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Causes of a Typical Southern Flood and Northern Drought Event in 2015 over Eastern China

Advances in Atmospheric Sciences 2023年第11期40卷 2092-2107,I0014,I0015页

作者： Zhuoyuan li qing YANG dian YUAN Er LU Zhuguo MA Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Xiongan Institute of Innovation Chinese Academy of SciencesXiongan New Area 071800China

The spatial distribution of summer precipitation anomalies over eastern China often shows a dipole pattern,with anti-phased precipitation anomalies between southern China and northern China,known as the“southern flooding and northern drought”(SF-ND)pattern.In 2015,China experienced heavy rainfall in the south and the worst drought since 1979 in the north,which caused huge social and economic losses.Using reanalysis data,the atmospheric circulation anomalies and possible mechanisms related to the summer precipitation anomalies in 2015 were examined.The results showed that both El Niño and certain atmospheric teleconnections,including the Pacific Japan/East Asia Pacific(PJ/EAP),Eurasia pattern(EU),British–Baikal Corridor pattern(BBC),and Silk Road mode(SR),contributed to the dipole pattern of precipitation anomalies.The combination of these factors caused a southwards shift of the western Pacific subtropical high(WPSH)and a weakening of the East Asian summer monsoon.Consequently,it was difficult for the monsoon front and associated rain band to migrate northwards,which meant that less precipitation occurred in northern China while more precipitation occurred in southern China.This resulted in the SF-ND event.Moreover,further analysis revealed that global sea surface temperature anomalies(SSTAs)or sea-ice anomalies were key to stimulating these atmospheric teleconnections.

关键词： drought flood El Niño atmospheric teleconnection sea surface temperature anomaly

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Probabilistic outlier detection for sparse multivariate geotechnical site investigation data using Bayesian learning

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Geoscience Frontiers 2021年第1期12卷 425-439页

作者： Shuo Zheng Yu-Xin Zhu Dian-Qing Li Zi-Jun Cao Qin-Xuan Deng Kok-Kwang Phoon State Key Laboratory of Water Resources and Hydropower Engineering Science Institute of Engineering Risk and Disaster PreventionWuhan University299 Bayi RoadWuhan 430072China Department of Civil and Environmental Engineering National University of SingaporeBlk E1A#07-031 Engineering Drive 2Singapore 117576Singapore

Various uncertainties arising during acquisition process of geoscience data may result in anomalous data instances(i.e.,outliers)that do not conform with the expected pattern of regular data instances.With sparse multivariate data obtained from geotechnical site investigation,it is impossible to identify outliers with certainty due to the distortion of statistics of geotechnical parameters caused by outliers and their associated statistical uncertainty resulted from data sparsity.This paper develops a probabilistic outlier detection method for sparse multivariate data obtained from geotechnical site investigation.The proposed approach quantifies the outlying probability of each data instance based on Mahalanobis distance and determines outliers as those data instances with outlying probabilities greater than 0.5.It tackles the distortion issue of statistics estimated from the dataset with outliers by a re-sampling technique and accounts,rationally,for the statistical uncertainty by Bayesian machine learning.Moreover,the proposed approach also suggests an exclusive method to determine outlying components of each outlier.The proposed approach is illustrated and verified using simulated and real-life dataset.It showed that the proposed approach properly identifies outliers among sparse multivariate data and their corresponding outlying components in a probabilistic manner.It can significantly reduce the masking effect(i.e.,missing some actual outliers due to the distortion of statistics by the outliers and statistical uncertainty).It also found that outliers among sparse multivariate data instances affect significantly the construction of multivariate distribution of geotechnical parameters for uncertainty quantification.This emphasizes the necessity of data cleaning process(e.g.,outlier detection)for uncertainty quantification based on geoscience data.

关键词： Outlier detection Site investigation Sparse multivariate data Mahalanobis distance Resampling by half-means Bayesian machine learning

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Determination of site-specific soil-water characteristic curve from a limited number of test data-A Bayesian perspective

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Geoscience Frontiers 2018年第6期9卷 1665-1677页

作者： lin Wang Zi-Jun Cao Dian-Qing Li Kok-Kwang Phoon Siu-Kui Au State Key Laboratory of Water Resources and Hydropower Engineering Science Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering(Ministry of Education)Wuhan University8 Donghu South RoadWuhan 430072China Department of Civil and Environmental Engineering National University of SingaporeBlk E1A#07-031 Engineering Drive 2Singapore 117576Singapore Institute for Risk and Uncertainty University of LiverpoolHarrison Hughes BuildingBrownlow HillLiverpoolL69 3GHUnited Kingdom

Determining soilewater characteristic curve(SWCC) at a site is an essential step for implementing unsaturated soil mechanics in geotechnical engineering practice, which can be measured directly through various in-situ and/or laboratory tests. Such direct measurements are, however, costly and timeconsuming due to high standards for equipment and procedural control and limits in testing apparatus. As a result, only a limited number of data points(e.g., volumetric water content vs. matric suction)on SWCC at some values of matric suction are obtained in practice. How to use a limited number of data points to estimate the site-specific SWCC and to quantify the uncertainty(or degrees-of-belief) in the estimated SWCC remains a challenging task. This paper proposes a Bayesian approach to determine a site-specific SWCC based on a limited number of test data and prior knowledge(e.g., engineering experience and judgment). The proposed Bayesian approach quantifies the degrees-of-belief on the estimated SWCC according to site-specific test data and prior knowledge, and simultaneously selects a suitable SWCC model from a number of candidates based on the probability logic. To address computational issues involved in Bayesian analyses, Markov Chain Monte Carlo Simulation(MCMCS), specifically Metropolis-Hastings(M-H) algorithm, is used to solve the posterior distribution of SWCC model parameters, and Gaussian copula is applied to evaluating model evidence based on MCMCS samples for selecting the most probable SWCC model from a pool of candidates. This removes one key limitation of the M-H algorithm, making it feasible in Bayesian model selection problems. The proposed approach is illustrated using real data in Unsaturated Soil Database(UNSODA) developed by U.S. Department of Agriculture. It is shown that the proposed approach properly estimates the SWCC based on a limited number of site-specific test data and prior knowledge, and reflects the degrees-of-belief on the estimated SWCC in a rational and quantitative manner.

关键词： Soilewater characteristic curve Bayesian approach Unsaturated soils Degrees-of-belief UNSODA

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Safety and Efficacy of Endovascular Aortic Repair for Abdominal Aortic Aneurysms with a Hostile Neck Anatomy

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Current Medical Science 2023年第6期43卷 1221-1228页

作者： Zun-xiang KE Ge-zheng CHEN Ke HU Shan ZHANG Peng ZHOU dian-xi CHEN Yi-qing li Qin li Chao YANG Department of Emergency Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Department of Vascular Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

Objective This study aimed to investigate the safety and efficacy of endovascular aortic repair(EVAR)for the treatment of an abdominal aortic aneurysm(AAA)with a hostile neck anatomy(HNA).Methods From January 1,2015 to December 31,2019,a total of 259 patients diagnosed with an AAA who underwent EVAR were recruited into this study.Based on the morphological characteristics of the proximal neck anatomy,the patients were divided into the HNA group and the friendly neck anatomy(FNA)group.The patients were followed up for up to 4 years.Results The average follow-up time was 1056.1±535.5 days.Type I endoleak occurred in 4 patients in the HNA group,and 2 patients in the FNA group.Neither death nor intraoperative switch to open repair occurred in either group.The time of the operation was significantly longer in the HNA group(FNA vs.HNA,99.2±51.1 min vs.117.5±63.8 min,P=0.011).There were no significant differences in short-term clinical success rate(P=0.228)or midterm clinical success rate(P=0.889)between the two groups.The overall mortality rate was 10.4%,and Kaplan-Meier survival analysis indicated that the two groups had similar cumulative survival rates at the end of the follow-up period(P=0.889).Conclusion EVAR was feasible and safe in patients with an AAA with a proximal HNA.The early and midterm results were promising;however,further studies are needed to verify the long-term effectiveness of EVAR.

关键词： abdominal aortic aneurysm hostile aneurysm neck endovascular aortic repair endoleak prognosis

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Safety and effectiveness of electromyography-induced rehabilitation treatment after epidural electrical stimulation for spinal cord injury:study protocol for a prospective,randomized,controlled trial

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Neural Regeneration Research 2023年第4期18卷 819-824页

作者： Xiao-Pei Sun Jie-Jian Shi Yong Bao Jie Zhang Hui-Juan Pan dian-You li Yu liang qing Xie Ruijin Hospital Shanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Ruijin Rehabilitation Hospital ShanghaiChina

Epidural electrical stimulation is a new treatment method for spinal cord injury(SCI).Its efficacy and safety have previously been reported.Rehabilitation treatment after epidural electrical stimulation is important to ensure and improve the postoperative efficacy of epidural electrical stimulation in patients with SCI.Considering that electromyography(EMG)-induced rehabilitation treatment can accurately match the muscle contraction of patients with SCI,we designed a study protocol for a prospective,randomized controlled trial.In this trial,on the premise of adjusting the spinal cord electrical stimulator to obtain the maximum EMG signal of the target muscle,patients with SCI receiving epidural electrical stimulation will undergo EMG-induced rehabilitation treatment.Recovery of muscle strength of key muscles,quality of life,safety and therapeutic effects will be monitored.Twenty patients with SCI who are scheduled to undergo epidural electrical stimulation in Shanghai Ruijin Rehabilitation Hospital will be randomly divided into two groups with 10 patients per group.The control group will receive conventional rehabilitation treatment.The EMG-induced rehabilitation group will receive EMG-induced rehabilitation treatment of the target muscles of the upper and lower limbs based on conventional rehabilitation treatment.After rehabilitation treatment,follow up for all patients will occur at 2 weeks and 1,3 and 6 months.The primary outcome measure of this trial will be evaluation of target muscle recovery using the Manual Muscle Testing grading scale.Secondary outcome measures will include modified Barthel Index scores,integrated EMG values,the visual analogue scale,Spinal Cord Independence Measure scores,and modified Ashworth scale scores.The safety indicator will be the incidence of adverse events.This trial will collect data regarding the therapeutic effects of EMG-induced rehabilitation in patients with SCI receiving epidural electrical stimulation for 6 months after rehabilitation treatment.Findings from this trial

关键词： electromyography-induced rehabilitation epidural electrical stimulation muscle strength pain quality of life randomized controlled trial recovery spinal cord injury

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Microstructure,fracture behavior,in vitro corrosion resistance,and cytotoxicity of Zn-Mg/Mg-Zn-HAp laminated composites produced by spark plasma sintering

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Rare Metals 2021年第4期40卷 939-951页

作者： Ya-Kai Zhang Ze-Qin Cui dian-qing Gong Wen-Xian Wang Wei-li Cheng School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of TechnologyTaiyuan 030024China Shanxi Province Boiler and Pressure Vessel Supervision and Inspection Institute Taiyuan 030024China

Ideal biodegradable materials exhibit suitable degradation rates and sufficient mechanical properties for their specific application.With these parameters in mind,Zn-Mg/Mg-Zn-hydroxyapatite(HAp) laminated composites were designed and fabricated by spark plasma sintering.This paper describes the structure,mechanical properties,in vitro corrosion resistance,and cytotoxicity of the Zn-Mg/Mg-Zn-HAp laminated composites.The compressive strength and elastic moduli of the laminated composites matched that of cortical bone and could effectively reduce the stress shielding effect as an implant with good biomechanical compatibility.Analysis of the fracture path and morphology after fracture toughness tests indicated that the Zn-Mg/Mg-Zn-HAp laminated composites exhibited significant capacity to prevent crack propagation,improving the fracture toughness.In vitro degradation experiments showed that the design of the laminated structure can provide a gradient degradation rate for the material.Furthermore,the laminated composites exhibited excellent biocompatibility and are promising candidates for orthopedic implants.

关键词： Laminated composites Zn-Mg composites Spark plasma sintering Microstructure Fracture behavior In vitro degradation Cytotoxicity

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基桩可靠度分析的统计相关性评价方法

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岩土力学 2008年第3期29卷 633-638页

作者：李典庆武汉大学水资源与水电工程科学国家重点实验室武汉430072

为了评估不同失效准则对基桩可靠度的影响,传统的方法是引入失效准则偏差系数。然而目前所定义的失效准则偏差系数使得偏差系数和基本随机变量之间具有一定的相关性,直接将偏差系数的统计参数用于基桩可靠度分析是不尽合理的。为此,基... 详细信息

为了评估不同失效准则对基桩可靠度的影响,传统的方法是引入失效准则偏差系数。然而目前所定义的失效准则偏差系数使得偏差系数和基本随机变量之间具有一定的相关性,直接将偏差系数的统计参数用于基桩可靠度分析是不尽合理的。为此,基于线性回归理论提出了新的失效准则偏差系数的定义,并采用Spearman秩相关系数方法检验了偏差系数和基本随机变量之间的相关性。采用算例分析了偏差系数和基本随机变量之间的相关性对基桩可靠度的影响。结果表明,传统的失效准则偏差系数的定义使得偏差系数和基本随机变量之间具有一定的相关性,提出的通用的失效准则偏差系数能够有效地消除这种相关性。偏差系数与基本随机变量之间的相关性对偏差系数的均值具有明显的影响,但对变异系数基本没有影响。此外,偏差系数与基本随机变量间的相关性对基桩可靠指标具有明显的影响,基桩可靠度分析中应该消除这种相关性。

关键词：基桩失效准则偏差系数 Spearman秩相关系数相关性

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Perivenous application of fibrin glue prevents the early injury of jugular vein graft to arterial circulation in rabbits

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Chinese Medical Journal 2006年第4期119卷 300-304页

作者： WAN li li dian-yuan YANG Bing WU qing-yu Department of Cardiovascular Surgery Cardiovascular Institute Fu Wai Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100037 China Department of Cardiovascular Surgery Cardiovascular Institute First Affiliated Hospital of Tsinghua University Beijing 100006 China

Background Placement of an external support has been reported to prevent intimal hyperplasia of vein grafts. However, it is limited by potential complications. In the present study, we investigated the effect of fibrin glue on preventing vein graft failure as perivenous application. Methods Twenty-four rabbits were divided into non-supported group （n=12） and fibrin glue group （n=12）. All animals underwent unilateral jugular vein into common carotid artery interposition grafting and then fibrin glue was applied as perivenous support. Samples of tissues were harvested after 4 weeks. Results The vein grafts with fibrin glue demonstrated a statistically significant decrease in proliferating cell nuclear antigen in the medial/intimal region [13.38% （11.26%-15.11%）] compared with non-supported vein grafts [31.22% （27.15%-35.98%）] （P〈0.001）. light microscopy showed remarkable attenuation of endothelial cell loss and numerous microvessels in neoadventitia in the fibrin glue group compared with the non-supported group. The smooth muscle cells migrated into adventitia significantly in fibrin glue group, whereas the smooth muscle ceils migrated into intima in non-supported group. Conclusion Perivenous support of vein graft with fibrin glue in vivo can attenuate the severe injury encountered in the non-supported vein grafts exposed to artery.

关键词： perivenous support fibrin glue vein graft

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打入桩承载力确定方法对安全系数的影响

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岩土力学 2006年第10期27卷 1733-1738页

作者：李典庆武汉大学水资源与水电工程科学国家重点实验室武汉430072

在传统的容许应力设计方法中桩基承载力安全系数取决于桩基承载力的确定方法,然而,基于经验选择的承载力安全系数缺少理论依据,为此,基于贝叶斯理论和线性回归方法提出了评价桩基承载力确定方法对承载力安全系数影响的方法,给出了现行... 详细信息

在传统的容许应力设计方法中桩基承载力安全系数取决于桩基承载力的确定方法,然而,基于经验选择的承载力安全系数缺少理论依据,为此,基于贝叶斯理论和线性回归方法提出了评价桩基承载力确定方法对承载力安全系数影响的方法,给出了现行规范对于不同承载力确定方法采用不同安全系数的理论依据,阐明了桩基动力测试降低安全系数的理论依据,并以7种桩基设计方法为例,分析了承载力确定方法对安全系数的影响。结果表明,采用所提出的方法计算的安全系数基本上与现行的经验值相一致,表明精确的承载力确定方法可以有效地降低承载力安全系数,设计方法、承载力确定方法和水平都对安全系数有影响,但当承载力试验桩的数目足够多时,安全系数对于设计方法的精确性不敏感。

关键词：打入桩桩基承载力安全系数贝叶斯分析线性回归

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Neuroprotective effects of salidroside on focal cerebral ischemia/reperfusion injury involve the nuclear erythroid 2-related factor 2 pathway

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Neural Regeneration Research 2015年第12期10卷 1989-1996页

作者： Jing Han qing Xiao Yan-hua lin Zhen-zhu Zheng Zhao-dong He Juan Hu li-dian Chen Institute of Materia Medica Fujian Academy of Traditional Chinese Medicine Fujian University of Traditional Chinese Medicine

Salidroside,the main active ingredient extracted from Rhodiola crenulata,has been shown to be neuroprotective in ischemic cerebral injury,but the underlying mechanism for this neuroprotection is poorly understood.In the current study,the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2（Nrf2）pathway was investigated in a rat model of middle cerebral artery occlusion.Salidroside（30 mg/kg）reduced infarct size,improved neurological function and histological changes,increased activity of superoxide dismutase and glutathione-S-transferase,and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion.Furthermore,salidroside apparently increased Nrf2 and heme oxygenase-1 expression.These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved.The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke.

关键词： nerve regeneration traditional Chinese medicine salidroside cerebral ischemia andreperfusion nuclear factor erythroid 2-related factor 2 heme oxygenase-1 middle cerebral arteryocclusion model superoxide dismutase neuroprotection neural regeneration

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