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Dynamics of lattice disorder in perovskite materials, polarization nanoclusters and ferroelectric domain wall structures

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npj Computational Materials 2023年第1期9卷 1137-1149页

作者： jan očenášek Ján Minár Jorge Alcalá New Technologies Research Centre University of West Bohemia in Pilsen30614 PlzeňCzech Republic Department of Materials Science and Metallurgical engineering InSupETSEIBUniversitat Politècnica de Catalunya08028 BarcelonaSpain

The nexus between classic ferroelectricity and the structure of perovskite materials hinges on the concept of lattice *** the ordered perovskites display short-range displacements of the central cations around their equilibrium points,the lattice disorder dynamically unfolds to generate a myriad of distorted rhombohedral lattices characterized by the hopping of the central cations across*** is discovered that the lattice disorder correlates with the emergence of minimum configuration energypathways for the central cations,resulting in spatially modulated ultrafast polarization nanocluster arrangements that are stabilized by the electric charge defects in the *** high-resolution phonon dispersion analyses encompassing molecular dynamics(MD)and density functional theory(DFT)simulations,we provide unequivocal evidence linking the hopping of central cations to the development of diffuse soft phonon modes observed throughout the phase transitions of the *** massive MD simulations,we unveil the impact of lattice disorder on the structures of domain walls at finite-temperature vis-à-vis collective activation and deactivation of***,our simulations demonstrate the development of hierarchical morphotropic phase boundary(MPB)nanostructures under the combined influence of externally applied pressure and stress relaxation,characterized by sudden emergence of zig-zagged monoclinic arrangements that involve dualshifts of the central *** findings have implications for tailoring MPBs in thin-film structures and for the light-induced mobilization of *** are finally uncovered to the exploration of lattice disorder through gradual shear strain application.

关键词： perovskite lattice ferroelectric

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Nonsteroidal anti-inflammatory drugs before endoscopic ultrasound guided tissue acquisition to reduce the incidence of post procedural pancreatitis

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World Journal of Gastroenterology 2024年第8期30卷 811-816页

作者： Mike de Jong Foke van Delft Christine Roozen Erwin-jan van Geenen Tanya Bisseling Peter Siersema Marco Bruno Department of Gastroenterology and Hepatology Radboud University Medical CenterNijmegen 6525 GANetherlands Department of Gastroenterology and Hepatology Erasmus University Medical CenterRotterdam 3015 GDNetherlands

endoscopic ultrasound(EUS)with fine needle aspiration or fine needle biopsy is the gold standard for sampling tissue to diagnose pancreatic cancer and auto-immune pancreatitis or to analyze cyst *** most common reported adverse event of fine needle aspiration and/or fine needle biopsy is acute pancreatitis,which is likely induced by the same pathophysiological mechanisms as after en-doscopic retrograde cholangiopancreatography(ERCP).According to the current European Society of Gastrointestinal endoscopy guideline,nonsteroidal anti-inflammatory drugs are administered prior to ERCP as a scientifically proven treatment to reduce post-ERCP pancreatitis incidence rate.A single suppository of diclofenac or indomethacin prior to EUS guided tissue acquisition(TA)is harm-less in healthy *** it is associated with low costs and,most important,may prevent a dreadsome complication,we strongly recommend the adminis-tration of 100 mg diclofenac rectally prior to *** will explain this recom-mendation in more detail in this review as well as the risk and pathophysiology of post-EUS TA pancreatitis.

关键词： Pancreatitis endoscopic ultrasound Tissue acquisition Nonsteroidal antiinflammatory drugs Pancreatic cancer

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Littoral landforms of Lake Hulun and Lake Buir(China and Mongolia):Wind-driven hydro-sedimentary dynamics and resulting clastics distribution

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Journal of Palaeogeography 2024年第2期13卷 309-326页

作者： Li Wang Mathieu Schuster Shi-Wei Xin Florin Zainescu Xin-Yu Xue Joep Storms jan-Hendrik May Alexis Nutz Helena van der Vegt Guilherme Bozetti Zai-Xing Jiang School of energy Resources China University of Geosciences(Beijing)Beijing100083China Universite de Strasbourg CNRSENGEESInstitut Terre et Environnement de StrasbourgUMR 70635 Rue DescartesStrasbourgFrance Tamsag Mongolia(XIX)Ltd. PetroChinaDaqing 163000China CEREGE Aix-Marseille UniversitéCNESIRDCollege de FranceINRAAix en ProvenceFrance School of Marine Science Sun Yat-sen UniversityZhuhai 519083China Delft University of Technology Department of Geoscience and EngineeringDelfthe Netherlands School of Geography Earth and Atmospheric SciencesUniversity of Melbourne253 Elgin St.CarltonVIC 3053Australia Deltares Delfthe Netherlands SCMF Faculty of GeographyUniversity of Bucharest1 N.Balcescu Blv.BucharestRomania

Two rectangular-shaped lakes,Lake Hulun and Lake Buir,located at the boundary between China and Mongolia,only c.75 km apart and therefore experiencing similar wind fields,have been studied based on satellite images and field surveys in order to compare their geomorphological and sedimentological *** wind-driven hydrodynamics,which have a significant effect on the development of littoral landforms and on sediment distribution,have been discussed for the two similar lakes that experienced a prevailing wind perpendicular to their long axis.A conceptual model related to wind-driven water bodies and sediment distribution is ***-influenced to wave-dominated deltas,beaches,spits,and eolian dune deposits develop around these two lakes,with a strikingly similar distribution *** features locally inform the longshore drift and help reconstruct the water circulation induced by wind *** the NW prevailing wind regime,the spits developed on the SW coast with a NW—SE extension,which was influenced by the NW—SE longshore *** same influence was observed in the delta extension in the NE *** differences lie in the presence of fan deltas in the NW region of Lake Hulun,but not in Lake ***,the width of the beach and eolian deposits on the downwind coast of Lake Hulun is three times greater than that of Lake Buir which were caused by the differences in sediment supply and wind fetch between the two *** Hulun and Lake Buir provide two reliable examples to understand the relationship among the wind field,provenance,hydrodynamics,landforms,and asymmetrical distribution of clastics in elongated *** also represent relevant modern analogs,which may also be of guiding significance to wind-driven sand body prediction in lacustrine basins.

关键词： Wind-driven lakes Fetch Sedimentary facies Hydrodynamics Geomorphology Spits Shoreline Lake Hulun Lake Buir

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Cavitation and grain boundary sliding during creep of Mg-Y-Nd-Zn-Mn alloy

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中国有色金属学会会刊：英文版 2008年第A01期18卷 64-68页

作者： V.janíK F.HNILICA P.ZUNA V.oenEK I.STULíKoV Department of Materials engineering Faculty of Mechanical EngineeringCzech Technical University in PraguePragueCzech Republic Research Institute for Metals Panenské BrezanyCzech Republic Faculty of Mathematics and Physics Charles UniversityPragueCzech Republic

Creep of squeeze-cast Mg-3Y-2Nd-1Zn-1Mn alloy was investigated at the constant load in the stress range of 30-80 MPa. Tensile creep tests were performed at 300℃up to the final *** tests at 50 MPa were interrupted after reaching the steady state creep;and another set of creep tests was interrupted after the onset of ternary *** of cavitated dendritic boundaries was evaluated using optical *** of grain boundary sliding by observation of the offset of marker lines was carried out on the surface of the crept specimens after the test interruption by scanning electron microscopy and by confocal laser scanning *** results show that the dominant creep mechanism in this alloy is dislocation creep with minor contribution of the grain boundary *** failure took place by the nucleation,growth and coalescence of creep cavities on the boundaries predominantly oriented perpendicular to the applied *** amount of cavitated boundaries with time of creep exposure supports the mechanism of continuous cavity nucleation and growth.

关键词：镁合金锌合金锰合金高温测试

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416例异位妊娠患者行甲氨蝶呤单次注射的治疗结局及影响因素分析

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复旦学报（医学版） 2024年第3期51卷 378-384页

作者：林晓龙姜文清邹世恩复旦大学附属妇产科医院妇科上海200011

目的探讨甲氨蝶呤(methotrexate,MTX)单次注射治疗异位妊娠的结局及相关影响因素。方法回顾性分析2019年1月至2022年12月在复旦大学附属妇产科医院住院的416例异位妊娠患者,均行MTX单次注射,用药当天记为第1天,在用药第4天和第7天复查血... 详细信息

目的探讨甲氨蝶呤(methotrexate,MTX)单次注射治疗异位妊娠的结局及相关影响因素。方法回顾性分析2019年1月至2022年12月在复旦大学附属妇产科医院住院的416例异位妊娠患者,均行MTX单次注射,用药当天记为第1天,在用药第4天和第7天复查血β-人绒毛膜促性腺激素(β-human chorionic gonadotrophin,β-hCG)。与第4天相比,第7天血β-人绒毛膜促性腺激素下降15%,为初始治疗有效,继续随访直至β-hCG下降至正常水平,纳入成功组。收集两组患者基线信息和治疗结局,并分析与治疗结局相关的影响因素。结果失败组纳入70例,成功组纳入346例。失败组中用药前β-hCG上升人数比例显著高于成功组(55.2%vs.35.8%,P=0.007),用药前β-hCG下降人数比例显著低于成功组(43.1%vs.63.6%,P=0.007)。失败组单核细胞计数显著低于成功组[(0.43±0.13)×10^(9)/L vs.(0.47±0.17)×10^(9)/L,t=-2.001,P=0.047)]。两组用药前β-hCG、β-hCG变化速度、白蛋白、血肌酐、白细胞计数、中性粒细胞计数、血小板平均体积、中性粒细胞-淋巴细胞比值、血小板-淋巴细胞比值、淋巴细胞-单核细胞比值的差异均无统计学意义。Logistic回归分析表明治疗结局与用药前β-hCG变化方式和单核细胞计数有关,用药前β-hCG下降(oR=2.313,95%CI:1.222~4.379,P=0.010)和单核细胞计数≥0.6×10^(9)/L(oR=4.018,95%CI:1.207~13.378,P=0.023)对治疗结局有显著影响。结论用药前β-hCG下降和单核细胞计数≥0.6×10^(9)/L是MTX单次注射成功治疗异位妊娠的独立影响因素。

关键词：异位妊娠甲氨蝶呤(MTX) 单次注射单核细胞计数 β-人绒毛膜促性腺激素(β-hCG)

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2型糖尿病患者肺部感染TLR2/TLR4炎症信号通路及其危险因素

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中华医院感染学杂志 2024年第4期34卷 498-502页

作者：程文刘恩楠王品蔡科娟向松四川省人民医院内分泌科四川成都610000 四川省人民医院门诊部四川成都610000

目的探究2型糖尿病患者肺部感染Toll样受体(TLR)2/TLR4炎症信号通路及其危险因素.方法回顾性分析2021年1月—2023年1月四川省人民医院收治的168例2型糖尿病患者的临床资料,根据2型糖尿病患者肺部感染情况分为感染组(n=33)和非感染组(n=1... 详细信息

目的探究2型糖尿病患者肺部感染Toll样受体(TLR)2/TLR4炎症信号通路及其危险因素.方法回顾性分析2021年1月—2023年1月四川省人民医院收治的168例2型糖尿病患者的临床资料,根据2型糖尿病患者肺部感染情况分为感染组(n=33)和非感染组(n=135);统计2型糖尿病患者肺部感染病原菌,归纳2型糖尿病患者肺部感染的危险因素,比较两组外周血单个核细胞(PBMC)中TLR2、TLR4表达情况.结果33例2型糖尿病肺部感染患者共培养分离病原菌48株,其中革兰阴性菌29株占60.42%,革兰阳性菌14株占29.17%,真菌5株占10.42%,以大肠埃希菌、肺炎克雷伯菌为主;2型糖尿病病程、肺部并发症、住院时间是2型糖尿病患者肺部感染的危险因素(P<0.05);非感染组PBMC中TLR2 mRNA、TLR4 mRNA水平均低于感染组(P<0.001).结论2型糖尿病患者肺部感染病原菌以革兰阴性菌为主;2型糖尿病病程、肺部并发症、住院时间是2型糖尿病患者肺部感染的危险因素;2型糖尿病患者肺部感染PBMC中TLR2、TLR4呈高表达,临床可据此予以早期针对性防治而降低2型糖尿病患者肺部感染的发生风险.

关键词： 2型糖尿病肺部感染 Toll样受体2/Toll样受体4炎症信号通路病原菌危险因素

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Water yield and biomass production for on a eucalypt-dominated Mediterranean catchment under different climate scenarios

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林业研究:英文版 2023年第5期34卷 1263-1278页

作者： Joao Rocha Ana Quintela Dalila Serpa jan Jacob Keizer Sérgio Fabres RAIZ-Forest and Paper Research Institute Quinta de S.FranciscoRua JoséEstevao(EN 230-1)3800–783 EixoAveiroPortugal Department of environment and Planning Centre of Environmental and Marine Studies(CESAM)University of AveiroCampus Universitário de Santiago3810–193 AveiroPortugal

Worldwide,forests are vital in the regulation of the water cycle regulation and in water balance *** of ecohydrological responses of production forests is essential to support management strategies,especially where water is already *** climatological patterns are expected to impact thermopluviometric regimes,water cycle components,hydrological responses,and plant physiology,evapotranspiration rates,crop productivity and land management *** work(1)assessed the impacts of different predicted climate conditions on water yield;(2)inferred the impacts of climate change on biomass production on eucalypt-to-eucalypt succes *** this end,the widely accepted Soil and Water Assessment Tool(SWAT)was run with the RCA,HIRHAM5 and RACMo climate models for two emission scenarios(RCP 4.5 and8.5).Three 12-year periods were considered to simulate tree growth under coppice *** results revealed an overall reduction in streamflow and water yield in the catchment in line with the projected reduction in total annual ***,HIRHAM5 and RACMo models forecast a slight shift in seasonal streamflow of up to 2 months(for2024-2048)in line with the projected increase in precipitation from May to *** biomass production,the extreme climate model(RCA)and severe emis sion scenario(RCP 8.5)predicted a decrease up to 46%.However,in the less extreme and more-correlated(with actual catchment climate conditions)climate models(RACMo and HIRHAM5)and in the less extreme emission scenario(RCP 4.5),biomass production increased(up to 20%),and the growth cycle was slightly *** was proven to be a valuable tool to assess climate change impacts on a eucalypt-dominated catchment and is a suitable decision-support tool for forest managers.

关键词： Climate scenarios Forested catchments Forest ecohydrological modelling Eucalypt biomass production SWAT model

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A Comparison of Experimental and Numerical Studies Performed on a Low-Pressure Turbine Blade Cascade at High-Speed Conditions, Low Reynolds Numbers and Various Turbulence Intensities

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Journal of Thermal Science 2013年第5期22卷 413-423页

作者： jan Michalek Petr Straka VZLU - Aerospace Research and Test Establishment Beranovych 130 19500 PragueCzech Republic

This paper focuses on a comparison of experimental and numerical investigations performed on a low-pressure mid-loaded turbine blade at operating conditions comprised of a wide range of Math numbers （from 0.5 - 1.1）, Reynolds numbers （from 0.4e＋5 - 3.0e＋5）, flow incidence （-15 - 15 degrees） and three levels of free-stream tur- bulence intensities （2, 5 and 10%）. The experimental part of the work was performed in a high-speed linear cas- cade wind tunnel. The increased levels of turbulence were achieved by a passive grid placed at the cascade inlet. A two-dimensional flow field at the center of the blade was traversed pitch-wise upstream and downstream the cascade by means of a five-bole probe and a needle pressure probe, respectively. The blade loading was measured using the surface pressure taps evenly deployed at the blade mid-span along the suction and the pressure side. The inlet turbulence was investigated using the constant temperature anemometer technique with a dual sensor probe. Experimentally evaluated values of turbulent kinetic energy and its dissipation rate were then used as inputs for the numerical simulations. An in-house code based on a system of the Favre-averaged Navier-Stokes equation closed by a two-equation k-co turbulence model was adopted for the predictions. The code utilizes an algebraic model of bypass transition valid both for attached as for separated flows taking in account the effect of free-stream turbulence and pressure gradient. The resulting comparison was carried out in terms of the kinetic en- ergy loss coefficient, distributions of downstream wakes and blade velocity. Additionally a flow visualization was performed by means of the Schlieren technique in order to provide a further understanding of the studied phe- nomena. A few selected cases with a particular interest in the attached and separated flow transition are compared and discussed.

关键词： low pressure turbine high-speed flow low Reynolds number flow separation transition RANS

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Solid-pseudopapillary tumor of the pancreas: Clinical experience and literature review

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World Journal of Gastroenterology 2005年第9期11卷 1403-1409页

作者： Hsueh-Lien Huang Shou-Chuan Shih Wen-Hsiung Chang Tsang-en Wang Ming-Jen Chen Yu-jan Chan Division of Gastroenterology

AIM: To evaluate the clinical presentations of solidpseudopapillary tumor of the pancreas (SPT) and examine the diagnosis, treatment, low grade malignant potential of this rare ***: We retrospectively reviewed a series of seven patients with SPT managed in our hospital between July 1990 and october 2003. Six females and one male with mean age of 31 years (range 13 to 50 years) were diagnosed with SPT at our ***: Clinical presentation included a palpable abdominal mass in two patients and vague abdominal discomfort in another two. Two patients were asymptomatic;their tumors were found incidentally on abdominal sonographic examination for other reasons. The final patient was admitted with hemoperitoneum secondary to tumor rupture. The mean diameter of the tumors in the seven patients was 10.5 cm (range 5 to 20 cm). The lesions were located in the body and tail in five cases and in the head of the pancreas in two. Surgical procedures included distal pancreatectomy (3), distal pancreatectomy with splenectomy (2), pancreaticoduodenectomy (1) and a pylorus-preserving Whipple procedure (1). There were gross adhesions or histological evidence of infiltration to the adjacent pancreas and/or splenic capsule in four cases. None of the patients received adjuvant *** mean follow up was 7 years (range 0.5 to 14 years).one patient developed multiple liver metastases after 14 years of follow ***: SPT is a rare tumor that behaves less aggressively than other pancreatic tumor. However, in cases with local invasion, long-term follow up is advisable.

关键词： Solid-pseudopapillary tumor of the pancreas Distal pancreatectomy Pancreaticoduodenectomy

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Genetic enhancement of Indigenous Cowpea with Gamma-Ray Induced Trait Variation

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American Journal of Plant Sciences 2024年第8期15卷 651-676页

作者： Mathurin Tiergnin Dabiré Minimassom Philippe Nikiéma Djibril Yonli Safiatou Sanna Wossoguim Josué Gouba Siébou Palé Hamidou Traoré Joseph T. B. Batieno Varra Prasad Zacharia Stewart jan B. Middendorf Abhishek Rathore Anupama J. Hingane Unit de Formation et de Recherches en Sciences et Technologies Dpartement des Sciences de la Vie et de la Terre Universit Norbert ZONGO Koudougou Burkina Faso Institut de lenvironnement et de Recherches Agricoles (INERA) Ouagadougou Burkina Faso Department of Agronomy Kansas State University Manhattan USA Center for Agriculture-Led Growth Bureau for Resilience and Food Security United States Agency for International Development United States Agency for International Development Washington DC USA International Maize and Wheat Improvement Center (CIMMYT) ICRISAT Campus Patancheru India Joint FAo/IAEA Division of Nuclear Techniques in Food and Agriculture Department of Nuclear Sciences and Applications Plant Breeding and Genetics Laboratory International Atomic Energy Agency (IAEA) Seibersdorf Vienna Austria

Production of cowpea (Vigna unguiculata (L.) Walp.), a staple legume crop in Sub-Saharan Africa, faces challenges due to biotic and abiotic constraints. Induced mutagenesis was deployed to create genetic variation in two cowpea varieties (KVX396-4-5-2D and Moussa local). The radio-sensitivity tests led to determe the lethal dose 50 (LD50) corresponding to 230 Gy and 220 Gy for KVX396-4-5-2D and Moussa local varieties, respectively. Dried seeds (M0) of each variety were gamma-ray irradiated with LD50 − 50, LD50 and LD50 + 50. M1 seeds were advanced to generate M2, M3 and M4 mutants using the single-seed-descent method. M4 mutant lines were evaluated in rain-fed conditions using a randomized complete block design to assess phenotypic differences. Data on seven qualitative and eleven quantitative traits were collected. The results indicated that the mutation induced variability in three qualitative traits: in KVX 396-4-5-2D mutant lines, with flower and seed color frequencies at 2.61% and 0.56% respectively, and pod dehiscence at a frequency of 0.24%. While in Moussa local mutants, a pod color changed at a frequency of 17%. ANoVA results revealed significant differences between mutants of both varieties for all quantitative traits, including photosynthetic parameters. Positive correlations were observed between leaf diameter and 100-seed weight, and between branch number and 100-seed weight. Hierarchical clustering revealed three clusters among KVX 396-4-5-2D mutants and six clusters among Moussa local mutants. Early maturity and high foliage were induced traits in Cluster 3 of KVX 396-4-5-2D mutants while high hundred-seed weight was induced in Cluster 6 of Moussa local mutants.

关键词： Cowpea Mutagenesis Gamma Rays Radio-Sensitivity Phenotyping

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