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Lipid concentration and composition in xylem sap of woody angiosperms from a tropical savanna and a seasonal rainforest

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Plant Diversity 2024年第1期46卷 126-133页

作者： Ling-Bo Huang Xinyi Guan Amy Ny Aina Aritsara Jun-Jie Zhu Steven Jansen Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources Guangxi Key Laboratory of Forest Ecology and ConservationGuangxi UniversityDaxuedong Road 100NanningGuangxi 530004China Institute of Botany Ulm UniversityAlbert-Einstein-Allee 11Ulm89081Germany

Lipids may play an important role in preventing gas embolisms by coating nanobubbles in xylem *** studies on xylem sap lipids have been reported for temperate plants,and it remain unclear whether sap lipids have adaptational significance in tropical *** this study,we quantify the lipid composition of xylem sap for angiosperm species from a tropical savanna(seven species)and a seasonal rainforest(five species)using mass *** found that all twelve species studied contained lipids in their xylem sap,including galactolipids,phospholipids and triacylglycerol,with a total lipid concentration ranging from 0.09 to 0.26 nmol/*** was no difference in lipid concentration or composition between plants from the two sites,and the lipid concentration was negatively related to species’open vessel ***,savanna species showed little variation in lipid composition between the dry and the rainy *** results support the hypothesis that xylem sap lipids are derived from the cytoplasm of individual conduit cells,remain trapped inside individual conduits,and undergo few changes in composition over consecutive seasons.A xylem sap lipidomic data set,which includes 12 tropical tree species from this study and 11 temperate tree species from literature,revealed no phylogenetic signals in lipid composition for these *** study fills a knowledge gap in the lipid content of xylem sap in tropical trees and provides additional support for their common distribution in xylem sap of woody *** appears that xylem sap lipids have no adaptive significance.

关键词： Xylem sap Lipids Tropical savanna Tropical rainforest Vessels

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Studies on Differential Nuclear Translocation Mechanism and Assembly of the Three Subunits of the Arabidopsis thaliana Transcription Factor NF-Y

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Molecular Plant 2012年第4期5卷 876-888页

作者： Dieter Hackenberg Yanfang Wu Andrea Voigt Robert Adams Peter Schramm Bernhard GrimmI Institute of Biology/Plant Physiology Humboldt University Philippstr. 13 Building 12 10115 Berlin Germany

The eukaryotic transcription factor NF-Y consists of three subunits （A, B, and C）, which are encoded in Ara- bidopsis thaliana in multigene families consisting of 10, 13, and 13 genes, respectively. In principle, all potential combi- nations of the subunits are possible for the assembly of the heterotrimeric complex. We aimed at assessing the probability of each subunit to participate in the assembly of NF-Y. The evaluation of physical interactions among all members of the NF-Y subunit families indicate a strong requirement for NF-YB/NF-YC heterodimerization before the entire complex can be accomplished. By means of a modified yeast two-hybrid system assembly of all three subunits to a heterotrimeric complex was demonstrated. Using GFP fusion constructs, NF-YA and NF-YC localization in the nucleus was demonstrated, while NF- YB is solely imported into the nucleus as a NF-YC-associated heterodimer NF-YC. This piggyback transport of the two Arabidopsis subunits differs from the import of the NF-Y heterotrimer of heterotrophic organisms. Based on a peptide structure model of the histone-fold-motifs, disulfide bonding among intramolecular conserved cysteine residues of NF-YB, which is responsible for the redox-regulated assembly of NF-YB and NF-YC in human and Aspergillus nidulans, can be excluded for Arabidopsis NF-YB.

关键词： gene expression transcriptional control and transcription factors nuclear translocation protein-proteininteraction.

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Periodic interstellar scintillation variations of PSRs J0613-0200 and J0636+5128 associated with the Local Bubble shell

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中国科学:物理学、力学、天文学英文版 2023年第11期66卷 221-232页

作者： Yulan Liu Robert A.Main Joris P.W.Verbiest Ziwei Wu Krishnakumar M.Ambalappat Jiguang Lu David J.Champion Ismael Cognard Lucas Guillemot Kuo Liu James W.Mc Kee Nataliya Porayko Golam.M.Shaifullah Gilles Theureau National Astronomical Observatories Chinese Academy of SciencesBeijing100101China Fakultät für Physik Universität BielefeldBielefeld33501Germany Max-Planck-Institut für Radioastronomie Bonn53121Germany Florida Space Institute University of Central FloridaOrlandoFL32826USA Station de radioastronomie de Nançay Observatoire de ParisNançay18330France Laboratoire de Physique et Chimie de l’Environnement et de l’Espace Universitéd’OrléansOrléans45071France E.A.Milne Centre for Astrophysics University of HullHullHU67RXUK Centre of Excellence for Data Science Artificial Intelligence and ModellingUniversity of HullHullHU67RXUK Dipartimento di Fisica“G.Occhialini” Universitàdi Milano-BicoccaMilano20126Italy INAF-Osservatorio Astronomico di Cagliari Selargius(CA)09047Italy INFN Sezione di Milano-BicoccaMilano20126Italy

Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar *** a pulsar is in a binary system,then investigating the orbital parameters is possible through analysis of the orbital variation of *** observations carried out from 2011 to 2020 by the European Pulsar Timing Array radio telescopes,PSRs J0613-0200and J0636+5128 show strong annual variations in their scintillation velocity,while the former additionally exhibits an orbital *** theory and Markov-chain-Monte-Carlo methods are used to interpret these periodic *** assume a thin and anisotropic scattering screen model,and discuss the mildly and extremely anisotropic scattering *** J0613-0200is best described by mildly anisotropic scattering,while PSR J0636+5128 exhibits extremely anisotropic *** measure the distance,velocity,and degree of anisotropy of the scattering screen for our two pulsars,finding that scattering screen distances from Earth for PSRs J0613-0200 and J0636+5128 are 316_(-20)^(+28)pc and 262_(-38)^(+96)pc,*** positions of these scattering screens are coincident with the shell of the Local Bubble towards both *** associations add to the growing evidence of the Local Bubble shell as a dominant region of scattering along many sightlines.

关键词： pulsar interstellar scintillation ionized interstellar medium

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STABILIZATION, REFORMATION AND MELTING OF POLY(L-LACTIDE) CRYSTALLITES

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Chinese Journal of Polymer Science 2007年第1期25卷 83-94页

作者： Tai-Yon Cho Barbara Heck Gert Strobl Physikalisches Institut Albert-Ludwigs-Universitt Freiburg 79104 FreiburgGermany

The large size of the crystallites in poly（L-lactide） and the low growth rate enable detailed time- and temperaturedependent X-ray scattering studies of the ordering processes to be carded out. A layer located intermediate between crystals and melt-like regions is observed which finally takes on crystalline order. Recrystallization processes during heating change the complete stack structure rather than the crystallites individually and produce voids in the stacks, Establishment of a new stable structure after a temperature jump in the melting range can be followed in time. DSC experiments indicate times of melting of the order of minutes.

关键词： Poly(L-lactide) Polymer crystallization Small angle X-ray scattering Semicrystalline structure.

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Trajectory analysis at intersections for traffic rule identification

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Geo-Spatial Information Science 2021年第1期24卷 75-84,I0010页

作者： Chenxi Wang Stefania Zourlidou Jens Golze Monika Sester Institute of Cartography and Geoinformatics Leibniz University HannoverHannoverGermany

In this paper,we focus on trajectories at intersections regulated by various regulation types such as traffic lights,priority/yield signs,and right-of-way *** test some methods to detect and recognize movement patterns from GPS trajectories,in terms of their geometrical and spatio-temporal *** particular,we first find out the main paths that vehicles follow at such *** then investigate the way that vehicles follow these geometric paths(how do they move along them).For these scopes,machine learning methods are used and the performance of some known methods for trajectory similarity measurement(DTW,Hausdorff,and Fréchet distance)and clustering(Affinity propagation and Agglomerative clustering)are compared based on clustering ***,the movement behavior observed at six different intersections is analyzed by identifying certain movement patterns in the speed-and time-profiles of *** show that depending on the regulation type,different movement patterns are observed at *** finding can be useful for intersection categorization according to traffic *** practicality of automatically identifying traffic rules from GPS tracks is the enrichment of modern maps with additional navigation-related information(traffic signs,traffic lights,etc.).

关键词： Traffic rules traffic regulators GPS trajectories intersection classification speed-profiles clustering similarity measures

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Combining rhizosphere and soil-based P management decreases the P fertilizer demand of China by more than half based on LePA model simulations

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Journal of Integrative Agriculture 2023年第8期22卷 2509-2520页

作者： YU Wen-jia LI Hai-gang Peteh MNKEBIWE YANG Xue-yun GUO Da-yong LI Cui-lan ZHU Yi-yong XIAO Jing-xiu LI Guo-hua SUN Zhi Torsten MüLLER SHEN Jian-bo Key Laboratory of Plant–Soil Interactions College of Resources and Environmental Sciences/National Academy of Agriculture Green Development of Ministry of EducationChina Agricultural UniversityBeijing 100193P.R.China Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources/Key Laboratory of Agricultural Ecological Security and Green Development at Universities of Inner Mongolia Autonomous Region Inner Mongolia Agricultural UniversityHohhot 010018P.R.China Department of Fertilization and Soil Matter Dynamics Institute of Crop ScienceUniversity of HohenheimStuttgart 70593Germany Key Laboratory of Plant Nutrition and the Agri-Environment in Northwest China College of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712199P.R.China College of Agronomy Henan University of Science and TechnologyLuoyang 471000P.R.China Department of Agricultural Resources and Environment College of Resources and EnvironmentJilin Agricultural UniversityChangchun 130118P.R.China Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095P.R.China College of Resources and Environment Yunnan Agricultural UniversityKunming 650500P.R.China Plant Production Systems Group Wageningen UniversityWageningen 6700Netherlands Israel Chemicals Ltd.(ICL) Tel Aviv 61070Israel

Phosphorus(P)is a finite natural resource and is increasingly considered to be a challenge for global *** in China plays a key role in global sustainable P *** and soil-based P management are necessary for improving P-use efficiency and crop productivity in intensive agriculture in China.A previous study has shown that the future demand for phosphate fertilizer by China estimated by the LePA model(legacy phosphorus assessment model)can be greatly reduced by soil-based P management(the building-up and maintenance approach).The present study used the LePA model to predict the phosphate demand by China through combined rhizosphere and soil-based P management at county scale under four P fertilizer scenarios:(1)same P application rate as in 2012;(2)rate maintained same as 2012 in low-P counties or no P fertilizer applied in high-P counties until targeted soil Olsen-P(TPOlsen)level is reached,and then rate was the same as P-removed at harvest;(3)rate in each county decreased to1–7 kg ha^(-1) yr^(-1) after TPOlsen is reached in low-P counties,then increased by 0.1–9 kg ha^(-1) yr^(-1) until equal to P-removal;(4)rate maintained same as 2012 in low-P counties until TPOlsen is reached and then equaled to P-removal,while the rate in high-P counties is decreased to 1–7 kg ha^(-1) yr^(-1) until TPOlsen is reached and then increased by 0.1–9 kg ha^(-1) yr^(-1)until equal to *** predictions showed that the total demand for P fertilizer by whole China was 693 Mt P2O5and according to scenario 4,P fertilizer could be reduced by 57.5%compared with farmer current practice,during the period 2013–*** model showed that rhizosphere P management led to a further 8.0%decrease in P fertilizer use compared with soil-based P *** average soil Olsen-P level in China only needs to be maintained at 17 mg kg^(-1) to achieve high crop *** results provide a firm basis for government to issue-relevant policies for sustainable

关键词： phosphorus reserves Pmanagement crop agriculture China modelling

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Modeling and simulation of microstructure in metallic systems based on multi-physics approaches

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npj Computational Materials 2022年第1期8卷 867-881页

作者： Jaber Rezaei Mianroodi Pratheek Shanthraj Chuanlai Liu Samad Vakili Sharan Roongta Nima Hamidi Siboni Nathan Perchikov Yang Bai Bob Svendsen Franz Roters Dierk Raabe Martin Diehl Microstructure Physics and Alloy Design Max-Planck-Institut für Eisenforschung40237DüsseldorfGermany Ergodic Labs Lohmühlenstraße12435BerlinGermany The Department of Materials The University of ManchesterManchesterM139PLUK Material Mechanics RWTH Aachen University52062AachenGermany Department of Computer Science KU LeuvenCelestijnenlaan 200A3001LeuvenBelgium Department of Materials Engineering KU LeuvenKasteelpark Arenberg 443001LeuvenBelgium

The complex interplay between chemistry,microstructure,and behavior of many engineering materials has been investigated predominantly by experimental *** to the increase in computer power,advances in computational modeling methods have resulted in a level of sophistication which is comparable to that of *** the continuum level,one class of such models is based on continuum thermodynamics,phase-field methods,and crystal plasticity,facilitating the account of multiple physical mechanisms (multi-physics) and their interaction during microstructure *** paper reviews the status of simulation approaches and software packages in this field and gives an outlook towards promising research directions.

关键词： computer microstructure metallic

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Influence of structural depth of laser-patterned steel surfaces on the solid lubricity of carbon nanoparticle coatings

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Friction 2023年第7期11卷 1276-1291页

作者： Timothy MACLUCAS Lukas DAUT Philipp GRÜTZMACHER Maria Agustina GUITAR Volker PRESSER Carsten GACHOT Sebastian SUAREZ Frank MÜCKLICH Chair of Functional Materials Saarland UniversitySaarbrücken 66123Germany Institute for Engineering Design and Product Development TU WienWien 1060Austria INM–Leibniz Institute for New Materials Saarbrücken 66123Germany Department of Materials Science&Engineering Saarland UniversitySaarbrücken 66123Germany Saarene-Saarland Center for Energy Materials and Sustainability Saarbrücken 66123Germany

Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining *** study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and *** laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel ***,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned *** ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 *** results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle ***,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing *** resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray *** friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely *** of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.

关键词： solid lubricant coatings carbon nanotubes carbon onions direct laser interference patterning(DLIP)surface structuring electrophoretic deposition(EPD)

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Neuromorphic nanocluster networks:Critical role of the substrate in nano-link formation

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Nano Research 2023年第7期16卷 10500-10506页

作者： Wenkai Wu Alexey V.Verkhovtsev Theodoros Pavloudis Andrey V.Solov’yov Richard E.Palmer Nanomaterials Lab Faculty of Science and EngineeringSwansea UniversityBay CampusFabian WaySA18ENSwanseaUK MBN Research Center Altenhöferallee 360438 Frankfurt am MainGermany School of Physics Faculty of SciencesAristotle University of ThessalonikiGR-54124 ThessalonikiGreece

Atomic cluster-based networks represent a promising architecture for the realization of neuromorphic computing systems,which may overcome some of the limitations of the current computing *** formation and breakage of links between the clusters are of utmost importance for the functioning of these computing *** paper reports the results of molecular dynamics simulations of synapse(bridge)formation at elevated temperature and thermal breaking processes between 2.8 nmsized Au1415 clusters deposited on a carbon substrate,a model ***,we find that the bridge formation process is driven by the diffusion of gold atoms along the substrate,no matter how small the gap between the clusters *** complementary simulations of the bridge breaking process reveal the existence of a threshold bias voltage to activate bridge rupture via Joule *** results provide an atomistic-level understanding of the fundamental dynamical processes occurring in neuromorphic cluster arrays.

关键词： atomic-switch network nanoclusters nanoparticles(NPs) clusters on surfaces synapse neuromorphics molecular dynamics(MD)

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Polarity,intramolecular charge transfer,and hydrogen bond comediated solvent effects on the optical properties of graphene quantum dots

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Nano Research 2023年第1期16卷 45-52页

作者： Yalei Hu Christof Neumann Lena Scholtz Andrey Turchanin Ute Resch-Genger Siegfried Eigler Institute of Chemistry and Biochemistry Freie Universität BerlinTakustraße 314195 BerlinGermany Institute of Physical Chemistry and Abbe Center of Photonics Friedrich Schiller University JenaLessingstraße 1007743 JenaGermany Federal Institute for Materials Research and Testing(BAM) Division BiophotonicsRichard Willstätter Straße 1112489 BerlinGermany

Graphene quantum dots(GQDs)have attracted increasing attention due to their favorable optical properties and have been widely used,e.g.,in the biomedical ***,the properties related to the chemical structure of GQDs,resulting in solventdependent optical properties,still remain ***,we present the synthesis of long-wavelength emitting GQDs with a size of about 3.6 nm via a solvothermal method using oxo-functionalized graphene(oxo-G)and p-phenylenediamine as precursors and their structural and surface chemical analysis by transmission electron and atomic force microscopy(TEM;AFM)as well as Fourier-transform infrared,Raman,and X-ray photoelectron spectroscopy(FTIR;Raman;XPS).Subsequently,the influence of solvent polarity and proticity on the optical properties of the as-prepared GQDs bearing–OH,–NH_(2),–COOH and pyridine surface groups was *** on the results of the absorption and fluorescence(FL)studies,a possible luminescence mechanism is *** observed solvent-induced changes in the spectral position of the FL maximum,FL quantum yield,and FL decay kinetics in protic and aprotic solvents of low and high polarity are ascribed to a combination of polarity effects,intramolecular charge transfer(ICT)processes,and hydrogen ***,the potential of GQDs for the optical sensing of trace amount of water was *** results of our systematic spectroscopic study will promote the rational design of GQDs and shed more light on the FL mechanism of carbon-based fluorescent nanomaterials.

关键词： graphene quantum dots(GQDs) polarity intramolecular charge transfer(ICT) hydrogen bond optical properties

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