SENSITIVITY ANALYSIS OF TRACK VIBRATIONS DUE TO VERTICAL STIFFNESS VARIATION IN HIGH-SPEED RAILWAYS

High speed trains, when crossing regions with abrupt changes in vertical stiffness of the track and/or subsoil, may generate excessive ground and track vibrations. There is an urgent need for specific analyses of this problem so as to allow reliable esimates of vibration amplitude. Full understanding of these phenomena will lead to new construction solutions and mitigation of undesirable features. In this paper analytical transient solutions of dynamic response of one-dimensional systems with sudden change of foundation stiffness are derived. Results are expressed in terms of vertical displacement. Sensitivity analysis of the response amplitude is also performed. The analytical expressions presented herein, to the authors’ knowledge, have not been published yet. Although related to one-dimensional cases, they can give useful insight into the problem. Nevertheless, in order to obtain realistic response, vehicle- rail interaction cannot be omitted. Results and conclusions are confirmed using general purpose commercial software ANSYS. In conclusion, this work contributes to a better understanding of the additional vibration phenomenon due to vertical stiffness variation, permitting better control of the train velocity and optimization of the track design

Session D2: Coimbra Fishway: Restoring Connectivity in River Mondego

Abstract: River Mondego is the largest Portuguese river with its basin entirely within national territory. The Açude-Ponte dam was built in Mondego in the 80’s, along with three other large dams to mitigate floods and to allow the integrated use of river basin water resources for hydroelectric power generation, public supply, industry and irrigation. Considering the river importance for several fish species, namely sea-lamprey and shad, a fishway was constructed. Several structural and hydraulic problems soon revealed that this fishway was inefficient therefore this dam became the first impassable obstacle in the River Mondego. In 2011, after several years of biological and hydraulic monitoring, and once the reasons for the fishway inefficiency were perfectly identified, a vertical-slot fishway was built to restore river connectivity. The efficiency and effectiveness of the Coimbra Fishway has been studied since 2012 using several monitoring techniques (visual counts, biotelemetry techniques and CPUE abundance with electrofishing). Monitoring results show that several autochthonous species use the fishway, including the diadromous sea-lamprey, allis and twaite shad and European-eel. More than 1,500.000 fish have used the fishway during the upstream or downstream migration. PIT telemetry has shown an efficiency of 30% for Petromyzon marinus and 14% for Luciobarbus bocagei. Pre and post fishway construction electrofishing monitoring shows improvements in sealamprey larvae abundance both upstream and downstream from the Açude-Ponte dam. Coimbra Fishway project is improving fish migration in River Mondego, but it’s also an integrated project involving other important aspects such as fisheries and river basin management and environmental education. Changes in exploitation regimes of upstream hydropower dams and in the Açude-Ponte are also planned to increase the fishway efficiency. Finally, several activities have been carried out in association with this project to raise public awareness regarding environmental issues, particularly those related with river longitudinal continuity

Application of Hydralcoholic extracts of Salvia officinalis and Salvia elegans in cosmetic formulations

Salvia Officinalis and Salvia elegans are shrubs belonging to the genus Salvia, family of the Lamiaceae, easily found in the Mediterranean region, Mexico and Guatemala respectively. In addition to traditional medicine, S. officinalis is of great importance to the pharmaceutical, cosmetic and food industries. (Cuvelier et al., 1996; Martins et al., 1998 in Povh & Ono, 2008), whereas S. elegans is known in cooking as a preservative or flavoring (Pereira et al., 2014). Natural products have increased, discovering new therapeutic indications, meeting the demands of the world population taking into account their quality and safety. In this study, the focus is on phenolic compounds as an active ingredient in an anti-age formulation. Carbopol and methylcellulose-based gel was prepared together with Salvia officinalis and Salvia elegans hydroalcoholic extract as their active principle by performing physical-chemical, organoleptic gel stability tests and performing the eye irritability test (HET-CAM), beyond performing hydrodistillation at Clevenger. The essential oil was extracted by steam entrainment, yielding after 3 hours. The hydroalcoholic principle gels were prepared at three different concentrations, 1.25; 2.5 and 5%, and then tests were performed to evaluate the stability of the product obtained as: light cycles, freeze / thaw cycles, centrifugation and vortexing, pH determination, microbiological analysis and HET-CAM test. According to the results, the pH test showed changes for the two plants containing their gels but never exceeding the ideal limits for the skin, even when exposed to the light cycle, only the color that was changed after 15 days, in the different concentrations. In freezing / thawing tests for Salvia officinalis the methylcellulose gel did not change, the carbopol gel did change the appearance but small changes are acceptable as the samples are subjected to extreme heat (45 ° C) and cold temperatures. (-20 ° C). For Salvia elegans there was a change in appearance and pH, which was also changed in the methylcellulose gel. All pH changes do not lead to considerer the gel as inappropriate. In microbiological tests the oils have a moderate effect, while in the other tests there were no changes. Centrifugation and vortex tests were performed for both gels using both plants with only hydroalcoholic extract at different concentrations and there was no change. All gels had an alcoholic odor during the tests. It can be concluded that carbopol and methylcellulose gel do not appear to have any detrimental effects when used in this cosmetic product, even when used in conjunction with plant essential oil and can therefore be used as an anti-aging formulation. However, the development of more tests is extremely important as toxicity tests, but stability tests already have promising results.The authors thank the Science and Technology Foundation (FCT, Portugal) and the ERDF under the PT2020 Program for their financial support to CIMO UID/AGR/0069012019info:eu-repo/semantics/publishedVersio

Application of Hydralcoholic extracts of Salvia officinalis and Salvia elegans in cosmetic formulations

Salvia Officinalis and Salvia elegans are shrubs belonging to the genus Salvia, family of the Lamiaceae, easily found in the Mediterranean region, Mexico and Guatemala respectively. In addition to traditional medicine, S. officinalis is of great importance to the pharmaceutical, cosmetic and food industries. (Cuvelier et al., 1996; Martins et al., 1998 in Povh & Ono, 2008), whereas S. elegans is known in cooking as a preservative or flavoring (Pereira et al., 2014). Natural products have increased, discovering new therapeutic indications, meeting the demands of the world population taking into account their quality and safety. In this study, the focus is on phenolic compounds as an active ingredient in an anti-age formulation. Carbopol and methylcellulose-based gel was prepared together with Salvia officinalis and Salvia elegans hydroalcoholic extract as their active principle by performing physical-chemical, organoleptic gel stability tests and performing the eye irritability test (HET-CAM), beyond performing hydrodistillation at Clevenger. The essential oil was extracted by steam entrainment, yielding after 3 hours. The hydroalcoholic principle gels were prepared at three different concentrations, 1.25; 2.5 and 5%, and then tests were performed to evaluate the stability of the product obtained as: light cycles, freeze / thaw cycles, centrifugation and vortexing, pH determination, microbiological analysis and HET-CAM test. According to the results, the pH test showed changes for the two plants containing their gels but never exceeding the ideal limits for the skin, even when exposed to the light cycle, only the color that was changed after 15 days, in the different concentrations. In freezing / thawing tests for Salvia officinalis the methylcellulose gel did not change, the carbopol gel did change the appearance but small changes are acceptable as the samples are subjected to extreme heat (45 ° C) and cold temperatures. (-20 ° C). For Salvia elegans there was a change in appearance and pH, which was also changed in the methylcellulose gel. All pH changes do not lead to considerer the gel as inappropriate. In microbiological tests the oils have a moderate effect, while in the other tests there were no changes. Centrifugation and vortex tests were performed for both gels using both plants with only hydroalcoholic extract at different concentrations and there was no change. All gels had an alcoholic odor during the tests. It can be concluded that carbopol and methylcellulose gel do not appear to have any detrimental effects when used in this cosmetic product, even when used in conjunction with plant essential oil and can therefore be used as an anti-aging formulation. However, the development of more tests is extremely important as toxicity tests, but stability tests already have promising results.The authors thank the Science and Technology Foundation (FCT, Portugal) and the ERDF under the PT2020 Program for their financial support to CIMO (UID /AGR /00690/2019)info:eu-repo/semantics/publishedVersio

Desarrollo y estabilidad de un gel antienvejecimiento con extracto hidroalcohólico de Salvia SP.

Introduction: The incessant search for products from nature to apply in the search for treatment, cure or even the well-being associated with the aesthetics itself, has strongly collaborated to deepen the area of study and knowledge, so as to meet the demands of the world population. Objectives: This work aimed at the development and evaluation of the stability of two gels formulations (carbopol and methylcellulose) from the incorporation of the essential oils of the species S. officinalis and S. elegans and their hydroalcoholic extract. Methods: Physicochemical stability, organoleptic gel tests, eye irritability test (HET-CAM test) and Clevenger hydrodistillation were performed to determine the oil yield and to use them as a natural preservative in the gels. Results: As significant results we have: In light cycle tests there was only a color change after 15 days. In freeze / thaw tests there was a change in carbopol gel for S. officinalis in appearance and for S. elegans in pH and appearance, whereas in methylcellulose gel in S. elegans there was only change in pH. The accelerated stability test showed alteration for both gels, in the samples containing carbopol gel there was color change and evaporation of part of the gel, while in methylcellulose the complete dehydration. Conclusions: The samples of the gels with hydroalcoholic extract of S. elegans and S. officinalis in concentrations of 5%, 2.5% and 1.25% obtained good stability according to the tests to which they were submit.Introdução: A busca incessante de produtos vindo da natureza para aplicar na procura do tratamento, cura ou até mesmo o bem-estar associado à própria estética, tem colaborado fortemente para aprofundar a área de estudo e conhecimento em cosméticos, para assim poder atender às exigências da população mundial. Objetivos: Este trabalho visou o desenvolvimento e avaliação da estabilidade de formulações de dois géis (carbopol e metilcelulose) a partir da incorporação dos óleos essenciais das espécies S. officinalis e S. elegans e o extrato hidroalcoólico das mesmas sendo este último, utilizado como princípio ativo. Métodos: Realizaram-se testes de estabilidade físico-química, organoléptica dos géis, teste de irritabilidade ocular (teste HET-CAM) e hidrodestilação em Clevenger para assim recolher o rendimento dos óleos e utilizá-los também como conservante natural nos géis. Resultados: Como resultados significativos obtiveram-se: testes de ciclo de luz houve apenas a alteração da cor após 15 dias. Nos testes de congelamento/descongelamento houve mudança no gel de carbopol para S. officinalis no aspecto e para S. elegans no valor de pH e aspecto, no gel de metilcelulose em S. elegans houve apenas alteração no valor de pH. O teste de estabilidade acelerada houve alteração para os dois géis, nas amostras contendo o gel de carbopol houve mudança de coloração e desidratação parcial do gel, no de metilcelulose ocorreu a completa desidratação. Conclusões: As amostras dos géis com extrato hidroalcoólico de S. elegans e S. officinalis nas concentrações de 5%, 2,5% e 1,25% obtiveram boa estabilidade de acordo com os testes a que foram submetidos.Introducción: La búsqueda incesante de productos de la naturaleza para aplicar en la búsqueda de tratamiento, cura o incluso el bienestar asociado con la estética en sí, ha colaborado fuertemente para profundizar el área de estudio y conocimiento, a fin de satisfacer las demandas de la población mundial. Objetivos: Este trabajo tuvo como objetivo el desarrollo y evaluación de la estabilidad de dos formulaciones de geles (carbopol y metilcelulosa) a partir de la incorporación de los aceites esenciales de las especies S. officinalis y S. elegans y su extracto hidroalcohólico. Métodos: La estabilidad fisicoquímica, las pruebas de gel organoléptico, la prueba de irritabilidad ocular (prueba HET-CAM) y la hidrodestilación de Clevenger se realizaron para recolectar el rendimiento de aceite y también para usarlos como conservantes naturales en los geles. Resultados: Como resultados significativos tenemos: En las pruebas de ciclo de luz solo hubo un cambio de color después de 15 días. En las pruebas de congelación / descongelación hubo un cambio en la apariencia del gel de carbopol para S. officinalis y para S. elegans en pH y apariencia, mientras que en el gel de metilcelulosa en S. elegans solo hubo cambio en el pH. La prueba de estabilidad acelerada mostró alteración para ambos geles, en las muestras que contenían gel de carbopol hubo cambio de color y evaporación de parte del gel, mientras que en la metilcelulosa la deshidratación completa. Conclusiones: Las muestras de los geles con extracto hidroalcohólico de S. elegans y S. officinalis en concentraciones de 5%, 2.5% y 1.25% obtuvieron buena estabilidad de acuerdo con las pruebas a las que fueron sometidos.The authors would like to thank the Foundation for Science and Technology (FCT, Portugal) and the ERDF under the PT2020 Program for financial support to CIMO UID/AGR/00690/2019info:eu-repo/semantics/publishedVersio

Tensor-Based Methods for Blind Spatial Signature Estimation in Multidimensional Sensor Arrays

The estimation of spatial signatures and spatial frequencies is crucial for several practical applications such as radar, sonar, and wireless communications. In this paper, we propose two generalized iterative estimation algorithms to the case in which a multidimensional (R-D) sensor array is used at the receiver. The first tensor-based algorithm is an R-D blind spatial signature estimator that operates in scenarios where the source’s covariance matrix is nondiagonal and unknown. The second tensor-based algorithm is formulated for the case in which the sources are uncorrelated and exploits the dual-symmetry of the covariance tensor. Additionally, a new tensor-based formulation is proposed for an L-shaped array configuration. Simulation results show that our proposed schemes outperform the state-of-the-art matrix-based and tensor-based techniques

Herbage Intake, Methane Emissions and Animal Performance of Steers Grazing Dwarf Elephant Grass with or without Access to \u3cem\u3eArachis pintoi\u3c/em\u3e Pastures

The inclusion of legumes in diets based on grass has nutritional benefits due to ingestive and digestive interactions (Niderkorn and Baumont 2009). Moreover, it is speculated that tropical legumes can contribute to reducing the emission of greenhouse gases (GHG) compared to diets exclusively composed of grasses (Archimède et al. 2011). However, under grazing conditions, these advantages are not always possible to obtain. This occurs when the spatial distribution of sward grasses impose limitations on access to legumes by grazing animals (Solomon et al. 2011). This can be the case, for example, when legumes are overlapped by the leaves of a tufted tall grass, as dwarf elephant grass (Crestani et al. 2013). Considering that management strategies for increasing legumes in the diet of grazing animals should be better studied and data on enteric methane emitted by ruminants eating tropical forages are scarce, the aim of this work was to evaluate the effect of access to an exclusive area of peanuts (Arachis pintoi cv. Amarillo) for cattle grazing dwarf elephant grass (Pennisetum purpureum cv. BRS Kurumi) on herbage intake, animal performance and enteric methane emission

Vibrações associadas à variação rápida da rigidez da via férrea por acção de carga móvel

A variação rápida da rigidez das vias férreas, quer devido a mudança de solução estrutural, quer devido a alteração das condições geotécnicas pode induzir vibrações de amplitude excessiva à passagem de comboios de alta velocidade. Este comportamento causa desgaste da via. Nesta comunicação abordam-se aspectos de modelação e análise do problema. A contribuição consiste em desenvolvimento das soluções analíticas transientes de modelos simplificados em que a alteração de rigidez é implementada de duas formas. O primeiro caso corresponde à existência de uma rigidez adicional localizada e o segundo caso representa a passagem entre duas zonas de rigidez constante

Epigenetic reprogramming by TET enzymes impacts co-transcriptional R-loops

PTDC/BIA-MOL/30438/2017 PTDC/MED-OUT/4301/2020 RiboMed 857119 PD/BD/128292/2017 LCF/PR/HP21/52310016 PTDC/BIA-MOL/6624/2020 PTDC/MED-ONC/7864/2020DNA oxidation by ten-eleven translocation (TET) family enzymes is essential for epigenetic reprogramming. The conversion of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) initiates developmental and cell-type-specific transcriptional programs through mechanisms that include changes in the chromatin structure. Here, we show that the presence of 5hmC in the transcribed gene promotes the annealing of the nascent RNA to the template DNA strand, leading to the formation of an R-loop. Depletion of TET enzymes reduced global R-loops in the absence of gene expression changes, whereas CRISPR-mediated tethering of TET to an active gene promoted the formation of R-loops. The genome-wide distribution of 5hmC and R-loops shows a positive correlation in mouse and human stem cells and overlap in half of all active genes. Moreover, R-loop resolution leads to differential expression of a subset of genes that are involved in crucial events during stem cell proliferation. Altogether, our data reveal that epigenetic reprogramming via TET activity promotes co-transcriptional R-loop formation, disclosing new mechanisms of gene expression regulation.publishersversionpublishe