4,569 research outputs found

    Neural crest migration is driven by a few trailblazer cells with a unique molecular signature narrowly confined to the invasive front

    Get PDF
    Neural crest (NC) cell migration is crucial to the formation of peripheral tissues during vertebrate development. However, how NC cells respond to different microenvironments to maintain persistence of direction and cohesion in multicellular streams remains unclear. To address this, we profiled eight subregions of a typical cranial NC cell migratory stream. Hierarchical clustering showed significant differences in the expression profiles of the lead three subregions compared with newly emerged cells. Multiplexed imaging of mRNA expression using fluorescent hybridization chain reaction (HCR) quantitatively confirmed the expression profiles of lead cells. Computational modeling predicted that a small fraction of lead cells that detect directional information is optimal for successful stream migration. Single-cell profiling then revealed a unique molecular signature that is consistent and stable over time in a subset of lead cells within the most advanced portion of the migratory front, which we term trailblazers. Model simulations that forced a lead cell behavior in the trailing subpopulation predicted cell bunching near the migratory domain entrance. Misexpression of the trailblazer molecular signature by perturbation of two upstream transcription factors agreed with the in silico prediction and showed alterations to NC cell migration distance and stream shape. These data are the first to characterize the molecular diversity within an NC cell migratory stream and offer insights into how molecular patterns are transduced into cell behaviors

    A utilização da arte no ensino de filosofia em sala de aula

    Get PDF
    Orientador :Monografia (especialização) - Universidade Federal do Paraná, Setor de ..., Curso de Especialização em ...Inclui referênciasResumo

    The elastic wave propagation in rectangular waveguide structure determination of dispersion curves and their application in nondestructive techniques

    Get PDF
    The use of mechanic waves for assessing structural integrity is a well-known non-destructive technique (NDT). The ultrasound applied in the guided wave in particular requires significant effort in order to understand the complexities of the propagation so as to develop new methods in damage detection, in this case, knowing the interaction between the wave propagation and the geometry of the waveguides is mandatory. In the present work, the wave propagation in rectangular steel rod is presented. In this study, the section dimensions were fixed as 5 × 15 [mm], a typical element of the flexible riser structural amour commonly used in the offshore oil industry. The studies here presented were restricted to [0, 100 KHz] frequencies. This frequency interval is in the range of commercial waveguide equipment commonly applied in ducts in NDT applications. The computation of the dispersion curves is performed by using three different methodologies: (i) analytical solutions, (ii) a method that combines analytical approaches with finite element methods (SAFE), and (iii) experimental method that extracted information from the rod using laser vibrometers and piezoelectric actuators. Finally, two applications based on the dispersion curves determined in the rectangular waveguide are presented to illustrate the possibilities of the curve dispersion knowledge related to the specific geometry in the development and application linked to NDT. The first application consists on showing the possibilities of the techniques that use a fiber grating Bragg cell (FGB) to measure the wave displacement and the second application involves the simulation of pre-fissured prismatic waveguide aimed at searching to induce three characteristic acoustic events. The model was built combining the finite element method and a version of the discrete element method

    Associação da educação com a ocorrência de delirium em pacientes de um serviço de emergência

    Get PDF
    Background: Delirium is a neuropsychiatric syndrome with multiple etiological factors. Evaluation of delirium in different settings, especially the Emergency Department (ED) pertaining to different regions of the world with patients from different cultural and educational backgrounds is needed. Objective: To determine the prevalence of delirium and its association with education in an ED in Brazil during a 6-month period. Methods: Patients aged >18 years were randomly selected from ED admissions. The instruments Confusion Assessment Method (CAM) scale, Mini-Mental State Examination (MMSE), Wechsler Logical Memory (WLM) and Charlson comorbidity score were applied to evaluate delirium, cognitive status, and comorbidities. Results: The prevalence of delirium was10.7%. Delirium patients had significantly lower education, MMSE and WLM (immediate and delayed) scores, with 97.4% presenting episodic memory impairment. Patients with delirium had more history of neurological disorders. Three logistic regression models evaluating the association of variables with delirium were developed. Age and MMSE were retained in the first model, WLM scores in the second, and education in the third. Conclusion: To the best of our knowledge, this is the first study estimating the prevalence of delirium in a Brazilian ED. Lower education was associated with the occurrence of delirium.Introdução: Delirium é uma síndrome neuropsiquiátrica, com fatores etiológicos múltiplos. A avaliação de delirium em diferentes ambientes, especialmente no Serviço de Emergência (SE) de diferentes regiões do mundo e com diferentes características culturais e educacionais é necessária. Objetivo: Determinar a prevalência de delirium e associação com educação em um SE no Brasil, durante seis meses. Métodos: Foram randomizados aleatoriamente no SE os pacientes com idade acima de 18 anos. Escala Confusion Assessment Method (CAM), Mini Exame do Estado Mental (MEEM), o teste de Memória Lógica de Wechsler (MLW), e o escore de comorbidade de Charlson foram aplicados para avaliar delirium, status cognitivo, e comorbidades. Resultados: A prevalência de delirium foi 10,7%. Os pacientes com delirium apresentaram significativamente menor escolaridade, escores mais baixos no MEEM e MLW (imediato e tardio), sendo que 97,4% apresentava comprometimento de memória episódica. Pacientes com delirium apresentaram mais história de transtorno neurológico prévio. Três modelos de regressão logística para delirium foram realizados. No primeiro, idade e MEEM foram mantidos no modelo final. No segundo, MLW imediato e tardio; e no terceiro, apenas educação. Conclusão: Este é o primeiro estudo brasileiro, de acordo com nosso melhor conhecimento, a estimar a prevalência de delirium em serviço de emergência. Nível educacional mais baixo foi associado com ocorrência de delirium

    Estudo de solos do município de Inhacorá - RS.

    Get PDF
    bitstream/item/41485/1/Inhacora.pdf; bitstream/item/41487/1/mapa-aptidao.pdf; bitstream/item/41489/1/mapa-capacidade.pdf; bitstream/item/41491/1/mapa-relevo.pdf; bitstream/item/41492/1/mapa-solos.pd

    UTILIZAÇÃO DE VERMICOMPOSTO NO CRESCIMENTO DE MUDAS DE Hovenia dulcis Thunberg

    Get PDF
    Apesar de bem-adaptada ao Sul do Brasil, a Hovenia dulcis é pouco conhecida em nossas condições, principalmente na fase de viveiro. O presente estudo teve como objetivo avaliar o crescimento de mudas de Hovenia dulcis Thunberg sob o efeito de diferentes doses de vermicomposto. O delineamento experimental utilizado foi o inteiramente casualizado com 5 tratamentos e 4 repetições. Os tratamentos foram: Testemunha com 0% de vermicompsto, 10% de vermicomposto, 20% de vermicomposto, 30% de vermicomposto, 40% de vermicomposto, do volume total do tubete de 185 cm3. Decorridos 90 dias da semeadura, foram avaliados os parâmetros: diâmetro do colo, altura da parte aérea, massa seca aérea, massa seca radicular e massa seca total. As plantas de Hovenia dulcis responderam, de forma positiva, em todos os parâmetroas avaliados, à aplicação de vermicomposto. A dose mais indicada para produção de mudas de Hovenia dulcis é a de 40% de vermicomposto

    Estudo de solos do município de Encruzilhada do Sul - RS.

    Get PDF
    bitstream/item/30598/1/Circular-45.pdf; bitstream/item/30600/1/aptidao-bmp-final.pdf; bitstream/item/30616/1/capacidade-bmp-final.pdf; bitstream/item/30623/1/relevo-bmp-final.pdf; bitstream/item/30634/1/vegetacao-bmp-final.pd

    Estudo de solos do município de Esperança do Sul - RS

    Get PDF
    bitstream/item/30800/1/Circular-49.pdf; bitstream/item/33471/1/aptidao.pdf; bitstream/item/33473/1/vegetacao.pd

    Intermediate Field Coupling of Single Epitaxial Quantum Dots to Plasmonic Waveguides

    Full text link
    Key requirements for quantum plasmonic nanocircuits are reliable single-photon sources, high coupling efficiency to the plasmonic structures and low propagation losses. Self-assembled epitaxially grown GaAs quantum dots are close to ideal stable, bright and narrowband single-photon emitters. Likewise, wet-chemically grown monocrystalline silver nanowires are among the best plasmonic waveguides. However, large propagation losses of surface plasmons on the high-index GaAs substrate prevent their direct combination. Here, we show by experiment and simulation that the best overall performance of the quantum plasmonic nanocircuit based on these building blocks is achieved in the intermediate field regime with an additional spacer layer between the quantum dot and the plasmonic waveguide. High-resolution cathodoluminescence measurements allow a precise determination of the coupling distance and support a simple analytical model to explain the overall performance. The coupling efficiency is increased up to four times by standing wave interference near the end of the waveguide.Comment: Accepted at ACS Nano Letters; contains main text and supporting informatio
    corecore