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Estimation of drag forces caused by natural woody vegetation of different scales

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Journal of Hydrodynamics 2014年第4期26卷 608-623页

作者： JALONEN johanna JRVEL Juha department of Civil and Environmental Engineering Aalto University

To reliably estimate water levels and velocities in vegetated rivers and floodplains, flow resistance models based on physical plant properties are advantageous. The purpose of this study is （1） to assess the suitable parameterization of woody riparian vegetation in estimating the drag forces, （2） to address the effect of plant scale on the drag estimates and reconfiguration, and （3） to evaluate the applicability of three recently developed flow resistance models. Experiments on four tree species in a towing tank together with detailed characterization of tree properties were carried out to establish a novel dataset. despite the variability in the tree height （0.9 m-3.4 m）, the stem, leaf and total areas proved to be suitable characteristic dimensions for estimating the flow resistance at different scales. Evaluations with independent data revealed that the tested models produced reasonable results. The performance of the models was controlled by the parameter values used rather than the model structure or the plant scale.

关键词： drag force flow resistance woody vegetation modelling

A Myosin XI Tail domain Homologous to the Yeast Myosin Vacuole-Binding domain Interacts with Plastids and Stromules in Nicotiana benthamiana

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Molecular Plant 2009年第6期2卷 1351-1358页

作者： Amir Sattarzadeh johanna Krahmer Arnaud d. Germain Maureen R. Hanson department of Molecular Biology and Genetics Biotechnology Building Cornell University Ithaca NY 14853 USA

The actin cytoskeleton plays a role in mobility of many different organelles in plant cells, including chloroplasts, mitochondria, Golgi, and peroxisomes. While progress has been made in identifying the myosin motors involved in trafficking of various plant organelles, not all of the cargoes mobilized by different members of the myosin XI family have yet been identified. The involvement of myosins in chloroplast positioning and mitochondrial movement was demonstrated by expression of a virus-induced gene silencing （VIGS） construct in tobacco. When VIGS with two different conserved sequences from a myosin Xl motor was performed in plants with either GFP-labeled plastids or mitochondria, chloroplast positioning in the dark was abnormal, and mitochondrial movement ceased. Because these and prior obser- vations have implicated a role for myosins and the actin cytoskeleton in plastid and stromule movement, we searched for myosin tail domains that could associate with plastids and stromules. While a yellow fluorescent protein （YFP） fusion with the entire tail region of myosin XI-F was usually found only in the cytoplasm, we observed that an Arabidopsis or Nicotiana benthamiana YFP：：myosin XI-F tail domain homologous to the yeast myo2p vacuole-binding domain associated with plastids and stromules after transient expression in N. benthamiana. Taken together, these observations implicate myosin motor proteins in dynamics of plastids and stromules.

关键词： Chloroplast biology cytoskeleton dynamics mitochondria gene silencing fluorescent protein.

Cultivating more-than-human care: Exploring bird watching as a landscaping practice on the example of sand martins and flooded gravel pits

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Frontiers of Architectural Research 2022年第6期11卷 1205-1213页

作者： johanna Just Institute for Landscape and Urban Studies Prof.Teresa Galí-IzardChair of Being AliveDepartment of ArchitectureETH ZürichCH-8093 ZürichSwitzerland

The environmental crisis has created a demand for practices that build awareness about the interconnections of diverse forms of life,allowing humans to understand complex earthly relationships and reconnect with the land they *** paper contributes to this debate by investigating bird watching activities and their relevance for architects and landscape *** upon multispecies studies and the notion of landscape thinking,it examines the potential of birding as a caring landscaping *** analyzes the relationship between birders and sand martins in two case studies and probes how birders develop attentiveness for the birds and their shared *** investigation suggests that birding fosters care beyond the observed *** can trigger a landscaping practice comparable to landscape thinking that helps humans reconnect with the land,fostering response-able spatial design practices.

关键词： More-than-human Care Birding Landscaping Sand martin Gravel extraction

Finding stable multi-component materials by combining cluster expansion and crystal structure predictions

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npj Computational Materials 2023年第1期9卷 2137-2146页

作者： Adam Carlsson johanna Rosen Martin dahlqvist Materials design Department of PhysicsChemistryand Biology(IFM)Linköping UniversitySE-58183 LinköpingSweden

A desired prerequisite when performing a quantum mechanical calculation is to have an initial idea of the atomic positions within an approximate crystal *** atomic positions combined should result in a system located in,or close to,an energy ***,designing low-energy structures may be a challenging task when prior knowledge is scarce,specifically for large multi-component systems where the degrees of freedom are close to *** this paper,we propose a method for identification of low-energy crystal structures within multi-component systems by combining cluster expansion and crystal structure predictions with density-functional theory *** structure prediction searches are applied to the Mo_(2)AlB_(2) and Sc2AlB_(2) ternary systems to identify candidate structures,which are subsequently used to explore the quaternary(pseudo-binary)(Mo_(x)Sc_(1–x))2AlB_(2) system through the cluster expansion formalism utilizing the ground-state search ***,we show that utilizing low-energy structures found within the cluster expansion ground-state search as seed structures within crystal structure predictions of(Mo_(x)Sc_(1–x))2AlB_(2) can significantly reduce the computational *** this combined approach,we not only correctly identified the recently discovered Mo_(4/3)Sc_(2/3)AlB_(2) i-MAB phase,comprised of in-plane chemical ordering of Mo and Sc and with Al in a Kagomélattice,but also predict additional low-energy structures at various *** result demonstrates that combining crystal structure prediction with cluster expansion provides a path for identifying low-energy crystal structures in multi-component systems by employing the strengths from both frameworks.

关键词： structure cluster crystal

The Role of Inertia and dissipation in the dynamics of the director for a Nematic Liquid Crystal Coupled with an Electric Field

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Communications in Computational Physics 2015年第6期18卷 147-166页

作者： Peder Aursand johanna Ridder department of Mathematical Sciences Norwegian University of Science and TechnologyNO–7491 TrondheimNorway department of Mathematics University of OsloP.O.Box NO-1053BlindernOslo-0316Norway

We consider the dynamics of the director in a nematic liquid crystal when under the influence of an applied electric *** an energy variational approach we derive a dynamic model for the director including both dissipative and inertial forces.A numerical scheme for the model is proposed by extending a scheme for a related variational wave *** experiments are performed studying the realignment of the director field when applying a voltage difference over the liquid crystal *** particular,we study how the relative strength of dissipative versus inertial forces influence the time scales of the transition between the initial configuration and the electrostatic equilibrium state.

关键词： Nematic liquid crystals Freedericksz transition dynamics of director fields

Nickela-electrocatalyzed sulfide and phosphine oxygenations with water

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Science China Chemistry 2021年第6期64卷 873-874页

作者： Long Yang johanna Frey Lutz Ackermann Institut für Organische und Biomolekulare Chemie Georg-August-Universität GöttingenTammannstrasse 2Göttingen 37077Germany Wöhler Research Institute for Sustainable Chemistry(WISCh) Georg-August-Universität GöttingenTammannstrasse 2Göttingen 37077Germany

Molecular electrochemistry has emerged as an environmentally-friendly *** major recent momentum was gained in electrocatalyzed bond activations by earth-abundant 3 d transition metals[1],cost-effective nickela-electrocatalysis continuous to be underdevelopment for electrocatalysis[2].Nickel is an essential component of metalloproteins involved in catalytic aerobic oxygenation processes,for which nickel-dioxygen species were proposed as the key catalytic species[3].

关键词： catalyzed nickel Nickel

EULER SCHEME FOR FRACTIONAL dELAY STOCHASTIC dIFFERENTIAL EQUATIONS BY ROUGH PATHS TECHNIQUES

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Acta Mathematica Scientia 2019年第3期39卷 747-763页

作者： johanna GARZON Samy TINdEL Soledad TORRES departamento de Matematicas Universidad Nacional de ColombiaBogota D.C.Colombia department of Mathematics Purdue University150 N.University StreetW.LafayetteIN 47907USA Facultad de Ingenierza CIMF AV Universidad de ValparaisoCasilla 123-V4059 ValparaisoChile

In this note, we study a discrete time approximation for the solution of a class of delayed stochastic differential equations driven by a fractional Brownian motion with Hurst parameter H ∈(1/2,1). In order to prove convergence, we use rough paths techniques. Theoretical bounds are established and numerical simulations are displayed.

关键词： Fractional Brownian motion stochastic differential equations rough paths,discrete time approximation

What do We Really Know about Cellulose Biosynthesis in Higher Plants?

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Journal of Integrative Plant Biology 2010年第2期52卷 161-175页

作者： Gea Guerriero johanna Fugelstad Vincent Bulone division of Glycoscience School of BiotechnologyRoyal Institute of TechnologyAlbaNova University CenterSE-106 91 StockholmSweden

Cellulose biosynthesis is one of the most important biochemical processes in plant biology. despite the considerable progress made during the last decade, numerous fundamental questions related to this key process in plant development are outstanding. Numerous models have been proposed through the years to explain the detailed molecular events of cellulose biosynthesis. Almost all models integrate solid experimental data with hypotheses on several of the steps involved in the process. Speculative models are most useful to stimulate further research investigations and bring new exciting ideas to the field. However, it is important to keep their hypothetical nature in mind and be aware of the risk that some undemonstrated hypotheses may progressively become admitted. In this review, we discuss the different steps required for cellulose formation and crystallization, and highlight the most important specific aspects that are supported by solid experimental data.

关键词： cell What do We Really Know about Cellulose Biosynthesis in Higher Plants

Proteomics reveals differential adsorption of angiogenic platelet lysate proteins on calcium phosphate bone substitute materials

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Regenerative Biomaterials 2022年第1期9卷 636-649页

作者： Richard da Costa Marques johanna Simon Cyril d’Arros Katharina Landfester Kerstin Jurk Volker Mailänder dermatology Clinic University Medical Center of the Johannes Gutenberg-University Mainz55131 MainzGermany Max Planck Institute for Polymer Research 55128 MainzGermany INSERM UMR 1229Regenerative Medicine and SkeletonONIRISUniversitéde Nantes44042 NantesFrance Biomatlante—Advanced Medical Solutions Group Plc 44360 Vigneux-de-BretagneFrance Center for Thrombosis and Hemostasis(CTH) University Medical Center of the Johannes Gutenberg-University Mainz55131 MainzGermany

Protein adsorption on biomaterials for bone substitution,such as calcium phosphates(CaP),evokes biological responses and shapes the interactions of biomaterials with the surrounding biological *** adsorb when CaP materials are combined with growth factor-rich hemoderivatives prior to implantation to achieve enhanced angiogenesis and stimulate new bone ***,the identification of the adsorbed proteins and their angiogenic effect on bone homeostasis remain incompletely *** this study,we analyzed the adsorbed complex protein composition on CaP surfaces when using the hemoderivatives plasma,platelet lysate in plasma(PL),and washed platelet lysate proteins(wPL).We detected highly abundant,non-regenerative proteins and anti-angiogenic proteins adsorbed on CaP surfaces after incubation with PL and wPL by liquid chromatography and mass spectrometry(LC–MS)***,we measured a decreased amount of adsorbed pro-angiogenic growth *** formation assays with human umbilical endothelial cells demonstrated that the CaP surfaces only stimulate an angiogenic response when kept in the hemoderivative medium but not after washing with *** results highlight the necessity to correlate biomaterial surfaces with complex adsorbed protein compositions to tailor the biomaterial surface toward an enrichment of pro-angiogenic factors.

关键词： protein adsorption calcium phosphates proteomics angiogenesis platelet lysate