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Fracture sealing performance of granular lost circulation materials at elevated temperature:A theoretical and coupled CFD-DEM simulation study

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Petroleum Science 2024年第1期21卷 567-581页

作者： Chong Lin Qi-Cong Xu Lie-Xiang Han Gao Li hai he Hong-Ling Zhou Ji-Ping She CCDC Drilling&Production Technology Research Institute Guanghan618300SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina College of Materials Science and Engineering Chongqing UniversityChongqing400044China State Key Lab of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology) Chengdu610059SichuanChina College of Energy Chengdu University of TechnologyChengdu610059SichuanChina

Lost circulation is a common downhole problem of drilling in geothermal and high-temperature,high-pressure(HTHP)*** circulation material(LCM)is a regular preventive and remedial measure for lost ***,conventional LCMs seem ineffective in high-temperature *** may be due to the changes in the mechanical properties of LCMs and their sealing performance under high-temperature *** understand how high temperature affects the fracture sealing performance of LCMs,we developed a coupled computational fluid dynamics-discrete element method(CFD-DEM)model to simulate the behavior of granular LCMs in *** summarized the literature on the effects of high temperature on the mechanical properties of LCMs and the rheological properties of drilling *** conducted sensitivity analyses to investigate how changing LCM slurry properties affected the fracture sealing efficiency at increasing *** results show that high temperature reduces the size,strength,and friction coefficient of LCMs as well as the drilling fluid ***,softer,and less frictional LCM particles have lower bridging probability and slower bridging *** particles tend to form dual-particle bridges rather than single-particle *** result in a deeper,tighter,but unstable sealing *** drilling fluid viscosity leads to faster and shallower sealing zones.

关键词： Geothermal well drilling HTHP formationLost circulation material CFD-DEM Fracture sealing

Effect of the extrahepatic bile duct anatomy on choledocholithiasis and its clinical significance

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1363-1370页

作者： Zheng Cao Jia Zhou Li Wei hai-Yu he Jun Li Department of Gastroenterology The Second Affiliated Hospital of Kunming Medical UniversityKunming 650000Yunnan ProvinceChina

BACKGROUND A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde *** irregularities within the extrahepatic bile duct may increase susceptibility to bile duct *** To investigate the anatomical risk factors associated with extrahepatic bile ducts in patients diagnosed with choledocholithiasis,with a specific focus on preventing stone recurrence after surgical intervention and endoscopic *** We retrospectively analyzed the medical records of 124 patients without choledocholithiasis and 108 with confirmed choledocholithiasis who underwent magnetic resonance cholangiopancreatography examinations at our center between January 2022 and October *** regression analyses were conducted to identify the anatomical risk factors influencing the incidence of common bile duct *** Multivariate logistic regression analysis revealed that several factors independently contributed to choledocholithiasis *** independent risk factors for choledocholithiasis were diameter of the common hepatic[adjusted odds ratio(aOR)=1.43,95%confidence interval(CI):1.07-1.92,adjusted P value=0.016]and common bile(aOR=1.68,95%CI:1.27-2.23,adjusted P valuehe common hepatic duct(aOR=0.92,95%CI:0.84-0.99,adjusted P value=0.034),and angle of the common bile duct(aOR=0.92,95%CI:0.89–0.95,adjusted P valuehe anatomical features of the extrahepatic bile duct were directly associated with choledocholithiasis *** risk factors include an enlarged diameter of the common hepatic and bile ducts,a shorter length of the common hepatic duct,and a reduced angle of the common bile duct.

关键词： Bile ducts Extrahepatic Choledocholithiasis Cholangiopancreatography Magnetic resonance Cholangiopancreatography Endoscopic retrograde

Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 852-860页

作者： hai-Jian Hu Ping Li Bin Tong Yu-Lian Pang Hong-Dou Luo Fei-Fei Wang Chan Xiong Yu-Lin Yu hai he Xu Zhang Affiliated Eye Hospital of Nanchang University Jiangxi Research Institute of Ophthalmology and Visual ScienceJiangxi Clinical Research Center for Ophthalmic DiseaseJiangxi Branch of National Clinical Research Center for Ocular DiseasesNanchang 330006Jiangxi ProvinceChina Wuhan Children’s Hospital(Wuhan Maternal and Child healthcare Hospital) Tongji Medical CollegeHuazhong University of Science&TechnologyWuhan 430015Hubei ProvinceChina

AIM:To assess the performance of macular ganglion cell-inner plexiform layer thickness(mGCIPLT)and 10-2 visual field(VF)parameters in detecting early glaucoma and evaluating the severity of advanced ***:Totally 127 eyes from 89 participants(36 eyes of 19 healthy participants,45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients)were *** relationships between the optical coherence tomography(OCT)-derived parameters and VF sensitivity were *** with early glaucoma were divided into eyes with or without central 10°of the VF damages(CVFDs),and the diagnostic performances of OCT-derived parameters were ***:In early glaucoma,the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation(PSD;with average mGCIPLT:β=-0.046,95%CI,-0.067 to-0.024,Phe mGCIPLT was related to the 24-2 VF mean deviation(MD;with average mGCIPLT:β=0.397,95%CI,0.199 to 0.595,Phe minimum and superotemporal mGCIPLT,the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without *** area under the curve(AUC)of the average mGCIPLT(AUC=0.949,95%CI,0.868 to 0.982)was greater than that of the average circumpapillary retinal nerve fiber layer thickness(cpRNFLT;AUC=0.827,95%CI,0.674 to 0.918)and rim area(AUC=0.799,95%CI,0.610 to 0.907)in early glaucomatous eyes with CVFDs versus normal ***:The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF,cpRNFLT and ONH parameters,especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level.

关键词： 10-2 visual field ganglion cell-inner plexiform layer retinal nerve fiber layer thickness glaucoma

A new infrageneric classification of Gastrochilus(Orchidaceae:Epidendroideae)based on molecular and morphological data

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Plant Diversity 2024年第4期46卷 435-447页

作者： Jun-Yi Zhang Yue-Hong Cheng Min Liao Yu Feng Sen-Long Jin Ting-Mei he hai he Bo Xu China-Croatia“Belt and Road”Joint Laboratory on Biodiversity and Ecosystem Services CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan ProvinceChengdu Institute of BiologyChinese Academy of SciencesP.O.Box 416Chengdu 610041SichuanChina College of Life Sciences Chongqing Normal UniversityChongqing 401331China Wolong National Natural Reserve Administration Bureau Wenchuan 623006SichuanChina University of Chinese Academy of Sciences Beijing 100049China

Gastrochilus is an orchid genus containing 73 species of mainly epiphytic on trees or rocks in mountain forests of tropical and subtropical *** phylogenetic analyses and morphological assessments have failed to produce a well-resolved phylogeny at the infrageneric *** the present study,a new infrageneric classification of Gastrochilus is proposed based on thoroughly morphological and phylogenetic analyses based on 52 *** phylogenetic analysis divided the genus into six sections including three new sections,***,*** and *** also reinstate *** to the specific ***,two new species,*** Jun ***,***&Yue *** and *** Jun ***,***&Yue ***,are described and illustrated.A key to six sections of the genus is presented.

关键词： Gastrochilus Phylogeny Character evolution Taxonomy New species

Spatial construction of ultrasmall Pt-decorated 3D spinel oxidemodified N-doped graphene nanoarchitectures as high-efficiency methanol oxidation electrocatalysts

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Rare Metals 2024年第1期43卷 186-197页

作者： Qi Zhang Min-Min Yan Wen-Fa Du Chen-Yu Yin Jian Zhang Lu Yang Yun-Qing Kang hai-Yan he Hua-Jie Huang College of Mechanics and Materials Hohai UniversityNanjing 210098China New Energy Technology Engineering Lab of Jiangsu Province College of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023China International Center for Materials Nanoarchitectonics(WPIMANA) National Institute for Materials ScienceTsukuba 305-0044IbarakiJapan

Direct methanol fuel cell technology recently becomes the focus of both academic and engineering circles,which stimulates the exploitation and utilization of advanced electrode catalysts with high activity and long ***,we demonstrate a robust bottom-up approach to the spatial construction of three-dimensional(3D) spinel manganese-cobalt oxide-modified N-doped graphene nanoarchitectures decorated with ultrasmall Pt nanoparticles(Pt/MnCo_(2)O_(4)-NG) via a controllable selfassembly *** incorporation of MnCo_(2)O_(4)nanocrystals provides abundant hydroxyl sources to promote the oxidative removal of CO-like byproducts on Pt sites,while the existence of 3D porous N-doped graphene networks facilitates the transportation of both ions and electrons in the hybrid system,thus giving rise to remarkable synergetic coupling effects during the methanol oxidation ***,the optimized Pt/MnCo_(2)O_(4)-NG nano architecture expres ses exceptional electrocatalytic properties with a large electrochemically active surface area of 99.5 m^(2)·g^(-1),a high mass activity of1508.3 mA·mg^(-1),strong toxicity resistance and reliable long-term durability,which have obvious competitive advantages over those of conventional Pt/carbon black,Pt/carbon nano tube,Pt/graphene,and Pt/N-doped graphene catalysts with the same Pt usage.

关键词： Platinum MnCo_(2)O_(4) 3D graphene Electrocatalysts Methanol oxidation

Enhanced detection of freeze‒thaw induced landslides in Zhidoi county(Tibetan Plateau,China)with Google Earth Engine and image fusion

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Advances in Climate Change Research 2024年第3期15卷 476-489页

作者： Jia-Hui YANG Yan-Chen GAO Lang JIA Wen-Juan WANG Qing-Bai WU Francis ZVOMUYA Miles DYCK hai-Long he College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Department of Soil Science University of Manitob1Winnipeg MB R3T 2N2Canada Department of Renewable Resources University of Albert1Edmonton AB T6G 2H1Canad

Freeze‒thaw induced landslides(FTILs)in grasslands on the Tibetan Plateau are a geological disaster leading to soil *** landslides reduce biodiversity and intensify landscape fragmentation,which in turn are strengthen by the persistent climate change and increased anthropogenic ***,conventional techniques for mapping FTILs on a regional scale are impractical due to their labor-intensive,costly,and time-consuming *** study focuses on improving FTILs detection by implementing image fusion-based Google Earth Engine(GEE)and a random forest *** of multiple data sources,including texture features,index features,spectral features,slope,and vertical‒vertical polarization data,allow automatic detection of the spatial distribution characteristics of FTILs in Zhidoi county,which is located within the Qinghai‒Tibet Engineering Corridor(QTEC).We employed statistical techniques to elucidate the mechanisms influencing FTILs *** enhanced method identifies two schemes that achieve high accuracy using a smaller training sample(scheme A:94.1%;scheme D:94.5%)compared to other methods(scheme B:50.0%;scheme C:95.8%).This methodology is effective in generating accurate results using only~10%of the training sample size necessitated by other *** spatial distribution patterns of FTILs generated for 2021 are similar to those obtained using various other training sample sources,with a primary concentration observed along the central region traversed by the *** results highlight the slope as the most crucial feature in the fusion images,accounting for 93%of FTILs occurring on gentle slopes ranging from 0°to 14°.This study provides a theoretical framework and technological reference for the identification,monitoring,prevention and control of FTILs in *** developments hold the potential to benefit the management of grassland ecosystem,reduce economic losses,and promote grassland sustainability.

关键词： Permafrost degradation Random forest Thaw slump Spatial distribution Tibetan Plateau

Effect of quenching cooling rate on residual stress and microstructure evolution of 6061 aluminum alloy

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Journal of Central South University 2024年第7期31卷 2167-2180页

作者： HUANG Ke YI You-ping HUANG Shi-quan he hai-lin LIU Jie HUA Hong-en TANG Yun-jian Research Institute of Light Alloy Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Changsha 410083China School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China

In this study,the cooling rate was manipulated by quenching with water of different temperatures(30,60 and 100℃).Surface and internal residual stresses in the quenched 6061 aluminum alloy samples were measured using hole-drilling and crack compliance methods,***,the processability of the quenched samples was evaluated at cryogenic *** mechanical properties of the as-aged samples were assessed,and microstructure evolution was *** surface residual stresses of samples W30℃,W60℃and W100℃is−178.7,−161.7 and−117.2 MPa,respectively along x-direction,respectively;and−191.2,−172.1 and−126.2 MPa,respectively along *** sample quenched in boiling water displaying the lowest residual stress(~34%and~60%reduction in the surface and core).The generation and distribution of quenching residual stress could be attributed to the lattice distortion *** plasticity was also exhibited in the samples with relatively low quenching cooling rates at cryogenic *** strengthes of the as-aged samples are 291.2 to 270.1 MPa as the quenching water temperature increase from 30℃to 100℃.Fine and homogeneous β"phases were observed in the as-aged sample quenched with boiling water due to the clusters and Guinier-Preston zones(GP zones)premature precipitated during quenching process.

关键词： 6061 aluminum alloy residual stress cooling rate cryogenic cooling mechanical properties microstructure evolution

Endoscopic treatment of extreme esophageal stenosis complicated with esophagotracheal fistula: A case report

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 239-247页

作者： Jia-heng Fang Wei-Min Li Cheng-hai he Jian-Liang Wu Yun Guo Zhi-Chao Lai Guo-Dong Li Department of Gastroenterology Hangzhou Normal University Affiliated HospitalHangzhou 310000Zhejiang ProvinceChina

BACKGROUND At present,there is no unified and effective treatment for extreme corrosive esophageal stenosis(CES)with esophagotracheal fistula(ETF).This case had extreme and severe esophageal stenosis(ES)and ETF after ingesting an enzyme-based chemical detergent,resulting in a serious pulmonary infection and severe *** gastrointestinal imaging showed that he had an ETF,and endoscopy showed that he had extreme and severe esophageal *** case was complex and difficult to *** to the domestic and foreign lite-rature,there is no universal treatment that is *** SUMMARY A patient came to our hospital with extreme ES,an ETF,and severe malnutrition complicated with pulmonary tuberculosis 1 mo after the consumption of an enzy-me-based *** ES was serious,and the endoscope was unable to pass through the *** treated him by endoscopic incision method(EIM),esophageal stent placement(ESP),and endoscopic balloon dilation(EBD)by using the bronchoscope and *** treatment not only closed the ETF,but also expanded the esophagus,with minimal trauma,greatly reducing the pain of the *** to the literature,there are no similar reported *** We report,for the first time,a patient with extreme CES complicated with ETF,where the endoscope could not be passed through his esophagus but he could be examined by bronchoscopy and treated by EIM,ESP,and EBD.

关键词： Extreme corrosive esophageal stenosis Esophagotracheal fistula Endoscopic incision method Esophageal stent placement Endoscopic balloon dilation Case report

Hydrogen-rich water alleviates constipation by attenuating oxidative stress through the sirtuin1/nuclear factor-erythroid-2-related factor 2/heme oxygenase-1 signaling pathway

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World Journal of Gastroenterology 2024年第20期30卷 2709-2725页

作者： Kai-Di Chen Kui-Ling Wang Chen Chen Yi-Jia Zhu Wen-Wen Tang Yu-Ji Wang Ze-Peng Chen Lin-hai he Yu-Gen Chen Wei Zhang Jiangsu Province Hospital of Chinese Medicine The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina The No.1 Clinical Medical College Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Jiangsu Collaborative Innovation Center of Chinese Medicine in Prevention and Treatment of Tumor The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Constipation,a highly prevalent functional gastrointestinal disorder,induces a significant burden on the quality of patients'life and is associated with substantial healthcare ***,identifying efficient therapeutic modalities for constipation is of paramount *** stress is a pivotal contributor to colonic dysmotility and is the underlying pathology responsible for constipation ***,we postulate that hydrogen therapy,an emerging and promising intervention,can serve as a safe and efficacious treatment for *** To determine whether hydrogen-rich water(HRW)alleviates constipation and its potential *** Constipation models were established by orally loperamide to Sprague-Dawley *** freely consumed HRW,and were recorded their 24 h total stool weight,fecal water content,and charcoal propulsion *** samples were subjected to 16S rDNA gene *** non-targeted metabolomic analysis,malondialdehyde,and superoxide dismutase levels were *** tissues were stained with hematoxylin and eosin,Alcian blue-periodic acid-Schiff,reactive oxygen species(ROS)immunofluorescence,and immunohistochemistry for cell growth factor receptor kit(c-kit),PGP 9.5,sirtuin1(SIRT1),nuclear factor-erythroid-2-related factor 2(Nrf2),and heme oxygenase-1(HO-1).Quantitative real-time PCR and western blot analysis were conducted to determine the expression level of SIRT1,Nrf2 and HO-1.A rescue experiment was conducted by intraperitoneally injecting the SIRT1 inhibitor,EX527,into constipated ***460 cells were induced with H2O2 and treated with the metabolites to evaluate ROS and SIRT1 *** HRW alleviated constipation symptoms by improving the total amount of stool over 24 h,fecal water content,charcoal propulsion rate,thickness of the intestinal mucus layer,c-kit expression,and the number of intestinal *** modulated intestinal microbiota imbalance and abnormaliti

关键词： Hydrogen-rich water Constipation Sirtuin1 Oxidative stress Gut microbiota Serum metabolites