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STUDIES On DERIVATIVES OF CLERODAnE DITERPEnOIDSFROM AJUGA DECUMBEnS

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Chinese Chemical Letters 1996年第6期7卷 549-552页

作者： Chen, HM Xie, n min, ZD nAnKAI UnIV INST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA CHInA PHARMACEUT UnIV DEPT PHYTOCHEMNANJING 210009PEOPLES R CHINA

Some derivatives of neo-clerodane diterpenes ajugacumbin A and B isolated from Ajuga decumbens were prepared by various chemical transformations, and the results achieved in the biological assay as insect antifeedants...

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Universality of quenching-partitioning-tempering local equilibrium model

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Journal of Materials Science & Technology 2022年第29期124卷 116-120页

作者： J.Z.Zhang L.y.Zeng X.W.Zuo J.F.Wan y.H.Rong n.min J.Lu n.L.Chen Department of Mechanical Engineering City University of Hong KongGreater Bay Joint DivisionShenyang National Laboratory for Materials ScienceTat Chee AvenueKowloonHong KongChina Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Laboratory for Microstructures Shanghai UniversityShanghai 201900China CityU-Shenzhen Futian Research Institute Shenzhen 518045China

*** As typical 3rd generation advanced high strength steels(AHSSs),quenching and partitioning(Q&P)steel has attracted lots of attention for excellent performance in strength-ductility[1–5].With absorbing carbon partitioning as the core idea of Q&P process,quenching-partitioning-tempering(Q-P-T)process was proposed with emphasis on precipitation strengthening for better combination of strength and ductility[6–10].

关键词： tempering strength ductility

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

踝关节骨折术后踝穴冠状位角度波动与关节功能恢复的关系

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中国组织工程研究 2025年第9期29卷 1820-1826页

作者：刘琰王铠吴敏泰州市中医院骨科江苏省泰州市225300

背景:踝关节骨折术后的踝穴形态指标会出现相应变化,而其中踝穴冠状位角度变化与踝关节的功能恢复之间存在一定的关联,既往研究大多探讨患者术后踝穴高度恢复,故研究踝关节骨折术后踝穴冠状位角度的波动与关节功能恢复的相关性具有一定... 详细信息

背景:踝关节骨折术后的踝穴形态指标会出现相应变化,而其中踝穴冠状位角度变化与踝关节的功能恢复之间存在一定的关联,既往研究大多探讨患者术后踝穴高度恢复,故研究踝关节骨折术后踝穴冠状位角度的波动与关节功能恢复的相关性具有一定参考意义。目的:探讨踝关节骨折术后踝穴冠状位角度变化对关节功能恢复的影响。方法:纳入进行手术治疗的86例踝关节骨折患者为研究对象,根据末次随访美国骨科足踝外科协会踝-后足评分结果分为优良组(n=45)和可差组(n=41),比较两组患者的一般资料。根据踝关节的踝穴位及侧位X射线片对比术后患者患侧和健侧的踝穴形态指标:包括踝穴宽度和深度、冠状位角度及矢状位角度,以及上述指标患侧和健侧之间的差值,并进一步进行组内比较分析。构建联合模型,利用Cox回归分析评估冠状位角度波动与关节功能恢复情况的关系。利用最小绝对收缩选择算子回归法和多因素Logistic回归分析影响患者关节功能恢复的危险因素。按踝穴冠状位角度从低到高等分为5分位数组(Q1-Q5),比较5组患者的临床资料特征,并采用多因素Logistic回归分析踝穴冠状位角度变化与关节功能恢复不良风险的相关性,建立限制性立方样条Logistic回归模型分析其剂量-反应关系。建立回归方程y=1-1/(1+e^(-z))预测模型并进行验证。结果与结论:①患者患侧的踝穴宽度和深度、冠状位角度及矢状位角度均显著大于健侧(P均<0.05);且与优良组患者相比,可差组患者踝穴宽度差值、深度差值、冠状位角度差值及矢状位角度差值均更大(P<0.05);②联合模型显示无论冠状位角度是否在正常范围内,冠状位角度每纵向增加1˚,关节功能恢复不良的风险增加3%;③最小绝对收缩选择算子回归和多因素Logistics回归分析显示,调整潜在混杂因素后发现年龄过大、早期功能锻炼缺乏、无跟骨牵引、内固定物未取出、术后并发症、踝冠状位角度增大均为影响患者关节功能恢复的独立危险因素(P<0.05);④术后3个月内的冠状位角度与关节功能恢复效果不良风险存在独立相关性(OR=1.57,95%CI:1.38-1.76,P=0.002),且术后各时间段冠状位角度从低到高5分位数组趋势性检验差异有统计学意义(P趋势<0.001);⑤限制性立方样条模型分析显示,男性或女性的踝穴冠状位角度变化与关节功能恢复效果不良风险均不存在非线性关系;经Bootstrap自抽样,预测模型区分度、准确度较好;⑥提示踝关节骨折术后踝穴冠状位角度减小对关节功能恢复起到明显的促进作用,因此在踝关节骨折术后重点检测踝穴冠状位角度有助于了解患者关节功能恢复情况。

关键词：踝关节骨折踝穴冠状位角度关节功能 Logistic回归分析

An atomistic approach for the structural and electronic properties of twisted bilayer graphene-boron nitride heterostructures

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npj Computational Materials 2022年第1期8卷 687-696页

作者： min Long Pierre A.Pantaleón Zhen Zhan Francisco Guinea JoseÁngel Silva-Guillén Shengjun yuan Key Laboratory of Artificial Micro-and nano-structures of ministry of Education and School of Physics and Technology Wuhan UniversityWuhan430072China Imdea nanoscience C/Faraday 928015MadridSpain Donostia International Physics Center Paseo Manuel de Lardizábal 420018San SebastiánSpain Ikerbasque Basque Foundation for Science48009BilbaoSpain Wuhan Institute of Quantum Technology Wuhan430206China

Twisted bilayer graphene(TBG)has taken the spotlight in the condensed matter community since the discovery of correlated *** this work,we study heterostructures of TBG and hexagonal boron nitride(hBn)using an atomistic tight-binding model together with semi-classical molecular dynamics to consider relaxation *** hBn substrate has significant effects on the band structure of TBG even in the case where TBG and hBn are not ***,the substrate induces a large mass gap and strong pseudo-magnetic fields that break the layer ***,such degeneracy can be recovered with a second hBn ***,we develop a continuum model that describes the tight-binding band *** results show that a real-space tight-binding model in combination with semi-classical molecular dynamics is a powerful tool to study the electronic properties of moiréheterostructures,and to explain experimental results in which the effect of the substrate plays an important role.

关键词： boron electronic twisted

High-Speed Friction Stir Welding of T6-Treated B4Cp/6061Al Composite

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 67-74页

作者： y.Z.Li y.n.Zan Q.Z.Wang B.L.Xiao Z.y.Ma Key Laboratory of nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China Sheny.ng national Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China University of Science and Technology of China Shenyang 110016China

T6-treated 20 wt% B4 Cp/6061 Al sheets were joined under welding speeds of 400–1200 mm/min by friction stir welding(FSW) with a threaded cermet pin. The macro-defect-free FSW joints could be achieved at high welding speeds up to 1200 mm/min, but larger plunge depth was required at the welding speeds of 800 and 1200 mm/min to eliminate the tunnel defect. In the nugget zone(nZ) of the joints, the B4 C particles were broken up and uniformly redistributed. The nZ exhibited lower hardness than the base metal(BM), and the hardness value almost did not change with increasing welding speed, attributable to the dissolution of precipitates. Compared with the BM, the joints showed lower tensile strength. As the welding speed increased from 400 to 800 mm/min, the joint efficiencies were nearly the same and up to ~ 73%. When the welding speed increased up to 1200 mm/min, the tensile strength significantly decreased, due to the occurrence of kissing bond defect at the bottom of the nZ. With increasing welding speed, the fracture location of the joints transferred gradually from the heat-affected zone to the nZ due to the kissing bond defects.

关键词： Metal-matrix composites Microstructures Mechanical properties Friction stir welding High-speed welding

Acid suppressive drugs and gastric cancer: A meta-analysis of observational studies

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World Journal of Gastroenterology 2013年第16期19卷 2560-2568页

作者： Jeong Soo Ahn Chun-Sick Eom Christie y Jeon Sang min Park Department of Family Medicine Seoul National University Hospital Seoul National University College of Medicine Department of Family Medicine Hallym University Chuncheon Sacred Heart Hospital Center for Cancer Prevention and Control Research UCLA Fielding School of Public Health

AIM: To evaluate the association between acid suppressive drug use and the development of gastric cancer. METHODS: A systematic search of relevant studies that were published through June 2012 was conducted using the MEDLInE (PubMed), EMBASE, and Cochrane Library databases. The search included observational studies on the use of histamine 2-receptor antagonists (H 2 RAs) or proton pump inhibitors and the associated risk of gastric cancer, which was measured using the adjusted odds ratio (OR) or the relative risk and 95%CI. An independent extraction was performed by two of the authors, and a consensus was reached. RESULTS: Of 4595 screened articles, 11 observational studies (n = 94558) with 5980 gastric cancer patients were included in the final analyses. When all the studies were pooled, acid suppressive drug use was associated with an increased risk of gastric cancer risk (adjusted OR = 1.42; 95%CI: 1.29-1.56, I2 = 48.9%, P = 0.034). The overall risk of gastric cancer increased among H 2 RA users (adjusted OR = 1.40; 95%CI: 1.24-1.59, I2 = 59.5%, P = 0.008) and PPI users (adjusted OR = 1.39; 95%CI: 1.19-1.64, I2 = 0.0%, P = 0.377). COnCLUSIOn: Acid suppressive drugs are associated with an increased risk of gastric cancer. Further studies are needed to test the effect of acid suppressive drugs on gastric cancer.

关键词： H2-receptor antagonists Proton pump inhibitors Gastric cancer Meta-analysis

Study on Force Mechanism for Therapeutic Effect of Pushing Manipulation with One-Finger Meditation Base on Similarity Analysis of Force and Waveform

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Chinese Journal of Integrative Medicine 2018年第7期24卷 531-536页

作者： FAnG Lei FAnG min GUO min-min School of Rehabilitation Science Shanghai University of Traditional Chinese Medicine Department of Tuina Yueyang Hospital of Integrated Traditional Chinese and Western Medicine Department of Mechanics and Engineer Science Fudan University

Objective： To reveal the force mechanism for therapeutic effect of pushing manipulation with one-finger meditation. Methods： A total of 15 participants were recruited in this study and assigned to an expert group, a skilled group and a novice group, with 5 participants in each group. Mechanical signals were collected from a biomechanical testing platform, and these data were further observed via similarity analysis and cluster analysis. Results： Comparing the force waveforms of manipulation revealed that the manipulation forces were similar between the expert group and the skilled group（P〉0.05）. The mean value of vertical force was 9.8 n, and 95% CI rang from 6.37 to 14.70 n, but there were significant differences compared with the novice group（P〈0.05）. The result of overall similarity coefficient cluster analysis showed that two kinds of manipulation forces curves were existed between the expert group and the skilled group. Conclusion： Pushing manipulation with one-finger meditation is a kind of light stimulation manipulation on the acupoint, and force characteristics of double waveforms continuously alternated during manual operation.

关键词： pushing manipulation with one-finger meditation Tuina biomechanics force characteristics waveform

Features of Rotating Stall Cell in a Diagonal Flow Fan (in Case of Mid-loading Rotor)

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Journal of Thermal Science 2006年第2期15卷 103-108页

作者： n.SHIOMI K. KAnEKO y. KInOUE T. SETOGUCHI Department of Mechanical Engineering Saga University Saga 840-8502 Japan

The structure and behavior of rotating stall cell were experimentally clarified in a diagonal flow fan. The specific-speed of the fan was 1140 （r/min, m^3/min, m）, and the total pressure-rise coefficient at design flow-rate was 0.345. The static pressure on outer casing wall and the total pressure at rotor inlet and outlet were measured using a high response pressure transducer. The measured data were processed by the use of DPLA technique, and the structure and behavior of rotating stall cell were obtained. As a result, the stall cell extent for circumferential and spanwise direction and the pressure distributions inside stall cell were clarified. The details of stall cell propagation were also shown.

关键词： diagonal flow fan rotating stall cell unsteady flow DPLA technique