29 research outputs found

    Abscisic acid as a potential chemical thinner for peach

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    Abstract:The objective of this work was to evaluate the effect of abscisic acid, applied at different rates and different fruit developmental stages, on the thinning of 'Chiripá' peach. Abscisic acid (ABA) at 500 mg L-1 was applied at three stages of fruit development based on lignin deposition: stage 1, at 24 days after full bloom (DAFB); stage 2, at 40 DAFB; and stage 3, at 52 DAFB. Only ABA application at stage 2 - 40 DAFB - reduced fruit set and the number of fruit per plant. Three ABA concentrations (350, 500, and 750 mg L-1) were then applied at 40 DAFB. All rates increased fruit ethylene production and fruit abscission

    A História da Alimentação: balizas historiográficas

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    Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

    ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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    Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

    Gas exchanges and photochemical efficiency of hydroponic bell pepper under salinity and plant density

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    ABSTRACT Gas exchanges and chlorophyll a fluorescence are ways to physiologically analyze the response of plants to salt stress. In this context, the present work was conducted between August and November 2016 in a greenhouse at the Federal University of Campina Grande (7°12’52” S, 35°54’24” W, mean altitude of 550 m), using bell pepper plants cv. All Big, exposed to levels of nutrient solution electrical conductivity (1.7, 3.7, 5.7, 7.7, 9.7 and 11.7 dS m-1) and cultivated in hydroponic system, spaced by 0.2 and 0.3 m, focusing on the analysis of gas exchanges and photochemical efficiency. The experimental design was completely randomized, in a 6 x 2 factorial scheme, with five replicates. Plant density influenced the sensitivity of the gas exchanges to salinity and, when reduced, mitigated its effects at higher salinity levels. Increasing plant density at high levels of electrical conductivity caused damage to the photosynthetic apparatus and even reduced the levels of efficiency of the photosystem II from 3.98 dS m-1

    Removal of the Textile Dye Indanthrene Olive Green from Aqueous Solution Using Chitosan

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    The kinetics and equilibrium of the adsorption of Indanthrene Olive Green (IOG) from aqueous solution onto chitosan have been investigated. The chitosan was characterised in terms of its average degree of de-acetylation (DD) and by XRD, TGA/DTG, IR, SEM and specific BET surface area methods. Batch adsorptions experiments were carried out at different pH values and dye concentrations. It was found that the adsorption process was favoured by acidic pH conditions (4.0–6.0). The adsorption followed second-order rate kinetics and the experimental equilibrium data followed the Langmuir isotherm, thereby suggesting that chemisorption might be the major adsorption mode. Such adsorption also occurred on chitosan fibres, although to a significantly lower extent than on crushed chitosan. The corresponding thermodynamic parameters (ΔG 0 , ΔH 0 and ΔS 0 ) were calculated. The positive values obtained for ΔH 0 (161.7 kJ/mol) and ΔS 0 [559.9 J/(mol K)] suggest that the adsorption process was endothermic, with the randomness of the system increasing during the adsorption process. A simplified adsorption model has also been proposed

    New seminal plasma removal method for freezing stallion semen

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    Seminal plasma removal, an indispensable step in equine semen cryopreservation, is usually done by centrifugation, but this might cause mechanical damage to sperm. A new method for seminal plasma removal from stallion semen, namely a filter composed of a synthetic hydrophilic membrane (Sperm Filter, BotuPharma, Botucatu, Sao Paulo, Brazil), was recently proposed. The objective of this study was to test the use of the Sperm Filter in the removal of seminal plasma before freezing stallion semen. Ejaculates from 31 stallions were divided into two groups and cryopreserved. In group 1 (G1), seminal plasma was removed with the Sperm Filter, and in group 2 (G2), seminal plasma was removed by centrifugation (600× g for 10 minutes). There were no differences (P < 0.05) between G1 and G2 in sperm kinetic parameters or plasma membrane integrity before or after cryopreservation. However, sperm recovery rate was higher (P < 0.05) for G1 versus G2 (mean ± SD, 89.4 ± 7.4% vs. 80.9 ± 5.5%). Therefore, the Sperm Filter was as efficient as centrifugation in removing seminal plasma from the stallion ejaculate. However, filtering was more practical and had significantly fewer sperm lost than the centrifugation technique. © 2013 Elsevier Inc

    Removal of the Textile Dye Indanthrene Olive Green from Aqueous Solution Using Chitosan

    No full text
    The kinetics and equilibrium of the adsorption of Indanthrene Olive Green (IOG) from aqueous solution onto chitosan have been investigated. The chitosan was characterised in terms of its average degree of de-acetylation (DD) and by XRD, TGA/DTG, IR, SEM and specific BET surface area methods. Batch adsorptions experiments were carried out at different pH values and dye concentrations. It was found that the adsorption process was favoured by acidic pH conditions (4.0–6.0). The adsorption followed second-order rate kinetics and the experimental equilibrium data followed the Langmuir isotherm, thereby suggesting that chemisorption might be the major adsorption mode. Such adsorption also occurred on chitosan fibres, although to a significantly lower extent than on crushed chitosan. The corresponding thermodynamic parameters (ΔG 0 , ΔH 0 and ΔS 0 ) were calculated. The positive values obtained for ΔH 0 (161.7 kJ/mol) and ΔS 0 [559.9 J/(mol K)] suggest that the adsorption process was endothermic, with the randomness of the system increasing during the adsorption process. A simplified adsorption model has also been proposed
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