1,044 research outputs found

    Teaching Maltese as a second language to adults

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    Coherent Population Trapping with Controlled Interparticle Interactions

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    We investigate Coherent Population Trapping in a strongly interacting ultracold Rydberg gas. Despite the strong van der Waals interactions and interparticle correlations, we observe the persistence of a resonance with subnatural linewidth at the single-particle resonance frequency as we tune the interaction strength. This narrow resonance cannot be understood within a meanfield description of the strong Rydberg--Rydberg interactions. Instead, a many-body density matrix approach, accounting for the dynamics of interparticle correlations, is shown to reproduce the observed spectral features

    High-coherence electron and ion bunches from laser-cooled atoms

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    XXVIII ICPEACCold atom electron and ion sources produce electron bunches and ion beams by photoionisation of laser cooled atoms. They offer high coherence and the potential for high brightness, with applications including ultrafast electron diffractive imaging of dynamic processes at the nanoscale. Here we present our cold atom electron/ion source, with an electron temperature of less than 10 K and a transverse coherence length of 10 nm. We also discuss experiments investigating space-charge effects with ions and the production of ultra-fast electron bunches using a femto-second laser. In the latter experiment we show that it is possible to produce both cold and fast electron bunches with our source.A. J. McCulloch, D. V. Sheludko, C. T. Putkunz, S. D. Saliba, D. J. Thompson, R. W. Speirs, D. Murphy, J. Torrance, B. M. Sparkes, and R. E. Scholte

    PO-518 Biomarker signature defines a potential therapeutic subclass of triple negative breast cancer

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    Introduction: Triple Negative Breast Cancer (TNBC) is associated with a worse prognosis among breast cancer subtypes due to the lack of targeted therapy. The protein phosphatase 2A (PP2A) is a heterogeneous tumour suppressor complex that is tightly regulated in terms of activity and target specificity. Oncogenic inactivation of PP2A is known to be mediated by various mechanisms. The overexpression of inhibitory regulators and increased phosphorylation of PP2A targets have been associated with the TNBC subtype and a worse prognosis. PP2A is predicted to be deregulated in 60% of TNBC and presents a potential target for therapy. Here, we use novel biomarkers, AURKA and KIF2C to identify a TNBC subclass with actionable PP2A deregulation.peer-reviewe

    Matéria seca, proteína bruta, nitrogênio amoniacal e pH das silagens de três genótipos de milheto (Pennisetum glaucum (L). R. Br.) em diferentes períodos de fermentação.

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    Os teores de matéria seca (MS), proteína bruta (PB), nitrogênio amoniacal (N-NH3) e pH foram determinados no material original e nas silagens de três genótipos de milheto, após 1, 3, 5, 7, 14, 28 e 56 dias de fermentação, em silos de laboratório. Os teores de MS das silagens variaram de 23,12 a 24,49%. Os valores médios da PB foram de 10,95% nos materiais originais e 10,40% nas silagens, no 56º dia. No último período de avaliação os valores médios de N-NH3 e pH das silagens foram, respectivamente de 8,75% e 3,62. Os teores de matéria seca e proteína bruta não sofreram mudanças significativas ao longo do processo fermentativo (P>0,05). Houve um aumento nos valores de nitrogênio amoniacal ao longo dos dias de abertura, sem tendência de estabilização. Já os valores de pH estabilizaram-se após 14 dias de fermentação

    Room-Temperature Cubic Phase Crystallization and High Stability of Vacuum-Deposited Methylammonium Lead Triiodide Thin Films for High-Efficiency Solar Cells

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    Methylammonium lead triiodide (MAPI) has emerged as a high-performance photovoltaic material. Common understanding is that at room temperature it adopts a tetragonal phase and it only converts to the perfect cubic phase around 50-60 ºC. Most MAPI films are prepared using a solution-based coating process, yet they can also be obtained by vapor phase deposition methods. Vapor phase processed MAPI films have significantly different characteristics compared to their solvent processed analogous, such as a relatively small crystal grain sizes and short excited state lifetimes. Yet solar cells based on vapor phase processed MAPI films exhibit high power conversion efficiencies. Surprisingly, after detailed characterization we find that our vapor phase processed MAPI films adopt a cubic crystal structure at room temperature that is stable for weeks, even in ambient atmosphere. Furthermore, we demonstrate that by tuning the deposition rates of both precursors during co-deposition it is possible to vary the perovskite phase from cubic to tetragonal at room temperature. Our finding challenges the common belief that MAPI is only stable in tetragonal phase at room temperature. Additionally, these findings can be used to explain the somewhat unexpected high performance of solar cells based on vacuum processed MAPI films with sub 100 nm grain sizes and excited state lifetimes < 100 nanoseconds

    Desempenho produtivo e características de carcaça de ovinos terminados em pastagem nativa da Caatinga submetidos a diferentes suplementações de sal mineral.

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    Resumo: Objetivou-se com este estudo avaliar a influência de diferentes suplementos minerais sobre o desempenho e características de carcaça de ovinos em pastagem nativa da Caatinga. Utilizaram-se 24 ovinos em terminação mestiços Santa Inês, distribuídos em um delineamento inteiramente casualisado, em três tratamentos, conforme as seguintes suplementações de sal mineral: sal mineral comercial (SALMINC), sal mineral comercial acrescido de 750 ppm de zinco animal-1 (SALMINCZn) e sal comercial com fornecimento de 2,5 ml por peso vivo metabólico (PV)0,75 animal-1 de propilenoglicol (SALMINCPeg), com oito repetições cada. Não foi verificado diferenças (P>0,05) para desempenho, características de carcaça e seus rendimentos. A suplementação mineral acrescida de zinco ou propilenoglicol não implica em melhoria no desempenho e nas características de carcaça de ovinos em pastagem nativa da Caatinga. [Growth performance and carcass characteristics of sheep finished on native pasture Caatinga submitted to different salt mineral supplements]. Abstract: The aim with this study was to evaluate the influence of different mineral supplements on performance and carcass characteristics of sheep on native pasture Caatinga. Were used 24 crossbred sheep Santa Ines in termination, distributed in a completely randomized design, with three treatments, according to the following supplements of mineral salt: commercial mineral salt (SALMINC), commercial mineral salt plus 750 ppm of zinc per animal-1 (SALMINCZn) and commercial mineral salt supply with 2.5 ml of propylene glycol per metabolic body weight (BW)0.75 animal-1 (SALMINCPeg), with eight replicates each. There was no difference (P>0.05) on performance, carcass characteristics and their yields. Mineral supplementation plus of zinc or propylene glycol don't imply in improved in performance and carcass characteristics of sheep in native grass of Caatinga

    Composição bromatológica e perfil de fermentação das silagens de cinco híbridos de capim-sudão (Sorghum bicolor x Sorghum sudanense).

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    Cinco híbridos de Sorghum bicolor x Sorghum sudanense foram analisados sob a forma de forragem verde (P0) e silagem, com sete (P1), 14 (P2), 28 (P3) e 56 (P4) dias de ensilagem. Os híbridos foram cultivados na Embrapa Milho e Sorgo e ensilados aos 60 dias após a semeadura, em silos de tubo de PVC, com quatro repetições por período. Foram determinados os teores de matéria seca (MS), os valores de pH e teores de carboidratos solúveis em álcool (CHO?s), proteína bruta (PB) e nitrogênio amoniacal (N-NH3/NT) e os coeficientes de digestibilidade ?in vitro?da matéria seca (DIVMS) e os componentes da parede celular. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 5 X 5 (híbridos x períodos), com quatro repetições. Foram observadas baixas concentrações de MS, PB e baixos coeficientes de DIVMS para todos os materiais avaliados. Entretanto, os padrões de fermentação das silagens avaliadas foram satisfatórios. Todos os híbridos apresentaram valores semelhantes para a fração fibrosa. Ocorreu aumento dos teores de fenóis totais com a ensilagem e estes mostraram correlação negativa com a DIVMS. Concluiu-se que os teores de MS das silagens foram insatisfatórios, mas, apesar da alta umidade, as silagens apresentaram bons padrões fermentativos. Quanto à qualidade do volumoso, as silagens foram consideradas de média qualidade, em virtude do baixo teor de PB
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