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Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki fra.z binder Torben Hilmers zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSIRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

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Only mothers feed mature offspring in European Ceratina bees

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Insect Science 2021年第5期28卷 1468-1481页

作者： Michael Mikat Jitka Waldhauserova Tereza frankova Katerina Cermakova Vojtech Broz Simon zeman Marcela Dokulilova Jakub Straka Department of zoology Faculty of ScienceCharles UniversityPragueCzech Republic Jihlava Grammar School JihlavaCzech Republic Department of Ecology Faculty of ScienceCharles UniversityPragueCzech Republic

Parental care directed to adult offspring is uncommon in *** parental care has been documented in Xylocopinae bees(Hymenoptera:Apidae).Moreover,some Ceratina bees(Xylocopinae)are known to feed mature siblings,and feeding of mature siblings is achieved by dwarf eldest daughters when mothers *** daughters are intentionally malnourished by mothers and usually originate from the first brood ***,we examined the pattern of care prov ided to young adults in three small European carpenter bees:Ceratina(Ceratina)cucurbitina,C.(Euceratina)chalybea,and C.(E.)*** of nest departures and arrivals were performed to study foraging *** detected intensive foraging behavior of mothers in all three studied ***,we did not observe regular foraging bchavior of daughters in any *** experimental removal of mothers in *** led to the emigration of young adults and did not initiate foraging activity in *** conclude that the feeding of siblings does not occur in these species unlike in the American species *** detected female-biased sex ratios in the first brood cell in *** and *** offspring in the first brood cell was smaller than other female offspring only in *** results show that a female-biased sex ratio and the small size of daughters in the first brood cell do not provide sufficient ev idence for demonstrating the existence of an altruistic daughter and also that the pattern of maternal investment is not exclusively shaped by social interactions.

关键词： foraging trip Hymenoptera maternal care provisioning sociality Xylocopinae

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Research of Neural Network Based on Improved PSO Algorithm for Carbonation Depth Prediction of Concrete

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武汉理工大学学报 2010年第17期32卷 170-175页

作者： DAI W SHUI z H School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China School of Economics and Management Huangshi Institution of TechnologyHuangshi 435003China

Firstly,neural network based on improved particle swarm optimization (PSO)algorithm is introduced in this paper. Based on the data collected from projects in typical areas,the concrete carbonation depth is assessed with consideration of various factors such as unit cement consumption (C),unit water consumption (W),binder material content (B),water binder ratio (W/B ),concrete strength (MPa),rapid carbonization days (D),fly ash consumption of unit volume concrete(FA),fly ash percentage of total cementitious materials (FA%),expansion agent consumption of unit volume concrete(EA),expansion agent percentage of total cementitious materials (FA%).Gaining the data from project-experiment,a model is presented to calculate and forecast carbonation depth using neural network based on improved PSO algorithm. The calculation results indicate that this algorithm accord with the prediction carbonation depth of concrete accuracy requirements and has a better convergence and generalization,worth being popularized.

关键词： PSO BP neural network concrete carbonation depth prediction

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The synthesis of dialdehydes from dicarboxylic acids via imidazolines

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Chinese Science Bulletin 1997年第2期42卷 130-132页

作者： Shi, z Gu, H Xu, LL Department of Chemistry Northwest University Xi’an China

DIALDEHYDES are important chemical industrial materials, which are widely used in textile,medicine, dye, binder, coating and so on. The traditional method for preparing dialdehydes is the catalytic oxidation of glycol. We have reported the reduction ring-opening reaction of inndazoline by NaBH4.In this note, the reduction of imidazoline by sodium and ethanol is studied. A new synthetic method for the preparation of dialdehydes from dicarboxylic acids

关键词： dicarboxylic acid imidazoline dialdehyde new synthetic method.

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Preparation and Microstructure Analysis of High Strength Cementitious Materials Containing Metakaolin

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武汉理工大学学报 2010年第17期32卷 117-122,136页

作者： YU R SHUI z H DONG J School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The preparation and microstructure analysis of high strength cementitious materials containing metakaolin (MK) was studied in this paper. The MK was prepared firstly,and then was mixed with fly ash,ground blast furnace slag,quartz powder and cement with different percentage to produce high strength cementitious materials. After cured under different environment,the compressive strength of such materials was tested. Techniques of X-ray diffraction (XRD) and scanning electron microscopy (SEM) were further employed to identify the composition and microstructure. The results obtained reveal that the compressive strength of such materials mainly effected by component of raw materials,the water binder ratio (W/B) and the curing regime. When the three factors above are optimized,the compressive strength of such materials can get to 156 MPa in maximum. The X-ray diffraction analysis and the scanning electron microscopic images indicated that under optimal curing condition,more raw materials can take chemical reaction and the microstructure is dense to yield good mechanical properties.

关键词： preparation microstructure analysis high strength cementitious materials metakaolin

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Freeze-thaw Resistance of Concrete in Seawater

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武汉理工大学学报 2010年第17期32卷 108-111页

作者： SHUI z H XU H G zHAN B J School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Transportation Bureau of Xinganmeng Inner Mongolia Ulanhot 137400China

The effect of freeze-thaw cycles in seawater on the performance of concrete was studied in this paper. Concrete samples with different water binder ratio and different component were prepared,and were then put into fresh water and synthesized seawater. After the experiments of freeze-thaw cycles,the mass loss,relative dynamic elastic modulus (RDEM) and compressive strength of each sample were tested. The results obtained reveal that with the increase of the water binder ratio,the resistance ability of freeze-thaw impact in seawater of concrete decrease dramatically. When the concrete contain 15% fly ash and 20% slag,its resistance ability to the freeze-thaw impact in seawater is the optimal. Compared to the seawater corrosion,the impact of freeze-thaw cycles to the properties of concrete is severer.

关键词： freeze-thaw damage seawater mass loss relative dynamic elastic modulus

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STUDY ON THE SURFACE MODIFICATION OF NANOMETER CARBON PARTICLES IN ATMOSPHERIC PLASMA

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 177-181页

作者： Y.J. Ge, G.Q. zhang, Y.M. Liu, X.G. Guo and z.F. zhao Beijing Institute of Printing, Beijing 102600, China Beijing Inst. of Printing Beijing 102600 China

The surface modification of nanometer carbon material has been studied by using an Induced Dielectric Barrier Discharge Plasma device (IDBD). The experimental results show that with different work gases and different discharge conditions, the surface behaviors of carbon black can be changed according to needs, including the use of different functional groups and the change of the surface roughness of carbon particles etc., which increased the grinding and dispersion abilities in binder.

关键词： surface modification. nanometer material IDBD plasma. carbon black

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Composite Stable to Corrosive Media in SiC-AL2O3-Si2ON2System

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Journal of Electronics Cooling and Thermal Control 2013年第2期3卷 74-84页

作者： z. D. Kovziridze N. S. Nizharadze G. Tabatadze M. Mshvildadze E. Nikoleishvili z. Mestvirishvili Department of Chemical and Biological Technologies Georgian Technical University Tbilisi Georgia

The object of the research was to study the composite received in impure nitrogen medium from silicon carbide, silicon and refractory clay mixture. With X-ray diffraction, petrographic and electron microscope methods the chemical processes happening at burning of the mentioned mixture in technical nitrogen medium and the kind of received binder, phase composition and basic properties are studied. It is stated that silicon carbide composite with complex binder is received, the main phases being: Si2ON2, 3Al2O3· 2SiO2 and SiO2. SiC-Al2O3 composite is also received and studied. Water and acid resistance of composites (H2SO4, r—1.84 g/sm3) and resistance to nonferrous metals and slag are studied. The received composites can be used for production of protective envelope of thermocouple for measuring of temperature of ferrous and nonferrous metals at high temperatures.

关键词： Composite Silicon Carbide Nitrogen Area Silicon Oxynitride Resistance

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Leadership practices inventory (LPI)

Leadership practices inventory (LPI)

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1000年

作者： James M. Kouzes Barry z. Posner.

来源：畅想之星图书光盘版（南... 评论

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An In Vitro Model of Perineural Invasion of Adenoid Cystic Carcinoma

An In Vitro Model of Perineural Invasion of Adenoid Cystic C...

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第八次全国口腔颌面—头颈肿瘤会议

作者： Shao z Shang zJ (Department of Oral and Maxillofacial Surgery,School and Hospital of Stomatology,Wuhan University,Wuhan,PR China)

Background & Objectives:Preineural invasion is the major mechanism of adenoid cystic carcinoma(ACC) spread outside the salivary *** is understood regarding mechanisms of perineural invasion in *** present an in vitro model to observe the interaction between nerves and ACC ***:Mouse dorsal root ganglia(DRG) and human ACC-M cell lines were co-cultured in Matrigel *** cultures consisted ACC cells only and DRG *** outgrowth,cell colony growth,neurite-cell contact,and retrograde extension were quantitated with dark phase microscopy.A modified MTT assay and Transwell assays were performed to determine the proliferation and migration alteration of ACC cells using the conditioned media from perineural invasion model. Results:Directional outgrowth of neurites was observed projecting into ACC-M colonies within 72 hr of *** the contact was established neurite growth diminished,suggesting an active attraction between neutrie and ACC ***,ACC cells migrated along neurites in a retrograde fashion into nerve establishing perineural *** addition to perineural invasion,ACC-M colony growth was elevated in regions near the DRG rclative to regions fra away from the DRG in *** conditioned media from perineural invasion model could induce the ACC cells survival and ***:This study shows the in vitro model of perineural invasion of adenoid cystic *** model can be used to study specific mechanism of ACC cell-nerve interaction. These data suggest that the process of perineural invasion involve active and reciprocal interactions between ACC cells and nerves and ACC cells acquire a survival and migration advantage by contact with neuritis.

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