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Advances in Manufacturing 2020年第1期8卷 119-132页

作者： Wen-hua Ye Yun-xia Guo Heng-Fei zhou Rui-Jun Liang Wei-Fang Chen College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China Department of Mechanical Engineering Henan Institute of TechnologyXinxiang 453003HenanPeople's Republic of China

This paper describes a novel modeling method for determining the thermal deformation coefficient of the moving shaft of a machine ***,the relation between the thermal deformation coefficient and the thermal expansion coefficient is expounded,revealing that the coefficient of thermal deformation is an important factor affecting the precision of moving shaft feed ***,thermal errors and current boundary and machining conditions are measured using sensors to obtain the first set of parameters for a thermal prediction *** dynamic characteristics of the positioning and straightness thermal errors of the moving axis of a machine tool are analyzed under different feed speeds and mounting modes of the moving shaft and ***,the theoretical model is derived from experimental data,and the axial and radial thermal deformation coefficients at different time and positions are *** expressions for the axial and radial thermal deformation of the moving shaft are modified according to theoretical considerations,and the thermal positioning and straightness error models are established and experimentally *** modeling method can be easily extended to other machine tools to determine thermal deformation coefficients that are robust and self-correcting.

关键词： Moving shaft Ball screw Thermal expansion Thermal deformation coefficient Error modeling

Zinc finger protein rotund deficiency affects development of the thoracic leg in Bombyx mori

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Insect Science 2017年第3期24卷 385-396页

作者： Chun-Yan zhou Xing-Fu Zha hua-Wei Liu Qing-You xia State Key Laboratory of Silkworm Genome Biology College of Biotechnology Southwest University Chongqing China

The insect limb develops from the imaginal disc or larval leg during metamor- phosis. The molecular mechanisms involved in the development from the larval to the adult leg are poorly understood. Herein, we cloned the full length of a zinc finger gene rotund from Bombyx mori （Bmrn）, which contained a 1419 bp open reading frame, and encoded a 473 amino acid protein. Reverse transcription polymerase chain reaction and Western blot analyses demonstrated that Bmrn was expressed at higher levels in the epidermis than in other tissues tested, and it showed a very high expression level during metamorphosis. Knock-down of Bmrn produced defects in the tarsus and pretarsus, including the fusion and reduction of tarsomeres, and the developmental arrest of pretarsus. Our data showed that Bmrn is involved in the formation of the tarsus and pretarsus, whereas its homologous gene in Drosophila has been shown to affect three tarsal segments （t2-t4）, suggesting that the remodeling of the leg has involved changes in the patterning of gene regulation during evolution.

关键词： Bombyx mori limb / leg development pretarsus RNAi rotund/rn tarsus

Involvement of mitochondrial apoptotic pathway and MAPKs/NF-κB inflammatory pathway in the neuroprotective effect of atractylenolide Ⅲ in corticosterone-induced PC12 cells

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Chinese Journal of Natural Medicines 2019年第4期17卷 264-274页

作者： GONG Wen-xia zhou Yu-Zhi QIN Xue-Mei DU Guan-hua Modern Research Center for Traditional Chinese Medicine Shanxi University Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College

Atractylenolide Ⅲ(ATL-Ⅲ), a sesquiterpene compound isolated from Rhizoma Atractylodis Macrocephalae, has revealed a number of pharmacological properties including anti-inflammatory, anti-cancer activity, and neuroprotective effect. This study aimed to evaluate the cytoprotective efficiency and potential mechanisms of ATL-Ⅲ on corticosterone injured rat phaeochromocytoma(PC12) cells. Our results demonstrate that ATL-Ⅲ increases cell viability and reduces the release of lactate dehydrogenase(LDH). The results suggest that ATL-Ⅲ protects PC12 cells from corticosterone-induced injury by inhibiting the intracellular Ca^(2+) overloading, inhibiting the mitochondrial apoptotic pathway and modulating the MAPK/NF-κB inflammatory pathways. These findings provide a novel insight into the molecular mechanism by which ATL-Ⅲ protected the PC12 cells against corticosterone-induced injury for the first time. Our results provide the evidence that ATL-Ⅲ may serve as a therapeutic agent in the treatment of depression.

关键词： Depression Atractylenolide Ⅲ Corticosterone Apoptosis MAPKs NF-κB

Toxicity of Nanoscale CuO and ZnO to Daphnia magna

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Chemical Research in Chinese Universities 2012年第2期28卷 209-213页

作者： ZHAO Hai-zhou LU Guang-hua xia Jun JIN Shao-ge Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes Ministry of EducationCollege of EnvironmentHohai UniversityNanjing 210098P.R.China

The potential effects of nanoscale CuO（nCuO）,nanoscale ZnO（nZnO） and their mixtures on Daphnia magna were investigated,including 48-h acute toxicity and 21-d chronic toxicity tests as well as a feeding *** results of acute toxicity show that nCuO/nZnO mixture was the most toxic followed by nCuO and *** nanoparticles（NPs） inhibited both the growth and reproduction of Daphnia magna during the testing *** dependence was apparent in all the cases and the intrinsic rate of natural increase was confirmed to be a very sensitive parameter to NPs *** mixture appeared to be more toxic than the corresponding individual exposures at most cases except for the feeding behavior.

关键词： Daphnia magna Nanoparticle Binary mixture Toxicity

Feature analysis on US military aircraft engine advanced technology programs

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航空动力学报 2014年第7期29卷 1701-1709页

作者： LIANG Chun-hua SUN Ming-xia LIU Hong-xia Shenyang Engine Design and Research Institute Aviation Industry Corporation of China

US military aircraft engine advanced technology programs were overviewed and analyzed from light weight gas generator(LWGG)program initiated in 1960 sthrough integrated high performance turbine engine technology(IHPTET)program started in 1980 s,then to versatile affordable advanced turbine engine(VAATE)*** features and trends were summarized and concluded by literature statistics method,such as teams based on closely corporation among government,industries and academics,goals oriented with national defence strategies and weapon system development requirements,engineering manufacture and development including all relative disciplines and areas,verification measured by technology readiness level,the application extending to military aircraft engine,civilian engine,gas turbine and space vehicle,*** experience and lessons obtained can provide reference and guide for technology research and engineering manufacture and development of military aircraft engines in the world.

关键词： aircraft engine military aircraft engine advanced technology program technology corporation multi-discipline development technology verification

Orientation and Structure of Ionic Liquid Cation at Air/[bmim][BF4] Aqueous Solution Interface

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Chinese Journal of Chemical Physics 2013年第5期26卷 569-575,I0004页

作者： Gang-hua Deng xia Li You-qi Guo Shi-lin Liu zhou Lu Yuan Guo Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Tech-nology of China Hefei 230026 China Beifing National Laboratory for Molecular Sciences State Key Laboratory of Molecular ReactionDynamics Institute of Chemistry Chinese Academy of Sciences Belting 100190 China Nanjing University of Aeronautics and Astronautics NanjinE 211205 China

The watermiscible room temperature ionic liquid 1butyl3methylimidazolium tetrafluorob orate （[bmim] [BF4]） is a model system for studying the interactions between ionic liquid and water molecules. In this work the orientational structure of the low concentrated aqueous solution of [bmim] [BF4] at the air/liquid interface was investigated by sum frequency gener ation vibrational spectroscopy. It has been found that at very low concentrations, the butyl chain exhibited a significant gauche defect, indicating a disordered conformation; and the cation ring oriented with a fairly small tilting angle at the surface. When the concentration increased, the cation ring tended to lie flat at the surface, and the gauche defects of the butyl chain decreased due to the intermolecular chainchain interactions and the consequent more ordered interfacial molecular arrangement. Additionally, the antisymmetric stretching mode in the PPP and SPS spectra exhibited a peak shift, showing that there exists more than one kind of orientation or chemical environment for the butyl CH3 group. These results may shed new light on understanding the surface behavior of watermiscible ionic liquids as well as the imidazolium based surfactants.

关键词： Sum frequency generation vibratinal spectroscopy Ionic liquid Aqueous solu-tion Interface orientation

A Presumed Synonymous Mutation of PKD2 Caused Autosomal Dominant Polycystic Kidney Disease in a Chinese Family

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Current Medical Science 2021年第5期41卷 1029-1036页

作者： Lin-xia DENG Yuan YANG Jing YANG Luo-wen zhou Kang WANG Jian-hua zhou Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Forensic Medicine Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Autosomal dominant polycystic kidney disease(ADPKD)is mainly caused by the pathogenic mutation of PKD1 or PKD2 gene and usually affects bilateral *** mutations are generally assumed to be neutral as they do not alter amino ***,we described an extremely rare ADPKD child caused by a heterozygous synonymous mutation of PKD2 gene accompanied by massive proteinuria and congenital solitary ***:Clinical characteristics of the patients were ***-exome sequencing was performed to screen the disease-causing gene mutation,and reverse transcription polymerase chain reaction(RT-PCR)and Sanger sequencing were applied to analyze the impact of the identified mutation on gene transcription and ***:Polycystic changes were found in the solitary kidney of a girl initially presented with nephrotic-range *** her mother and 2 other family members were diagnosed to be ***-exome sequencing of the proband identified a heterozygous synonymous mutation(c.1716G>A,***572=)located in the splicing site of exon 7 in PKD2 gene,which was co-segregated with the PKD phenotype in the ***-PCR and direct sequencing of amplified products revealed that this heterozygous synonymous mutation led to exon7 skipping in PKD2 ***:We reported an extremely rare child case of ADPKD2 in combination with solitary kidney and nephrotic-range proteinuria,and firstly confirmed the pathogenicity of a heterozygous synonymous mutation(c.1716G>A)in PKD2 *** results indicate that synonymous mutations should not be excluded from disease-causing if they are located in splicing site of an exon.

关键词： autosomal dominant polycystic kidney disease child PKD2 gene splicing synonymous mutation

Formation mechanism of hierarchical twins in the CoCrNi medium entropy alloy

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Journal of Materials Science & Technology 2023年第9期140卷 19-32页

作者： Dongpeng hua xiaorong Liu Wan Wang Qing zhou Qiaosheng xia Shuo Li Junqin Shi Haifeng Wang State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’anShaanxi 710072PR China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’anShaanxi 710072PR China

The three-dimensional hierarchical twin network has been proved to be the source of the excellent strength-ductility combination in the CoCrNi medium entropy *** the formation mechanism of hierarchical twins,however,remains a challenge using either the post-mortem or the in-situ microstructural *** this study,the atomistic formation mechanism of hierarchical twins was investigated using molecular dynamics simulations,with special focus on the effects of strain rate and deformation *** to the primary twin boundaries kink-driven hierarchical twinning tendency in pure FCC metals,the chemical inhomogeneity in CoCrNi can reduce the necessary kink height to trigger conjugate twins(CTWs),fascinating the formation of twin *** room temperature,the plastic deformation is dominated by primary twins(PTWs)and conjugate slips at a relatively lower strain rate(e.g.,5×10^(7)s^(−1)).The hierarchical twins can be activated in cases of deforming at a higher strain rate(e.g.,2×10^(8)s^(−1)).Further increasing the strain rate(e.g.,1×10^(10) s^(−1))leads to the phase-transformation induced *** cryogenic temperatures,the hierarchical twins are promoted within a large range of strain rates(e.g.,5×10^(7)–1×10^(10) s^(−1)).A higher temperature leads to the synergy of CTWs and primary slips at a lower strain rate,but hierarchical twins at a higher strain *** this basis,a qualitative comparison and scalable trends between experiments and simulations were *** present study would not only provide the basic understanding for the twinning behavior found experimentally,but also contribute to the design of medium/high entropy alloys with excellent mechanical performances by tuning microstructures.

关键词： Hierarchical twin Medium entropy alloy Strain rate Deformation temperature Molecular dynamics simulation

Estimating the crop leaf area index using hyperspectral remote sensing

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Journal of Integrative Agriculture 2016年第2期15卷 475-491页

作者： LIU Ke zhou Qing-bo WU Wen-bin xia Tian TANG hua-jun Key Laboratory of Agri-Informatics Ministry of Agriculture Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Urban & Environmental Sciences Central China Normal University

The leaf area index（LAI） is an important vegetation parameter,which is used widely in many *** sensing techniques are known to be effective but inexpensive methods for estimating the LAI of crop *** the last two decades,hyperspectral remote sensing has been employed increasingly for crop LAI estimation,which requires unique technical procedures compared with conventional multispectral data,such as denoising and dimension ***,we provide a comprehensive and intensive overview of crop LAI estimation based on hyperspectral remote sensing ***,we compare hyperspectral data and multispectral data by highlighting their potential and limitations in LAI ***,we categorize the approaches used for crop LAI estimation based on hyperspectral data into three types：approaches based on statistical models,physical models（i.e.,canopy reflectance models）,and hybrid *** summarize and evaluate the theoretical basis and different methods employed by these approaches（e.g.,the characteristic parameters of LAI,regression methods for constructing statistical predictive models,commonly applied physical models,and inversion strategies for physical models）.Thus,numerous models and inversion strategies are organized in a clear conceptual ***,we highlight the technical difficulties that may hinder crop LAI estimation,such as the ＂curse of dimensionality＂ and the ill-posed ***,we discuss the prospects for future research based on the previous studies described in this review.

关键词： hyperspectral inversion leaf area index LAI retrieval

CORRELATION BETWEEN ASO AND AAO

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Journal of Hydrodynamics 2004年第5期16卷 544-547页

作者： LIUNa ZHANGQing-hua CHENHong-xia KeyLaboratoryofMarineScienceandNumericalmodeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China CollegeofPhysicalandEnvironmentOceanography OceanUniversityofChinaQingdao266003China

Using a 34 years database consisting of sea level pressure and sea iceconcentration, the relationship between Antarctic Oscillation (AAO) and Antarctic Sea-iceOscillation (ASO) was investigated. Firstly, Empirical Orthogonal Function (EOF) analysis depictsthe spatial variability of AAO and ASO and Antarctic Sea-ice Oscillation Index (ASOI) was definedfor the first time. Secondly, power spectrum and head-lag correlation analysis show that ASO and AAOhave the same periods of quasi-three years, quasi-one year and quasi-half a year. Corresponding toAAO, ASO has an evident anti-oscillation after one and half a year.

关键词： ASO AAO EOF power spectrum analysis correlation analysis