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Patterns of grassland invasions by trees: insights from demographic and genetic spatial analyses

Journal of Plant Ecology 2015年第5期8卷 468-479页

作者： Martin Dovčiak Richard Hrivnák karol ujházy Dušan Gömöry State University of New York College of Environmental Science and Forestry(SUNY ESF)1 Forestry DriveSyracuseNY 13210USA Institute of Botany Slovak Academy of SciencesDúbravskácesta 9Bratislava 84523Slovakia Technical University in Zvolen Faculty of ForestryT.G.Masaryka 24Zvolen 96053Slovakia

Aims Woody invasions into grasslands have increased globally due to changing land use,climate and introduced woody species,but spatial processes generating and sustaining these invasions are not well *** gain insight into the patterns of spread of tree populations within grasslands,and to propose a full spatial analytical toolbox for studying native and non-native woody spe-cies spread when long-term data are not available,we tested if 50 years of grassland invasion in Western Carpathians by Norway spruce(Picea abies Karst.)proceeded by one of the two tradi-tionally competing hypotheses of species spread:(i)by frontier expansion,or(ii)by advanced groups established ahead of the population *** also tested whether the pattern of invasion changed over *** We analyzed the spatial demographic and genetic patterns of a Norway spruce population invading a Western Carpathian grass-land using ripley’s L(t)and genetic kinship coefficients(Fij).We mapped and genotyped spruce trees across the invasion front(from the invasion leading edge to fully colonized grassland near the source population)using three demographic classes(adults,juve-niles and seedlings)to approximate the temporal aspects of the *** studied how the spatial patterns of invasion by indi-vidual demographic classes and their genetic kinship varied among adjacent plots established at different distances from the source population(ranging from 0 to 160 m,in 40-m distance increments).Important Findings Juveniles were positively genetically related to adults on fine scales(<4 m),suggesting that adults within the grassland acted as a seed source and accelerated early ***,adults did not act as nucleation centers for the formation of advanced juvenile ***,geneti-cally unrelated juveniles formed groups independently of *** groups were small and separate at the leading edge but they increased in size and graded into a continuous zone near the source popul

关键词： genetic spatial structure mountain meadows point pattern analysis population structure secondary succession

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Mathematical Modelling of the Transient Response of Pipeline

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Journal of Thermal Science 2016年第6期25卷 549-557页

作者： Dawid Taler karol Kaczmarski Cracow University of Technology Faculty of Environmental Engineering Cracow University of Technology Faculty of Mechanical Engineering

Steam pipelines applied in power units operate at high pressures and *** addition,to stress from the pipeline pressure also arise high thermal stresses in transient states such as start-up,shutdown or a load change of the power ***-varying stresses are often the cause of the occurrence of fatigue cracks since the plastic deformations appear at the stress concentration *** determine the transient temperature of the steam along the steam flow path and axisymmetric temperature distribution in the pipeline wall,a numerical model of pipeline heating was *** determine the transient temperature of the steam and pipeline wall the finite volume method(FVM) was used Writing the energy conservation equations for control areas around all the nodes gives a system of ordinary differential equations with respect to *** system of ordinary differential equations of the first order was solved by the Runge-Kutta method of the fourth order to give the time-temperature changes at the nodes lying in the area of the wall and *** steam pressure distribution along pipeline was determined from the solution of the momentum conservation *** on the calculated temperature distribution,thermal stresses were *** friction factor was calculated using the correlations of Churchill and Haaland,which were proposed for pipes with a rough inner *** assess the accuracy of the proposed model,numerical calculations were also performed for the thin-walled pipe,and the results were compared to the exact analytical *** of the results shows that the accuracy of the proposed model of pipeline heating is very *** paper presents examples of the determination of the transient temperature of the steam and the wall.

关键词： pipeline steam heating walled satisfactory Pipeline conservation lying Kutta Runge

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Influence of Biomass Co-combustion on Heating Surfaces Thermal Efficiency

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Journal of Thermal Science 2018年第5期27卷 427-432页

作者： GRADZIEL Slawomir WITKOWSKI karol Institute of Thermal Power Engineering Cracow University of Technology31-864 Kraków Poland European Institute for Energy Research 76131 Karlsruhe Germany

Pulverized coal-fired(PCF) boilers were first and foremost intended to fire pulverized hard or brown coal. However, biomass co-firing has become a fairly common practice in the Polish power generation system and many existing boilers have been modernized to serve this purpose. This paper presents calculations of the coefficient of thermal efficiency of the boiler heating surfaces and of the time needed for complete reconstruction of deposits on the second-stage steam reheater(RHII) of an OP-380 boiler with the output of 380×10~3 kg/h. The boiler was equipped with a purpose-designed installation of direct feeding of biomass. The main co-fired fuels were wood and sunflower husk pellets. Intense formation of deposits on the steam reheater tubes and problems related to a reduction in the diameters of the tubes were identified during the power unit operation.

关键词： biomass co-combustion ash deposit coefficient of thermal efficiency

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Time-course monitoring of in vitro biotransformation reaction via solid-phase microextraction-ambient mass spectrometry approaches

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Journal of Pharmaceutical Analysis 2022年第1期12卷 186-191页

作者： karol Jaroch Janusz Pawliszyn Department of Chemistry University of WaterlooWaterlooN2L 3G1Canada Department of Pharmacodynamics and Molecular Pharmacology Faculty of PharmacyCollegium Medicum in BydgoszczNicolaus Copernicus University in Toruń Poland85090BydgoszczPoland

The solid-phase microextraction technique quantifies analytes without considerably affecting the sample ***,a proof-of-concept study was conducted to demonstrate the use of coated probe electrospray ionization(coated-PESI)and coated blade spray(CBS)as ambient mass spectrometry approaches for monitoring drug *** ability of these methods was investigated for monitoring the dephosphorylation of a prodrug,combretastatin A4 phosphate(CA4P),into its active form,combretastatin A4(CA4),in a cell culture medium supplemented with fetal bovine *** CBS spot analysis was modified to achieve the same extraction efficiency as protein precipitation and obtained results in 7 *** coated-PESI performs extraction without consuming any samples,it is the preferred technique in the case of a limited sample *** coated-PESI only extracts small quantities of analytes,it uses the desorption solvent volume of 5-10 pL,resulting in high sensitivity,thus allowing the detection of compounds after only 1 min of *** biotransformation of CA4P into CA4 via phosphatases occurs within the simple matrix,and the proposed sample preparation techniques are suitable for monitoring the biotransformation.

关键词： Solid-phase microextraction Coated probe electrospray ionization Coated blade spray Combretastatin Biotransformation Prodrug activation

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Uniformity of Direct Unions of Chord

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 225-234页

作者： Rafa Kapelko karol Marchwicki Department of Computer Science Faculty of Fundamental Problems of Technology Wrocaw University of Technology

In this article we investigate the uniformity of direct union of k copies of Chord which is an improvedversion of Chord P2P system. We are interested in the maximal and the minimal areas controlled by nodes inthe system. We recall that the function n→k/k!.n-（1＋1/k）is a lower threshold and that the function n→1/n In（nlnk-k（n（k-1）1）/（k-1）1is an upper threshold for sizes of areas controlled by nodes in the direct union of kcopies of Chord.

关键词： peer-to-peer network modification of chord threshold asymptotic order statistic

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Conditional Probability on the Kpka's D-posets

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2197-2204页

作者： karol SAMUELCÍK Ivana HOLLÁ Department of Mathematics Faculty of Natural SciencesMatej Bel University

Kopka＇s D-poset is a very important notion in quantum structures. In this paper the conditional probability on the Kopka＇s D-posets is studied. The notion of conditional probability is introduced and the basic prope... 详细信息

关键词： Kopka's D-posers conditional probability on the Kopka's D-posers

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Solid-phase microextraction of endogenous metabolites from intact tissue validated using a Biocrates standard reference method kit

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Journal of Pharmaceutical Analysis 2023年第1期13卷 55-62页

作者： Runshan Will Jiang karol Jaroch Janusz Pawliszyn Department of Chemistry University of WaterlooWaterlooN2L 3G1Canada Department of Pharmacodynamics and Molecular Pharmacology Faculty of PharmacyCollegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszcz85-089Poland

Improved analytical methods for the metabolomic profiling of tissue samples are constantly ***,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the endogenous *** this study,solid-phase microextraction(SPME)fibers were used to monitor changes in endogenous compounds in homogenized and intact ovine lung *** SPME,a Biocrates AbsoluteIDQ assay was applied to make a downstream targeted metabolomics analysis and confirm the advantages of in vivo SPME *** AbsoluteIDQ kit enabled the targeted analysis of over 100 metabolites via solid-liquid extraction and *** analysis revealed significant differences between conventional liquid extractions from homogenized tissue and SPME results for both homogenized and intact tissue *** addition,principal component analysis revealed separated clustering among all the three sample groups,indicating changes in the metabolome due to tissue homogenization and the chosen sample preparation ***,clear differences in free metabolites were observed when extractions were performed on the intact and homogenized tissue using identical SPME ***,a direct comparison showed that 47 statistically distinct metabolites were detected between the homogenized and intact lung tissue samples(P<0.05)using mixed-mode SPME *** changes were probably due to the disruptive homogenization of the *** study's findings highlight both the importance of sample preparation in tissue-based metabolomics studies and SPME's unique ability to perform minimally invasive extractions without tissue biopsy or homogenization while providing broad metabolite coverage.

关键词： Solid-phase microextraction Solvent extraction Metabolomics Sample preparation In vivo sampling

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The development of the Rook's(Corvus frugilegus)colony in the face of shifting spring phenology

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Avian Research 2022年第2期13卷 170-174页

作者： Adam Zbyryt karol Zub Cezary Mitrus Doctoral School of Exact and Natural Sciences University of Bialystok Mammal Research Institute Polish Academy of Sciences Department of Vertebrate Ecology and Paleontology Institute of BiologyWroclaw University of Environmental and Life Sciences

Many birds species breed in *** of the species in the Corvidae family nesting in groups is the Rook(Corvus frugilegus).The construction of the nest is costly for birds and needs high energy ***,birds should optimize the time of nest building in relation to environmental,especially weather,***,birds should adapt their breeding phenology,including the date of starting the construction of nests for climate *** observed the dynamics of increasing numbers of nests in a colony of Rooks in relation to air temperature,wind,rainfall,snowfall and day-length(indirect indicator of photoperiodism).Observations were carried out during three breeding seasons(2015-2017)in a large rookery in a big city in north-eastern *** increase in the number of nests was correlated only with day length and no effect of climatic factors on the number of nests in the colony was *** of nests varied significantly between successive years of *** the case of the Rook(predictable breeders),the photoperiod seems to be the most important factor influencing breeding behavior,especially nest *** the last three decades,increasing temperature and time of spring phases have advanced and have influenced changes in the phenology of the availability of food ***,a rapid decline in the numbers of breeding pairs of the Rook in Poland has been observed,especially in the last three *** attachment to the length of the day,which is the main factor responsible for the development of the breeding colony,makes the Rook appear to be a species with low plasticity in the face of rapid climate ***,we suggest that may indirectly influence the decrease in the breeding population of the Rook.

关键词： Breeding colony Climate change Corvus frugilegus Nest building Photoperiodism Predictable breeding

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Determination of coefficients of friction for laminated veneer lumber on steel under high pressure loads

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Friction 2021年第2期9卷 367-379页

作者： Michael DORN karolína HABROVÁ Radek KOUBEK Erik SERRANO Department of Building Technology Linnaeus UniversityVäxjö35252Sweden Czech University of Life Sciences Prague-Department of Materials and Engineering Technology Prague 16521Czech Republic Daikin UK The HeightsBrooklandsWeybridgeKT130NYUnited Kingdom Division of Structural Mechanics Lund UniversityLund 22100Sweden

In this study,static coefficients of friction for laminated veneer lumber on steel surfaces were determined *** focus was on the frictional behaviors at different pressure levels,which were studied in combination with other influencing parameters:fiber orientation,moisture content,and surface *** of friction were obtained as 0.10–0.30 for a smooth steel surface and as high as 0.80 for a rough steel *** influenced the measured coefficients of friction,and lower normal pressures yielded higher *** influence of fiber angle was observed to be moderate,although clearly detectable,thereby resulting in a higher coefficient of friction when sliding perpendicular rather than parallel to the *** specimens contained higher coefficients of friction than oven-dry *** results provide realistic values for practical applications,particularly for use as input parameters of numerical simulations where the role of friction is often wrongfully considered.

关键词： laminated veneer lumber(LVL) wood static friction high pressure angle-to-grain moisture content

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Modeling of Flow System Dynamics

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Journal of Thermal Science 2004年第1期13卷 56-61页

作者： Andrzej Miller Krzysztof Badyda Jaroslaw Dyjas karol Miller Institute of Heat Engineering Warsaw University of TechnologyNowowiejska 2500-665WarsawPolandInstitute of Heat EngineeringWarsaw University of TechnologyNowowiejska 2500-665WarsawPolandInstitute of Heat EngineeringWarsaw University of TechnologyNowowiejska 2500-665WarsawPolandSchool of Mechanical Engineering University of Western Australia35 Stirling HighwayCrawley WA 6009Australia

This paper presents non-linear and linear models of flow system of laboratory stand (semi-industrial scale) with pressurized fluidized bed boiler. The non-linear model belongs to the class of lumped parameter models. The linear model was obtained experimentally using a novel method for design of control systems in industrial plants - MIKOZ. This study has connection with comparison of various methods of mathematical modeling of flow systems frequently encountered in power equipment.

关键词： flow system modeling lumped parameter model frequency domain identification.

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