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Drought Tolerance and Recovery of the Sedge Carex planostachys (Cyperaceae) from Central Texas Woodlands

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American Journal of Plant Sciences 2024年第9期15卷 746-765页

作者： e. Rob Wayne Oscar William Van Auken Natural Sciences Department St. Philips College San Antonio USA Department of Integrative Biology The University of Texas at San Antonio San Antonio USA

Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditions impose survival challenges to plants in dry areas. Some plants have plasticity responses to soil water content and continued normal though reduced functions through droughts, but most herbaceous plants do not survive. Limited previous studies have suggested C. planostachys is tolerant of drought. Physiological responses of C. planostachys from Juniperus woodlands was examined is this study to determine how long plants could survive without water and if they are capable of recovery from very negative water potentials beyond what is considered the permanent wilting point for most herbaceous plants. Plants were placed in pots in partial shade in this experiment. Water loss from the soil with plants was an inverse 2nd order polynomial function with soil water decreasing from 32% to 8% by day 28 of the study. Leaf water potential was also an inverse 2nd order polynomial function but did not decline significantly until 14 days without watering. Leaf water potential was −10.0 MPa after 35 days without watering. Non-watered plants Anet, (photosynthetic rate) was significantly lower compared to the water treatment by day 21 as was stomatal conductance and transpiration. When non-watered plants were watered after 21, 28 or 35 days, full recovery of physiological responses occurred within 7 days. The length of time that C. planostachys was able to withstand drought was greater than the annual trends in lack of precipitation during springtime in this area. Carex planostachys can photosynthesize at water stress between −8 and −10 MPa. Carex planostachys drought and shade tolerance enables it to occupy an understory niche devoid of other herbaceous plants.

关键词： CO2 Uptake Conductance Gas exchange Photosynthesis Respiration Transpiration Water Stress Water Potential.

Phenomenological model for torsional galloping of an elastic flat plate due to hydrodynamic loads

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Journal of Hydrodynamics 2014年第1期26卷 57-65页

作者： FeRNANDeS antonio Carlos ARMANDeI Mohammadmehdi Department of Naval and Ocean engineering COPPE/UFRJ

This study investigates the torsional galloping phenomenon, an instability type flow-induced oscillation, in an elastic stru-cture due to hydrodynamic loads into the water current. The structure applied here is a rectangular flat plate with an elastic axis in its mid-chord length. The elasticity is provided by torsion spring. The flat plate has only one degree of freedom which is rotation in pure yaw about its axis. It is observed that as the current speed is higher than a critical velocity, the flat plate becomes unstable. The instability leads to torsional galloping occurrence, as a result of which the flat plate begins to yaw about the elastic axis. By testing two different chord lengths each with several torsion spring rates, the flat plate behavior is investigated and three different responses are recognized. Then, a phenomenological model is developed with the original kernel in the form of the van der Pol-Duffing equa-tion. The model explains these three responses observed experimentally.

关键词： torsional galloping flow-induced oscillation phenomenological model van der Pol-Duffing equation

Veterans utilizing a federally qualified health center: a clinical snapshot

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Military Medical Research 2023年第1期10卷 134-136页

作者： Thad e.Abrams Bruce Alexander antonio Flores M.Bryant Howren VHA Office of Rural Health Veterans Rural Health Resource CenterIowa CityIA 52246USA Carver College of Medicine The University of IowaIowa CityIA 52242USA Center for Access Delivery Research and evaluation(CADRe) VA Iowa City Healthcare SystemIowa CityIA 52246USA Community Health Centers of Southeastern Iowa West BurlingtonIA 52655USA Department of Behavioral Sciences and Social Medicine College of MedicineFlorida State UniversityTallahasseeFL 32306USA Florida Blue Center for Rural Health Research and Policy College of MedicineFlorida State UniversityTallahasseeFL 32306USA

Dear editor,Te Veterans Health Administration(VHA)provides healthcare for over 9 million enrolled veterans with approximately 2.7 million of those residing in rural areas[1].Te MISSION Act of 2018 emphasizes VHA collaboration with Federally Qualifed Healthcare Centers(FQHC)to serve rural residing veterans and nearly all existing collaborations involve arrangement of payment for community-based care by VHA to ***,there is a paucity of descriptive clinical data on existing cross-system collaborations which may help characterize these veterans and aid understanding of conditions for which they may receive treatment across *** data has implications for workforce training,development,and resource allocation[2].Te objective of this report is to describe diferent clinical profles between two mutually exclusive samples:veterans engaged in FQHC only use,and VHA-enrolled veterans engaged in dual VHA and FQHC use.

关键词： Veterans Federally qualified healthcare centers Healthcare utilization Dual use Mental health

Ligninolytic Peroxidase-Like Activity of a Synthetic Metalloporphine Immobilized onto Mercapto-Grafted Crosslinked PVA Inspired by the Active Site of Cytochrome P450

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催化学报 2011年第11期32卷 1663-1666页

作者： Paolo ZUCCA antonio ReSCIGNO enrico SANJUST Dipartimento di Scienze e Tecnologie Biomediche Università di Cagliari Monserrato 09042 Italy Consorzio per lo Sviluppo dei Sistemi a Grande Interfase Sesto Fiorentino 50019 Italy

A synthetic metalloporphine was immobilized onto a PVA-based and mercapto-grafted solid support, emulating the active site of cytochrome P450. Its ligninolytic peroxidase-like catalytic activity was studied. The coordinated mercapto ligand significantly affected the catalytic features of the catalyst because the oxidation of lignin-model compounds was very slow by comparison with imidazoleand pyridine-coordinated immobilized metalloporphines. Conversely, the catalyst efficiently bleached several industrial dyes and thus demonstrated promising activity for this application. Based on this altered substrate specificity the oxygen-donor catalytic route seems to be more favorable than a single electron oxidation pathway.

关键词： porphine porphyrin lignin peroxidase cytochrome P450 biomimetic

Mechanics of tubular helical assemblies:ensemble response to axial compression and extension

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Acta Mechanica Sinica 2021年第2期37卷 173-186页

作者： Jacopo Quaglierini Alessandro Lucantonio antonio DeSimone Department of excellence in Robotics and AI The BioRobotics InstituteScuola Superiore Sant'Anna56127 PisaItaly SISSA-Scuola Intemazionale Superiore di Studi Avanzati 34136 TriesteItaly

Nature and technology often adopt structures that can be described as tubular helical ***,the role and mechanisms of these structures remain *** this paper,we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchholf rods,arranged in pairs with opposite chirality and connected by pin joints,both analytically and *** first focus on compression and find that,whereas a single helical rod would buckle,the rods of the assembly deform coherently as stable helical shapes wound around a common ***,we investigate the response of the assembly under different boundary conditions,highlighting the emergence of a central region where rods remain circular ***,we study the effects of different hypotheses on the elastic properties of rods,i.e.,stress-free rods when straight versus when circular helices,Kirchhoff’s rod model versus Sadowsky’s ribbon *** up,our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods,as well as some interesting features,and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.

关键词： Computational mechanics Helical assemblies Kirchhoff rod Sadowsky ribbon ensemble response

Algorithms to Compute the Largest Invariant Set Contained in an Algebraic Set for Continuous-Time and Discrete-Time Nonlinear Systems

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Ieee/CAA Journal of Automatica Sinica 2020年第1期7卷 57-69页

作者： Laura Menini Corrado Possieri antonio Tornambè Dipartimento di Ingegneria Industriale Universitàdi Roma Tor VergataRoma 00133Italy Istituto di Analisi dei Sistemi ed Informatica“A.Ruberti ”Consiglio Nazionale delle Ricerche(IASI-CNR)Roma 00185Italy Dipartimento di Ingegneria Civile e Ingegneria Informatica Universitàdi Roma Tor VergataRoma 00133Italy

In this paper, some computational tools are proposed to determine the largest invariant set, with respect to either a continuous-time or a discrete-time system, that is contained in an algebraic set. In particular, it is shown that if the vector field governing the dynamics of the system is polynomial and the considered analytic set is a variety, then algorithms from algebraic geometry can be used to solve the considered problem. examples of applications of the method(spanning from the characterization of the stability to the computation of the zero dynamics) are given all throughout the paper.

关键词： Asymptotic stability discrete-time systems invariance nonlinear systems

Mechanical properties characterization of different types of masonry infill walls

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Frontiers of Structural and Civil engineering 2020年第2期14卷 411-434页

作者： Andre FURTADO Hugo RODRIGUeS antonio AReDe Humberto VARUM CONSTRUCT-LeSe Department of Civil EngineeringFaculty of EngineeringUniversity of PortoPorto 4200-465Portugal R1SCO School of Technology and ManagementPolytechnic Institute of LeiriaLeiria 2411-901Portugal

It is remarkable,the recent advances concerning the development of numerical modeling frameworks to simulate the infill panels'seismic ***,there is a lack of experimental data of their mechanical properties,which are of full importance to calibrate the numerical *** primary objective of this paper is to present an extensive experimental campaign of mechanical characterization tests of infill masonry walls made with three different types of masonry units:lightweight vertical hollow concrete blocks and hollow clay *** different types of experimental tests were carried out,namely:compression strength tests,diagonal tensile strength tests,and flexural strength tests parallel and perpendicular to the horizontal bed joints.A total amount of 80 tests were carried out and are reported in the present *** second objective of this study was to compare the mechanical properties of as-built and existing infill *** results presented and discussed herein,will be in terms of strain-stress curves and damages observed within the *** was observed a fragile behavior in the panels made with hollow clay horizontal bricks,without propagation of *** plaster increased the flexural strength by 57%.

关键词： masonry infill walls experimental characterization compression strength shear diagonal strength flexural strength

Modular Filter Convergence Theorems for Urysohn Integral Operators and Applications

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Acta Mathematica Sinica,english Series 2013年第6期29卷 1055-1066页

作者： antonio BOCCUTO Xenofon DIMITRIOU Dipartimento di Matematica e Informatica via Vanvitelli Department of Mathematics University of Athens Panepistimiopolis

We prove some versions of modular convergence theorems for nonlinear Urysohn-type integral operators with respect to filter convergence. We consider pointwise filter convergence of functions giving also some applicati... 详细信息

关键词： egorov filter Lebesgue filter filter convergence filter exhaustiveness filter singularity integral operator Mellin operator modular convergence modular space

Pseudo-orthogonality for graph 1-Laplacian eigenvectors and applications to higher Cheeger constants and data clustering

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Frontiers of Mathematics in China 2022年第4期17卷 591-623页

作者： antonio Corbo eSPOSITO Gianpaolo PISCITeLLI Dipartimento di Ingegneria elettrica e dell’Informazione“M.Scarano” Universitàdegli Studi di Cassino e del Lazio MeridionaleVia G.Di Biasio n.4303043Cassino(FR)Italy

The data clustering problem consists in dividing a data set into prescribed groups of homogeneous *** is an NP-hard problem that can be relaxed in the spectral graph theory,where the optimal cuts of a graph are related to the eigenvalues of graph *** this paper,we first give new notations to describe the paths,among critical eigenvectors of the graph 1-Laplacian,realizing sets with prescribed *** introduce the pseudo-orthogonality to characterize m_(3)(G),a special eigenvalue for the graph ***,we use it to give an upper bound for the third graph Cheeger constant h_(3)(G),that is,h_(3)(G)≤m_(3)(G).This is a first step for proving that the k-th Cheeger constant is the minimum of the 1-Laplacian Raylegh quotient among vectors that are pseudo-orthogonal to the vectors realizing the previous k−1 Cheeger ***,we apply these results to give a method and a numerical algorithm to compute m3(G),based on a generalized inverse power method.

关键词： Graph 1-Laplacian graph Cheeger constants pseudo-orthogonality critical values data clustering