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Chyle leak following root of mesentery dissection in pancreaticoduodenectomy with inferior infracolic superior mesenteric artery first approach
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作者 Prabir Maharjan Sujan Regmee +5 位作者 Spandan D Adhikari Rabin Pahari Roshan Ghimire Dhiresh K Maharjan Suman K Shrestha Prabin B Thapa 《World Journal of Clinical Cases》 SCIE 2025年第8期8-14,共7页
BACKGROUND The root of mesentery dissection is one of the critical maneuvers,especially in borderline resectable pancreatic head cancer.Intra-abdominal chyle leak(CL)including chylous ascites may ensue in up to 10%of ... BACKGROUND The root of mesentery dissection is one of the critical maneuvers,especially in borderline resectable pancreatic head cancer.Intra-abdominal chyle leak(CL)including chylous ascites may ensue in up to 10%of patients after pancreatic resections.Globally recognized superior mesenteric artery(SMA)first approaches are invariably performed.The mesenteric dissection through the inferior infracolic approach has been discussed in this study emphasizing its post-operative impact on CL which is the cornerstone of this study.AIM To assess incidence,risk factors,clinical impact of CL following root of mesentery dissection,and the different treatment modalities.METHODS This is a retrospective study incorporating the patients who underwent dissection of the root of mesentery with inferior infracolic SMA first approach pancreat-oduodenectomy for the ventral body and uncinate mass of pancreas in the Department of Gastrointestinal and General Surgery of Kathmandu Medical College and Teaching Hospital from January 1,2021 to February 28,2024.Intraop-erative findings and postoperative outcomes were analyzed.RESULTS In three years,ten patients underwent root of mesentery dissection with inferior infracolic SMA first approach pancreatoduodenectomy.The mean age was 67.6 years with a male-to-female ratio of 4:5.CL was seen in four patients.With virtue of CL,Clavien-Dindo grade Ⅱ or higher morbidity was observed in four patients.Two patients had a hospital stay of more than 20 days with the former having a delayed gastric emptying and the latter with long-term total parenteral nutrition requirement.The mean operative time was 330 minutes.Curative resection was achieved in 100%of the patients.The mean duration of the intensive care unit and hospital stay were 2.55±1.45 days and 15.7±5.32 days,respectively.CONCLUSION Root of mesentery dissection with lymphadenectomy and vascular resection correlated with occurrence of CL.After complete curative resection,these were managed with total parenteral nutrition without adversely impacting outcome. 展开更多
关键词 Chyle leak Chylous ascites Clavien-Dindo Pancreatoduodenectomy Root of mesentery dissection Superior mesenteric artery first approach Total parenteral nutrition Uncinate mass Vascular resection Ventral body mass
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Obesity paradox in patients with community-acquired pneumonia:Have you fully considered the confounding factors?
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作者 Jin-Ke Sun Hui Tian 《World Journal of Clinical Cases》 SCIE 2025年第9期53-55,共3页
There exists a notion that there is an obesity paradox in the prognosis of community-acquired pneumonia.In other words,obese individuals with communityacquired pneumonia have a better prognosis.The study by Wang et al... There exists a notion that there is an obesity paradox in the prognosis of community-acquired pneumonia.In other words,obese individuals with communityacquired pneumonia have a better prognosis.The study by Wang et al supports this claim,but we believe that the obesity paradox should not be proposed hastily as it is influenced by numerous subjective and objective confounding factors. 展开更多
关键词 Community-acquired pneumonia MORTALITY Body mass index OVERWEIGHT Obesity paradox
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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator 被引量:1
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作者 Yang Zhang Sheng-Quan Yan +36 位作者 Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期136-143,共8页
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides... The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated. 展开更多
关键词 Accelerator mass spectrometry Wien filter Isobar separation SUPERNOVAE Chang'e-5 lunar samples
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TRIANGLE operation,combined with adequate adjuvant chemotherapy,can improve the prognosis of pancreatic head cancer:A retrospective study
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作者 Jia-Hao Chen Li-Yong Zhu +7 位作者 Zhi-Wei Cai Xiao Hu Abousalam Abdoulkader Ahmed Jie-Qiong Ge Xiao-Yan Tang Chun-Jing Li Yun-Long Pu Chong-Yi Jiang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1773-1786,共14页
BACKGROUND The TRIANGLE operation involves the removal of all tissues within the triangle bounded by the portal vein-superior mesenteric vein,celiac axis-common hepatic artery,and superior mesenteric artery to improve... BACKGROUND The TRIANGLE operation involves the removal of all tissues within the triangle bounded by the portal vein-superior mesenteric vein,celiac axis-common hepatic artery,and superior mesenteric artery to improve patient prognosis.Although previously promising in patients with locally advanced pancreatic ductal adenocarcinoma(PDAC),data are limited regarding the long-term oncological outcomes of the TRIANGLE operation among resectable PDAC patients undergoing pancreaticoduodenectomy(PD).AIM To evaluate the safety of the TRIANGLE operation during PD and the prognosis in patients with resectable PDAC.METHODS This retrospective cohort study included patients who underwent PD for pancreatic head cancer between January 2017 and April 2023,with or without the TRIANGLE operation.Patients were divided into the PD_(TRIANGLE)and PD_(non-TRIANGLE)groups.Surgical and survival outcomes were compared between the two groups.Adequate adjuvant chemotherapy was defined as adjuvant chemotherapy≥6 months.RESULTS The PD_(TRIANGLE)and PD_(non-TRIANGLE) groups included 52 and 55 patients,respectively.There were no significant differences in the baseline characteristics or perioperative indexes between the two groups.Furthermore,the recurrence rate was lower in the PD_(TRIANGLE) group than in the PD_(non-TRIANGLE) group(48.1%vs 81.8%,P<0.001),and the local recurrence rate of PDAC decreased from 37.8%to 16.0%.Multivariate Cox regression analysis revealed that PD_(TRIANGLE)(HR=0.424;95%CI:0.256-0.702;P=0.001),adequate adjuvant chemotherapy≥6 months(HR=0.370;95%CI:0.222-0.618;P<0.001)and margin status(HR=2.255;95%CI:1.252-4.064;P=0.007)were found to be independent factors for the recurrence rate.CONCLUSION The TRIANGLE operation is safe for PDAC patients undergoing PD.Moreover,it reduces the local recurrence rate of PDAC and may improve survival in patients who receive adequate adjuvant chemotherapy. 展开更多
关键词 triangle operation Pancreatic ductal adenocarcinoma Heidelberg triangle Adjuvant chemotherapy PROGNOSIS PANCREATICODUODENECTOMY
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Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions
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作者 Xue-Ping Du Guang-Lei Yu +3 位作者 Ya-Cheng Xu Zhi-Jie Chen Nai-Liang Li Huan-Guang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1333-1345,共13页
The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper stud... The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure drop.These results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions. 展开更多
关键词 Spiral-wound heat exchanger Sloshing conditions Two-phase flow MULTI-COMPONENT Heat and mass transfer
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Low skeletal muscle mass and high visceral adiposity are associated with recurrence of acute cholecystitis after conservative management:A propensity score-matched cohort study
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作者 Yudai Koya Michihiko Shibata +5 位作者 Yuki Maruno Yoshitaka Sakamoto Shinji Oe Koichiro Miyagawa Yuichi Honma Masaru Harada 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第1期64-70,共7页
Background:Recurrent acute cholecystitis(RAC)can occur after non-surgical treatment for acute cholecystitis(AC),and can be more severe in comparison to the first episode of AC.Low skeletal muscle mass or adiposity hav... Background:Recurrent acute cholecystitis(RAC)can occur after non-surgical treatment for acute cholecystitis(AC),and can be more severe in comparison to the first episode of AC.Low skeletal muscle mass or adiposity have various effects in several diseases.We aimed to clarify the relationship between RAC and body parameters.Methods:Patients with AC who were treated at our hospital between January 2011 and March 2022 were enrolled.The psoas muscle mass and adipose tissue area at the third lumbar level were measured using computed tomography at the first episode of AC.The areas were divided by height to obtain the psoas muscle mass index(PMI)and subcutaneous/visceral adipose tissue index(SATI/VATI).According to median VATI,SATI and PMI values by sex,patients were divided into the high and low PMI groups.We performed propensity score matching to eliminate the baseline differences between the high PMI and low PMI groups and analyzed the cumulative incidence and predictors of RAC.Results:The entire cohort was divided into the high PMI(n=81)and low PMI(n=80)groups.In the propensity score-matched cohort there were 57 patients in each group.In Kaplan-Meier analysis,the low PMI group and the high VATI group had a significantly higher cumulative incidence of RAC than their counterparts(log-rank P=0.001 and 0.015,respectively).In a multivariate Cox regression analysis,the hazard ratios of low PMI and low VATI for RAC were 5.250(95%confidence interval 1.083-25.450,P=0.039)and 0.158(95%confidence interval:0.026-0.937,P=0.042),respectively.Conclusions:Low skeletal muscle mass and high visceral adiposity were independent risk factors for RAC. 展开更多
关键词 Acute cholecystitis Low skeletal muscle mass Recurrent acute cholecystitis SARCOPENIA Visceral adiposity
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Structural engineering of Fe single-atom oxygen reduction catalyst with high site density and improved mass transfer
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作者 Jiawen Wu Yuanzhi Zhu +3 位作者 An Cai Xiaobin Fan Wenchao Peng Yang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期634-644,共11页
Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges re... Fe-N-C catalysts are widely considered as promising non-precious-metal candidates for electrocatalytic oxygen reduction reaction(ORR),Yet despite their high catalytic activity through rational modulation,challenges remain in their low site density and unsatisfactory mass transfer structure.Herein,we present a structural engineering approach employing a soft-template coating strategy to fabricate a hollow and hierarchically porous N-doped carbon framework anchored with atomically dispersed Fe sites(FeNCh) as an efficient ORR catalyst.The combination of hierarchical porosity and high exterior surface area is proven crucial for exposing more active sites,which gives rise to a remarkable ORR performance with a half-wave potential of 0.902 V in 0.1 m KOH and 0.814 V in 0.1 m HClO_(4),significantly outperforming its counterpart with solid structure and dominance of micropores(FeNC-s).The mass transfer property is revealed by in-situ electrochemical impedance spectroscopy(EIS) measurement.The distribution of relaxation time(DRT) analysis is further introduced to deconvolve the kinetic and mass transport processes,which demonstrates an alleviated mass transport resistance for FeNC-h,validating the effectiveness of structural engineering.This work not only provides an effective structural engineering approach but also contributes to the comprehensive mass transfer evaluation on advanced electrocatalyst for energy conversion applications. 展开更多
关键词 Single-atom catalysts Oxygen reduction reaction Structural engineering Active site density mass transfer Zinc-air batteries
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Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient
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作者 Zheng Lichang Xu Guoshan +3 位作者 Yang Ge Wang Zhen Yang Kaibo Zheng Zhenyun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期625-636,共12页
For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated.Therefore,this study prop... For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated.Therefore,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation coefficient.First,the theory of the CDM for RTDST is presented.Next,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are investigated.Finally,numerical simulations and experimental tests are conducted for verifying the effectiveness of the method.The study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient increases.In most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its stability.The stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper. 展开更多
关键词 real-time dynamic substructure testing central difference method STABILITY mass participation coefficient tuned liquid damper
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Failure behavior and strength model of blocky rock mass with and without rockbolts
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作者 Chun Zhu Xiansen Xing +4 位作者 Manchao He Zhicheng Tang Feng Xiong Zuyang Ye Chaoshui Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期747-762,共16页
To better understand the failure behaviours and strength of bolt-reinforced blocky rocks,large scale extensive laboratory experiments are carried out on blocky rock-like specimens with and without rockbolt reinforceme... To better understand the failure behaviours and strength of bolt-reinforced blocky rocks,large scale extensive laboratory experiments are carried out on blocky rock-like specimens with and without rockbolt reinforcement.The results show that both shear failure and tensile failure along joint surfaces are observed but the shear failure is a main controlling factor for the peak strength of the rock mass with and without rockbolts.The rockbolts are necked and shear deformation simultaneously happens in bolt reinforced rock specimens.As the joint dip angle increases,the joint shear failure becomes more dominant.The number of rockbolts has a significant impact on the peak strain and uniaxial compressive strength(UCS),but little influence on the deformation modulus of the rock mass.Using the Winkler beam model to represent the rockbolt behaviours,an analytical model for the prediction of the strength of boltreinforced blocky rocks is proposed.Good agreement between the UCS values predicted by proposed model and obtained from experiments suggest an encouraging performance of the proposed model.In addition,the performance of the proposed model is further assessed using published results in the literature,indicating the proposed model can be used effectively in the prediction of UCS of bolt-reinforced blocky rocks. 展开更多
关键词 Blocky rock mass Rockbolt ground support Uniaxial compression test Failure mechanism Uniaxial compressive strength model
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Lean body mass index is a marker of advanced tumor features in patients with hepatocellular carcinoma
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作者 Andrew Scott deLemos Jing Zhao +9 位作者 Milin Patel Banks Kooken Karan Mathur Hieu Minh Nguyen Areej Mazhar Maggie McCarter Heather Burney Carla Kettler Naga Chalasani Samer Gawrieh 《World Journal of Hepatology》 2024年第3期393-404,共12页
BACKGROUND Obesity is an independent risk factor for the development of hepatocellular carcinoma(HCC)and may influence its outcomes.However,after diagnosis of HCC,like other malignancies,the obesity paradox may exist ... BACKGROUND Obesity is an independent risk factor for the development of hepatocellular carcinoma(HCC)and may influence its outcomes.However,after diagnosis of HCC,like other malignancies,the obesity paradox may exist where higher body mass index(BMI)may in fact confer a survival benefit.This is frequently observed in patients with advanced HCC and cirrhosis,who often present late with advanced tumor features and cancer related weight loss.AIM To explore the relationship between BMI and survival in patients with cirrhosis and HCC.METHODS This is a retrospective cohort study of over 2500 patients diagnosed with HCC between 2009-2019 at two United States academic medical centers.Patient and tumor characteristics were extracted manually from medical records of each institutions'cancer registries.Patients were stratified according to BMI classes:<25 kg/m^(2)(lean),25-29.9 kg/m^(2)(overweight),and>30 kg/m^(2)(obese).Patient and tumor characteristics were compared according to BMI classification.We performed an overall survival analysis using Kaplan Meier by the three BMI classes and after adjusting for Milan criteria.A multivariable Cox regression model was then used to assess known risk factors for survival in patients with cirrhosis and HCC.RESULTS A total of 2548 patients with HCC were included in the analysis of which 11.2%(n=286)were classified as noncirrhotic.The three main BMI categories:Lean(n=754),overweight(n=861),and obese(n=933)represented 29.6%,33.8%,and 36.6%of the total population overall.Within each BMI class,the non-cirrhotic patients accounted for 15%(n=100),12%(n=94),and 11%(n=92),respectively.Underweight patients with a BMI<18.5 kg/m^(2)(n=52)were included in the lean cohort.Of the obese cohort,42%(n=396)had a BMI≥35 kg/m^(2).Out of 2262 patients with cirrhosis and HCC,654(29%)were lean,767(34%)were overweight,and 841(37%)were obese.The three BMI classes did not differ by age,MELD,or Child-Pugh class.Chronic hepatitis C was the dominant etiology in lean compared to the overweight and obese patients(71%,62%,49%,P<0.001).Lean patients had significantly larger tumors compared to the other two BMI classes(5.1 vs 4.2 vs 4.2 cm,P<0.001),were more likely outside Milan(56%vs 48%vs 47%,P<0.001),and less likely to undergo transplantation(9%vs 18%vs 18%,P<0.001).While both tumor size(P<0.0001)and elevated alpha fetoprotein(P<0.0001)were associated with worse survival by regression analysis,lean BMI was not(P=0.36).CONCLUSION Lean patients with cirrhosis and HCC present with larger tumors and are more often outside Milan criteria,reflecting cancer related cachexia from delayed diagnosis.Access to care for hepatitis C virus therapy and liver transplantation confer a survival benefit,but not overweight or obese BMI classifications. 展开更多
关键词 Hepatocellular carcinoma CIRRHOSIS OBESITY Body mass index class SARCOPENIA Chronic hepatitis C
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A Study on the Correlation of Body Mass Management During Pregnancy with Adverse Pregnancy Outcomes and Labor Progression
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作者 Ying Zhou Lijun Song 《Journal of Clinical and Nursing Research》 2024年第5期56-61,共6页
Objective:To investigate the effects of body mass management during pregnancy on adverse pregnancy outcomes,duration of labor,and neonatal birth weight.Methods:472 pregnant women who visited Beijing Anzhen Hospital fr... Objective:To investigate the effects of body mass management during pregnancy on adverse pregnancy outcomes,duration of labor,and neonatal birth weight.Methods:472 pregnant women who visited Beijing Anzhen Hospital from January to December 2023 were selected,and the pregnant women were divided into 236 each in the observation group and the control group.Body mass of pregnant women was measured and BMI was calculated in early and late pregnancy respectively,and the pregnant women in the control group were guided by routine management,while the observation group was guided by body mass management during pregnancy.The growth of maternal body mass,mode of delivery,postpartum hemorrhage,neonatal score,neonatal blood glucose at birth,and umbilical artery blood,as well as the comparison of the duration of labor,were observed.Results:The observation group was significantly better than the control group in terms of mode of delivery,postpartum hemorrhage,and body mass growth,with statistically significant differences(P<0.05),and there was no statistical significance in terms of neonatal scores,neonatal blood glucose at birth,and umbilical artery blood(P>0.05);the time of the first stage of labor and the time of the second stage of labor of the mothers in the observation group was significantly better than that of the control group,with statistical differences(P<0.05),and the time of the third stage of labor of the mothers in the observation group was statistically better than that of the control group.There was no statistically significant difference between the time of the third stage of labor in the observation group and the control group(P>0.05),and the time of the total stage of labor in the observation group was statistically better than that in the control group(P<0.05).Conclusion:Body mass management during pregnancy can effectively improve maternal control of weight gain,reduce labor time,and decrease the occurrence of adverse pregnancy outcomes. 展开更多
关键词 PREGNANCY Body mass management Adverse pregnancy outcome Labor duration
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Simulation of coupled flowing-reaction-deformation with mass transfer in heap leaching processes 被引量:2
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作者 吴爱祥 刘金枝 唐玲艳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第3期327-335,共9页
Governing equations for a fully coupled flowing-reaction-deformation behavior with mass transfer in heap leaching are developed. The model equations are solved using an explicit finite difference method under the cond... Governing equations for a fully coupled flowing-reaction-deformation behavior with mass transfer in heap leaching are developed. The model equations are solved using an explicit finite difference method under the conditions of invariable application rate and constant hydraulic head. The distribution of the degree of the saturation, as well as the distributions of the concentration of the reagent and the solute is given. A cubic relationship between the mineral recovery and the leaching duration is obtained based on the numerical results. The relationship can be used to predict the recovery percentage of the valuable metal. 展开更多
关键词 heap leaching porosity evolution model saturation degree mass transfer numerical solution
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Peristaltic Transport of Magnetohydrodynamic Carreau Nanofluid with Heat and Mass Transfer inside Asymmetric Channel
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作者 Nabil T. M. Eldabe Osama M. Abo-Seida +2 位作者 Adel A. S. Abo-Seliem A. A. ElShekhipy Nada Hegazy 《American Journal of Computational Mathematics》 2017年第1期1-20,共20页
In this work, the peristaltic motion of a nano non-Newtonian fluid which obeys Carreau model through a porous medium inside an asymmetric channel is investigated. The hall current effects with Joule heating and viscou... In this work, the peristaltic motion of a nano non-Newtonian fluid which obeys Carreau model through a porous medium inside an asymmetric channel is investigated. The hall current effects with Joule heating and viscous dissipation are considered. The problem is modulated mathematically by a set of nonlinear partial differential equations which describe the conservation of mass, momentum, energy and concentration of nanoparticles. The non-dimensional form of these equations is simplified under the assumption of long wavelength and low Reynolds number, and then resulting equations of coupled nonlinear differential equations are tackled numerically with appropriate boundary conditions. Graphical results are presented for dimensionless velocity, temperature, concentration and pressure gradient in order to illustrate the variations of various parameters of this problem on these obtained solutions. 展开更多
关键词 Peristaltic Motion MHD Carreau NANofLUID ASYMMETRIC Channel POROUS Medium Heat and mass Transfer
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Damage failure of cemented backfill and its reasonable match with rock mass 被引量:31
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作者 刘志祥 兰明 +1 位作者 肖思友 郭虎强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期954-959,共6页
In order to study the failure mechanism of backfill and the reasonable matches between backfill and rock mass, and to achieve the object of safe and efficient mining in metal mine, four types of backfills were tested ... In order to study the failure mechanism of backfill and the reasonable matches between backfill and rock mass, and to achieve the object of safe and efficient mining in metal mine, four types of backfills were tested under uniaxial compression loading, with cement?tailing ratios of 0.250:1, 0.125:1, 0.100:1 and 0.083:1, respectively. With the help of the stress?strain curves, the deformation and failure characteristics of different backfills with differing cement?tailing ratios were analyzed. Based on the experimental results, the damage constitutive equations of cemented backfills with four cement?tailing ratios were proposed on the basis of damage mechanics. Moreover, comparative analysis of constitutive model and experimental results were made to verify the reliability of the damage model. In addition, an energy model using catastrophe theory to obtain the instability criteria of system was established to study the interaction between backfill and rock mass, and then the system instability criterion was deduced. The results show that there are different damage characteristics for different backfills, backfills with lower cement?tailing ratio tend to have a lower damage value when stress reaches peak value, and damage more rapidly and more obviously in failure process after peak value of stress; the stiffness and elastic modulus of rock mass with lower strength are more likely to lead to system instability. The results of this work provide a scientific basis for the rational strength design of backfill mine. 展开更多
关键词 cemented tailings backfill rock mass damage constitutive equation catastrophe theory MATCH instability criterion
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Tricuspid mass-curious case of Li-Fraumeni syndrome: A case report 被引量:6
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作者 Tyler Huffaker Stella Pak +1 位作者 Anum Asif Prince Otchere 《World Journal of Clinical Cases》 SCIE 2024年第11期1936-1939,共4页
BACKGROUND Li-Fraumeni syndrome(LFS)is a rare autosomal dominant cancer-predisposing syndrome,which can manifest as a polymorphic spectrum of malignancies.LFS is associated with an early onset in life,with the majorit... BACKGROUND Li-Fraumeni syndrome(LFS)is a rare autosomal dominant cancer-predisposing syndrome,which can manifest as a polymorphic spectrum of malignancies.LFS is associated with an early onset in life,with the majority of cases occurring prior to the age of 46.Notwithstanding the infrequency of primary cardiac tumors,it behooves clinicians to remain vigilant in considering the differential diagnosis of such tumors in LFS patients who present with a cardiac mass.This is due to the markedly elevated risk for malignancy in this particular population,far surpassing that of the general populace.CASE SUMMARY Herein,we present a case of a 30-year-old female with LFS who was found to have a tricuspid valve leaflet mass.CONCLUSION This case exemplifies valuable learning points in the diagnostic approach for this exceptionally rare patient population. 展开更多
关键词 Li-Fraumeni syndrome Cardiac mass Intracardiac thrombus Transesophageal echocardiogram Cardiac magnetic resonance imaging Case report
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Evaluation of slope stability through rock mass classification and kinematic analysis of some major slopes along NH-1A from Ramban to Banihal, North Western Himalayas 被引量:2
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作者 Amit Jaiswal A.K.Verma T.N.Singh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期167-182,共16页
The network of Himalayan roadways and highways connects some remote regions of valleys or hill slopes,which is vital for India’s socio-economic growth.Due to natural and artificial factors,frequency of slope instabil... The network of Himalayan roadways and highways connects some remote regions of valleys or hill slopes,which is vital for India’s socio-economic growth.Due to natural and artificial factors,frequency of slope instabilities along the networks has been increasing over last few decades.Assessment of stability of natural and artificial slopes due to construction of these connecting road networks is significant in safely executing these roads throughout the year.Several rock mass classification methods are generally used to assess the strength and deformability of rock mass.This study assesses slope stability along the NH-1A of Ramban district of North Western Himalayas.Various structurally and non-structurally controlled rock mass classification systems have been applied to assess the stability conditions of 14 slopes.For evaluating the stability of these slopes,kinematic analysis was performed along with geological strength index(GSI),rock mass rating(RMR),continuous slope mass rating(CoSMR),slope mass rating(SMR),and Q-slope in the present study.The SMR gives three slopes as completely unstable while CoSMR suggests four slopes as completely unstable.The stability of all slopes was also analyzed using a design chart under dynamic and static conditions by slope stability rating(SSR)for the factor of safety(FoS)of 1.2 and 1 respectively.Q-slope with probability of failure(PoF)1%gives two slopes as stable slopes.Stable slope angle has been determined based on the Q-slope safe angle equation and SSR design chart based on the FoS.The value ranges given by different empirical classifications were RMR(37-74),GSI(27.3-58.5),SMR(11-59),and CoSMR(3.39-74.56).Good relationship was found among RMR&SSR and RMR&GSI with correlation coefficient(R 2)value of 0.815 and 0.6866,respectively.Lastly,a comparative stability of all these slopes based on the above classification has been performed to identify the most critical slope along this road. 展开更多
关键词 Rock mass classification Kinematic analysis Slope stability Himalayan road Static and dynamic conditions
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Probabilistic analysis of tunnel face seismic stability in layered rock masses using Polynomial Chaos Kriging metamodel 被引量:2
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作者 Jianhong Man Tingting Zhang +1 位作者 Hongwei Huang Daniel Dias 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2678-2693,共16页
Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines... Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines the Upper bound Limit analysis of Tunnel face stability,the Polynomial Chaos Kriging,the Monte-Carlo Simulation and Analysis of Covariance method(ULT-PCK-MA),is proposed to investigate the seismic stability of tunnel faces.A two-dimensional analytical model of ULT is developed to evaluate the virtual support force based on the upper bound limit analysis.An efficient probabilistic analysis method PCK-MA based on the adaptive Polynomial Chaos Kriging metamodel is then implemented to investigate the parameter uncertainty effects.Ten input parameters,including geological strength indices,uniaxial compressive strengths and constants for three rock formations,and the horizontal seismic coefficients,are treated as random variables.The effects of these parameter uncertainties on the failure probability and sensitivity indices are discussed.In addition,the effects of weak layer position,the middle layer thickness and quality,the tunnel diameter,the parameters correlation,and the seismic loadings are investigated,respectively.The results show that the layer distributions significantly influence the tunnel face probabilistic stability,particularly when the weak rock is present in the bottom layer.The efficiency of the proposed ULT-PCK-MA is validated,which is expected to facilitate the engineering design and construction. 展开更多
关键词 Tunnel face stability Layered rock masses Polynomial Chaos Kriging(PCK) Sensitivity index Seismic loadings
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Probabilistic assessment of tunnel convergence considering spatial variability in rock mass properties using interpolated autocorrelation and response surface method 被引量:14
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作者 Qing Lü Zhipeng Xiao +1 位作者 Jun Zheng Yuequan Shang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1619-1629,共11页
This study aims at the probabilistic assessment of tunnel convergence considering the spatial variability in rock mass properties. The method of interpolated autocorrelation combined with finite difference analysis is... This study aims at the probabilistic assessment of tunnel convergence considering the spatial variability in rock mass properties. The method of interpolated autocorrelation combined with finite difference analysis is adopted to model the spatial variability of rock mass properties. An iterative procedure using the first-order reliability method(FORM) and response surface method(RSM) is employed to compute the reliability index and its corresponding design point. The results indicate that the spatial variability considerably affects the computed reliability index. The probability of failure could be noticeably overestimated in the case where the spatial variability is neglected. The vertical scale of fluctuation has a much higher effect on the probabilistic result with respect to the tunnel convergence than the horizontal scale of fluctuation. And the influence of different spacing of control points on the computational accuracy is investigated. 展开更多
关键词 Spatial VARIABILITY ROCK mass TUNNEL CONVERGENCE FORM Random field
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Planar System-Masses in an Equilateral Triangle:Numerical Study within Fractional Calculus 被引量:5
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作者 Dumitru Baleanu Behzad Ghanbari +2 位作者 Jihad H.Asad Amin Jajarmi Hassan Mohammadi Pirouz 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期953-968,共16页
In this work,a system of three masses on the vertices of equilateral triangle is investigated.This system is known in the literature as a planar system.We first give a description to the system by constructing its cla... In this work,a system of three masses on the vertices of equilateral triangle is investigated.This system is known in the literature as a planar system.We first give a description to the system by constructing its classical Lagrangian.Secondly,the classical Euler-Lagrange equations(i.e.,the classical equations of motion)are derived.Thirdly,we fractionalize the classical Lagrangian of the system,and as a result,we obtain the fractional Euler-Lagrange equations.As the final step,we give the numerical simulations of the fractional model,a new model which is based on Caputo fractional derivative. 展开更多
关键词 Planar system masses in equilateral triangle SPRINGS Euler-Lagrange equations fractional derivative
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Rock mass quality prediction on tunnel faces with incomplete multi-source dataset via tree-augmented naive Bayesian network 被引量:1
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作者 Hongwei Huang Chen Wu +3 位作者 Mingliang Zhou Jiayao Chen Tianze Han Le Zhang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期323-337,共15页
Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantita... Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantitative parameters.However,due to the harsh on-site construction conditions,it is rather difficult to obtain some of the evaluation parameters which are essential for the rock mass quality prediction.In this study,a novel improved Swin Transformer is proposed to detect,segment,and quantify rock mass characteristic parameters such as water leakage,fractures,weak interlayers.The site experiment results demonstrate that the improved Swin Transformer achieves optimal segmentation results and achieving accuracies of 92%,81%,and 86%for water leakage,fractures,and weak interlayers,respectively.A multisource rock tunnel face characteristic(RTFC)dataset includes 11 parameters for predicting rock mass quality is established.Considering the limitations in predictive performance of incomplete evaluation parameters exist in this dataset,a novel tree-augmented naive Bayesian network(BN)is proposed to address the challenge of the incomplete dataset and achieved a prediction accuracy of 88%.In comparison with other commonly used Machine Learning models the proposed BN-based approach proved an improved performance on predicting the rock mass quality with the incomplete dataset.By utilizing the established BN,a further sensitivity analysis is conducted to quantitatively evaluate the importance of the various parameters,results indicate that the rock strength and fractures parameter exert the most significant influence on rock mass quality. 展开更多
关键词 Rock mass quality Tunnel faces Incomplete multi-source dataset Improved Swin Transformer Bayesian networks
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