3,401 research outputs found

    Cryopreservation of Byrsonima intermedia embryos followed by room temperature thawing

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    Byrsonima intermedia is a shrub from the Brazilian Cerrado with medicinal properties. The storage of biological material at ultra-low temperatures (-196°C) is termed cryopreservation and represents a promising technique for preserving plant diversity. Thawing is a crucial step that follows cryopreservation. The aim of this work was to cryopreserve B. intermedia zygotic embryos and subsequently thaw them at room temperature in a solution rich in sucrose. The embryos were decontaminated and desiccated in a laminar airflow hood for 0-4 hours prior to plunging into liquid nitrogen. The embryo moisture content (% MC) during dehydration was assessed. Cryopreserved embryos were thawed in a solution rich in sucrose at room temperature, inoculated in a germination medium and maintained in a growth chamber. After 30 days, the embryo germination was evaluated. No significant differences were observed between the different embryo dehydration times, where they were dehydrated for at least one hour. Embryos with a MC between 34.3 and 20.3% were germinated after cryopreservation. In the absence of dehydration, all embryos died following cryopreservation. We conclude that B. intermedia zygotic embryos can be successfully cryopreserved and thawed at room temperature after at least one hour of dehydration in a laminar airflow bench

    Comportamento do pinhão manso no semi-árido brasileiro: resultado do 1. ano.

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    O pinhão manso (Jatropha curcas L.) é um arbusto perene de dois a três metros de altura. A produção de sementes é variável e depende da região, método de cultivo e tratos culturais, bem como da regularidade pluviométrica e fertilidade do solo. Com o objetivo de determinar o potencial produtivo do pinhão manso em condições semi-áridas, com e sem irrigação, foi implantada uma unidade de observação no Campo Experimental da Embrapa, em Petrolina-PE. O espaçamento utilizado foi de 2,0 x 2,0m. O número de frutos e o peso dos frutos e das sementes foram mensurados a partir do quinto mês, em função de sua maturação. Na coleta dos dados, foi considerada como bordadura uma fileira de cada lado e 2,0m no início e no final de cada parcela. A área útil constou de três fileiras com 21 plantas cada. Os resultados aos doze meses após o plantio, quando cultivado sob irrigação complementar, foi muito superior àquele obtido apenas com precipitação pluvial. Os valores médios alcançados, respectivamente para as plantas sem e com irrigação, foram: altura total 1,6 e 2,2m, diâmetro do colo 8,1 e 10,0cm, número de bifurcações abaixo de 50cm de altura 3 e 3 unidades, e número de frutos por planta 210 e 50 unidades. A produtividade média de sementes das plantas irrigadas (1.156kg/ha) foi 3,5 vezes maior do que aquela obtida apenas com o regime normal de chuva (330kg/ha)

    Adaptações em colhedora automotriz para a colheita mecanizada de sementes de capim bufel (Cenchrus ciliaris L.).

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    O trabalho teve por objetivo estudar a possibilidade de utilizar uma colhedora automotriz, na colheita de sementes de capim bufel (Cenchrus ciliaris L.), uma gramínea de grande expressão econômica para a região semi-árida do Nordeste brasileiro. Trata-se de uma tecnologia adaptável às colhedoras automotrizes convencionais, com plataformas flexíveis utilizadas na colheita de soja ou trigo, desde que adotados alguns procedimentos como modificações do tubo de descarga de sementes, cobertura do caracol (inferior) situado no interior do graneleiro, peneiras de trilha e retrilha, sistema de circulação de ar, ajuste da altura da lâmina de corte e velocidade adequada de deslocamento do conjunto automotriz. O rendimento operacional depende do estado de maturação e da quantidade de sementes na área de capim a ser colhida. A tecnologia surge como um avanço tecnológico para a colheita mecanizada de sementes de capim bufel em grandes áreas, pois até então a colheita era efetuada manualmente ou com equipamentos semimecanizados (colhedoras manuais) de baixo rendimento operacional

    Translation and Validation of the Patient Activation Measure in Portuguese People with Type 2 Diabetes Mellitus

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    Introduction: Management of diabetes mellitus is largely dependent on patients' active participation in care. The 'Patient Activation Measure 13' assesses patients' knowledge, skills, and confidence in self-care. We aimed to translate, culturally adapt, and validate the 'Patient Activation Measure 13' to Portuguese, in people with type 2 diabetes. Material and Methods: The translation and cultural adaptation occurred in six phases. A convenience sample of people with type 2 diabetes was recruited from the waiting rooms of a diabetes outpatient centre in Lisbon, between March and April 2014. The questionnaire was self-administered; medical records were reviewed to obtain glycated haemoglobin levels. Main statistical analyses were based on the Rasch rating scale model. Results: The response rate for the final questionnaire was 76%. Rasch analysis was conducted on 193 respondents. Respondents had a mean age of 67.1 (SD 10.1) years, 42.7% were women, and the mean patient activation measure score (0 - 100) in the sample was 58.5 (SD 10.1). The sample was low to moderate in terms of activation: 40.4% were low in activation (levels 1 and 2), 49.7% were in level 3, and 9.8% were in level 4, the highest level of activation. All items had good fit and the response categories functioned well. Item reliability was 0.97 and person reliability was between 0.77 (real) and 0.83 (model). Discussion: The 'Patient Activation Measure 13' was translated and culturally adapted to European Portuguese and validated in people with diabetes, showing good psychometric properties. Future research should aim at evaluating test-retest reliability of the Portuguese 'Patient Activation Measure 13', and exploring its ability to measure changes in activation over time. Conclusion: The 'Patient Activation Measure 13' is now available in European Portuguese and has good psychometric properties.Liliana Laranjo was supported by a Junior Clinical Research award from the Harvard Medical School-Portugal program (HMSP-ICJ/0005/2010; Fundacao para a Ciencia e Tecnologia)

    Pinhão manso.

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    Caracterização do pinhão manso.bitstream/item/133323/1/ID-35735.pd

    The Schwarzschild-de Sitter solution in five-dimensional general relativity briefly revisited

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    We briefly revisit the Schwarzschild-de Sitter solution in the context of five-dimensional general relativity. We obtain a class of five-dimensional solutions of Einstein vacuum field equations into which the four-dimensional Schwarzschild-de Sitter space can be locally and isometrically embedded. We show that this class of solutions is well-behaved in the limit of lambda approaching zero. Applying the same procedure to the de Sitter cosmological model in five dimensions we obtain a class of embedding spaces which are similarly well-behaved in this limit. These examples demonstrate that the presence of a non-zero cosmological constant does not in general impose a rigid relation between the (3+1) and (4+1)-dimensional spacetimes, with degenerate limiting behaviour.Comment: 7 page

    Downbeat nystagmus elicited by eyelid closure

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    We describe a patient with downbeat nystagmus (DBN) evoked only by eye closure. Brain and spinal cord magnetic resonance imaging revealed a T2 paramedian lesion in the left lower basis pontis and other white matter lesions consistent with multiple sclerosis. One potential mechanism for DBN in this case involves transverse ephaptic spread of excitation from areas that subserve coordinated lid closure to the decussating ventral tegmental tract.info:eu-repo/semantics/publishedVersio
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