2,226 research outputs found

    Achilles Tendon mechanical behavior and ankle joint function at the walk-to-run transition

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    Walking at speeds higher than transition speed is associated with a decrease in the plantar-flexor muscle fibres' ability to produce force and, potentially, to an impaired behaviour of the muscle-tendon unit (MTU) elastic components. This study aimed to investigate the ankle joint functional indexes and the Achilles tendon mechanical behaviour (changes in AT force and power) to better elucidate the mechanical determinants of the walk-to-run transition. Kinematics, kinetic and ultrasound data of the gastrocnemius medialis (GM) were investigated during overground walking and running at speeds ranging from 5-9 km·h-1. AT and GM MTU force and power were calculated during the propulsive phase; the ankle joint function indexes (damper, strut, spring and motor) were obtained using a combination of kinetic and kinematic data. AT force was larger in running at speeds > 6.5 km/h. The contribution of AT to the total power provided by the GM MTU was significantly larger in running at speeds > 7.5 km/h. The spring and strut indexes of the ankle were significantly larger in running at speeds > 7.5 km/h. These data suggest that the walk-to-run transition could (at least partially) be explained by the need to preserve AT mechanical behaviour and the ankle spring function

    Characterisation of an urban bridge portfolio and multi-risk prioritisation accounting for deterioration and seismic vulnerability

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    This contribution proposes a procedure to prioritise retrofit interventions on stocks of bridges according to their seismic vulnerability. The procedure also combines a previously presented approach to evaluate deterioration effects on bridges at a territorial scale. Thereby, the combi-nation of the two approaches provides a multi-risk classification method for bridge stocks. This method also allows refined prioritisation within each class, based on the proposed quantitative indices and on multicriteria decision-making methods. The method was applied to the bridge stock managed by the municipality of Padova, in North-East Italy. First, an extensive charac-terisation of the analysed stock is provided, according to typological, geometric, and structural parameters. Then, the application of the combined approach is presented, highlighting which bridge types resulted more vulnerable to either seismic actions or deterioration effects

    Influence of rootstocks and pruning times on yield and on nutrient content and extraction in 'Niagara Rosada' grapevine.

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    The objective of this work was to evaluate the influence of rootstocks and pruning times on yield and on nutrient content and extraction by pruned branches and harvested bunches of 'Niagara Rosada' grapevine in subtropical climate. The rootstocks 'IAC 766', 'IAC 572', 'IAC 313', 'IAC 571‑6', and '106‑8 Mgt' were evaluated. Treatments consisted of a combination between five rootstocks and three pruning times. At pruning, fresh and dry matter mass of branches were evaluated to estimate biomass accumulation. At harvest, yield was estimated by weighing of bunches per plant. Branches and bunches were sampled at pruning and at harvest, respectively, for nutrient content analysis. Nutrient content and dry matter mass of branches and bunches were used to estimate total nutrient extraction. 'Niagara Rosada' grapevine grafted onto the 'IAC 572' rootstock had the highest yield and dry matter mass of bunches, which were significantly different from the ones observed in 'Niagara Rosada'/'IAC 313'. 'Niagara Rosada' grafted onto the 'IAC 572' rootstock extracted the largest quantity of K, P, Mg, S, Cu, and Fe, differing from 'IAC 313' and 'IAC 766' in K and P extraction, and from '106‑8 Mgt' in Mg and S extraction. Winter pruning results in higher yield, dry matter accumulation by branches, and total nutrient content and extraction.Título em português: Influência de porta?enxertos e épocas de poda na produtividade e no teor e na extração de nutrientes na videira 'Niagara Rosada'

    A neurally-interfaced hand prosthesis tuned inter-hemispheric communication

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    Purpose: This work investigates how a direct bidirectional connection between brain and hand prosthesis modifies the bi-hemispheric sensorimotor system devoted to the movement control of the lost limb. Hand prostheses are often unable to satisfy users' expectations, mostly due to the poor performance of their interfacing system. Neural Interfaces implanted inside nerves of the stump offer the advantage of using the bidirectional neural pathways 'naturally' dispatching signals to control proper hand actions and feed-back sensations. Learning to control a neurally-interfaced hand prosthesis and decode sensory information was previously observed to reduce the inter-hemispheric asymmetry of cortical motor maps and the clinical symptoms of phantom limb syndrome. Methods: Electroencephalographic (EEG) data was analysed using Functional Source Separation (FSS), a semi-blind method that incorporates prior knowledge about the signal of interest into data decomposition to give access to cortical patch activities. Results: Bi-hemispheric cortices showed normalization of their activity (topographical and spectral patterns) and of functional connectivity between homologous hand controlling areas, during the delivery of the motor command to the cybernetic prosthesis. Conclusions: The re-establishment of central-peripheral communication with the lost limb induced by a neurally-interfaced hand prosthesis produces beneficial plastic reorganization, not only restructuring contralateral directly-connected control areas, but also their functional balance within the bi-hemispheric system necessary for motor control

    Indução da brotação de videira da cultivar niágara rosada com o uso de ERGER® associado a nitrato de cálcio em Botucatu, SP.

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    A utilização de indutores de brotação em fruteiras de origem de clima temperado é uma prática consolidada em todas regiões do Brasil e do mundo. Em videiras, assim como em outras frutíferas temperadas, o Dormex® é o produto mais utilizado devido sua alta eficiência. Pelo fato de não existir outros promotores de brotação com sua eficácia, seu valor financeiro e elevado nível toxicológico são barreiras que os produtores encaram para manter a produção vitícola. Resultados promissores na literatura indicam que o Erger® associado ao nitrato de cálcio apresentam influencia na brotação de frutíferas de clima temperado

    Estimativa dos coeficientes de cultivo (kc) de videiras para suco.

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    A fração da área coberta pelo dossel (fc) tem sido empregada, em diferentes regiões, para a estimativa do coeficiente de cultivo (Kc) de videiras. O presente trabalho teve por objetivo estimar os valores de Kc de videiras destinadas à produção de uvas para elaboração de suco com base nos valores de fc, nas condições do noroeste paulista. As avaliações foram realizadas de agosto a novembro de 2016 no município de Votuporanga (SP), com as cultivares Isabel Precoce e BRS Carmem enxertadas sobre os porta-enxertos ?IAC 572? e ?IAC 766?. As videiras foram conduzidas no sistema espaldeira e irrigadas por microaspersores. Os valores de fc foram obtidos ao longo do ciclo da cultura e correlacionados à soma térmica diária (ST) por meio de modelos de regressão. Os coeficientes de cultivo (Kc), foram obtidos em função da fc com base no modelo de Allen e Pereira (2009). Para a cultivar BRS Carmem, os valores de fc em função de ST cresceram de forma contínua, segundo um modelo quadrático, enquanto que, para a cultivar Isabel Precoce, os dados se ajustaram melhor ao modelo de Mitscherlich, apresentando um rápido crescimento inicial e se estabilizando após 500 °C dia, aproximadamente. Os valores médios estimados de Kc para as cultivares Isabel Precoce e BRS Carmem foram iguais a 0,81 e 0,74, respectivamente. O modelo empregado nas avaliações permite a realização de estimativas dos valores de Kc para diferentes condições de cultivo

    Desenvolvimento vegetativo e tensão da água no solo em videiras para suco sobre dois porta-enxertos.

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    RESUMO: O presente trabalho teve por objetivo avaliar o efeito de dois porta-enxertos sobre o desenvolvimento vegetativo e as tensões da água no solo em videiras destinadas à elaboração de suco, sob condições irrigadas. As avaliações foram realizadas de agosto a dezembro de 2015 no município de Votuporanga (SP), com a cultivar Isabel Precoce enxertada sobre os portaenxertos ?IAC 572? e ?IAC 766?. As plantas foram sustentadas no sistema espaldeira e irrigadas por microaspersores. Tensiômetros foram instalados a 0,10 m e 0,30 m de profundidade, para monitorar as tensões da água no solo. Foram determinados os índices de área foliar, a altura da copa e a porcentagem da área sombreada das videiras. As tensões da água no solo apresentaram comportamento semelhante nos dois porta-enxertos. Não foram observadas diferenças significativas entre as variáveis de crescimento vegetativo nas videiras. Concluiu-se que os porta-enxertos ?IAC 572? e ?IAC 766? não afetaram o desenvolvimento vegetativo e as tensões da água no solo para a cultivar Isabel Precoce, em condições irrigadas. PALAVRAS-CHAVE: viticultura, irrigação, evapotranspiraçã

    Clinical and experimental efficacy of gemtuzumab ozogamicin in core binding factor acute myeloid leukemia

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    Leukemia-initiating cells of core binding factor (CBF) acute myeloid leukemia (AML) likely derive from early committed hematopoietic precursors expressing CD33. As such, targeting CD33 could ameliorate the chance of cure of CBF AML patients. We compared 12 CBF AML patients treated with Fludarabine, Cytarabine, Idarubicin and Gemtuzumab Ozogamicin (FLAI-GO regimen) with 25 CBF AML patients treated with the same schedule, but without GO. With the limit of small numbers, we observed a consistent trend toward better overall survival, disease free survival and event free survival in the FLAI-GO group. We also demonstrated the ability of GO to induce the disappearance in vitro of the AML1-ETO molecular transcript in a polymerase chain reaction-positive graft without decreasing the clonogenic potential of CD34+/CD38- cells. This represent the proof of principle for using GO in a purging strategy before autologous stem cell transplantation. Therefore, our data argue in favor of the reinstitution of GO in the therapy of CBF AML

    Measurement of the ttˉproductioncrosssectionint\bar{t} production cross section in p\bar{p}collisionsat collisions at \sqrt{s}$ = 1.8 TeV

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    We update the measurement of the top production cross section using the CDF detector at the Fermilab Tevatron. This measurement uses ttˉt\bar{t} decays to the final states e+νe+\nu+jets and μ+ν\mu+\nu+jets. We search for bb quarks from tt decays via secondary-vertex identification or the identification of semileptonic decays of the bb and cascade cc quarks. The background to the ttˉt\bar{t} production is determined primarily through a Monte Carlo simulation. However, we calibrate the simulation and evaluate its uncertainty using several independent data samples. For a top mass of 175 GeV/c2GeV/c^2, we measure σttˉ=5.1±1.5\sigma_{t\bar{t}}=5.1 \pm 1.5 pb and σttˉ=9.2±4.3\sigma_{t\bar{t}}=9.2 \pm 4.3 pb using the secondary vertex and the lepton tagging algorithms, respectively. Finally, we combine these results with those from other ttˉt\bar{t} decay channels and obtain σttˉ=6.51.4+1.7\sigma_{t\bar{t}} = 6.5^{+1.7}_{-1.4} pb.Comment: The manuscript consists of 130 pages, 35 figures and 42 tables in RevTex. The manuscript is submitted to Physical Review D. Fixed typo in author lis
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