Kinshasa (Democratic Republic of Congo) and at Victor Dupouy Hospital Center (France)
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作者 Mushengezi Amani Dieudonné Sengeyi Muela Andy Mbangama +4 位作者 Mokambanda Cynthia Awena Goy Sambwa Christian Kelele Nkongolo Freddy Muamba Banza Jésual Lotoy Otem Christian Ndesanzim 《Open Journal of Obstetrics and Gynecology》 2024年第5期824-831,共8页
Research Background: Pre-eclampsia is one of main causes of materno-foetal mortality and morbidity worldwide, with a prevalence of 3% - 7%. Although considered a primiparous condition, it can nevertheless recur. Sever... Research Background: Pre-eclampsia is one of main causes of materno-foetal mortality and morbidity worldwide, with a prevalence of 3% - 7%. Although considered a primiparous condition, it can nevertheless recur. Several factors appear to be associated with risk of recurrence of pre-eclampsia, such as the term of delivery of previous pregnancy, severity of disease, the existence of co-morbidities and the inter-genital space. Purpose: The aim of our study will be to analyse and identify in a population of pregnant women with a history of preeclampsia risk factors associated with occurrence of recurrent preeclampsia at University clinics of Kinshasa (Democratic Republic of Congo) and at Victor Dupouy Hospital Center (France). Methods: In this study, pregnant women with an history of preeclampsia who will give birth between November 2018 and October 2024 at University Clinics of Kinshasa (UCK) and Victor Dupouy Hospital Center (VDHC) will be included. This will be a cross-sectional analytical study, data from previous and subsequent pregnancies will be studied. Expected Result: The prevalence of recurrent preeclampsia in the study population will be determined. And we will highlight the factors that will determine the recurrence of preeclampsia by analysing the risk factors. Conclusion: Knowledge of the factors associated with recurrent preeclampsia could be an excellent tool for predicting and preventing the disease. 展开更多
关键词 recurrent Pre-Eclampsia Risk Factor Determinants
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Response letter to “Acute cholangitis: Does malignant biliary obstruction vs choledocholithiasis etiology change the outcomes?” with imaging aspects
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作者 Sonay Aydin Baris Irgul 《World Journal of Clinical Cases》 SCIE 2024年第5期1029-1032,共4页
Radiological imaging findings may contribute to the differentiation of malignant biliary obstruction from choledocholithiasis in the etiology of acute cholangitis.
关键词 Malignant biliary obstruction choledocholithiasis Acute cholangitis Dilated bile ducts Magnetic resonance cholangiopancreatography Endoscopic retrograde cholangiopancreatography
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Recurrent Transient Ischemic Attacks Revealing Cerebral Amyloid Angiopathy: A Comprehensive Case
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作者 Kenza Khelfaoui Tredano Houyam Tibar +3 位作者 Kaoutar El Alaoui Taoussi Wafae Regragui Abdeljalil El Quessar Ali Benomar 《World Journal of Neuroscience》 CAS 2024年第1期33-36,共4页
This case report investigates the manifestation of cerebral amyloid angiopathy (CAA) through recurrent Transient Ischemic Attacks (TIAs) in an 82-year-old patient. Despite initial diagnostic complexities, cerebral ang... This case report investigates the manifestation of cerebral amyloid angiopathy (CAA) through recurrent Transient Ischemic Attacks (TIAs) in an 82-year-old patient. Despite initial diagnostic complexities, cerebral angiography-MRI revealed features indicative of CAA. Symptomatic treatment resulted in improvement, but the patient later developed a fatal hematoma. The discussion navigates the intricate therapeutic landscape of repetitive TIAs in the elderly with cardiovascular risk factors, emphasizing the pivotal role of cerebral MRI and meticulous bleeding risk management. The conclusion stresses the importance of incorporating SWI sequences, specifically when suspecting a cardioembolic TIA, as a diagnostic measure to explore and exclude CAA in the differential diagnosis. This case report provides valuable insights into these challenges, highlighting the need to consider CAA in relevant cases. 展开更多
关键词 Cerebral Amyloid Angiopathy Transient Ischemic Attacks recurrent Hemiparesis Susceptibility-Weighted Imaging Cardioembolic Origin Bleeding Risk Management Differential Diagnosis
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Recurrent neural network decoding of rotated surface codes based on distributed strategy
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作者 李帆 李熬庆 +1 位作者 甘启迪 马鸿洋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期322-330,共9页
Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error corre... Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error correction using neural network-based machine learning methods is a promising approach that is adapted to physical systems without the need to build noise models.In this paper,we use a distributed decoding strategy,which effectively alleviates the problem of exponential growth of the training set required for neural networks as the code distance of quantum error-correcting codes increases.Our decoding algorithm is based on renormalization group decoding and recurrent neural network decoder.The recurrent neural network is trained through the ResNet architecture to improve its decoding accuracy.Then we test the decoding performance of our distributed strategy decoder,recurrent neural network decoder,and the classic minimum weight perfect matching(MWPM)decoder for rotated surface codes with different code distances under the circuit noise model,the thresholds of these three decoders are about 0.0052,0.0051,and 0.0049,respectively.Our results demonstrate that the distributed strategy decoder outperforms the other two decoders,achieving approximately a 5%improvement in decoding efficiency compared to the MWPM decoder and approximately a 2%improvement compared to the recurrent neural network decoder. 展开更多
关键词 quantum error correction rotated surface code recurrent neural network distributed strategy
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Recorded recurrent deep reinforcement learning guidance laws for intercepting endoatmospheric maneuvering missiles
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作者 Xiaoqi Qiu Peng Lai +1 位作者 Changsheng Gao Wuxing Jing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期457-470,共14页
This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with u... This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with uncertainties and observation noise.The attack-defense engagement scenario is modeled as a partially observable Markov decision process(POMDP).Given the benefits of recurrent neural networks(RNNs)in processing sequence information,an RNN layer is incorporated into the agent’s policy network to alleviate the bottleneck of traditional deep reinforcement learning methods while dealing with POMDPs.The measurements from the interceptor’s seeker during each guidance cycle are combined into one sequence as the input to the policy network since the detection frequency of an interceptor is usually higher than its guidance frequency.During training,the hidden states of the RNN layer in the policy network are recorded to overcome the partially observable problem that this RNN layer causes inside the agent.The training curves show that the proposed RRTD3 successfully enhances data efficiency,training speed,and training stability.The test results confirm the advantages of the RRTD3-based guidance laws over some conventional guidance laws. 展开更多
关键词 Endoatmospheric interception Missile guidance Reinforcement learning Markov decision process recurrent neural networks
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Secrecy Outage Probability Minimization in Wireless-Powered Communications Using an Improved Biogeography-Based Optimization-Inspired Recurrent Neural Network
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作者 Mohammad Mehdi Sharifi Nevisi Elnaz Bashir +3 位作者 Diego Martín Seyedkian Rezvanjou Farzaneh Shoushtari Ehsan Ghafourian 《Computers, Materials & Continua》 SCIE EI 2024年第3期3971-3991,共21页
This paper focuses on wireless-powered communication systems,which are increasingly relevant in the Internet of Things(IoT)due to their ability to extend the operational lifetime of devices with limited energy.The mai... This paper focuses on wireless-powered communication systems,which are increasingly relevant in the Internet of Things(IoT)due to their ability to extend the operational lifetime of devices with limited energy.The main contribution of the paper is a novel approach to minimize the secrecy outage probability(SOP)in these systems.Minimizing SOP is crucial for maintaining the confidentiality and integrity of data,especially in situations where the transmission of sensitive data is critical.Our proposed method harnesses the power of an improved biogeography-based optimization(IBBO)to effectively train a recurrent neural network(RNN).The proposed IBBO introduces an innovative migration model.The core advantage of IBBO lies in its adeptness at maintaining equilibrium between exploration and exploitation.This is accomplished by integrating tactics such as advancing towards a random habitat,adopting the crossover operator from genetic algorithms(GA),and utilizing the global best(Gbest)operator from particle swarm optimization(PSO)into the IBBO framework.The IBBO demonstrates its efficacy by enabling the RNN to optimize the system parameters,resulting in significant outage probability reduction.Through comprehensive simulations,we showcase the superiority of the IBBO-RNN over existing approaches,highlighting its capability to achieve remarkable gains in SOP minimization.This paper compares nine methods for predicting outage probability in wireless-powered communications.The IBBO-RNN achieved the highest accuracy rate of 98.92%,showing a significant performance improvement.In contrast,the standard RNN recorded lower accuracy rates of 91.27%.The IBBO-RNN maintains lower SOP values across the entire signal-to-noise ratio(SNR)spectrum tested,suggesting that the method is highly effective at optimizing system parameters for improved secrecy even at lower SNRs. 展开更多
关键词 Wireless-powered communications secrecy outage probability improved biogeography-based optimization recurrent neural network
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Mapping Network-Coordinated Stacked Gated Recurrent Units for Turbulence Prediction
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作者 Zhiming Zhang Shangce Gao +2 位作者 MengChu Zhou Mengtao Yan Shuyang Cao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1331-1341,共11页
Accurately predicting fluid forces acting on the sur-face of a structure is crucial in engineering design.However,this task becomes particularly challenging in turbulent flow,due to the complex and irregular changes i... Accurately predicting fluid forces acting on the sur-face of a structure is crucial in engineering design.However,this task becomes particularly challenging in turbulent flow,due to the complex and irregular changes in the flow field.In this study,we propose a novel deep learning method,named mapping net-work-coordinated stacked gated recurrent units(MSU),for pre-dicting pressure on a circular cylinder from velocity data.Specifi-cally,our coordinated learning strategy is designed to extract the most critical velocity point for prediction,a process that has not been explored before.In our experiments,MSU extracts one point from a velocity field containing 121 points and utilizes this point to accurately predict 100 pressure points on the cylinder.This method significantly reduces the workload of data measure-ment in practical engineering applications.Our experimental results demonstrate that MSU predictions are highly similar to the real turbulent data in both spatio-temporal and individual aspects.Furthermore,the comparison results show that MSU predicts more precise results,even outperforming models that use all velocity field points.Compared with state-of-the-art methods,MSU has an average improvement of more than 45%in various indicators such as root mean square error(RMSE).Through comprehensive and authoritative physical verification,we estab-lished that MSU’s prediction results closely align with pressure field data obtained in real turbulence fields.This confirmation underscores the considerable potential of MSU for practical applications in real engineering scenarios.The code is available at https://github.com/zhangzm0128/MSU. 展开更多
关键词 Convolutional neural network deep learning recurrent neural network turbulence prediction wind load predic-tion.
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Increased retinal venule diameter as a prognostic indicator for recurrent cerebrovascular events:a prospective observational study
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作者 Ying Zhao Dawei Dong +5 位作者 Ding Yan Bing Yang Weirong Gui Man Ke Anding Xu Zefeng Tan 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1156-1160,共5页
Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy populations.However,the ability of retinal vasculature changes,specifically focusing on retinal vessel diameter,t... Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy populations.However,the ability of retinal vasculature changes,specifically focusing on retinal vessel diameter,to predict the recurrence of cerebrovascular events in patients with ischemic stroke has not been determined comprehensively.While previous studies have shown a link between retinal vessel diameter and recurrent cerebrovascular events,they have not incorporated this information into a predictive model.Therefore,this study aimed to investigate the relationship between retinal vessel diameter and subsequent cerebrovascular events in patients with acute ischemic stroke.Additionally,we sought to establish a predictive model by combining retinal veessel diameter with traditional risk factors.We performed a prospective observational study of 141 patients with acute ischemic stroke who were admitted to the First Affiliated Hospital of Jinan University.All of these patients underwent digital retinal imaging within 72 hours of admission and were followed up for 3 years.We found that,after adjusting for related risk factors,patients with acute ischemic stroke with mean arteriolar diameter within 0.5-1.0 disc diameters of the disc margin(MAD_(0.5-1.0DD))of≥74.14μm and mean venular diameter within 0.5-1.0 disc diameters of the disc margin(MVD_(0.5-1.0DD))of≥83.91μm tended to experience recurrent cerebrovascular events.We established three multivariate Cox proportional hazard regression models:model 1 included traditional risk factors,model 2 added MAD_(0.5-1.0DD)to model 1,and model 3 added MVD0.5-1.0DD to model 1.Model 3 had the greatest potential to predict subsequent cerebrovascular events,followed by model 2,and finally model 1.These findings indicate that combining retinal venular or arteriolar diameter with traditional risk factors could improve the prediction of recurrent cerebrovascular events in patients with acute ischemic stroke,and that retinal imaging could be a useful and non-invasive method for identifying high-risk patients who require closer monitoring and more aggressive management. 展开更多
关键词 acute ischemic stroke arteriolar cerebrovascular events DIAMETER digital retinal imaging MICROVASCULATURE prediction recurrent RETINA venular
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Ocular rosacea without facial erythema involvement manifesting as bilateral multiple recurrent chalazions:A case report
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作者 Xue-Mei Han Yi-Mai Zhou Lu-Sha Cen 《World Journal of Clinical Cases》 SCIE 2024年第17期3253-3258,共6页
BACKGROUND In addition to the non-specific symptomatology of ocular rosacea,currently,there are no reliable diagnostic tests for the disease,which may lead to its misdiagnosis.Here,we report a case of ocular rosacea p... BACKGROUND In addition to the non-specific symptomatology of ocular rosacea,currently,there are no reliable diagnostic tests for the disease,which may lead to its misdiagnosis.Here,we report a case of ocular rosacea presenting with multiple recurrent chalazion on both eyelids.CASE SUMMARY A 63-year-old female patient presented with multiple chalazion and dry eyes in both eyes,with no facial erythema.Initial management done were application of steroid eye ointment on both eyelids,hot compresses,and eyelid margin cleaning;noting that there was no relief of symptoms.Surgical excision of the chalazion was done on both eyes,however,bilateral recurrence occurred post-operatively.The pathological studies showed infiltration of a small amount of fibrous tissue with many chronic inflammatory cells.Immunohistochemistry studies were positive for LL-37.Resolution of the chalazion occurred after oral administration of doxycycline and azithromycin.CONCLUSION Our findings show that ophthalmologists should recognize the ocular manifestations of skin diseases. 展开更多
关键词 Ocular rosacea ROSACEA recurrent chalazion Bilateral chalazion Multiple chalazion Case report
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Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles:Sequential Embryo Transfer or Double-blastocyst Transfer?
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作者 Qiao-hang ZHAO Yu-wei SONG +8 位作者 Jian CHEN Xiang ZHOU Ji-lai XIE Qiu-ping YAO Qi-yin DONG Chun FENG Li-ming ZHOU Wei-ping FU Min JIN 《Current Medical Science》 SCIE CAS 2024年第1期212-222,共11页
Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of Se... Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of SeET and DBT on pregnancy outcomes.Methods Totally,261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective analysis.According to different embryo quality and transfer strategies,they were divided into four groups:group A,good-quality SeET(GQ-SeET,n=38 cycles);group B,poor-quality or mixed-quality SeET(PQ/MQ-SeET,n=31 cycles);group C,good-quality DBT(GQ-DBT,n=121 cycles);and group D,poor-quality or mixed-quality DBT(PQ/MQ-DBT,n=71 cycles).The main outcome,clinical pregnancy rate,was compared,and the generalized estimating equation(GEE)model was used to correct potential confounders that might impact pregnancy outcomes.Results GQ-DBT achieved a significantly higher clinical pregnancy rate(aOR 2.588,95%CI 1.267–5.284,P=0.009)and live birth rate(aOR 3.082,95%CI 1.482–6.412,P=0.003)than PQ/MQ-DBT.Similarly,the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET(aOR 4.047,95%CI 1.218–13.450,P=0.023).The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT,and the same results were found between PQ/MQ-SeET and PQ/MQ-DBT.Conclusion SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two groups.Better clinical pregnancy outcomes could be obtained by transferring good-quality embryos,no matter whether in SeET or DBT.Embryo quality plays a more important role in pregnancy outcomes for RIF patients. 展开更多
关键词 recurrent implantation failure sequential embryo transfer frozen-thawed embryo transfer embryo transfer strategies
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Effects of data smoothing and recurrent neural network(RNN)algorithms for real-time forecasting of tunnel boring machine(TBM)performance
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作者 Feng Shan Xuzhen He +1 位作者 Danial Jahed Armaghani Daichao Sheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1538-1551,共14页
Tunnel boring machines(TBMs)have been widely utilised in tunnel construction due to their high efficiency and reliability.Accurately predicting TBM performance can improve project time management,cost control,and risk... Tunnel boring machines(TBMs)have been widely utilised in tunnel construction due to their high efficiency and reliability.Accurately predicting TBM performance can improve project time management,cost control,and risk management.This study aims to use deep learning to develop real-time models for predicting the penetration rate(PR).The models are built using data from the Changsha metro project,and their performances are evaluated using unseen data from the Zhengzhou Metro project.In one-step forecast,the predicted penetration rate follows the trend of the measured penetration rate in both training and testing.The autoregressive integrated moving average(ARIMA)model is compared with the recurrent neural network(RNN)model.The results show that univariate models,which only consider historical penetration rate itself,perform better than multivariate models that take into account multiple geological and operational parameters(GEO and OP).Next,an RNN variant combining time series of penetration rate with the last-step geological and operational parameters is developed,and it performs better than other models.A sensitivity analysis shows that the penetration rate is the most important parameter,while other parameters have a smaller impact on time series forecasting.It is also found that smoothed data are easier to predict with high accuracy.Nevertheless,over-simplified data can lose real characteristics in time series.In conclusion,the RNN variant can accurately predict the next-step penetration rate,and data smoothing is crucial in time series forecasting.This study provides practical guidance for TBM performance forecasting in practical engineering. 展开更多
关键词 Tunnel boring machine(TBM) Penetration rate(PR) Time series forecasting recurrent neural network(RNN)
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A gated recurrent unit model to predict Poisson’s ratio using deep learning
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作者 Fahd Saeed Alakbari Mysara Eissa Mohyaldinn +4 位作者 Mohammed Abdalla Ayoub Ibnelwaleed A.Hussein Ali Samer Muhsan Syahrir Ridha Abdullah Abduljabbar Salih 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期123-135,共13页
Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to spe... Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error an-alyses.The GRU model showed the proper trends,and the model data ranges were wider than previous ones.The GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs. 展开更多
关键词 Static Poisson’s ratio Deep learning Gated recurrent unit(GRU) Sand control Trend analysis Geomechanical properties
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Aerial target threat assessment based on gated recurrent unit and self-attention mechanism
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作者 CHEN Chen QUAN Wei SHAO Zhuang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期361-373,共13页
Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties ... Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced features.Subsequently, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning. 展开更多
关键词 target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)
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