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Efeito de diferentes níveis protéicos e do ácido linoléico conjugado no desempenho, custos de produção e qualidade de carne de frangos de corte / Effect of different protein and conjugated linolenic acid levels in performance, production costs and meat quality of broilersPreviero, Thiago de Campos 23 October 2009 (has links)
O presente trabalho teve como objetivo estudar os efeitos da suplementação de ácido linoléico conjugado (CLA), associada à redução do nível de proteína bruta (PB) da dieta de frangos de corte. No primeiro ensaio, o período experimental transcorreu dos 21 aos 41 dias, quando 1440 machos da linhagem Ross, com mesmo peso inicial, foram distribuídos em delineamento inteiramente casualizado, em esquema fatorial 3x3, sendo três níveis de CLA (0%, 0,5% e 1,0%) e três níveis de PB (19%, 17%, 15%). Houve redução do ganho de peso e aumento da conversão alimentar apenas em função do decréscimo de PB e ambos os fatores elevaram o índice econômico mensurado. Os rendimentos de carcaça inteira e peito diminuíram proporcionalmente a PB da dieta. Houve interação entre CLA e PB para o tamanho do fígado, ambos os fatores elevaram a gordura abdominal. Em relação aos parâmetros analisados em amostras de peito, o pH elevou-se proporcionalmente, em relação a PB, as intensidades de vermelho e amarelo foram modificadas ou pela PB, ou pelo CLA e para a luminosidade houve interação. Quanto ao perfil de ácidos graxos, a PB elevou somente o ácido esteárico e o CLA aumentou os ácidos graxos saturados e reduziu os monoinsaturados. Houve incorporação crescente dos isômeros de CLA, em função da maior inclusão do produto nas dietas com 19% ou 17% de PB. Nas dietas com 15% de PB, ocorreu um limite máximo para a incorporação do CLA. No segundo experimento, utilizando 144 aves Ross e mesmo delineamento e modelo experimental, houve efeito quadrático da PB para o balanço de nitrogênio e interação entre CLA e PB para a digestibilidade da PB dietária. / The objective of this research was to study the effects of the conjugated linoleic acid, known as CLA, associated with reduction of crude protein (CP) level in broiler diets. At first assay, the period of experiment was conducted from 21 to 41 days, when 1440 male broilers from Ross line, with the same weight initial, were allocated in accordance to a completely randomized design, with factorial model 3x3, corresponding in 3 CLA inclusions levels (0%, 0,5% and 1,0%) and 3 CPs levels (19%,17%,15%). Weight gain reduction and increased feed conversion were only related to decrease of CP inclusion and both of factors, CP and CLA inclusion levels, elevated the economic index parameters. Carcass and breast meat yields decreased due to the reduction of CP addition in diets. The interaction between CLA and CP factors modified in liver size, and both elevated the abdominal fat percents. In relation to parameters analyzed in breast samples, the pH elevated proportionally to CP inclusion, the redness and yellowness were modified by CP or CLA addition and interaction of both were detected to luminosity parameter. About fatty acid composition, the addition of CP only elevated the stearic acid and CLA inclusion improved the saturated fatty acid levels and reduced the monounsaturated fatty acid levels. An improvement on incorporation of CLA isomers was verified due to more inclusion of this product in 19% or 17% CPs diets. In the case of 15% CPs diets, the incorporation of CLA isomers had a maxim limit. In the second assay, using 144 Ross line broilers with the same design and model, a quadratic effect for nitrogen balance was verified due to CP diets and an effect of interaction between CLA and CP inclusion was found to digestibility of dietary CP.
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Elementos traço em óleo cru: determinação total e estudo de especiação / Trace elements in crude oil: total determination and speciation studyMaciel Santos Luz 17 December 2013 (has links)
O objetivo desta pesquisa foi o desenvolvimento de métodos para: determinação simultânea de Cr/Fe/Ni/V em óleo cru; determinação simultânea de Co/Cu/Pb/Se em óleo cru, gasolina e diesel; determinação monoelementar de Si em óleo cru, gasolina e diesel; e determinação de espécies porfirínicas de Fe/Ni/V em óleo cru, utilizando ultracentrifugação e extração em ponto nuvem, por espectrometria de absorção atômica com forno de grafite e detecção simultânea (SIMAAS). Foram estudadas as condições de preparo das amostras por emulsão, empregando Triton X-100® como surfactante e hexano ou clorofórmio como solventes diluentes do óleo cru. Nas melhores condições, as emulsões foram preparadas em 6% (m v-1) de Triton X-100® com o óleo cru previamente diluído com 125 µL de hexano (nos métodos para as determinações totais dos elementos) ou diluído com 400 µL de clorofórmio (no método para a determinação das espécies porfirínicas). No método envolvendo a determinação simultânea total de Cr/Fe/Ni/V não foi utilizada agitação ultrassônica devido à pequena massa de óleo necessária (50 mg) para análise. Por outro lado, a agitação ultrassônica foi essencial para possibilitar a estabilização de maiores massas de óleo cru (200 mg e 400 mg) na emulsão. A estabilidade da emulsão só foi melhorada com agitação ultrassônica, antes da etapa de diluição com água. Nessa condição, foi possível obter emulsões estáveis com 200 mg ou 400 mg de óleo cru, por 30 min ou mais de 8 h, respectivamente. O programa de aquecimento do forno de grafite foi avaliado em cada caso, com e sem uso de diferentes modificadores químicos (Pd e Mg), especialmente nos métodos de determinação simultânea, em que foi necessário adotar condições de compromisso. Para a determinação monoelementar de Si foi verificado melhora nos parâmetros analíticos (sensibilidade e repetibilidade) com o uso de NbC como modificador permanente combinado com 20 µg de Pd como modificador químico co-injetado. Os LODs estimados para Cr (0,07 µg g-1), Fe (2,15 µg g-1), Ni (1,25 µg g-1), V (1,25 µg g-1), Co (0,02 µg g-1), Cu (0,03 µg g-1), Pb (0,04 µg g-1), Se (0,11 µg g-1) e Si (0,16 µg g-1) foram suficientemente baixos para permitir as determinações dos elementos com boas precisão e exatidão. Análises de materiais de referência forneceram resultados a um nível de confiança de 95%, quando aplicado o teste t>/i> de Student. O fracionamento de porfirinas de Fe/Ni/V foi feito em emulsão de óleo cru combinando com a extração por ponto nuvem (CPE) e ultracentrifugação. Nesse estudo, foi verificado a necessidade do uso de 0,1 mol L-1 de HCl para extração dos elementos associados a espécies organometálicas não porfirínicas. Após a ultracentrifugação da emulsão de óleo cru, os alfaltenos e material particulado foram separados e no sobrenadante permaneceram espécies inorgânicas, compostos organometálicos leves e porfirinas de Fe, Ni e V. Após CPE de outra emulsão de óleo cru permaneceram na fase aquosa espécies inorgânicas e composto organometálicos leves. As concentrações das porfirinas de Fe, Ni e V foram determinadas após a subtração dos resultados obtidos no primeiro (ultracentrifugação) e segundo (CPE) procedimentos. / The objective of this research was the methods development for: simultaneous determination of Cr/Fe/Ni/V in crude oil; simultaneous determination of Co/Cu/Pb/Se in crude oil, gasoline and diesel; determination of Si in crude oil, gasoline and diesel; and determination of porphyrin species of Fe/Ni/V in crude oil using graphite furnace atomic absorption spectrometry with simultaneous detection (SIMAAS). It was studied the conditions for the emulsion sample preparation, employing Triton X-100® as surfactant and hexane or chloroform as diluent of the crude oil. Under the best conditions, the emulsions were prepared in 6% (m v-1) of Triton X-100® with crude oil previously diluted with 125 µl of hexane (in methods for total determination of elements) or diluted with 400 µl of chloroform (in the method for determination of porfhyrin species). In the method for the simultaneous determination of Cr/Fe/Ni/V it was not necessary to use ultrasonic agitation due to the small mass of oil needed (50 mg) for analysis. On the other hand, ultrasonic agitation was essential to enable the stabilization of larger masses of crude oil (200 mg and 400 mg) in emulsion. The emulsion stability was improved with ultrasonic agitation, before dilution step with water. In this condition, it was possible to obtain stable emulsions with 200 mg or 400 m;g of crude oil, for 30 min or more than 8 h, respectively. The heating program of graphite furnace was evaluated in each case, with and without use of different chemical modifiers (Pd and Mg), especially in the methods for simultaneous determination, in which was necessary to adopt compromise conditions. For Si determination, was verified significant improvement in analytical parameters (sensitivity and repeatability) with the use of NbC as permanent modifier, combined with co-injected 20 µg of Pd as chemical modifier. The LODs estimated for Cr (0.07 µg g-1), Fe (2.15 µg g-1), Ni (1.25 µg g-1), V (1.25 µg g-1), Co (0.03 µg g-1), Cu (0.03 µg g-1), Pb (0.04 µg g-1), Se (0.11 µg g-1) and Si (0.16 µg g-1) were low enough to allow measurements of the elements with great precision and accuracy. Analysis of reference materials provided results at confidence level of 95%, when applied to the Student\'s t-test. The Porphyrin fractionation of Fe/Ni/V was done on crude oil emulsion by combining cloud point extraction (CPE) and ultracentrifugation. In this method, 0.1 mol L-1 of HCl must be used for extraction of elements associated with the organometallic species different of porfhyrins. After the ultracentrifugation of crude oil emulsion, asfalthene and particulate matter were separated and in the supernatant remained inorganic species, organometallic compounds and porphyrins of Fe, Ni and V. After CPE of another emulsion of crude oil, remained in the aqueous phase only the inorganic and organometallic compound species. The porphyrin concentrations of Fe, Ni and V were determined after the subtraction of the results obtained in the supernatant from the first (centrifugation) and second (CPE) procedures.
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Optimisation-based retrofit of heat-integrated distillation systemsEnriquez Gutierrez, Victor Manuel January 2016 (has links)
Distillation systems consist of one or more distillation columns, in which a mixture is separated into higher-value products, and a heat exchanger network (HEN) that recovers and reuses heat within the system. For example, crude oil distillation systems comprise crude oil distillation units (CDU), in which crude oil is distilled into products for downstream processing, a HEN and a furnace. Heat-integrated distillation systems present complex interactions between the distillation columns and HEN. These interactions, together with the many degrees of freedom and process constraints, make it challenging to retrofit or modify the operating conditions of existing distillation processes to accommodate changes in process operating conditions. Retrofit designs aim to re-use existing equipment when process objectives change, for example to increase throughput, improve product quality, or reduce energy consumption or environmental impact. To achieve these retrofit objectives, operational, structural and/or flowsheet modifications to the overall system (distillation columns and HEN) may be considered, subject to specifications and system constraints. This work proposes an optimisation-based approach to retrofit design for the capacity expansion of heat-integrated distillation systems, with a particular focus on crude oil distillation systems. Existing retrofit approaches found in the open research literature consider operational optimisation, replacing column internals, adding preflash or prefractionation units and HEN retrofit to increase the capacity of existing systems. Constraints considered usually relate to the distillation column hydraulic limits, product quality specifications and heat exchanger performance (e.g. minimum temperature approach and, pressure drop). However, no existing methodologies consider these possible modifications simultaneously; thus, beneficial interactions between flowsheet modifications, operational changes, heat integration and equipment modifications may be missed. In this work, retrofit design solutions for crude oil distillation are developed using a stochastic optimisation framework implemented in MATLAB to optimise the system operating parameters and to propose flowsheet, column and HEN modifications. Within the framework, the optimiser can propose addition of a preflash unit, modifications to the CDU internals and changes to its operating conditions; the separation system is then simulated using Aspen HYSYS (via the MATLAB interface) and the hydraulic performance of the column is analysed using published hydraulic correlations. The optimiser also proposes modifications to the HEN (i.e. installed heat transfer area, HEN structure and operating conditions), which is then simulated to evaluate heating and cooling utility demand. Either simulated annealing and global search optimisation algorithms are applied to identify the optimal design and operating conditions that meet the production requirements and product specifications. Industrially relevant case studies demonstrate the effectiveness and benefits of using the proposed retrofit approach. The case studies illustrate that combined structural and operational modifications can be effectively and systematically identified to debottleneck an existing crude oil distillation system with a relatively short payback time, while simultaneously reducing energy consumption per barrel of crude oil processed.
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Unravelling the chemistry behind the toxicity of oil refining effluents : from characterisation to treatmentPinzón-Espinosa, Angela January 2018 (has links)
Adequate wastewater management is a crucial element to achieve water sustainability in the petroleum refining sector, as their operations produce vast quantities of wastewater with potentially harmful contaminants. Treatment technologies are therefore pivotal for stopping these chemicals from entering the environment and protecting receiving environments. However, refining effluents are still linked to serious pollution problems, partly because little progress has been made in determining the causative agents of the observed biological effects, resulting in non-targeted treatment. Here it is shown that naphthenic acids, which have been reported as toxic and recalcitrant, are important components of refining wastewater resulting from the processing of heavy crude oil and that they have a significant contribution to the toxic effects exerted by these effluents. Furthermore, it was found that their chemical stability makes them highly resistant to remediation using Pseudomonas putida and H2O2/Fe-TAML (TetraAmido Macrocyclic Ligands) systems under laboratory conditions, and only sequential aliquots of Fe-TAML catalysts and H2O2 showed to partially degrade naphthenic acids (50 mg/L) within 72 hours. Results suggest that a combinatorial approach of Fe-TAML/H2O2 followed by biodegradation might improve current treatment options, but further optimisation is required for the biological treatment. These results can serve as a starting point for better environmental regulations relevant to oil refining wastewater resulting from heavy crude oil, as naphthenic acids are not currently considered in the effluent guidelines for the refining sector. Furthermore, the degradation of naphthenic acids under mild conditions using Fe-TAML/H2O2 systems indicates that these catalysts hold promise for the remediation of refining wastewater in real-life scenarios.
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Asset price and volatility forecasting using news sentimentSadik, Zryan January 2018 (has links)
The aim of this thesis is to show that news analytics data can be utilised to improve the predictive ability of existing models that have useful roles in a variety of financial applications. The modified models are computationally efficient and perform far better than the existing ones. The new modified models offer a reasonable compromise between increased model complexity and prediction accuracy. I have investigated the impact of news sentiment on volatility of stock returns. The GARCH model is one of the most common models used for predicting asset price volatility from the return time series. In this research, I have considered quantified news sentiment as a second source of information and its impact on the movement of asset prices, which is used together with the asset time series data to predict the volatility of asset price returns. Comprehensive numerical experiments demonstrate that the new proposed volatility models provide superior prediction than the "plain vanilla" GARCH, TGARCH and EGARCH models. This research presents evidence that including news sentiment term as an exogenous variable in the GARCH framework improves the prediction power of the model. The analysis of this study suggested that the use of an exponential decay function is good when the news flow is frequent, whereas the Hill decay function is good only when there are scheduled announcements. The numerical results vindicate some recent findings regarding the utility of news sentiment as a predictor of volatility, and also vindicate the utility of the new models combining the proxies for past news sentiments and the past asset price returns. The empirical analysis suggested that news augmented GARCH models can be very useful in estimating VaR and implementing risk management strategies. Another direction of my research is introducing a new approach to construct a commodity futures pricing model. This study proposed a new method of incorporating macroeconomic news into a predictive model for forecasting prices of crude oil futures contracts. Since these futures contracts are iii iv more liquid than the underlying commodity itself, accurate forecasting of their prices is of great value to multiple categories of market participants. The Kalman filtering framework for forecasting arbitrage-free (futures) prices was utilized, and it is assumed that the volatility of oil (futures) price is influenced by macroeconomic news. The impact of quantified news sentiment on the price volatility is modelled through a parametrized, nonlinear functional map. This approach is motivated by the successful use of a similar model structure in my earlier work, for predicting individual stock volatility using stock-specific news. Numerical experiments with real data illustrate that this new model performs better than the one factor model in terms of accuracy of predictive power as well as goodness of fit to the data. The proposed model structure for incorporating macroeconomic news together with historical (market) data is novel and improves the accuracy of price prediction quite significantly.
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Modelování společného pohybu cen na energetickém trhu / Crude oil co-movement with other representatives of energy and non-energy commodity marketsMustivaya, Julia January 2012 (has links)
Financialization of crude oil and its frequent inclusion into investment portfo- lios raise the demand for proper correlation estimates of this commodity and other financial assets. This thesis particularly examines the co-movement of crude oil price with prices of four other representatives of commodity market (gasoline, natural gas, gold and Industrials Index). It contributes to the exist- ing literature by the results obtained from application of wavelet coherence, which allows uncovering dynamics of interconnection between commodity prices in time as well as over different frequencies. Analysis brings many in- teresting findings and practical implications. Among others, it specifies the investment horizons that should be considered to maximize diversification properties of studied commodities. 1
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Análise do processo de dessalgação de petróleo - otimização do uso de água. / Process analysis of crude oil desalting - water uses optimization.Antonio Esio Bresciani 19 May 2009 (has links)
Este trabalho visa o estudo da viabilidade da redução do uso de água no processo de dessalgação em refinarias de petróleo. Em uma primeira fase, foi necessário o estudo teórico da separação das emulsões água/óleo. Em seguida, foi desenvolvido um modelo matemático baseado nas forças atuantes nas gotas de água, o que possibilitou a determinação do tempo entre as colisões de pares de gotas e o estabelecimento do critério para que ocorra o fenômeno de coalescência. Esse modelo foi empregado em um sistema desenvolvido com base em autômatos celulares, o qual possibilitou o acompanhamento do processo micro e macroscópico, através do cálculo para o conjunto das gotas, e o acompanhamento visual até a separação da fase contínua. Os experimentos de laboratório, para os quais foi usado equipamento ótico para a medição da intensidade de luz transmitida ou espalhada pelas gotas, possibilitaram avaliar a influência da qualidade da água de mistura no tempo de separação das emulsões. Na unidade industrial, foram realizados testes que permitiram analisar o desempenho das dessalgadoras em diferentes situações operacionais. Os resultados obtidos através dos experimentos de laboratório e da simulação usando o modelo matemático desenvolvido mostraram-se compatíveis com os dados obtidos nos testes na unidade industrial. O trabalho mostrou ser possível alterar os esquemas de usos de água nas dessalgadoras, aumentando a taxa de reciclagem e possibilitando a otimização do consumo de água fresca neste processo, o que resultaria em redução substancial no consumo geral de água na refinaria. / The aim of this work is the study of the reduction of water consumption in petroleum desalting processes. The study of the attraction forces acting on the droplets was necessary to know how the emulsion water/oil is separated. A mathematical model based upon these forces was built to calculate the time between each droplets collision and to establish criteria for their coalescence. This model was applied to a system developed based on cellular automata, which allows to follow the process micro and macroscopically. Computations were carried out to the ensemble of droplets and the visual progression, from the start of droplets separation of the continuous phase to the end of the process could be visualized. Laboratory experiments, in which optical equipment was used to measure the light intensity transmitted or scattered by the droplets, allowed to evaluate the influence of the type of mixing water in the separation time of the emulsions. Tests in the industrial unity allowed evaluating the performance of the desalting units at different operating conditions. Conclusions of the laboratory experiments and the results of the mathematical model were compared with results of the industrial tests, showing coherence between them. The work shows that it is possible to simulate the effect of the operating variables and to alter schemes of water use in desalting units, increasing the water recycling rate, allowing optimization of fresh water consumption in this process and reducing the total water consumption in the refinery.
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Biomassa, eficiência de conversão, recuperação aparente de nitrogênio e composição bromatológica da silagem de cultivares de milheto submetidos à adubação nitrogenada / Biomass, conversion efficiency, apparent recovery of nitrogen and chemical composition of silage of cultivars of millet submitted the nitrogen fertilizationSilva, Nelson Rafael da 02 December 2013 (has links)
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Previous issue date: 2013-12-02 / This study aimed to evaluate the production of green mass (MV), dry matter (DM), nitrogen contained in the plant (NC), conversion efficiency of nitrogen (ECAN), apparent recovery of nitrogen (RAN) and chemical characteristics of pearl millet [Pennisetum glaucum (L.) R. Br]: ADR-500, ADR 7020 and LABH 70732, in doses of N: (0, 50, 100 and 200 kg ha-1), cut at 87 days of vegetative growth, aiming to the silage production. The experimental design used
randomized blocks in a 3x4 factorial design (three cultivars and four doses of N), with four replications. Regarding biomass, only the green mass production (MV) showed interactions between N and millet cultivars, ranging from 30.54 to 50.96 t ha-1 of MV. The dry mass production (P>0.05) showed interaction only amongst the N dose, ranging from 7.66 to 12.46 t ha-1. The conversion efficiency of N (ECAN) and apparent recovery of N (NRE) differed (P<0,05) among the doses and the millet cultivars, with decreasing average values due to the increase of nitrogen fertilization. The best conversion efficiency was 54.06 kg DM / kg of N applied, while the highest N recovery rate was 86.54%, both at equivalent dose of the application of 50 kg.ha-1 of N. Among the millet cultivars, significant statistical differences have been observed on the nitrogen contained in the plant in unfertilized plots, ranging from 103.64 kg ha-1 (ADR 500) to 135.69 kg ha-1 (LABH 70732). In fertilized plots cultivars (P>0.05) in NC levels. The ECAN and NRE (P<0.05) among the millet cultivars with average values of 43.34 kg DM / kg of N applied (ADR 500) and 78.76% of N recovered,
also with the same cultivar. The variable components of the chemical composition did not differ due to the evaluated N doses, with the average values of: DM - 25.40%; CP - 9.54%; NDF - 62.5%; ADF - 34.13%; HEM - 28.35%; CEL - 29.29%; LIG - 6.68%;NFC - 17.32%, OM - MM and 90.75% - 9.22%. / Objetivou-se avaliar a produção de massa verde (MV), massa seca (MS), a composição bromatológica, eficiência de conversão de nitrogênio (ECAN), recuperação aparente do nitrogênio (RAN) de cultivares de milheto (ADR-500, ADR 7020 e LABH 70732, sob doses de N: (0, 50, 100 e 200 kg ha-1), cortado aos 87 dias de crescimento vegetativo, visando a produção de silagem. O delineamento experimental utilizado foi o de blocos casualizados em esquema fatorial 3x4 (três cultivares e quatro doses de N), com quatro repetições. A
produção de massa verde (MV) apresentou interações entre doses de N e cultivares de milheto, com variação de 30,54 a 50,96 t ha-1 de MV. A produção de massa seca (P>0,05) apenas entre as dose de N, com variação de 7,66 a 12,46 t ha-1. A eficiência (P<0,05) de conversão de N (ECAN) e a recuperação aparente de N (RAN) diferiram entre as doses de N e cultivares de milheto, com valores médios decrescentes, em função do acréscimo da adubação nitrogenada. A melhor eficiência de conversão foi de 54,06 kg de MS/kg de N
aplicado, enquanto a mais alta taxa de recuperação de N foi de 86,54%, ambos na dose equivalente a aplicação de 50 kg ha-1 de N. Dentre os cultivares de milheto foram observadas diferenças significativas no teor de nitrogênio contido (NC) na planta nas parcelas não adubadas, com variação de 103,64 kg ha-1
(ADR 500) a 135,69 kg ha-1 (LABH 70732). Nas parcelas adubadas os cultivares (P>0,05) nos teores de NC. A ECAN e a RAN (P<0,05) entre os cultivares de milheto com valores médios de 43,34 kg MS kg-1 N aplicado (DAR 500) e 78,76%, de N recuperado, também com o mesmo cultivar. As variáveis componentes da composição bromatológica não diferiram em função das doses de N avaliadas, cujos valores médios foram: MS – 25,40%; PB – 9,54%; FDN – 62,5%; FDA – 34,13%; HEM – 28,35%; CEL – 29,29%; LIG – 6,68%;
CNF – 17,32%; MO – 90,75% e MM – 9,22%.
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Efeito do tratamento de cama e de estratégias nutricionais sobre índices produtivos e qualidade de carne em frangos de corte / Poultry litter treatment and nutritional strategies effects on productive indexes and meat quality in broiler chicksFurlan, Joyce de Jesus Mangini 11 August 2017 (has links)
Objetivou-se avaliar os efeitos do uso de sulfato de alumínio, da densidade de alojamento e de estratégias nutricionais sobre índices produtivos, econômicos e qualidade de carne na produção de frangos de corte. Foram conduzidos dois experimentos, nos quais: Experimento I (EI) Objetivou-se avaliar os efeitos das doses de sulfato de alumínio [Al2(SO4)3 18 H2O] - (0, 200, 400 e 600 g/m2) no tratamento da cama aviária e da taxa de lotação (8 e 9 aves/m2). Foi avaliadas na cama, a amônia volatilizada, pH, teor de matéria-seca e nitrogênio, além do desempenho das aves, rendimento de carcaça, cortes (peito e coxa-sobrecoxa), ocorrência de lesão de peito e pododermatite e qualidade da carne (pH, cor, perdas totais por cozimento, maciez objetiva e análise sensorial). No Experimento II (EII) os objetivos foram avaliar os efeitos da inclusão dietética de fitase (1.000 FTU/kg de ração) e da redução do nível de proteína bruta (um ponto percentual) nas dietas de frangos criados em cama tratada ou não com sulfato de alumínio (1.568 g/m2). Além das análises citadas anteriormente, objetivou-se avaliar o aspecto microbiológico das carcaças de frango e propor uma estimativa econômica do poder fertilizante da cama aviária. Foi realizada a análise da viabilidade econômica do uso do sulfato de alumínio, da fitase e da redução do nível proteico da dieta na produção avícola. (EI) As doses de sulfato de alumínio e as taxas de lotação influenciaram as características da cama, reduzindo os valores de pH e minimizando a quantidade de amônia volatilizada. A melhor dose de sulfato de alumínio foi de 400 g/m2 independente da lotação adotada. As doses de sulfato de alumínio avaliadas não influenciaram o desempenho das aves, que foi afetado negativamente pelo aumento da densidade. Observou-se efeito significativo da interação sulfato de alumínio × taxa de lotação (P = 0,0094) sobre o rendimento de carcaça. O teste afetivo mostrou que o sulfato de alumínio não influenciou a aceitabilidade dos consumidores pela carne de frango. A análise economica demonstrou que a margem bruta aumentou quando a lotação foi de nove aves/m2 já que o peso do lote é maior. (EII) A aplicação do sulfato de alumínio na cama aviária reduziu os valores de pH e consequentemente a amonia volatilizada. Além disso, a baixa PB e a fitase reduziram o pH e a amônia também. O sulfato de alumínio (1.568 g/m2) reduz a emissão de amônia e as perdas de N da cama. Valorar o dejeto avícola como fertilizante orgânico permite uma melhor decisão com relação às quantidades a serem aplicadas na lavoura, promovendo benefícios econômico e ambiental. A inclusão dietética de fitase (1.000 FTU/kg de ração) influenciou características de cor da carne e melhorou sua maciez segundo a percepção de consumidores não treinados. O uso de 1.568 gramas de sulfato de alumínio por m2 diminui a margem de comercialização, onerando os custos de produção. Além disso, pode-se concluir que as diferentes estratégias nutricionais não apresentaram diferenças nas margens de comercialização, indicando a viabilidade econômica na utilização de ferramentas nutricionais para manutenção do impacto ambiental da produção avícola. / The aim of this study was to evaluate the effects of the use of aluminum sulfate, stocking density and nutritional strategies on productive, economic indexes and meat quality on poultry industry. Therefore, two experiments were conducted. Experiment I (EI) the aim of study was to evaluate the effects of aluminum sulfate doses [Al2(SO4)3·18H2O] - (0, 200, 400 e 600 g/m2) to treated poultry litter and bird densities (8 and 9 birds/m2). It was evaluated volatilized ammonia, pH values, dry matter and nitrogen content from poultry litter. Furthermore, it was evaluated live performance, carcass, breast, drumstick and thigh yield, prevalence of breast skin lesions and foot-pad dermatitis, and chicken meat quality (pH, color, shear force, cook loss and sensorial analysis). Experiment II (EII) aims evaluate the effects of aluminum sulfate to treat litter (0 or 1.568 g/m2), including phytase (1,000 FTU/kg of feed) in the diet and diets with low-crude protein (one percentage point of reduction). This study aims to evaluate the Microbiological Plate Counts on carcasses was evaluated and propose a method to value the manure in relation to its potential as fertilizer too. The economic analysis was also performed, considering the use of aluminum sulphate, phytase and diets with low-crude protein in the production of broiler chickens. The economic analysis the marketing margin increased when the density was 9/m2 because the sold broilers weight was higher. (EI) Aluminum sulfate doses and the stocking density influence poultry litter characteristics, lowering the pH values and reducing the amount of volatilized ammonia. The best dose of aluminum sulphate was 400 g/m2 regardless of the density adopted. The use of aluminum sulfate doses evaluated did not influence the broiler performance, which was negatively affected by the increase in the density. A significant effect of the interaction (P = 0.0094) was verified for carcass yield. The affective test showed that aluminum sulfate didnt influence consumers acceptability for chicken meat. The economic analysis showed that the contribution margin increased when the stocking was 9 birds/m2 since the lot weight is higher. (EII) Application of alum to the litter lowered pH values and consequently ammonia volatilization, moreover the low crude protein and phytase reduced this traits too. Aluminum sulfate (1.568 g/m2) reduces ammonia emissions and consequently nitrogen losses from litter. Valuing poultry manure as organic fertilizer allows the better decision in relation to the quantity to be applied to the crop, promoting economic and environmental benefits. It was concluded that the inclusion of phytase (1,000 FTU/kg of feed), influences chicken meat color characteristics, and improved meat tenderness in the perception of untrained panelists. The use of 1,568 grams of aluminum sulphate per m2 decreased the marketing margin, inflating production costs. In addition, it can be concluded that different nutritional strategies did not present differences in the margins of commercialization, indicating the economic feasibility in the use of nutritional tools to maintain the environmental impact of poultry production.
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Investigation of the probable anti-cancer effects of the crude methanol extract of dicerocaryum senecioides, (Klotzch) J. Abels, leaves on cervical HeLa cancer cellMalemela, Kholofelo Mmanoko January 2018 (has links)
Thesis (M.Sc. (Biochemistry) -- University of Limpopo, 2018 / Dicerocaryum senecioides is a plant widely used as a nutritional source. It is used also for treatment of measles, wounds and to facilitate birth in domestic animal and humans in many parts of southern Africa (Mampuru et al., 2012). Findings in our laboratory have shown that a dichloromethane fraction of D. senecioides possesses antiinflammatory properties in human t-lymphocytes (Madiga, 2009), while the methanol crude extract possesses anti-proliferative and proapoptotic properties against Jurkat T cancer cells (Mphahlele, 2008). In this study, the probable anti-cancer effect of D. senecioides crude methanol leaf extract was investigated on cervical HeLa cancer cells. Dried powdered leaves of D. senecioides were extracted with absolute methanol to obtain a crude extract. To assess the cytotoxicity effect of the extract, KMST-6 and HeLa cell cultures were exposed to various extract concentrations (0 to 600 µg/ml) for 24 and 48 hours and subjected to the MTT assay. The results showed the extract to have no significant increase in the viability inhibition of HeLa cells at all tested concentrations after 24 hours of treatment. However, treatment with 400, 500 and 600 µg/ml of the extract for 48 hours revealed significantly increased HeLa cell viability inhibition. Furthermore, the extract showed to have no effect on the viability of normal human fibroblast KMST-6 cells at concentrations below 600 µg/ml, after 24 and 48 hours of treatment, thus showing selective cytotoxicity of the extract. To determine the mode of cell death associated with the increase in HeLa cell viability inhibition, the Hoechst 33258 nuclear staining assay and inverted light microscopy were employed. The data proposed apoptosis as the mode of cell death associated with the inhibition of HeLa cell viability. This was evidenced by changes in cell morphology such as the loss of HeLa cell radial extensions, cell shrinkage, as well as nuclear morphological features such as chromatin condensation. Apoptosis induction was further confirmed by the annexin-V/PI and multicaspase assays, using flow cytometry. The results showed an increase in the percentage of cells stained with annexin-V/PI, as well as increased caspase activity in extract-treated HeLa cells. To elucidate proapoptotic mechanisms of the extract, Western blotting analysis as well as the human apoptosis antibody array kit were used. This was to measure the expression profile of a number of apoptosis regulatory proteins. The results demonstrated modulation of some anti- and pro-apoptotic proteins, as well as the release of mitochondrial proteins required
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for initiation of apoptosis, in the cytoplasm. The D. senecioides extract showed to have no effect on the cell division cycle of HeLa cells as determined by the PI staining assay. In conclusion, D. senecioides crude methanol leaf extract induced some degree of apoptosis in cervical HeLa cancer cells via the intrinsic apoptosis pathway. This was by modulating some of the members of the Bcl-2 family of proteins, which, facilitated the release of cytochrome C and activation of a caspase cascade. / South African Medical Research Council (SAMRC)
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