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Differential roles of seed and sprout regeneration in forest diversity and productivity after disturbance

Forest Ecosystems 2024年第3期11卷 371-380页

作者： Marek Mejstrík Martin svatek Martina Pollastrini Martin Sramek Radim Matula Department of Forest Ecology Faculty of Forestry and Wood SciencesCzech University of Life Sciences PragueKamýcka 12916500PragueCzech Republic Department of Forest Botany Dendrology and GeobiocoenologyFaculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 361300BrnoCzech Republic Department of Agriculture FoodEnvironment and ForestryUniversity of FirenzePiazzale Delle Cascine 2850144FirenzeItaly

Natural regeneration after disturbances is a key phase of forest development,which determines the trajectory of successional changes in tree species composition and *** trees can originate from either seeds or sprouts produced by disturbed trees with sprouting *** both regeneration strategies often develop and co-occur after a disturbance,they tend to affect forest development differently due to significant functional ***,the origin of tree regeneration is rarely distinguished in post-disturbance forest surveys and ecological studies,and the differential roles of seed and sprout regeneration in forest productivity and diversity remain poorly *** address these research gaps,we explored the role of sprout and seed regeneration in the formation of woody species diversity and above-ground biomass(AGB)productivity in early-stage forest *** were collected in two experimental forest stands in the Czech Republic,where trees were cut with varying intensities with the density of residual(uncut)trees ranging from 0 to 275 trees per *** trees were mapped and their sizes were measured before cutting and then,either as a stump with sprouts or a residual tree,remeasured 11 years *** addition,all tree saplings were mapped and measured 11 years after logging,and their origin(sprout or seed)was *** assess abundances and productivity,we estimated AGB of all2,685 sprouting stumps of 19 woody species and 504 generative(i.e.,seed origin)individuals of 16 woody species,using allometric ***-effects models were used to analyze the effects of each regeneration strategy on woody species diversity and the total AGB under varying densities of residual *** multidimensional scaling was used to evaluate the effect of regeneration strategies on species *** and diversity of sprouts were significantly higher than those of seed *** formed on average97.1%of

关键词： Resprouting Seeding Residual trees Tree diversity Above-ground biomass

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Numerical Simulation of Separated Flows in Channels

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Journal of Thermal Science 2012年第2期21卷 145-153页

作者： Petr Louda Jaromír Príhoda Petr sváek Karel Kozel Czech Technical University in Prague Fac. of Mechanical Engineering Karlovo nám. 13 CZ-121 35 Praha 2 institute of Thermomechanics AS CR v.v.i. Dolejkova 5 CZ-182 00 Praha 8

The work deals with numerical modelling of turbulent flows in channels with an expansion of the cross-section where flow separation and reattachment occur. The performance of several eddy viscosity models and an explicit algebraic Reynolds stress model (EARSM) is studied. The used test cases are flows in channels with various backward facing steps where the step is perpendicular or inclined and the top wall is parallel or deflected. Furthermore, a channel with the circular ramp is considered. The numerical solution is achieved by the finite volume method or by the finite element method. The results of both numerical approaches are compared.

关键词： backward facing step flow EARSM model SST model

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Numerical Simulation of Glottal Flow in interaction with Self Oscillating Vocal Folds:Comparison of Finite Element Approximationwith a Simplified Model

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Communications in Computational Physics 2012年第8期12卷 789-806页

作者： P.svácek J.Horácek Department of Technical Mathematics Faculty of Mechanical EngineeringCzech Technical University in PragueKarlovo nam.13Praha 212135Czech Republic institute of Thermomechanics Academy of Sciences of the Czech RepublicDolejskova 5Praha 8Czech Republic

in this paper the numerical method for solution of an aeroelastic model describing the interactions of air flow with vocal folds is *** flow is modelled by the incompressible Navier-Stokes equations spatially discretizedwith the aid of the stabilized finite element *** motion of the computational domain is treated with the aid of the Arbitrary Lagrangian Eulerian *** structure dynamics is replaced by a mechanically equivalent system with the two degrees of freedom governed by a system of ordinary differential equations and discretized in time with the aid of an implicit multistep method and strongly coupled with the flow *** influence of inlet/outlet boundary conditions is studied and the numerical analysis is performed and compared to the related results from literature.

关键词： Finite element method arbitrary Lagrangian-Eulerian method biomechanics of voice production

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identification and Characterization of glnA Promoter and its Corresponding Trans-regulatory Protein GlnR in the Rifamycin sv Producing Actinomycete,Amycolatopsis mediterranei U32

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 831-843页

作者： Hao YU~(1&) Wen-Tao PENG~1 Yang LiU~1 Ting WU~2 Yu-Feng YAO~1 Ming-Xue CUi~1 Wei-Hong JiANG~1 Guo-Ping ZHAO~(1,3,4*) 1 Laboratory of Molecular Microbiology,institute of Plant Physiology and Ecology,Shanghai institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200032,China 2 Department of Medicinal Chemistry,School of Pharmacy,Fudan University,Shanghai 200032,China 3 State Key Laboratory of Genetic Engineering & Department of Microbiology,School of Life Science,Fudan University,Shanghai 200433,China 4 Laboratory of Disease and Health Genomics,Chinese National Human Genome Center at Shanghai,Shanghai 201203,China Laboratory of Molecular Microbiology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China State Key Laboratory of Genetic Engineering & Department of Microbiology School of Life Science Fudan University Shanghai 200433 China Laboratory of Disease and Health Genomics Chinese National Human Genome Center at Shanghai Shanghai 201203 China

The genetic requirements for the transcription of glnA,encoding the major glutaminesynthetase in a rifamycin sv-producing Amycolatopsis mediterranei strain,U32,were *** experiments showed that the promoter of U32 glnA （pglnA） was likely to have two transcriptioninitiation sites:P1and P2,located 157 and 45 nucleotides （nt） upstream of the translational start codon,*** mobility shift and DNase i footprinting analyses revealed a 30 bp cis-element locatedat 45 to 75 nt downstream of P1,or 38 to 68 nt upstream of *** sequence of the cis-element displayedhigh similarity to the corresponding regions of pglnA from Streptomyces coelicolor and *** as a reporter gene,the expression levels of U32 pglnA and its deletion derivatives under differentnitrogen-source conditions were analyzed by detecting the catechol dioxygenase activities in ***54,*** J508 and *** FS10 （glnR mutant）.These in vivo studies showed that theactivation of U32 pglnA in *** required GlnR,and its binding to the U32 pglnA was furtherconfirmed by the gel mobility shift *** and heterologous expression of the U32 glnR allowed usto detect the in vitro interaction between the U32 GlnR and the corresponding pglnA *** shown by in vivo glnR inactivation and complementation indicated that GlnR is essential for theactive transcription of glnA in U32.

关键词： glnA promoter cis-element glnR Amycolatopsis mediterranei

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The effect of melt flow induced by RMF on the meso-and micro-structure of unidirectionally solidified Al–7wt.%Si alloy Benchmark experiment under magnetic stirring

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Journal of Materials Science & Technology 2022年第8期103卷 197-208页

作者： Zs.Veres A.Roósz A.Rónaföldi A.Sycheva M.svéda University of Miskolc Institute of Physical MetallurgyMetal Forming and Nanotechnology(UM)Hungary MTA-ME Materials Science Research Group ELKHHungary

During the last two decades,many algorithms were developed to simulate the solidification process for different casting methods like ingots,continuous casting of steel and the direct chill cast of *** performed under exactly known conditions and with the detailed knowledge of meso-and micro-structures are required for validating these *** aim of this paper is to give a data set to validate these *** solidification experiments were performed by using a rotating magnetic field(RMF)to study the effect of melt flow on the solidified micro-and meso-structure of the Al-7wt.%Si binary *** first and the third 1/3 parts of samples were solidified without magnetic stirring,and the second(middle)1/3 part was solidified by using magnetic *** magnetic induction was 10 m T,the temperature gradient was~7 K/mm,and the sample movement velocity was 0.1 mm/*** the longitudinal section of the sample,the columnar/equiaxed transition(CET),the equiaxed/columnar transition(ECT),the secondary dendrite arm spacing(SDAS),and the macrosegregation(concentration distribution and the amount of eutectic)were *** primary dendrite arm spacing(PDAS)and the grain structure were studied on the cross-section after color etching.

关键词： Al–7wt.%Si alloy Unidirectional solidification RMF magnetic stirring Meso-and microstructure

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Purification, characterization and evaluation of insecticidal activity of trypsin inhibitor from Albizia lebbeck seeds

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Journal of Forestry Research 2012年第1期23卷 131-137页

作者： Pratima Sharma Amarjit K Nath Reena Kumari sv Bhardwaj Department of Biotechnology UHFNauniSolanIndia

A Bowman-Birk inhibitor with activity against gut proteases of Helicoverpa armigera was extracted in 0.i M sodium phosphate buffer from defatted seed flour of Albizia lebbeck. it was purified to 29.62 folds with 51.43% recovery using ammonium sulfate precipitation, gel filtration chromatography on Sephadex G-100 column and ion ex- change chromatography on DEAE-Sephadex As0. The purified protein had a molecular weight of 12,303 daltons as determined by SDS-PAGE. it was found to be heat stable up to 60~C and had two pH optima of 7.5 and 9.0. The inhibitor exhibited non-competitive pattern of inhibition with a low Ki value of 0.2 ~tM. The inhibitoi- was found to be susceptible to varying concentrations of reducing agents like DTT and 2- mercaptoethanol, thereby indicating the role of disulphide bridges in maintaining its three dimensional structure and stability. The purified inhibitor caused mortality and suppressed larval growth ofPieris brassi- cae larvae. it was also found to be effective against gut trypsin extracted from Spodoptera littoralis. The sequence of the genes encoding for such inhibitors can be determined and the genes expressing protease inhibitors can be used in vegetable crops to confer resistance against insect pests and other plant pathogens.

关键词： Albizia lebbeck trypsin inhibitor insecticidal activity purifi-cation Pieris brassicae

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Relationship between interleukin-1 type i and 2 receptor gene polymorphisms and the expression level of membrane-bound receptors

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Cellular & Molecular immunology 2015年第2期12卷 222-230页

作者： FF Vasilyev AN Silkov sv Sennikov Laboratory of Molecular immunology Federal State Budgetary Institution 'Research Institute of Clinical Immunology' Russian Academy of Medical Sciences Siberian Branch. Novosibirsk. Russia

The biological activity of the multifunctional cytokine interleukin-1 （iL-1） is mediated by its receptors. The aim of this study was to determine if an association exists between single nucleotide polymorphisms （SNPs） in the iL-1 type i and 2 receptor genes （iLiR1 and iLiR2） and the expression level of membrane-bound iLiRs on subpopulations of mononuclear cells or serum levels of soluble iL-1 receptors. it was observed that healthy individuals with the genotype TT in SNP rs2234650.C〉T had a lower percentage of intact CD14＋ monocytes expressing iLiR1 on their surface. The SNP rs4141134-T〉C in iLiR2 has also been associated with the percentage of intact CD3＋ T cells expressing iLiR2. Furthermore, individuals carrying the CC allele of SNP rs4141134.T〉C and the TT allele of SNP rs2071008-T〉G in iLiR2 had a lower density of iLiR2s on the surface of CD14＋ monocytes in lipopolysaccharide （LPS）-stimulated PBMC cultures. in summary, this study demonstrated that iL-1 receptor gene polymorphisms could be one of the factors influencing the expression of membrane-bound iL-1 receptors （iLiR） on immunocompetent cells.

关键词： interleukin-1 membrane-bound receptor SNPs soluble receptor

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Effects of Cu^(2+) on characteristic of sv currents

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Science China Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1,2 & YANG Pin1 1. Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, institute of Molecular Science, Shanxi University, Taiyuan 030006, China 2. institute of Environment Science, Taiyuan University of Science and Technology, Taiyuan 030024, China Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2+ on Slow Vacuolar (sv) current’s characteristic. Our results show that Cu2+ in bath solution at higher concentration inhibits sv currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2+ significantly promotes the sv currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2+. These results show that there may be some Cu2+ binding sites on sv channels and binding to which can change sv current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2+, sv channel.

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Nonlinear dynamics of self-oscillating polymer gels

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Science China(Technological Sciences) 2010年第7期53卷 1862-1868页

作者： WANG PengFei1, ZHOU JinXiong1, Li MeiE2, XU Feng1,3 & LU TianJian1 1 Biomedical Engineering and Biomechanics Center, sv Laboratory, Xi’an Jiaotong University, Xi’an 710049, China 2 School of Materials Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China 3 HST Center for Biomedical Engineering, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, 510660, USA Biomedical Engineering and Biomechanics Center SV Laboratory Xi’an Jiaotong University Xi’an China School of Materials Science and Engineering Xi’an Jiaotong University Xi’an China HST Center for Biomedical Engineering Department of Medicine Brigham and Women’s Hospital Harvard Medical School Boston USA

Self-oscillating polymer gels driven by Belousov-Zhabotinsky (BZ) chemical reaction are a new class of functional gels that have a wide range of potential applications (e.g., autonomously functioning membranes, actuate artificial muscles). However, the precise control of these gels has been an issue due to limited investigations of the influences of key system parameters on the characteristics of BZ gels. To address this deficiency, we studied the self-oscillating behavior of BZ gels using the nonline-ar dynamics theory and an Oregonator-like model, with focus placed upon the influences of various system parameters. The analysis of the oscillation phase indicated that the dynamic response of BZ gels represents the classical limit cycle oscillation. We then investigated the characteristics of the limit cycle oscillation and quantified the influences of key parameters (i.e., ini-tial reactant concentration, oxidation and reduction rate of catalyst, and response coefficient) on the self-oscillating behavior of BZ gels. The results demonstrated that sustained limit cycle oscillation of BZ gels can be achieved only when these key pa-rameters meet certain requirements, and that the pattern, period and amplitude of the oscillation are significantly influenced by these parameters. The results obtained in this study could enable the controlled self-oscillation of BZ gels system. This has several potential applications such as controlled drug delivery, miniature peristaltic pumps and microactuators.

关键词： Belousov-Zhabotinsky reaction self-oscillating gels numerical simulation limit cycle parameter analysis

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Sub-seasonal variability of Luzon Strait Transport in a high resolution global model

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Acta Oceanologica Sinica 2010年第3期29卷 9-17页

作者： ZHANG Zhengguang ZHAO Wei LiU Qinyu Physical Oceanography Laboratory Ocean University of China Qingdao 266100 China

The Luzon Strait is the main impact pathway of the Kuroshio on the circulation in South China Sea （SCS）. Based on the analysis of the 1997–2007 altimeter data and 2005–2006 output data from a high resolution global HYCOM model, the total Luzon Strait Transport （LST） has remarkable subseasonal oscillations with a typical period of 90 to 120 days, and an average value of 1.9 sv into SCS. Further spectrum analysis shows that the temporal variability of the LST at different depth is remarkable different. in the upper layer （0–300 m）, westward inflow has significant seasonal and subseasonal variability. in the bottom layer （below 1 200 m）, eastward outflow exhibits remarkable seasonal variability, while subseasonal variability is also clear. in the intermediate layer, the westward inflow is slightly bigger than the eastward outflow, and both of them have obvious seasonal and subseasonal variability. Because the seasonal variation of westward inflow and eastward outflow is opposite, the total transport of intermediate layer exhibits significant 50–150 days variation, without obvious seasonal signals. The westward Rossby waves with a period of 90 to 120 days in the Western Pacific have very clear correlationship with the Luzon Strait Transport, this indicates that the interaction between these westward Rossby waves and Kuroshio might be the possible mechanism of the subseasonal variation of the LST.

关键词： Luzon Strait Transport subseasonal variability Rossby waves

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