446 research outputs found

    Relatório de Consultadoria Técnico-Científico INNEA-Alternativas Biotecnológicas Valladolid, Espanha

    Get PDF
    Entre os dias 30 de janeiro e 4 de fevereiro de 2018 foi realizada uma consultadoria técnico-científica a empresa espanhola INNEA Alternativas Biotecnológicas, com sede social na cidade de Valladolid, Espanha. Esta empresa consta de um laboratório de cultura in vitro de espécies lenhosas na localidade de Dueñas, Palencia, onde efetivamente decorreram os trabalhos. O objetivo da visita foi prestar um serviço de consultadoria na cultura in vitro de espécies lenhosas de interesse comercial para esta empresa espanhola, particularmente na micropropagação do pinheiro manso (Pinus pinea L.). O convite foi efetuado pela experiência que a equipe da Universidade de Évora formada por formada por docentes do Departamento de Biologia (Professores Amely Zavattieri, Celeste Santos Silva, Luís Silva Dias, Paulo de Oliveira e Isabel Pereira† ) e do Departamento de Química (Professores Ana Teresa Caldeira, Rosário Martins, Dora Teixeira), dos aluno de doutoramento Rogério Louro, dos doutores Carla Ragonezi e Mário Rui Castro, técnicos superiores do Departamento de Biologia (Otília Miralto e Elsa ganhão) e consultora externa Krystyna Klimaszewska do Forest Service, Canada, possuem na organogénese de pinheiro manso a partir de cotilédones de sementes maturas e a micorrização in vitro com fungos ectomicorrízicos. Estes trabalhos que decorreram por mais de uma década, contaram com a dedicação de uma numerosa equipa de investigação. Entre outros motivos, o objeto da visita foi também falar da patente a as suas possibilidades de aplicação comercial. O nosso sistema de co-cultura foi patenteado (PT 105239, INPI) pelo grande interesse para aplicação entre as co-culturas plantas-fungos e para a realização de diversos estudos bioquímicos das relações plantas simbióticas, esta patente recebeu reconhecimento internacional, em este caso particular foi um convite para realizar uma consultadoria numa empresa do setor da produção de plantas

    Numerical Modeling of Damage Tolerant Biological Material

    Get PDF
    Biomineralized materials have the ability to employ high volume fraction of modest and brittle materials and still exhibit surprising mechanical performance. Decoding the structure-function relationship of these materials is a challenging task that requires knowledge about the actual loading and environmental conditions of the material in their natural habitat, as well as a complete characterization of their constituents and hierarchical ultrastructure through the use of modern tools such as in-situ electron microscopy, small-scale mechanical testing capabilities, prototyping, and advanced numerical models. In turn, this provides the necessary tools for the design and fabrication of biomimetic materials with remarkable properties. In this work, we will review some of our research activities covering the numerical aspects of fracture and damage in naturally occurring and biomimetic materials, including biomineralized materials found in hyper-mineralized exosqueleton of mantis shrimps. In our approach, we adopt a finite element methodology that uses a cohesive approach to brittle and quasi-brittle fracture in the mineral.Facultad de Ingenierí

    Crystalline Cellulose – Atomistic Modeling Toolkit

    Get PDF
    Nature has created efficient strategies to make materials with hierarchical internal structure that often exhibit exceptional mechanical properties. One such example is found in cellulose, in fact it is eight times stronger than stainless steel and advantage is that cellulose incredibly cheap, because processing is obtained from purified wood pulp (it is environmental friendly). The most prevalent modeling technique to study the fundamental mechanical behavior of the crystalline cellulose has been Molecular Dynamics (MD). As a predictive tool, MD allows us to study the behavior of crystalline cellulose at the atomic level, and as such, it accurately predicts the crystalline structure, covalent bonds and non-bonded interactions. State-of-the-art in-situ electron microscopy and atomic force microscopy experimental techniques can provide rich information about the structure and mechanics of these materials as well. However, interpretation of this experimental data requires the combination with modeling. Current efforts are focused on the development of an atomistic simulation toolkit that will allow us to run MD simulations to study the nonlinear structural behavior of cellulose chains and their interactions in crystalline cellulose

    Numerical Modeling of Damage Tolerant Biological Material

    Get PDF
    Biomineralized materials have the ability to employ high volume fraction of modest and brittle materials and still exhibit surprising mechanical performance. Decoding the structure-function relationship of these materials is a challenging task that requires knowledge about the actual loading and environmental conditions of the material in their natural habitat, as well as a complete characterization of their constituents and hierarchical ultrastructure through the use of modern tools such as in-situ electron microscopy, small-scale mechanical testing capabilities, prototyping, and advanced numerical models. In turn, this provides the necessary tools for the design and fabrication of biomimetic materials with remarkable properties. In this work, we will review some of our research activities covering the numerical aspects of fracture and damage in naturally occurring and biomimetic materials, including biomineralized materials found in hyper-mineralized exosqueleton of mantis shrimps. In our approach, we adopt a finite element methodology that uses a cohesive approach to brittle and quasi-brittle fracture in the mineral.Facultad de Ingenierí

    Histological Studies of Mycorrhized Roots and Mycorrhizal-Like-Structures in Pine Roots

    Get PDF
    Several studies have shown the potential of using Ectomycorrhizal (ECM) fungi in conifer micropropagation to overcome the cessation of adventitious root development. In vitro inoculation promotes the re-growth of the root system induced previously by auxin treatments, facilitating acclimation and diminishing the losses of plants because of a weak root system that is incapable of water and nutrient absorption. During a series of mycorrhization experiments, cryostat and ultrafine cuts were used to study the morpho-histological transformation of the symbiotic roots. To obtain cryostat cuts from pine roots a method frequently used for animal tissue was adopted. Molecular methods allowed fungi identification in all the mycorrhization phases and in the acclimation of derived plants. Mycorrhizal-like-structures derived from in vitro culture and axenic liquid cultures of roots were microscopically analyzed and compare with mycorrhizal roots

    Mechanics of CNC Nanofilm

    Get PDF
    In the past decade, many researchers have studied mechanical properties of polymer reinforced nanocomposites to understand and improve the performance of materials. In this research, we would develop a tool that would conduct a mechanical test on structures of a nanocomposite called Crystalline Nano Cellulose. Crystalline Nano Cellulose (CNC) is a strong and natural molecular structure that we could obtain from processing a regular cellulose cell we could obtain from ordinary plants through acid hydrolysis. The mechanical test on these structures of CNC would be able to provide information about the type of failure and the effect of length and arrangement of CNC structures on the mechanical properties. The main goal to the research is to evaluate the effect of CNC aspect ratio (length / width), the effect of angular distribution and the effect of microstructure on the mechanical properties. A tool would be built on nanoHUB that used Python as the programming language and Rappture as the GUI designer. The tool would accept user’s desired molecule length, the variance of the length, angular alignment of the molecules and variance of the angle values. In addition, the tool would accept these parameters to produce a visualization of the structure specified, run a mechanical test on the structure and provide a graphical feedback. The results that could be expected from the tool is a visualization of both the initial structure and simulation of the test on the structure. A series of feedback graph and data file of the test

    Development of a new NanoHUB Simulation Tool: Coarse graining of Crystalline Nano-Cellulose.

    Get PDF
    Crystalline Nano-cellulose (CNC) is a general molecular structure obtained from acid hydrolysis of native fiber. They are often very short (100 to 1000 manometers) and the mechanical properties of CNC varies depend on length scale. Due to defect formation of the structure, the mechanical properties of the material composed of such CNC may vary drastically. This study was to provide a numerical tool to integrate a few valid modules and to better understand the mechanical properties of CNC and the overall performance of the bio-inspired material composed of CNC. Our focus is mainly on two type of composite structure [1] bouligand structure which is found in mantis shrimp and [2] staggered structure based on bone structure. The Mechanical test on these structures can provide useful information on their type of failure and the effect of length and arrangement of CNC on overall mechanical properties. The tool was built with the instructions from nanohub using Rappture as GUI designer and Python as programming language. The key method is to generate the structure file using base structure of CNC and user input, then send shell command to computation and visualization package. Advanced data structures were used to ensure when duplicating in length formation of the cellulose doesn’t change. The results were almost the same with previous data obtain from a rather slow simulation. The simulation was 20% faster since the study optimized on structure generation. The computational package was external and it was where most of the time consumed. The overall performance of tool was sufficient to help fellow researchers and students to get a quick and accuracy mechanical property of a chosen CNC structure

    A new Late Triassic dipteridacean fern from the Paso Flores Formation, Neuquén Basin, Argentina

    Get PDF
    Sterile and fertile fronds of dipteridacean ferns from the Paso Flores Formation (late Norian–Rhaetian) at Cañadón de Pancho area, south of the Neuquén Province, Patagonia (Neuquén Basin), Argentina, are described. The Paso Flores Formation specimens comprise an interesting mixture of features showing a unique combination that does not fit in the diagnosis of any of the known fossil genera of Dipteridaceae. Characters such as the number and shape of primary segments in each rachial arm, the coalescence of the primary segments at the base of the frond, the distribution of sori and the number of sporangia per sori allow to differentiate the Paso Flores Formation specimens from the other genera of the family. The new genus and species, Patagoniapteris artabeae is proposed. The specimens share some frond morphological features with the fossil genera Clathropteris, Digitopteris, Thaumatopteris, Sewardalea and with some species of the Dictyophyllum, as well as the characteristic of the sori with the living species Dipteris lobbiana. The Paso Flores Formation environments developed on the western margin of Gondwana under seasonal temperate-warm and humid to sub-humid climates with a marine influence from the west. The Cañadón de Pancho assemblages are late Norian–Rhaetian in age, being the youngest fossil flora recorded from Argentinian Triassic basins to date.Fil: Gnaedinger, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Zavattieri, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentin

    A new taxa for dipteridaceae fronds from the paso flores formation, late triassic, Neuquén basin, Argentina

    Get PDF
    Steril and fertil fronds of dipteridacean ferns from the Paso Flores Formation (Norian) at Cañadón de Pancho area (Neuquén Basin, Argentina) are described. The morphological characteristics are: fanshaped fronds dissected in two equal and opposite rachial arms; each rachial arm bearing more than 18 primary segments. The primary segments fused up to 1/3 of the total length of the preserved lamina, and the remaining part is free, linear-lanceolate in shape, showing ondulate to deeply dissected lobes margins (less than 2/3 in length of the secondary vein). Primary and secondary veins simple, whereas tertiary veins dichotomized and forming irregularly polygonal areoles. Sori exindusiate, arranged in two regular rows on either side of the primary veins, as well as on both sides of the base of the secondary veins. Sori are round in outline, each sorus consists of 45-60 or more sporangia. Mixed maturation of sporangia. The annulus of the sporangia is oblique and complete. These specimens share some morphological features of the fronds with the fossil genera Clathropteris Brongniart, 1828, Digitopteris Pott and Bomfleur, 2018, Thaumatopteris Goeppert, 1841 and, with some species of the Dictyophyllum Lindley and Hutton, 1834 as well as in the character soral, with one the current species of Dipteris Reinwardt. The Paso Flores specimens comprise an interesting mixture of features showing a unique combination that do not fit in the circumscription of any of the known and most abundant genera of Dipteridaceae. Thus, these fossil dipterid fern fronds suggest that they belong to a new taxonomic entity.Fil: Gnaedinger, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Zavattieri, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina1° Reunión Virtual de Comunicaciones de la Asociación Paleontológica ArgentinaBuenos AiresArgentinaAsociación Paleontológica Argentin

    High fidelity model of a hook and loop fastener

    Get PDF
    There is a strong demand for new computational models that facilitate the design and the manufacturing process of hook and loop fastening products. Enhanced models can significantly shorten the design and production cycles by providing a quick turnaround time with minimal prototyping and testing. A set of experimental data was generated to characterize the mechanical behavior of polypropylene microfibers that are part of a multilayer material. A three dimensional micromechanical model was created to calculate the forces and the energy required for the attachment/detachment cycle using a Representative Hook and Loop Element model. The model accurately captures the mechanical behavior of the fastening joint given geometrical description and material information of the hook and loops
    corecore