2,167 research outputs found
Dimensional effects on magnetic properties of Fe-Si steels due to laser and mechanical cutting
Microstructural deterioration near the cut line and presence of residual stresses both affect the magnetic properties of cut parts. In this paper, the differences between microstructural deterioration resulting from mechanical and laser cutting as well as the sample size effects observed upon hysteresis will be discussed. It will be shown that the underlying mechanism for changes in magnetic properties due to mechanical cutting is distinct from that of laser cutting
Correlation between microstructure, texture, and magnetic induction in nonoriented electrical steels
Although it is well known that the magnetic induction of electrical steels at a given applied field critically depends on the microstructure and on the present crystallographic texture, there is still no quantitative model to describe this relation in the whole range of inductions. In this paper, the existing different models for the dependence of B-8, B-25, and B-50 on the texture intensities will be evaluated in detail. Finally, a more general model is proposed for the dependence of the magnetic induction at a given applied field as a function of the mean grain size, a texture related parameter and the Si content of the material
Spatial-temporal variation of leaf area index and brix in sugarcane
Os objetivos do trabalho foram estudar a variação espaço-temporal do índice de área foliar (IAF) e do teor de sólidos solúveis (Brix) na cana-de-açúcar, em Piracicaba (SP), em 2003 e 2004, utilizando a geoestatística, visando melhorar a simulação da interceptação da radiação solar principalmente no ajuste do coeficiente de extinção. Verificaram-se maiores valores do IAF no ciclo de crescimento da variedade SP 80-3280 em comparação com a RB 85 5156 obtendo valores máximos de 6,41 e 4,27 respectivamente, medidos em 14/1/2004 com grande variação espacial nas áreas analisadas, além de maiores valores do IAF e menores do Brix em locais com maior disponibilidade hídrica, indicativo de atraso da maturação. A única medida do Brix feita em 29/4/2004 das variedades SP 80-3280 e RB 85 5156 indicaram valores médios de 12,86 e 17,06 respectivamente, mostrando a precocidade da RB 85 5156. O uso de valores diários variáveis do coeficiente de extinção em modelos de cultura é recomendado, melhorando a simulação da interceptação da radiação solar, minimizando erros na estimativa da produtividade principalmente quando analisamos diferentes variedades de cana-de-açúcar.The goals of this work were to study the spatial-temporal variation of leaf area index (LAI) and soluble solids (Brix) in sugarcane cultived in Piracicaba, São Paulo State, in the years of 2003 and 2004. Geoestatistic methodology was used aiming improvement in the simulation of solar radiation interception, and specially adjustment of extinction coefficient. During growth cycle larger values of leaf area index were verified in variety SP 80-3280 than in RB 85 5156. Those values ranged from 6.41 to 4.27 respectively, and were measured in 1/14/2004, with large spatial variation. Higher values for LAI and smaller values for Brix were also observed under high water available, indicating a delay in maturation. The only Brix measurement performed in the varieties SP 80-3280 and RB 85 5156 on 4/29/2004 indicated average values of 12.86 and 17.06 respectively, demonstrating the precocity of RB 85 5156. The use of daily variable values of the extinction coefficient is recommended, improving the simulation of solar radiation interception, minimizing mistakes estimating the productivity when different sugarcane varieties were analyzed
Local arrangement of Fibronectin by myofibroblasts governs peripheral nuclear positioning in muscle cells
© 2018 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)Skeletal muscle cells (myofibers) are rod-shaped multinucleated cells surrounded by an extracellular matrix (ECM) basal lamina. In contrast to other cell types, nuclei in myofibers are positioned just below the plasma membrane at the cell periphery. Peripheral nuclear positioning occurs during myogenesis and is driven by myofibril crosslinking and contraction. Here we show that peripheral nuclear positioning is triggered by local accumulation of fibronectin secreted by myofibroblasts. We demonstrate that fibronectin via α5-integrin mediates peripheral nuclear positioning dependent on FAK and Src activation. Finally, we show that Cdc42, downstream of restricted fibronectin activation, is required for myofibril crosslinking but not myofibril contraction. Thus we identify that local activation of integrin by fibronectin secreted by myofibroblasts activates peripheral nuclear positioning in skeletal myofibers.info:eu-repo/semantics/publishedVersio
Geomorphological analysis of Castro de Laboreiro area (PNPG) with LiDAR data
Este trabalho apresenta os resultados da análise geomorfológica do relevo de Castro de
Laboreiro (Parque Nacional da Peneda-Gerês). A interpretação realizou-se com recurso a dados
topográficos de grande precisão vertical e horizontal (dados LiDAR) e fotografia aérea de elevada
resolução. Assim, foi possível identificar e diferenciar formas de relevo características da área, tais como:
relevos residuais, vales de fratura/falha, cones de dejeção/leques aluviais. Paralelamente, identificaramse
possíveis capturas fluviais com os respetivos cotovelos de captura e vales secos, assim como, a
definição de pequenas paleobacias endorreicas. Os dados morfológicos acentuam a influência da
fracturação/litologia nas formas de relevo desta área. Adicionalmente, demonstram a importância
destes dados para o avanço no conhecimento geomorfológico do PNPG
Modelo fisiológico para a estimativa da maturação em cana-de-açúcar
Sugarcane (Saccharum spp.) grows in different weather and management conditions which directly affect crop maturation. These conditions lead to the necessity of quantifying crop response to different stimuli for planning purposes. Forecast models for the quality of raw material are important tools in sugarcane farming, especially the forecast curve of sucrose accumulation in shoots. The goal of these models is to supply yield estimates during the crop cycle, aiming to characterize alternatives and to increase the efficacy for management and strategic decisions. The objective of this project was to develop empiric models capable of obtaining estimates of total recoverable sugar (TRS), for the varieties RB72454, SP81-3250 and SP80-1842 during the crop cycle, using reference data as the production factors. Sugarcane harvest results obtained in Piracicaba, State of São Paulo, Brazil were analyzed using the following parameters: maturation, stand age, type of soil, variety, flowering and management for the crops in the years 1998/99, 1999/00, 2000/01, 2001/02 and 2002/03. Models developed for these years were used to estimate TRS from the 2003/04 cropping season. All the forecast models for ratoon crops were significant indicating that they are an excellent tool to optimize agricultural planning.A cultura da cana-de-açúcar (Saccharum spp.) é submetida a diferentes condições ambientais e de manejo durante o seu desenvolvimento, o que afeta diretamente a maturação. Assim, surge a necessidade de se quantificar as respostas da cultura aos diferentes estímulos para fins de planejamento. Modelos de previsão da qualidade da matéria-prima tornam-se ferramentas importantes na lavoura canavieira, em especial a previsão da curva de acúmulo de sacarose nos colmos, objetivando suprir estimativas de rendimento ao longo da safra, visando à caracterização das alternativas de manejo, aumentando a eficácia das decisões gerenciais e estratégicas. Desenvolveram-se modelos empíricos capazes de obter estimativas de ATR - Açúcar Total Recuperável nas variedades RB72454, SP81-3250 e SP80-1842 ao longo da safra, utilizando dados referentes aos fatores de produção. Foram analisados os resultados de colheita realizados no município de Piracicaba - SP, dos anos safras 1998/99, 1999/00, 2000/01, 2001/02 e 2002/03 considerando a maturação, idade do canavial, solos, variedades, florescimento e manejo, utilizando-se de modelos estatísticos de estimativa da maturação para estimar a safra 2003/04. Todos os modelos de previsão para cana-soca mostraram-se significativos, sendo uma ótima ferramenta de auxílio para o planejamento agrícola otimizado.FAPES
Estimativa da maturação da cana-de-açúcar por meio de parâmetros edafoclimáticos
A cultura da cana-de-açúcar (Saccharum officinarum L.) é submetida durante o seu desenvolvimento a diferentes condições ambientais que afetam diretamente a maturação. Modelos de previsão da qualidade da matéria-prima são ferramentas importantes no gerenciamento da lavoura canavieira, pois permitem estimativas de rendimento ao longo da safra, o que aumenta a eficácia das decisões gerenciais e estratégicas. O objetivo deste trabalho foi desenvolver um modelo capaz de obter estimativas de Açúcar Total Recuperável (ATR), utilizando dados referentes aos fatores de produção como armazenamento de água no solo e graus-dias negativos. Para o teste dos modelos estatísticos de estimativa da qualidade da matéria-prima foi utilizado o banco de dados de uma usina açucareira com produções das safras 1999/2000, 2000/2001 e 2001/2002. O modelo de maturação para cana de ano mostrou-se significativo, com um coeficiente de determinação R² = 0,7049*. Na simulação não houve diferença entre os dados medidos e estimados (P < 0,05).Sugarcane (Saccharum officinarum L.) grows under different weather conditions directly affecting crop maturation. Raw material quality predicting models are important tools in sugarcane crop management; the goal of these models is to provide productivity estimates during harvesting, increasing the efficiency of strategical and administrative decisions. The objective of this work was developing a model to predict Total Recoverable Sugars (TRS) during harvesting, using data related to production factors such as soil water storage and negative degree-days. The database of a sugar mill for the crop seasons 1999/2000, 2000/2001 and 2001/2002 was analyzed, and statistical models were tested to estimate raw material. The maturity model for a one-year old sugarcane proved to be significant, with a coefficient of determination (R²) of 0.7049*. No differences were detected between measured and estimated data in the simulation (P < 0.05)
Dealing with the nucleus during cell migration
© 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).The position of the nucleus within cells is a key event during cell migration. The movement and positioning of the nucleus strongly impacts cell migration. Notably, the last two years largely contributed to emphasise the dynamicity of the nucleus-cytoskeleton interactions that occur during cell migration. Nuclei are under continuous tension from opposing intracellular forces and its tether to the cytoskeleton can be regulated at different levels. Interestingly, it was showed how nuclear positioning is highly related to cell function. In most migrating cells, including cancer cells, the nucleus can be the rate limiting step of cell migration and is placed away from the leading edge. By contrast, leukocytes position their nucleus close to the lamellipodia at the leading edge, and the nucleus contributes to drilling through the endothelium. Differences in cell migration in 2D versus 3D environments are also evident. The mechanisms and forces at play during nuclear positioning and translocation are clearly affected by the nature of the substrate. As such nuclear positioning during cell migration can vary between cell types and environments. In this review we aim to give an overview of the latest discoveries in the field revealing how nuclear positioning is tightly regulated, not only by intrinsic nuclear properties, such as deformability, nuclear envelope content or nucleus-cytoskeleton connectivity, but also by the microenvironment.This work was supported by the European Research Council, EMBO installation, LISBOA-01-0145-FEDER-007391, project cofunded by FEDER, through POR Lisboa 2020 — Programa Operacional Regional de Lisboa, Portugal 2020 and Fundação para a Ciência e a Tecnologia.info:eu-repo/semantics/publishedVersio
Modelo fisiológico para a estimativa da maturação em cana-de-açúcar
A cultura da cana-de-açúcar (Saccharum spp.) é submetida a diferentes condições ambientais e de manejo durante o seu desenvolvimento, o que afeta diretamente a maturação. Assim, surge a necessidade de se quantificar as respostas da cultura aos diferentes estímulos para fins de planejamento. Modelos de previsão da qualidade da matéria-prima tornam-se ferramentas importantes na lavoura canavieira, em especial a previsão da curva de acúmulo de sacarose nos colmos, objetivando suprir estimativas de rendimento ao longo da safra, visando à caracterização das alternativas de manejo, aumentando a eficácia das decisões gerenciais e estratégicas. Desenvolveram-se modelos empíricos capazes de obter estimativas de ATR - Açúcar Total Recuperável nas variedades RB72454, SP81-3250 e SP80-1842 ao longo da safra, utilizando dados referentes aos fatores de produção. Foram analisados os resultados de colheita realizados no município de Piracicaba - SP, dos anos safras 1998/99, 1999/00, 2000/01, 2001/02 e 2002/03 considerando a maturação, idade do canavial, solos, variedades, florescimento e manejo, utilizando-se de modelos estatísticos de estimativa da maturação para estimar a safra 2003/04. Todos os modelos de previsão para cana-soca mostraram-se significativos, sendo uma ótima ferramenta de auxílio para o planejamento agrícola otimizado.Sugarcane (Saccharum spp.) grows in different weather and management conditions which directly affect crop maturation. These conditions lead to the necessity of quantifying crop response to different stimuli for planning purposes. Forecast models for the quality of raw material are important tools in sugarcane farming, especially the forecast curve of sucrose accumulation in shoots. The goal of these models is to supply yield estimates during the crop cycle, aiming to characterize alternatives and to increase the efficacy for management and strategic decisions. The objective of this project was to develop empiric models capable of obtaining estimates of total recoverable sugar (TRS), for the varieties RB72454, SP81-3250 and SP80-1842 during the crop cycle, using reference data as the production factors. Sugarcane harvest results obtained in Piracicaba, State of São Paulo, Brazil were analyzed using the following parameters: maturation, stand age, type of soil, variety, flowering and management for the crops in the years 1998/99, 1999/00, 2000/01, 2001/02 and 2002/03. Models developed for these years were used to estimate TRS from the 2003/04 cropping season. All the forecast models for ratoon crops were significant indicating that they are an excellent tool to optimize agricultural planning
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