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Nucleotide excision repair gene polymorphisms and hepatoblastoma susceptibility in Eastern Chinese children:A five-center case-control study
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作者 Huimin Yin Xianqiang Wang +6 位作者 Shouhua Zhang Shaohua He Wenli Zhang Hongting Lu Yizhen Wang Jing He Chunlei Zhou 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第3期298-305,共8页
Objective:Nucleotide excision repair(NER)plays a vital role in maintaining genome stability,and the effect of NER gene polymorphisms on hepatoblastoma susceptibility is still under investigation.This study aimed to ev... Objective:Nucleotide excision repair(NER)plays a vital role in maintaining genome stability,and the effect of NER gene polymorphisms on hepatoblastoma susceptibility is still under investigation.This study aimed to evaluate the relationship between NER gene polymorphisms and the risk of hepatoblastoma in Eastern Chinese Han children.Methods:In this five-center case-control study,we enrolled 966 subjects from East China(193 hepatoblastoma patients and 773 healthy controls).The TaqMan method was used to genotype 19 single nucleotide polymorphisms(SNPs)in NER pathway genes,including ERCC1,XPA,XPC,XPD,XPF,and XPG.Then,multivariate logistic regression analysis was performed,and odds ratios(ORs)and 95%confidence intervals(95%CIs)were utilized to assess the strength of associations.Results:Three SNPs were related to hepatoblastoma risk.XPC rs2229090 and XPD rs3810366 significantly contributed to hepatoblastoma risk according to the dominant model(adjusted OR=1.49,95%CI=1.07−2.08,P=0.019;adjusted OR=1.66,95%CI=1.12−2.45,P=0.012,respectively).However,XPD rs238406 conferred a significantly decreased risk of hepatoblastoma under the dominant model(adjusted OR=0.68,95%CI=0.49−0.95;P=0.024).Stratified analysis demonstrated that these significant associations were more prominent in certain subgroups.Moreover,there was evidence of functional implications of these significant SNPs suggested by online expression quantitative trait loci(eQTLs)and splicing quantitative trait loci(sQTLs)analysis.Conclusions:In summary,NER pathway gene polymorphisms(XPC rs2229090,XPD rs3810366,and XPD rs238406)are significantly associated with hepatoblastoma risk,and further research is required to verify these findings. 展开更多
关键词 Nucleotide excision repair POLYMORPHISMS HEPATOBLASTOMA SUSCEPTIBILITY
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Comparing short-term outcomes of robot-assisted and conventional laparoscopic total mesorectal excision surgery for rectal cancer in elderly patients
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作者 Hao Yang Gang Yang +3 位作者 Wen-Ya Wu Fang Wang Xue-Quan Yao Xiao-Yu Wu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1271-1279,共9页
BACKGROUND Da Vinci Robotics-assisted total mesorectal excision(TME)surgery for rectal cancer is becoming more widely used.There is no strong evidence that roboticassisted surgery and laparoscopic surgery have similar... BACKGROUND Da Vinci Robotics-assisted total mesorectal excision(TME)surgery for rectal cancer is becoming more widely used.There is no strong evidence that roboticassisted surgery and laparoscopic surgery have similar outcomes in elderly patients with TME for rectal cancer.AIM To determine the improved oncological outcomes and short-term efficacy of robot-assisted surgery in elderly patients undergoing TME surgery.METHODS A retrospective study of the clinical pathology and follow-up of elderly patients who underwent TME surgery at the Department of Gastrointestinal Oncology at the Affiliated Hospital of Nanjing University of Chinese Medicine was conducted from March 2020 through September 2023.The patients were divided into a robotassisted group(the R-TME group)and a laparoscopic group(the L-TME group),and the short-term efficacy of the two groups was compared.RESULTS There were 45 elderly patients(≥60 years)in the R-TME group and 50 elderly patients(≥60 years)in the L-TME group.There were no differences in demographics,conversion rates,or postoperative complication rates.The L-TME group had a longer surgical time than the R-TME group[145(125,187.5)vs 180(148.75,206.25)min,P=0.005),and the first postoperative meal time in the L-TME group was longer than that in the R-TME(4 vs 3 d,P=0.048).Among the sex and body mass index(BMI)subgroups,the R-TME group had better out-comes than did the L-TME group in terms of operation time(P=0.042)and intraoperative assessment of bleeding(P=0.042).In the high BMI group,catheter removal occurred earlier in the R-TME group than in the L-TME group(3 vs 4 d,P=0.001),and autonomous voiding function was restored.CONCLUSION The curative effect and short-term efficacy of robot-assisted TME surgery for elderly patients with rectal cancer are similar to those of laparoscopic TME surgery;however,robotic-assisted surgery has better short-term outcomes for individuals with risk factors such as obesity and pelvic stenosis.Optimizing the learning curve can shorten the operation time,reduce the recovery time of gastrointestinal function,and improve the prognosis. 展开更多
关键词 Robotic surgery LAPAROSCOPY Rectal cancer Total mesorectal excision ELDERLY
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Adverse Pregnancy Outcomes Following Cryotherapy, Thermal Ablation and Loop Electrosurgical Excision Procedure for Cervical Intraepithelial Neoplasia Treatment: A Pilot Study among Zambian Women
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作者 Victoria Mwiinga-Kalusopa Johanna E. Maree +1 位作者 Concepta Kwaleyela Patricia Katowa-Mukwato 《Open Journal of Obstetrics and Gynecology》 2024年第1期7-17,共11页
Background: Cervical Intraepithelial neoplasia treatments have become essential interventions to manage cervical lesions. Majority of the recipients of these treatments are women within the reproductive age group, who... Background: Cervical Intraepithelial neoplasia treatments have become essential interventions to manage cervical lesions. Majority of the recipients of these treatments are women within the reproductive age group, who according to literature may be at risk of adverse pregnancy outcomes. This pilot study is part of a study investigating adverse pregnancy outcomes among women who received Cryotherapy, Thermal ablation and Loop Electrosurgical Excision Procedure compared to the untreated women in Zambia. Materials and Methods: This descriptive study analyzed records of 886 (n = 443 treated and n = 443 untreated) women aged 15 - 49 years. The women were either screened with Visual Inspection with Acetic Acid or treated for Cervical Intraepithelial neoplasia at the Adult Infectious Disease Centre between January 2010 and December 2020. Women meeting the criteria were identified using the Visual Inspection with Acetic Acid screening records and telephone interviews to obtain the adverse pregnancy outcome experienced. Data were analysed using STATA version 16 to determine the prevalence and obtain frequency distribution of outcomes of interest. Univariate and multivariable binary logistic regression estimated odds of adverse pregnancy outcomes across the three treatments. Results: The respondents were aged 15 to 49 years. Adverse pregnancy outcomes were observed to be more prevalent in the treatment group (18.5%) compared to the untreated group (5.4%). Normal pregnancy outcomes were lower in the treated (46.3%;n = 443) than the untreated (53.7%;n = 443). The treated group accounted for the majority of abortions (85.2%), prolonged labour (85.7%) and low birth weight (80%), whereas, the untreated accounted for the majority of still births (72.7%). Women treated with cryotherapy (aOR = 2.43, 95% CI = 1.32 - 4.49, p = 0.004), thermal ablation (aOR = 6.37, 95% CI = 0.99 - 41.2, p = 0.052) and Loop Electrosurgical Excision Procedure (aOR = 9.67, 95% CI = 2.17 - 43.1, p = 0.003) had two-, six- and ten-times higher odds of adverse pregnancy outcomes respectively, relative to women who required no treatment. Conclusion: Adverse pregnancy outcomes are prevalent among women who have received treatment in Zambia. The findings indicate that treating Cervical Intraepithelial Neoplasia has been linked to higher chances of experiencing abortion, delivering low birth weight babies and enduring prolonged labor that may result in a caesarean section delivery. Cervical neoplasia treatments, particularly Loop Electrosurgical Excision Procedure, are associated with significantly increased odds of adverse pregnancy outcomes. It is essential to include information about prior Cervical Intraepithelial neoplasia treatment outcomes in obstetric care. 展开更多
关键词 Adverse Pregnancy Outcomes Cervical Intraepithelial Neoplasia Cryothera-py Thermal Ablation Loop Electrosurgical excision Procedure PILOT Repro-ductive Age
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Clinical Study on the Treatment of Low Anal Fistula in Infants and Young Children by Anal Gland Excision and Virtual Hanging Procedure
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作者 Hongbo Su Linmei Sun +5 位作者 Yimiao Liang Jiansheng Hu Yongli Zhang Ni Wei Chaoyang Li Lin Tang 《Journal of Clinical and Nursing Research》 2024年第3期18-25,共8页
Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admit... Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision. 展开更多
关键词 Anal fistula Anal gland excision Virtual hanging procedure Surgical method Observation index Clinical efficacy
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Laparoscopic right radical hemicolectomy: Central vascular ligation and complete mesocolon excision vs D3 lymphadenectomy - How I do it?
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作者 Kaushal Yadav 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1521-1526,共6页
In colon cancer surgery,ensuring the complete removal of the primary tumor and draining lymph nodes is crucial.Lymphatic drainage in the colon follows the vascular supply,typically progressing from pericolic to paraao... In colon cancer surgery,ensuring the complete removal of the primary tumor and draining lymph nodes is crucial.Lymphatic drainage in the colon follows the vascular supply,typically progressing from pericolic to paraaortic lymph nodes.While NCCN guidelines recommend the removal of 10-12 lymph nodes for ade-quate oncological resection,achieving complete oncological resection involves more than just meeting these numerical targets.Various techniques have been developed and studied over time to attain optimal oncological outcomes.A key technique central to this goal is identifying the ileocolic vessels at their origin from the superior mesenteric vessels.Complete excision of the visceral and parietal mesocolon ensures the intact removal of the specimen,while D3 lymphade-nectomy targets all draining regional lymph nodes.Although these principles emphasize different aspects,they ultimately converge to achieve the same goal of complete oncological resection.This article aims to simplify the surgical steps that align with the principle of central vascular ligation and mesocolon mobilization while ensuring adequate D3 dissection. 展开更多
关键词 Carcinoma caecum Carcinoma ascending colon Right hemicolectomy Extended right hemicolectomy Central vascular ligation Complete mesocolon excision D3 lymphadenectomy Laparoscopic right hemicolectomy Minimally invasive hemico-lectomy
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Clinical Outcomes of Complete Mesocolic Excision for Right-Sided Colon Cancer Using 3D Laparoscopy versus 2D Laparoscopy
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作者 Guodong Zhao Zhe Shi +1 位作者 Liang Xue Shugang Sun 《Proceedings of Anticancer Research》 2024年第4期157-162,共6页
Objective:To study the clinical outcomes of complete mesocolic excision(CME)for right-sided colon cancer using 3D(three-dimensional)laparoscopy compared to 2D(two-dimensional)laparoscopy.Methods:From January 2022 to D... Objective:To study the clinical outcomes of complete mesocolic excision(CME)for right-sided colon cancer using 3D(three-dimensional)laparoscopy compared to 2D(two-dimensional)laparoscopy.Methods:From January 2022 to December 2023,58 patients with right-sided colon cancer treated at the Affiliated Hospital of Hebei Engineering University were randomly divided into a 3D laparoscopy group(observation group)and a 2D laparoscopy group(control group),with 29 patients in each group.Intraoperative blood loss,postoperative time to first flatulence,length of hospital stay,and incidence of complications in both groups were recorded.Results:There was a statistically significant difference in intraoperative blood loss between the two groups(P<0.05).There was no statistically significant difference in the time to first flatulence between the groups(P>0.05).However,there was a statistically significant difference in the length of hospital stay(P<0.05)and the incidence of complications(P<0.05)between the two groups.Conclusion:3D laparoscopy for CME can reduce intraoperative blood loss,shorten hospital stay,and decrease postoperative complications,showing significant clinical advantages over traditional 2D laparoscopy. 展开更多
关键词 3D laparoscopy 2D laparoscopy Complete mesocolic excision Colon cancer
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Early burn wound excision in mass casualty events 被引量:1
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作者 Agnieszka Surowiecka Tomasz Korzeniowski Jerzy Struzyna 《Military Medical Research》 SCIE CAS CSCD 2023年第2期279-280,共2页
Dear Editor,The aim of the letter is to stress the need of creating unified recommendations concerning early burn wound excision in cases of mass casualty burns exclusively.There are several triage methods,both for ci... Dear Editor,The aim of the letter is to stress the need of creating unified recommendations concerning early burn wound excision in cases of mass casualty burns exclusively.There are several triage methods,both for civilian and military circumstances,that govern burn casualty triage and evacuation from the incident site,as well as hospital referral up to 120 h from the disaster. 展开更多
关键词 Burn wound Early excision Enzymatic debridement
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:4
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn Extraction method STRUCTURE Rheological properties Antioxidant activity Bile acid binding capacity
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Drilling-based measuring method for the c-φ parameter of rock and its field application 被引量:2
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作者 Bei Jiang Fenglin Ma +5 位作者 Qi Wang Hongke Gao Dahu Zhai Yusong Deng Chuanjie Xu Liangdi Yao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期65-76,共12页
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R... The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters. 展开更多
关键词 Digital drilling Rock crushing zone c-u parameter Measurement method Field application
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Volumetric lattice Boltzmann method for pore-scale mass diffusionadvection process in geopolymer porous structures 被引量:1
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作者 Xiaoyu Zhang Zirui Mao +6 位作者 Floyd W.Hilty Yulan Li Agnes Grandjean Robert Montgomery Hans-Conrad zur Loye Huidan Yu Shenyang Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2126-2136,共11页
Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advecti... Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advection process within porous structures is essential for material design.In this study,we present advancements in the volumetric lattice Boltzmann method(VLBM)for modeling and simulating pore-scale diffusion-advection of radioactive isotopes within geopolymer porous structures.These structures are created using the phase field method(PFM)to precisely control pore architectures.In our VLBM approach,we introduce a concentration field of an isotope seamlessly coupled with the velocity field and solve it by the time evolution of its particle population function.To address the computational intensity inherent in the coupled lattice Boltzmann equations for velocity and concentration fields,we implement graphics processing unit(GPU)parallelization.Validation of the developed model involves examining the flow and diffusion fields in porous structures.Remarkably,good agreement is observed for both the velocity field from VLBM and multiphysics object-oriented simulation environment(MOOSE),and the concentration field from VLBM and the finite difference method(FDM).Furthermore,we investigate the effects of background flow,species diffusivity,and porosity on the diffusion-advection behavior by varying the background flow velocity,diffusion coefficient,and pore volume fraction,respectively.Notably,all three parameters exert an influence on the diffusion-advection process.Increased background flow and diffusivity markedly accelerate the process due to increased advection intensity and enhanced diffusion capability,respectively.Conversely,increasing the porosity has a less significant effect,causing a slight slowdown of the diffusion-advection process due to the expanded pore volume.This comprehensive parametric study provides valuable insights into the kinetics of isotope uptake in porous structures,facilitating the development of porous materials for nuclear waste treatment applications. 展开更多
关键词 Volumetric lattice Boltzmann method(VLBM) Phase field method(PFM) Pore-scale diffusion-advection Nuclear waste treatment Porous media flow Graphics processing unit(GPU) parallelization
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Anaesthetic Management and Challenges for Carotid Body Tumour Excision in a Young Nigerian: A Case Report and Review of Literature
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作者 Florence A. O. Oguntade Moses Ayodele Akinola +2 位作者 Oluwapelumi O. Olusoga-Peters Bukola Adesola Olayinka Rachael Adetola Adeoti 《Case Reports in Clinical Medicine》 2023年第5期139-147,共9页
Background: Carotid body tumours (CBTs) are rare tumours that arise from chemoreceptor cells at the bifurcation of carotid artery. Excision of CBT poses several anesthetic challenges and may be complicated with marked... Background: Carotid body tumours (CBTs) are rare tumours that arise from chemoreceptor cells at the bifurcation of carotid artery. Excision of CBT poses several anesthetic challenges and may be complicated with marked intraoperative hemodynamic instability and turbulent postoperative recovery. Attention to details and a meticulous anesthetic plan are essential for successful anesthetic management. Aim: To present anaesthetic management and challenges for carotid body tumour excision in a young Nigerian. Case Presentation: A 26-year-old man presented with left sided slow growing neck tumour. The tumour was completely excised with no anaesthetic or surgical complication. Histology and immunohistochemistry of the excised tumour confirmed paraganglioma. He was discharged fifteenth post-operative day. Conclusion: General anesthesia is the preferred technique. The basic elements of anesthetic management are protection of hemodynamic stability and maintenance of cerebral perfusion pressure (CPP). 展开更多
关键词 ANAESTHESIA Carotid Body Tumour excision COMPLICATIONS
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Material point method simulation of hydro-mechanical behaviour in twophase porous geomaterials: A state-of-the-art review 被引量:1
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作者 Xiangcou Zheng Shuying Wang +1 位作者 Feng Yang Junsheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2341-2350,共10页
The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current stat... The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous geomaterials.The review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large deformations.The focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers. 展开更多
关键词 Coupled problems Hydro-mechanical behaviour Large deformation Material Point method(MPM)
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Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers 被引量:1
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作者 DU Zun-feng ZHU Hai-ming YU Jian-xing 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期285-296,共12页
When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fa... When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real risers.The problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration modes.However,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known measurements.This study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal space.In the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring. 展开更多
关键词 motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing
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Numerical manifold method for thermo-mechanical coupling simulation of fractured rock mass 被引量:1
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作者 Jiawei Liang Defu Tong +3 位作者 Fei Tan Xiongwei Yi Junpeng Zou Jiahe Lv 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1977-1992,共16页
As a calculation method based on the Galerkin variation,the numerical manifold method(NMM)adopts a double covering system,which can easily deal with discontinuous deformation problems and has a high calculation accura... As a calculation method based on the Galerkin variation,the numerical manifold method(NMM)adopts a double covering system,which can easily deal with discontinuous deformation problems and has a high calculation accuracy.Aiming at the thermo-mechanical(TM)coupling problem of fractured rock masses,this study uses the NMM to simulate the processes of crack initiation and propagation in a rock mass under the influence of temperature field,deduces related system equations,and proposes a penalty function method to deal with boundary conditions.Numerical examples are employed to confirm the effectiveness and high accuracy of this method.By the thermal stress analysis of a thick-walled cylinder(TWC),the simulation of cracking in the TWC under heating and cooling conditions,and the simulation of thermal cracking of the SwedishÄspöPillar Stability Experiment(APSE)rock column,the thermal stress,and TM coupling are obtained.The numerical simulation results are in good agreement with the test data and other numerical results,thus verifying the effectiveness of the NMM in dealing with thermal stress and crack propagation problems of fractured rock masses. 展开更多
关键词 Heat conduction Fractured rock mass Crack propagation Galerkin variation Numerical manifold method(NMM)
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A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics 被引量:1
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作者 Liang Wang Xue Zhang +1 位作者 Jingjing Meng Qinghua Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2172-2183,共12页
In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated soils.Our approach incorporates the nodal integration technique into a gene... In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated soils.Our approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM formulation.To mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing technique.By discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the PFEM.We express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)problem.Stresses,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point method.Consequently,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM formulation.Numerical experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM approaches.This work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics. 展开更多
关键词 Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)
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An inverse analysis of fluid flow through granular media using differentiable lattice Boltzmann method 被引量:1
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作者 Qiuyu Wang Krishna Kumar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2077-2090,共14页
This study presents a method for the inverse analysis of fluid flow problems.The focus is put on accurately determining boundary conditions and characterizing the physical properties of granular media,such as permeabi... This study presents a method for the inverse analysis of fluid flow problems.The focus is put on accurately determining boundary conditions and characterizing the physical properties of granular media,such as permeability,and fluid components,like viscosity.The primary aim is to deduce either constant pressure head or pressure profiles,given the known velocity field at a steady-state flow through a conduit containing obstacles,including walls,spheres,and grains.The lattice Boltzmann method(LBM)combined with automatic differentiation(AD)(AD-LBM)is employed,with the help of the GPU-capable Taichi programming language.A lightweight tape is used to generate gradients for the entire LBM simulation,enabling end-to-end backpropagation.Our AD-LBM approach accurately estimates the boundary conditions for complex flow paths in porous media,leading to observed steady-state velocity fields and deriving macro-scale permeability and fluid viscosity.The method demonstrates significant advantages in terms of prediction accuracy and computational efficiency,making it a powerful tool for solving inverse fluid flow problems in various applications. 展开更多
关键词 Inverse problem Fluid flow Granular media Automatic differentiation(AD) Lattice Boltzmann method(LBM)
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Robustness Study and Superior Method Development and Validation for Analytical Assay Method of Atropine Sulfate in Pharmaceutical Ophthalmic Solution
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作者 Md. Nazmus Sakib Chowdhury Sreekanta Nath Dalal +4 位作者 Md. Ariful Islam Md. Anwar Hossain Pranab Kumar Das Shakawat Hossain Parajit Das 《American Journal of Analytical Chemistry》 CAS 2024年第5期151-164,共14页
Background: The robustness is a measurement of an analytical chemical method and its ability to contain unaffected by little with deliberate variation of analytical chemical method parameters. The analytical chemical ... Background: The robustness is a measurement of an analytical chemical method and its ability to contain unaffected by little with deliberate variation of analytical chemical method parameters. The analytical chemical method variation parameters are based on pH variability of buffer solution of mobile phase, organic ratio composition changes, stationary phase (column) manufacture, brand name and lot number variation;flow rate variation and temperature variation of chromatographic system. The analytical chemical method for assay of Atropine Sulfate conducted for robustness evaluation. The typical variation considered for mobile phase organic ratio change, change of pH, change of temperature, change of flow rate, change of column etc. Purpose: The aim of this study is to develop a cost effective, short run time and robust analytical chemical method for the assay quantification of Atropine in Pharmaceutical Ophthalmic Solution. This will help to make analytical decisions quickly for research and development scientists as well as will help with quality control product release for patient consumption. This analytical method will help to meet the market demand through quick quality control test of Atropine Ophthalmic Solution and it is very easy for maintaining (GDP) good documentation practices within the shortest period of time. Method: HPLC method has been selected for developing superior method to Compendial method. Both the compendial HPLC method and developed HPLC method was run into the same HPLC system to prove the superiority of developed method. Sensitivity, precision, reproducibility, accuracy parameters were considered for superiority of method. Mobile phase ratio change, pH of buffer solution, change of stationary phase temperature, change of flow rate and change of column were taken into consideration for robustness study of the developed method. Results: The limit of quantitation (LOQ) of developed method was much low than the compendial method. The % RSD for the six sample assay of developed method was 0.4% where the % RSD of the compendial method was 1.2%. The reproducibility between two analysts was 100.4% for developed method on the contrary the compendial method was 98.4%. 展开更多
关键词 ROBUSTNESS method Validation HPLC Compendial method method Development GDP LOQ
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Hybrid Strategy of Partitioned and Monolithic Methods for Solving Strongly Coupled Analysis of Inverse and Direct Piezoelectric and Circuit Coupling
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作者 Daisuke Ishihara Syunnosuke Nozaki +1 位作者 Tomoya Niho Naoto Takayama 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1371-1386,共16页
The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct n... The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct numerical modeling for this phenomenon can be classified into partitioned or monolithic formulations.Each formulation has its advantages and disadvantages,and the choice depends on the characteristics of each coupled problem.This study proposes a new option:a coupled analysis strategy that combines the best features of the existing formulations,namely,the hybrid partitioned-monolithic method.The analysis of inverse piezoelectricity and the monolithic analysis of direct piezoelectric and circuit interaction are strongly coupled using a partitioned iterative hierarchical algorithm.In a typical benchmark problem of a piezoelectric energy harvester,this research compares the results from the proposed method to those from the conventional strongly coupled partitioned iterative method,discussing the accuracy,stability,and computational cost.The proposed hybrid concept is effective for coupled multi-physics problems,including various coupling conditions. 展开更多
关键词 Structure-piezoelectric-circuit interaction energy harvesting partitioned method monolithic method hybrid method
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Use of artificial intelligence in total mesorectal excision in rectal cancer surgery: State of the art and perspectives
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作者 Vinicio Mosca Giacomo Fuschillo +3 位作者 Guido Sciaudone Kapil Sahnan Francesco Selvaggi Gianluca Pellino 《Artificial Intelligence in Gastroenterology》 2023年第3期64-71,共8页
BACKGROUND Colorectal cancer is a major public health problem,with 1.9 million new cases and 953000 deaths worldwide in 2020.Total mesorectal excision(TME)is the standard of care for the treatment of rectal cancer and... BACKGROUND Colorectal cancer is a major public health problem,with 1.9 million new cases and 953000 deaths worldwide in 2020.Total mesorectal excision(TME)is the standard of care for the treatment of rectal cancer and is crucial to prevent local recurrence,but it is a technically challenging surgery.The use of artificial intelligence(AI)could help improve the performance and safety of TME surgery.AIM To review the literature on the use of AI and machine learning in rectal surgery and potential future developments.METHODS Online scientific databases were searched for articles on the use of AI in rectal cancer surgery between 2020 and 2023.RESULTS The literature search yielded 876 results,and only 13 studies were selected for review.The use of AI in rectal cancer surgery and specifically in TME is a rapidly evolving field.There are a number of different AI algorithms that have been developed for use in TME,including algorithms for instrument detection,anatomical structure identification,and image-guided navigation systems.CONCLUSION AI has the potential to revolutionize TME surgery by providing real-time surgical guidance,preventing complic-ations,and improving training.However,further research is needed to fully understand the benefits and risks of AI in TME surgery. 展开更多
关键词 Artificial intelligence Machine learning Rectal cancer Total mesorectal excision Colorectal surgery
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A High-Accuracy Curve Boundary Recognition Method Based on the Lattice Boltzmann Method and Immersed Moving Boundary Method
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作者 Jie-Di Weng Yong-Zheng Jiang +2 位作者 Long-Chao Chen Xu Zhang Guan-Yong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2533-2557,共25页
Applying numerical simulation technology to investigate fluid-solid interaction involving complex curved bound-aries is vital in aircraft design,ocean,and construction engineering.However,current methods such as Latti... Applying numerical simulation technology to investigate fluid-solid interaction involving complex curved bound-aries is vital in aircraft design,ocean,and construction engineering.However,current methods such as Lattice Boltzmann(LBM)and the immersion boundary method based on solid ratio(IMB)have limitations in identifying custom curved boundaries.Meanwhile,IBM based on velocity correction(IBM-VC)suffers from inaccuracies and numerical instability.Therefore,this study introduces a high-accuracy curve boundary recognition method(IMB-CB),which identifies boundary nodes by moving the search box,and corrects the weighting function in LBM by calculating the solid ratio of the boundary nodes,achieving accurate recognition of custom curve boundaries.In addition,curve boundary image and dot methods are utilized to verify IMB-CB.The findings revealed that IMB-CB can accurately identify the boundary,showing an error of less than 1.8%with 500 lattices.Also,the flow in the custom curve boundary and aerodynamic characteristics of the NACA0012 airfoil are calculated and compared to IBM-VC.Results showed that IMB-CB yields lower lift and drag coefficient errors than IBM-VC,with a 1.45%drag coefficient error.In addition,the characteristic curve of IMB-CB is very stable,whereas that of IBM-VC is not.For the moving boundary problem,LBM-IMB-CB with discrete element method(DEM)is capable of accurately simulating the physical phenomena of multi-moving particle flow in complex curved pipelines.This research proposes a new curve boundary recognition method,which can significantly promote the stability and accuracy of fluid-solid interaction simulations and thus has huge applications in engineering. 展开更多
关键词 Fluid-solid interaction curve boundary recognition method Lattice Boltzmann method immersed moving boundary method
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