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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.
1

Characterization of PMN-35PT Thin Film Relaxor Ferroelectric

Keogh, Declan 05 1900 (has links)
High quality epitaxial thin films oflead magnesium niobate -lead titanate (PMN0.35PT) were deposited on MgAh04 substrates in the (001) direction with a lattice mismatch of less than 2%. Characterization by transmission electron microscopy and xray diffraction, has revealed high quality single crystal epitaxial thin films oriented in the (001) direction with a tetragonal unit cell. Capacitance measurements were completed by interdigital dielectrometry and using Finite Element Modeling the dielectric constant for the thin film yielded values ranging from 561 -799 at lk:Hz and 518-746 at 100kHz when the temperature was varied from 273-473K. Additionally, the dielectric maximum has been shifted to higher temperature and the frequency dispersion of the dielectric constant appears to be minimized. Piezoresponse microscopy and transmission electron microscopy was completed on both single and multilayer heterostructures. Transmission electron microscopy shows that the single layer samples show excellent morphology with single crystal epitaxial growth in the (001) direction. In addition piezoresponse microscopy and TEM have elucidated the difficulty in producing high quality films of PMN-0.35PT with a BaNb0.5Ti0.503 bottom electrode. The tendency for columnar growth of BaNb0.5Ti0.503 establishes an environment for polycrystalline growth drastically reducing the probability of single crystal growth in subsequent layers. Finally, piezoresponse microscopy allowed the observation of self polarization in PMN-0.35PT within the polycrystalline films which is in agreement with observations of previous researchers. / Thesis / Master of Applied Science (MASc)
2

Élaboration et caractérisations de films ferroélectriques relaxeurs de PMN-PT : intégration sur silicium et applications MEMS / PMN-PT thin films synthesis and characterization : silicon integration and MEMS applications

Detalle, Mikaël 12 June 2008 (has links)
Par souci de miniaturisation, nous assistons à l'émergence des microsystèmes de type MEMS (voir de type NEMS). L'objectif de ces travaux est d'étudier un matériau actif très prometteur pour ce type d'applications de part ses propriétés électromécaniques exceptionnelles: le PMN-PT. L'élaboration de couches minces de PMN-PT a été optimisée. L'étude montre qu'il est possible de cristalliser le PMN-PT dès 400°C quel que soit le pourcentage de PT, où le type d'électrode (TiOx/Pt et LNO) considéré. Une nucléation dans le volume du film a été mise en évidence et pourrait être à l'origine d'un mécanisme de cristallisation tout à fait atypique. La comparaison des performances diélectriques, ferroélectriques et électromécaniques du PMN-PT déposé sur TiOx/Pt (pulvérisation cathodique) et sur LNO (sol-gel), a permis de mettre en avant une forte dépendance de ces propriétés vis à vis de l'orientation et des interfaces films/électrode, en faveur des films déposés sur LNO. Le caractère relaxeur est d'autant plus présent que la température de recuit des films est optimale. Les dépôts de LNO par pulvérisation cathodique ont engendré un gain important sur les performances du PMN-PT, en particulier grâce à la réalisation d'électrodes supérieures. Ce point marque là aussi toute l'importance du rôle joué par les interfaces inférieures et supérieures dans la réponse globale de la structure électrode/PMN-PT/électrode. / For miniaturization considerations, emergence ofMEMS has been observed. The objective ofthis study is to examine a very promising active material for such applications, with exceptional e1ectromechanica1 properties: PMN-PT. The deve10pment of thin 1ayers of PMN-PT has been optimized. The study shows that it is possible to crystallize PMN-PT at 400 ° C independently of the considered PT percentage or bottom e1ectrode nature (TiOx / Pt and LNO). Volumic nucleation, which could be at the origin of a quite atypical crystallization mechanism, has been highlighted in thin films. The dielectric, ferroe1ectric and electromechanica1 performances comparison of PMN-PT deposited on TiOx / Pt (sputtering) and LNO (solgel), shows a strong dependence of these properties with respect to the orientation and interfaces films / electrode, with an advantage for films deposited on LNO. Relaxor behavior is more and more pronounced as annealing temperature becomes optimal. LNO Sputtering deposition have permit to improve PMN-PT performances, in particular through top electrodes achievement. This underline the importance of the role played by the interfaces in the overall response of the structure e1ectrode / PMN-PT / e1ectrode.
3

Control of Secondary Granule Release in Neutrophils by Ral GTPase

Chen, Xiaojing 07 May 2011 (has links)
Neutrophil (PMN) inflammatory functions, including cell adhesion, diapedesis, and phagocyto-sis, are dependent on the mobilization and release of various intracellular granules/vesicles. In this study, I found that treating PMN with damnacanthal, a Ras family GTPase inhibitor, resulted in a specific release of secondary granules, but not primary or tertiary granules, and caused dy-sregulation of PMN chemotactic transmigration and cell surface protein interactions. Analysis of the activities of Ras members identified Ral GTPase as a key regulator during PMN activation and degranulation. In particular, Ral was active in freshly isolated PMN, while chemoattractant stimulation induced a quick deactivation of Ral that correlated with PMN degranulation. Over-expression of a constitutively active Ral (Ral23V) in PMN inhibited chemoattractant-induced secondary granule release. By subcellular fractionation, I found that Ral, which was associatedwith the plasma membrane under the resting condition, was redistributed to secondary granules after chemoattractant stimulation. Blockage of cell endocytosis appeared to inhibit Ral transloca-tion intracellularly. In conclusion, these results demonstrate that Ral is a critical regulator in PMN that specifically controls secondary granule release during PMN response to chemoattrac-tant stimulation.
4

Influência dos dopantes potássio e lítio na cerâmica relaxora niobato de chumbo e magnésio (PMN)

Cavalheiro, Alberto Adriano [UNESP] 08 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-08Bitstream added on 2014-06-13T20:03:18Z : No. of bitstreams: 1 cavalheiro_aa_dr_araiq.pdf: 6472595 bytes, checksum: e04161cc1c7b719e9fdf747d97469e9f (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho se focaliza na obtenção da cerâmica relaxora PMN com temperatura de máxima constante dielétrica se situando próximo à temperatura ambiente, alta constante dielétrica e valores de perda dielétrica baixos. A influência dos dopantes potássio e lítio durante a síntese dos pós e o processamento da cerâmica PMN constitui uma grande contribuição para a pesquisa deste tipo de material. Os pós de PMN foram sintetizados utilizando a rota da columbita associada ao método de coprecipitação de chumbo. O monitoramento da formação da fase columbita foi acompanhado por DRX. O refinamento de estrutura, o cálculo do tamanho médio de cristalito e a microdeformação de rede foram executadas utilizando o método de Rietveld. Além disso, as amostras foram caracterizadas por TG/DTA, BET e MEV. Diferentemente do lítio, o potássio provoca a elevação da temperatura de formação da fase MgNb2O6 (MN), mas isto não interfere na obtenção do precursor monofásico até a concentração de 2,0%mol de dopante. Para pós de MN calcinados a 900ºC por 2 horas, a presença dos dopantes atenuam a microdeformação de rede e aumentam o tamanho médio de cristalito e, conseqüentemente ocorre a formação de partículas secundárias. Os valores de tamanho médio de cristalito das amostras de PMN dopadas com lítio, calcinadas a 800ºC por 2 horas, são maiores do que para as amostras dopadas com potássio. Nesta condição, a adição de lítio também acarreta crescimento de partículas e aglomeração dos pós. Durante a sinterização, as amostras dopadas com potássio apresentaram tamanho de grão menor e com menor faixa de distribuição de tamanhos, enquanto que para o lítio houve uma menor perda de massa. A mescla de pós permitiu obter maiores valores de densidade a verde, reduzir a perda de massa e obter uma cerâmica mais densa. A adição de,... / This work aims at getting the relaxor ceramic PMN with temperature of maximum dielectric constant close to room temperature, high dielectric constant and low dielectric loss values. The influence of the potassium and lithium additives during powder synthesis and processing of the PMN ceramic constitutes a great contribution to the research of this material type. The PMN powders were synthesized by using the columbite route associated to the lead co-precipitation method. The columbite phase formation was verified by XRD. The structure refinement, calculus of mean crystallite size and lattice microstrain were performed by using the Rietveld method. Furthermore, the samples were characterized by TG/DTA, BET and SEM. Differing from lithium, potassium increases the temperature of MgNb2O6 phase formation, however it does not hinder obtaining the monophasic precursor until 2mol% of additives. For columbite powders, burned at 900ºC during 2 hours, additive presence attenuates the lattice microstrain and increases the mean crystallite size and, consequently, the secondary particle formation occurs. The values of mean size crystallite for lithium doped-PMN samples burned at 800ºC during 2 hours are bigger than potassium ones. In this condition, the lithium doping causes particles growth and powder agglomeration. In sintering, the potassium doped-PMN samples showed smaller grain size and short range of size distribution, while the lithium doped ones showed lesser weight loss. The powder mixture allowed obtaining greater green density values, decreasing weight loss and getting a denser ceramic. Potassium addition reduces Km and Tm values, while the lithium addition, increases these values if compared to PMN. The utilization of LiNbO3 seeds reduces the weight loss and helps the ceramic densification. The seeded sample showed a diffuse phase transition more...(Complete abstract, click electronic access below)
5

Influência dos dopantes potássio e lítio na cerâmica relaxora niobato de chumbo e magnésio (PMN) /

Cavalheiro, Alberto Adriano. January 2002 (has links)
Resumo: Este trabalho se focaliza na obtenção da cerâmica relaxora PMN com temperatura de máxima constante dielétrica se situando próximo à temperatura ambiente, alta constante dielétrica e valores de perda dielétrica baixos. A influência dos dopantes potássio e lítio durante a síntese dos pós e o processamento da cerâmica PMN constitui uma grande contribuição para a pesquisa deste tipo de material. Os pós de PMN foram sintetizados utilizando a rota da columbita associada ao método de coprecipitação de chumbo. O monitoramento da formação da fase columbita foi acompanhado por DRX. O refinamento de estrutura, o cálculo do tamanho médio de cristalito e a microdeformação de rede foram executadas utilizando o método de Rietveld. Além disso, as amostras foram caracterizadas por TG/DTA, BET e MEV. Diferentemente do lítio, o potássio provoca a elevação da temperatura de formação da fase MgNb2O6 (MN), mas isto não interfere na obtenção do precursor monofásico até a concentração de 2,0%mol de dopante. Para pós de MN calcinados a 900ºC por 2 horas, a presença dos dopantes atenuam a microdeformação de rede e aumentam o tamanho médio de cristalito e, conseqüentemente ocorre a formação de partículas secundárias. Os valores de tamanho médio de cristalito das amostras de PMN dopadas com lítio, calcinadas a 800ºC por 2 horas, são maiores do que para as amostras dopadas com potássio. Nesta condição, a adição de lítio também acarreta crescimento de partículas e aglomeração dos pós. Durante a sinterização, as amostras dopadas com potássio apresentaram tamanho de grão menor e com menor faixa de distribuição de tamanhos, enquanto que para o lítio houve uma menor perda de massa. A mescla de pós permitiu obter maiores valores de densidade a verde, reduzir a perda de massa e obter uma cerâmica mais densa. A adição de,...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aims at getting the relaxor ceramic PMN with temperature of maximum dielectric constant close to room temperature, high dielectric constant and low dielectric loss values. The influence of the potassium and lithium additives during powder synthesis and processing of the PMN ceramic constitutes a great contribution to the research of this material type. The PMN powders were synthesized by using the columbite route associated to the lead co-precipitation method. The columbite phase formation was verified by XRD. The structure refinement, calculus of mean crystallite size and lattice microstrain were performed by using the Rietveld method. Furthermore, the samples were characterized by TG/DTA, BET and SEM. Differing from lithium, potassium increases the temperature of MgNb2O6 phase formation, however it does not hinder obtaining the monophasic precursor until 2mol% of additives. For columbite powders, burned at 900ºC during 2 hours, additive presence attenuates the lattice microstrain and increases the mean crystallite size and, consequently, the secondary particle formation occurs. The values of mean size crystallite for lithium doped-PMN samples burned at 800ºC during 2 hours are bigger than potassium ones. In this condition, the lithium doping causes particles growth and powder agglomeration. In sintering, the potassium doped-PMN samples showed smaller grain size and short range of size distribution, while the lithium doped ones showed lesser weight loss. The powder mixture allowed obtaining greater green density values, decreasing weight loss and getting a denser ceramic. Potassium addition reduces Km and Tm values, while the lithium addition, increases these values if compared to PMN. The utilization of LiNbO3 seeds reduces the weight loss and helps the ceramic densification. The seeded sample showed a diffuse phase transition more...(Complete abstract, click electronic access below) / Orientador: Maria Aparecida Zaghete / Coorientador: Carlos de Oliveira Paiva Santos / Banca: Edson Roberto Leite / Banca: Ivair Aparecido dos Santos / Banca: Ruth Herta Goldschimidt Aliaga Kiminami / Banca: Wanda Cecília Las / Doutor
6

The impact of type II diabetes and chronic periodontal disease on peripheral blood neutrophil apoptosis

Manosudprasit, Aggasit 28 September 2016 (has links)
Aims: to test the hypothesis that peripheral blood neutrophils (PMN) exhibit delayed spontaneous apoptosis in individuals with type 2 Diabetes, and that the delay is further exacerbated in individuals who co-express chronic periodontitis. Materials and methods: 73 individuals were enrolled, including those with type 2 diabetes (T2DM) (n=16), chronic periodontitis (CP) (n=15), diabetics with chronic periodontitis (T2DM+CP) (n=21) and healthy volunteers (n=21). PMN apoptosis was determined by flow cytometry using TUNEL and Annexin V assays. Caspase 3, 8 and 9 activity was measured by colorimetric assay. PMN surface death receptor quantification was performed by flow cytometry staining with fluorescence conjugated anti-CD120a (TNFR1) and anti- CD95 (FasR) antibody. Inflammatory biomarker analyses of serum samples were performed using multiplexed sandwich immunoassays. Results: In healthy volunteers, individuals with T2DM, CP and T2DM+CP, spontaneous PMN apoptosis observed at 12 hours reached 85.3% ± 3.1, 67.3% ± 3.9, 62.9% ± 3.5 and 62.5% ± 5.4, respectively (p<0.05 ). Caspase-3 activity was significantly reduced in individuals with T2DM and T2DM+CP (p<0.05), when compared to healthy volunteers. Caspase-8 activity was also significantly decreased in CP and T2DM+CP (p<0.05), associated with reduced cell surface Fas receptor, TNF receptors and Fas ligand serum levels. Glucose alone was not observed to effect PMN apoptosis; concurrent incubation with the RAGE agonist S-100B induced a significant PMN apoptosis (p<0.05). Conclusion: These data support the premise that the inhibition of PMN apoptosis in individuals with T2DM occurs through an AGE/RAGE ligand/receptor mediated interaction.
7

Avaliação de tratamento homeopático com Phytolacca decandra 30CH durante a lactação de vacas com mastite subclínica / Evaluation of homeopathic treatment with Phytolacca decandra 30CH during the lactation of cows with subclinical mastitis

Almeida, Leslie Avila do Brasil 13 May 2009 (has links)
O elevado custo dos tratamentos tradicionais da mastite bovina, associado à redução de produção e inviabilidade de tratamento das mastites subclínicas durante a lactação, bem como a exigência cada vez mais rigorosa da ausência de resíduos de antimicrobianos por parte de instituições nacionais e internacionais, impulsiona o desenvolvimento de novas alternativas terapêuticas que visem minimizar o impacto das medidas tradicionais de tratamento. A homeopatia surge como importante alternativa, sendo aceita nacional e internacionalmente. O objetivo do trabalho foi avaliar o tratamento homeopático com Phytolacca decandra 30CH durante a lactação de vacas com mastite subclínica, utilizando parâmetros de qualidade do leite como Califórnia Mastitis Test (CMT), contagem de células somáticas (CCS) totais, porcentagens de polimorfonucleares (PMN) e de mononucleares (MN), teores de proteína, lactose, gordura, sólidos totais (ST) e extrato seco desengordurado (ESD), além da mensuração da produção leiteira. Foram selecionadas 26 vacas, CMT 2+ e 3+ sem sinais de mastite clínica, entre o terceiro e sexto mês de lactação, pluríparas e divididas em dois grupos, um com tratamentos medicamentosos mensais e outro com tratamentos quinzenais. Mensalmente foram colhidas duas amostras de leite de cada glândula mamária (teto) que apresentava mastite subclínica. Uma das amostras foi utilizada para CCS e análise dos componentes do leite, e a outra para identificação microbiológica. Nos grupos tratados, foi administrado o medicamento homeopático Phytolaca decandra 30CH diluído em água e aspergido nas mucosas oro-nasais e vaginais, enquanto que nos grupos denominados controle foi administrado placebo da mesma maneira. A pesagem da produção láctea de ambos os grupos foi realizada quinzenalmente até o final do experimento. Verificou-se então que não houve diferença significativa entre a produção láctea, CCS e a presença de microrganismos na secreção láctea das glândulas quando comparadas antes e depois do tratamento homeopático, dentro de cada grupo, bem como quando comparados os grupos entre si. As medianas de CMT e porcentagens de PMN foram compatíveis com infecções mamárias agudas, embora os animais tenham sido diagnosticados como portadores de mastites crônicas e em nenhum momento desenvolveram sinais clínicos. / The high cost of traditional treatments of bovine mastitis, with the reduction of production and impracticable treatment of subclinical mastitis during lactation, as well as the requirement of an increased demand for absence of antimicrobial agents residues by national and international institutions, drives the development of new therapeutic alternatives in order to minimizing the impact of traditional treatment measures. The homeopathy appears as an important alternative, accepted domestically and internationally. The objective of this work was to evaluate homeopathic treatment with Phytolacca decandra 30CH during the lactation of cows with subclinical mastitis, using some milk quality parameters as California Mastitis Test (CMT), total somatic cell count (SCC), percentages of polymorphonuclear (PMN) and mononuclear (MN) cells, levels of protein, lactose, fat, total solids and dry defatted matter, in addition to the measurement of milk production. Twenty-six cows were selected with CMT 2 + and 3 + without any signs of clinical mastitis, between the third and sixth month of lactation, pluriparous and they were divided into two groups, with monthly or biweekly drug treatments. Monthly were collected two milk samples from each mammary gland (teat) that presented subclinical mastitis. One of the samples was used for analysis of SCC and milk components, and the other one for microbiological identification. In the treated groups, was given the homeopathic medicine Phytolaca decandra 30CH diluted in water and sprayed in the oral-nasal and vaginal mucosa, while to the control group was given placebo following the same method. The weighing of the milk production for both groups was performed fortnightly until the end of the experiment. There was no significant difference between milk production, SCC and the presence of microorganisms in milk gland secretion compared before and after homeopathic treatment, within each group as well as comparing the groups together. The medians of CMT and percentages of PMN were compatible with acute mammary infection, in spite of they have been diagnosed as carriers of chronic mastitis, and at any time no clinical signs have been developed.
8

Avaliação de tratamento homeopático com Phytolacca decandra 30CH durante a lactação de vacas com mastite subclínica / Evaluation of homeopathic treatment with Phytolacca decandra 30CH during the lactation of cows with subclinical mastitis

Leslie Avila do Brasil Almeida 13 May 2009 (has links)
O elevado custo dos tratamentos tradicionais da mastite bovina, associado à redução de produção e inviabilidade de tratamento das mastites subclínicas durante a lactação, bem como a exigência cada vez mais rigorosa da ausência de resíduos de antimicrobianos por parte de instituições nacionais e internacionais, impulsiona o desenvolvimento de novas alternativas terapêuticas que visem minimizar o impacto das medidas tradicionais de tratamento. A homeopatia surge como importante alternativa, sendo aceita nacional e internacionalmente. O objetivo do trabalho foi avaliar o tratamento homeopático com Phytolacca decandra 30CH durante a lactação de vacas com mastite subclínica, utilizando parâmetros de qualidade do leite como Califórnia Mastitis Test (CMT), contagem de células somáticas (CCS) totais, porcentagens de polimorfonucleares (PMN) e de mononucleares (MN), teores de proteína, lactose, gordura, sólidos totais (ST) e extrato seco desengordurado (ESD), além da mensuração da produção leiteira. Foram selecionadas 26 vacas, CMT 2+ e 3+ sem sinais de mastite clínica, entre o terceiro e sexto mês de lactação, pluríparas e divididas em dois grupos, um com tratamentos medicamentosos mensais e outro com tratamentos quinzenais. Mensalmente foram colhidas duas amostras de leite de cada glândula mamária (teto) que apresentava mastite subclínica. Uma das amostras foi utilizada para CCS e análise dos componentes do leite, e a outra para identificação microbiológica. Nos grupos tratados, foi administrado o medicamento homeopático Phytolaca decandra 30CH diluído em água e aspergido nas mucosas oro-nasais e vaginais, enquanto que nos grupos denominados controle foi administrado placebo da mesma maneira. A pesagem da produção láctea de ambos os grupos foi realizada quinzenalmente até o final do experimento. Verificou-se então que não houve diferença significativa entre a produção láctea, CCS e a presença de microrganismos na secreção láctea das glândulas quando comparadas antes e depois do tratamento homeopático, dentro de cada grupo, bem como quando comparados os grupos entre si. As medianas de CMT e porcentagens de PMN foram compatíveis com infecções mamárias agudas, embora os animais tenham sido diagnosticados como portadores de mastites crônicas e em nenhum momento desenvolveram sinais clínicos. / The high cost of traditional treatments of bovine mastitis, with the reduction of production and impracticable treatment of subclinical mastitis during lactation, as well as the requirement of an increased demand for absence of antimicrobial agents residues by national and international institutions, drives the development of new therapeutic alternatives in order to minimizing the impact of traditional treatment measures. The homeopathy appears as an important alternative, accepted domestically and internationally. The objective of this work was to evaluate homeopathic treatment with Phytolacca decandra 30CH during the lactation of cows with subclinical mastitis, using some milk quality parameters as California Mastitis Test (CMT), total somatic cell count (SCC), percentages of polymorphonuclear (PMN) and mononuclear (MN) cells, levels of protein, lactose, fat, total solids and dry defatted matter, in addition to the measurement of milk production. Twenty-six cows were selected with CMT 2 + and 3 + without any signs of clinical mastitis, between the third and sixth month of lactation, pluriparous and they were divided into two groups, with monthly or biweekly drug treatments. Monthly were collected two milk samples from each mammary gland (teat) that presented subclinical mastitis. One of the samples was used for analysis of SCC and milk components, and the other one for microbiological identification. In the treated groups, was given the homeopathic medicine Phytolaca decandra 30CH diluted in water and sprayed in the oral-nasal and vaginal mucosa, while to the control group was given placebo following the same method. The weighing of the milk production for both groups was performed fortnightly until the end of the experiment. There was no significant difference between milk production, SCC and the presence of microorganisms in milk gland secretion compared before and after homeopathic treatment, within each group as well as comparing the groups together. The medians of CMT and percentages of PMN were compatible with acute mammary infection, in spite of they have been diagnosed as carriers of chronic mastitis, and at any time no clinical signs have been developed.
9

Avaliação dos medicamentos homeopáticos Sulphur 30CH e Calcarea carbonica 30CH para tratamento de vacas com mastite subclínica / Evaluation of homeopathic Sulphur 30CH and Calcarea carbonica 30CH for treatment of cows with subclinical mastitis

Sakiyama, Débora Tieko Parlato 22 September 2010 (has links)
O uso de antibióticos para tratamento da mastite bovina subclínica durante a lactação apresenta restrições econômicas e a administração indiscriminada e inadequada destes medicamentos os torna potencialmente tóxicos aos animais e aos consumidores finais dos produtos lácteos. A utilização de medicamentos homeopáticos oferece menor custo, facilidade de administração, não há risco de resistência microbiana e não é necessário o descarte do leite dos animais em tratamento. Além disso, a homeopatia é reconhecida no Brasil como especialidade médica veterinária e aceita para uso no sistema de produção animal orgânico. Portanto, o presente trabalho teve como objetivo avaliar a eficácia de dois protocolos homeopáticos para tratamento da mastite bovina subclínica durante a lactação. O experimento foi realizado no período de seis meses e dividido em duas etapas. Na Etapa I, um grupo foi medicado com Sulphur 30CH, enquanto que o outro recebeu placebo. Na Etapa II, um grupo foi medicado com Calcarea carbonica 30CH e o outro grupo recebeu placebo. Os medicamentos foram administrados a cada trinta dias na Etapa I e a cada quinze dias na Etapa II. Em cada etapa foram coletadas amostras de leite antes, durante e após o tratamento. Para avaliar a eficácia dos protocolos, durante o experimento foram analisadas 138 amostras de leite na Etapa I e 72 amostras na Etapa II, realizando-se prova de Tamis, California Mastitis Test (CMT), contagem de células somáticas (CCS), quantificação de polimorfonucleares (PMN) e mononucleares (MN) por microscopia óptica, exame microbiológico e mensuração da produção leiteira. As análises estatísticas foram realizadas utilizando o software Graphpad Instat 1990-93. Os protocolos homeopáticos testados não diminuíram a celularidade do leite, pois não houve diferenças significativas nos resultados do CMT e da CCS no decorrer do experimento. Também não foi constatada nenhuma alteração significante na produção láctea. O microrganismo isolado com maior frequência no rebanho estudado foi o Corynebacterium bovis. Porém, não houve diferenças significativas em relação à frequência de isolamento deste microrganismo ao longo dos tratamentos, indicando a sua permanência nas glândulas mamárias. Além disso, observou-se durante todo o experimento o predomínio de células PMN em relação às MN. Sugere-se o estudo de novos protocolos homeopáticos com outros medicamentos, potência e frequência de administração, a fim de buscar alternativas para o tratamento de vacas com mastite subclínica / The use of antibiotics for treatment of bovine subclinical mastitis during lactation presents economic restrictions and the indiscriminate and inappropriate administration of these drugs makes them potentially toxic to animals and consumers of dairy products. The use of homeopathic medicine offers lower cost, ease of administration, no risk of microbial resistance and is not necessary to discard milk from animals under treatment. Furthermore, homeopathy is recognized as a medical specialty in Brazil and support for veterinary use in organic livestock production system. Therefore, this study aimed to evaluate the effectiveness of two protocols for homeopathic treatment of bovine subclinical mastitis during lactation. The experiment was performed between six months and divided into two stages. In Phase I, one group was treated with Sulphur 30CH, while the other received placebo. In Phase II, one group was treated with Calcarea carbonica 30CH and the other group received placebo. The drugs were administered every thirty days in the Phase I and every fifteen days in the Phase II. At each step the milk samples were collected before, during and after treatment. To evaluate the effectiveness of the protocols during the experiment were analyzed 138 samples of milk at Phase I and 72 samples at Phase II, performing proof Tamis, California Mastitis Test (CMT), somatic cell count (SCC), quantification of polymorphonuclear (PMN) and mononuclear (MN) by optical microscopy, microbiological examination and measurement of milk production. Statistical analysis was performed using the software Graphpad Instat 1990-93. The homeopathic protocols tested not diminished cellularity of milk because there were no significant differences in the results of CMT and SCC during the experiment. Nor was it found no significant change in milk production. The organism isolated most frequently in the herd studied was Corynebacterium bovis. However, no significant differences were observed in the frequency of isolation of this microorganism during the treatments, indicating his permanence in the mammary glands. Furthermore, it was observed during the experiment a predominance of PMN cells compared to MN. It is suggested the study of new protocols with other homeopathic medicines, potency and frequency of administration, to find alternatives for the treatment of cows with subclinical mastitis
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Síntese de filmes finos do sistema PMN-PT pelo método dos precursores óxidos

Rodrigues, Daniela Cristina Manfroi [UNESP] 29 April 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-29Bitstream added on 2014-06-13T20:47:02Z : No. of bitstreams: 1 rodrigues_dcm_me_ilha.pdf: 1395984 bytes, checksum: 5f52de55e2329a979bca9d5a8878bbb1 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho realizou uma investigação acerca da síntese de filmes finos do sistema PMN-PT utilizando o método dos precursores óxidos, associado a uma resina polimérica resultado de uma reação de condensação entre o ácido cítrico e o etileno glicol, e algumas de suas variações a fim de investigar o impacto da rota de síntese empregada sobre as fases formadas nos filmes finos. O estudo do comportamento desta resina submetida a diversas temperaturas, através do uso da técnica de espectroscopia no infravermelho, apontou que para a rota de síntese proposta os metais são incorporados à resina polimérica através de fortes ligações coordenadas com os grupos carboxilas do ácido cítrico (COO-). Também mostrou que temperaturas acima de 400°C favorecem a decomposição da cadeia orgânica e a liberação destes metais, que podem reagir com o oxigênio formando uma fase cristalina. O uso da técnica de difratometria de raios-X para a investigação das fases formadas nos filmes finos produtos de diversas modificações na síntese, apontou principalmente a dificuldade em obter os filmes livres de fases secundárias, como pirocloro, MgNb2O3,67, Mg3Nb6O11 e Pb3O4. Os principais fatores levantados para o aparecimento destas fases são: sublimação de metais como Pb e Mg levando a mudanças na estequiometria, excesso de matéria orgânica que acarreta numa pirólise descontrolada da cadeia polimérica levando à formação de aglomerados. A composição do polímero (razão ácido cítrico:etilenoglicol) pode favorecer a formação da fase desejada. Salientando ainda que os tratamentos térmicos tem importante colaboração na formação de fases, pois a diminuição do tempo durante o qual a amostra fica exposta a uma determinada temperatura pode ajudar na formação da fase desejada. O estudo desta rota de síntese forneceu filmes finos com a fase perovskita, porém... / This study conducted a research on the synthesis of PMN-PT thin films using the method of precursor oxides and some of its variants to investigate the impact of the route of synthesis employed on the phases formed in thin films. The behavior of the polymeric resin, subjected to different heat treatments, was investigated by infrared spectroscopy, showed that for the proposed route of synthesis the metals are incorporated into the polymeric resin through strong coordinated bonds with the hydroxyl group of citric acid (COO-). Temperatures above 400°C promote the pyrolysis of polymer and the release of these metals, which react with oxygen and form a crystalline phase for investigation of phases formed in thin films from changes in the synthesis, the X-ray diffraction technique was used. Mainly pointed to the difficulty to get thin films free of secondary phases, as pyrochlore, MgNb2O3,67, Mg3Nb6O11 and Pb3O4. The major factors for the appearance of these phases are: sublimation of metals such as Pb and Mg leading to losses in the composition, uncontrolled pyrolysis of a polymer chain caused by excess of the organic matter, that lead to form clusters. The composition of the polymer (ratio citric acid: ethylene glycol) may promote the perovskite phase formation. Emphasizing, the heat treatment has an important relationship on formation of phases, because the decrease of the time which the sample is exposed to heat can lead to form the desired phase, as could be observed. These route of synthesis lead to formation of perovskite phase in thin films, but the secondary phases elimination, including pirocloro, still need to be more investigated.

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