1,747 research outputs found

    New infrared star clusters in the Northern and Equatorial Milky Way with 2MASS

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    We carried out a survey of infrared star clusters and stellar groups on the 2MASS J, H and K_s all-sky release Atlas in the Northern and Equatorial Milky Way (350 < l < 360, 0 < l < 230). The search in this zone complements that in the Southern Milky Way (Dutra et al. 2003a). The method concentrates efforts on the directions of known optical and radio nebulae. The present study provides 167 new infrared clusters, stellar groups and candidates. Combining the two studies for the whole Milky Way, 346 infrared clusters, stellar groups and candidates were discovered, whereas 315 objects were previously known. They constitute an important new sample for future detailed studies.Comment: Accepted to Astronomy and Astrophysic

    Quadratic Effective Action for QED in D=2,3 Dimensions

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    We calculate the effective action for Quantum Electrodynamics (QED) in D=2,3 dimensions at the quadratic approximation in the gauge fields. We analyse the analytic structure of the corresponding nonlocal boson propagators nonperturbatively in k/m. In two dimensions for any nonzero fermion mass, we end up with one massless pole for the gauge boson . We also calculate in D=2 the effective potential between two static charges separated by a distance L and find it to be a linearly increasing function of L in agreement with the bosonized theory (massive Sine-Gordon model). In three dimensions we find nonperturbatively in k/m one massive pole in the effective bosonic action leading to screening. Fitting the numerical results we derive a simple expression for the functional dependence of the boson mass upon the dimensionless parameter e^{2}/m .Comment: 10 pages, 2 figure

    Rendimento de carne de pirarucu, Arapaima gigas (Cuvier).

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    bitstream/item/42268/1/Boletim-Pesquisa-150-CPATU.pd

    First Diabetic Retinopathy Prevalence Study in Portugal: RETINODIAB Study-Evaluation of the Screening Programme for Lisbon and Tagus Valley Region

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    BACKGROUND/AIMS: In Portugal, so far, there is no study or even accurate data on the prevalence of diabetic retinopathy (DR), based on a large representative sample and on a long-term follow-up. The objective of our study was to determine the prevalence of DR based on a national screening community-based programme. METHODS: A 5-year retrospective analysis of the RETINODIAB screening programme results was implemented in Lisbon and Tagus Valley area between July 2009 and October 2014. We estimated the prevalence of retinopathy for all patients with type 2 diabetes and studied the association between known risk factors and retinopathy emergence at their first screening. RESULTS: Throughout this period, from a total of 103 102 DR readable screening examinations, 52 739 corresponded to patients who attended RETINODIAB screening at entry. Globally, DR was detected in 8584 patients (16.3%). Of these, 5484 patients (10.4%) had mild non-proliferative (NP) DR, 1457 patients (2.8%) had moderate NPDR and 672 (1.3%) had severe NPDR. Finally, 971 patients (1.8%) had proliferative DR requiring urgent referral to an ophthalmologist. The presence of any DR, non-referable DR or referable DR was strongly associated with increasing duration of diabetes and earlier age at diagnosis. CONCLUSIONS: The prevalence rate of DR in our study (16.3%) was slightly lower than other published international data. The RETINODIAB network proved to be an effective screening programme as it improved DR screening in Lisbon and Tagus Valley surrounding are

    Avaliação de influência da cama de frango na composição de substrato para formação de mudas de açaizeiro.

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    bitstream/item/27768/1/com.tec.89.pd

    Uso de composto orgânico de lixo urbano na produção de mudas de abieiro.

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    bitstream/item/28287/1/ComTec86.pd

    Efeito de doses percentuais de cama de frango na produção de mudas de abieiro.

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    bitstream/item/27949/1/com.tec.90.pd

    Composto orgânico de lixo urbano na formação de mudas de açaizeiro.

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    bitstream/item/18716/1/com.tec.87.pd
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