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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

Glicerina bruta em dietas para bovinos da raça Nelore confinados

Van Cleef, Eric Haydt Castello Branco [UNESP] 01 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-01Bitstream added on 2014-06-13T20:24:27Z : No. of bitstreams: 1 vancleef_ehcb_dr_jabo.pdf: 716188 bytes, checksum: 56562a9c8c0179eb57647b94dea7b437 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivou-se neste estudo avaliar a inclusão de glicerina bruta em dietas para bovinos da raça Nelore e seu efeito sobre o comportamento ingestivo, consumo, desempenho, parâmetros sanguíneos, características de carcaça e carne, digestibilidade, degradabilidade, parâmetros ruminais, produção de CH4 e CO2 e da massa microbiana. Cinco dietas experimentais foram testadas: G0 - controle sem adição de glicerina, G7,5 - 7,5% de glicerina na matéria seca da dieta, G15 - 15% de glicerina na matéria seca da dieta, G22,5 - 22,5% de glicerina na matéria seca da dieta e G30 - 30% de glicerina na matéria seca da dieta. No primeiro experimento foram utilizados bovinos (n=30, machos, não castrados, raça Nelore, 277,7kg PC, 18 meses de idade) distribuídos em delineamento em blocos ao acaso. Foram avaliados, durante 103 dias de confinamento, o consumo de MS e de nutrientes, GMD, CA, EA, além do comportamento ingestivo. No segundo experimento foram avaliados os parâmetros sanguíneos dos animais do confinamento e pesos de carcaça quente e fria, rendimento de carcaça, AOL, GSUB, além da composição centesimal, perfil de AG, colesterol e análise sensorial da carne. No terceiro experimento foram avaliadas as digestibilidades da MS e de nutrientes e a degradabilidade ruminal dos ingredientes utilizados. Para as incubações ruminais foram utilzados bovinos (n=5, machos castrados, raça Nelore, 400kg PC, 24 meses de idade) dotados de cânulas ruminais permanentes e distribuídos em delineamento em quadrado latino (5 × 5). No quarto experimento foram avaliados pH, N-NH3, AGCC, produção de CH4 e CO2, além das bactérias sólido-aderidas e bactérias e protozoários líquido associados. A inclusão de até 30% de glicerina deprimi a digestibilidade e degradabilidade da fibra, diminui a produção de CH4 e CO2 e interfere negativamente na produção... / The objective of this study was to evaluate the inclusion of crude glycerin in diets for Nellore cattle and its effect on ingestive behavior, intake, performance, blood parameters, characteristics of carcass and meat, digestibility, degradability, ruminal parameters, production of CH4 and CO2 and microbial mass. Five experimental diets were tested: G0 - control without addition of glycerin, G7, 5 - 7.5% glycerin in the diet dry matter, G15 - 15% glycerin in the diet dry matter, G22, 5 - 22.5% glycerin in the diet dry matter and G30 - 30% glycerin in the diet dry matter. In the first experiment bovine (n=30, steers, Nellore, BW 277.7 kg, 18 months old) distributed in a randomized block design were used. It was evaluated during 103 days of feedlot, DM and nutrient intake, ADG, G:F, F:G, and ingestive behavior. The second experiment evaluated the blood parameters of animals in the feedlot, hot and cold carcass weights, LM, SF, and the proximate composition, fatty acid profile, cholesterol and sensory analysis of meat. In the third experiment it was evaluated the dry matter and nutrient digestibility and ingredients degradability. For rumen incubations, cattle (n=5 steers, Nellore, BW 400kg, 24 months old) fitted with permanent ruminal cannulas and distributed in Latin square design (5 × 5) were used. In the fourth experiment it was evaluated pH, N-NH3, SCFA, production of CH4 and CO2, in addition to the particle-associated bacteria and liquid-associated protozoa and bacteria. The inclusion of up to 30% glycerin depresses fiber digestibility and degradability, decreases production of CH4 and CO2 and has negative impact on the production of particle-associated bacteria, and it does not promote changes in performance variables... (Complete abstract click electronic access below)
252

Experiments on EHD injection, interaction and electrocoalescence of water droplet pairs in oil / Étude expérimentale de l'injection EHD, l’interaction et l'électrocoalescence de deux gouttelettes d'eau dans l'huile

Xia, You 18 July 2016 (has links)
Lorsque des champs électriques sont appliqués à des mélanges eau-huile, les petites gouttelettes d'eau sont attirées entre elles et se regroupent en gouttes plus grosses. Ce processus d’électrocoalescence rend plus efficace la séparation huile-eau par sédimentation.Des données expérimentales sur l’électrocoalescence de très petites gouttelettes sont nécessaires pour améliorer la compréhension de la dynamique de l'interface eau-huile et pour valider les modèles numériques. La configuration simple étudiée dans ce travail de thèse concerne une petite paire de gouttelettes tombant dans une cuve d'huile modèle et soumise à un champ électrique aligné avec l’axe de symétrie des gouttes et la gravité.La première partie du travail a consisté à générer de façon contrôlée d’une paire de très petites gouttelettes (dans la gamme de diamètres 20-200 microns) alignée avec le champ électrique. La génération de goutte à la demande, par méthode éléctrohydrodynamique (EHD) a été améliorée pour un meilleur contrôle du diamètre et de la charge électrique des gouttelettes injectées à partir d'une aiguille métallique unique. Ceci a été obtenu en appliquant à un ménisque d'eau pendant à l’extrémité de l’aiguille des impulsions électriques de forme optimisée.La caractérisation électrique et hydrodynamique des paires de gouttelettes et leur coalescence sont alors principalement déduites de l'analyse des vitesses de chute, avec et sans application d’un champ électrique à courant continu. Des données complètes de positions des gouttelettes et de leur vitesse en fonction du temps sont déduites de prises de vues vidéo. Une attention particulière a été accordée aux visualisations de très petites gouttelettes tombant à petites vitesses, associant des angles multiples de prise de vue, de forts zooms et des vidéos à grande vitesse.La modélisation des différents termes d'interactions hydrodynamiques et électrostatiques entre les gouttelettes permet de déduire des vitesses enregistrées leur masse charge électrique respectives. Quand se produit une coalescence des deux gouttelettes, un enregistrement de la vitesse de la gouttelette résultante, avec et sans tension électrique appliquée, permet de contrôler la conservation de la masse et de la charge électrique, et la validation du procédé.Un premier ensemble de données est constitué d'environ 70 cas différents, avec différentes paire des gouttelettes (dans une plage de diamètre limitée de façon à ce que les vitesses de chute soient comprises entre 0,1 et 0,3 mm/s) et en faisant varier la tension appliquée à courant continu ou alternatif. L'analyse des résultats et des incertitudes expérimentales et un exemple de comparaison possible avec des simulations numériques utilisant le logiciel Comsol Multiphysics ™, permettent d'effectuer des recommandations pour les travaux futurs.Ce travail a été financé par le projet “Fundamental understanding of electrocoalescence in heavy crude oils”; coordonné par SINTEF Energy Research. Le projet a été soutenu par The Research Council of Norway, dans le cadre du contrat n °: 206976 / E30, et par les partenaires industriels suivants: Wärtsilä Oil & Gas Systems AS, Petrobras et Statoil ASA. / When electric fields are applied in oil-water mixtures small water droplets are attracted to others and merge in larger drops. This electrocoalescence process makes more efficient the oil-water separation by sedimentation.Experimental data on the electrocoalescence of very small droplets will be useful to improve the understanding of the dynamics of water-oil interface and to validate numerical models. The simple configuration studied consists in a small droplet pair falling in stagnant model oil, under electric field aligned with the symmetry axis of the droplet pair and the direction of gravity.First part of the work consisted in the well-controlled generation of very small droplet pair (range 20-200 microns) aligned with electric field. Droplet-on-Demand generation by EHD method was improved for a better control of the diameter and electric charge of droplets injected from a single metallic needle. This was obtained by applying to a pendant water meniscus optimized multistage high voltage electric pulses.Electrical and hydrodynamic characterization of the droplet pairs and their coalescence are then mainly deduced from the analysis of falling velocities, with and without applied DC electric field. A complete data set of droplet position and velocity is deduced from video. A special attention was paid to the visualizations of very small droplet and small falling velocities, involving multiple angle of view, strong zooming and high speed video.Modelling the different terms of hydrodynamic and electrostatic interactions between droplets allows deducing from the recorded velocities their respective mass and electric charge. When coalescence occurs, a record of the resulting single droplet velocity, with and without applied voltage, allows controlling the mass and charge conservations and validating the method.A first data set was constituted of about 70 different cases, with varying droplets pair (with a limited diameter range to remain with falling velocities between 0.1 and 0.3 mm/s) and varying applied DC or AC voltage. Analyses of the results and experimental uncertainties, and example of possible comparison with numerical simulations using Comsol Multiphysics™ software, allow performing some recommendations for future work.This work was funded by the project “Fundamental understanding of electrocoalescence in heavy crude oils”; co-ordinated by SINTEF Energy Research. The project was supported by The Research Council of Norway, under the contract no: 206976/E30, and by the following industrial partners: Wärtsilä Oil & Gas Systems AS, Petrobras and Statoil ASA.
253

Interface planta-animal em função da intensidade de aplicação de insumos em pastagem natural / Plant - animal interface in relation to the intensity of input’s application in natural grasslands

Elejalde, Denise Adelaide Gomes January 2011 (has links)
O trabalho foi conduzido na região da Campanha do RS, no município de Quaraí, com objetivo de avaliar a composição florística e bromatológica de pastagem natural submetida ou não à utilização de insumos, e os reflexos sobre o comportamento ingestivo e desempenho animal. Os tratamentos foram pastagem natural (PN), pastagem natural adubada (PNA) e melhorada com adubação + sobressemeadura de espécies hibernais (PNM). O delineamento experimental foi blocos ao acaso, com três repetições, sendo os dados submetidos à análise de variância considerando as estações do ano como medidas repetidas no tempo. Os dados florísticos foram submetidos à análise multivariada. Foram utilizados novilhos da raça Angus em fase de terminação. O estudo da vegetação revelou grande riqueza florística, representada por 264 espécies distribuídas em 161 gêneros e 48 famílias. As famílias mais ricas em contribuição de espécies foram Poaceae, Asteraceae e Cyperaceae com 48, 15 e 13 espécies, respectivamente. Entre as espécies com mais de 1% de valor de importância, 13 eram estivais e dez hibernais, demonstrando um grande equilíbrio entre essas. A maior digestibilidade da forragem dos tratamentos melhorados no inverno e primavera justificou-se pela contribuição em valor de importância nestas épocas, das espécies nativas Andropogon lateralis Nees, Stipa setigera J. Presl, Piptochaetium stipoides (Trin. & Ruprecht.) Hackel var. stipoides, Paspalum notatum Alain, Mnesithea selloana (Hack.) Koning & Sosef, Briza subaristata Lam., Paspalum dilatatum Poir. e da espécie hibernal exótica Lolium multiflorum Lam. A relação entre o tempo de permanência e tempo de pastejo nas áreas de vegetação é de 73,6; 74,7; 34,0 e 51,5%, para Várzea úmida, Várzea seca + Encosta, Sombra e Topo, respectivamente. As variáveis FDNcp, relação NDT:PB, DIVMO e MS da composição química da forragem aparentemente consumida pelos animais explicaram 80% do ganho médio diário. A utilização da adubação ou sua associação com introdução de espécies proporcionam maior contribuição de espécies hibernais no período inverno-primavera em pastagem natural, contribuindo para uma melhor distribuição estacional da produção de forragem. As estações do ano têm marcada influência sobre a composição química da forragem, podendo ser parcialmente estabilizada pelo uso de insumos, notadamente a fertilização, pelo seu efeito na participação de espécies hibernais. Nesse tipo fisionômico de pastagem natural, o repertório de atividades de comportamento ingestivo de novilhos de corte em pastagem natural não é modificado pelos níveis de insumos aplicados. / This work was conducted in Quaraí, Campanha region of Rio Grande do Sul, Brazil, with the aim to evaluate the floristic and chemical composition of natural grassland submitted to the application of inputs, and effects on ingestive behavior and animal production. Treatments were natural grassland (PN), natural grassland fertilized (PNA) and improved natural grassland with fertilization and over seeding of cool season species (PNM). The experimental design was a randomized complete blocks with three replicates. Data were submitted to analyses of variance considering seasons of the year as repeated measurements on time. The floristic data were submitted to multivariate analysis. Aberddeen Angus steers in finishing phase were used. The vegetation study showed high floristic diversity, with 264 plant species distributed in 161 genera and 48 families. The families with higher contribution of species were Poaceae, Asteraceae and Cyperaceae with 48, 15 and 13 plant species, respectively. Considering species with more than 1% of importance value, 13 and ten were warm and cool season plants, respectively, what show a high equilibrium between them. The higher forage digestibility of the improved treatments on winter and spring was justified by the contribution in importance value of natural species as Andropogon lateralis Nees, Stipa setigera J. Presl, Piptochaetium stipoides (Trin. & Ruprecht.) Hackel var. stipoides, Paspalum notatum Alain, Mnesithea selloana (Hack.) Koning & Sosef, Briza subaristata Lam., Paspalum dilatatum Poir. and of the cool season specie Lolium multiflorum Lam. The relation between the permanence time and grazing time on vegetation areas was 73.6; 74.7; 34.0 and 51.5% to wet lowland, dry lowland + downhill, shadow and top, respectively. Variables NDFap, relation TDN:CP, IVOMD and DM of chemical composition of forage apparently intaked by animals explained 80% of average daily gain. The fertilization or its association with the specie‟s over sowing provided bigger contribution of cool season species in natural grasslands, contributing to a better seasonal distribution of forage production. Seasons influences markedly chemical composition of forage, which could be partially stabilized by using inputs, as fertilization, by its effect on the increase of cool season species. In these natural grasslands beef steers‟ activities of ingestive behavior were not modified by the applied input levels.
254

Fluxo de biomassa, produção de forragem e composição quimico-bromatológica do capim-mombaça sob adubação e irrigação / Flow of biomass, production of fodder plant and composition chemistry-bromatológica of capim-mombaça under fertilization and irrigation

Mochel Filho, William de Jesus Ericeira January 2009 (has links)
MOCHEL FILHO, William de Jesus Ericeira. Fluxo de biomassa, produção de forragem e composição quimico-bromatológica do capim-mombaça sob adubação e irrigação. 2009. 83 f. : Dissertação (Mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Zootecnia, Programa de Pós-Graduação em Zootecnia. Fortaleza-CE, 2009. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-08-03T14:08:33Z No. of bitstreams: 1 2009_dis_wjemochelfilho.pdf: 781821 bytes, checksum: 4329b42d80443cde7decfd878f34a6fb (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-03T14:35:37Z (GMT) No. of bitstreams: 1 2009_dis_wjemochelfilho.pdf: 781821 bytes, checksum: 4329b42d80443cde7decfd878f34a6fb (MD5) / Made available in DSpace on 2016-08-03T14:35:37Z (GMT). No. of bitstreams: 1 2009_dis_wjemochelfilho.pdf: 781821 bytes, checksum: 4329b42d80443cde7decfd878f34a6fb (MD5) Previous issue date: 2009 / This work was carried out to evaluate the effects of different irrigation levels and rates of nitrogen on the morphogenetic and structural characteristics, yield production and the composition chemical-bromatologic of mombaçagrass (Panicum maximum cv. Mombaça). The study was conducted in the period from August to December 2007 on Unit Research of EMBRAPA MEIO NORTE, located in city of Parnaíba, Piauí. The treatments consisted of four doses of nitrogen (200, 400, 600 and 800 kg N/ha x year) and two irrigation levels (with a equivalent level to replacement of 50% and 80% of evaporation of the Class A pan - ECA), in a completely randomized block design in a 4 x 2 factorial design with three replications. The plots measuring 3 x 8 m, with 2 x 7 m as floor area for data collection, and made a cut of uniformity (in August) and four cuts to collect data every 30 days (September, October, November, December) 20 cm above the soil. The irrigation level of 80% increases the values of leaf appearance rate (LAR), leaf elongation rate (LER), culm elongation rate (CER) and final leaf length (FLL) when compared with the blade of 50%. Nitrogen fertilization did not influence the LAR, LER, leaf senescence rate (LSR), duration of life of the leaf (DLF) and the FLL. However, with increasing doses of N are the highest values of CER and the lowest dose of N implies a higher value for number of live leaves per tillers (NLT). With the increase of nitrogen rates were increased total dry matter yield (PMST), dry matter yield of green blade (PMSLV), dry matter yield of green culm (PMSCV) and the height of plants and a reduction in nitrogen use efficiency (NUE). The irrigation levels affected only height of grass when the layer of 80% has higher values. Increasing doses of nitrogen reduces the dry matter at the same time as the irrigation level of 80% decreasing these values, both for the leaf and to stem+sheath fraction. With increasing doses of nitrogen there is an increase in levels of neutral detergent insoluble fiber (NDF) and acid detergent insoluble fiber (ADF) only in the leaf and crude protein (CP), both for the leaf and to stem+sheath fraction. The irrigation level of 80% decreases the CP levels, both for the leaf and to stem+sheath fraction at the same time it increases the levels of ADF both for the leaf and to stem+sheath fraction. In the conditions which this work has been done it is recommended to use the blade of 50% of irrigation with nitrogen fertilization between 600 and 800 kg N/ha x year / Objetivou-se avaliar os efeitos de diferentes lâminas de irrigação e doses de nitrogênio sobre as características morfogênicas e estruturais, produção e composição químico-bromatológica do capim-Mombaça. O estudo foi conduzido de agosto a dezembro de 2007, na Unidade de Execução de Pesquisa da EMBRAPA MEIO-NORTE, em Parnaíba, Piauí. Os tratamentos consistiram em quatro doses de nitrogênio (200, 400, 600 e 800 kg de N/ha x ano) e duas lâminas de irrigação (equivalentes à reposição de 50% e 80% da Evaporação do Tanque Classe A – ECA), em um delineamento em blocos casualizados, em esquema fatorial 4 x 2, com três repetições. As parcelas experimentais mediam 3 x 8 m, com 2 x 7 m de área útil, sendo realizados um corte de uniformização (agosto) e quatro cortes para coleta de dados a cada 30 dias (setembro, outubro, novembro, dezembro) 20 cm acima do solo. A lâmina de irrigação de 80% de evaporação do tanque Classe A aumentou os valores de Taxa de Aparecimento de Folhas (TApF), Taxa de Alongamento de Folhas (TAlF), Taxa de Alongamento das Hastes (TAlH) e Comprimento Final da Lâmina Foliar (CFF) em relação à lâmina de 50%. A adubação nitrogenada não influenciou a Taxa de Aparecimento de Folhas (TApF), Taxa de Alongamento de Folhas (TAlF), Taxa de Senescência de Folhas (TSEN), Duração de Vida das Folhas (DVF) e no Comprimento Final da Lâmina Foliar (CFF). Porém, com o aumento das doses de N maiores foram os valores de TAlH e a menor dose de N implicou em maior valor para o NFV. Com o aumento das doses de nitrogênio ocorreu aumento da produtividade de matéria seca total (PMST), produtividade de matéria seca de lâmina verde (PMSLV), produtividade de matéria seca de colmo+bainha verde (PMSCV) e da altura da gramínea bem como uma diminuição da eficiência de uso do nitrogênio (EUN). A lâmina de irrigação influencia apenas na altura das plantas em que a lâmina de 80% proporciona maiores valores. O aumento das doses de nitrogênio diminuiu os teores de matéria seca (MS) ao mesmo tempo em que a lâmina de 80% causou diminuição nesses valores, tanto para lâmina foliar como para colmo+bainha. Com aumento das doses de nitrogênio houve um aumento nos teores de fibra insolúvel em detergente neutro (FDN) e fibra insolúvel em detergente ácido (FDA) apenas da lâmina foliar e de proteína bruta (PB), tanto para a lâmina foliar como para o colmo+bainha. A lâmina de 80% diminuiu os teores de PB tanto para a lâmina foliar como para colmo+bainha ao mesmo tempo em que aumentou os teores de FDA tanto da lâmina foliar como do colmo+bainha. Nas condições em que este trabalho foi realizado recomenda-se a utilização da lâmina de 50% de irrigação com adubações nitrogenadas entre 600 e 800 kg de N/ha x ano
255

Analýza rozvodovosti na území ČR po roce 1989 / Analyses the divorce rate in the Czech Republic after the year 1989

ŠVARZBERGEROVÁ, Barbora January 2014 (has links)
This diploma thesis analyses the divorce rate in the Czech Republic after the year 1989. The first chapter is devoted to the definition of basic terms. Divorce is the legal dissolution of marriage during the life of spouses. Divorce is the dissolving of the bonds of matrimony between a married couple under the rule of law. Divorce is a social phenomenon reflecting the family stability, there is a transformation of traditional behavioural patterns, moral criteria and economic incentives. Since 1989 till present the divorce rate in the Czech Republic is at a high level. The second chapter of the theoretical part evaluates the development and current situation of divorce rate in our country. It is divided into three subsections: Influencing factors of divorce, causes of divorce and divorce rates in Europe. The aim of this diploma thesis is the evaluation of the development of causes of the divorce in the Czech population, capturing the specifics of the development of divorce in the new socio - economic conditions after 1989. With regard to the objective of the diploma thesis I set three hypotheses. Hypothesis 1: Compared with other EU countries in the Czech Republic the divorce rate persists at a high level after 1989. Hypothesis 2: The divorce rate varies by region in the Czech Republic. It is the highest in regions undergoing restructuring of the economy, with high unemployment rate and social problems. Hypothesis 3: The divorce rate is high in big cities and on the contrary low in traditional, predominantly, rural regions with a stable population. I conducted a quantitative research in the form of data analysis. The main source of the data was the Czech Statistical Office and Eurostat. I have analysed and compared the data which reveal the divorce rate in the Czech Republic and the EU in 2011 and the development of divorce from the year 1989. The data were analysed by correlation and spatial analysis and to compare the data I used the Mann-Whitney and Kruskal-Wallis test. Results show that the divorce rate in the Czech Republic in comparison with other EU countries after 1989 remains at a high level. Crude divorce rate since 1989 is around 3.0 divorces per 1000 inhabitants, which represents one of the highest divorce rates among EU countries. The divorce rate in the Czech Republic was one of the few demographic processes that were the least affected by the economic and social transformations after 1989. According to the results of the data analysis for the year 2011 I have verified, that the divorce rate in the Czech Republic is territorially differentiated, varies in different regions, cities and rural areas. High crude divorce rate is in districts undergoing restructuring of the economy and as a result there is a high rate of unemployment and social problems are emerging. The highest divorce rate in 2011 was in Česká Lípa. Conversely, the lowest crude divorce rate is the less populated districts, with a stable population and a high proportion of religious people. In 2011, the lowest crude divorce rate was in the district of Jihlava. Religion had the most statistically significant effect on the divorce rate. In districts with a higher proportion of religious people the crude divorce rate is lower than in districts with a lower proportion of religious people.
256

Estudos eletroquímicos fundamentais para a detecção de fenol em interfaces do tipo petróleo/água

Silva, Roberval Alves da January 2015 (has links)
Orientador: Prof. Dr. Hugo Barbosa Suffredini / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2015. / O presente trabalho é referente à utilização de técnicas eletroanalíticas diretamente na interface formada entre dois líquidos imiscíveis. Esta nova metodologia de trabalho está em pleno desenvolvimento em nosso grupo de pesquisa, apresentando resultados promissores em diversas vertentes. De maneira específica neste projeto, os estudos foram realizados em fase aquosa, constituída ora por uma solução de NaCl 1x10-3 mol L-1, ora por água do mar, bem como em fase oleosa, aqui representada pelo petróleo bruto. Utilizou-se o eletrodo impresso de carbono como ferramenta de trabalho, aplicando-se técnicas eletroanalíticas, tais como a voltametria cíclica e a voltametria de onda quadrada. Contaminou-se artificialmente o petróleo com algumas moléculas-modelo, em particular o fenol e o cicloexano. Para iniciar os experimentos, verificou-se a possibilidade de obtenção das respostas de oxidação ou redução das moléculas a partir da técnica de voltametria cíclica, utilizando nesta etapa o NaCl 1x10-3 mol L-1 como eletrólito suporte. Em seguida, estudaram-se os mesmos sistemas por voltametria de onda quadrada, técnica esta mais sensível e adequada para fins analíticos. Resultados obtidos mostraram ser possível realizar a caracterização de moléculas introduzidas artificialmente à fase petróleo. Foram satisfatórios nos experimentos realizados neste trabalho a obtenção de dados que permitiram se obter voltamogramas para melhor análise e compreensão dos fenômenos de oxidação e redução das moléculas estudadas. Para tanto, foi utilizando como ferramenta principal as técnicas eletroanalíticas. Ainda, houve a possibilidade de se determinar o tempo de saturação do eletrodo impresso de carbono, na área interfacial petróleo/água. Deste trabalho qualitativo, foi possível concluir que todas as moléculas propostas neste projeto foram detectadas com êxito, ou seja, a técnica proposta em interfaces foi eficiente para a finalidade proposta. Trabalhos futuros serão necessários para refinar a metodologia e aplicar o sistema em amostras reais. / This work describes the use of a new electrochemical technique applied directly at the interface between two immiscible liquids. This new methodology is now been developed in our group and promising results were found in different research lines. More specifically, the studies in this project were carried out in aqueous support electrolyte solution constituted by a home-made 1 x 10-3 NaCl solution and also constituted by natural sea salt water. The organic phase was constituted by crude oil. A carbon screen-printed electrode was used as the main tool in this work. Cyclic Voltammetry (CV) and Square Wave Voltammetry (SWV) were used as electrochemical techniques. Portions of crude oil were contaminated with model molecules, as phenol and cyclohexane. Firstly, the CV was used to determine the possibility of detection. Following these preliminary studies, SWV studies were carried out since that technique is more adequate to promote analytical studies. Results indicates that was possible to characterize molecules artificially introduced to oil phase. Furthermore, it was possible to determine the time of saturation of the printed-screen carbon electrode at the interfacial Oil / water region. It was possible to conclude from this qualitative work that all molecules were successfully detected directly at the crude oil/water interface. On the other hand, future works will be necessary to improve this kind of methodology.
257

COMPOSIÇÃO CORPORAL DE MATRIZES DE CORTE SUBMETIDAS A DIFERENTES HORÁRIOS DE ARRAÇOAMENTO / CORPORAL COMPOSITION OF BROILER BREEDERS FED WITH DIFFERENT FEEDING SCHEDULES

Toledo, Taiani dos Santos de 24 February 2015 (has links)
The different feeding schedules used in the poultry industry contribute to improve the nutrients distribution in the animal, as well as egg production. The study was carried out to analize the corporal composition of broiler breeders fed in different feeding schedules and their effect in body weight and body weight gain, as well as egg production. The broiler breeders were fed in three feeding schedules. The feeding schedules evaluated were: 1- a single feeding at 08:00 am, 2- twice daily feeding (50% at 08:00 am and 50% at 3:00 pm), 3- a single feeding at 3:00 pm. The hens were allocated in a completely randomized design of 3 treatments with 5 replications of 22 females and 3 males per repetition, to evaluate the corporal composition parameters were slaughtered two hens per repetition. Body weight, body weight gain, egg production, dry matter, mineral matter, crude protein, ether extract, calcium and phosphorus levels were evaluated. The feeding schedule late had higher body weight (P=0.0273) and body weight gain (P=0.0981) than early feeding schedule used. The first feeding schedule showed better egg production (P=0.0300) than the third feeding schedule. The percentage of ash (P=0.0741) and phosphorus (P=0.0875) were higher in broilers breeders fed at 8 am than hens fed at 3 pm, not different from the treatment 2. The calcium content were not affected by feeding scheduler used. The broiler breeder feeding at 8:00 am had more level of dry matter, crude protein and lower ether extract than feeding schedule late. Broiler breeder fed with feeding schedule late had lower egg production and higher body weight gain than others, consequently the most body fat deposition. / A utilização de horários de arraçoamento distintos ao empregado pela indústria visa contribuir para a melhoria na distribuição dos nutrientes requeridos para mantença, assim como para a produção das aves. O presente experimento foi conduzido com o intuito de analisar a composição corpórea de reprodutoras de corte avícolas submetidas a diferentes horários de arraçoamento e o seu impacto mediante o peso e ganho corporal, bem como, a produção de ovos. Os animais foram submetidas a 3 tratamentos: 1- horário de arraçoamento único às 08h00min, 2- horário de arraçoamento dual (50% de manhã 08h00min e 50% à tarde 15h00min), 3- horário de arraçoamento único às 15h00min. Foi utilizado um delineamento inteiramente casualizado com três tratamentos e cinco repetições de vinte e duas aves, sendo que para parâmetros referentes à composição corporal foram utilizadas duas aves abatidas para cada repetição. Foram avaliados: Peso e ganho corporal, taxa de postura, matéria seca, matéria mineral, proteína bruta, extrato etéreo, cálcio e fósforo. O horário de arraçoamento tardio apresentou aves mais pesadas (P=0,0273), com consequente ganho de peso mais elevado (P=0,0981) do que o horário matinal. O tratamento 1 apresentou a maior produção total de ovos (P=0,0300) em relação ao horário 3 A porcentagem de cinzas (P=0,0741) e fósforo (P=0,0875) foi maior em matrizes de corte alimentadas às 08h00min do que aves alimentadas às 15h00min, não diferindo do tratamento 2. Aves arraçoadas no período da manhã apresentaram maior teor de matéria seca e umidade, refletindo em um maior percentual de proteína bruta e consequentemente em um menor porcentual de extrato etéreo do que o horário de arraçoamento tardio. Reprodutoras avícolas alimentadas em horários tardios apresentaram uma menor produção de ovos com maior ganho de peso e consequentemente, maior deposição de gordura corporal.
258

Alimentos volumosos na produção de leite de cabra

Ribeiro, Marcela Silva [UNESP] 06 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-06Bitstream added on 2014-06-13T20:36:08Z : No. of bitstreams: 1 ribeiro_ms_me_botfmvz.pdf: 174069 bytes, checksum: 2dd52fa6a3e9b9232005ba7edbfded45 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / The objective of this paper was to compare dried corn plant (DCP) as a roughage (R) source for lactating goats to roughages traditionally used for feeding ruminants: alfalfa hay (AH) and coastcross hay (CCH). Twenty-one crossbred goats weighing an average of 66.48 kg were used. After reaching their lactation peak, they were distributed among seven 3 x 3 latin squares. Each experimental diet consisted of one of the roughages fed ad lib plus a commercial concentrate (C) for lactating goats, fed on a basis of 1 kg for every 2.5 kg of milk. Each group, composed by seven animals kept in a collective pen with slatted floor, stayed in each treatment for two weeks; the first week was an adaptation period, whereas milk yield measurements and milk samples were collected during the second week. Dry or as-fed matter intake was higher in AH than in DCP or CCH. No treatment effect on C intake was detected. The higher dry matter intake in AH led to higher intakes of crude protein, ether extract, minerals, nitrogen-free extract, total digestible nutrients and acid detergent fiber, both in R and in the total diet (R + C). No treatment effect was observed for either crude fiber or neutral detergent fiber intakes in R and in R+C. Milk yield and milk PB content were higher in AH than in DCP or CCH; however, milk yield corrected for 3.5% fat and body weight loss were higher in AH than in CCH, but DCP did not differ from the other two treatments. Production cost per kg of milk was lower for DCP than for AH or CCH. The results show that DCP is a valid alternative roughage for dairy goats.
259

Silagem de capim papuã (urochloa plantaginea) x silagem de sorgo (sorghum bicolor (l.) moench) na terminação de novilhos em confinamento / Alexander grass silage (urochloa plantaginea) x sorghum silage (sorghum bicolor (l.) moench) in feedlot finishing steers

Argenta, Flânia Mônego 27 February 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work had as objective evaluate the use of Alexander grass silage as an alternative for substitution of sorghum silage in feedlot finishing steers. Twelve animals, with average weight and age initial of 245 kg and 20 months, respectively, pertaining to Nellore (N), Charolais (C), 21/32 N 11/32 C, 21/32 C 11/32 N, 43/64 N 21/64C e 43/64 C 21/64N genetic groups, were used. The diet was composed by roughage:concentrate relation of 50:50 (on dry matter basis), containing different sources of roughage: Alexander grass silage or sorghum silage, besides of concentrated compound by wheat bran, soybean meal, corn grain, limestone, sodium chloride and urea. The intakes of dry matter (DM), crude protein, ether extract, neutral detergent fiber and acid detergent fiber didn t differ between roughage sources, presenting average values of 10.18; 1.28; .20; 4.96 and 2.51 kg/day, respectively. However, ether extract intake per metabolic size and percentage of body weight were greater for animals that consumed sorghum silage, showing values of 2.74 and 2.36 g/metabolic size and .06 and .05 kg/100 kg of live weight. Similar behavior was observed for digestible energy intake, presenting values of 346.87 and 302.83 g/metabolic size and 8.10 and 7.02 kg/100 kg of live weight. Average daily weight gain, body condition and food conversion weren t influenced by roughage source, showing average values of 1.31 kg; 4.05 points and 7.78 kg of DM/weight gain, respectively. The use of different sources of roughage didn t affect the time spent with feeding, rumination and idle, presenting averages of 4.29; 11.52 and 8.06 h, respectively. The number of meals and time of daily meals (minutes) also weren t affect by treatments, showing values of 7.72 and 35.79. the number of chewed by ruminal bolus, time of chew per bolus, number of bolus, number of daily chew and total chewing time expressed in h/day didn t differ (P>.05) between treatments, presenting average values of 59; 53; 550.44; 32,059.5 and 12.36, respectively. The use of Alexander grass is a viable alternative to substitute sorghum silage without any variation on ingestive behavior and animal response. / Este trabalho teve por objetivo avaliar o uso da silagem de capim papuã como alternativa de substituição a silagem de sorgo, na terminação de bovinos em confinamento. Foram utilizados 12 animais com peso e idade média inicial de 245 kg e 20 meses, respectivamente, pertencentes aos grupos genéticos Nelore (N), Charolês (C), 21/32 N 11/32 C, 21/32 C 11/32 N, 43/64 N 21/64C e 43/64 C 21/64N. A dieta foi composta por relação volumoso:concentrado de 50:50 (base na matéria seca), contendo diferentes fontes de volumoso: Silagem de capim papuã ou silagem de sorgo , além do concentrado composto por farelo de trigo, farelo de soja, milho em grão, calcário calcítico, cloreto de sódio e uréia. O consumo diário de matéria seca; proteína bruta; extrato etéreo; fibra em detergente neutro e fibra em detergente ácido não diferiram entre as fontes de volumosos, sendo os valores médios de 10,18; 1,28; 0,20; 4,96 e 2,51 kg/dia, respectivamente. No entanto, o consumo de extrato etéreo por tamanho metabólico e por percentual de peso corporal foram maiores para os que consumiram silagem de sorgo, obtendo valores de 2,74 e 2,36 g/tamanho metabólico e 0,06 e 0,05 kg/100 kg de peso vivo. Mesmo comportamento foi observado para o consumo de energia digestível, apresentando valores de 346,87 e 302,83 g/tamanho metabólico e 8,10 e 7,02 kg/100 kg de peso vivo. O ganho médio diário, escore corporal final e a conversão alimentar não foram influenciados pelo tipo de volumoso, sendo os valores médios de 1,31 kg; 4,05 pontos e 7,78 kg de MS/kg de ganho de peso, respectivamente. O uso dos diferentes tipos de volumoso, não interferiu no tempo de alimentação, ruminação e ócio com médias de 4,29; 11,52 e 8,06 h, respectivamente. As variáveis número de refeições e tempo de refeições diárias (minutos), também não foram influenciadas pelos tratamentos, sendo respectivamente 7,72 e 35,79. O número de mastigadas por bolo ruminal, tempo de mastigada por bolo (segundos), número de bolos, número de mastigadas diárias e tempo de mastigação total expressos em h/dia, não diferiram (P>0,05) entre os tratamentos, apresentando respectivamente valores médios de 59; 53; 550,44; 32.059,5 e 12,36. O uso da silagem de capim papuã é uma alternativa viável para substituir a silagem de sorgo, não alterando o comportamento ingestivo e a resposta animal. Alimentação. Tempo de ruminação. Ócio. Ganho médio diário.
260

Avalia??o da atividade antimal?rica de extratos obtidos de algas marinhas no litoral do Rio Grande do Norte

Dantas, Gracielle Rodrigues 07 March 2012 (has links)
Made available in DSpace on 2014-12-17T14:10:25Z (GMT). No. of bitstreams: 1 GracielleRD_DISSERT.pdf: 641978 bytes, checksum: 570ea10863ca885dc9cff38e172d53f2 (MD5) Previous issue date: 2012-03-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Malaria is a major parasitic disease worldwide, accounting for about 500 million cases and causing 2 million to 3 million deaths annually. Four species are responsible for transmitting this disease to humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium ovale. The parasite resistance to antimalarial drugs and the usual limitations of the vector control implications are contributing to the spread of the disease. The most of significant advances in the search for new antimalarial drugs is based on natural components, the main ones being currently used antimalarial drugs derived from plants. Research on natural products of marine origin (particularly algae) show that some species possess antiplasmodial activity. Knowing that the coast of Rio Grande do Norte is home to several species of algae, the present study was to evaluate, for the first time, the antimalarial activity of ethanolic extracts of seaweed Spatoglossum schroederi, Gracilaria birdiae and Udotea flabellum against Plasmodium falciparum 3D7 strain tests and in vitro using the murine model (Plasmodium berghei) for evaluation in vivo. These species were ground, macerated with ethanol for 24 hours and the extracts concentrated in rotaevaporador (45 ? C ? 5 ? C). For in vitro tests, the extracts were diluted and tested at concentrations between 100 and 1.56 μg/ml (seven concentrations in triplicate), in order to obtain IC50 of each extract. The cytotoxicity tests with macrophages and BGM were performed using the MTT colorimetric assay. BGM macrophages and cells were distributed in 96 wells per plate (1x 105 to macrophages and 1x104 cells per well for BGM) and incubated for 24h at 37 ? C. The ethanol extracts were diluted and tested at concentrations of 100 to 1,56 μg/ml (seven concentrations in triplicate). After periods of 24 hours of incubation with the extracts, 100 μg of MTT was added to each well, and 3 hours elapsed, the supernatant was removed and added 200 μl of DMSO in each well. The absorbance of each well was obtained by reading on a spectrophotometer at 570 nm filter. To evaluate the acute toxicity in vivo, Swiss mice received a single dose (oral) 2000 mg/kg/animal of each extract tested. The parameters of acute toxicity were observed for 8 days. For in vivo tests, Swiss mice were inoculated with 1x105 erythrocytes infected with P. berghei. The treatment was given first to fourth day after infection with 0.2 ml of the extracts in doses of 1000 and 500 mg//g animal. The negative control group received 0.2 ml of 2% Tween-20, whereas the positive control group received sub-dose of chloroquine (5 mg/kg/animal). The assessment of antimalarial activity was done by suppressing suppressing the parasitemia at 5 and 7 days after infection. The growth inhibition of parasites was determined relative to negative control (% inhibition = parasitaemia in control - parasitemia in sample / parasitemia control x 100), the mortality of animals was monitored daily for 30 days The results showed that algae Spatoglossum schroederi and Udotea flabellum showed antimalarial activity in vitro, with reduced parasitemia of 70.54% and 54, respectively. The extracts of the three algae tested showed moderate to high cytotoxicity. Algae S. schroederi and U. flabellum were active against P. berghei only at doses of 500 mg / kg with reduction ranging from 54.58 to 52.65% for the fifth day and from 32.24 to 47.34% for the seventh day, respectively. No toxicity was observed in vivo at the dose tested, over the 8 days of observation. Although preliminary data, the bioactive components in those possible seaweed may be promising for the development of new anti-malarial drugs / A mal?ria ? a maior doen?a paras?tica mundial, respons?vel por cerca de 500 milh?es de casos e causando 2 a 3 milh?es de mortes anualmente. Quatro esp?cies s?o respons?veis pela transmiss?o dessa doen?a ao homem: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae e Plasmodium ovale. A resist?ncia do parasito aos antimal?ricos usuais e as limita??es existentes no combate ao vetor s?o implica??es que contribuem para a expans?o dessa parasitose. Os avan?os mais significativos na busca de novos medicamentos contra a mal?ria baseiam-se em componentes naturais, sendo os principais antimal?ricos atualmente utilizados derivados de plantas. Pesquisas com produtos naturais de origem marinha (particularmente as algas) mostram que algumas esp?cies possuem atividade antiplasm?dica. Sabendo que o litoral do Rio Grande do Norte abriga v?rias esp?cies de algas, o presente estudo consistiu em avaliar, pela primeira vez, a atividade antimal?rica dos extratos etan?licos das algas Spatoglossum schroederi, Gracilaria birdiae e Udotea flabellum contra a cepa 3D7 Plasmodium falciparum em testes in vitro e utilizando o modelo murino (P. berghei) para avalia??o in vivo. As algas foram trituradas, maceradas com etanol por 24 horas e os extratos concentrados em rotaevaporador (45? C ? 5?C). Para os testes in vitro, os extratos foram dilu?dos e testados nas concentra??es entre 100 e 1,56 μg/ml (sete concentra??es em triplicata), com a finalidade de obten??o da CI50 de cada extrato. Os testes de citotoxicidade com macr?fagos e c?lulas BGM foram realizados usando o ensaio colorim?trico MTT. Macr?fagos e c?lulas BGM foram distribu?das em 96 po?os por placa (1x 105 para macr?fagos e 1x104 c?lulas por po?o para BGM), sendo incubadas por 24h a 37?C. Os extratos etan?licos foram dilu?dos e testados nas concentra??es de 100 at? 1,56 μg/ml (sete concentra??es em triplicata). Ap?s per?odos de 24h de incuba??o com os extratos, 100 μl de MTT foi adicionado a cada po?o, e decorridas 3h, o sobrenadante foi removido e adicionou-se 200 μl DMSO em cada po?o. A absorb?ncia de cada po?o foi obtida atrav?s de leitura em espectrofot?metro com filtro de 570 nm. Para avaliar a toxicidade aguda in vivo, camundongos Swiss receberam dose ?nica (oral) de 2000 mg/kg/animal dos extratos testados. Os par?metros de toxicidade aguda foram observados durante 8 dias. Para os testes in vivo, camundongos Swiss foram inoculados com 1x105 hem?cias infectadas com Plasmodium berghei. O tratamento deu-se do primeiro ao quarto dia ap?s a infec??o, com 0,2 ml dos extratos em doses de 1000 e 500 mg/kg/animal. O grupo controle negativo recebeu 0,2 ml de Tween-20 2%, enquanto que o grupo controle positivo recebeu sub-dose de cloroquina (5 mg/kg/animal). A avalia??o da atividade antimal?rica foi feita atrav?s da supress?o da parasitemia no 5? e 7? dias ap?s infec??o. A inibi??o do crescimento dos parasitos foi determinada em rela??o ao grupo controle negativo (% inibi??o = parasitemia do controle parasitemia com amostra/ parasitemia do controle x 100); a mortalidade dos animais foi acompanhada diariamente por 30 dias. Os resultados mostraram que as algas Spatoglossum schroederi e Udotea flabellum apresentaram atividade antimal?rica in vitro, com redu??o da parasitemia de 70,54 e 54%, respectivamente. Os extratos das tr?s algas testadas mostraram citotoxicidade moderada a elevada. As algas S. schroederi e U. flabellum foram ativas contra o P. berghei apenas nas doses de 500 mg/kg com redu??o variando de 54,58 a 52,65% para o quinto dia e 32,24 a 47,34% para o s?timo dia, respectivamente. N?o foi observada toxicidade in vivo para a dose testada, durante os 8 dias de observa??o. Embora sejam dados preliminares, os poss?veis componentes bioativos presentes nessas algas marinhas podem ser promissores para o desenvolvimento de novas drogas antimal?ricas

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