959 resultados para residual biomass


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This work evaluated the effect of seed size and morphology on the development and biomass of durum wheat seedlings. Three different seed-grading sizes selected by sieving were used in glasshouse experiments, and a set of three developmental and 23 biomass-related indices were measured on eight genotypes, at two moisture levels. The influence of seed size on seedling development was studied at high and low temperatures (22\12 mC, and 15\5 mC day\night temperatures, respectively), in growth chambers. The area of the seed and the area of the embryo were the seed morphological traits most affected by seed size. Seed size was strongly associated with seedling development and seedling biomass until the complete extension of the first two leaves, at the fourth leaf stage. The rate of first-leaf growth and the area of the first leaf were the developmental and biomass traits, respectively, most sensitive to seed-grading size.

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O objetivo do trabalho foi avaliar a toxicidade residual de alguns agrotóxicos utilizados em citros sobre Neoseiulus californicus (McGregor) em condições de laboratório. O método de bioensaio adotado foi o de contato residual. Folhas de citros da variedade Pêra, acondicionadas em arenas, foram pulverizadas em torre de Potter. A toxicidade residual dos produtos foi avaliada duas horas e 1; 3; 5; 7; 10; 14 e 21 dias após a aplicação. Em cada arena, foram transferidas dez fêmeas adultas de N. californicus, juntamente com uma quantidade suficiente de Tetranychus urticae, como fonte de alimento. As avaliações de mortalidade foram realizadas 72 horas após a transferência dos ácaros para as arenas. Os agrotóxicos acrinathrin, deltamethrin, dinocap, enxofre, fenpropathrin, óxido de fenbutatin e propargite não causaram mortalidades significativas em adultos de N. californicus. Foram registradas mortalidades de 29,8; 24,0 e 34,1% para ácaros N. californicus expostos a resíduos de duas horas de idade de abamectim, azocyclotin e cyhexatin, respectivamente. Dicofol, pyridaben e chlorfenapyr causaram 100% de mortalidade aos ácaros predadores expostos aos resíduos tóxicos dos acaricidas, com duas horas de idade. Abamectin provocou mortalidade significativa por um período inferior a um dia. Resíduos dos acaricidas azocyclotin, cyhexatin, dicofol, pyridaben e chlorfenapyr provocaram mortalidades significativas por períodos de 1; 1; 10; 10 e 21dias, respectivamente. Os resultados obtidos no presente experimento servem de subsídio para a escolha adequada dos agrotóxicos a serem utilizados em pomares de citros nos quais N. californicus esteja presente ou naqueles em que o predador venha a ser liberado. Esses resultados também servem para a escolha do momento mais favorável para a liberação dos ácaros predadores dessa espécie no campo, após a aplicação de agrotóxicos nos pomares. Estudos conduzidos em condições de campo ainda são necessários para se compreender melhor o efeito desses agrotóxicos sobre o ácaro predador.

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In perennial crops, fertilizers are applied to restore the amount of nutrient removed from the plant by harvesting. Nevertheless, the immobilized nutrient inside the whole plant should be considered. Based on it, the nutrient concentrations in the guava leaf and fruit and the nutrient contents removed by fruits and post-harvest pruning were evaluated in an irrigated orchard, in Petrolina, State of Pernambuco, Brazil. The greatest contents removed by fruits were N and K among the macronutrients, while Fe, Zn and Mn presented higher levels among the micronutrients. More than 60% of the total content of N, P, K, Mg, Fe, and B removed by pruning were immobilized in the leaf and non-marketable fruit.

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Background: The reduction in the amount of food available for European avian scavengers as a consequence of restrictive public health policies is a concern for managers and conservationists. Since 2002, the application of several sanitary regulations has limited the availability of feeding resources provided by domestic carcasses, but theoretical studies assessing whether the availability of food resources provided by wild ungulates are enough to cover energetic requirements are lacking. Methodology/Findings: We assessed food provided by a wild ungulate population in two areas of NE Spain inhabited by three vulture species and developed a P System computational model to assess the effects of the carrion resources provided on their population dynamics. We compared the real population trend with to a hypothetical scenario in which only food provided by wild ungulates was available. Simulation testing of the model suggests that wild ungulates constitute an important food resource in the Pyrenees and the vulture population inhabiting this area could grow if only the food provided by wild ungulates would be available. On the contrary, in the Pre-Pyrenees there is insufficient food to cover the energy requirements of avian scavenger guilds, declining sharply if biomass from domestic animals would not be available. Conclusions/Significance: Our results suggest that public health legislation can modify scavenger population trends if a large number of domestic ungulate carcasses disappear from the mountains. In this case, food provided by wild ungulates could be not enough and supplementary feeding could be necessary if other alternative food resources are not available (i.e. the reintroduction of wild ungulates), preferably in European Mediterranean scenarios sharing similar and socio-economic conditions where there are low densities of wild ungulates. Managers should anticipate the conservation actions required by assessing food availability and the possible scenarios in order to make the most suitable decisions.

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Background: In the yeast biomass production process, protein carbonylation has severe adverse effects since it diminishes biomass yield and profitability of industrial production plants. However, this significant detriment of yeast performance can be alleviated by increasing thioredoxins levels. Thioredoxins are important antioxidant defenses implicated in many functions in cells, and their primordial functions include scavenging of reactive oxygen species that produce dramatic and irreversible alterations such as protein carbonylation. Results: In this work we have found several proteins specifically protected by yeast Thioredoxin 2 (Trx2p). Bidimensional electrophoresis and carbonylated protein identification from TRX-deficient and TRX-overexpressing cells revealed that glycolysis and fermentation-related proteins are specific targets of Trx2p protection. Indeed, the TRX2 overexpressing strain presented increased activity of the central carbon metabolism enzymes. Interestingly, Trx2p specifically preserved alcohol dehydrogenase I (Adh1p) from carbonylation, decreased oligomer aggregates and increased its enzymatic activity. Conclusions: The identified proteins suggest that the fermentative capacity detriment observed under industrial conditions in T73 wine commercial strain results from the oxidative carbonylation of specific glycolytic and fermentation enzymes. Indeed, increased thioredoxin levels enhance the performance of key fermentation enzymes such as Adh1p, which consequently increases fermentative capacity.

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Os ácaros fitoseídeos, especialmente Neoseiulus californicus (McGregor), são importantes agentes de controle biológico de ácaros tetraniquídeos-praga nas culturas de pomáceas no "Alto Valle del Río Negro y Neuquén", Argentina. Neste trabalho, avaliou-se a mortalidade de N. californicus quando exposto a resíduos dos inseticidas azimphos-methyl, carbaryl e cyfluthrin, e dos acaricidas cyhexatin e propargite. Os produtos foram aplicados às concentrações recomendadas em plantas de pereira. Um, três, seis e dez dias após a aplicação (DAA), folhas tratadas foram retiradas das plantas para a preparação de unidades experimentais. Cinco adultos de N. californicus, provenientes de criação-estoque, foram transferidos para cada unidade, onde pólen de taboa foi fornecido como alimento. As unidades foram mantidas a 25 ± 2 ºC, 60 ± 10% de umidade relativa e fotoperíodo de 14 h. A mortalidade do ácaro foi avaliada 24 h após o confinamento. As médias de mortalidade foram comparadas pelo teste de Dunnett, a 5% de probabilidade. A progressão do declínio do efeito dos produtos testados foi submetida à análise de regressão. Nas duas primeiras datas de avaliação, todos os produtos apresentaram valores de mortalidade significativamente diferentes da testemunha tratada com água. Seis dias após a aplicação, propargite, cyhexatin e cyfluthrin apresentaram mortalidade de aproximadamente 30%, enquanto a mortalidade nos tratamentos azimphos-methyl e carbaryl apresentou níveis estatisticamente similares aos da testemunha. Dez dias após a aplicação, a mortalidade em todos os tratamentos não diferiu significativamente da testemunha. O efeito de todos os produtos apresentou declínio progressivo ao longo do período de observação, sendo significativa a 1% de probabilidade a regressão linear negativa para os valores obtidos. Os maiores efeitos negativos sobre a sobrevivência de N. californicus corresponderam aos acaricidas testados. Azimphos-methyl foi o produto que menos afetou a sobrevivência do ácaro predador. Os inseticidas testados, usados na região do "Alto Valle del Río Negro y Neuquén" para o controle de Cydia pomonella, praga-chave das culturas de pomáceas, apresentaram baixa toxicidade sobre N. californicus.

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This work aimed to evaluate the influence of naphthaleneacetic acid (NAA) and gibberellic acid (GA3) plant regulators in in vitro etiolation and subsequent regeneration of the PE x SC-60 pineapple hybrid. Nodal segments of in vitro plants with approximately 5-7 cm height were incubated in basic MS culture medium supplemented with 0.0; 0.5 and 1.0 mg L-1 of naphthaleneacetic acid (NAA) in combination with gibberellic acid (GA3) in concentrations of 0.0; 0.5 and 1.0 mg L-1, and maintained at 27 ºC under dark condition. Evaluations were carried out at 90 and 180 days after incubation period. The best results for length of etiolated stems were obtained with 1.0 mg L-1 of NAA. In the experiment followed by the regeneration, stems with 3 cm from the etiolation treatment, were cultivated in proliferation medium and the number of regenerated plants per treatment was evaluated at 60 days of cultivation. The treatment that promoted the best etiolation of plants also promoted the worst regeneration rates, demonstrating the residual effect of the auxin used in the previous step in the regeneration of plants of the pineapple hybrid evaluated.

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The performance of natural extracts obtained from underutilized and residual vegetal and macroalgal biomass processed with food-grade green solvents was compared with that of commercial antioxidants. Selected extracts were obtained from two terrestrial sources: winery byproducts concentrate (WBC) and chestnut burs hydrothermally fractionated extract (CBAE), and from two underutilized seaweeds: Sargassum muticum extracts, either extracted with ethanol (SmEE) or after alginate extraction and hydrothermal fractionation (SmAE) and from Ulva lactuca processed by mild acid extraction and membrane concentration (UlAE). These extracts showed in vitro antioxidant properties comparable to commercial antioxidants and were safe for topical use based on the absence of skin-irritant effects at 0.1% on reconstructed human tissues. The stability of several cosmetic model emulsions was assessed during accelerated oxidation assays. The incorporation of natural extracts produced from renewable underutilized resources at 0.4-0.5% in an oil-in-water emulsions reduced lipid oxidation during storage.

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Mountain regions worldwide are particularly sensitive to on-going climate change. Specifically in the Alps in Switzerland, the temperature has increased twice as fast than in the rest of the Northern hemisphere. Water temperature closely follows the annual air temperature cycle, severely impacting streams and freshwater ecosystems. In the last 20 years, brown trout (Salmo trutta L) catch has declined by approximately 40-50% in many rivers in Switzerland. Increasing water temperature has been suggested as one of the most likely cause of this decline. Temperature has a direct effect on trout population dynamics through developmental and disease control but can also indirectly impact dynamics via food-web interactions such as resource availability. We developed a spatially explicit modelling framework that allows spatial and temporal projections of trout biomass using the Aare river catchment as a model system, in order to assess the spatial and seasonal patterns of trout biomass variation. Given that biomass has a seasonal variation depending on trout life history stage, we developed seasonal biomass variation models for three periods of the year (Autumn-Winter, Spring and Summer). Because stream water temperature is a critical parameter for brown trout development, we first calibrated a model to predict water temperature as a function of air temperature to be able to further apply climate change scenarios. We then built a model of trout biomass variation by linking water temperature to trout biomass measurements collected by electro-fishing in 21 stations from 2009 to 2011. The different modelling components of our framework had overall a good predictive ability and we could show a seasonal effect of water temperature affecting trout biomass variation. Our statistical framework uses a minimum set of input variables that make it easily transferable to other study areas or fish species but could be improved by including effects of the biotic environment and the evolution of demographical parameters over time. However, our framework still remains informative to spatially highlight where potential changes of water temperature could affect trout biomass. (C) 2015 Elsevier B.V. All rights reserved.-

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Introducción: La determinación del volumen gástrico residual es una práctica frecuente en pacientes críticos, pero hay falta de consenso acerca de la conveniencia de reintroducir o desechar el contenido gástrico aspirado (CGA). Objetivo: Determinar el grado de evidencia científica acerca de la eficacia de 2 intervenciones-reintroducción/rechazo- del CGA en pacientes críticos. Material y métodos: Revisión sistemática de la evidencia disponible acerca de la conveniencia de reintroducir o desechar el CGA. Proceso: a) establecimiento de los criterios de inclusión/exclusión; b) determinación de la estrategia de búsqueda (palabras clave e itinerarios); c) vaciado de las bases de datos: MEDLINE, CINAHL, CUIDEN, IME, SCIELO y COCHRANE. Búsqueda por método indirecto y vaciado manual de índices; d) lectura crítica independiente y contrastada, utilizando la plantilla CASPe, y e) contraste de resultados del análisis crítico. Resultados: Los itinerarios de búsqueda generan más de 800 referencias que, una vez depuradas, permiten seleccionar 54. Después de su lectura, sólo 4 se centran realmente en cuestiones relacionadas con la reintroducción/rechazo del CGA: 2 revisiones, un estudio observacional y un ECA de muestra pequeña. La heterogeneidad de estos estudios no permite emplear técnicas de metaanálisis. Por ello se analizan por separado los resultados de cada estudio. Mediante este proceso se obtiene un resultado final que demuestra un bajo grado de evidencia científica. Conclusiones: Hay escasa evidencia científica acerca de la conveniencia, la seguridad y los beneficios de ambas intervenciones. Es difícil establecer un protocolo de cuidados, por lo que se planteó realizar un estudio experimental para establecer las indicaciones y contraindicaciones de ambas intervenciones.

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Background: The control of gastric residual volume (GRV) is a common nursing intervention in intensive care; however the literature shows a wide variation in clinical practice regarding the management of GRV, potentially affecting patients" clinical outcomes. The aim of this study is to determine the effect of returning or discarding GRV, on gastric emptying delays and feeding, electrolyte and comfort outcomes in critically ill patients. Method: A randomised, prospective, clinical trial design was used to study 125 critically ill patients, assigned to the return or the discard group. Main outcome measure was delayed gastric emptying. Feeding outcomes were determined measuring intolerance indicators, feeding delays and feeding potential complications. Fluid and electrolyte measures included serum potassium, glycaemia control and fluid balance. Discomfort was identified by significant changes in vital signs. Results: Patients in both groups presented similar mean GRV with no significant differences found (p=0.111), but participants in the intervention arm showed a lower incidence and severity of delayed gastric emptying episodes (p=0.001). No significant differences were found for the rest of outcome measurements, except for hyperglycaemia. Conclusions: The results of this study support the recommendation to reintroduce gastric content aspirated to improve GRV management without increasing the risk for potential complications.

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El objetivo es comprobar si el efecto residual inmunodepresor de la ciclofosfamida contribuye a la evocación de la respuesta de anticuerpos condicionada. Se condicionaron ratones no consanguíneos, machos, con el estímulo condicionado sacarina al 0,15% y con el estímulo incondicionado ciclofosfamida, a 50 y 250 mg/kg. A los 4 días del condicionamiento con 50 mg/kg de ciclofosfamida, o a los 14 días del condicionamiento con 250 mg/kg de ciclofosfamida, los ratones se inmunizaron con glóbulos rojos de rata y, a continuación, bebieron la disolución de sacarina. Se comprobó que i) la dosis más baja de ciclofosfamida no generó efecto residual, mientras que la dosis más alta si, y ii) en ningún caso, la presentación de sacarina disminuyó la respuesta de anticuerpos anti-glóbulos rojos de rata. Se concluye que no se produjo condicionamiento de la respuesta de anticuerpos, tanto si el efecto residual de la ciclofosfamida está presente, como si está ausente.

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The use of GFCI, ground-fault circuit interrupter, in the chemical laboratory is described, to improve the electrical safety of equipments such as rotary evaporators and constant temperature baths.

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Kaasutuksen kannattavuus ja toteutustapa on ollut tarkea ja useiden tutkimuksien kohde. Biomassan kaasutuksen ja siina kaytettavien laitteiden nykytila on epavarma. Niinpa lisatutkimukselle ja tarkasteluille on edelleen tarvetta. Tama tyo keskittyy nykyisin kaytettavien kaasutusprosessien ja laitteiden tarkasteluun. Tyossa kaydaan lapi useita uusimpia kaasutusprojekteja ja esitetaan niista tutkimustarpeita. Lisaksi kaasutusprosessissa pitaa saada hallintaan niille tyypillisia ongelmia kuten kaasun puhdistus, kaasun kasittely, biomassan kasittely ja kaasuttimen muuraus, joista esitetaan lisatietoa. Edelleen esitetaan kaasutusprosessien taydellinen luokittelu. On huomattava etta biomassan kaasutusta tarvitaan jotta saadaan toteutettua EUn hahmotteleman ja saataman energiapolitiikan vaatima kasvu ja kehitys.

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Although it is well known that firing biomass fuels leads to increased deposition buildup on heat transfer surfaces in boiler compared with firing coal, existing empirical knowledge about combustion of different types of biofuels is limited. The aim of this study is to give greater awareness and understanding of the circumstances which are able to decrease considerably deposition build up on heat transfer surfaces when firing different types of biofuels. The crucial part of this thesis is experimental investigation of fouling tendency while firing biomass fuels, such as straw, bark, and peat having different chemical composition. In order to give comprehensive overview of ash deposition phenomena the number of not less important issues such as mechanisms of ash deposition, effect of fouling on heat transfer, and design of boilers subjected to ash buildup were examined as well. The answers obtained in this study may be a step towards a better knowledge of firing biofuels as separately as in mixtures, and may provide solutions for successful combustion technique of biomass fuels.