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

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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

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

Role of N-acetylcysteine in rifampicin-induced hepatic injury of young rats

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World Journal of Gastroenterology 2006年第2期12卷 287-291页

作者： sv Rana S Attri k Vaiphei R Pal A Attri k Singh Department of Gastroenterology Postgraduate Institute of Medical Education and ResearchChandigarh-160012India Department of Palhotogy Postgraduate Institute of Medical Education and ResearchChandigarh-160012India. Department of Surgery Govt. Medical CollegeCha-ndigarh-160012India

AIM, To study the role of N-acetylcysteine （NAC） as a protective agent in rifampicin （RMP）-induced oxidative hepatic injury of young rats. METHODS： Hepatic injury was produced by giving 50mg/kg body weight/day of RMP for 3 wk. A dose of NAC （100mg/kg body weight/day） was given in combination with RMP intraperitoneally. Analysis of lipid peroxidation, thiol levels, cytochrome P4se, superoxide dismutase （SOD）, catalase, glutathione peroxidase, reductase and transferase were estimated in liver along with the body weight, liver weight and histological observations. RESULTS： RMP exposure resulted in no change in body and liver weight while antioxidative enzymes were altered but the non protein thiol （GSH） status was well preserved. Cytochrome P450 system and peroxidation of lipids were induced by RMP exposure. Partial protection was observed with NAC against RMP-induced changes in liver, which was evidenced from the prevention of increase in lipid peroxidation and the reduction in SOD and catalase enzyme levels. CONCLUSION. NAC protects young rats against RMP- induced oxidative hepatic injury.

关键词： Rifampicin N-acetylcysteine Hepatoprotection

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

Is the ballan wrasse (Labrus bergylta) two species? Genetic analysis reveals within-species divergence associated with plain and spotted morphotype frequencies

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Integrative Zoology 2016年第2期11卷 162-172页

作者： María QUINTELA Elin Annie DANIELSEN Lua LOPEZ Rodolfo BARREIRO Terje svÅSAND Halvor kNUTSEN Anne Berit SkIFTEsvIk kevin A.GLOVER Institute of Marine Research BergenNorway Grupo de investigación BIOCOST University of A CoruñaSpain Centre for Ecological and Evolutionary Synthesis Department of BiologyUniversity of OsloOsloNorway University of Agder KristiansandNorway Austevoll Research Station StorebøNorway

The ballan wrasse(Labrus bergylta)is a marine fish belonging to the family Labridae characterized by 2 main morphotypes that occur in sympatry:spotty and *** studies have revealed differences in their life-history traits,such as growth and maturation;however,the genetic relationship between forms is presently *** 20 recently developed microsatellite markers,we conducted a genetic analysis of 41 and 48 spotty and plain ballan wrasse collected in Galicia(northwest Spain).The 2 morphotypes displayed highly significant genetic differences to each other(F_(ST)=0.018,Pk=*** this case,the frequency of spotty and plain morphotypes was significantly different(χ^(2)=9.46,P=0.002).It is concluded that there is significant genetic heterogeneity within this species,which appears to be highly associated with the spotty and plain forms,but not completely explained by *** the previously demonstrated biological differences between morphotypes,and the present genetic analyses,we speculate about the convenience of a taxonomic re-evaluation of this species.

关键词： ballan wrasse color morphotypes Labrus bergylta microsatellites speciation

根据承载聚合物绝缘子变形特性诊断其老化程度

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电瓷避雷器译丛 1995年第1期 10-15页

作者： k.,sv 邱子贤

Seismic isolation effect of lined circular tunnels with damping treatments

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Earthquake Engineering and Engineering Vibration 2008年第3期7卷 305-319页

作者： Seyyed M. Hasheminejad Amir k. Miri Acoustics Research Laboratory Department of Mechanical Engineering Iran University of Science and Technology Narmak Tehran 16844 Iran

The Havriliak-Negami model for dynamic viscoelastic material behavior and Biot＇s theory of poroelasticity are employed to develop an exact solution for three-dimensional scattering effect of harmonic plane P-sv waves from a circular cavity lined with a multilayered fluid-filled shell of infinite length containing viscoelastic damping materials and embedded within a fluid-saturated permeable surrounding soil medium. The analytical results are illustrated with numerical examples where the effects of liner/coating structural arrangement, viscoelastic material properties, liner-soil interface bonding condition, seismic excitation frequency, and angle of incidence on the induced dynamic stress concentrations are evaluated and discussed to obtain representative values of the parameters that characterize the system. It is demonstrated that incorporating viscoelastic damping materials with a low shear modulus in the constrained layer configuration is an efficient means of enhancing the overall seismic isolation performance, especially for near-normally incident seismic shear waves where the amplitudes of induced dynamic stresses may be reduced by up to one-third of those without isolation in a relatively wide frequency range. Some additional cases are considered and good agreements with solutions available in the literature are obtained.

关键词： underground tunnel permeable soil seismic wave scattering flee/constrained layer damping

Combined effects of Joule heating and nonuniform heat source/sink on unsteady MHD mixed convective flow over a vertical stretching surface embedded in a Darcy-Forchheimer porous medium

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Propulsion and Power Research 2022年第2期11卷 276-292页

作者： B.k.Sharma Rishu Gandhi Department of Mathematics Birla Institute of Technology and SciencePilani333031RajasthanIndia

This paper deals with an unsteady magnetohydrodynamics(MHD)heat and masstransfer for a viscous incompressible fluid through a vertical stretching surface embedded ina Darcy-Forchheimer porous medium in the presence of a non-uniform heat source/sink andfirst-order chemical *** porous surface is subjected to a uniform transverse *** influence of velocity,thermal,and concentration slip is also *** governing equations are coupled non-linear partial differential equations,which have been converted via similarity transformation into a set of ordinary differential *** resultantsystem of non-linear ordinary differential equations has been solved numerically with the helpof the“MATLAB”BVP4C *** are presented graphically to analyze the effects ofvarious physical parameters discovered in the problem such as Hartmann number(M),Forchheimer number(Fr),Grashof number(Gr),solutal Grashof number(Gc),suction parameter(S),porosity parameter(el),dimensionless velocity slip(sv),Prandtl number(Pr),dimensionless thermal slip(St),space-dependent heat source/sink parameter(eA1),temperature-dependent heat source/sink(eB)1),Eckert number(Ec),Schmidt number(Sc),chemical reaction parameter(g),unsteadiness parameter(A),and dimensionless concentration slip(Sc)on non-dimensionalvelocity ec0ðhÞ,temperature zðhÞ,and concentration efðhÞ*** influence of these parameters on skin-friction coefficient(C)f),Nusselt number(Nu)x),and Sherwood number(Sh)x)areexpressed in tabular *** is observed that an enhancement in Fr and el results in the declination of the velocity *** is an enhancement in temperature with an increment in theeA)1 and eB)*** physical representation of flow characteristics that appeared in the problem ispresented using various graphs to depict real-world applications in industrial and *** results were compared to previous studies,revealing that the two are in *** nov

关键词： Magnetohydrodynamics(MHD) Unsteady Heat and mass transfer Non-Darcian porous medium Heat source Joule effect

Flexural strength of fused filament fabricated (FFF) PLA parts on an open-source 3D printer

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Advances in Manufacturing 2018年第4期6卷 430-441页

作者： Shilpesh R. Rajpurohit Harshit k. Dave Department of Mechanical Engineering SV National Institute of Technology Surat Gujarat 395007 India

Fused filament fabrication (FFF) has been widely used to develop prototypes as well as functional parts owing to its capability for creating parts with complex geometries in a short time without the specific requirement of tooling. The mechanical properties of parts produced by FFF exhibit 70%-80% of the mechanical properties of parts produced by injection molding. The mechanical properties of FFF-produced parts are primarily dependent on the selection of various process variables. The mechanical properties of the part can be enhanced through the proper selection of process variables. In the present experimental investigation, the effects of the process variables, viz. raster angle, layer height, and raster width on the flexural properties of FFF-printed polylactic acid (PLA) is studied. The result shows that flexural strength is primarily influenced by layer height followed by raster angle. The sample printed with 100-μm layer height and 0° raster angle exhibits a higher tensile strength. Further, the microscopic examination of the deformed specimen is performed to understand the mode of failure. Specimens printed at different raster angles show different modes of failure.

关键词： Fused filament fabrication (FFF) Polylactic acid (PLA) Raster angle Layer height Raster width Flexural strength