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A POSTERIORI ERROR ANALYSIS OF A FULLY-MIXED FINITE ELEMENT METHOD FOR A TWO-DIMENSIONAL FLUID-SOLID INTERACTION PROBLEM

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Journal of Computational Mathematics 2015年第6期33卷 606-641页

作者： Carolina Dominguez Gabriel N. Gatica salim meddahi Instituto de Ciencias Fisicas y Matemdticas facultad de ciencias universidad austral de chile Avenida Eduardo Morales Miranda - campus isla teja valdivia chile CI2 MA and Departamento de Ingenieria Matematica Universidad de concapcion casilla 160 concepcion chile Departamento de Matemdticas Facultad de ciencias universidad de oiede calvo satela s/n oviedo espana

In this paper we develop an a posteriori error analysis of a fully-mixed finite element method for a fluid-solid interaction problem in 2D. The media are governed by the elas-todynamic and acoustic equations in time-harmonic regime, respectively, the transmission conditions are given by the equilibrium of forces and the equality of the corresponding normal displacements, and the fluid is supposed to occupy an annular region surrounding the solid, so that a Robin boundary condition imitating the behavior of the sommerfeld condition is imposed on its exterior boundary. Dual-mixed approaches are applied in both domains, and the governing equations are employed to eliminate the displacenent a of the solid and the pressure p of the fluid. In addition, since both transmission conditions become essential, they are enforced weakly by means of two suitable lahrange multipliers The unknowns of the solid and the fluid are then approximated by a conforming galerkin scheme defined in terms of PEERS elements in the solid, Raviart-Thomas of lowest order in the fluid, and continuous piecewise linear functions on the boundary, As the main con-tribution of this work, we derive a reliable and efficient residual-based a posteriori error estimator for the aforedescribed coupled problem. Some numerical results confirming the properties of the estimator are also reported.

关键词： Mixed finite elements Helmholtz equation Elastodynamic equation A poste- riori error analysis

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Functional diversity in an Andean subparamo affected by wildfire in Colombia

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Plant Diversity 2023年第4期45卷 385-396页

作者： Korina Ocampo-Zuleta Angela Parrado-Rosselli Instituto de Ciencias Ambientales y Evolutivas.Facultad de Ciencias.Universidad Austral de Chile.campus isla teja 5090000 ValdiviaChile Programa de Doctorado en Ciencias Mencion Ecología y Evolucion Escuela de GraduadosFacultad de CienciasUniversidad Austral de ChileValdiviaChile Jardín Botanico de Bogota Jose Celestino Mutis Subdireccion CientíficaLínea de Investigacion en Restauracion Ecologica111071BogotaColombia Facultad del Medio Ambiente y Recursos Naturales Universidad Distrital Francisco Jose de CaldasSede Vivero111711BogotaColombia

Recently,the Andean subparamo in Colombia has experienced severe wildfires,but little is known about the functional composition of recovering or not after a ***,we examined the functional community composition subparamo affected byfire in *** documented how functional traits changed 31 months after the disturbance and compared them with an unburned *** sampled from one to two years after the fire every four months,then registered all recruits in 1655m *** individuals were classified into strategy functional groups based on the traits of persistence and *** first group was stem type and regeneration mechanism(seedling and resprout),and the second was fruit type and dispersal *** investigated the degree to which functional diversity changes plant communities over time(woody and non-woody),and we compared it with an unburned *** most relevant results showed that resprouts and seed regenerated increased post-fire time and significant differences between sampling *** anemochory is the most relevant dispersal mode that indicates the community capacity to colonize the new gaps opened by the fire *** discuss how wildfire appears to be a triggering factor for persistence and dispersal strategy groups in subparamo burned given their characteristics of tolerance to *** this reason,a greater functional divergence between the ecosystems studied post-fire recovery has been related to higher levels of biodiversity at the landscape scale due to the high degree of endemism and significant differences in species composition between paramos.

关键词： Subparamo Cerro aguanoso Dispersal mode Functional traits Postfire regeneration

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Variable-top stem biomass equations at tree-level generated by a simultaneous density-integral system for second growth forests of roble, raulí,and coigüe in Chile

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Journal of Forestry Research 2019年第3期30卷 993-1010页

作者： Carlos Valenzuela Eduardo Acuna Alicia Ortega Geronimo Quinonez-Barraza Jose Corral-Rivas Jorge Cancino Departamento Manejo de Bosques y Medio Ambiente Facultad de Ciencias ForestalesUniversidad de Concepcion Victoria 631Barrio Universitario4070386 ConcepcionChile Instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austral de ChileCampus Isla Teja5110566 ValdiviaChile Campo Experimental Valle del Guadiana Instituto Nacional de Investigaciones Forestales Agricolas y Pecuarias (INIFAP)km 4.5 Carretera Durango-Mezquital34170 DurangoDGOMexico Instituto de Silvicultura e Industria de la Madera Universidad de Juarez del Estado de Durango34120 DurangoMexico

Variable-top stem biomass models at the tree level for second growth forests of roble (Nothofagus obliqua), rauli(Nothofagus alpina), and coigüe (Nothofagus dombeyi) were fitted by a simultaneous density-integral system, which combines a stem taper model and a wood basic density model. For each model, an autoregressive structure of order 2 and a power equation of residual variance were incorporated to reduce residual autocorrelation and heteroscedasticity, respectively. By using dummy variables in the regression analysis, zonal effects on the parameters in the variable-top stem biomass equations were detected in roble. Consequently, equations for clusters of zones were obtained. These equations presented significant parameters and a high precision in both fitting and validation processes (i.e., CV<11.5% and CVp<11.9%, respectively), demonstrating that they are unbiased. The advantage of these types of functions is that they provide estimates of volume and biomass of sections of the stem, defined between any two points of the stem in the three species. Thus, depending on the final use of the wood and the dimensions of the tree, a stem fraction can be quantified in units of volume and the remaining fraction in units of weight.

关键词： Autocorrelation Density-integral Dummy variables Autoregressive error structure Heteroscedasticity

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Effect of Cellulose Microfibers from Sugar Beet Pulp By-product on the Reinforcement of HDPE Composites Prepared by Twin‐screw Extrusion and Injection Molding

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Journal of Bionic Engineering 2023年第1期20卷 349-365页

作者： Abdelghani Boussetta Anass Ait Benhamou Francisco J.Barba Nabil Grimi Mario J.Simirgiotis Amine Moubarik Laboratory of Chemical Processes and Applied Materials Poly Disciplinary FacultySultan Moulay Slimane UniversityBP 592Beni-MellalMorocco Materials Science Energy and Nanoengineering(MSN)DepartmentMohammed VI Polytechnic UniversityLot 660-Hay Moulay Rachid43150Ben GuerirMorocco Materials Science and Process Optimization Laboratory Faculty of Science SemlaliaCadi Ayyad University40000MarrakechMorocco Nutrition and Food Science Area Preventive Medicine and Public HealthFood ScienceToxicology and Forensic Medicine DepartmentFaculty of PharmacyUniversitat de ValènciaAvda.Vicent Andrés Estelléss/n46100BurjassotValènciaSpain Sorbonne Université Universitéde Technologie de CompiègneLaboratoire Transformations Intégrées de La Matière Renouvelable(UTC/ESCOMEA 4297 TIMR)Centre de recherches RoyallieuCS 6031960203Compiègne CedexFrance campus isla teja Institute of PharmacyFaculty of SciencesUniversidad Austral de Chile5090000ValdiviaChile

The aims of this work turn towards the valorization of the underutilized Raw Sugar Beet Pulp by-product to produce white Cellulose Microfibers(CMFs),and its potential effect as a reinforcement for the development of High-Density Polyethylene(HDPE)*** CMFs were first obtained by subjecting raw SBP to alkali and bleaching *** characterization techniques were performed to confirm the successful removal of the amorphous compounds from the surface of individual fibers,including SEM,XRD,TGA,and FT-IR *** CMF loadings(5–10 wt%)were incorporated as bio-fillers into HDPE polymer to evaluate their reinforcing ability in comparison to raw and alkali-treated SBP using twin-screw extrusion followed by injection ***–(Ethylene–Butene)–Styrene Three-Block Co-Polymer Grafted with Maleic Anhydride was used as a compatibilizer to improve the interfacial adhesion between fibers and the ***,mechanical,and rheological properties of the produced composite samples were *** was found that the Young’s modulus were gradually increased with increasing of fibers loadings,with a maximum increase of 30%and 26%observed for composite containing 10 wt%of CMFs and raw SBP,respectively,over neat ***,the use of coupling agent enhances the ductile behavior of the *** was also found that all fiber improves the hardness and toughness behavior of all reinforced composites as well as the complex modulus particularly at 10 wt%.The thermal stability slightly increases with the addition of *** study demonstrates a new route for the valorization of SBP *** fibers can be considered as a valuable bio-fillers candidate for the development of composite materials with enhanced properties.

关键词： Sugar beet pulp By-product-Cellulose HDPE Coupling agent Composite Mechanical and rheological properties

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The importance of functional diversity in the stability of Mediterranean shrubland communities after the impact of extreme climatic events

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Journal of Plant Ecology 2017年第2期10卷 281-293页

作者： Enrique Gde la Riva Francisco Lloret Ignacio MPérez-Ramos Teodoro Marañón Sandra Saura-Mas Ricardo Díaz-Delgado Rafael Villar Area de Ecología Facultad de CienciasUniversidad de Cordoba.14071 CordobaSpain CREAF Cerdanyola del Vallés08193 BarcelonaSpain Unitat d’Ecologia Dept.Biologia AnimalBiologia Vegetal i EcologiaUniversitat Autònoma BarcelonaEdifici CCampus UAB08193Cerdanyola del VallèsBarcelonaSpain IRNAS CSICAv.Reina Mercedes 10PO Box 1052.41080 SevillaSpain Estación Biológica de Doñana CSIC.c/Americo Vespucios/nIsla de la Cartuja.41092 SevillaSpain

Aims Extreme climatic events may have important consequences for plant community structure and *** 2005,a severe drought together with a cold winter promoted extensive damage and mortal-ity in shrubland communities of southwest Spain(Doñana National Park).Here,we aim to identify the mechanisms underlying commu-nity stability(resistance and resilience)in response to this extreme climatic event,considering changes in the functional structure of these *** We used a trait-based approach,quantifying variations in 10 func-tional traits at the community level(community weighted means,CWM)and the functional diversity(functional richness,evenness and divergence)in 18 plots at three different times:predating the climatic event(estimated from the sum of the live and dead volume of each species in 2007),and 2 and 8 years after the 2005 *** also quantified the differences in functional traits and functional diversity between adult and recruit stages,which allowed us to bet-ter understand the contribution of the recruitment to the mainte-nance of the functional structure and diversity of the *** Findings Communities with higher functional divergence before the cli-matic event maintained nearly constant their levels of functional divergence 8 years after,but they were more prone to changes in species *** resistance in terms of vegeta-tion cover was positively correlated with root dry matter content,whereas community resilience was positively correlated with leaf chlorophyll(LChl).We also found that some values(weighted means)of functional community traits(such as root dry matter con-tent and LChl)had increased 2 years after the event,returning to the pre-event conditions after 8 *** addition,there was hardly any establishment of new species in the community and the recruits did not make substantial differences to the community functional *** seed mass differed significantly between the adult and se

关键词： climate change Doñana drought functional trait recruitment resilience resistance

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Functional genomic approach to the study of biodiversitywithin Trichoderma

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浙江大学学报(农业与生命科学版) 2004年第4期30卷 453-453页

作者： Monte E Hermosa M R González F J Rey M Cardoza R E Gutiérrez S Delgado Jarana J Llobell A Centro. Hispano-Luso de Investigaciones Agrarias University of Salamanca Plaza Doctores de la Reina s/n 37007 Salamanca Spain Newbiotechnic S.A. (NBT) Seville Spain University of León Campus of Ponferrada Superior and Technical Universitary School of Agricultural Engineers 24400 Ponferrada. Spain IBVF isla de la Cartuja CSIC/University of Seville Seville Spain

Trichoderma is a fungal genus of great and demonstrable biotechnological value, but its genome is poorly surveyed compared with other model microorganisms. Due to their ubiquity and rapid substrate colonization, Trichoderma species have been widely used as biocontrol organisms for agriculture, and their enzyme systems are widely used in industry. Therefore, there is a clear interest to explore beyond the phenotype to exploit the underlying genetic systems using functional genomics tools. The great diversity of species within the Trichoderma genus, the absence of optimized systems for its exploration, and the great variety of genes expressed under a wide range of ambient conditions are the main challenges to consider when starting a comprehensive functional genomics study. An initial project started by three Spanish groups has been extended into the project TRICHOEST, funded by the EU (FP5, QLRT-2001-02032) to target the transcriptome analysis of selected Trichoderma strains with biocontrol potential, in conditions related to antagonism, nutrient stress and plant interactions. Once specific conditions were defined, cDNA libraries were produced and used for EST sequencing. Nine strains from seven Trichoderma species have been considered in this study and an important amount of gene sequence data has been generated, analyzed and used to compare the gene expression in different strains. In parallel to sequencing, genomic expression studies were carried out by means of macro-arrays to identify genes expressed in specific conditions. In silico analysis of DNA sequencing data together with macro-array expression results have lead to a selection based on the potential use of the gene sequences. The selected clone sequences were completed and cloned in appropriate vectors to initiate functional analysis by means of expression studies in homologous and heterologous systems.

关键词： functional genomics proteomics Trichoest

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Does Making Method of Alginate Hydrogel Influence the Chondrogenic Differentiation of Human Mesenchymal Stem Cells?

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Engineering（科研） 2012年第10期4卷 110-113页

作者： Jessica Schiavi Naceur Charif Natalia de isla Daniele Bensoussan Jean-Francois Stoltz Nadia Benkirane-Jessel Celine Huselstein INSERM-UMR Faculty of medicineStrasbourg UniversityStrasbourgFrance Universitede Lorraine CNRS-UMR–Campus Sante–BiopoleFaculty of medicineLorraine UniversityVandouvre-les-NancyFrance

To overcome cartilage injury, strategies have been developed in the last few years based on tissue engineering to rebuild the defects. Cartilage engineering is principally based on three main biological factors: cells (native cells (chondrocytes) or a more primitive ones as mesenchymal stem cells), scaffolds and functionalization factors (growth factors, mechanical stimulation and/or hypoxia). Cartilage tissue engineering strategies generally result in homogeneous tissue structures with little resemblance to native zonal organization of articular cartilage. The main objective of our work concerns the buildup of complex biomaterials aimed at reconstructing biological tissue with three dimensional cells construction for mimicking cartilage architecture. Our strategy is based on structures formation by simple and progressive spraying of mixed alginate hydrogel and human mesenchymal stem cells (hMSC). In this work, the comportment of cells and more precisely their chondrogenic differentiation potential is compared to a traditional making process: the mold. We report here that spraying method allowed to product a scaffold with hMSC that confer a favorable environment for neocartilage construction.

关键词： Component: Cartilage Tissue Engineering Sodium Alginate Sprayed method Molded Method

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Recent surface marine sediments of Cocos island in Costa Rica

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International Journal of Sediment Research 2014年第1期29卷 59-72页

作者： Jeffrey A.SIBAJA-CORDERO Jesús S.TRONCOSO Eddy GóMEZ-RAMíREZ Escuela de Biología&Centro de Investigación en Ciencias del Mary Limnología (CIMAR) Universidad de Costa Rica Dr.grad.by Departamento de Ecología y Biología Animal Facultad de Ciencias del MarUniversidad de Vigo Departamento de Ecología y Biología Animal Facultad de Ciencias del MarUniversidad de VigoCampus Lagoas Marcosende Centro de Investigación en Ciencias del Mary Limnología(CIMAR) Universidad de Costa RicaSan Pedro 115012 060 San JoséCosta Rica Dr.(Cand).Departamento de Biología Facultad de Ciencias del Mary AmbientalesUniversidad de Cádiz

Subtidal sediments of isla del Coco(Cocos island),Costa Rica were described in their grain size,sorting,organic matter,and carbonates from 27 dredge samples(3-75 m),collected in April *** organic matter range between 1.37-3.31%and carbonates presented a mean of 74±17%.The sorting was moderately or *** grain size ranged between *** pattern is that sediment change from inner to mouth of *** and gravel fractions increased offshore and organic matter have high values inner the *** of vegetal debris and mud was from the rivers of this island covered with rain and cloud forest.

关键词： Sand bottom Sorting Organic matter Carbonates isla del Coco

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First record of Odontaster penicillatus populations(Philippi,1870)(Echinodermata:Asteroidea)in the Atacama and Antofagasta regions,Chile(Southeast Pacific)

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Acta Oceanologica Sinica 2022年第12期41卷 152-155页

作者： Leonardo Campos Fernando Berrios Brenda BHermosillo-Núñez Marco Ortiz Departamento de Ciencias Acuáticas y Ambientales Universidad de Antofagasta ChileAntofagasta 1240000Chile Centro de Investigaciones Costeras Universidad de Atacama(CIC-UDA) Avenida Copayapu 485Copiapó1530000Chile Laboratorio de Modelamiento de Sistemas Ecológicos Complejos(LAMSEC) Instituto AntofagastaUniversidad de AntofagastaAntofagasta 1240000Chile Instituto de Ciencias Naturales AvH Facultad de Ciencias del Mar y Recursos BiológicosUniversidad de AntofagastaAntofagasta 1240000Chile Centro de Investigación y Estudios Avanzados del Maule Vicerrectoría de Investigación y PosgradoUniversidad Católica Del MauleCampus San MiguelTalca 3480094Chile

We report for the first time the presence of local populations of the starfish Odontaster penicillatus in the regions of Atacama and Antofagasta,*** finding indicates an extension of the distribution limit of 500 km with respect to the last observation made in 2007 in isla Grande de Atacama.A total of 121 specimens of *** were recorded at depths of between 8 m and 24 *** were associated with rocky substrate and with different species of barnacles,sponges and *** presence of *** expands the knowledge of the benthic biodiversity of the region,and the development of studies on its ecological importance will be promoted.

关键词： Odontaster penicillatus new record Antofagasta Atacama South Pacific Ocean

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Non-Invasive Second Harmonic Generation (SHG) in Macroscopy (MacroSHG) as Bio-Diagnosis to Image Collagen Network Organization in Extracellular Matrix

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Engineering（科研） 2014年第8期6卷 485-490页

作者： Dominique Dumas Elisabeth Werkmeister Sebastien Hupont Céline Huselstein Natalia De isla Marthe Rousseau Patrick Menu Didier Mainard Ingénierie Moléculaire et Thérapeutique (CNRS FR 3209) Plate Forme d’Imagerie Cellulaire et Tissulaire PTIBC-IBISA NANCY Nancy France Plate-Forme Microscopie-Imagerie-Cytométrie du campus Pasteur Lille (MICPaL) IFR 142 Institut Pasteur de Lille Institut de Biologie de Lille Lille France Universite de Lorraine Physiopathologie Pharmacologie et Ingénierie Articulaires (IMOPA CNRS 7365) Nancy France Universite de Lorraine Physiopathologie Pharmacologie et Ingénierie Articulaires (IMOPA CNRS 7365) Nancy France Ingénierie Moléculaire et Thérapeutique (CNRS FR 3209) Plate Forme d’Imagerie Cellulaire et Tissulaire PTIBC-IBISA NANCY Nancy France

In this work, we have considered a new multimodality imaging for macroscopy based on Second Harmonic Generation (SHG) method to monitor invasivelessly the matrix collagen. As the triple helicoidally structure of collagen molecules appearing as not centrosymetric, very organized and spatially oriented, collagen fibrils give rise to a very strong SHG signal and can be imaged without any exogenous dye. To integrate a multidimensional scale with a large field of view (non-sliced samples), we have adapted and validated an instrumental coupling between a two photon excitation laser and a macroscope to collect cartography of SHG signal. We introduced an index (F-SHG) based on decay time response measured by TCSPC for respectively Fluorescence (F) and Second Harmonic Generation (SHG) values. For various sample where protein collagen is the major component of extracellular matrix (vessel, skin, carotide vessel, rat femoral head cartilage, mouse tumor, human wharton’s jelly and rat tendon) or not (nacre), we compared the index distribution obtained with MacroSHG. In this work, we showed for the first time that multiscale large field imaging (Macroscopy) combined to Multimodality approaches (SHG-TCSPC) could be an innovative and non-invasive technique to detect and identify some biological interest molecules (collagen) in biomedical topics.

关键词： Multiphoton Macroscopy Second Harmonic Generation Collagen Extracellular Matrix

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