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On the effect of turbulent anisotropy on pulsation stability of stars

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Research in Astronomy and Astrophysics 2017年第3期17卷 77-86页

作者： Chun-Guang Zhang Li-cai Deng da-Run Xiong Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences Purple Mountain Observatory Chinese Academy of Sciences

Within the framework of a non-local time-dependent stellar convection theory, we study in detail the effect of turbulent anisotropy on stellar pulsation stability. The results show that anisotropy has no substantial influence on pulsation stability of g modes and low-order （radial order nr 〈 5） p modes. The effect of turbulent anisotropy increases as the radial order increases. When turbulent anisotropy is neglected, most high-order （nr 〉 5） p modes of all low-temperature stars become unstable. Fortunately, within a wide range of the anisotropic parameter c3, stellar pulsation stability is not sensitive to the specific value of ca. Therefore it is safe to say that ca.ibration errors of the convective parameter ca do not cause any uncertainty in the calculation of stellar pulsation stability.

关键词： convection- stars: interiors - stars: oscillations

influence of Electrolyte Composition on the calcium-Phosphorus compound Coating on Titanium Substrate by Micro-arc Oxidation

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材料热处理学报 2004年第5B期25卷 1064-1067页

作者： ZHUXiu-hong WANGCong-zeng KOUBin-da SUXue-kuan ZHANGWen-quan CollegeofMaterialsScienceandEngineering BeijingUniversityofTechnologyBeijingChina

The compound bioceramic coating containing calcium (ca) and phosphorus (P) on titanium alloy substrate was prepared by means of micro-arc oxidation (MAO) treatment. The results show that under the different electrolyte the coating with the color of gray or black and surface morphology of cauliflower or honeycomb, where ca content and P contain can attain 30% and 20% respectively, can be obtained. Meanwhile, the influences of electrolyte temperature, current density and discharge time on morphology and thickness of coating are also discussed here.

关键词：微电弧氧化钛合金磷涂层钙涂层陶瓷涂层

Long-noncoding RNAs(lncRNAs) in drug metabolism and disposition, implica.ions in cancer chemo-resistance

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Acta Pharmaceutica Sinica B 2020年第1期10卷 105-112页

作者： Yue Wang Zihui Fang Mei Hong da Yang Wen Xie Center for Pharmacogenetics and Department of Pharmaceutical Sciences University of PittsburghPittsburghPA 15261USA College of Life Sciences South China Agricultural UniversityGuangzhou 510642China University of Pittsburgh cancer institute University of PittsburghPittsburghPA 15261USA Department of Computational and System Biology University of PittsburghPittsburghPA 15261USA Department of Pharmacology and Chemical Biology University of PittsburghPittsburghPA 15261USA

Drug metabolism is an orchestrated process in which drugs are metabolized and disposed through a series of specialized enzymes and *** in the expression and/or activity of these enzymes and transporters can affect the bioavailability(pharmacokinetics,or PK)and therapeutic efficacy(pharmacodynamics,or PD)of *** studies have suggested that the long non-coding RNAs(incRNAs)are highly relevant to drug metabolism and drug resistance,including chemoresistance in cancers,through the regulation of drug metabolism and disposition related *** review summarizes the regulation of enzymes,transporters,or regulatory proteins involved in drug metabolism by incRNAs,with a particular emphasis on drug metabolism and chemo-resistance in cancer *** perspective strategies to integrate multi-dimensional pharmacogenomics data for future in-depth analysis of drug metabolism related incRNAs are also *** the role of incRNAs in drug metabolism will not only facilitate the identifica.ion of novel regulatory mechanisms,but also enable the discovery of incRNA-based biomarkers and drug targets to personalize and improve the therapeutic outcome of patients,including cancer patients.

关键词： LncRNA Drug metabolism Chemo-resistance Xenobiotic receptor Regulation

On the fracture resistance of adhesively jointing structures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第8期7卷 1289-1295页

作者： ZHOU Zhi-qiang YANG Qing-da CHEN Wel-qlu Department of Civll Engineering. Zhejiang University Hangzhou 310027 China Rockweell Scientific Co. LLC 1049 Camino Dos Rios Thousand Oaks CA 91360 USA

The interface toughness of adhesively bonded structural members is one of the critical parameters for adhesive joint design. it is often assumed that the joint toughness is a material constant so that its value can be obtained from fracture tests of simple geometries such as DCB for Mode-Ⅰ, ENF for Mode-Ⅱ, using linear elastic fracture mechanics （LEFM）. However, the LEFM assumption of point-wise crack-tip fracture process is overly simplistic and may cause significant error in interpreting fracture test data. in this paper, the accuracy and applica.ility of various traditional beam-bending-theory based methods for fracture toughness evaluation, such as simple beam theory （SBT）, corrected beam theory （CBT） and experimental compliance method （ECM）, were assessed using the cohesive zone modelling （CZM） approach. it was demonstrated that the fracture process zone （FPZ） size has profound influence on toughness calculation and unfortunately, all the classic beam-bending theories based methods fail to include this important element and are erroneous especially when the ratio of crack length to FPZ size is relatively small （〈5.0）. it has also been demonstrated that after the FPZ size is incorporated into simple beam formulations, they provide much improved evaluation for fracture toughness. Formulation of first order estimate of FPZ size is aiso given in this paper.

关键词： Fracture mechanics Adhesive Cohesive zone model (CZM)

湖北省巴东县古树资源组成及其空间分布特征研究

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中国园林 2024年第5期40卷 138-144页

作者：王沛然游桂璇诸葛名名达良俊胡远东东北林业大学园林学院哈尔滨150040 西安建筑科技大学交叉院干旱区与半干旱区生态科学与工程研究院西安710055 华东师范大学上海市城市化生态过程与生态恢复重点实验室华东师范大学上海崇明生态研究院生态保育与恢复中心华东师范大学自然资源部大都市区国士空间生态修复工程技术创新中心东北林业大学黑龙江省园林植物种质资源开发与景观生态修复重点实验室

古树是全球生物多样性的重要组成部分,也是地方文化的重要载体。在全球生物多样性不断丧失尤其是古树资源持续减少的背景下,研究现存古树资源的组成和空间分布特征对古树的保育和生物多样性维持具有重要意义,同时为地区发展规划提供物... 详细信息

古树是全球生物多样性的重要组成部分,也是地方文化的重要载体。在全球生物多样性不断丧失尤其是古树资源持续减少的背景下,研究现存古树资源的组成和空间分布特征对古树的保育和生物多样性维持具有重要意义,同时为地区发展规划提供物种资源。以中国典型少数民族聚居地湖北省巴东县的古树资源为研究对象,结合野外调查和历史文献查阅,分析了巴东县古树的物种多样性、空间分布格局及其影响因素,探讨了巴东县古树保护面临的挑战与策略。结果表明,共记录古树2192株,隶属41科85属121种,所含物种数量较多的是壳斗科、松科、蔷薇科、木兰科和樟科,地理分布区系整体呈现由热带向温带过渡的特点;优势物种包括核桃、银杏和油杉;包含国家级保护物种17种;三级古树的个体数和物种数均超过一级和二级古树;古树胸径主要介于40~100cm,冠幅集中于10~17m,树高大多为15~25m;不同乡镇内分布的古树数量和物种数的差异显著,且大多分布在林地、耕地和未利用土地内。巴东县古树保护总体较好,95%以上的古树长势良好;海拔高度、坡度、人口密度、土地利用方式和文化习俗是影响巴东县古树资源组成和分布的主要因素;分级保护、分类保护、环境保护教育和差异性保护性有利于古树资源的留存和合理利用。

关键词：园林植物古树资源物种多样性分布格局留存机制巴东县

Downward surface shortwave radiation over the subtropical Asia-Pacific region simulated by CMiP5 models

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Atmospheric and Oceanic Science Letters 2017年第2期10卷 130-137页

作者： WANG Lei-Di LV da-Ren College of Agriculture South China Agricultural University Guangzhou China Plateau Atmosphere and Environment Key Laboratory of Sichuan Province Chengdu University of Information Technology Chengdu China Key Laboratory of Middle Atmosphere and Global Environmental Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The downward surface shortwave radiation （DSSR） over the subtropical Asia-Pacific region simulated by the historical experiments of 15 CMiPS models is evaluated in this *** simulated DSSR is compared against two satellite observational datasets, and the possible causes for the DSSR bias of the models are further investigated by dividing the subtropical Asia-Pacific region into five areas. Most of the CMiP5 models underestimate DSSR over the oceans, but overestimate DSSR over land. Aside from the Mediterranean-West Asia （MWA） and Central Asia （ca） areas, both the biases in annual and seasonal mean DSSR are well explained by the bias in surface shortwave cloud radiative forcing （CRF）, with an overestimation of the CRF effect over the subtropical North Pacific but an underestimation over other land regions. The effect of cloud plays a dominant role over the subtropical Asia-Pacific region, with relatively weaker influences over MWA and ca.in boreal summer and fall.

关键词： CMiPS surface shortwave radiation cloud radiative forcing

Litter removal impacts on soil biodiversity and eucalypt plantation development in the seasonal tropics

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Journal of Forestry Research 2023年第3期34卷 735-748页

作者： Jonas inkotte Barbara Bomfim Sarah camelo da Silva Marco Bruno Xavier Valadão Márcio Gonçalves da Rosa Roberta Batista Viana Alcides Gatto Reginaldo SPereira Department of Forestry Engineering University of BrasiliaBrasíliaDistrito FederalBrazil Climate and Ecosystem Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA SESi/SENAi Social Service industry Santa Catarina StateChapecóBrazil

The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic ***,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and *** two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area *** litterfall rates in juvenile and mature stands did not change with litter removal over the study *** litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control *** wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in *** years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to *** the mature stand,total ca.ion exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional sca.ing ordination revealed an increased homogeneity in epigeic fauna where litter was ***,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control p

关键词： Cerrado Nutrient cycling Soil ecology Soil epigeic fauna Plantation management

Supramolecular Vesicles Based on Water-Soluble 2,6-Helic[6]arene:High Affinity Binding,Stimuli Responsiveness and Delivery of Doxorubicin to cancer Cells

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Chinese Journal of Chemistry 2019年第6期37卷 575-580页

作者： Xuan Yang Weipeng Mao Yamin Liu Libai Li da Ma Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

Water-soluble 2,6-helic[6]arene was used to construct supramolecular vesicles via host-guest interaction. Water-soluble 2,6-helic[6]arene was discovered to be high affinity host for suitable biomarkers. Supramolecular vesicles were responsive to multiple stimuli types, including temperature, pH, ca^2+, CO2 bubbling and biomarker displacement. Supramolecular vesicles were used to load and deliver anti-tumor drug doxorubicin to HeLa cells in vitro.

关键词： host-guest systems nanostructures molecular recognitions self-assembly supramolecular vesicles

Evolution, Migration, Controlling Factors and Forming Setting of Mesozoic Basins in Western Shandong

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Acta Geologica Sinica(English Edition) 2005年第4期79卷 519-532页

作者： ZHANG Zhongyi WU Ganguo GUO Jinghui ZHANG da Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology Ministry of Education University of Geosciences Beijing 100083 institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029

The distinctive topography in western Shandong province consists of several NW-WNW-trending mountain ranges and intervening basins. Basins, in which late-stage sediments to the south have progressively overlapped the earlier sediments and ＂basement＂ rocks of the hanging-wall block, are bounded by S-SW-dipping normal faults to the north. Basin analysis reveals the Jurassic-Cretaceous sedimentary rocks accumulated both within the area of crustal extension and during extensional deformation; they contain a record of a sequence of tectonic events during stretching and can be divided into four tectonic-sequence episodes. These basins were initially developed as early as ca. 200 Ma in the northern part of the study area, extending dominantly N-S from the Early Jurassic until the Late Cretaceous. Although with a brief hiatus due to changes in stress field, to keep uniform N-S extensional polarity in such a long time as 130 Ma requires a relatively stable tectonic controlling factor responsible for the NW- and E-W-extensional basins. The formation of the extensional basins is partly concurrent with regional magmatism, but preceded magmatism by 40 Ma. This precludes a genetic link between local magmatism and extension during the Mesozoic. Based on integrated studies of basins and deformation, we consider that the gravitational collapse of the early overthickened continental crust may be the main tectonic driver for the Mesozoic extensional basins. From the Early Jurassic, dramatic reduction in north-south horizontal compressive stress made the western Shandong deformation belt switch from a state of failure under shortening to one dominated by extension and the belt gravitationally collapsed and horizontally spread to the south until equilibrium was established; synchronously, the normal faults and basins were developed based on the model of simple-shear extensional deformation. This may be relative to the gravitational collapse of the Mesozoic plateau in eastern China.

关键词： Mesozoic basin basin analysis extension gravitational collapse western Shandong