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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.
371

Um algoritmo inspirado em colônias de abelhas para otimização numérica com restrições

Duarte, Grasiele Regina 06 March 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-03-06T11:57:32Z No. of bitstreams: 1 grasielereginaduarte.pdf: 2553018 bytes, checksum: e0b9afbcc0b18965321f8db8ea7d38b8 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-03-06T20:19:40Z (GMT) No. of bitstreams: 1 grasielereginaduarte.pdf: 2553018 bytes, checksum: e0b9afbcc0b18965321f8db8ea7d38b8 (MD5) / Made available in DSpace on 2017-03-06T20:19:40Z (GMT). No. of bitstreams: 1 grasielereginaduarte.pdf: 2553018 bytes, checksum: e0b9afbcc0b18965321f8db8ea7d38b8 (MD5) Previous issue date: 2015-03-06 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os problemas de otimização estão presentes em diversas áreas de atuação da sociedade e o uso de algoritmos bio-inspirados para a resolução de problemas complexos deste tipo vem crescendo constantemente. O Algoritmo Colônia de Abelhas Artificiais (ABC – do inglês Artificial Bee Colony) é um algoritmo bio-inspirado proposto em 2005 para a resolução de problemas de otimização multimodais e multidimensionais. O fenômeno natural que inspirou o desenvolvimento do ABC foi o comportamento inteligente observado em colônias de abelhas, mais especificamente no forrageamento. O ABC foi proposto inicialmente para ser aplicado na resolução de problemas sem restrições. Este trabalho avalia o desempenho do ABC quando aplicado na resolução de problemas de otimização com restrições. Para o tratamento das restrições, métodos de penalização serão incorporados ao ABC. São analisados diversos métodos de penalização, de diferentes tipos, com o objetivo de identificar com qual deles o algoritmo apresenta melhor desempenho. Além disto, são avaliadas possíveis limitações e cuidados que devem ser tomados ao combinar métodos de penalização ao ABC. O algoritmo proposto é avaliado através da resolução de problemas de otimização encontrados na literatura. Vários experimentos computacionais são realizados e gráficos e tabelas são gerados para demonstração dos resultados obtidos que também são discutidos. / Optimization problems are present in several areas of society and the use of bio-inspired algorithms to solve complex problems of this type has been growing constantly. The Artificial Bee Colony Algorithm (ABC) is a bio-inspired algorithm proposed in 2005 for solving multimodal and multidimensional optimization problems. The natural phenomenon that inspired the development of the ABC was intelligent behavior observed in bee colonies, more specifically in foraging. The ABC was initially proposed to be applied to solve unconstrained problems. This study evaluates the performance of ABC when applied in solving constrained optimization problems. For the treatment of constraints, penalty methods will be incorporated into the ABC. Several penalty methods, of different types, are analyzed with the goal of identifying which of these penalty methods offers better performance. Furthermore, possible limitations and care that should be taken when combining penalty methods to ABC are evaluated. The proposed algorithm is evaluated by solving optimization problems found in the literature. Several computational experiments are performed and graphs and tables are generated for demonstration of the obtained results which are also discussed.
372

PRODUTOS APÍCOLAS COMO ANTIOXIDANTES EM PEIXES FRENTE A DESAFIOS OXIDANTES PROVOCADOS POR TEBUCONAZOLE. / BEE PRODUCTS AS ANTIOXIDANTS IN FISH FACE TO OXIDIZING CHALLENGES CAUSED BY TEBUCONAZOL.

Ferreira, Daiane 25 October 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper present alternatives to mitigate the deleterious effects caused by pesticides from crops that contaminate ponds and water bodies, located very close to the growing areas. This proximity causes oxidative damage in fish. The suggested alternative is the use of bee products, which generate lower amounts of waste in the environment and has low cost. Since this organization has been growing crops only. We tested three different concentrations of honey (0,025g L-1; 0,075g L-1; 0,125g L-1), bee pollen (0,01g L-1; 0,03g L-1; 0,05g L-1), royal jelly (0,005g L-1; 0,015g L-1; 0,025g L-1) and propolis (0,01g L-1; 0,05g L-1; 0,1g L-1) and associated or not with fungicide tebuconazol (0,088mg L-1), apiculture products showed protective effect on fish, mainly inhibit / reverse lipid peroxidation, protein carbonylation and increase the activity of catalase, superoxide dismutase and glutathione S-transferase, contributing to the redox state of the cell. Our data suggest the antioxidant potential of honey, bee pollen, propolis and royal jelly added to water as protective substances against oxidative stress caused by agrochemicals, especially tebuconazole. / Este trabalho apresenta novas alternativas para mitigar efeitos deletérios causados por agroquímicos provenientes de lavouras, que contaminam açudes e corpos de água, localizados muito próximos às áreas de cultivo. Esta proximidade e contaminação causa danos oxidativos em peixes. A alternativa sugerida é o uso de produtos apícolas, que geram resíduos de baixo impacto para o meio ambiente. Uma vez que esta associação de culturas só vem crescendo. Foram testadas três concentrações diferentes de mel (0,025g L-1; 0,075g L-1; 0,125g L-1), pólen apícola (0,01g L-1; 0,03g L-1; 0,05g L-1), geleia real (0,005g L-1; 0,015g L-1; 0,025g L-1) e própolis (0,01g L-1; 0,05g L-1; 0,1g L-1) associadas e ou não ao fungicida tebuconazole (0,088mg L-1) Os produtos apícolas apresentaram efeito protetor aos peixes, principalmente por inibir/reverter a peroxidação lipídica, carbonilação proteica e aumentar a atividade das enzimas catalase, superóxido dismutase e glutationa-S-transferase, contribuindo para o estado redox da célula. Os dados apresentados sugerem o potencial do mel, pólen apícola, própolis e geleia real adicionados a água como substâncias protetoras contra o estresse oxidativo causado por agroquímicos, em especial o tebuconazole.
373

Angle modulated population based algorithms to solve binary problems

Pampara, Gary 24 February 2012 (has links)
Recently, continuous-valued optimization problems have received a great amount of focus, resulting in optimization algorithms which are very efficient within the continuous-valued space. Many optimization problems are, however, defined within the binary-valued problem space. These continuous-valued optimization algorithms can not operate directly on a binary-valued problem representation, without algorithm adaptations because the mathematics used within these algorithms generally fails within a binary problem space. Unfortunately, such adaptations may alter the behavior of the algorithm, potentially degrading the performance of the original continuous-valued optimization algorithm. Additionally, binary representations present complications with respect to increasing problem dimensionality, interdependencies between dimensions, and a loss of precision. This research investigates the possibility of applying continuous-valued optimization algorithms to solve binary-valued problems, without requiring algorithm adaptation. This is achieved through the application of a mapping technique, known as angle modulation. Angle modulation effectively addresses most of the problems associated with the use of a binary representation by abstracting a binary problem into a four-dimensional continuous-valued space, from which a binary solution is then obtained. The abstraction is obtained as a bit-generating function produced by a continuous-valued algorithm. A binary solution is then obtained by sampling the bit-generating function. This thesis proposes a number of population-based angle-modulated continuous-valued algorithms to solve binary-valued problems. These algorithms are then compared to binary algorithm counterparts, using a suite of benchmark functions. Empirical analysis will show that the angle-modulated continuous-valued algorithms are viable alternatives to binary optimization algorithms. Copyright 2012, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Pamparà, G 2012, Angle modulated population based algorithms to solve binary problems, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-02242012-090312 / > C12/4/188/gm / Dissertation (MSc)--University of Pretoria, 2012. / Computer Science / unrestricted
374

Amélioration des métaheuristiques d'optimisation à l'aide de l'analyse de sensibilité / Improvement of optimization metaheuristics with sensitivity analysis

Loubiere, Peio 21 November 2016 (has links)
L'optimisation difficile représente une classe de problèmes dont la résolution ne peut être obtenue par une méthode exacte en un temps polynomial.Trouver une solution en un temps raisonnable oblige à trouver un compromis quant à son exactitude.Les métaheuristiques sont une classe d'algorithmes permettant de résoudre de tels problèmes, de manière générique et efficiente (i.e. trouver une solution satisfaisante selon des critères définis: temps, erreur, etc.).Le premier chapitre de cette thèse est notamment consacré à la description de cette problématique et à l'étude détaillée de deux familles de métaheuristiques à population, les algorithmes évolutionnaires et les algorithmes d'intelligence en essaim.Afin de proposer une approche innovante dans le domaine des métaheuristiques, ce premier chapitre présente également la notion d'analyse de sensibilité.L'analyse de sensibilité permet d'évaluer l'influence des paramètres d'une fonction sur son résultat.Son étude caractérise globalement le comportement de la fonction à optimiser (linéarité, influence, corrélation, etc.) sur son espace de recherche.L'incorporation d'une méthode d'analyse de sensibilité au sein d'une métaheuristique permet d'orienter sa recherche le long des dimensions les plus prometteuses.Deux algorithmes réunissant ces notions sont proposés aux deuxième et troisième chapitres.Pour le premier algorithme, ABC-Morris, la méthode de Morris est introduite dans la métaheuristique de colonie d'abeilles artificielles (ABC).Cette inclusion est dédiée, les méthodes reposant sur deux équations similaires.Afin de généraliser l'approche, une nouvelle méthode, NN-LCC, est ensuite développée et son intégration générique est illustrée sur deux métaheuristiques, ABC avec taux de modification et évolution différentielle.L'efficacité des approches proposées est testée sur le jeu de données de la conférence CEC 2013. L'étude se réalise en deux parties: une analyse classique de la méthode vis-à-vis de plusieurs algorithmes de la littérature, puis vis-à-vis de l'algorithme d'origine en désactivant un ensemble de dimensions, provoquant une forte disparité des influences / Hard optimization stands for a class of problems which solutions cannot be found by an exact method, with a polynomial complexity.Finding the solution in an acceptable time requires compromises about its accuracy.Metaheuristics are high-level algorithms that solve these kind of problems. They are generic and efficient (i.e. they find an acceptable solution according to defined criteria such as time, error, etc.).The first chapter of this thesis is partially dedicated to the state-of-the-art of these issues, especially the study of two families of population based metaheuristics: evolutionnary algorithms and swarm intelligence based algorithms.In order to propose an innovative approach in metaheuristics research field, sensitivity analysis is presented in a second part of this chapter.Sensitivity analysis aims at evaluating arameters influence on a function response. Its study characterises globally a objective function behavior (linearity, non linearity, influence, etc.), over its search space.Including a sensitivity analysis method in a metaheuristic enhances its seach capabilities along most promising dimensions.Two algorithms, binding these two concepts, are proposed in second and third parts.In the first one, ABC-Morris, Morris method is included in artificial bee colony algorithm.This encapsulation is dedicated because of the similarity of their bare bone equations, With the aim of generalizing the approach, a new method is developped and its generic integration is illustrated on two metaheuristics.The efficiency of the two methods is tested on the CEC 2013 conference benchmark. The study contains two steps: an usual performance analysis of the method, on this benchmark, regarding several state-of-the-art algorithms and the comparison with its original version when influences are uneven deactivating a subset of dimensions
375

Diversité génétique et phylogéographie de l'abeille Apis mellifera dans les îles du sud-ouest de l'océan Indien / Genetic diversity and phylogeography of the Apis bee will mellifera in the islands of the South-west of the Indian Ocean

Techer, Maéva Angélique 20 November 2015 (has links)
Les îles du Sud-Ouest de l'océan Indien (SOOI) abritent une faune et une flore exceptionnelle et constituent l'un des cinq hotspot de biodiversité les plus importants au monde. L'abeille domestique Apis mellifera occupe divers habitats dans la majorité de ces îles et interagit avec une flore indigène et endémique. Elle est également exploitée par l'Homme pour l'apiculture. A. mellifera a divergé en plusieurs lignées évolutives et sous-espèces dans son aire d'origine. Parmi-elles, A. m. unicolor a été décrite comme endémique de Madagascar et appartient à la lignée africaine A. Les objectifs de cette thèse étaient de caractériser l'abeille dans les archipels des Mascareignes, Comores et Seychelles en identifiant les lignées évolutives et sous-espèces présentes avec des marqueurs mitochondriaux (région intergénique COI-COII, gène ND2). Dans un second temps, une étude de la diversité et de la structure génétique a été réalisée sur ces mêmes populations insulaires (15 microsatellites). Un total de 4095 colonies ont été échantillonnées dans le SOOI et 238 dans l'aire naturelle continentale. Trois des quatre lignées évolutives (A, C et M) ont été détectées dans les 10 îles étudiées et ce en différentes proportions. La lignée africaine A et A. m. unicolor sont prépondérantes dans le SOOI excepté à Rodrigues (100% lignée européenne C). Dans toutes les îles de l'archipel des Comores et des Seychelles, 100% des colonies échantillonnées appartiennent à la lignée A, 95,2% à La Réunion et seulement 54,2% à Maurice. Les îles de l'archipel des Comores constitueraient une zone de contact entre la lignée africaine continentale et les populations d'A. m. unicolor. La diversité génétique nucléaire est forte dans les archipels du SOOI et est structurée par îles et archipels. En outre, les populations du SOOI se différencient fortement des populations continentales africaines et européennes. La combinaison des différents marqueurs privilégie l'hypothèse d'une colonisation ancienne et naturelle d'A. m. unicolor depuis Madagascar à La Réunion, Maurice et aux Seychelles. / The South West Indian Ocean (SWIO) islands are home to an exceptional flora and fauna and are considered as one the five most important biodiversity hotspots in the world. In most islands of this region, the honeybee Apis mellifera occupies diverse habitats. Regarding its ability as a generalist pollinator, honeybee interacts with native and highly endemic flora. Furthermore, this species is used by human for beekeeping as it is able to produce honey, pollen and other hive products. Within the large group of bees (Apidae), A. mellifera is a model of diversity that has diverged into several lineages and subspecies in its native range. Among the 28 recognized subspecies, A. m. unicolor has been described as endemic to Madagascar and belongs to the African A lineage. The Mascarenes, Comoros and Seychelles archipelagos surround this continental island but the A. mellifera populations present have been little or never studied. The aims of this thesis were to characterize the honeybee from the Mascarenes (La Réunion, Mauritius, Rodrigues), Comoros (Anjouan, Mohéli, Grande Comore, Mayotte) and Seychelles (Mahé, Praslin, La Digue) archipelagos by determining the evolutionary lineages and subspecies present. Secondly, a study of genetic diversity and structure were conducted on these same insular populations. For that, a large sampling was carried (n = 4095 colonies from the SWIO, and 238 from native continental areas) and was combined to molecular analyzes using mitochondrial markers (sequencing of the COI-COII intergenic region and ND2 gene) and nuclear markers (15 microsatellite loci). Three of the four evolutionary lineages (A, C and M) were detected in different proportions in the 10 studied islands. The African A lineage and A. m. unicolor subspecies were predominant in the SWIO excepted for Rodrigues exclusively from the European C lineage. All sampled colonies from the Seychelles and Comoros archipelagos belong to the African lineage while in La Réunion the proportion reach 95.2% and only 54.2% in Mauritius. The presence of the Z African sub-lineage has been described for the first time out of Africa in two Seychelles islands. Moreover, Comoros islands may constitute a contact area between the continental African lineage and A. m. unicolor populations (insular African lineage). The SWIO populations show high levels of nuclear genetic diversity and a structuration by island and archipelago. In addition, SWIO populations strongly differentiated from African and European continental populations. The combined results from different molecular markers favor the hypothesis of an ancient and natural colonization from Madagascar to La Réunion, Mauritius and Seychelles islands. Therefore, the previous referenced interactions between the honeybee and the endemic fauna and flora in the SWIO might be explained by a long cohabitation in addition to its generalist pollinator ability.
376

Ressources pollinifères et mellifères de l'Abeille domestique, Apis Mellifera, en paysage rural du nord-ouest de la France / Polliniferous and melliferous resources available for honeybees (Apis mellifera) in a rural landscape of North-Western France

Piroux, Mélanie 21 October 2014 (has links)
Depuis le début du XXème siècle, l’évolution de l’agriculture et l'intensification des pratiques agricoles ont conduit à des modifications profondes du paysage induisant des pertes importantes d’habitats naturels et semi-naturels. Ces changements, entraînant notamment la diminution des ressources végétales et impliquant l'utilisation systématique de pesticides, ont des répercussions sur les colonies d’abeilles. C’est dans ce contexte que, durant deux saisons apicoles, des inventaires botaniques ont été réalisés au sein de l’aire de butinage de deux ruchers situés en paysage de grande culture du nord-ouest de la France et que des échantillons de pelotes de pollen et de miels prélevés dans ces ruchers ont été analysés. L’objectif était de comparer les ressources floristiques disponibles et celles réellement exploitées par les abeilles et d’entrevoir les stratégies de butinage mises en place dans ce cadre paysager. Les relevés floristiques ont permis de distinguer d’une part, de larges surfaces d’espèces cultivées, à floraison ponctuelle et d’autre part, des surfaces non cultivées, de plus petite taille, occupées par de nombreuses espèces sauvages dont la floraison s’étale sur la totalité de la saison apicole. Les analyses palynologiques montrent que ces espèces floristiques sauvages sont exploitées en continu y compris pendant la période de floraison des espèces cultivées. Bien que cette étude ne soit pas en mesure de le démontrer, il est possible que les espèces sauvages procurent aux colonies un apport nutritionnel que la floraison ponctuelle des plantes cultivées ne peut totalement compenser. Une meilleure connaissance de la valeur nutritionnelle des différents pollens d’essences végétales, ainsi que des besoins alimentaires basiques nécessaires au développement et à la pérennisation des colonies devraient aider à éprouver cette hypothèse. / Since the beginning of the XXth century, the evolution of agriculture and the intensification of farming practices have led to landscape changes with the loss of natural and semi-natural habitats. These changes, involving a decrease of plant resources and a use of pesticides, may have noticeable impact on honey bee colonies. In this framework of weakened biodiversity, the initiative was taken of recording botanical species growing in the foraging area of two apiaries in cultivated landscapes of Western France and sampling pollen pellets and honey for pollen species determination during two successive beekeeping seasons. The aim of this study was to compare the available flora resources with those really exploited by the honey bees, to get a glimpse of the foraging strategies developed by the colonies in this landscape context. The floristic readings enabled to distinguish wide areas of cultivated plant species characterized by temporary blossoms from areas of wild species characterized by much smaller superficies and by flowerings spread over the year. Palynological analyses indicate that wild floristic species are exploited throughout the beekeeping season including during blooms of cultivated plant species. Even though not conclusively stated by the present study, it is possible that wild species provide colonies with nutritional intakes that cannot be totally compensated by temporary blooms of cultivated plants. A more extended knowledge of the nutritional values of pollens produced by plant species together with a better understanding of basic food needs for development and perennisation of colonies should help to test this hypothesis.
377

Caracterização do potencial bioativo do pólen apícola de Eucalyptus sp. in vitro e sua influência sobre parâmetros de estresse oxidativo e de inflamação in vivo / Characterization of bioactive potential of bee pollen from Eucalyptus sp. in vitro and its influence on parameters of oxidative stress and inflammation in vivo

José Augusto Gasparotto Sattler 18 October 2018 (has links)
O presente trabalho teve por objetivo caracterizar os compostos bioativos e o impacto de fatores climáticos no pólen apícola (PA) de Eucalyptus sp., o seu potencial antioxidante in vitro e a sua influência em parâmetros do estresse oxidativo e da inflamação in vivo. A caracterização quimica das amostras foi realizada pela quantificação de fenólicos e flavonóides totais e a avaliação da atividade antioxidante dos extratos por três metodologias (DPPH, ORAC e FRAP). Foram realizadas análises de perfil de ácidos graxos e fitoesteróis (CG). Os resultados de fenólicos e flavonóides totais mostraram uma variação entre 17 e 44 mg de equivalentes de ácido gálico e entre 1,3 e 4,4 mg de equivalentes de catequina/g. A atividade antioxidante mostrou uma variação de 267 a 961 &#181;mol de equivalentes de Trolox/g pelo método ORAC, de 38 a 147 &#181;mol de equivalentes de Trolox/g para o FRAP e um EC50 entre 0,41 e 1,61 mg/mL de extrato por DPPH. Apesar das amostras de PA apresentarem baixa quantidade de lipideos (3,3 %), em torno de 50 % do total destes são constituidos de ácidos graxos insaturados. Foram encontrados teores de fitoesteróis entre 1,2 a 1,8 mg/g (sitoesterol, estigmasterol e campesterol). Estes resultados confirmaram a presenca de bioativos com potencial antioxidante nas amostras. A fim de confirmar seu efeito biológico, foi selecionada uma amostra para a realização do ensaio in vivo, na qual foram identificados por CLAE três compostos fenólicos majoritários (rutina, 3n-tris-p-feruloil-espermidina e miricetina). O ensaio foi realizado por 10 semanas com 70 camundongos machos (C57BL/6), distribuídos em sete grupos de 10 animais cada: controle normolipídico (NL); controle hiperlipídico (HL); dieta NL com 5 % de PA; dieta HL com 2,5 % de PA; dieta HL com 5 % de PA; dieta HL com extrato de PA (EPA) a 2,5 %; e dieta HL com EPA a 5 %. Foi possível identificar que os grupos HL tiveram maior ganho de peso quando comparados aos grupos NL (p<0,05), porem os grupos com incorporação de PA não apresentaram diferencas em relação ao controle HL. Foram avaliados ainda parâmetros bioquímicos séricos, de estresse oxidativo (ORAC, TBARS, GSH e enzimas antioxidantes) e parâmetros inflamatórios (IL1-&#946;, IL-6, IL-10, MCP-1 e TNF-&#945;) no tecido hepático. Os resultados de parâmetros de estresse oxidativo não apresentaram diferenças significativas entre os grupos. Quanto aos parâmetros inflamatórios os grupos HL+PA2,5 e HL+PA5 reduziram os níveis das citocinas IL1-&#946;, IL-6 e MCP-1 (p<0,05) e TNF-&#945; apenas o grupo HL+PA5 % apresentou uma redução significativa (p<0,05). Os resultados de citocinas inflamatórias mostraram um efeito positivo na administração de PA, visto que ocorreu uma diminuição nos níveis do tecido hepático dos animais. Estes resultados mostraram que o PA promoveu uma melhora do quadro inflamatório ocasionado com uma dieta hiperlipídica. / The present work aimed to characterize bioactive compounds and the impact of climatic factors on the bee pollen (BP) from Eucalyptus sp., its antioxidant potential in vitro and its influence on parameters of oxidative stress and inflammation in vivo. The chemical characterization of the samples was performed by the quantification of phenolics and flavonoids, and evaluation of the antioxidant activity of the extracts by three methodologies (DPPH, ORAC and FRAP). Profile of fatty acids and phytosterols were performed by gas chromatography (GC). The results of phenolics and flavonoids varied between 17 and 44 mg of gallic acid equivalents and between 1.3 and 4.4 mg of catechin equivalents/g. The antioxidant activity varied from 267 to 961 &#181;mol of Trolox equivalents/g by the ORAC method, from 38 to 147 &#181;mol of Trolox equivalents/g for FRAP and an EC50 between 0.41 and 1.61 mL of extract/mg by DPPH. Despite the low lipid content of PA samples (3.3%), around 50% of the total is composed of unsaturated fatty acids. Phytosterols levels were found between 1.2 and 1.8 mg/g (sitosterol, stigmasterol and campesterol). This result confirms the presence of bioactive compounds with antioxidant potential in the samples. In order to evaluate its biological effect, a sample was included in the in vivo assays, in which three phenolic compounds (rutin, 3n-tri-p-feruloyl-spermidine and myricetin) were identified. The assay was performed for 10 weeks with 70 male mice (C57BL/6), distributed in seven groups of 10 animals each: normolipid control (NL); hyperlipidemic control (HL); diet NL with 5% of BP; HL diet with 2.5% BP; HL diet with 5% BP; HL diet with 2.5% BP extract (BPE); and HL diet with 5% BPE. The HL groups gained more weight compared with the NL groups (p<0.05), but the groups supplemented with BP did not show lower weight compared to the HL groups. Serum biochemical parameters of oxidative stress in hepatic tissue (ORAC, TBARS, GSH and antioxidant enzymes) and inflammation (IL-&#946;, IL-6, IL- 6, IL-10, MCP-1 and TNF-&#945;) were evaluated. The levels of oxidative stress did not show differences between the groups. HL + PA2.5 and HL + PA5 reduced the cytokines IL1-&#946;, IL-6 and MCP-1 (p<0.05) and TNF-&#945; only the HL + PA5 group showed a significant reduction (p<0.05). The cytokine results showed a positive reduction with BP administration, with a decreasing rate in the hepatic animal tissues. This results showed that BP promotes an improvement in the inflammatory status, occurred by a hyperlipidic diet.
378

Pólen apícola desidratado: composição físico-química, qualidade microbiologica, compostos fenólicos e flavonoides, capacidade antioxidante e origem botânica / Dehydrtated bee pollen: physicochemical, microbiological quality, phenolic and flavonoids compounds, antioxidant and botanical origin.

Vanilda Aparecida Soares de Arruda 10 October 2013 (has links)
O pólen apícola, produto da aglutinação do pólen das flores com néctar e substâncias salivares das abelhas, tem sido promovido como suplemento da dieta humana por apresentar propriedades nutricionais e bioativas. Sessenta e duas amostras de pólen apícola desidratado foram avaliadas para as análises de compostos fenólicos, flavonoides, atividade antioxidante por três métodos (DPPH, sistema &#946;-caroteno e ORAC), origem botânica, qualidade comercial (umidade, cinzas, lipídeos, proteínas e carboidratos) e sanitária (bolores e leveduras, aeróbios mesófilos, coliformes totais, E.coli, clostrídios sulfito redutores e S.aureus.), além da atividade antimicrobiana (Candida albicans, Escherichia coli, Staphylococcus aureus). Os valores obtidos para compostos fenólicos e flavonoides totais variaram de 12,60 a 84,22 mg GAE/g de pólen apícola (GAE: equivalentes em ácido gálico) e 1,90 a 36,85 mg de quercetina/g de pólen apícola respectivamente. O EC50, determinado pelo método do DPPH, variou de 0,35 a 13,42 mg pólen apícola/mL de extrato. Os extratos de pólen apícola apresentaram valores entre 52,58 e 98,37 % para o método do &#946;-caroteno. Quando quantificada por ORAC, a atividade antioxidante medida ficou entre 132,98 e 575,85 &#181;mol eq. trolox/g pólen apícola. Na avaliação da qualidade comercial foram obtidos os valores de 3,06% a 8,12% para umidade, de 1,94 a 4,61%, para cinzas, de 3,35 a 10,96% para lipídeos; de 17,73 a 34,73% para as proteínas, de 11,86 a 25,71% e de 2,77 a 15,87% para os açúcares frutose e glicose, respectivamente. Verificou-se que a presença do pólen apícola inibiu o crescimento de todos os microrganismos estudados. Candida albicans foi a mais resistente e o Staphylococcus epidermides foi o mais sensível. Observou-se 36 tipos polínicos diferentes, destacando-se: Cocos nucifera sp., Mimosa scabrella (Benth.), Mimosa caesalpiniaefolia sp., Eucalyptus sp., Myrcia sp., Asteraceae, Poaceae., Euphorbiaceae e Brassica que ocorreram com maior frequência entre as amostras estudadas. Foram observadas somente correlações moderadas e fracas entre os tipos polínicos presentes e os parâmetros avaliados para as amostras desidratadas de pólen apícola. / Bee pollen, a product of agglutination of flower pollen with nectar and bee salivary substances, has been promoted as a dietary supplement for human because of its nutritional and bioactive properties. Sixty-two samples of dehydrated bee pollen were analyzed for phenolics, flavonoids, antioxidant activity using three methods (DPPH, &#946;carotene and ORAC), botanical composition, commercial quality (moisture, ashes, lipids, proteins, carbohydrates), hygiene (aerobic mesophiles, yeasts and moulds, coliforms, Escherichia coli, Staphylococcus aureus and sulfite-reducing Clostridium), and antimicrobial activity (Candida albicans, Escherichia coli, Staphylococcus aureus). The obtained values for total phenolics ranged from 12.60 to 84.22 mg GAE/g bee pollen (GAE: gallic acid equivalents) while for total flavonoids ranged from 1.90 and 36.85 mg quercetin/g bee pollen. The EC50, determined by the DPPH method, ranged from 0.35 to 13.42 mg bee pollen/ml of extract. The bee pollen extracts showed values between 52.58 and 98.37% by &#946;- carotene method. When measured by ORAC, antioxidant activity was between 132.98 and 575.85 &#181;mols eq. trolox/g bee pollen. In the evaluation of commercial quality, the following results were achieved: 3.06% to 8.12% for moisture, 1.94 to 4.61% for ashes, 3.35 to 10.96% for lipids, 17.73 to 34.73% for proteins, from 11.86 to 25.71% and 2.77 to 15.87% for the carbohydrates glucose and fructose respectively. It was verified that the presence of the bee pollen inhibited the growth of all microorganisms studied. Candida albicans was the more resistant and Staphylococcus epidermides the more sensitive. Thirty-three pollen-types were identified mainly Cocos nucifera sp., Mimosa scabrella (Benth.) sp., Mimosa caesalpiniaefolia sp., Eucalyptus sp., Myrcia sp., Asteraceae sp., Poaceae sp., Euphorbiaceae sp. and Brassica sp. that occurred more frequently among the samples studied. It was observed only moderate and weak correlations between the pollen types present and the evaluated parameters for dehydrated samples of bee pollen
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Prévalence d’agents pathogènes de l’abeille domestique (Apis mellifera) au Québec et leur impact sur la mortalité hivernale

Claing, Gabrielle 08 1900 (has links)
No description available.
380

Gelové polymerní elektrolyty s retardéry hoření / Gel polymer electrolytes with fire retardands

Veselkova, Iuliia January 2017 (has links)
This graduate work deals with the study and preparation of gel polymer electrolytes with flame retardants for lithium-ion batteries. The theoretical part describes the types of electrolytes, their features, benefits, how they differ and where they are used in detail. The basis of this section is gel electrolytes with flame retardants, to measure their electrical and electrochemical properties. The experimental part deals with the preparation of samples of gel electrolytes with different percentages of flame retardant, where varied species of flame retardants and measuring their electrical conductivity and potential windows. Impedance spectroscopy, cyclic voltammetry and dynamic-analytical thermal analysis were selected as measuring methods.

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