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Influence of material characteristics on the failure mode and process of landslide dam
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作者 HU Liang ZHONG Qiming +3 位作者 CHEN Liang YANG Meng ZHANG Lucheng WU Hao 《Journal of Mountain Science》 2025年第1期89-109,共21页
Landslide dams,as frequent natural hazards,pose significant risks to human lives,property,and ecological environments.The grading characteristics and density of dam materials play a crucial role in determining the sta... Landslide dams,as frequent natural hazards,pose significant risks to human lives,property,and ecological environments.The grading characteristics and density of dam materials play a crucial role in determining the stability of landslide dams and the potential for dam breaches.To explore the failure mechanisms and evolutionary processes of landslide dams with varying soil properties,this study conducted a series of flume experiments,considering different grain compositions and material densities.The results demonstrated that grading characteristics significantly influence landslide dam stability,affecting failure patterns,breach processes,and final breach morphologies.Fine-graded materials exhibited a sequence of surface erosion,head-cut erosion,and subsequent surface erosion during the breach process,while well-graded materials typically experienced head-cut erosion followed by surface erosion.In coarse-graded dams,the high permeability of coarse particles allowed the dam to remain stable,as inflows matched outflows.The dam breach model experiments also showed that increasing material density effectively delayed the breach and reduced peak breach flow discharge.Furthermore,higher fine particle content led to a reduction in the residual dam height and the base slope of the final breach profile,although the relationship between peak breach discharge and the content of fine and coarse particles was nonlinear.To better understand breach morphology evolution under different soil characteristics and hydraulic conditions,three key points were identified—erosion point,control point,and scouring point.This study,by examining the evolution of failure patterns,breach processes,and breach flow discharges under various grading and density conditions,offers valuable insights into the mechanisms behind landslide dam failures. 展开更多
关键词 Landslide dams OVERTOPPING Grain size distribution Breaching process Outflow discharge
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Numerical investigation of hydro-morphodynamic characteristics of a cascading failure of landslide dams
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作者 ZHONG Qiming CHEN Lingchun +3 位作者 MEI Shengyao SHAN Yibo WU Hao ZHAO Kunpeng 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1868-1885,共18页
A cascading failure of landslide dams caused by strong earthquakes or torrential rains in mountainous river valleys can pose great threats to people’s lives,properties,and infrastructures.In this study,based on the t... A cascading failure of landslide dams caused by strong earthquakes or torrential rains in mountainous river valleys can pose great threats to people’s lives,properties,and infrastructures.In this study,based on the three-dimensional Reynoldsaveraged Navier-Stokes equations(RANS),the renormalization group(RNG)k-εturbulence model,suspended and bed load transport equations,and the instability discriminant formula of dam breach side slope,and the explicit finite volume method(FVM),a detailed numerical simulation model for calculating the hydro-morphodynamic characteristics of cascading dam breach process has been developed.The developed numerical model can simulate the breach hydrograph and the dam breach morphology evolution during the cascading failure process of landslide dams.A model test of the breaches of two cascading landslide dams has been used as the validation case.The comparison of the calculated and measured results indicates that the breach hydrograph and the breach morphology evolution process of the upstream and downstream dams are generally consistent with each other,and the relative errors of the key breaching parameters,i.e.,the peak breach flow and the time to peak of each dam,are less than±5%.Further,the comparison of the breach hydrographs of the upstream and downstream dams shows that there is an amplification effect of the breach flood on the cascading landslide dam failures.Three key parameters,i.e.,the distance between the upstream and the downstream dams,the river channel slope,and the downstream dam height,have been used to study the flood amplification effect.The parameter sensitivity analyses show that the peak breach flow at the downstream dam decreases with increasing distance between the upstream and the downstream dams,and the downstream dam height.Further,the peak breach flow at the downstream dam first increases and then decreases with steepening of the river channel slope.When the flood caused by the upstream dam failure flows to the downstream dam,it can produce a surge wave that overtops and erodes the dam crest,resulting in a lowering of the dam crest elevation.This has an impact on the failure occurrence time and the peak breach flow of the downstream dam.The influence of the surge wave on the downstream dam failure process is related to the volume of water that overtops the dam crest and the erosion characteristics of dam material.Moreover,the cascading failure case of the Xiaogangjian and Lower Xiaogangjian landslide dams has also been used as the representative case for validating the model.In comparisons of the calculated and measured breach hydrographs and final breach morphologies,the relative errors of the key dam breaching parameters are all within±10%,which verify the rationality of the model is applicable to real-world cases.Overall,the numerical model developed in this study can provide important technical support for the risk assessment and emergency treatment of failures of cascading landslide dams. 展开更多
关键词 Cascading landslide dams Cascading dam failure process Detailed numerical simulation model Flood amplification effect Parameter sensitivity analyses
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Pegaspargase induced multiple organ failure with acute lymphoblastic leukemia:A case report
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作者 Su-Xia Bao Xiao-Ling Yuan +1 位作者 Lei Yan Jie Xu 《World Journal of Clinical Cases》 2025年第13期14-19,共6页
BACKGROUND The introduction of pegaspargase has greatly advanced the treatment of acute lymphoblastic leukemia(ALL).In the literature,only one case of pegaspargaseinduced multiple organ failure has been reported,and t... BACKGROUND The introduction of pegaspargase has greatly advanced the treatment of acute lymphoblastic leukemia(ALL).In the literature,only one case of pegaspargaseinduced multiple organ failure has been reported,and the patient died due to multiple organ failure.CASE SUMMARY Herein,we present a rare case of a 40-year-old man with ALL who developed multiple organ failure after treatment with pegaspargase.The patient had two rare phenomena reflecting poor prognosis,including the discrepancy between clinical manifestations and liver function and persistently low alpha-fetoprotein(AFP)levels from subacute liver failure.However,the patient was successfully treated using a multidisciplinary team approach.CONCLUSION This is the first case report of successful treatment of pegaspargase-induced multiple organ failure.The findings emphasize the importance of a multidisciplinary team approach in treating pegaspargase-induced multiple organ failure. 展开更多
关键词 PEGASPARGASE Multiple organ failure Acute lymphoblastic leukemia Liver failure Case report
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Numerical three-dimensional modeling of earthen dam piping failure
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作者 Zhengang Wang 《Water Science and Engineering》 EI CAS CSCD 2024年第1期72-82,共11页
A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil dams.This model is an erosion model,coupled with force/moment equilibrium analyses.Orifice fl... A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil dams.This model is an erosion model,coupled with force/moment equilibrium analyses.Orifice flow and two-dimensional(2D)shallow water equations(SWE)are solved to simulate dam break flows at different breaching stages.Erosion rates of different soils with different construction compaction efforts are calculated using corresponding erosion formulae.The dam's real shape,soil properties,and surrounding area are programmed.Large outer 2D-SWE grids are used to control upstream and downstream hydraulic conditions and control the boundary conditions of orifice flow,and inner 2D-SWE flow is used to scour soil and perform force/moment equilibrium analyses.This model is validated using the European Commission IMPACT(Investigation of Extreme Flood Processes and Uncertainty)Test#5 in Norway,Teton Dam failure in Idaho,USA,and Quail Creek Dike failure in Utah,USA.All calculated peak outflows are within 10%errors of observed values.Simulation results show that,for a V-shaped dam like Teton Dam,a piping breach location at the abutment tends to result in a smaller peak breach outflow than the piping breach location at the dam's center;and if Teton Dam had broken from its center for internal erosion,a peak outflow of 117851 m'/s,which is 81%larger than the peak outflow of 65120 m3/s released from its right abutment,would have been released from Teton Dam.A lower piping inlet elevation tends to cause a faster/earlier piping breach than a higher piping inlet elevation. 展开更多
关键词 3D dam breach model 2D shallow water equations 3D slope stability analysis Piping failure Teton dam Quail Creek Dike
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Effect of insomnia on anxiety and depression:Mediation of cognitive failures and moderated mediation of neuroticism
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作者 Yue Li Jia-Long Yu +3 位作者 Shu-Yi Wang Lu-Xin Xie Jia-Long Hong Sha Liu 《World Journal of Psychiatry》 2025年第2期161-172,共12页
BACKGROUND The coronavirus disease 2019 pandemic has had an ongoing impact on the public’s mental health that requires long-term attention.Exploring the relationship between mental health indicators would aid in iden... BACKGROUND The coronavirus disease 2019 pandemic has had an ongoing impact on the public’s mental health that requires long-term attention.Exploring the relationship between mental health indicators would aid in identifying solutions to improve public mental health.AIM To investigate the prevalence of anxiety,depression,and insomnia and explore the relationship among neuroticism,cognitive failures,and mental health.METHODS A cross-sectional survey was conducted in December 2023 using an online platform to recruit adult participants.The neuroticism,subjective cognitive function,and mental health of the participants were assessed using the neuroticism subscale of the Chinese Big Five Personality Inventory Brief Version,cognitive failures questionnaire,generalized anxiety disorder-7,patient health questionnaire-9,and insomnia severity index.Pearson's correlation analysis,independent samples t-tests,one-way analysis of variance,and structural equation model were used to examine the relationship between mental health indicators.RESULTS A total of 1011 valid questionnaires were collected,of which 343 were completed by male(33.93%)respondents and 668 were completed by female(66.07%)respondents.The rates of anxiety,depression,and insomnia were 41.3%,44.6%,and 36.3%,respectively,most cases of which were mild.Among the mental health indicators,there were significant differences by age and between those with siblings and those who were only children.Neuroticism and cognitive failures were significantly positively correlated with mental health indicators.Further moderated mediation analysis showed that cognitive failures mediated the relationship between insomnia and anxiety and between insomnia and depression,with neuroticism moderating the first half of this pathway and the effect being greater in the low-neuroticism group.CONCLUSION Cognitive failures and neuroticism play important roles in mental health.Therefore,enhancing subjective cognitive function and regulating emotional stability may contribute to the improvement of mental health. 展开更多
关键词 INSOMNIA ANXIETY DEPRESSION NEUROTICISM Cognitive failures
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Prognostic value of combined detection of alpha-fetoprotein,plasma prothrombin activity,and serum prealbumin in acute-on-chronic liver failure
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作者 Rui-Xian Duan Ling Liu +1 位作者 Yan Wang Wen-Ming Wu 《World Journal of Gastrointestinal Surgery》 2025年第2期97-104,共8页
BACKGROUND Acute-on-chronic liver failure(ACLF)is a liver disease based on chronic liver disease,which is significantly influenced by clinical treatment regimen and disease status,and despite the existence of multiple... BACKGROUND Acute-on-chronic liver failure(ACLF)is a liver disease based on chronic liver disease,which is significantly influenced by clinical treatment regimen and disease status,and despite the existence of multiple prognostic assessment indicators for ACLF,the overall sensitivity and accuracy are relatively low.AIM To investigate the prognostic value of the combined detection of alpha-fetoprotein(AFP),plasma prothrombin activity(PTA),and serum prealbumin(PA)in ACLF.METHODS This retrospective study included 87 patients with ACLF admitted from February 2021 to February 2023 and categorized them into the survival(n=47)and death(n=40)groups according to their clinical outcomes 3 months posttreatment.All the participants underwent AFP,PTA,and PA level measurements upon admission.Baseline data,as well as AFP,PTA,and PA levels,were comparatively analyzed.Pearson correlation coefficients were utilized to analyze the correlations of AFP,PTA,and PA with different survival outcomes in patients with ACLF.Receiver operating characteristic(ROC)curves and areas under the curves were used to evaluate the predictive value of AFP,PTA,and PA for ACLF prognosis.RESULTS AFP,PTA,and PA levels were markedly decreased in the death group than in the survival group(P<0.05).Pearson analysis indicated a positive association of the AFP,PTA,and PA levels with the survival of patients with ACLF(P<0.05).ROC curve analysis determined the sensitivity and specificity of the combined diagnosis at 91.24%and 100.00%,respectively,both of which were notably increased compared to the single-index diagnosis.The ROC of their combined diagnosis was 0.989,significantly surpassing 0.907,0.849,and 0.853 of AFP,PTA,and PA,respectively.No statistically significant variance was determined in the sensitivity and specificity of the combined diagnosis vs the single detection(P>0.05).CONCLUSION The combined detection of AFP,PTA,and PA levels demonstrates favorable diagnostic value for the short-term prognosis of patients with ACLF,featuring high sensitivity and specificity. 展开更多
关键词 ALPHA-FETOPROTEIN Prothrombin activity PREALBUMIN Acute-on-chronic liver failure Prognostic value
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Predicting post-hepatectomy liver failure using a nomogram based on portal vein width,inflammatory indices,and the albumin-bilirubin score
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作者 Ke Sun Jiang-Bin Li +3 位作者 Ya-Feng Chen Zhong-Jie Zhai Lang Chen Rui Dong 《World Journal of Gastrointestinal Surgery》 2025年第2期87-96,共10页
BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identif... BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identify potential high-risk PHLF patients as early as possible through preoperative evaluation.AIM To identify risk factors for PHLF and develop a prediction model.METHODS This study included 248 patients with HCC at The Second Affiliated Hospital of Air Force Medical University between January 2014 and December 2023;these patients were divided into a training group(n=164)and a validation group(n=84)via random sampling.The independent variables for the occurrence of PHLF were identified by univariate and multivariate analyses and visualized as nomograms.Ultimately,comparisons were made with traditional models via receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS In this study,portal vein width[odds ratio(OR)=1.603,95%CI:1.288-1.994,P≤0.001],the preoperative neutrophil-to-lymphocyte ratio(NLR)(OR=1.495,95%CI:1.126-1.984,P=0.005),and the albumin-bilirubin(ALBI)score(OR=8.868,95%CI:2.144-36.678,P=0.003)were independent risk factors for PHLF.A nomogram prediction model was developed using these factors.ROC and DCA analyses revealed that the predictive efficacy and clinical value of this model were better than those of traditional models.CONCLUSION A new Nomogram model for predicting PHLF in HCC patients was successfully established based on portal vein width,the NLR,and the ALBI score,which outperforms the traditional model. 展开更多
关键词 NOMOGRAM Hepatocellular carcinoma Post-hepatectomy liver failure Albumin-bilirubin score Portal vein width
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Using fracture mechanics method to analyze the failure mechanism and equilibrium equation of interfacial loess-mudstone landslides
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作者 LI Shuanhu LI Chi GAO Yu 《Journal of Mountain Science》 2025年第1期156-166,共11页
Loess-mudstone landslides are common in the Loess Plateau.Investigations into the mechanical theory of loess-mudstone landslides have become a challenging undertaking due to the distinctive interfacial properties of l... Loess-mudstone landslides are common in the Loess Plateau.Investigations into the mechanical theory of loess-mudstone landslides have become a challenging undertaking due to the distinctive interfacial properties of loess-mudstone and the unique water sensitivity characteristics of mudstone.Hence,it is imperative to develop innovative mechanical models and mathematical equations specifically tailored to loess-mudstone landslides.In this study,we analyze the fracture mechanism of the loess-mudstone sliding zone using plastic fracture mechanics and develop a unique fracture yield model.To calculate the energy release rate during the expansion of the loess-mudstone interface tip region,the shear fracture energy G is applied,which reflects both the yield failure criterion and the fracture failure criterion.To better understand the instability mechanism of loess-mudstone landslides,equilibrium equations based on G are established for tractive,compressive,and tensile loess-mudstone landslides.Based on the equilibrium equation,the critical length Lc of the sliding zone can be used for the safety evaluation of loess-mudstone landslides.In this way,this study proposes a new method for determining the failure mechanism and equilibrium equation of loessmudstone landslides,which resolves their starting mechanism,mechanical equilibrium equations,and safety evaluation indicators,thus justifying the scientific significance and practical value of this research. 展开更多
关键词 Loess-mudstone landslide failure mechanism Shear fracture energy Equilibrium equation Safety factor
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Application of ultrasound elastography and splenic size in predicting post-hepatectomy liver failure:Unveiling new clinical perspectives
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作者 Shan Xu Tao Zhang +3 位作者 Bin-Bo He Jie Liu Tao Kong Qing-Yu Zeng 《World Journal of Gastroenterology》 2025年第4期151-155,共5页
In this article,we discuss the study by Cheng et al,published in the World Journal of Gastroenterology,focusing on predictive methods for post-hepatectomy liver failure(PHLF).PHLF is a common and serious complication,... In this article,we discuss the study by Cheng et al,published in the World Journal of Gastroenterology,focusing on predictive methods for post-hepatectomy liver failure(PHLF).PHLF is a common and serious complication,and accurate prediction is critical for clinical management.The study examines the potential of ultrasound elastography and splenic size in predicting PHLF.Ultrasound elastography reflects liver functional reserve,while splenic size provides additional predictive value.By integrating these factors with serological markers,we developed a comprehensive prediction model that effectively stratifies patient risk and supports personalized clinical decisions.This approach offers new insights into predicting PHLF.These methods not only assist clinicians in identifying high-risk patients earlier but also provide scientific support for personalized treatment strategies.Future research will aim to validate the model's accuracy with larger sample sizes,further enhancing the clinical application of these non-invasive indicators. 展开更多
关键词 Ultrasound elastography Splenic size Post-hepatectomy liver failure Prediction model Risk stratification
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Prediction of posthepatectomy liver failure in patients withhepatocellular carcinoma through ultrasound elastography
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作者 Yan-Qing Ma Xi-Ren Xu +2 位作者 Jie Li Yi Lin Zheng Guan 《World Journal of Gastroenterology》 2025年第4期160-163,共4页
In this article,we comment on the article by Cheng et al published in recently.Posthepatectomy liver failure(PHLF)remains a leading cause of hepatectomyrelated mortality and can be evaluated according to liver reserve... In this article,we comment on the article by Cheng et al published in recently.Posthepatectomy liver failure(PHLF)remains a leading cause of hepatectomyrelated mortality and can be evaluated according to liver reserve function.Liver stiffness(LS)measured by ultrasonic elastography and spleen area demonstrate a strong correlation with hepatic proliferation,fibrosis,and portal vein congestion,thus indirectly reflecting liver reserve function.This article highlights a meticulous study aimed at investigating the potential of two-dimensional shear wave elastography in assessing LS,as well as its integration with spleen area,surgical factors,and laboratory indicators,for predicting the risk of PHLF in hepatocellular carcinoma patients.In this article,we discussed the non-invasive elastography modality by ultrasound and magnetic resonance imaging to assess LS.Based on literature data,we subsequently suggested that several risk factors may contribute to PHLF,including excessive intrahepatic neutrophil accumulation,the formation of neutrophil extracellular traps,end-stage liver disease scores,and albumin-bilirubin scores.Therefore,a more comprehensive study incor-porating detailed information requires further investigation. 展开更多
关键词 Posthepatectomy liver failure Liver stiffness Hepatocellular carcinoma ELASTOGRAPHY ULTRASOUND Magnetic resonance imaging
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Genetic factors that predict response and failure of biologic therapy in inflammatory bowel disease
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作者 Milena Peruhova Daniela Stoyanova +3 位作者 Dimitrina Georgieva Miteva Meglena Kitanova Milko Bozhidarov Mirchev Tsvetelina Velikova 《World Journal of Experimental Medicine》 2025年第1期11-23,共13页
Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical ... Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical assessments,endoscopic evaluations,imaging studies,and biomarker testing,where early diagnosis is essential for effective management and prevention of long-term complications,highlighting the need for continual advancements in diagnostic methods.The intricate interplay between genetic factors and the outcomes of biological therapy is of critical importance.Unraveling the genetic determinants that influence responses and failures to biological therapy holds significant promise for optimizing treatment strategies for patients with IBD on biologics.Through an indepth examination of current literature,this review article synthesizes critical genetic markers associated with therapeutic efficacy and resistance in IBD.Understanding these genetic actors paves the way for personalized approaches,informing clinicians on predicting,tailoring,and enhancing the effectiveness of biological therapies for improved outcomes in patients with IBD. 展开更多
关键词 Inflammatory bowel disease Genetic predictors Inflammatory bowel disease treatment Biologic therapy Biologic therapy response Genetic markers in inflammatory bowel disease Inflammatory bowel disease treatment failure PHARMACOGENOMICS Biologic therapy efficacy Genetic variability
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ON THE HYDRAULIC FAILURE PROBABILITY OF FLOOD CONTROL DAMS
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作者 冯平 贾湖 《Transactions of Tianjin University》 EI CAS 1997年第1期24-29,共6页
In flood control dams it is not only the failure to prevent flood larger than their design carrying capacity, but also the uncertainties of hydraulic factors that cause disasters. In general, the hydraulic risk is not... In flood control dams it is not only the failure to prevent flood larger than their design carrying capacity, but also the uncertainties of hydraulic factors that cause disasters. In general, the hydraulic risk is not considered in most of the hydrological analysis in floodproofing plan and design. In this paper, a method of evaluating the hydraulic risk is developed by employing risk theory, and the concept can easily be extended to other types of risk analysis. As a result, it is possible not to consider the hydraulic resks when the design hydrologic risk of flood control dam is lger. Otherwise, the hydraulic risks must be noticed. The research is very helpful for the development of the flood control theory used at present. 展开更多
关键词 flood control dam loading resistance hydraulic risk
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DAMAGES AND FAILURES OF SMART STRUCTURES
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作者 王鑫伟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期1-5,共5页
According to some observed dama ge phenomena in the smart structure systems, the issues related to the damage and failures of smart structures are addressed in this paper. A few possible damage patterns and the def... According to some observed dama ge phenomena in the smart structure systems, the issues related to the damage and failures of smart structures are addressed in this paper. A few possible damage patterns and the definition of the failure of the smart structures are given. It is pointed out that more attentions should be paid to the functional failures o f smart structures. The effects on the control the static deformation due to par tial debonding of PZT actuators are analyzed by the finite element method. Preli minary numerical results show that partial debonding of PZT actuators may have a p preciate reduction on their actuating ability thus reducing the control ability and accuracy of the smart structures. 展开更多
关键词 smart structures damag es failureS FUNCTION
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Numerical modeling of earthen dam breach due to piping failure 被引量:8
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作者 Sheng-shui Chen Qi-ming Zhong Guang-ze Shen 《Water Science and Engineering》 EI CAS CSCD 2019年第3期169-178,共10页
Based on model tests of earthen dam breach due to piping failure, a numerical model was developed.A key difference from previous research is the assumption that the cross-section of the pipe channel is an arch, with a... Based on model tests of earthen dam breach due to piping failure, a numerical model was developed.A key difference from previous research is the assumption that the cross-section of the pipe channel is an arch, with a rectangle at the bottom and a semicircle at the top before the collapse of the pipe roof, rather than a rectangular or circular cross-section.A shear stress-based erosion rate formula was utilized, and the arched pipe tunnel was assumed to enlarge along its length and width until the overlying soil could no longer maintain stability.Orifice flow and open channel flow were adopted to calculate the breach flow discharge for pressure and free surface flows, respectively.The collapse of the pipe roof was determined by comparing the weight of the overlying soil and the cohesion of the soil on the two sidewalls of the pipe.After the collapse, overtopping failure dominated, and the limit equilibrium method was adopted to estimate the stability of the breach slope when the water flow overtopped.In addition, incomplete and base erosion, as well as one-and two-sided breaches were taken into account.The USDAARS-HERU model test P1, with detailed measured data, was used as a case study, and two artificially filled earthen dam failure cases were studied to verify the model.Feedback analysis demonstrates that the proposed model can provide satisfactory results for modeling the breach flow discharge and breach development process.Sensitivity analysis shows that the soil erodibility and initial piping position significantly affect the prediction of the breach flow discharge.Furthermore, a comparison with a well-known numerical model shows that the proposed model performs better than the NWS BREACH model. 展开更多
关键词 Earthen dam PIPING failure OVERTOPPING failure Breach FLOW NUMERICAL modeling Sensitivity analysis
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Mechanism of principal stress rotation and deformation failure behavior induced by excavation in roadways 被引量:1
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作者 Jianping Zuo Zongyu Ma +2 位作者 Chengyi Xu Shuaifei Zhan Haiyan Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4605-4624,共20页
The failure modes of rock after roadway excavation are diverse and complex.A comprehensive investigation of the internal stress field and the rotation behavior of the stress axis in roadways is essential for elucidati... The failure modes of rock after roadway excavation are diverse and complex.A comprehensive investigation of the internal stress field and the rotation behavior of the stress axis in roadways is essential for elucidating the mechanism of roadway failure.This study aimed to examine the spatial relationship between roadways and stress fields.The law of stress axis rotation under three-dimensional(3D)stress has been extensively studied.A stress model of roadways in the spatial stress field was established,and the far-field stress state at different spatial positions of the roadways was analyzed.A mechanical model of roadways under a 3D stress state was established using far-field stress solutions as boundary conditions.The distribution of principal stressesσ1,σ2 andσ3 around the roadways and the variation of the stress principal axis were solved.It was found that the stability boundary of the stress principal axis exhibits hysteresis when compared with that of the principal stress magnitudes.A numerical analysis model for spatial roadways was established to validate the distribution of principal stress and the mechanism of principal axis rotation.Research has demonstrated that the stress axis undergoes varying degrees of spatial rotation in different orientations and radial depths.Based on the distribution of principal stress and the rotation law of the stress principal axis,the entire evolution mechanism of the two stress adjustments to form the final failure form after roadway excavation has been revealed.The on-site detection results also corroborate the findings presented in this paper.The results provide a basis for the analysis of the failure mechanism under a 3D stress state. 展开更多
关键词 Roadway stress field Principal stress rotation Roadway failure mechanism failure characteristics
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Nomogram based on liver stiffness and spleen area with ultrasound for posthepatectomy liver failure:A multicenter study 被引量:2
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作者 Guang-Wen Cheng Yan Fang +6 位作者 Li-Yun Xue Xiao-Hui Qiao Xue-Qi Li Yan Zhang Jia Guo Xiao-Yan Xie Hong Ding 《World Journal of Gastroenterology》 SCIE CAS 2024年第27期3314-3325,共12页
BACKGROUND Liver stiffness(LS)measurement with two-dimensional shear wave elastography(2D-SWE)correlates with the degree of liver fibrosis and thus indirectly reflects liver function reserve.The size of the spleen inc... BACKGROUND Liver stiffness(LS)measurement with two-dimensional shear wave elastography(2D-SWE)correlates with the degree of liver fibrosis and thus indirectly reflects liver function reserve.The size of the spleen increases due to tissue proliferation,fibrosis,and portal vein congestion,which can indirectly reflect the situation of liver fibrosis/cirrhosis.It was reported that the size of the spleen was related to posthepatectomy liver failure(PHLF).So far,there has been no study combining 2D-SWE measurements of LS with spleen size to predict PHLF.This prospective study aimed to investigate the utility of 2D-SWE assessing LS and spleen area(SPA)for the prediction of PHLF in hepatocellular carcinoma(HCC)patients and to develop a risk prediction model.AIM To investigate the utility of 2D-SWE assessing LS and SPA for the prediction of PHLF in HCC patients and to develop a risk prediction model.METHODS This was a multicenter observational study prospectively analyzing patients who underwent hepatectomy from October 2020 to March 2022.Within 1 wk before partial hepatectomy,ultrasound examination was performed to measure LS and SPA,and blood was drawn to evaluate the patient’s liver function and other conditions.Least absolute shrinkage and selection operator logistic regression and multivariate logistic regression analysis was applied to identify independent predictors of PHLF and develop a nomogram.Nomogram performance was validated further.The diagnostic performance of the nomogram was evaluated with receiver operating charac-teristic curve compared with the conventional models,including the model for end-stage liver disease(MELD)score and the albumin-bilirubin(ALBI)score.RESULTS A total of 562 HCC patients undergoing hepatectomy(500 in the training cohort and 62 in the validation cohort)were enrolled in this study.The independent predictors of PHLF were LS,SPA,range of resection,blood loss,international normalized ratio,and total bilirubin.Better diagnostic performance of the nomogram was obtained in the training[area under receiver operating characteristic curve(AUC):0.833;95%confidence interval(95%CI):0.792-0.873;sensitivity:83.1%;specificity:73.5%]and validation(AUC:0.802;95%CI:0.684-0.920;sensitivity:95.5%;specificity:52.5%)cohorts compared with the MELD score and the ALBI score.CONCLUSION This PHLF nomogram,mainly based on LS by 2D-SWE and SPA,was useful in predicting PHLF in HCC patients and presented better than MELD score and ALBI score. 展开更多
关键词 Shear-wave elastography SPLEEN HEPATECTOMY Posthepatectomy liver failure Hepatocellular carcinoma
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Disturbance failure mechanism of highly stressed rock in deep excavation:Current status and prospects 被引量:3
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作者 Tao Wang Weiwei Ye +3 位作者 Liyuan Liu Kai Liu Naisheng Jiang Xianhui Feng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期611-627,共17页
This article reviews the current status on the dynamic behavior of highly stressed rocks under disturbances.Firstly,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stre... This article reviews the current status on the dynamic behavior of highly stressed rocks under disturbances.Firstly,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stress rock are reviewed,followed by the introduction of scholars’research on deep rock deformation and failure from an energy perspective.Subsequently,with a backdrop of highstress phenomena in deep hard rock,such as rock bursts and core disking,we delve into the current state of research on rock microstructure analysis and residual stresses from the perspective of studying the energy storage mechanisms in rocks.Thereafter,the current state of research on the mechanical response and the energy dissipation of highly stressed rock formations is briefly retrospected.Finally,the insufficient aspects in the current research on the disturbance and failure mechanisms in deep,highly stressed rock formations are summarized,and prospects for future research are provided.This work provides new avenues for the research on the mechanical response and damage-fracture mechanisms of rocks under high-stress conditions. 展开更多
关键词 deep rock with high stress highly stressed rock rock failure residual stress energy release
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AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway 被引量:2
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作者 Qing-Qi Zhang Qian Chen +4 位作者 Pan Cao Chun-Xia Shi Lu-Yi Zhang Lu-Wen Wang Zuo-Jiong Gong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第1期43-51,共9页
Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which ... Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure.Methods:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+AGK2.Cultured L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA groups.The liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also measured.Mitochondriaassociated endoplasmic reticulum membranes(MAMs)were measured by immunofluorescence.Results:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 pre-treatment.In comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 pre-treatment.The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 pretreatment.Compared with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group.AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell.Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells.Conclusions:The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF. 展开更多
关键词 SIRT2 inhibitor AGK2 Acute liver failure MFN2 Ferroptosis
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Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis 被引量:5
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作者 Farah Yasmin Abdul Moeed +7 位作者 Rohan Kumar Ochani Hamna Raheel Malik Ali Ehtsham Awan Ayesha Liaquat Arisha Saleem Muhammad Aamir Nael Hawwa Salim Surani 《World Journal of Cardiology》 2024年第1期40-48,共9页
BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore... BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT. 展开更多
关键词 Left bundle branch pacing Biventricular pacing QRS duration Left ventricular ejection fraction Heart failure
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Time series prediction of reservoir bank landslide failure probability considering the spatial variability of soil properties 被引量:2
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作者 Luqi Wang Lin Wang +3 位作者 Wengang Zhang Xuanyu Meng Songlin Liu Chun Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3951-3960,共10页
Historically,landslides have been the primary type of geological disaster worldwide.Generally,the stability of reservoir banks is primarily affected by rainfall and reservoir water level fluctuations.Moreover,the stab... Historically,landslides have been the primary type of geological disaster worldwide.Generally,the stability of reservoir banks is primarily affected by rainfall and reservoir water level fluctuations.Moreover,the stability of reservoir banks changes with the long-term dynamics of external disastercausing factors.Thus,assessing the time-varying reliability of reservoir landslides remains a challenge.In this paper,a machine learning(ML)based approach is proposed to analyze the long-term reliability of reservoir bank landslides in spatially variable soils through time series prediction.This study systematically investigated the prediction performances of three ML algorithms,i.e.multilayer perceptron(MLP),convolutional neural network(CNN),and long short-term memory(LSTM).Additionally,the effects of the data quantity and data ratio on the predictive power of deep learning models are considered.The results show that all three ML models can accurately depict the changes in the time-varying failure probability of reservoir landslides.The CNN model outperforms both the MLP and LSTM models in predicting the failure probability.Furthermore,selecting the right data ratio can improve the prediction accuracy of the failure probability obtained by ML models. 展开更多
关键词 Machine learning(ML) Reservoir bank landslide Spatial variability Time series prediction failure probability
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