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Intraspecific trait variation in three common grass species reveals fine-scale species adjustment to local environmental conditions

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Journal of Plant Ecology 2018年第6期11卷 887-898页

作者： Tina Buchmann jens Schumacher Christiane roscher UFZ Helmholtz Centre for Environmental ResearchTheodor-Lieser-Strasse 4Halle 06120Germany Institute of Mathematics StochasticsFriedrich Schiller University JenaErnst-Abbe-Platz 2Jena 07743Germany UFZ Helmholtz Centre for Environmental ResearchPhysiological DiversityPermoserstraße 15Leipzig 04318Germany German Centre for Integrative Biodiversity research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5eLeipzig 04103Germany

Aims Studies along environmental gradients have shown that intraspecific trait variation(ITV)may contribute considerably to community-level trait ***,we lack knowledge about how the extent of ITV varies on a local scale and whether a varying extent of ITV is related to differences in local environmental site and plant commu-nity *** We investigated plant height,specific leaf area(SLA),leaf dry mat-ter content(LDMC)and leaf greenness of three common grass spe-cies(Arrhenatherum elatius,Dactylis glomerata,Poa pratensis)in 12 mown grasslands in a local study area around Jena(Thuringia,Germany)across three spatially hierarchical sampling levels:between sites,between subplots within site and within *** Findings Arrhenatherum elatius and *** had higher means in plant height and a lower variation in leaf traits than *** major proportions of variation in leaf traits of *** and *** were found within subplots,while the traits of *** varied mainly between *** correlations across the hierarchical sam-pling levels were highly consistent in ***,but more variable in *** and *** site and plant commu-nity characteristics mostly explained a larger proportion of variation in trait means in *** than in *** and ***,while metrics of ITV were generally less *** results suggest that trait variation in *** and *** is more strongly related to within-site conditions(*** interactions),while differences in local environmental conditions between sites have a strong impact on trait variation in *** our study was limited to three grass species,further studies with a greater number of species are required to make generalizations about the importance of biotic interactions and environmental conditions as drivers of ITV at local scale.

关键词： grass species intraspecific trait variation leaf traits

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A concurrent optimization approach for energy efficient multiple axis positioning tasks

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Journal of Control and Decision 2016年第4期3卷 223-247页

作者： Christian Hansen jens Kotlarski Tobias Ortmaier Institute of Mechatronic Systems Leibniz Universitat HannoverHanoverGermany

Automated production systems typically comprise numerous electrical servo drives,many of which conduct positioning motions,*** handling or manipulation *** power electronics of modern multi-axis systems often comprise coupled DC-links,enabling for internal exchange of recuperative brake ***,the motion sequences of manipulators are often commanded at maximum dynamics for minimum time motion,neglecting possible optimization potential,*** idle time,leading to inefficient energy management.A robust trajectory optimization approach based on the particle swarm algorithm and well-established path planning methods is presented for the adaption of multi-axis positioning tasks with only two parameters per axis and positioning motion during system *** results prove that,depending on the positioning task and chosen optimization constraints,energy demands are distinctly *** approach is applicable to diverse multi-axis configurations and enables for considerable energy savings without additional hardware invest.

关键词： Multiple axis systems electrical servo drive energy efficient control trajectory optimization positioning tasks

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Ethyl-iophenoxic acid as a quantitative bait marker for small mammals

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Integrative Zoology 2022年第6期17卷 981-990页

作者： Kyra JACOBLINNErT Christian IMHOLT Detlef SCHENKE jens JACOB Julius Kühn Institute(JKI) Federal Research Centre for Cultivated PlantsInstitute for Plant Protection in Horticulture and ForestsVertebrate ResearchMünsterGermany Department of Behavioral Biology University of OsnabrückOsnabrückGermany Julius Kühn Institute(JKI) Federal Research Centre for Cultivated PlantsInstitute for Ecological ChemistryPlant Analysis and Stored Product ProtectionBerlinGermany

Bait markers are indispensable for ecological research but in small mammals,most markers are invasive,expensive and do not enable quantitative analyses of ***-iophenoxic acid(Et-IPA)is a non-toxic,quantitative bait marker,which has been used for studying bait uptake in several carnivores and *** developed a bait with Et-IPA,assessed its palatability to common voles(Microtus arvalis),and determined the dose-residue-relation for this important agricultural pest rodent ***-IPA concentrations of 40 to 1280μg Et-IPA per g bait were applied to wheat using sunﬂower oil or polyethylene glycol 300 as potential *** a laboratory study,common voles were offered the bait and blood samples were collected 1,7,and 14 days after *** samples were analyzed with LC-ESI-MS/MS for blood residues of ***ﬂower-oil was the most suitable bait ***-IPA seemed to be palatable to common voles at all test ***-dependent residues could be detected in blood samples in a dose-dependent manner and up to 14 days after uptake enabling generation of a calibration curve of the dose-residue ***-IPA was present in common vole blood for at least 14 days,but there was dissipation by 33–37%depending on ***-IPA meets many criteria for an“ideal”quantitative bait marker for use in futureﬁeld studies on common voles and possibly other small mammal species.

关键词： baiting biomarker Microtus arvalis quantitative bait marker small mammals

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Hard-thermal-loop QED thermodynamics

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Chinese Physics C 2010年第9期34卷 1527-1529页

作者：苏楠 jens O.Andersen Michael Strickland frankfurt Institute for Advanced Studies Department of Physics Norwegian University of Science and Technology Department of Physics Gettysburg College

The weak-coupling expansion for thermodynamic quantities in thermal field theories is poorly convergent unless the coupling constant is *** discuss the calculation of the free energy for a hot gas of electrons and photons to three-loop order using hard-thermal-loop perturbation theory （HTLpt）.We show that the hard-thermal-loop perturbation reorganization improves the convergence of the successive approximations to the QED free energy at large coupling,e ～ *** reorganization is gauge invariant by construction,and due to the cancellations among various contributions,we obtain a completely analytic result for the resummed thermodynamic potential at three loops.

关键词： resummation hard-thermal-loop thermal field theory QED free Energy

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New design paradigm for heterogeneous catalysts

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National Science review 2015年第2期2卷 140-143页

作者： Aleksandra Vojvodic jens K.N?rskov SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory Department of Chemical Engineering Stanford University

Both scientiic discovery and technological development are at some point faced with the question of how to progress from a trial-and-error approach to a highly controlled design *** heterogeneous catalysis,the search for the optimal active site of a catalyst for a given chemical reaction has been the central objective of research for almost a ***

关键词： New design paradigm for heterogeneous catalysts

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An analytical validation for the attenuation of lateral propagating light in sea ice

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Acta Oceanologica Sinica 2015年第3期34卷 1-8页

作者： ZHAO Jinping LI Tao EHN jens BArBEr David Physical Oceanography Laboratory Ocean University of China Centre for Earth Observation Science University of Manitoba

The attenuation of lateral propagating light （LPL） in sea ice was measured using an artificial light source in the Canadian Arctic during the 2007/2008 winter. The apparent attenuation coefficientμ（λ）for lateral prop-agating light was obtained from the measured logarithmic relative variation rate. In this study an analytical solution based on the strict optical theories is developed to validate the measured result. There is a good consistency between theoretical solution and measured data, by which a quite simple but very rigorous relationship among the light source, measurement geometry, and measured irradiance is established. The attenuation coefficients acquired by measurement and theory are the diffusion attenuation as an apparent optical property of ice, independent of the light source and shining condition. The attenuation ability of sea ice should be caused by the microstructure of sea ice, such as crystal size, ice density, brine volume, air inclusion, etc. It also includes the leak from both interfaces by directional scattering. It is verified that the measuring approach is operational and accurate to measure the attenuation of the LPL. The solution from this study did not tell the connection among the extinction and the inclusions of sea ice theoretically be-cause of insufficient understanding.

关键词： Arctic,sea ice lateral propagating light optical attenuation coefficient artificial light analytical solution

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Investigation of Load Prediction on the Mexico rotor Using the Technique of Determination of the Angle of Attack

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 506-514页

作者： YANG Hua SHEN Wenzhong SOrENSEN jens Nork er ZHU Weijun College of Power and Energy Engineering Yangzhou UniversityYangzhou 225009China Department of Mechanical Engineering Technical University of Denmark2800 LyngbyDenmark

Blade element moment（BEM） is a widely used technique for prediction of wind turbine aerodynamics performance,the reliability of airfoil data is an important factor to improve the prediction accuracy of aerodynamic loads and power using a BEM *** method of determination of angle of attack on rotor blades developed by SHEN,et al is successfully used to extract airfoil data from experimental characteristics on the MEXICO（Model experiments in controlled conditions） *** surface pressure and particle image velocimetry（PIV） flow fields at different rotor azimuth positions are examined to determine the sectional airfoil *** present technique uses simultaneously both PIV data and blade pressure data that include the actual flow conditions（for example,tunnel effects）,therefore it is more advantageous than other techniques which only use the blade loading（pressure data）.The extracted airfoil data are put into a BEM code,and the calculated axial and tangential forces are compared to both computations using BEM with Glauert＇s and SHEN＇s tip loss correction models and experimental *** comparisons show that the present method of determination of angle of attack is correct,and the re-calculated forces have good agreements with the experiment.

关键词： wind turbine rotor aerodynamics airfoil data

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Development of high damage threshold laser-machined apodizers and gain filters for laser applications

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High Power Laser Science and Engineering 2016年第3期4卷 113-119页

作者： Patrick rambo jens Schwarz Mark Kimmel John L.Porter Sandia National Laboratories

We have developed high damage threshold filters to modify the spatial profile of a high energy laser beam. The filters are formed by laser ablation of a transmissive window. The ablation sites constitute scattering centers which can be filtered in a subsequent spatial filter. By creating the filters in dielectric materials, we see an increased laser-induced damage threshold from previous filters created using ‘metal on glass' lithography.

关键词： apodization laser beam shaping laser micro-machining spatial filtering

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Integrating water use systems and soil and water conservation measures into a hydrological model of an Iranian Wadi system

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Journal of Arid Land 2020年第4期12卷 545-560页

作者： Nariman MAHMOODI jens KIESEL Paul D WAGNEr Nicola FOHrEr Department of Hydrology and Water resources Management Institute for Natural Resource ConservationKiel UniversityKiel 24118Germany Department of Ecosystem research Leibniz-Institute of Freshwater Ecology and Inland Fisheries(IGB)Berlin 12489Germany

Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures(SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool(SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs(Default model) with a model setup with WUSs and SWCMs(WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(rSr)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly.

关键词： SWAT model stream flow Wadis multi-metric framework water use systems soil and water conservation measures Halilrood Basin

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Electrochemical measurement of serotonin by Au-CNT electrodes fabricated on microporous cell culture membranes

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Microsystems & Nanoengineering 2020年第1期6卷 494-506页

作者： Ashley A.Chapin Pradeep r.rajasekaran David N.Quan Liangbing Hu jens Herberholz William E.Bentley reza Ghodssi Fischell Department of Bioengineering College ParkMD 20742USA Institute for Systems research College ParkMD 20740USA Department of Materials Science and Engineering College ParkMD 20740USA Department of Psychology and Neuroscience and Cognitive Science Program College ParkMD 20740USA Institute for Bioscience and Biotechnology research RockvilleMD 20850USA robert E.Fischell Institute for Biomedical Devices RockvilleMD 20850USA Department of Electrical and Computer Engineering College ParkMD 20742USA

Gut–brain axis(GBA)communication relies on serotonin(5-HT)signaling between the gut epithelium and the peripheral nervous system,where 5-HT release patterns from the basolateral(i.e.,bottom)side of the epithelium activate nerve *** have been few quantitative studies of this gut-neuron signaling due to a lack of real-time measurement tools that can access the basolateral gut *** vitro platforms allow quantitative studies of cultured gut tissue,but they mainly employ offline and endpoint assays that cannot resolve dynamic molecular-release ***,we present the modification of a microporous cell culture membrane with carbon nanotube-coated gold(Au-CNT)electrodes capable of continuous,label-free,and direct detection of 5-HT at physiological *** characterization of single-walled carbon nanotube(SWCNT)-coated Au electrodes shows increased electroactive surface area,5-HT specificity,sensitivity,and saturation time,which are correlated with the CNT film drop-cast *** microliters of CNT films,with a 10-min saturation time,0.6μA/μM 5-HT sensitivity,and reliable detection within a linear range of 500 nM–10μM 5-HT,can be targeted for high-concentration,high-time-resolution 5-HT *** films(12.5μL)with a 2-h saturation time,4.5μA/μM 5-HT sensitivity,and quantitative detection in the linear range of 100 nM–1μM can target low concentrations with low time *** electrodes achieved continuous detection of dynamic diffusion across the porous membrane,mimicking basolateral 5-HT release from cells,and detection of cell-released 5-HT from separately cultured rIN14B cell ***-integrated cell culture systems such as this can improve in vitro molecular detection mechanisms and aid in quantitative GBA signaling studies.

关键词： release saturation dynamic

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