543 research outputs found

    Interplay of Kerr and Raman beam cleaning with a multimode microstructure fiber

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    We experimentally study the competition between Kerr beam self-cleaning and Raman beam cleanup in a multimode air-silica microstructure optical fiber. Kerr beam self-cleaning of the pump is observed for a certain range of input powers only. Raman Stokes beam generation and cleanup lead to both depletion and degradation of beam quality for the pump. The interplay of modal four-wave mixing and Raman scattering in the infrared domain lead to the generation of a multimode supercontinuum ranging from 500 nm up to 1800 nm

    Self-cleaning on a higher order mode in ytterbium-doped multimode fiber with parabolic profile

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    We experimentally demonstrate polarization-dependent Kerr spatial beam self-cleaning into the LP11 mode of an Ytterbium-doped multimode optical fiber with parabolic gain and refractive index profiles

    High Pressure Processing Applications in Plant Foods

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    High pressure processing (HPP) is a cold pasteurization technology by which products, prepacked in their final package, are introduced to a vessel and subjected to a high level of isostatic pressure (300–600 MPa). High-pressure treatment of fruit, vegetable and fresh herb homogenate products offers us nearly fresh products in regard to sensorial and nutritional quality of original raw materials, representing relatively stable and safe source of nutrients, vitamins, minerals and health effective components. Such components can play an important role as a preventive tool against the start of illnesses, namely in the elderly. An overview of several food HPP products, namely of fruit and vegetable origin, marketed successfully around the world is presented. Effects of HPP and HPP plus heat on key spoilage and pathogenic microorganisms, including the resistant spore form and fruit/vegetable endogenous enzymes are reviewed, including the effect on the product quality. Part of the paper is devoted to the industrial equipment available for factories manufacturing HPP treated productsinfo:eu-repo/semantics/publishedVersio

    Spatiotemporal Characterization of Supercontinuum Extending from the Visible to the Mid-Infrared in Multimode Graded-Index Optical Fiber

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    We experimentally demonstrate that pumping a graded-index multimode fiber with sub-ns pulses from a microchip Nd:YAG laser leads to spectrally flat supercontinuum generation with a uniform bell-shaped spatial beam profile extending from the visible to the mid-infrared at 2500\,nm. We study the development of the supercontinuum along the multimode fiber by the cut-back method, which permits us to analyze the competition between the Kerr-induced geometric parametric instability and stimulated Raman scattering. We also performed a spectrally resolved temporal analysis of the supercontinuum emission.Comment: 5 pages 7 figure

    Resposta de cultivares de trigo à infestação do pulgão Rhopalosiphum padi.

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    O objetivo deste trabalho foi avaliar a resposta de oito cultivares comerciais de trigo (BRS 194, BRS 208, BRS Camboatá, BRS Guabiju, BRS Guamirim, BRS Louro, BRS Timbaúva e BRS Umbu) à infestação do pulgão Rhopalosiphum padi (Hemiptera: Aphididae). O experimento foi realizado na Embrapa Trigo, em telado, em blocos ao acaso, com oito tratamentos e seis repetições, dispostos em parcelas subdivididas. As parcelas principais receberam os tratamentos com e sem infestação de pulgões, e as subparcelas foram compostas pelas cultivares. A infestação com os pulgões (20 adultos ápteros por planta) foi realizada aos 12 dias após a emergência das plantas, quando se encontravam no início do afilhamento, e foi mantida durante 15 dias. As cultivares avaliadas responderam diferentemente à infestação do pulgão R. padi. A cultivar BRS Timbaúva é a mais resistente, e as cultivares BRS Umbu e BRS Guabiju são as mais suscetíveis ao pulgão, quanto ao crescimento e a capacidade produtiva de plantas

    Diagnóstico Ambiental Como Subsídio à Restauração Florestal E Manutenção Hidrológica Da Bacia Do Ribeirão Dos Pinheirinhos, Brotas – Sp

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    The occupation of Ribeirão dos Pinheirinhos caused fragmentation of riparian vegetation, affecting the dynamic environment of the city of Brotas, SP. In this sense, environmental diagnostics acts as an indispensable tool for actions intended to minimize these effects in the medium and long term. The objective of this study was to diagnosis permanent preservation areas (APP) in the basin of Ribeirão dos Pinheirinhos, Brotas - SP, in order to determine priority areas for forest restoration. We used a digital cartographic database and IDRISI Andes GIS for spatial analysis and image processing. Map and soil coverage was generated by the application of supervised classification algorithm for maximum likelihood, and the PPA's defined according to the Brazilian Forest Code, to identify their land use. It was subsequently generated a map of distance to the sources, which crossed the land resulting in the map of priority areas for forest restoration. Agricultural crops and bare soil (73.70%) predominate, leaving only 23.14% of remaining forest. It was observed that 32.09% of APP's are improperly employed. Thus, it is evident the need for investment for conservation of forest remnants, with better planning land use and adaptation to government agencies legislation, since 68.45% of the total area was classified as high to too high priority for restoration, a percentage that increases with the expansion of farming. © 2016, Universidade Estadual Paulista - UNESP. All rights reserved.21111

    [Myositis specific and myositis associated autoantibodies in idiopathic inflammatory myopathies: a serologic study of 46 patients]

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    Objective. To characterize serum autoantibody profiles of patients with idiopathic inflammatory myopathies (IIM) by searching for myositis-specific (MSA) and myositis-associated (MAA) antibodies with sensitive and specific laboratory tests. Methods. We tested the sera from 46 Caucasian patients diagnosed as affected with IIM at the Division of Rheumatology of Padova University (21 polimyositis, PM; 22 dermatomyositis, DM; 3 myositis overlap syndrome). All patients had definite IIM according to the criteria of Bohan-Peter. MSA including anti-tRNA synthetase (anti-Jo-1 and others) and anti-Mi-2 were determined by RNA immunoprecipitation and a modified immunoblot test, respectively. MAA (-U1RNP, -U2RNP, RoRNP, PM/Scl, Ku) were detected by counterimmunoelectrophoresis and immunoblot. Results. Serum MSA and/or MAA were found in 30/46 (65%) patients with IIM. Twenty-three patients (50%) were positive for at least one MSA: anti-Jo-1 in 15 (33%), anti-Mi-2 in 6 (13%), and other anti-tRNA synthetase in 3 (6%).One patient was anti-Jo-1/Mi-2 positive. Moreover, 18 patients (39%) were positive for at least one MAA: anti-Ro/SSA in 13 (28%), anti-U1RNP in 4 (9%), anti-PM/Scl in 1 (2%) and anti-Ku in 1 (2%). Coexisting MSA and MAA were observed in 8 patients (17%), anti-Jo-1/SSA positive in most cases. Anti-Jo-1 was predominantly associated with PM (57% in PM vs 14% in DM), whereas anti-Mi-2 was exclusively found in DM patients (27%). Anti-synthetase antibodies were closely associated with interstitial lung disease and polyarthritis; anti-Mi-2 positive DM patients did not have lung involvement. Notably, anti-Ro/SSA antibody was frequently observed and almost equally detected in either PM or DM (about 30%): in more than 50% of cases the antibody was associated with one MSA. Conclusions. By means of analytically reliable methods, MSA was detected in 50% of our IIM patients. Searching for MSA in patients with IIM is recommended because of its diagnostic and prognostic value
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