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new trends in diagnosis and management of gallbladder carcinoma

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 13-29页

作者： Efstathios T Pavlidis ioannis n Galanis Theodoros E Pavlidis ^(nd)Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Gallbladder(GB)carcinoma,although relatively rare,is the most common biliary tree cholangiocarcinoma with aggressiveness and poor *** is closely associated with cholelithiasis and long-standing large(>3 cm)gallstones in up to 90%of *** other main predisposing factors for GB carcinoma include molecular factors such as mutated genes,GB wall calcification(porcelain)or mainly mucosal microcalcifications,and GB polyps≥1 cm in *** is made by ultrasound,computed tomography(CT),and,more precisely,magnetic resonance imaging(MRi).Preoperative staging is of great importance in decisionmaking regarding therapeutic *** staging is based on MRi findings,the leading technique for liver metastasis imaging,enhanced three-phase CT angiography,or magnetic resonance angiography for major vessel *** is also necessary to use positron emission tomography(PET)-CT or ^(18)f-fDG PET-MRi to more accurately detect metastases and any other occult deposits with active metabolic *** laparoscopy may detect dissemination not otherwise found in 20%-28.6%of *** treatment is needed,including surgical resection,targeted therapy by biological agents according to molecular testing gene mapping,chemotherapy,radiation therapy,and *** is of great importance to understand the updated guidelines and current treatment *** extent of surgical intervention depends on the disease stage,ranging from simple cholecystectomy(T1a)to extended resections and including extended cholecystectomy(T1b),with wide lymph node resection in every case or iV-V segmentectomy(T2),hepatic trisegmentectomy or major hepatectomy accompanied by hepaticojejunostomy Roux-y,and adjacent organ resection if necessary(T3).Laparoscopic or robotic surgery shows fewer postoperative complications and equivalent oncological outcomes when compared to open surgery,but much attention must be paid to avoiding *** addition to surgery.novel targe

关键词： Biliary tract neoplasms Extrahepatic cholangiocarcinoma Gallbladder carcinoma Gallbladder diseases Biliary tree diseases Gastrointestinal malignancies

Mycorrhizal f.ngi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： y.ngy.ng JiA Marcel G.A.VAn DER HEiJDEn Alain y.VALzAnO-HELD Markus JOCHER florian WALDER Postdoctoral Mobile Station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China Research Group Plant-Soil interactions AgroscopeZürich 8046Switzerland Research Group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland Research Group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

nitrogen(n)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced n enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial n *** mycorrhizal f.ngi(AMf)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMf involvement in n cycling under global change is still ***,we simulated n enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMf and continuously monitored different n pathways over nine *** found that high n enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AMf,based on aboveground *** presence of AMf always maintained plant n:phosphorus(P)ratios between 14 and 16,no matter how the soil n availability *** in plant n:P ratios due to the increased plant n and P uptake might thus be a primary pathway of AMf altering plant community ***,we constructed a comprehensive picture of AMf’s role in n cycling,highlighting that AMf reduced n losses primarily by mitigating n leaching,while n_(2)O emissions played a marginal *** mycorrhizal f.ngi reduced n_(2)O emissions directly through the promotion of n_(2)O-consuming *** underly.ng mechanism for reducing n leaching is mainly the AMf-mediated improved nutrient uptake and AMf-associated microbial *** results indicate that synergies between AMf and other soil microorganisms cannot be ignored in n cycling and that the integral role of AMf in n cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： n cycling n enrichment n uptake n:P ratio plant community structure symbiotic soil f.ngi

Opportunities and challenges of biodegradable zn-based alloys

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Journal of Materials Science & Technology 2020年第11期42卷 136-138页

作者： H.f.Li z.z.Shi L.n.Wang Beijing Advanced innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China

following the footsteps of biodegradable Mg-based and fe-based alloys,biodegradable zn-based alloy is a newcomer and rising star in the family of biodegradable metals and *** combined superior mechanical properties,appropriate degradation rates,excellent biocompatibility of biodegradable zn-based alloys have brought worldwide research interest on the design,development and clinical translation of zn-based *** present perspective has summarized opportunities and challenges in the development of biodegradable zn-based alloys.

关键词： Biodegradable zn-based alloys Clinical applications Mechanical properties Degradation behavior Biocompatibility Corrosion fatigue Bio-tribocorrosion

Ray tracing particle image velocimetry-Challenges in the application to a packed bed

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Particuology 2024年第1期84卷 194-208页

作者： Christin Velten Mirko Ebert Christian Lessig Katharina zahringer Lehrstuhl für Strömungsmechanik und Strömungstechnik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany institut für Simulation und Graphik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany

Ray tracing Particle image Velocimetry(RT-PiV)is an optical technique for high resolution velocity measurements in challenging optical systems,such as transparent packed beds,that uses ray tracing to correct for distortions introduced by transparent geometries in the light *** ray tracing based correction is a post processing step applied to the raw PiV particle images before classical PiV *** this study,RT-PiV is performed in the top layer of a body centred cubic(bcc)sphere packing with gaseous flow,where optical access is obtained by the use of transparent n-BK7 glass balls with a diameter of d=40 ***-PiV introduces new experimental and numerical challenges,for example a limited field of view,illumination difficulties,a very large required depth of field and high sensitivity to geometric parameters used in the ray tracing *** challenges and their implications are the main scope and discussed in the present ***,the validation of the ray tracing reconstruction step is presented and examples for the obtained corrected vector fields in a packed bed are *** results show the strength of the method in reconstructing velocity fields behind transparent spheres that would not have been accessible by optical measurement techniques without the ray tracing correction.

关键词： Ray tracing particle image velocimetry(RT-PiV) Transparent spherical particles Packed bed Distortion correction Gas flow

PREPARATiOn AnD AnALySiS Of ni-P-zn ELECTROLESS DEPOSiTiOn fROM ALKALi BATH

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 204-208页

作者： y.S.Huang f.z.Cui DepartmentofMaterialsScience＆Engineering TsinghuaUniversityBeijing100084China／／InstituteofBiomechanicsSouthChinaUniversityofTechnologyGuangzhou510641China DepartmentofMaterialsScience＆Engineering TsinghuaUniversityBeijing100084China

Electroless ni-P-zn alloys deposited from alkali bath were investigated in this paper. The deposition bath contained nickel sulfate, zinc chloride and hypophosp hate. The process parameters, such as temperature, pH and zinc salt concentratio n were presented and discussed. The microstructure of the coatings was studied b y XRD and SEM. The cathode glowing discharge characters of ni-P-zn depositions w ere studied with luminous neon lamps. Electrodes deposited by electroless ni-P a lloys were apt to sputter during luminous working hours. Electroless ni-P-zn dep ositions improved the discharge characters of the electrodes. With the concentra tion of zinc in the deposition rising to 4wt%, electrode sputter was largely res trained. The thickness of the deposition also influenced the discharge character s of the electrode. To avoid electrode sputter, the concentration of zinc has to rise with the thickness of the depositions.

关键词： electroless ni-P-zn alloy electrode sputter cathode glowing Discharge

nUMERiCAL STUDy On CREEP DAMAGE Of COMPOSiTES AT HiGH TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 493-497页

作者： y.P.Jiang z.f.yue School of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an710072 ChinaSchool of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an710072 China

A unit cell model is applied to study the creep damage behavior after fiber fractures in the fiber-reinforced composites at high temperature. The user subroutine CREEP has been programmed for ABAQUS. The fiber breakage results in a new crack. The results show that the stress concentration factor resulted from the fiber breakage increases with the creep time. The creep damage takes place near the crack, and then grows in the matrix along a certain angle, up to the total failure. The influences of the ratio of modulus of the fiber to the matrix (Ef/Em) on the creep deformation, damage and stress distributions have been studied. With the increasing Ef/Em, the damage in the matrix increases. Analysis on the different ductility of matrix shows that the creep damage of low ductile matrix composites is higher than high ductile matrix composites.

关键词： composites creep damage unit cell finite element method

(E)-1-[4-(2-hydroxy-5-methoxybenzylideneamino)-phenyl]ethanone and (E)-1-[4-(2-hydroxy-4-methoxybenzylideneamino) phenyl]ethanone:X-ray and DfT-calculated structures

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Chinese Journal of Structural Chemistry 2011年第1期30卷 111-119页

作者： SAHn Onur ByKGngR Orhan ALBAyRAK igdem ODABASOGLU Mustafa Department of Physics Faculty of Arts and SciencesOndokuz Mayls University Department of Science Education Sinop University Chemistry Programme Pamukkale University 20159 Denizli

The isomeric structures of（E）-1-[4-（2-hydroxy-5-methoxybenzylideneamino）-phenyl] ethanone（i） and（E）-1-[4-（2-hydroxy-4-methoxybenzylideneamino） phenyl]ethanone（Ⅱ） ,both C16H15nO3,have been determined using X-ray diffraction techniques and characterized by iR,and their molecular structures have also been optimized at the B3LyP/6-31G（d,p） level using density functional theory（DfT） . The energetic behaviors of the title compounds in solvent media have been examined using B3LyP method with the 6-31G（d,p） basis set by apply.ng the polarizable continuum model（PCM） . The total energies of the title compounds decrease with the increasing polarity of the solvent. in addition,DfT calculations of the title compounds＇ molecular electrostatic potentials（MEP） were performed at the B3LyP/6-31G（d,p） level of theory. X-ray study shows that the title compounds both have strong intramolecular O-H…n hydrogen bonds. The molecules of Ⅰ are linked into a one-dimensional framework structure by C-H…π interactions,while in Ⅱ,intermolecular π···π interactions result in the formation of infinite chains running along the [010].

关键词： crystal structure Schiff base DfT molecular electrostatic potential

青藏高原及其周边第四纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1379-1410页

作者：王永郑绵平凌媛向树元邵兆刚张克信柯学林晓韩芳韩建恩中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037 中国地质大学(武汉)地球科学学院武汉430074 中国地质科学院北京100037 中国地质大学(武汉)地质调查研究院武汉430074 东华理工大学地球科学学院南昌330013 中国地质科学院地质力学研究所北京100081

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉... 详细信息

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉积特征及地貌、流域水系的差异,将青藏高原及其周边第四纪地层划分为5个地层区:塔里木区、黄土高原区、青藏高原区、云贵高原区及印度-恒河区.并将青藏高原地层区划分为西昆仑-喀喇昆仑分区、阿尔金-祁连山分区、柴达木-河湟分区、东昆仑-巴颜喀拉分区、羌塘分区、藏东-滇西-川西分区及冈底斯-喜马拉雅分区等7个地层分区.简要描述了青藏高原7个地层分区的岩石地层单元,根据各个地层分区的岩石地层序列及其沉积特征、地层接触关系、形成时代与生物群演化,将青藏高原第四纪的构造古地理演化划分为4个阶段:(1) 2.6~1.8/1.5Ma,上新世以来继承性差异隆升阶段,区域沉积差异显著,地层分布较局限,沿山前地带普遍发育冲洪积砂砾岩,山间低洼地河湖相沉积发育;(2) 1.8/1.5~1.2/0.8Ma,高原整体夷平阶段,高原及周边不整合面广泛分布,大型河流形成,山间盆地及高原腹地发育湖泊沉积物;(3) 1.2/0.8~0.128Ma,高原大范围持续隆升,地形差异显著,山体切割加剧,约0.8Ma高原进入冰冻圈,山地冰川发育,高寒干旱环境逐步形成;(4)0.128Ma~,山体上升与侵蚀切割加剧,山间盆地湖泊广泛分布,区域沉积特征差异较大,沉积类型向多样化发展,现代高原地貌格局基本形成.

关键词：青藏高原第四纪地层对比生物群古地理

Microstructural Evolution and Mechanical Properties of Laminated CuAl Composites Processed by Accumulative Roll-Bonding and Annealing

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 925-931页

作者： H.R.Lin y.z.Tian S.J.Sun z.f.zhang Shi-changxu innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Research Center for Metallic Wires Northeastern UniversityShenyang 110819China

nano structured Cu-/Al-laminated composites were processed by accumulative roll-bonding(ARB)technique for four *** evolutions inside the Cu and Al layers and the interfacial reactions were revealed after annealing at different *** and recrystallization occurred in the Cu and Al layers at low annealing temperatures,and three kinds of intermetallic compounds formed near the *** mechanical properties of these composites after annealing were investigated by tensile tests,and the variation of strength-ductility synergy was comprehensively discussed by considering the roles of constituent and the intermetallic compounds.

关键词： CuAl composites Accumulative roll-bonding(ARB) Annealing intermetallic compounds Ductility