663 research outputs found

    Membrane processing of grape must for control of the alcohol content in fermented beverages

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    The great demand of beverages, both alcohol-free and with low alcohol content, is a great challenge for the production of beverages with controlled alcohol content through the use of sustainable enological practices. The present work addresses this challenge with the processing of grape must by reverse osmosis (RO) for must reconstitution with different sugar contents prior to the alcoholic fermentation. The original must came from grapes grown in Quinta do Quinto, in Santarém, collected after destemming and mechanic crushing, and preserved in a refrigerated chamber at -1.6 °C until processing by RO. The RO processing was carried out in Escola Superior Agrária de Santarém, with a pilot plant equipped with RO spiral wound modules, M38RO, from Alfa Laval, Denmark. The total membrane permeation area is 15 m2. The work pressure was 55 bar. The original must had 23.7 oBrix, a density of 1108 g.L-1, 15.2% (v/v) of probable alcohol, and a conductivity of 2.01 mS.cm-1. The must reconstitution was carried out, by mixing the concentrated grape must with the vegetal water produced by RO (permeate) to obtain beverages with a nominal alcohol content of 5%, 7%, 10% and 13% (v/v). The fermentation average temperature was between 18.2 and 19.7 °C, and the final density rounded about 993 g.cm-3. The beverages were analysed by different parameters, including total polyphenols, total anthocyanins, colour intensity and hue, the coordinates CIELab, alcohol content, total acidity, volatile acidity, pH, free SO2 and total SO2. The attributes of the beverage, corresponding to the visual appearance, aroma and taste senses, as well as the overall judgment were evaluated by the tasters. The proposed method can produce beverages with controlled low alcohol content. The decrease of the alcohol content led to lower content of polyphenols compounds which influenced the sensory evaluation.info:eu-repo/semantics/publishedVersio

    Do Littoral Macrophytes Influence Crustacean Zooplankton Distribution?

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    In a meso-eutrophic reservoir, cladoceran and copepod assemblages were characterised in two sampling sites: One located in the pelagic zone (site 1) and the other in the shallow littoral zone (site 2), the latter colonised by emergent macrophytes. Samples were collected biweekly from June to July 2001 and from May to July 2002 at the two sites. At site 1, crustacean zooplankton samples were obtained by vertical hauls using a Wisconsin type net of 64 mm mesh size. At site 2 several random samples were obtained using a van Dorn bottle. Those samples were pooled together and the total sample was sieved through a 64 mm mesh size. Macrophyte relative abundance for each species was visually estimated. Macrophyte community was composed of Glyceria declinata, Eleocharis palustris and Carex sp. A Mann-Whitney U-test was carried out to test for statistically significant differences between sites, for environmental parameters and crustacean zooplankton species densities. Alona rectangula, Alona costata, Alona quadrangularis and Chydorus sphaericus were only found in littoral samples. Daphnia longispina, Daphnia pulex, Ceriodaphnia pulchella, Bosmina longirostris, Diaphanosoma brachyurum, Copidodiaptomus numidicus, and Acanthocyclops robustus were found at both sites. However, Daphnia and Bosmina densities did not differ significantly between the pelagic and littoral sites. Ceriodaphnia, Diaphanosoma, and C. numidicus densities were significantly higher in the pelagic site, whereas A. robustus densities showed the opposite pattern.En un embalse meso-eutrofico las comunidades de cladóceros y copépodos fueron caracterizadas en dos estaciones de muestreo. Una localizada en la zona pelágica (estación 1) y la otra en la zona litoral (estación 2). Esta última está colonizada por macrofitos emergidos. Los muestreos fueron efectuados quincenalmente de Junio a Julio de 2001 y de Mayo a Julio de 2002 en las dos estaciones. En la estación 1 los muestreos de crustáceos del zooplancton se obtuvieron mediante arrastre vertical utilizando una red tipo Wisconsin de 64 mm de poro. En la estación 2 se realizaron varias muestras aleatorias con una botella tipo van Dorn. Las muestras obtenidas en la estación 2 se juntaron y la muestra total resultante fue filtrada por una red de 64 mm de poro. La abundancia relativa de cada una de las especies de macrófitos fue estimada visualmente. La comunidad de macrófitos está constituida por Glyceria declinata, Eleocharis palustris y Carex sp. Fue realizado el test de U de Mann-Whitney para detectar las diferencias estadísticamente significativas entre las dos estaciones, para los parámetros ambientales y para las densidades de los crustáceos del zooplancton. Alona rectangula, Alona costata, Alona quadrangularis y Chydorus sphaericus se han observado únicamente en los muestreos obtenidos en el litoral. Daphnia longispina, Daphnia pulex, Ceriodaphnia pulchella, Bosmina longirostris, Diaphanosoma brachyurum, Copidodiaptomus numidicus y Acanthocyclops robustus se han encontrado en ambas estaciones, no obstante las densidades de Daphnia y Bosmina no presentan diferencias estadísticamente significativas entre la zona pelágica y la litoral. Las densidades de Ceriodaphnia, Diaphanosoma y C. numidicus fueran significativamente más elevadas en la zona pelágica, mientras que la densidad de A. robustus presentó un patrón opuesto

    Trace elements and Pb isotope variations in galena from the onça gold deposit, Mato Grosso, Brazil: fluid mixing from hydrothermal and crustal sources

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    This study deals with the petrography of sulfídes and quartz veins, Pb isotopes, major and trace elements in galena, microthermometry and Raman spectrometry of fluid inclusions, with the objective of delineating temporal and spatial aspects of the fluid circulation patterns during the origin of the Onça gold deposit, Mato Grosso State, Brazil. The Pb isotope and mineral chemistry data indicate variable sources for the Pb isotopes, major (S and Pb) and trace elements (Sb, Ag, Zn and Se), with increases or decreases of the contents during the growth of the galena crystals. The results suggest that the variation may be due to the contamination of the hydrothermal solution by mixing with components derived from supracrustal host rocks of Pontes e Lacerda metavolcanic-sedimentary sequence. The mineral chemistry and fluids inclusion studies suggest two possible sources for the hydrothermal solutions: (1) deep solutions that originated during the regional metamorphism represented by the Aguapeí metamorphic event where the solutions present aqueous-carbonic composition and Iow salinity. Geologic control of the mineralization is in agreement with this hypothesis because the ore bodies are syntectonic with foliation formed during the Aguapeí event; (2) high contents of base metais indicates a plutonic influence in the origin of the fluids. Geologic controls also are in agreement with this hypothesis because pegmatitic intrusion was synchronous with the mineralizations. The Pb isotope and fluid inclusion relations allows the conclusions that the compositions of the hydrothermal solutes were variable during the emplacement of the quartz veins and the growth of galena crystals. The earlier solutes had hydrocarbons and were more radiogenic, whereas the later solutes had base metais and were less radiogenic. The Onça deposit originated during a metamorphic event by the effect of hydrothermal solutions related to plutonism, and with an important contribution from the host rocks as recorded by the influence of isotope, major and trace element compositions on the growth of ore-forming minerais.Este estudo compreende petrografia de sulfetos e veios de quartzo, elementos traços, maiores e isótopos de Pb em galena, microtermometria e espectrometria Raman em inclusões fluidas com o objetivo de delinear aspectos temporais e espaciais da circulação de fluídos durante a origem do depósito aurífero do Onça, Estado do Mato Grosso. Os resultados de isótopos de Pb e a química mineral indicam uma fonte variável para os isótopos de Pb e para elementos maiores (S e Pb) e elementos traços (Sb, Ag, Zn e Se) com aumentos e diminuições nos seus conteúdos durante o crescimento dos cristais de galena de forma que esta variação pode ser resultado da contaminação da solução hidrotermal pelas rochas supracrustais encaixantes da Seqüência Metavulcano-sedimentar Pontes e Lacerda. A química mineral e o estudo das inclusões fluídas sugerem dois tipos de fontes para as soluções hidrotermais: (1) soluções originadas em profundidade durante o metamorfismo regional representado pelo evento Aguapeí, com soluções aquocarbônicas e de baixa salinidade, hipótese corroborada pela concordância dos corpos de minério com a foliação regional gerada por este evento; (2) altos valores de metais básicos indicam uma influência plutônica na origem dos fluídos. Os isótopos de Pb e os estudos de inclusões fluídas analisadas conjuntamente permitem concluir que a composição das soluções hidrotermais foram variáveis durante o emplacement dos veios de quartzo e o crescimento dos cristais de galena. As soluções iniciais apresentam CR, na sua composição e são mais radiogênicas. As soluções finais apresentam metais básicos em sua composição e são menos radiogênicos. Como conclusão é possível sugerir que o depósito do Onça foi originado durante um evento metamórfico por soluções hidrotermais com influência de plutonismo, com uma importante contribuição das rochas encaixantes na composição isotópica do Pb, nos elementos maiores e traços durante o crescimento dos minerais de minério

    The basic perspectives of consultant-client relationships in management consulting

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    A historical overview, although the existing literature default the management consulting as a extraordinary and a unique phenomenon in the corporate context, in truth these statements do not come accompanied by a number of academic studies that emphasize the importance of effective work of management consultants. To combat the lack of studies in this emerging area, this article aims to understand whether it may be in fact the importance of knowledge produced in this sector is associated with the type of relationships that are built between the parties and, noting that the successful relationships are the basis of the knowledgeproduced in the sector who will then be responsible for the balance of powers and who should take control of projects. The results of the empirical analysis in the form of semi-structured interviews and questionnaires applied to management consultants and managers of SME in Portugal show that you cannot translate the control relationship between consultants and clients across the board, not least because the projects are not all equal, and there are various characteristics thatdistinguish them and that validate assumptions of control that can differ considerably between each oneinfo:eu-repo/semantics/publishedVersio

    NMR conformational study of diamagnetic complexes of some triazatriacetate macrocycles

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    The conformational properties of the diamagnetic complexes formed by five triazatriacetic macrocyclic ligands with monovalent (alkaline) and divalent (alkaline-earth, Zn2+ and Cd2+) cations have been studied by proton nuclear magnetic resonance spectroscopy (1H NMR) in aqueous solution as a function of pH and temperature. These structurally related triazatriacetic ligands, 1,4,7-triazacyclononane-N,N',N''-triacetic acid (NOTA), 1,4,7-triazacyclodecane-N,N',N''-triacetic acid (DETA), 1,4,8-triazacycloundecane-N,N',N''-triacetic acid (UNTA), 1,5,9-triazacyclododecane-N,N',N''-triacetic acid (DOTRA), and 9,10-benzylidene-1,4,7-triazacyclotridecane-N,N',N''-triacetic acid, (BUNTA) have triazamacrocyclic rings with different sizes and flexibilities, bearing three pendant acetate arms. In the case of the alkaline-earth, Zn2+ and Cd2+ cations, only one complex form (1:1) has been detected for all the ligands studied. In most cases the metal ion is coordinated to all the ligand ring nitrogens and to all or some of the carboxylate groups of the pendant arms, except when a poor fit of the cations into the macrocyclic hole occurs, such as for the Ba2+ complexes of DETA, UNTA and DOTRA and the Ca2+ and Sr2+ complexes of BUNTA. The resonance patterns of the ring proton resonances, determined by the long lifetime of the metal-nitrogen bonds, indicate that the six-membered rings formed upon chelation are conformationally rigid and the five-membered rings are conformationally flexible. The multiplicity of the acetate proton resonances shows that the metal-oxygen bonds are long-lived or short lived depending whether the acetates are bound to nitrogens involved in two ring bridges of equal or unequal sizes.http://www.sciencedirect.com/science/article/B6TG5-3T829PD-1D/1/7651a74d4d83a8b051a5d0b9286244e

    Rash, fever and proteinuria after amoxicillin in a SLE patient

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    We report a case of severe type IV hypersensitivity reaction to amoxicillin, which occurred in a person with a 12-year history of SLE. The present case illustrates the wide differential diagnosis in a SLE patient who presents with an allergic drug reaction. The attribution of the presenting symptoms to the underlying SLE and/or to the drugs used to treat SLE and coexisting conditions is a major challenge

    a mixed methods study

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    (U-th)/he ages from the fuorite mineralization of the Tanguá Alkaline intrusion

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    The Tanguá Alkaline Suite formed as a result of Mesozoic to Cenozoic magmatic events that affected the part of the South American Platform in Brazil’s southeast. The alkaline intrusion is composed of alkali-feldspar syenite with nepheline (pulaskites and umptekites), syenite (with or without the presence of pseudo-leucite), varied nepheline syenites (foyaites, micro-foyaites etc.) and alkaline magmatic breccias. The intrusion contains important fluorite mineralization, in the form of NE-SW oriented veins, which were economically extracted in recent decades at the Emitang Mine. This paper focuses on the analysis of these centimetric crystals of fluorite which vary in color from (yellow, to white and pur-ple.) associated with mineralization of Tanguá Body. Geochronological dating by (U-Th)/He of fluorite mineralization showed a wide range of ages, with the oldest age of 74 ± 3 Ma (Late Cretaceous) and the youngest of 0.11 ± 0.02 Ma (Late Pleistocene). Most ages are concentrated between 25 and 8 Ma (Miocene). The oldest age (74.0 ± 3 Ma) is associated with hydrothermal fluids percolating at the time of intrusion of the Tanguá Body. The other ages represent episodes of percolation of hydrothermal fluids and consequent growth of fluorite crystals. Of note is a set of Miocene ages that can be associated with regional tectonic events. This phase of flurite growth may be associated with the reactivation of basement faults and structures in the Tanguá region and the circulation of hydrothermal fluids associated with intrusion of younger dikes. The youngest ages may be associated with neotectonic reactivation of faults during neotectonic events
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