Dissertations / Theses on the topic 'POLKON'

O poliuretano (PU) representa um dos grupos mais importantes de polímeros, com uma grande variedade de tipos e alta versatilidade de aplicações. É uma classe de polímeros na qual as unidades formadoras da cadeia polimérica são interligadas por ligações uretânicas, -O(CO)(NH)- . As macromoléculas são formadas pela reação de pré-polímeros contendo grupos terminais hidroxila com di-isocianatos. Quando excesso de diisocianato é empregado, a macromolécula resultante terá, em suas extremidades, grupos isocianato que podem então reagir com diferentes dióis poliméricos para extender adicionalmente as cadeias, ou com trióis para formar ligações cruzadas (Allcock et al., 2003). Devido a alta versatilidade do poliuretano e por ser o principal componente de produtos de alto consumo como colchões e geladeiras, o volume de resíduo de PU gerado é cada vez maior e por se tratar de um termo-fixo sua reciclagem não é um processo simples. O objetivo do presente trabalho é analisar os efeitos do uso de um poliol reciclado através de um processo de glicólise especifico nas propriedades mecânicas de uma espuma rígida de poliuretano. Diversos métodos de glicólise foram analisados da literatura e com base nas informações encontradas uma rota ótima foi proposta/escolhida. O produto gerado foi então caracterizado e utilizado em diferentes proporções em substituição ao poliol base em formulações padrão de espumas rígidas de poliuretano, de forma que os efeitos da adição do mesmo sobre as características finais relevantes da espuma pudessem ser observadas. O processo de reciclagem apresentado no presente estudo mostrou-se um processo efetivo no tratamento de resíduos industriais de espuma de poliuretano rígido, uma vez que o processo é rápido, de custo relativamente baixo e produz um produto final de qualidade comparável ao dos produtos virgens existentes no mercado. A funcionalidade e número de OH superiores do poliol recuperado trazem inclusive melhorias na estrutura mecânica da espuma final obtida a partir do uso do mesmo. A presença de impurezas advindas de reações secundárias mostraram sua influência na alteração da reatividade da reação de formação da espuma de poliuretano, porém este fato pôde ser ajustado através de alterações no nível de catalisadores adicionados a formulação.<br>The polyurethane (PU) represents one of the most important groups of polymers, with very versatile types and applications. It is a class of polymers in which the polymeric chain components are linked by uretanic linkages, -O(CO)(NH)-. The macromolecules are formed by the reaction of pre-polymers containg hydroxyl end groups with di- isocyanates. When excess of Isocyanate is used, the resulting macromolecule will have, in its edges, isocyanate groups that can react with different polymeric diols to extent additionally the chains, or with triols to form cross-linked polymers. (Allcock et al., 2003) The unlimited nature of the components A and B plus the several applications makes the PU one of the most versatile plastics. Due to its high versatility and for being the main component in mass consumption products like refrigerators and mattresses, the volume of PU residues generated is each time higher and once it is a thermoset its recycling methods are not easy. The objective of the present work is analyzing the effects of the use of a recycled polyol obtained through a specific glycolysis process in the mechanical properties of rigid PU foam. Different glycolysis methods were analyzed from previous art and an ideal route was established. The recycled polyol was characterized and used in different proportions in substitution of the conventional polyol in standard formulations for rigid foam production, thus the effects of this substitution could be observed. The proposed recycling process showed to be very effective in the recovering of polyols from PU rigid foam residues, once the process is fast, relatively low cost and produces a final product with equivalent quality of a conventional polyol. The higher functionality and OH number of the recovered polyol brings to the final foam superior mechanical properties. The presence of secondary products like primary amines generated in the process could be noticed by the increase in the reactivity of the formulations using the recycled polyol, although this fact was proved to be manageable through adjustments in the aminic catalyst add to the formulations.

Made available in DSpace on 2014-06-11T19:33:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-09Bitstream added on 2014-06-13T18:45:42Z : No. of bitstreams: 1 iossi_e_dr_jabo.pdf: 3984736 bytes, checksum: da09658a2704c557f92e85a8f193bb03 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Os objetivos dessa pesquisa foram os de estudar a morfologia floral, o ponto de maturidade fisiológica das sementes de Phoenix roebelenii (tamareira-anã) e o período de colheita dos frutos, no qual as sementes apresentem máxima qualidade fisiológica. As flores femininas e masculinas foram esquematizadas com o auxílio de uma câmara clara acoplada ao estereomicroscópio. Os grãos de pólen foram observados e fotografados em microscópio eletrônico de varredura. Os frutos, a partir de sua formação, foram colhidos semanalmente, sendo as determinações feitas em laboratório. Os dados biométricos dos frutos e das sementes foram determinados com auxílio de paquímetro digital. Foram também determinados o teor de água, a matéria verde e a matéria seca dos frutos e das sementes, a porcentagem de germinação e o índice de velocidade de germinação das sementes. As variáveis que apresentaram crescimento em função do tempo foram ajustadas ao modelo logístico e aquelas com tendência decrescente em função do tempo foram ajustadas ao modelo exponencial decrescente. A morfologia das flores masculinas, femininas e dos grãos de pólen de P. roebelenii é bastante homogênea e confiável, podendo ser usada no reconhecimento e identificação dessa espécie, além de fornecer subsídios para estudos da sua biologia floral e reprodutiva. O ponto de maturidade fisiológica das sementes de P. roebelenii ocorreu aos 138 dias após a antese (d.a.a.), podendo o período de colheita ser estendido até os 194 d.a.a.<br>The objectives of this research were to study the floral morphology and the physiological maturation of Phoenix roebelenii seeds, for the determination of the ideal harvesting time. The pistillate and staminate flowers were schematized with a clear camera coupled to the stereomicroscope, and the pollen grains were documented by means of electronic spin microscope. The fruits, after its formation, were harvested weekly and they were evaluated at laboratory conditions. Biometrical data of the fruits and seeds were obtained. The moisture content, the fresh and dry weight from the fruits and seeds, and the seed germination and the speed of germination index (SGI) were also recorded. The variables which showed growth in function of the time were adjusted to a logistic model and the one's which exhibited a decrescent trend in the function of the time were adjusted to an exponential decrescent model. The morphology of the flowers, and of the pollen grains of P. roebelenii is sufficiently homogeneous and trustworthy, being able to be used for the recognition and identification of this species, besides supplying subsidies studies of its floral and reproductive biology. It was observed that the physiological maturation point of seeds of P.roebelenii occurred at 138 days after anthesis (d.a.a.), and the harvesting period could be extended up to 194 d.a.a.

Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-06-28T19:58:26Z No. of bitstreams: 1 FICHA_CATALOGR?FICA_EMBUTIDA_Disserta??o Cristiano_Jaeger Stradolini_Processo Poliol.pdf: 3080490 bytes, checksum: 6539be3aad396dd1f8b30cd3389b1469 (MD5)<br>Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-06T13:07:04Z (GMT) No. of bitstreams: 1 FICHA_CATALOGR?FICA_EMBUTIDA_Disserta??o Cristiano_Jaeger Stradolini_Processo Poliol.pdf: 3080490 bytes, checksum: 6539be3aad396dd1f8b30cd3389b1469 (MD5)<br>Made available in DSpace on 2018-07-06T13:12:44Z (GMT). No. of bitstreams: 1 FICHA_CATALOGR?FICA_EMBUTIDA_Disserta??o Cristiano_Jaeger Stradolini_Processo Poliol.pdf: 3080490 bytes, checksum: 6539be3aad396dd1f8b30cd3389b1469 (MD5) Previous issue date: 2018-03-22<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES<br>During the past few years, nanosized noble metals have attracted much attention due to their unique electrical and physical properties. Among them, silver has been the subject of several studies, by having the highest electrical and thermal conductivity between all metals. For that reason, its one-dimensional nanometric structure (nanowires) has been receiving a lot of attention, due to its potential in the manufacture of devices that offer good electrical conduction and optical transparency. There are several methods of synthesis for the production of these silver nanowires, however the most widely used is the polyol process, due to its simplicity and low cost. Several studies show the influence of different parameters of the polyol process (reaction time, temperature and etc.) on the final morphology of the nanowires. Thus, a well-defined protocol of good practice for obtaining long and thin silver nanowires is required. The main objective of this work is the development of a low cost protocol capable of generating nanowires with great lengths by modifying the polyol process parameters. Variations were also performed in the method of addition of the main synthesis reagent, silver nitrate, and its influence on the final morphology of the silver nanowires was studied. In this work, by using the polyol process, nanowires up to 40 ?m in length were reported, demonstrating the effectiveness of the developed technique and conclusions about the final results were presented.<br>Ao decorrer dos ?ltimos anos, metais nobres na escala nanom?trica t?m atra?do muita aten??o, devido as suas propriedades el?tricas e f?sicas ?nicas. Dentre eles, a prata vem sendo alvo de diversos estudos, por possuir a maior condutividade el?trica e t?rmica entre todos os metais. Por conta disto, sua estrutura nanom?trica unidimensional (nanofios) vem recebendo muita aten??o, pelo seu potencial na fabrica??o de dispositivos que exijam alta condutividade el?trica e transpar?ncia ?ptica. Atualmente, existem diversos m?todos de s?nteses para a produ??o destes nanofios de prata, por?m o mais utilizado ? o processo poliol, por ser simples e de baixo custo. Diversos estudos demonstram a influ?ncia de diferentes par?metros do processo poliol (tempo de rea??o, temperatura e etc.) sobre a morfologia final dos nanofios. Assim, se faz necess?rio um protocolo bem definido de boas pr?ticas para a obten??o de fios longos e finos. O principal objetivo deste trabalho ? o desenvolvimento de um protocolo de baixo custo capaz de gerar nanofios com grandes comprimentos, atrav?s de altera??es nas vari?veis do processo poliol, como, por exemplo, varia??es no m?todo de adi??o do principal reagente da s?ntese, o nitrato de prata. Foi estudada a sua influ?ncia na morfologia final dos nanofios. Neste trabalho, os resultados finais apresentaram que nanofios de at? 40 ?m de comprimento foram produzidos pelo processo poliol, demonstrando a efic?cia da t?cnica desenvolvida e foram apresentadas as conclus?es acerca dos resultados atingidos.

Le titre de notre article est une formulation métaphorique de la problématique qui est discutée, partant du principe qu´un des fondements d´une vie de couple harmonieuse est une bonne enente entre les partenaires.

Orientador: Leila Trevisan Braz<br>Resumo: Polinizações manuais na cultura do meloeiro apresentam taxa de sucesso de cerca de 40%, entretanto, pouco se relata na literatura sobre os aspectos que afetam esta taxa, tornando-a baixa, e como incrementa-la. Este trabalho teve por objetivo estudar a biologia reprodutiva do meloeiro, e estratégias para aumentar a taxa de pegamento de frutos na cultura. Para tal, foram estudados a viabilidade polínica e receptividade estigmática em genótipos de meloeiro ao longo do dia da antese, e, o impacto de diferentes protocolos de polinização na fixação de frutos. Desta forma, foram desenvolvidos três experimentos, um de viabilidade polínica in vitro, e um de receptividade estigmática, estes envolvendo três genótipos de melão rendilhado e cinco horários de coleta de flores, visando entender o comportamento floral do meloeiro ao longo do dia. E um terceiro trabalho, onde foi estudado a fixação de frutos, massa total e massa de mil sementes dos frutos formados sob diferentes protocolos de polinização, para tal empregou-se autopolinizações e hibridações, em dois horários e soluções diretamente nos estigmas da flor hermafrodita, com o objetivo de beneficiar a germinação e estrutura dos tubos polínicos, propiciando fecundações mais eficientes. Após as avaliações, os dados foram submetidos a análise estatística e comparados pelo teste de Tukey a 5% de significância. Foi possível concluir que a viabilidade polínica do meloeiro é afetada pelo genótipo, e os genótipos, JAB 11, JAB 20 e Fantasy, ... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: Manual pollination in melon crop has a success rate of about 40%, however, little is reported in the literature about the aspects that affect this rate, making it low, and how to increase it. This work aimed to study the reproductive biology of melon, and strategies to increase the fruit set rate in the crop. To this end, we studied the pollen viability and stigmatic receptivity in melon genotypes throughout the day of anthesis, and the impact of different pollination protocols on fruit fixation. Thus, three experiments were carried out, one with in vitro pollen viability and one with stigmatic receptivity, involving three tracery melon genotypes and five flower collection schedules, aiming to understand the floral behavior of melon throughout the day. And a third work, where the fruit fixation, total mass and mass of one thousand seeds of the fruits formed under different pollination protocols was studied. in order to benefit the germination and structure of pollen tubes, providing more efficient fertilization. After the evaluations, the data were submitted to statistical analysis and compared by Tukey test at 5% of significance. It was concluded that the pollen viability of melon is affected by genotype, and the genotypes, JAB 11, JAB 20 and Fantasy, used in this work present viability peak at 09am. Stigmas remain receptive throughout the day of anthesis, allowing pollinations to be made throughout the day if pollen is viable. In JAB 20 hermaphrodite flowers, the applicatio... (Complete abstract click electronic access below)<br>Mestre

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior<br>A utilizaÃÃo de resÃduos agroindustriais como matÃria-prima para obtenÃÃo de produtos com maior valor agregado tem recebido grande destaque no campo cientÃfico nos Ãltimos anos. Esses materiais sÃo descartados no ambiente, conduzindo a prejuÃzos ambientais de grandes proporÃÃes ou, quando utilizados, nÃo sÃo empregados de forma plena e sustentÃvel. O Brasil se destaca na produÃÃo agrÃcola mundial de diversos produtos, sendo a regiÃo nordeste a maior produtora nacional de caju, incluindo assim o paÃs em uma situaÃÃo de destaque global em relaÃÃo a esse cultivo. No processamento, retira-se a amÃndoa do caju, que em geral à exportada com excelente preÃo de mercado, e extrai-se o suco, restando uma considerÃvel quantidade de bagaÃo. Esse componente, por sua vez, possui preÃo comercial irrisÃrio podendo ser utilizado na adubaÃÃo e em complemento a alimentaÃÃo animal. O bagaÃo do caju (BC) à rico em celulose (17,73%) e hemicelulose (19,22%), o que o torna um material lignocelulÃsico apto para obtenÃÃo de diversos aÃÃcares fermentescÃveis, especialmente a glicose e a xilose. Esses carboidratos podem ser assimilados por micro-organismos originando, por meio da via biotecnolÃgica, diversos bioprodutos, como por exemplo o xilitol. Essa substÃncia à um poliol com importÃncia alimentÃcia, farmacÃutica e odontolÃgica obtida a partir da D-xilose. Sua produÃÃo industrial ocorre a partir da hidrogenaÃÃo, catalisada pela presenÃa de ligas metÃlicas, da D-xilose, sob condiÃÃes de elevadas temperaturas e pressÃes, o que eleva o custo do processo. Diversos micro-organismos, principalmente leveduras, sÃo reportados por sua capacidade em produzir xilitol a partir de resÃduos lignocelulÃsicos. Dessa maneira, o objetivo desse trabalho foi realizar um estudo pioneiro a respeito da empregabilidade do BC como substrato para a produÃÃo de xilitol por fermentaÃÃo microbiana. A primeira etapa da pesquisa avaliou a produÃÃo de xilitol em meios sintÃticos, compostos por xilose (MX) ou xilose e glicose (MXG), por trÃs leveduras: Candida tropicalis, Kluyveromyces marxianus CCA510 e Kluyveromyces marxianus ATCC36907. As trÃs leveduras foram capazes de produzir xilitol nos meios sintÃticos e C. tropicalis e K. marxianus CCA510 foram selecionadas pelo seu melhor desempenho para os experimentos seguintes. A segunda etapa do trabalho consistiu em avaliar a produÃÃo de xilitol a partir do hidrolisado hemicelulÃsico de bagaÃo de caju (HBC). O hidrolisado foi obtido submetendo-se o BC, apÃs prÃvia lavagem, secagem e padronizaÃÃo de tamanho, a hidrÃlise Ãcida com H2SO4 0,6 mol.L-1, alcanÃando concentraÃÃo de glicose e xilose de 12,09 g.L-1 e 19,02 g.L-1, respectivamente. O HBC foi concentrado por evaporaÃÃo e tratado com dois tipos de carvÃo ativado (em grÃnulos e em pÃ), observando-se que o carvÃo em pà foi mais eficiente para eliminaÃÃo de inibidores do processo microbiana (como Ãcido acÃtico, fÃrmico e compostos fenÃlicos). Por Ãltimo, avaliou-se a influÃncia da suplementaÃÃo do HBC com diferentes fontes de nitrogÃnio (ureia, sulfato de amÃnio e extrato de levedura) para a produÃÃo de xilitol. Concluiu-se que a ureia foi capaz de melhorar o crescimento em biomassa dos micro-organismos testados, contudo, nenhuma das fontes de nitrogÃnio foi significativas para o incremento da produÃÃo de xilitol. Diante do estudo, pode-se concluir que o HBC pode ser matÃria-prima potencial para a produÃÃo biotecnolÃgica de xilitol pelas leveduras empregadas e que tratamentos de destoxificaÃÃo e suplementaÃÃo nutricional podem ser levados em consideraÃÃo para melhoria do processo.

Resumo: Os objetivos dessa pesquisa foram os de estudar a morfologia floral, o ponto de maturidade fisiológica das sementes de Phoenix roebelenii (tamareira-anã) e o período de colheita dos frutos, no qual as sementes apresentem máxima qualidade fisiológica. As flores femininas e masculinas foram esquematizadas com o auxílio de uma câmara clara acoplada ao estereomicroscópio. Os grãos de pólen foram observados e fotografados em microscópio eletrônico de varredura. Os frutos, a partir de sua formação, foram colhidos semanalmente, sendo as determinações feitas em laboratório. Os dados biométricos dos frutos e das sementes foram determinados com auxílio de paquímetro digital. Foram também determinados o teor de água, a matéria verde e a matéria seca dos frutos e das sementes, a porcentagem de germinação e o índice de velocidade de germinação das sementes. As variáveis que apresentaram crescimento em função do tempo foram ajustadas ao modelo logístico e aquelas com tendência decrescente em função do tempo foram ajustadas ao modelo exponencial decrescente. A morfologia das flores masculinas, femininas e dos grãos de pólen de P. roebelenii é bastante homogênea e confiável, podendo ser usada no reconhecimento e identificação dessa espécie, além de fornecer subsídios para estudos da sua biologia floral e reprodutiva. O ponto de maturidade fisiológica das sementes de P. roebelenii ocorreu aos 138 dias após a antese (d.a.a.), podendo o período de colheita ser estendido até os 194 d.a.a.<br>Abstract: The objectives of this research were to study the floral morphology and the physiological maturation of Phoenix roebelenii seeds, for the determination of the ideal harvesting time. The pistillate and staminate flowers were schematized with a clear camera coupled to the stereomicroscope, and the pollen grains were documented by means of electronic spin microscope. The fruits, after its formation, were harvested weekly and they were evaluated at laboratory conditions. Biometrical data of the fruits and seeds were obtained. The moisture content, the fresh and dry weight from the fruits and seeds, and the seed germination and the speed of germination index (SGI) were also recorded. The variables which showed growth in function of the time were adjusted to a logistic model and the one's which exhibited a decrescent trend in the function of the time were adjusted to an exponential decrescent model. The morphology of the flowers, and of the pollen grains of P. roebelenii is sufficiently homogeneous and trustworthy, being able to be used for the recognition and identification of this species, besides supplying subsidies studies of its floral and reproductive biology. It was observed that the physiological maturation point of seeds of P.roebelenii occurred at 138 days after anthesis (d.a.a.), and the harvesting period could be extended up to 194 d.a.a.<br>Orientador: Rubens Sader<br>Coorientador: Fabíola Vitti Môro<br>Banca: Taís Tostes Graziano<br>Banca: Luciana Rossini Pinto<br>Banca: Sérgio Valiengo Valeri<br>Banca: Carlos Ferreira Damião Filho<br>Doutor

Diploma thesis focuses on a problematics of an optical networks in terms of an optical cables laying and a work with individual fibers. Thesis contains an basic physical properties which are used in a fiber optics. Methodology of correct working procedures used in fiber optics is discussed at the same time. Thesis also contains detailed documentation of realized optical connections including scheme of realized outdoor connection. 3D design of an rack case is also part of the thesis. Rack case provides an option to simulate plenty of different lengths of optical routes. Rack case is designed in 6U variant.

Estudiar els productes d’ Apis mellifera derivats dels recursos botànics (mel, melat, pol·len i pròpoli), és útil per a caracteritzar i posar en valor els productes de l’ abella d’ un territori i per a comprendre les interaccions planta-pol·linitzador. La melisopalinologia té com a objectius la determinació geogràfica i botànica dels productes apícoles, basant-se en la presencia de tipus pol·línics (TP). El primer objectiu de la present tesi ha estat determinar quines plantes són útils per a A. mellifera a Catalunya, a través d’una revisió bibliogràfica i d’observacions in situ s’ha elaborat una llista de 424 tàxons útils, de 114 famílies. Per a l’estudi melissopalinològic de les 51 mels i els 26 pròpolis analitzats en aquesta tesi es va elaborar una palinoteca de referència en base als TP dels tàxons d’interès apícola de Catalunya. Com a resultat de l’anàlisi melissopalinològica, s’ha determinat l’origen geogràfic i botànic de les mels i els pròpolis, i s’han identificat 156 TP de 74 famílies. A través de l’anàlisi de l’espectre pol·línic de les mels, s’ han tipificat diferents tipus de mels, tant multiflorals com monoflorals, de diferents zones geogràfiques i de diferents anys. A més, l’anàlisi estadística ha mostrat l’existència de diferències significatives entre les mels urbanes i la resta de mels. A les mels no urbanes s’han identificat 131 TP. Tot i que els més freqüents són autòctons (Brassicaceae T., Coronilla T., Quercus perennifolio, Rubus T., Salix sp. y Ulex T.), l’aparició d’espècies invasores (com Ailanthus altissima) mostra la seva utilitat com a recurs apícola, i indica que cal tenir en compte a aquest tipus d’espècies a l’hora d’establir l’origen geogràfic i botànic de les mels d’ un territori. També, destacar l’elevada presència i percentatges de TP com Cistus monspeliensis, Hedera helix, Rhamnus sp. i Salix sp., que podrien servir com a indicadors per a la tipificació geogràfica de mels de Catalunya. Per altra banda, es veu reflectida la importància per a A. mellifera dels ecosistemes de tipus matollar i herbaci, així com, que les abelles de ruscs situats a la perifèria de nuclis urbans s’ endinsen a les ciutats per alimentar-se, mentres que les de ruscs urbans poden allunyar-se de la ciutat. En les mels urbanes, procedents de Barcelona i Viladecans, s’han identificat 89 TP, tant ornamentals com silvestres. L’ aparició dels TP Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. i Sophora sp., fan palesa la marcada influència de tàxons exòtics. D’altra banda, l’aparició d’un alt percentatge de tàxons arvenses indica que A. mellifera els visita, i reflecteix la importància de minimitzar l’ús d’ herbicides, i la d’adequar sòls amb aquest tipus de vegetació en ciutats. Referent als pròpolis, l’espectre pol·línic reflecteix la variabilitat de paisatges i vegetació de Catalunya. Es van analitzar 26 mostres que van permetre la determinació de 135 TP, dels quals els més freqüents van ser Asparagus sp., Brassicaceae T., Hedera helix, Quercus perennifoli y Rosmarinus officinalis. A més, les diferències observades en els pròpolis de Catalunya en funció del seu color i textura, podrien estar relacionades amb l’origen botànic de les resines procedents de Pinus sp., Quercus sp, Castanea sativa i Populus sp. Comparant les mostres de pròpolis i mel d’un mateix lloc, s’observa que la riquesa i la diversitat pol·línica és major en pròpolis que en mels i, encara que hi ha relació entre els seus espectres pol·línics, els tipus pol·línics difereixen en un 64,4%. Per això, l’estudi de l’espectre pol·línic de tots dos productes aporta una informació més precisa sobre la vegetació circumdant dels abellars, complementant i millorant la determinació de l’origen geogràfic de mels, sobretot, d’ aquelles amb una diversitat pol·línica molt baixa.<br>Estudiar los productos de Apis mellifera derivados de recursos botánicos (miel, mielato, polen y propóleo), es útil para caracterizar y valorar los productos de la abeja de un territorio y para comprender las interacciones planta-polinizador. La melisopalinología tiene como objetivos la determinación geográfica y botánica de los productos apícolas, basándose en la presencia de tipos polínicos (TP). El primer objetivo de la presente tesis ha sido determinar qué plantas son útiles para A. mellifera en Catalunya, a través de una revisión bibliográfica y de observaciones in situ se ha elaborado una relación de 424 taxones útiles, de 114 familias Para el estudio melisopalinológico de las 51 mieles y 26 propóleos analizados en esta tesis se elaboró una palinoteca de referencia en base a los TP de los taxones de interés apícola de Catalunya. Como resultado del análisis melisopalinológico, se ha determinado el origen geográfico y botánico de mieles y propóleos, y se han identificado 156 TP de 74 familias. A través del análisis del espectro polínico de las mieles, se han tipificado distintos tipos de mieles, tanto multiflorales como monoflorales, de diferentes zonas geográficas y distintos años. Además, el análisis estadístico ha mostrado la existencia de diferencias significativas entre las mieles urbanas y el resto de mieles. En las mieles no urbanas, se han identificado 131 TP. Aunque los más frecuentes son autóctonos (Brassicaceae T., Coronilla T., Quercus perennifolio, Rubus T., Salix sp. y Ulex T.) la aparición de especies invasoras (como Ailanthus altissima) muestra su utilidad como recurso apícola, e indica que hay que tener en cuenta a este tipo de especies al establecer el origen geográfico y botánico de las mieles de un territorio. También, destacar la elevada presencia y porcentajes de TP como Cistus monspeliensis, Hedera helix, Rhamnus sp. y Salix sp., que podrían servir como indicadores para la tipificación geográfica de mieles de Catalunya. Por otro lado, se ve reflejada la importancia para A. mellifera de los ecosistemas de tipo matorral y herbáceo, así como que las abejas de la periferia de núcleos urbanos se adentran en las ciudades para alimentarse, mientras que las de colmenas urbanas pueden alejarse de la ciudad. En las mieles urbanas, de Barcelona y Viladecans, se han identificado 89 TP, tanto ornamentales como silvestres. La aparición de los TP Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. y Sophora sp., hacen patente la marcada influencia taxones exóticos. Por otro lado, la aparición de un alto porcentaje de taxones arvenses indica que A. mellifera los visita, y refleja la importancia de minimizar el uso de herbicidas, y la de adecuar suelos con este tipo de vegetación en ciudades. Referente a los propóleos, el espectro polínico refleja la variabilidad de paisajes y vegetación de Catalunya. Se analizaron 26 muestras que permitieron la determinación de 135 TP, de los cuales los más frecuentes fueron Asparagus sp., Brassicaceae T., Hedera helix, Quercus perennifolio y Rosmarinus officinalis. Además, las diferencias observadas en los propóleos de Catalunya en función de su color y textura, podrían estar relacionadas con el origen botánico de las resinas procedentes de Pinus sp., Quercus sp, Castanea sativa y Populus sp. Comparando las muestras de propóleo y miel de un mismo lugar, se observa que la riqueza y la diversidad polínica es mayor en propóleos que en mieles y, aunque existe relación entre sus espectros polínicos difieren en un 64.4%. Por ello, el estudio del espectro polínico de ambos productos aporta una información más precisa sobre la vegetación circundante de los colmenares, complementando y mejorando la determinación del origen geográfico de mieles, sobre todo, aquellas con una diversidad polínica muy baja.<br>The study of Apis mellifera products derived from botanical resources (honey, honeydew honey, corbicular pollen, and propolis) is useful to assess the quality of bee products in a territory and to better understand plant-pollinator interactions. The main objectives of Melissopalynology are the determination of the geographical and botanical origin of bee products, based on the presence of nectariferous and/or polliniferous pollen types (PT). The first objective of this thesis was to determine which plants are useful to A. mellifera in Catalonia, through a literature review as well as on-site observations has been obtained a list of 424 useful taxa from 114 families. For the melissopalynological study of the 51 honeys and 26 propolis analyzed in this thesis, a reference palinotheque was elaborated based on the list of the pollen types (PT) from the taxa with beekeeping interest in Catalonia. As a result of the melissopalynological analysis, the geographical and botanical origin of the honeys and propolis have been determined, and 156 pollen types of 74 families identified. Through the analysis of the pollen spectrum of honeys, different types of honey have been typified, both multifloral and monofloral, from different geographical areas and from different years. In addition, the statistical analysis has demonstrated the existence of significant differences between urban honey and other honey. In non-urban honeys 131 PT were identified. Although the most frequent are native (Brassicaceae T., Coronilla T., Quercus deciduous, Rubus T., Salix sp., and Ulex T.), the appearance of invasive species (such as Ailanthus altissima) shows it&#8217;s as apicultural resource, and indicates that this type of species must be taken into account when establishing the geographical and botanical origin of honeys from a given territory. Also, the high presence and percentages of PT such as Cistus monspeliensis, Hedera helix, Rhamnus sp. and Salix sp. could serve as indicators for the geographical classification of honey from Catalonia. On the other side, it has been reflected the importance for A. mellifera of shrubland and herbaceous ecosystems, as well as that honeybees located on the periphery of urban centers enter the cities to feed, and that bees from urban beehives can move outside the city. In the urban honeys from Barcelona and Viladecans, 89 PT were identified, both ornamental and wild. The presence of Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. and Sophora sp. reveal the marked influence of exotic taxa. On the other hand, the appearance of a high percentage of PT of weed taxa indicates that A. mellifera visits them, and reflects the importance of minimizing the use of herbicides and of implementing soils with this type of vegetation in cities. Regarding propolis, the pollen spectrum reflects the variability of landscapes and vegetation in Catalonia. 26 samples were analyzed, and 135 PT determined, of which the most frequent being Asparagus sp., Brassicaceae T., Hedera helix, Quercus deciduous and Rosmarinus officinalis. Furthermore, the differences observed in the propolis of Catalonia, on the basis of their color and texture, could be related to the botanical origin of the resins from Pinus sp., Quercus sp, Castanea sativa, and Populus sp. Comparing the samples of propolis and honey from the same place, it was observed that the richness and diversity of pollen is greater in propolis than in honey and, although there is a relationship between their pollen spectra, the pollen types differ by 64.4%. Therefore, the study of the pollen spectrum of both products provides more precise information about the surrounding vegetation of the beehives, complementing and improving the determination of the geographical origin of honey, especially those with a very low pollen diversity.

A comunidade de abelhas associada a uma área de cerrado do Campus da Universidade de São Paulo, no município de Pirassununga-SP foi estudada no período de julho de 2000 a julho de 2002, por meio de amostragem sistemática das abelhas em plantas com floração realizadas quinzenalmente, e com concomitante tipificação dos méis produzidos pelas espécies de abelhas que apresentaram um número significativo de indivíduos coletados. Foram coletados 511 indivíduos, pertencentes a 51 espécies e a 31 gêneros de 4 famílias de Apoidea. A comunidade de abelhas no cerrado seguiu o padrão geral encontrado nas comunidades neotropicais, apresentando muitas espécies com poucos indivíduos e poucas espécies com muitos indivíduos. A família Apidae (sensu latu) foi a mais rica em espécies e a mais abundante. Foram encontradas plantas com períodos prolongados de florescimento lado a lado com plantas de períodos curtos, de modo que praticamente o ano todo tem-se plantas em floração, proporcionando recursos tróficos para as abelhas durante todos os meses. As abelhas visitantes foram coletadas em 52,86% das 140 espécies de plantas em floração, sendo a família Asteraceae a que obteve um maior número de espécies de plantas visitadas pelos insetos (18,92%). Didymopanax vinosum (Araliaceae) foi a espécie vegetal com maior número de abelhas visitantes. Nas espécies de meliponídios estudadas obteve-se baixa produção, justificando o número restrito de colônias encontradas nas áreas. Os meses de maior produção de mel, para a Apis mellifera ocorreram de agosto a novembro, em contrapartida entre os meses de dezembro a fevereiro não foi possível a coleta de amostra. As médias dos parâmetros físico-químicos análisados, das amostras de méis provenientes das duas áreas de cerrado, se enquadram nos padrões de normas em vigor. Através das análises polínicas verificou-se que as abelhas também visitaram áreas vizinhas aos locais onde se encontravam as colméias, utilizando-se principalmente de Eucalyptus sp. e Citrus sp.<br>This research deals with the community of bees from the "cerrado" area of the Campus of the University of São Paulo, in Pirassununga, State of São Paulo, Brazil. The bees occurring on flowering plants were fortnightly sampled from July 2000 to July 2002. The honeys produced by the most frequent bee species were characterized as well. The 511 collected specimens were composed by 51 species and 31 genera of 4 families of the Apoidea. The bee community of the "cerrado" followed the same general pattern of the neotropical communities, presenting many species with few individuals and few species with many individuals. The family Apidae ("sensu latu") was the most abundant one with the highest number of species. One observed long flowering period plants together with short flowering ones, thus providing nutritional resources for the bees the year round. Visiting bees were collected in 52.86% of the 140 flowering plant species, most of them (18.92%) from the family Asteraceae. However Didimopanax vinosum (Araliaceae) was the plant species presenting the highest number of visiting bees. Concerning the species of meliponids studied the honey production was low due to the restricted number of colonies found in the area. As to Apis mellifera the honey production was higher from August to November, but it was impossible to collect samples from December to February. The mean of the physicochemical parameters used to analyse the honey samples from the two "cerrado" areas do fit with the standard rules. Through pollen analyses one observed that the bees have visited mainly plants of Eucalyptus sp. and Citrus sp. in the neighboring areas to their hives.

Le titre de notre article est une formulation métaphorique de la problématique qui est discutée, partant du principe qu´un des fondements d´une vie de couple harmonieuse est une bonne enente entre les partenaires.

Orientadores: Susanne Rath, Sonia Claudia do Nascimento de Queiroz<br>Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química<br>Made available in DSpace on 2018-08-26T03:44:24Z (GMT). No. of bitstreams: 1 Oliveira_RenataCabrerade_D.pdf: 3973991 bytes, checksum: 53109a8e29cba1ca926627e521d33fd2 (MD5) Previous issue date: 2014<br>Resumo: O uso frequente e indiscriminado de agrotóxicos na agricultura tem acarretado a presença de resíduos nos alimentos e contaminação ambiental, principalmente em países com grande potencial agrícola, como o Brasil. Para avaliar a presença de resíduos de agrotóxicos no ambiente, as abelhas e os produtos apícolas têm sido apontados como potenciais bioindicadores, podendo ser utilizados para monitorar grandes áreas devido às longas distâncias percorridas. Assim sendo, o potencial do uso do pólen apícola como bioindicador da contaminação ambiental por agrotóxicos foi avaliado neste trabalho. Para isso, foi necessário desenvolver e validar um método analítico para determinação de multirresíduos em pólen apícola, utilizando cromatografia a gás acoplada à espectrometria de massas sequencial (GC-MS/MS). Para definição das condições ótimas de extração, dois processos foram avaliados: o QuEChERS, e o de partição com acetonitrila. O QuEChERS mostrou ser mais eficiente (melhor seletividade e eficiência de extração) e foi validado para a determinação de 27 agrotóxicos. Estudos de sorção mostraram que os agrotóxicos são fortemente sorvidos no pólen. Nas amostras provenientes do apiário experimental na Embrapa em Jaguariúna/SP não foram encontrados níveis quantificáveis dos agrotóxicos pesquisados, enquanto a presença de resíduos de agrotóxicos nas amostras fornecidas por apicultores de Ribeirão Preto/SP foi confirmada e quantificada. Os métodos desenvolvidos e validados mostraram ser eficientes e podem ser utilizados no monitoramento ambiental quanto à presença de resíduos de agrotóxicos. Os resultados confirmam o potencial do pólen apícola como bioindicador de contaminação ambiental por agrotóxicos<br>Abstract: The extensive use of pesticides in agriculture crop has led to the presence of residues in food and environmental contamination, especially in countries with great agricultural potential, such as Brazil. To assess the presence of pesticide residues in the environment, honeybees and bee products have been mentioned as potential bioindicators, which can be used to monitor large areas due to long distances travelled. Therefore, the potential use of bee pollen as a bioindicator of environmental pesticides contamination has been reported in this work. For this it was necessary to develop and validate an analytical method for the determination of multiresidues in pollen, using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). For the definition of optimum extraction conditions, two procedures were evaluated: QuEChERS, and partition with acetonitrile. The QuEChERS proved to be more efficient (improved selectivity and extraction efficiency), and was validated for the determination of 27 pesticides. Sorption studies showed that pesticides are strongly sorbed in pollen. Unquantifiable levels of pesticides surveyed were found in the samples from experimental apiary at Embrapa in Jaguariúna/SP, while the presence of pesticide residues in samples provided by apiarists from Ribeirão Preto/SP was confirmed and quantified. The validated analytical methods proved to be efficient and can be used in environmental monitoring for the presence of pesticide residues. The results confirm the potential of bee pollen as a bioindicator of environmental pesticides contamination<br>Doutorado<br>Quimica Analitica<br>Doutora em Ciências

Made available in DSpace on 2014-06-11T19:26:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-18Bitstream added on 2014-06-13T20:33:52Z : No. of bitstreams: 1 ferreira_ag_me_jabo.pdf: 1060109 bytes, checksum: 053c94d8f7c28f0b88d050104ec93969 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Doze diferentes genótipos de Phaseolus vulgaris (L.), popularmente conhecido como feijão-vagem, obtidos na Universidade Estadual de Goiás (UEG), Ipameri, Goiás, Brasil, foram descritos morfologicamente, citogeneticamente e palinologicamente. Os estudos morfológicos evidenciaram que a maioria das amostras analisadas é semelhante quanto à forma de germinação, forma dos cotilédones, sistema radicular e filotaxia do primeiro par de folhas. As divergências são demonstradas na forma, espessura, comprimento, largura, cor do tegumento da semente e da pigmentação da porção superior do hipocótilo que são formas de se efetivar a classificação entre os vários genótipos. As plântulas são angiospermas, dicotiledôneas, tendo raiz primária glabra, cotilédones livres, peciolados, crassos, planoconvexos, maciços e de coloração verde clara. O epicótilo é cilíndrico e levemente esverdeado. As sementes são exalbuminosas, reniformes ou cubóides, apresentam tegumento em diferentes cores, com germinação do tipo epigéia e fanerocotiledonar. O número cromossômico diplóide é 2n = 22 cromossomos para os doze genótipos. Três amostras mostraram como proposta de cariótipo a formulação 3M + 7SB + 1ST, quatro possuem 6M + 5SB, cinco apresentam formulações cariotípicas divergentes, sendo 5M + 5SB + 1ST, 4M + 6SB + 1ST, 8M + 3SB, 10M + 1SB, 9M + 2SB. A morfologia polínica evidenciou grãos de forma triangular-obtusa com contorno convexo, tricolpados e com protuberâncias relativamente distantes. As diferenças entre esses grãos restringem-se à quantidade de protuberâncias no genótipo 26 e quanto ao tamanho, que varia de 38,33 μm a 31,10 μm de diâmetro.<br>Twelve different genotypes of Phaseolus vulgaris (L.) well-known as green been, obtained at UEG – University of Goiás State, Ipameri, GO Brazil were described morphologically, cytogenetically and palinologically. The morphologic evaluations evidenced a similar germination and cotyledon form, root system, and phyllotaxy in the first pair of leaves in the most of the analyzed samples. De differences appeared in the form, thickness, length, width, seed tegument color, and the hypocotyls superior portion pigmentation that are ways to effectuate the classification among several genotypes. The plantlets are angiosperms, dicotyledonous, have an initial root as glabra, free cotyledon, peciolate, crass, plan-convex, solid, and green-light color. The epicotyls is cylinder and slightly green. The seeds are unalbuminoses, reniforms or cuboids, present tegument in different colors, germination-like epigeous and fanerocotyledonous. The number of diploid chromosome is 2n=22 to all of twelve genotypes. Three samples showed as a cariotype proposal a 3M + 7SB + 1ST formula, while four presented the 6M + 5SB formula, five presented divergent cariotypic formula, being 5M + 5SB + 1ST, 4M + 6SB + 1ST, 8M + 3SB, 10M + 1SB, and 9M + 2SB. The polinic morphology evidenced triangular-obtuse grains shape having convex border, being trycolps and having ridges relatively distant. The differences between these grains are restricted to the ridges amount in the genotype 26 and by the size, varying from 38.33μm to 31.10μm diameter.

Thesis (M.S.)--University of California, San Diego, 2008.<br>Title from first page of PDF file (viewed July 25, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 28-29).

This thesis evaluates some of the most recent and promising approaches for deriving the No Fit Polygon for two simple polygons, possibly with holes, and verify that the approach works in practice. We have chosen three different approaches based on the complexity of the input. These approaches were implemented and benchmarked against CGAL [1], a third party library which provides solvers for many computational geometry problems. Our solution solves problems of a higher degree of complexity than that of the library we benchmarked against and for input of lower complexity we solve the problem in a more efficient manner.<br>Den här uppsatsen evaluerar några av de senaste och mest lovande tillvägagånssätt för att generera No Fit - polygonen för två enkla polygoner, med och utan hål, och verifiera att de fungerar i praktiken. Vi har valt tre olika tillvägagångssätt baserat på komplexiteten av indata. Dessa tillvägagångssätt implementerades och jämfördes med CGAL [1], ett tredjepartsbibliotek som tillhandahåller lösare av många beräkningsgeometriska problem. Vår lösning klarar problem av en högre grad av komplexitet än tredjepartsbiblioteket vi jämför med. För indata av lägre komplexitetsnivåer löser vi problemet mer effektivt.

El reuso de cama es una práctica cada vez mas frecuente principalmente por razones económicas. El presente estudio tuvo como finalidad evaluar el rendimiento productivo y la calidad sanitaria de pollos de carne criados en cama nueva y cama reusada, para lo cual se criaron 250 pollos machos de la línea Ross 308, 125 en cama nueva y 125 en cama reutilizada por cinco campañas. Semanalmente se obtuvo datos de parámetros productivos, nivel de amoniaco, recuento de ooquistes por gramo de cama, recuento de UFC/g de cama de coliformes, mesófilos y hongos en ambos grupos. Además se evaluó el nivel de anticuerpos mediante ELISA, para las enfermedades de Bronquitis infecciosa (BI), Newcastle (NC), Gumboro (IBD), Anemia infecciosa (AI) y Reovirus (REO) al inicio y al final de la crianza (día 49). Los pollos criados en cama nueva obtuvieron 2.07 de índice de conversión alimenticia y 3.92+0.07kg de peso comparado con 2.09 y 3.87+0.06kg de las aves de cama reusada. Al final del estudio no hubo diferencia estadísticamente significativa (P es menor que 0.05) en relación a los parámetros productivos para ambos grupos. Los niveles de amoniaco y recuento de ooquistes fueron mayores las primeras semanas en cama reusada, sin embargo no hubo diferencia estadística significativa. Solo se encontró estadísticamente significativo el recuento de UFC/g de mesófilos siendo mayor en cama nueva. Los resultados de serología no mostraron seroconversión contra los virus en estudio. Se esperaría que cama proveniente de crianzas sin historia de problemas infecciosos, y con un correcto manejo de las condiciones medio ambientales del galpón, pueda ser reutilizada de una manera segura hasta por cinco campañas.<br>--- The reuse of litter is a common practice in poultry raising due to monetary reasons. The aim of this study was to evaluate the performance and sanitary status of broilers raised in new litter and reused litter. 250 male broilers from the Ross 308 line were raised as follows: 125 in new and 125 in reused litter during 5 flocks. Performance data was collected weekly, as well as ammonia levels, oocysts count per gram of litter, and count of coliformis bacteria, fungi and mesofilic bacteria CFU per gram of litter in both groups. The levels of antibodies against Infectious Bronchitis (BV), Newcastle Disease (ND) Infectious Bursal Disease (IB) Chicken Anemia Virus (CAV) and Avian Reoviruses were evaluated by ELISA test at the beginning and ending of the flock (day 49). The broilers raised in new litter obtained a feed conversion of 2.07 and an average body weight of 3.2±0.07kg, against 2.09 feed conversion and 3.87±0.06kg body weight found in the second group. At the end of the study there was no statistic difference (P is less than 0.05) between the performance parameters for both groups. The ammonia levels and oocyst count were higher during the first weeks in the reused litter group, nevertheless, there was no statistic difference. The CFU count for mesofilic bacteria was higher in the new litter group, being statistically significant. The serology results didn’t show any seroconversion to the virus tested. Upon this, it will be expected that the litter coming from poultry farms without a history of infectious problems and with an adequate handling of environmental conditions of the farm can be safely reused for up to 5 flocks.<br>Tesis

Reconstruction results attempt to rebuild polygons from visibility information. Reconstruction of a general polygon from its visibility graph is still open and only known to be in PSPACE; thus additional information, such as the ordering of the edges around nodes that corresponds to the order of the visibilities around vertices is frequently added. The first section of this thesis extracts, in o(E) time, the Hamiltonian cycle that corresponds to the boundary of the polygon from the polygon's ordered visibility graph. Also, it converts an unordered visibility graph and Hamiltonian cycle to the ordered visibility graph for that polygon in O(E) time. The secod, and major result is an algorithm to reconstruct an arthogonal polygon that is consistent with the Hamiltonian cylce and visibility stabs of the sides of an unknown polygon. The algorithm uses O(nlogn) time, assuming there are no collinear sides, and )(n2) time otherwise.<br>vii, 78 leaves ; 28 cm.

Thesis (Ph. D.)--University of Missouri-Columbia, 2008.<br>The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 4, 2009) Vita. Includes bibliographical references.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.<br>Includes bibliographical references (p. 171-173).<br>by Matthew Willard Eldridge.<br>M.S.

Current predictions of pollen levels rely strictly on historical Averages, regardless of environmental factors that might affect the timing of pollen release by different plants. For this thesis, the goal was to develop a statistical model that will accurately forecast pollen levels by correlating those daily counts to atmospheric and meteorological conditions. This project used ARIMA modeling on IBM’s SPSS Statistics 24 of daily pollen count information for multiple allergenic pollens in the Sarasota County, Florida area over a 11-year period. The pollen species in question for this project are oak and cypress trees, grass, and ragweed pollens; and Alternaria and Cladosporium mold spores. The total pollen counts for weeds, grass, trees, and overall total are also included in the 11 years of data. The atmospheric variables used to predict pollen levels are high temperature, low temperature, average temperature, precipitation, humidity, wind direction, and wind speed for daily observations over the 11-year period. Results for these models showed that maximum temperature, precipitation, humidity, and wind direction were the driving predictors behind the pollen counts in Sarasota, Florida. The analysis of the pollination periods also showed that there were phenological changes according to the specific species. The models and phenological changes are specific to the Sarasota, Florida area, and would serve as a framework for studying other pollination regions.

Many problems in Computational Geometry involve a simple polygon P and a family of geometric objects, say sigma, contained in P. For example, if sigma is the family of chords of P then we may want to find the longest chord in P. Alternatively, given a chord of P, we may wish to determine the areas of the two subpolygons of P determined by the chord. Let pi be a polygonal decomposition of a polygon P. We call pi a visibility decomposition with respect to sigma if, for any object g &isin; sigma, we can cover g with o(|P|) of the subpolygons of pi. We investigate the application of visibility decompositions of polygons to solving problems of the forms described. Any visibility decomposition pi of a polygon P that we construct will have the property that, for some class of polygons &weierp; where the polygons in &weierp; have useful properties, pi &sube; &weierp;. Furthermore, the properties of &weierp; will be key to solving any problems we solve on P using pi. Some of the visibility decomposition classes we investigate are already known in the literature, for example weakly edge visible polygon decompositions. We make improvements relating to these decomposition classes and in some cases we also find new applications for them. We also develop several new polygon visibility decomposition classes. We then use these decomposition classes to solve a number of problems on polygons including the circular ray shooting problem and the largest axis-aligned rectangle problem. It is noteworthy that the solutions to problems that we provide are usually more efficient and always simpler than alternative solutions.

Reducing the number of vertices in a mesh is a problem that if solved correctly can save the user a lot of time in the entire process of handling the model. Most of the solutions today are focused on reducing the mesh in one big step by running a separate application. The goal of this implementation is to bring the reduction application into the users workspace as a plugin. Many of the modellers in the various computer graphics industries use Autodesk Maya the plugins intention is to create a efficient tool which also give the modellers as much freedom as possible without the need to ever leave Mayas workspace. During the process the possible issues and solutions of creating this tool in Maya will also examined to help introduce the process of creating a tool for Maya. This plugin has the potential to improve on the existing reduction tool in Maya by giving the user more options and a more exact solution.

When the National Weather Service (NWS) issues a tornado warning, the alert is rapidly and widely disseminated to individuals in the general area of the warning. Historically, the assumption has been that a false-negative warning perception (i.e., when someone located within a warning polygon does not believe they have received a tornado warning) carries a higher cost than a false-positive warning perception (i.e., when someone located outside the warning area believes they have received a warning). While many studies investigate tornado warning false alarms (i.e., when the NWS issues a tornado warning, but a tornado does not actually occur), less work focuses on studying individuals outside of the warning polygon bounds who believe they received a warning (i.e., false-positive perceptions). This work attempts to quantify the occurrence of false-positive perceptions and possible factors associated with the rate of occurrence. Following two separate storm events, Oklahomans were asked whether they perceived a tornado warning. Their geolocated responses were then compared to issued warning polygons. Individuals closer to tornado warnings or within a different type of warning (e.g., a severe thunderstorm warning) are more likely to report a false-positive perception than those farther away or outside of other hazard warnings. Further work is needed to understand the rate of false-positive perceptions across different hazards and how this may influence warning response and trust in the National Weather Service.

Ingeniero Civil Eléctrico<br>En las plantas faenadoras de pollos se busca sacar el máximo provecho a cada animal, por lo que no solo se comercializan sus partes altas en carne como lo son la pechuga y el trutro, sino que también se venden partes como alas, interiores y patas. El presente trabajo trata de la categorización de patas, ya que no todas tienen el mismo precio, sino que se dividen en categorías dependiendo de su peso y cantidad de defectos, siendo las más grandes y sanas las mejor valoradas. Actualmente, la categorización de patas de pollo se hace de forma manual, lo cual puede estar sujeto a la subjetividad de cada operador, toma bastante tiempo y, a su vez, se refleja en el balance de las empresas como un alto costo fijo por mano de obra. Dado lo anterior, se vuelve muy interesante la automatización de procesos que permitan aumentar su eficiencia en la separación por categorías. En la industria del pollo, las patas del animal son conocidas como garras y sus categorías son llamadas calibres, los que dependen del peso y cantidad de defectos de cada garra. En este trabajo de título se proponen y comparan distintas metodologías para definir el calibre de una garra a partir de dos imágenes, mostrando su parte superior e inferior. Debido a la complejidad del problema, solo se consideran garras sin fracturas o raspaduras, limitando la clasificación a garras con defectos reconocibles por su color como lo son las cutículas, callos y hematomas. Tras probar distintos métodos para clasificar las garras según sus calibres, se llega a uno que consiste en una cuantificación de defectos utilizada como entrada para un clasificador en base a rangos, el cual, con un 97.4% de exactitud, demostró ser el mejor método para definir el calibre. La cuantificación mencionada consiste en utilizar una cascada de clasificadores binarios, con las intensidades RGB de los pixeles como entrada, identificando aquellos que muestran cutícula, callo, hematoma o garra sana, para finalmente obtener la cuantificación con la suma de pixeles de cada defecto. Como conclusión se puede decir que, a pesar de las limitaciones impuestas para el desarrollo de la metodología propuesta, se han logrado los objetivos planteados en forma satisfactoria, logrando obtener un método de clasificación de garras, escalable a la industria faenadora de pollos.

Problemstellung, Forschungsfrage, Ziel und Aufbau der Dissertation In den Altbaugebieten mit Wohnsubstanz in polnischen Städten, welche im zweiten Weltkrieg nicht zerstört wurden, herrschen oft städtebauliche Missstände. Obwohl oft zentral gelegen und mit denkmalgeschützter Substanz bebaut, werden diese Gebiete aufgrund des baulichen, sozialen, wirtschaftlichen und des Umweltzustandes als Problemgebiete bezeichnet. Deren Revitalisierung ist jedoch von wesentlicher Bedeutung für die Entwicklung der Gesamtstadt und für die städtischen Akteure. Revitalisierungsprozesse können nur auf lokaler Ebene angestoßen und durchgeführt werden. Die Gemeinde als lokale Selbstverwaltung ist dabei ein Schlüsselakteur. Allerdings spielen dabei die Gesetzeslage und sonstige Rahmenbedingungen eine wesentliche Rolle. Vor diesem Hintergrund suchte die Dissertation Antworten auf folgende Forschungsfrage: Welche Spielräume und Einschränkungen für die Handlungen polnischer kommunaler Selbstverwaltungen im Bereich der Revitalisierung städtischer Problemgebiete mit Altbausubstanz resultieren aus dem institionellen Kontext? Unter dem institutionellen Kontext werden nach Ansatz des akteurzentrierten Institutionalismus sowohl formelle, rechtliche Regeln als auch informelle Regeln verstanden. Die Forschungsfrage wurde durch folgende Teilfragen präzisiert: □ Welche Handlungsmöglichkeiten und Instrumente werden den Kommunalverwaltungen bei der Gestaltung und Umsetzung der Revitalisierungsprozesse vom polnischen Raumplanungssystem gegeben? □ Welche Handlungsmöglichkeiten und Instrumente werden durch die polnischen kommunalen Selbstverwaltungen in den Prozessen der Revitalisierung genutzt? □ Welche Hindernisse bei der Revitalisierung in den Problemgebieten mit Altbausubstanz in Polen resultieren aus dem institutionellen Kontext? Ziel der Arbeit war die Erläuterung der Möglichkeiten kommunaler Selbstverwaltungen, Prozesse zur Revitalisierung der Alt¬bau¬sub¬stanz in den polnischen Städten im Hinblick auf den institutionellen Kontext zu beeinflussen und zu steuern. Die Arbeit wurde in 7 Kapitel aufgeteilt. Kapitel 1 stellt das Problem und die Forschungsfrage vor und erklärt die wichtigsten Begriffe. Im Kapitel 2 wurden theoretische Grundlagen der Arbeit diskutiert. Das Ergebnis dieses Kapitels bildet das theoretische Fundament für weitere Analysen und die empirische Untersuchung. Im Kapitel 3 wurden die rechtlichen Rahmenbedingungen für Revitalisierung in Polen analysiert. Im Kapitel 4 wurden die angewendeten Methoden und das Design der empirischen Untersuchung beschrieben. Kapitel 5 beschäftigt sich mit der empirischen Fallstudie in Stettin, durch welche anhand der Analyse tatsächlicher Entwicklungen im Revitalisierungsprozess die Ergebnisse des Kapitels 3 eine neue Dimension und Konkretisierung erhalten. In diesem Kapitel wurden auch die informellen Regeln beschrieben, die einen wesentlichen Einfluss auf die Revitalisierungsprozesse haben. Die Ergebnisse und Schlussfolgerungen aus allen Analysen und empirischen Untersuchungen wurden im Kapitel 6 vorgestellt. Die Arbeit schließt mit Empfehlungen für die nationale Ebene bezüglich der Änderungen in den Vorschriften und für die lokale Ebene bezüglich der Gestaltung der Revitalisierungsprozesse in Kapitel 7 ab. Theoretische Grundlagen für die Analyse der Revitalisierungsprozesse Auf der Grundlage der Theorien zum Verfall der städtischen Gebiete und der Ansätze zur Vorbereitung und Durchführung der Revitalisierungsprozesse, welche anhand der Erfahrungen westeuropäischer Länder entwickelt wurden, konnten folgende fünf Schwer¬punkte zur Analyse der rechtlichen Rahmenbedingungen für die Revitalisierungsprozesse in Polen identifiziert werden: □ Ideelle und finanzielle nationale Unterstützung der Revitalisierung als wesentlicher Erfolgs- oder Hemmnissfaktor der Aufwertungsprozesse, □ Suburbanisierung als negativer Faktor in den Verfallsprozessen des Altbaubestandes und als Gefahr für die Revitalisierungsprozesse, □ Beteiligung der Bürger und anderer Akteure an den Revitalisierungsprozessen als ein Beitrag zur Verbesserung der Qualität, der Legitimierung, der Akzeptanz und der erfolgreichen Umsetzung der Revitalisierungsprozesse, □ Integrierte und strategische Planung als eine Erfolgsbedingung der Revitalisierung mit Berücksichtigung der sozialen, ökonomischen, baulichen und ökologischen Faktoren, □ Sanierungen der Wohnsubstanz als ein wesentliches Element der Revitalisierungs¬prozese, welche teilweise von lokalen Bewohnern realisiert werden und die über die Art der Gebietsaufwertung entscheiden. Der Ansatz des akteurzentrierten Institutionalismus diente als theoretische Strukturierung der empirischen Untersuchung. Die empirische Untersuchung liefert eine Begründung für die Handlungen der lokalen Verwaltung durch die Analyse der: □ in die Revitalisierungsprozesse eingebundenen Akteure, deren Fähigkeiten und Handlungs-orientierungen, □ Akteurskonstellationen und Interaktionsformen, □ nicht-institutionellen Rahmenbedingungen, die aus der lokalen Situation resultieren, □ zustande gekommenen Entscheidungen. Rechtliche Rahmenbedingungen für die Revitalisierung in Polen Mit der Revitalisierung sind die Gemeinden in Polen indirekt beauftragt durch die Pflicht, alle öffentlichen Angelegenheiten mit lokaler Bedeutung zu regeln. Dafür haben sie eine absolute planerische Souveränität und das Recht zur Selbstbestimmung ihrer Politiken oder Entwicklungsstrategien zugesprochen bekommen. Die Begrenzungen dieser Planungsmacht erfolgen nicht durch übergeordnete Planung, sondern durch allgemeine Instrumente zur Durchführung der räumlichen Politik. Die Gemeinden haben keine Instrumente zur Verfügung, welche dem Umgang mit dem bebauten Raum dienen. Darüber hinaus haben auf die Revitalisierungsprozesse, neben den Vorschriften des Raumplanungssystems, auch andere Vorschriften, wie jene über das Wohnungswesen, die öffentlichen Finanzen oder öffentlich-private Partnerschaften einen wesentlichen Einfluss. Die EU-Förderrichtlinien sind, aufgrund fehlender nationaler Programme zur Revitalisierung, entscheidend bei der Bestimmung und Struktur der Revitalisierungshandlungen in den polnischen Gemeinden. Informelle Regeln als weitere Faktoren der Nutzung des Handlungsspielraums In der Fallstudie wurden die Spielräume und Hemmnisse für Revitalisierungsprozesse der Altbausubstanz, welche aus dem gesetzlichen Rahmen resultieren, anhand von reellen Beispielen in Stettin (Szczecin) überprüft. Die Analyse der Revitalisierungsprozesse in den Jahren 1989-2008 ergab einen zusätzlichen Einfluss der informellen Regeln, welche zu Konflikten bei den Revitalisierungsprozessen und zur Blockade oder Verlangsamung dieser führen. Schlussfolgerungen: Handlungsspielraum lokaler Selbstverwaltungen bei der Revitalisierung und seine Nutzung Der Handlungsspielraum lokaler Verwaltungen bei der Gestaltung und Durchführung der Revitalisierungsprozesse ist gesetzlich breit definiert. Nur die Entscheidungen der Gemeinde sind bindend für die nicht-öffentlichen lokalen Subjekte. Die Gemeinden dürfen ihre lokalen Politiken eigenständig und souverän bestimmen. Die Vorschriften des Raumplanungs¬systems tragen jedoch nicht zur integrierten und strategischen räumlichen Planung der Gemeinde bei. Die Bestimmungen dieser Gesetze haben überwiegend zum Ziel, Investitionen in den Neubau zu erleichtern und haben den Umgang mit bebautem Raum nicht zum Gegenstand. Es gibt auch keine speziellen Instrumente, rechtliche Lösungen oder nationale Programme, welche die Revitalisierung oder den Stadtumbau zum Gegenstand haben. Die vorhandenen Programme wie der Nationale Wohnungsfonds oder der Thermoisolationsfonds beziehen sich auf ausgewählte physische Aspekte der Revitalisierung und haben keinen strategischen oder integrierten Charakter. Die lokalen Verwaltungen haben einen beschränkten Einfluss auf die Höhe ihrer Einnahmen. Aufgrund der vielen Aufgaben, mit denen sie betraut sind und der dabei geringen Ausstattung mit finanziellen Mitteln für deren Erfüllung, haben sie grundsätzlich einen engen finanziellen Spielraum. Die Vorschriften für Zuwendungen aus dem Nationalen Wohnungs¬fonds bestimmen, welche Aufgaben durch welche öffentlichen Subjekte zuschussfähig sind. Somit beeinflussen diese die Verteilung der Aufgaben zwischen verschiedenen Subjekten und auch die Entstehung dieser Subjekte mit, wie das bei den verschiedenen kommunalen Gesellschaften der Fall ist. Die Vorschriften des Wohnungswesens wiederum schützen überwiegend die Interessen der Mieter und durch die bis 2007 gültigen Beschränkungen der Miethöhe, auch in privaten Beständen, beeinflussten sie wesentlich die Investitions¬bereitschaft der Besitzer und somit die Länge und das Ausmaß der Sanierungsprozesse. Aufwendige und kostspielige Prozeduren bei der Vertragsgestaltung der öffentlich-privaten Partnerschaften haben zur Folge, dass es bis heute so gut wie keine solchen Partnerschaften bei den Revitalisierungsmaßnahmen gibt. Da die lokalen Verwaltungen praktisch weder finanzielle noch ideelle Unterstützung von der nationalen Ebene bei der Führung ihrer Raumpolitik erhalten, sind sie bei der Revitalisierung auf eigene Ideen und Eigenfinanzierung, auf private Investitionen und Finanzierung aus verschiedenen europäischen Programmen angewiesen. Die Förderung vom Integrierten operationellen Programm der Regionalentwicklung 2004-2006 führte zur Entstehung vieler Initiativen in Form von Revitalisierungsprogrammen. Auf die Abschöpfung dieser Mittel ist auch die nationale Politik eingestellt, wo die meisten Dokumente mit Bezug zur Raumplanung vor dem Hintergrund der EU-Finanzierung erstellt wurden. Bei der Nutzung der Handlungsmöglichkeiten durch die lokale Verwaltung in Stettin dominieren die direkten Instrumente und direkte Einflussnahme auf die Revitalisierungs¬prozesse, wie kommunale Investitionen in die technische und soziale Infrastruktur, die Bildung von kommunalen Gesellschaften zur Sanierung oder Revitalisierung der Bestände. Die indirekten Handlungen dienen überwiegend der Gewinnung von EU-Fördermitteln und dem Anreiz für Investitionen nicht-öffentlicher Subjekte. Es handelt sich hierbei überwiegend um Strategien zur lokalen Entwicklung oder Revitalisierung. Die strukturierende Handlungs¬weise ist erst im Entstehen und wird wesentlich von der Politik-Umwelt und von informellen Regeln geprägt. Zur Einschränkung der Nutzung des gegebenen Handlungsspielraumes tragen, neben den gesetzlichen Bestimmungen auch die in der Fallstudie identifizierten informellen Regeln bei. Es wurden drei Regeln identifiziert, die einen Einfluss auf die Revitalisierungsprozesse haben: 1. die Bestandswahrung der Bewohner, 2. das Misstrauen der Bewohner der lokalen Verwaltung gegenüber und 3. das niedrige Image der Bewohner vernachlässigter Gebiete bei den Vertretern der Stadtverwaltung. Die Bestandswahrung eines Teils der Bewohner bezieht sich auf die Wahrung von Privilegien wie niedrige Mieten, große Wohnungen praktisch ohne Kündigungsgefahr, Pseudoeigentumsrechte und vor allem die Abdeckung der Instandhaltungskosten der Wohnungen und Häuser durch die Gemeinde. Diese Bestands¬wahrung führt zu Forderungspositionen eines Teils der Bewohner, zu Protesten gegen die Sanierungsmaßnahmen, die mit Umzügen oder Erhöhung der Mieten verbunden sind und zur fehlenden Bereitschaft der Wohnungsbesitzer, die Sanierungen in den ehemals kommuna¬len Wohnungen, welche an die bisherigen Bewohner verkauft wurden, ganz oder anteilig zu finanzieren. Wiederum führt das mangelnde Vertrauen gegenüber der Stadt¬verwaltung und gleichzeitig das schlechte Image der Bewohner von Problemgebieten bei den Vertretern der Stadtverwaltung zu einer niedrigen Bereitschaft der Vertreter der Verwaltung, mit den Bewohnern zu sprechen oder mit ihnen zu kooperieren und in der Konsequenz zu Konflikten und teilweise zur Blockade der Vorhaben. Vorschläge zur Änderung der Vorschriften Die eigenen Vorschläge der Autorin zur Änderung der Vorschriften, welche einen Einfluss auf die Revitalisierungsprozesse in Polen haben, ergänzen die Diskussion, welche in der polnischen Fachliteratur geführt wird. So sind in erster Linie Änderungen notwendig, welche die faktische Handlungsfähigkeit der Gemeinde innerhalb des bestehenden Raum¬planungs¬systems sichern würden, wie die Stärkung der Rolle der obligatorischen und gemeinde¬übergreifenden „Studie der Rahmenbedingungen und Richtlinien der Raumbewirtschaftung“ oder die Beschränkung der Erstellungskosten der fakultativen lokalen Pläne räumlicher Bewirtschaftung. Des Weiteren ist die Präzisierung und der Ausbau der Vorgänge zur Akteur¬partizipation an den Planungsprozessen bei der Revitalisierung notwendig. Die Einführung des lokalen Revitalisierungsprogrammes als ein gesetzlich definiertes Instrument, welches der Integration der Politiken und einer strategischen Ausrichtung der Handlungen der Gemeinde im Bereich der Revitalisierung dienen soll, wird nach den Ergebnissen der Arbeit, als eine Voraussetzung für erfolgreiche Revitalisierungsprozesse gesehen. Darüber hinaus sind Änderungen in anderen als den direkt mit dem Raumplanungssystem verbundenen Vorschriften, wie z. B. in den Gesetzen zum Wohnungswesen, der öffentlichen Finanzen oder öffentlich-privaten Partnerschaften erforderlich. Notwendig für die Revitalisierung ist auch die ideelle und finanzielle Unterstützung durch die nationale Ebene in Form von Leitlinien, Steuervergünstigungen oder Programmen. Diese sollen das gewünschte städtebauliche Modell der räumlichen Entwicklung darstellen und fördern sowie die aktive Einbindung aller öffentlichen und nicht-öffentlichen Akteure in die Revitalisierungsprozesse unterstützen. Verbesserungsvorschläge für die Revitalisierungsprozesse in Stettin Im theoretischen Exkurs wurde die städtische Regimetheorie für die Abschätzung der zukünftigen Entwicklung und die Formulierung der Empfehlungen für die Verbesserung der Revitalisierungsprozesse in Stettin angewandt. Eine Entstehung eines neuen Regimes ist nur dann möglich, wenn das alte Regime von den Wählern nicht mehr für legitim gehalten wird oder wenn in der Stadt eine Koalition entsteht, die einen Meinungswechsel der Bewohner herbeiführt. Für die Revitalisierung, die nur im symbolischen Regime erfolgreich möglich ist, ist auch das gegenseitige Vertrauen der Akteure eine Grundvoraussetzung für den Erfolg. Das Vertrauen der nicht-öffentlichen Akteure kann u. a. durch Planungssicherheit und Unabhängigkeit der kommunalen Vorhaben von den Legislaturperioden erlangt werden. Diese können wiederum im gegenwärtigen polnischen Raumplanungssystem durch eine hohe Abdeckung mit lokalen Plänen räumlicher Bewirtschaftung als kommunale Rechtsakte erreicht werden. Zusätzlich könnte eine mit den Akteuren gemeinsam vorbereitete und abgestimmte Stadtentwicklungsstrategie und darauf basierende Politiken diese Sicherheit und Unabhängigkeit stärken. Als Anstoß der Zusammenarbeit wird eine mehrtägige Veranstaltung „Stadt-Tage“ vorgeschlagen, an der sowohl das Fachpublikum als auch die Bewohner Stettins teilnehmen und die aus Ausstellungen, Konferenz, Werkstätten und Wettbewerben bestehen sollte. Der Nutzen dieser Veranstaltung läge vor allem in der Stärkung des Themas der Revitalisierung gegenüber anderen Themen im Stadtrat und der Möglichkeit der Einbringung eigener Ideen der Akteure in die Stettiner Stadtentwicklung.

Mit großer Skepsis werden in Polen die Diskussionen zum Thema "Kerneuropa" aufgenommen. Das Land fürchtet, an den Rand gedrängt zu werden, sollte ein innerer Kreis in der EU, eine "Union in der Union", entstehen. Deutschland hat mehrfach die Idee eines Kerneuropa unterstützt. Ein deutsch-polnischer Austausch zu Inhalten und Perspektiven eines solchen Kerns könnte darum polnische Befürchtungen abbauen.<br>Poland is skeptical about the idea of a "core Europe". The country fears to get relegated to the fringes of European integration if an inner circle of the EU, a "Union in the Union", was to emerge. By starting a bilateral dialogue on the content and the perspectives of a "core Europe", Germany – which at various occasions has supported the idea of a core Europe – might be able to reduce Polish fears.

La fertilité du pollen de mil (Pennisetum typhoïdes) a été étudiée à l’état frais et après conservation. Plusieurs tests de fertilité ont été utilisés : le colorant d’ALEXANDER, la coloration au diacétate de fluorescéine, la germination in vivo et le taux de grenaison. A l’exception du premier, les corrélations entre les tests pris deux à deux sont positives et très hautement significatives. Le pollen de mil reste fertile environ 12 jours en conditions ambiantes. De nombreux échantillons ont été stockés à 3-5°C et 26-30%, 52-56% ou 70-75% d’humidité relative. En stockage, la fertilité du pollen peut persister pendant plus d’un an au mieux. La fertilité du pollen peut persister pendant plus d’un an au mieux. La fertilité pollinique est influencée par le génotype et les conditions de croissance de la plante émettrice du pollen, par la méthode de récolte, et par l’hygrométrie de stockage. Les mécanismes de la mort du pollen ont été étudiés d’après les courbes de mortalité pollinique et comparaisons entre les résultats de différents tests de fertilité. L’utilité de la conservation de la fertilité du pollen pour l’amélioration des plantes et pour la gestion des ressources génétiques est discutée<br>The fertility of the pollen of pearl millet (Pennisetum typhoïdes) was studied fresh and after conservation. Several pollen fertility tests were used: Alexander’s stain, fluorescein diacétate staining, in vivo germination and seed set. Except for the first of these tests, the correlation between pairs of tests was positive and very highly significant. Pearl millet pollen stayed fertile for about 12 days in ambient conditions. Many pollen samples were stored at 3-5°C in 26-30%, 25-56% or 70-75% relative humidity. In storage, at best, pollen fertility persisted for over a year. Pollen fertility was influenced by genotype and the growth conditions of the pollen source plants, by harvesting methods, and by storage hygrometry. The mechanisms underlying pollen mortality were studied by examining death curves and by comparing the results of different fertility tests. The usefulness of the conservation of pollen fertility is discussed in relation to plant improvement and genetic resources management

Made available in DSpace on 2014-12-17T14:07:14Z (GMT). No. of bitstreams: 1 TharsiaCCC_TESE.pdf: 4165596 bytes, checksum: b73b464d52ff23430b153992ec45405a (MD5) Previous issue date: 2013-04-25<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior<br>This work aims at obtaining nanoparticles of iron oxide, the magnetite one (Fe3O4), via synthesis by thermal decomposition through polyol. Thus, two routes were evaluated: a simple decomposition route assisted by reflux and a hydrothermal route both without synthetic air atmosphere using a synthesis temperature of 260?C. In this work observed the influence of the observe of surfactants which are generally applied in the synthesis of iron oxide nanoparticles decreasing cluster areas. Further, was observed pure magnetite phase without secondary phases generally found in the iron oxide synthesis, a better control of crystallite size, morphology, crystal structure and magnetic behavior. Finally, the introduction of hydroxyl groups on the nanoparticles surface was analyzed besides its employment in the polymer production with OH radicals. The obtained materials were characterized by XRD, DLS, VSM, TEM, TG and DSC analyses. The results for the magnetite obtainment with a particle size greater than 5 nm and smaller than 11 nm, well defined morphology and good magnetic properties with superparamagnetic behavior. The reflux synthesis was more efficient in the deposition of the hydroxyl groups on the nanoparticles surface<br>O objetivo desse trabalho foi a obten??o de nanopart?culas de ?xido de ferro, a magnetita (Fe3O4), via s?ntese por decomposi??o t?rmica via poliol, avaliando assim duas rotas: a rota simples decomposi??o assistida por refluxo e a rota hidrot?rmica, ambas sem atmosfera de ar sint?tico e usando a temperatura de s?ntese de 260?C. Observou-se nesse trabalho a influ?ncia da aus?ncia de surfactantes, comumente utilizados em s?nteses de ?xidos de ferro, com a finalidade de promover uma melhor dispers?o das nanopart?culas, diminuindo assim as ?reas de aglomerados. Al?m disso, visou-se: a obten??o de uma fase puramente de magnetita, sem a forma??o de fases secund?rias comumente encontradas nas s?nteses dos ?xidos de ferro; um melhor controle do tamanho de cristalito; da morfologia; da estrutura cristalina e do comportamento magn?tico. Por fim, analisou-se a introdu??o dos grupos hidroxilas na superf?cie das nanopart?culas, e sua empregabilidade na produ??o de pol?meros com radicais (OH). Os materiais obtidos foram caracterizados por an?lises de DRX, DLS, VSM, TEM, TG e DSC. Os resultados foram satisfat?rios quanto ? obten??o da magnetita, com tamanho de part?cula maior que 5 nm e menor que 11 nm, de morfologia bem definida e com boas propriedades magn?ticas com comportamento superparamagn?tico. Quanto ? deposi??o dos grupos de hidroxilas na superf?cie das nanopart?culas, a s?ntese com refluxo mostrou-se mais eficiente

Co-flowering plants within communities typically share pollinators which can lead to the deposition of pollen grains from varying species onto stigmas; or heterospecific pollen transfer (HPT). It has been shown that HPT can have varying effects on plant reproductive success. These effects can range from an 80% reduction on seed production to no effect. However, to date, there are no studies that have evaluated the causes underlying variability of these effects. We investigated this variability through a greenhouse experiment. Hand-pollinations were conducted with a mix of conspecific and heterospecific pollen and a control (conspecific pollen only). We used six pollen recipient and four species as donors for the heterospecific pollen (5 treatments total) We conducted hand-pollinations on a minimum of 10 plants per species (584 total pollinations). After pollination seed set data was recorded for each treatment and the amount of conspecific and heterospecific pollen on stigmas was recorded. We evaluated if the effects of HPT can be explained by the recipient species, the donor species or the interaction between donor and recipient. The results show high variability in the magnitude of HPT(2-93) but this variability is not a result of donor characteristics or even recipient characteristics but a result of the interactions between donors and recipients (df=20, α=.05, p=0.015). We will further investigate if the interaction can be explained by stigma/pollen size ratio, degree of co-flowering, or phylogenetic distance between donor and recipient species. This study will contribute to advance our understanding of how co-flowering plant communities interact amongst themselves after pollination.

Los polos de algodón son uno de los principales productos con mayor exportación del sector textil debido a la calidad de su confección y fino acabado. El Perú, desde el 2009, cuenta con un acuerdo promocional comercial con EE.UU., principal importador de polos de algodón peruano, sin embargo las exportaciones a dicho destino no han tenido el crecimiento esperado. Por lo cual, la presente investigación tiene la finalidad de identificar si las reglas de origen negociadas en el APC Perú- EE.UU. son un condicionante en la competitividad de las exportaciones de polos de algodón, considerando el periodo de 10 años desde la entrada en vigencia de dicho acuerdo. Para llevar a cabo la investigación, se ha revisado los antecedentes históricos previos al APC, las reglas de origen y las reglas específicas, para tener un mejor panorama de la situación del problema, asimismo se realizó un análisis situacional global, regional y nacional. La presente es una investigación con enfoque cualitativo que recolecta los datos de forma primaria directamente de los principales actores de las exportaciones de polos de algodón hacia EE.UU., mediante entrevistas, de las cuales se obtuvo como resultado que si bien es cierto que las reglas de origen establecidas en el APC Perú – EE.UU., exigen el uso de hilado originario de una de las partes de los países miembros, y de cierta manera condiciona la competitividad, sin embargo es un punto que los exportadores pueden y han venido manejando desde antes de la entrada en vigencia del APC.<br>T- shirts cotton are one of the main products of the textiles market due to the quality of their clothing and use of fine raw materials Since 2009, Peru has had a commercial promotional agreement with the United States, the main importer of Peruvian t-shirts cotton, however, exports to that destination have not had the expected growth. Therefore, this research aims to identify whether the rules of origin negotiated in the Peru-US APC are a determining factor in the competitiveness to exports of t-shirts cotton, considering the 10-year period from entry into force mentioned agreement to carry out the research, the historical antecedents prior to the APC, the rules of origin and the specific rules have been reviewed to have a better overview of the problem situation, as well as a global, regional and national situational analysis. This is a research with a qualitative approach that collects data primarily directly from the main exporter of t-shirts cotton to the United States, through interviews, from which it was obtained as a result that the rules of origin established in the APC Peru - USA, require the use of yarn originating from one of the parts of the member countries, and in a certain way conditions competitiveness, however it is a point that exporters have already been considering since before entry into force of the APC.<br>Tesis

Le pollen des Graminées est l'un des principaux vecteurs d'allergènes. Il contribue à l'apparition des allergies respiratoires comme l'asthme et la rhinite allergique. En contact avec l'eau de pluie ou des polluants atmosphériques, le pollen peut libérer des microparticules (<5 !m) dites granules cytoplasmiques de pollen. À cause de leur taille, ces granules peuvent pénétrer plus profondément dans l'appareil respiratoire que le pollen entier et induire ainsi des réactions allergiques. L'objectif de ce travail est de caractériser l'allergénicité de ces granules selon 3 volets : épidémiologique, expérimental et analytique. Les résultats de l'étude épidémiologique mettent évidence un effet éventuel des granules dans la survenue des allergies respiratoires, et plus particulièrement de l'asthme. Dans la partie expérimentale, les résultats obtenus permettent de montrer que les granules induisent des réactions allergiques, humorales et cellulaires ainsi que des réponses inflammatoires, comparables au pollen entier, chez le rat Brown Norway, le modèle animal d'allergie ici utilisé. Enfin, la partie analytique permet de conclure que l'allergénicité des granules dépend à la fois de leur contenu en allergènes hydrosolubles et non-hydrosolubles.

Many condensed matter problems involve a particle coupled to its environment. The polaron, originally introduced to describe electrons in a polarizable medium, describes a particle coupled to a bosonic field. The Holstein polaron model, although simple, including only optical Einstein phonons and an interaction that couples them to the electron density, captures almost all of the standard polaronic properties. We herein investigate polarons that differ significantly from this behaviour. We study a model with phonon-modulated hopping, and find a radically different behaviour at strong couplings. We report a sharp transition, not a crossover, with a diverging effective mass at the critical coupling. We also look at a model with acoustic phonons, away from the perturbative limit, and again discover unusual polaron properties. Our work relies on the Bold Diagrammatic Monte Carlo (BDMC) method, which samples Feynman diagrammatic expansions efficiently, even those with weak sign problems. Proposed by Prokof'ev and Svistunov, it is extended to lattice polarons for the first time here. We also use the Momentum Average (MA) approximation, an analytical method proposed by Berciu, and find an excellent agreement with the BDMC results. A novel MA approximation able to treat dispersive phonons is also presented, along with a new exact solution for finite systems, inspired by the same formalism.

OBJETIVO: Se ha estudiado el comportamiento cinético de atorvastatina en pollos tras la administración por las vías intravenosa y oral de una dosis de 3 mg/kg de este fármaco hipolipemiante, con el fin de validar la dosis a utilizar en el biomodelo animal utilizado. MÉTODOS: La determinación de atorvastatina en plasma se realizó mediante HPLC con detección ultravioleta, siguiendo el método descrito por Siefert (1999), modificado para atorvastatina. El ajuste a métodos farmacocinéticos compartimentales y no compartimentales se realizó mediante el programa WinNonlin Professional®. El criterio utilizado para determinar cuál era la ecuación que mejor describía la evolución de los datos experimentales en cada caso, fue el Criterio de Información de Akaike (AIC) (Yamaoka et al., 1978). RESULTADOS: Tras la administración intravenosa, atorvastatina se distribuye según un modelo bicompartimental abierto, a diferencia del modelo monocompartimental descrito para la vía oral. Tras la administración intravenosa, la vida media obtenida para el atorvastatina (t1/2λz) fue de 4,85 h con un tiempo medio de residencia (MRT) de 10,69 h. Los volúmenes aparentes de distribución calculados en función del área bajo la curva (Vz) y en estado estacionario (Vss) resultaron ser de 0,60 L/kg y 0,32 L/kg respectivamente, indicando una amplia distribución orgánica. En cuanto al aclaramiento plasmático (Cl), éste alcanzó un valor de 30.99 mL/kg•h. Por vía extravascular, cuando se administró atorvastatina por vía oral, se registraron los siguientes tiempos de vida media: 17,54 h con un valor de MRT de 26,03 horas. CONCLUSIONES: La biodisponibilidad de atorvastatina cuando se administró por vía oral alcanzó un valor de 93.38 %. En el estudio del descenso de los perfiles lipídicos en pollos tratados con atorvastatina, los resultados analíticos de los parámetros lipídicos del plasma en los grupos experimentales dieron como resultado una disminución del 33 % de los niveles de colesterol total en el grupo tratado con atorvastatina respecto al grupo control aterogénico.<br>OBJETIVE: Pharmacokinetics of atorvastatin was studied following intravenous and oral administration of single doses of 3 mg/kg to chickens. METHODS: Plasma concentrations were determined by HPLC assay with ultraviolet detection following the method described by Siefert et al(1999) modified for atorvastatin. The fitting to compartmental and non compartmental pharmacokinetic methods was carried out by using WinNonlin Professional® computer programmes. The Akaike´s information criterion (AIC) (Yamaoka et al., 1978) was used to select the best equation that defines plasma concentration-time data for each animal. RESULTS: The atorvastatin plasma concentration is distributed by a two compartment open model for intravenous dosing, unlike one-compartment model that could best be described for oral administration. The atorvastatin terminal half-life (t½z) was 4.85 h after intravenous administration, with a mean residence time (MRT) of 10.69 h. The apparent volumes of distribution calculated by the area method (Vz) and at steady-state (Vss) were 0.60 and 0,32 L/kg, respectively, indicating a wide body distribution. Total body clearance was 30.99 mL/kg•h. After extravascular administrations, terminal half-lives was 17.54 h. MRT value obtained was 26.03 h. CONCLUSION: Absolute bioavailability was 93.38 % after atorvastatin oral administration. Pharmacokinetic values obtained in this work confirm the validity of the animal model (chickens fed hypercholesterolemic diets to induce atherosclerosis) and make it suitable for atorvastatin intervention studies. The biodisponibility value near to 100% makes it possible to use its own dosage regimen, avoiding extrapolation from human dosage. We can see as well that the values of serum total cholesterol decrease in 33% in the group treated with atorvastatin versus those fed hypercholesterolemic diets.