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Generalized food-deceptive orchid species flower earlier and occur at lower altitudes than rewarding ones

Journal of Plant Ecology 2010年第4期3卷 243-250页

作者： Loıc Pellissier pascal vittoz Antonina Ingrid Internicola Luc Daniel Bienvenu Gigord Department of Ecology and Evolution University of LausanneBiophoreCH-1015 LausanneSwitzerland Faculty of Geosciences and Environment University of LausanneBiophoreCH-1015 LausanneSwitzerland Conservatoire Botanique National de Mascarin 2 rue du Pe`re GeorgesLes Colimac xons97436 Saint-LeuLa Re´unionFrance Present address:Department of Biological Sciences 2500 University Drive N.W.University of CalgaryCalgary ABAlbertaCanada T2N 1N4

Aims Food-deceptive pollination,in which plants do not offer any food reward to their pollinators,is common within the *** food-deceptive orchids are poorer competitors for pollinator visitation than rewarding orchids,their occurrence in a given habitat may be more constrained than that of rewarding *** particular,the success of deceptive orchids strongly relies on several biotic factors such as interactions with co-flowering rewarding species and pollinators,which may vary with altitude and over *** study compares generalized food-deceptive(*** sexually deceptive)and rewarding orchids to test whether(i)deceptive orchids flower earlier compared to their rewarding counterparts and whether(ii)the relative occurrence of deceptive orchids decreases with increasing *** To compare the flowering phenology of rewarding and deceptive orchids,we analysed data compiled from the literature at the species level over the occidental Palaearctic *** flowering phenology can be constrained by the latitudinal distribution of the species and by their phylogenetic relationships,we accounted for these factors in our *** compare the altitudinal distribution of rewarding and deceptive orchids,we used field observations made over the entire Swiss territory and over two Swiss mountain *** Findings We found that deceptive orchid species start flowering earlier than rewarding orchids do,which is in accordance with the hypotheses of exploitation of naive pollinators and/or avoidance of competition with rewarding co-occurring ***,the relative frequency of deceptive orchids decreases with altitude,suggesting that deception may be less profitable at high compared to low altitude.

关键词： altitude timing of flowering food-deception European orchids Orchidaceae biogeography

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Plant functional and phylogenetic turnover correlate with climate and land use in the Western Swiss Alps

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Journal of Plant Ecology 2014年第5期7卷 439-450页

作者： Charlotte Ndiribe Loïc Pellissier Anne Dubuis pascal vittoz Nicolas Salamin Antoine Guisan Department of Ecology and Evolution University of LausanneBiophore BuildingUnil-SorgeVaudLausanne CH-1015Switzerland Swiss Institute of Bioinformatics GenopodeLausanne CH-1015Switzerland The Arctic Research Centre Department of BioscienceAarhus UniversityAarhusDenmark Institute of Earth Surface Dynamics GeopolisUniversity of LausanneLausanne CH-1015Switzerland

Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological ***,researchers are relying on the functional and phylogeneticβ-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among *** present study investigated how plant functional and phylogeneticβ-diversity change along key environmental and spatial gradients in the Western Swiss *** Using the quadratic diversity measure based on six functional traits-specific leaf area,leaf dry matter content,plant height,leaf carbon content,leaf nitrogen content and leaf carbon to nitrogen content alongside a species-resolved phylogenetic tree-we relate variations in climate,spatial geographic,land use and soil gradients to plant functional and phylogenetic turnover in mountain commu-nities of the Western Swiss *** Findings Our study highlights two main ***,climate and land-use factors play an important role in mountain plant community ***,the overlap between plant functional and phy-logenetic turnover along these gradients correlates with the low phylogenetic signal in traits,suggesting that in mountain land-scapes,trait lability is likely an important factor in driving plant community ***,we demonstrate the importance of climate and land-use factors in plant functional and phyloge-netic community turnover and provide valuable complementary insights into understanding patterns ofβ-diversity along several ecological gradients.

关键词： ecological gradients functional and phylogeneticβ-diversity plant community turnover Rao’s quadratic entropy index(Q) Western Swiss Alps

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Substrate topography as a powerful tool to modify glial cell biology and interactions

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Neural Regeneration Research 2025年第5期20卷 1390-1391页

作者： pascal Achenbach Haktan Altinova Gary A.Brook Institute of Neuropathology RWTH Aachen University Hospital Department of Neurosurgery RWTH Aachen University Hospital Aachen Germany Berlin State Office for Health and Social Affairs(LAGeSo) BerlinGermany

Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal *** normal conditions,maintenance of this complex system is structurally and functionally supported by astrocytes (ACs)and other glial cells,the processes of which form a framework surrounding neuronal cell bodies,dendrites,axons,and synapses.

关键词： injuries topography system

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Useful zero friction simulations for assessing MBS codes pascal’s formula giving wheelsets frequency for zero wheel-rail friction

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Theoretical & Applied Mechanics Letters 2022年第3期12卷 145-155页

作者： Jean Pierre pascal pascal Coding Rue d’ErquyPleneuf-Val-Andre F-22370France

Present study provides a simple analytical formula,the“Klingel-like formula”or“pascal’s Formula”that can be used as a reference to test some results of existing railway codes and specifically those using rigid *** develops properly the 3D Newton-Euler equations governing the 6 degrees of freedom(DoF)of unsuspended loaded wheelsets in case of zero wheel-rail friction and constant ***,by solving numerically these equations,we got pendulum like harmonic oscillations of which the calculated angular frequency is used for assessing the accuracy of the proposed formula so that it can in turn be used as a fast practical target for testing multi-body system(MBS)railway *** to the harmonic property of these pendulum-like oscillations,the squareω2 of their angular frequency can be made in the form of a ratio K/M where K depends on the wheelset geometry and load and M on its *** on K and M are useful to understand wheelsets *** analytical formula is derived from the first order writing of full trigonometric Newton-Euler equations by setting zero elastic wheel-rail penetration and by assuming small *** trigonometric equations are numerically solved to assess that the formula providesω2 inside a 1%accuracy for usual wheelsets *** decreasing the conicity down to 1×10^(−4) rad,the relative formula accuracy is under 3×10^(−5).In order to test the formula reliability for rigid contact formulations,the stiffness of elastic contacts can be increased up to practical rigidity(Hertz stiffness×1000).

关键词： Unsuspended wheelsets Klingel formula Rigid contact Harmonic oscillation Multi body system railway codes Code validation

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On the Mechanization of Straightedge and Compass Constructions

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Journal of Systems Science & Complexity 2019年第1期32卷 124-149页

作者： SCHRECK pascal Université de Strasbourg UFR de Mathématique et Informatique-ICube

The geometric constructions obtained with only straightedge and compass are famous and play a special role in the development of geometry. On the one hand, the constructibility of ?gures is a key ingredient in Euclid geometry and, on the other hand, unconstructibility gave birth to famous open problems of the ancient Greece which were unlocked only in the nineteenth century using discoveries in algebra. This paper discusses the mechanization of straightedge and compass constructions. It focuses on the algebraic approaches and presents two methods which are implemented; one is due to Lebesgue and the other one was jointly designed by Gao and Chou. Some links between the algebraic approach of constructions and synthetic geometry are described.

关键词： Geometric knowledge-based systems regular chains straightedge and compass constructibility triangle problems Wu's method

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Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report

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Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： pascal J.Goldschmidt-Clermont Aisha Khan George Jimsheleishvili Patricia Graham Adriana Brooks Risset Silvera Alexander J.P.Goldschmidt Damien D.Pearse W.Dalton Dietrich Allan D.Levi James D.Guest Miller School of Medicine University of MiamiMiamiFLUSA Stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The Miami Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann cell function may also be ***,important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been *** case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral *** initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and *** patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron *** confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in *** a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrophic lateral sclerosis exosomes infusion neuromuscular junction Schwann cell

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GRADIENT FLOW FINITE ELEMENT DISCRETISATIONS WITH ENERGY-BASED ADAPTIVITY FOR EXCITED STATES OF SCHRÖDINGER'S EQUATION

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Journal of Computational Mathematics 2023年第5期41卷 933-955页

作者： pascal Heid Mathematical Institute University of OxfordWoodstock RoadOxford OX26GGUK

The purpose of this paper is to verify that the computational scheme from[Heid et al.,Gradient flow finite element discretizations with energy-based adaptivity for the Gross–Pitaevskii equation,***.436(2021)]for the numerical approximation of the ground state of the Gross–Pitaevskii equation can equally be applied for the effective approximation of excited states of Schr¨odinger’s *** procedure employs an adaptive interplay of a Sobolev gradient flow iteration and a novel local mesh refinement strategy,and yields a guaranteed energy decay in each step of the *** computational tests in the present work highlight that this strategy is indeed able to approximate excited states,with(almost)optimal convergence rate with respect to the number of degrees of freedom.

关键词： Schrodinger’s equation Excited states Gradient flows Adaptive finite element methods

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SUSY searches at ATLAS

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Frontiers of physics 2013年第3期8卷 248-256页

作者： pascal Pralavoriot CPPM University Aix-Marseille and CNRS/IN2P3 Marseille France

Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. The ATLAS experiment at the LHC searches for signs of supersymmetry in a large variety of signatures involving events with abnormal production of missing transverse momentum, jets, leptons, third generation fermions, gauge bosons or massive long-lived particles. A summary of the most recent results obtained in these searches is presented.

关键词： supersymmetry (SUSY) ATLAS LHC

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Fluid dynamic modeling of junctions in internal combustion engine inlet and exhaust systems

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Journal of Thermal Science 2010年第5期19卷 410-418页

作者： David Chalet pascal Chesse Internal Combustion Engine Team Laboratory of Fluid Mechanics-UMR CNRS 6598 Ecole Centrale de NantesBP 92101 44321 NantesFrance

The modeling of inlet and exhaust systems of internal combustion engine is very important in order to evaluate the engine *** paper presents new pressure losses models which can be included in a one dimensional engine simulation *** a first part,a CFD analysis is made in order to show the importance of the density in the modeling ***,the CFD code is used,as a numerical test bench,for the pressure losses models *** coefficients depend on the geometrical characteristics of the junction and an experimental validation is made with the use of a shock tube test *** the models are then included in the engine simulation code of the *** numerical calculation of unsteady compressible flow,in each pipe of the inlet and exhaust systems,is made and the calculated engine torque is compared with experimental measurements.

关键词： compressible flow gas dynamics pressure wave propagation discharge coefficient internal combustion engine CFD simulation

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Media-specific rate allocation in heterogeneous wireless networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 713-726页

作者： JURCA Dan FROSSARD pascal Ecole Polytechnique Fédérale de Lausanne Signal Processing Institute Lausanne CH-1015 Switzerland

We address the problem of joint path selection and rate allocation in multipath wireless streaming, in order to optimize a media specific quality of service. We leverage on the existence of multiple parallel wireless services, in order to enhance the received video quality at a wireless client. An optimization problem is proposed, aimed at minimizing a video distortion metric based on sequence-dependent parameters, and transmission channel characteristics, for a given wireless network infrastructure. Even if joint optimal path selection and rate allocation is in general an NP complete problem, an in-depth analysis of the media distortion evolution allows defining a low complexity optimal streaming strategy, under reasonable network assumptions. In particular, we show that a greedy allocation of rates along paths with increasing error probability leads to an optimal solution. We argue that a network path should not be chosen for transmission, unless all other available paths with lower error probability have been chosen. Moreover, the chosen paths should be used at their maximum end-to-end bandwidth. These results are demonstrated for both independent network paths, and non-disjoint channel segments, in generic network topologies. Simulation results showed that the optimal rate allocation carefully trades off total encoding/transmission rate, with the end-to-end transmission error probability and the number of chosen paths. In many cases, the optimal rate allocation provides more than 20% improvement in received video quality, compared to heuristic-based algorithms.

关键词： Multipath streaming, Path selection, Rate allocation, Video streaming

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