2,559 research outputs found

    Cambios en elrango de distribución dePotentilla tucumanensis (Rosaceae), una especie críptica en peligro de extinción

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    Una correcta identificación taxonómica es esencial para la preservación de la biodiversidad. En este trabajo se presentan caracteres morfológicos sencillos para diferenciar la nueva especip, Potentilla tucumanensis recientemente descripta. Esta especie, cuyo período reproductivo ocupa el 10% final de su ciclo de vida, es considerada críptica debido a que puede ser confundida por su similitud en estado vegetativo, con especies con las cuales cohabita y está aislada reproductivamente. Además, se muestra que en los últimos cien años, P. tucumanensis ha sufrido una dramática retracción de su hábitat: desde 1900 a 1925 se encontraron ejemplares de esta planta distribuidos en diferentes ambientes ecológicos de la reglón del noroeste argentino, mientras que en la actualidad, esta especie es raramente encontrada y siempre confinada a un sólo tipo de hábitat. Se discuten las posibles causas de este proceso de retracción. Si P. tucumanensis no hubiese sido reconocida como una especie nueva, probablemente hubiese desaparecido sin dejar rastro de su existencia.: A correct taxonomic identification is essential for the preservation of biodiversity. In this paper we present simple morphological characters for the identification of the new species recently described, Potentilla tucumanensis. The reproductive period of this species occupies about 10% of the last part of its lifecycle, is considered cryptic because in the vegetative stage it has many morphological similarities with other cohabiting related species; it can be easily confused with them and it is reproductively isolated. Our study also revealed that for the last hundred years P. tucumanensis has suffered a dramatic habitat retraction. Possible causes of this area retraction are discussed. IfPtucumanensis had not been recognized asa new species, it would have most likely disappeared without being noticed.Fil: Arias, Marta Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Diaz Ricci, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Castagnaro, Atilio Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentin

    The Certification of the Contents (Mass Fractions) of Flumequine and Oxolinic Acid in Freeze-dried Salmon Tissue. BCR 725

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    Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

    Commissioning and First Observations with Wide FastCam at the Telescopio Carlos S\'anchez

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    The FastCam instrument platform, jointly developed by the IAC and the UPCT, allows, in real-time, acquisition, selection and storage of images with a resolution that reaches the diffraction limit of medium-sized telescopes. FastCam incorporates a specially designed software package to analyse series of tens of thousands of images in parallel with the data acquisition at the telescope. Wide FastCam is a new instrument that, using the same software for data acquisition, does not look for lucky imaging but fast observations in a much larger field of view. Here we describe the commissioning process and first observations with Wide FastCam at the Telescopio Carlos S\'anchez (TCS) in the Observatorio del Teide.Comment: 7 pages, 8 figures, Proc. SPIE. 9908, Ground-based and Airborne Instrumentation for Astronomy VI, 99082O. (August 09, 2016

    El pasado ¿pisado? : la literatura y el cuidado de la salud

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    Fil: Orofino, María Marta. Grupo Hospitalar Conceição (Porto Alegre, Brasil). Grupo de Pesquisa Narrativas em Saude.Fil: Ricci, Ricardo Teodoro. Universidad Nacional de Tucumán. Facultad de Medicin

    Foetal exposure to maternal stressful events increases the risk of having asthma and atopic diseases in childhood

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    Background:The natural history of asthma and atopic diseases beginsin utero.Studies investigating the influence of foetal exposure to maternal stressful life eventsduring pregnancy (SLEP) on asthma and atopic diseases are lacking.Aim:To test whether the children of mothers who had experienced SLEP are at anincreased risk for asthma, atopic eczema and allergic rhinitis.Methods:The association between maternal SLEP (at least one among: divorce,mourning or loss of the job) and the occurrence of asthma and atopic diseases inchildhood was studied in a population (n = 3854) of children, aged 3–14 yrs, livingin Northern Italy. The parents filled in a standardized questionnaire about the chil-dren’s health and the events occurred to their mothers during pregnancy.Results:Three hundred and thirty-three (9%) of the mothers experienced SLEP.Their children had a statistically significantly higher lifetime prevalence of wheezing(31.6% vs. 23.1%), asthma (8.9% vs. 5.6%), allergic rhinitis (10.9% vs. 7.3%) andatopic eczema (29.7% vs. 21.1%) than those of mothers without SLEP. Afteradjusting for potential confounders, the foetal exposure to SLEP was positivelyassociated with wheezing (OR: 1.41, 95% CI: 1.03–1.94), asthma (OR: 1.71, 95%CI: 1.02–2.89), allergic rhinitis (OR: 1.75, 95% CI: 1.08–2.84) and atopic eczema(OR: 1.53, 95% CI: 1.11–2.10).Conclusion:The children of mothers who had experienced SLEP were at a moder-ately increased risk of having wheezing, asthma, eczema and allergic rhinitis duringtheir childhood. Maternal stress during pregnancy might enhance the expression ofasthma and atopic phenotypes in children.Pediatric Allergy and Immunology724Pediatric Allergy and Immunology23(2012) 724–729ª2012 John Wiley & Sons A/S. Published by Blackwell Publishing Lt

    Taxa de crescimento e estado nutricional do cafeeiro em sistema de produção orgânico

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    Devido a baixa concentração de N nos fertilizantes orgânicos, são necessárias doses elevadas dessas fontes para suprir as exigências do cafeeiro. Por esta razão, o N é o nutriente mais limitante na cafeicultura orgânica. O objetivo do trabalho foi avaliar, em sistema orgânico de produção, a influência da Crotalaria juncea no crescimento e estado nutricional de cultivares de café, bem como quantificar o aporte de biomassa vegetal e de N via fixação biológica, além do efeito sobre as características químicas do solo. O experimento foi constituído por seis cultivares de café (Coffea arabica), cultivadas com e sem Crotalaria juncea. A crotalária foi semeada em novembro de 2001, e aos 76 dias foi podada a meia altura. Aos 175 dias, foi cortada e quantificada a biomassa vegetal, os teores de N, P, K, Ca, Mg e a abundância natural de 15N. O cultivo da crotalária proporcionou o aporte de 16 t ha-1 de matéria seca e a reciclagem de 444, 21, 241, 191 e 44 kg ha-1 de N, P, K, Ca e Mg, respectivamente. Os cultivares 'Obatã' e 'Catuaí Vermelho' apresentaram as maiores taxas de crescimento em altura, enquanto os cultivares 'Icatu' e 'Oeiras', as menores taxas. A fixação biológica de N proporcionou um aporte de N superior a 200 kg ha-1 de N, demonstrando ser uma alternativa para o produtor fertilizar os sistemas orgânicos com N. O cultivo da crotalária permitiu que o teor de N acumulado no tecido foliar dos cafeeiros se mantivesse igual após um ciclo da cultura, ao contrário do que foi observado nas parcelas não cultivadas com a leguminosa.In view of the low N concentration in organic fertilizers, it is necessary to use high rates of such fertilizers to attend coffee crop requirements. Hence, N is the most limiting nutrient for organic coffee production. The objective of this work was to evaluate the influence of sunn hemp (Crotalaria juncea) organic fertilization on the growth and nutritional status of coffee cultivars, as well as to quantify plant biomass and N input derived from biological nitrogen fixation, and their effect on soil chemical characteristics. The experiment consisted of six coffee (Coffea arabica) cultivars intercropped with and without sunn hemp sown in November 2001 and pruned at mid-height 76 days later. At 175 days, the standing biomass of the legume was cut, measuring dry mass, total N, P, K, Ca, Mg, and 15N natural abundance, resulting 16 t ha-1 of dry mass and the recycling of 444, 21, 241, 191, and 44 kg ha-1 of N, P, K, Ca, and Mg, respectively. Cultivars 'Obatã' and 'Catuaí Vermelho' presented the highest growth rates in terms of plant height, while cultivars 'Icatu' and 'Oeiras' presented the lowest rates. Biological nitrogen fixation associated to the legume introduced more than 200 kg ha-1 of N, which is a demonstration that N fertilization in organic cropping systems is a valuable alternative. Intercropping lead to a constant coffee leaf N content during the entire cropping cycle, contrary to what was observed in plots grown without sunn hemp
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