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Método generalizado do grupo de renormalização numérico para o cálculo de propriedades termodinâmicas de impurezas em metais. / Generalized numerical renormalization group method to calculate the thermodynamical properties of impurities in metals.Oliveira, Wanda da Conceicao de 20 May 1994 (has links)
Este trabalho tem como objetivo desenvolver uma técnica de calculo que permita diagonalizar Hamiltonianos de mais de uma impureza e adaptá-la ao calculo de suas propriedades termodinamicas. Esta técnica é uma extensão do método de grupo de renormalização, originalmente desenvolvido por Wilson para calcular propriedades termodinâmicas do modelo Kondo de uma impureza. O procedimento baseia-se na discretização logarítmica da banda de condução do metal hospedeiro, definida por um parâmetro de discretização Λ, que permite que se projete o Hamiltoniano em uma base quântica finita, na qual o mesmo possa ser diagonalizado numericamente. O tempo do custo computacional do calculo diminui exponencialmente à medida que Λ cresce, tornando melhor trabalharmos com valores grandes de Λ. O grande problema em usarmos Λ grande e que aparecem oscilações nas curvas das propriedades termodinâmicas. Neste trabalho apresentamos o método generalizado que elimina essas oscilações. Inicialmente, testamos o método no modelo de Anderson sem correlação de uma impureza para o cálculo da suscetibilidade magnética do sistema, com resultado satisfatório. Na seqüência, para verificar a potencialidade do método, diagonalizamos o Hamiltoniano de Falicov, Kimball e Ramirez (sem spin) do modelo de duas impurezas e calculamos a suscetibilidade de carga da impureza. A motivação para esse cálculo e a equivalência existente entre o Hamiltoniano de Vigman e Finkelshtein e o Hamiltoniano Kondo, para o modelo de uma impureza. No caso de duas impurezas o nosso calculo demonstra que a interação RKKY destrói essa equivalência, ainda que qualitativamente as curvas da suscetibilidade de carga neste modelo reproduzam as de suscetibilidade magnética do modelo Kondo. / This thesis develops an extension of the numerical renormalization - group method. The extended procedure is capable of computing the temperature dependence of the magnetic susceptibility for two-impurity models of dilute magnetic alloys. The renormalization-group approach was devised by Wilson to calculate the thermodynamical properties for the one-impurity Kondo model. The numerical procedure is based on a logarithmic discretization of the conduction band of the metallic host, which is defined by a dimensionless parameter Λ > 1, equal to the ratio of two sucessive discrete energies. Once the conduction Hamiltonian is discretized, the model Hamiltonian reduces to a discrete series that can be diagonalized numerically. The computational cost of the diagonalization diminishes exponentially with 1/ ln Λ, which makes it attractive to work with large Λ. unfortunately, the thermodynamical averages computed with Wilson\'s original version of the numerical renormalization group method and large Λ, computed as function of the temperature, display artificial oscilations with period ln Λ and amplitude proportional to e-▂/lnΛ. By contrast, the generalized procedure in this work produces thermal dependences that converge so rapidly to the continuum (Λ + 1) limit that curves computed with Λ=10 are virtually identical with those calculated with Λ=3 in the original procedure. As an illustration, we have diagonalized a two-impurity version of the (spinless) Falicov-Kimball-Ramirez Hamiltonian and calculated its charge susceptibility. This application was motivated by the well-established equivalence between the single-impurity (spinless) Vigman-Finkelshtein and Kondo models. In the case of two impurities, our work shows tha the RKKY interaction destroys the equivalence between the two models. Nonetheless, the charge susceptibility curves for the two-impurity Falicov-Kimball-Ramirez model show the qualitative features of the magnetic susceptibility for the two-impurity Kondo model.
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Genetic susceptibility to type II diabetes and obesity : the role of UCP2, UCP3 and CAPN10 genesCassell, Paul Geoffrey January 2002 (has links)
The global prevalence of type 2 diabetes (T2DM) and obesity is increasing, with obesity the most important predisposing factor contributing to the development of T2DM. Epidemiological and genetic evidence supports a major genetic component in both multifactorial and heterogeneous disorders. The identification of disease susceptibility genes in humans could greatly assist in the elucidation of underlying pathophysiological mechanisms and allow the development of more effective preventative and therapeutic strategies for these conditions. Three candidate genes, uncoupling proteins 2 and 3 (UCP2; UCP3) and calpain 10 (CAPN10), are proposed and the rationale for their selection discussed. Gene variants were identified in UCP2 and UCP3. These variants were tested for association with T2DM, obesity and intermediate quantitative traits in a South Indian population and family collection, and also a cohort of British obese case/control subjects. No variant was associated with T2DM. However, investigations revealed positive associations with a UCP2 3'UTR 45bp Ins/Del and a novel UCP3 promoter variant (-55C/T) with variation in body mass (BMI) and fat distribution (WHR) respectively. The results support the view that uncoupling proteins may influence weight gain and hence progression to obesity/T2DM. A significant correlation with plasma leptin levels and the UCP2 Ins/Del variant might indicate one potential mechanism whereby weight could be modulated by uncoupling proteins. A linkage study in affected sibling pairs of North European descent, was negative for the putative T2DM susceptibility gene region, NIDDMI. In contrast, haplotypes of four sequence variants of a T2DM susceptibility gene (CAPN10) identified in this region positively associated with T2DM in a South Indian population. In conclusion, these investigations provide evidence that the three genes studied may contribute to susceptibility for development of T2DM or obesity. However, the findings are in agreement with the most likely genetic model for non-Mendelian complex diseases, that many genes are involved in determining susceptibility to disease with no single gene capable of determining the overall disease phenotype.
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AC susceptibility studies under hydrostatic pressureMcCann, Duncan Michael January 2017 (has links)
AC susceptibility is an important characterisation technique measuring the time dependent magnetisation and dynamics of a magnetic system. It is capable of yielding information on thermodynamic phase transitions, relaxation processes and losses in a variety of interesting magnetic and superconducting materials. In particular it is a powerful probe of the mixed state of superconductivity providing insight into the ux dynamics at play and determination of a number of physical properties such as the critical temperature Tc, field Hc and characteristic length scales. Application of pressure can tune materials through multiple phases and interesting phenomena. The thesis describes the design of a calibratable susceptometer in a piston cylinder pressure cell, achieving AC susceptibility measurements of the same accuracy as a SQUID magnetometer but under pressure. This is used to make measurements on an electrostatically doped capacitance device, a single chain magnet and a heavy fermion superconductor. These studies are summarised below. Electric double layer (EDL) devices provide a means of continuous tuning through a materials phase diagram by applying an electric field, including inducing superconductivity. Application of pressure in tandem with electrostatic doping could improve the efficiency of these devices and provide a second tuning parameter. An EDL capacitor was constructed and measured with the above susceptometer aiming to shift the Tc of a doped high temperature superconducting cuprate La1:9Sr0:1CuO4. The Tc shifts proved irreproducible already at ambient conditions. Indeed during the course of this research further experimental evidence emerged in the literature indicating EDL devices may very well work due to electrochemical doping rather than electrostatic, possibly accounting for the lack of repeatability. Work therefore focused on mapping the ionic liquid DEME-TFSI's glass-liquid phase diagram over the 1 GPa pressure range, rather than extending the study of the EDLC device to high pressure. Single chain magnets (SCM) are an interesting class of material consisting of a one-dimensional molecular magnet chain manifesting magnetic hysteresis and slow relaxation best characterised by AC susceptibility. The susceptometer was used to study the SCM [Co(NCS)2(pyridine)2]n to investigate the effect of pressure on its characteristic magnetic relaxation time and energy barrier. A secondary signal appears at ~0.44 GPa which is attributed to the development of an additional structural phase that has been independently observed in X-ray crystallographic measurements. The heavy fermion superconductor U6Fe has the highest Tc ~4 K of all the U-based compounds and large critical fields of ~10-12.5 T, depending on direction, which increase on initial application of pressure. It exhibits a coexisting charge density wave (CDW) below 10 K making it a promising candidate for the modulated superconductivity of the theorised Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state. A feature at 110 K is also evident in Mossbauer, resistivity and specific heat measurements, the origin of which has not yet been clearly identified. Evidence for the FFLO state was sought by mapping the upper critical field Hc2 along with the peak effect through AC susceptibility measurements up to pressures of 1 GPa. The data is accounted for by an evolution of collective pinning and superconducting parameters, with no clear evidence for an FFLO state although an enhancement of the reduced field is observed.
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Suscetibilidade de microorganismos relacionados com a contaminação de alimentos em biofilme artificial e em suspensão frente a desinfetantes /Cabeça, Tatiane Karen. January 2006 (has links)
Orientador: Elisabeth Loshchagin Pizzolitto / Banca: Jonas Contiero / Banca: Cristina Paiva de Sousa / Resumo: Avaliou-se o perfil de suscetibilidade de Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 25922 e Listeria monocytogenes ATCC 7644, em suspensão e em biofilme formado in vitro, frente à ação dos desinfetantes: ácido iodado, à base de biguanida, à base de quaternário de amônio, à base de ácido peracético e clorado, empregados comumente em indústrias alimentícias brasileiras. As técnicas de microscopia eletrônica de varredura e microbiológica de viabilidade celular foram utilizadas para esta pesquisa. Os resultados demonstraram que as células microbianas em suspensão foram suscetíveis a ação de todos os desinfetantes estudados, não apresentando células viáveis após 10 minutos de tratamento com os desinfetantes. O desinfetante clorado foi o mais eficaz na eliminação das células microbianas em biofilme, proporcionando baixos valores numéricos na contagem das células viáveis e poucas células aderidas à superfície do aço inoxidável após submetido ao tratamento de 10 minutos, enquanto o desinfetante à base de biguanida mostrou ser o menos eficaz na eliminação das células microbianas em biofilme após um tratamento de 10 minutos. A idade do biofilme em horas (24, 75, 120) não mostrou ser um fator influente na resistência das células microbianas aos desinfetantes testados. Comparando-se os resultados da suscetibilidade das células microbianas em suspensão e em biofilme, foi verificado que as células em biofilme são mais resistentes à ação dos desinfetantes. O conjunto dos resultados sugerem uma deficiência de todos os desinfetantes estudados na eliminação de S. aureus, E. coli e L. monocytogenes quando em biofilme. / Abstract: The susceptibility of Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 25922 and Listeria monocytogenes ATCC 7644, in suspension and in biofilm formed in vitro, was studied against the action of disinfectants: iodine, biguanide, quaternary ammonium, peracetic acid and chlorine, commonly used in Brazilian food industries. The scanning electron microscopy and cellular viability techniques were used in this research. The results showed that the microbiological suspension cells were susceptible after 10 minutes of treatment with the disinfectants. The chlorine disinfectant was the most effective against microbiological cells in biofilm, showed low numbers of viable cells and few adhered cells on stainless steel surface after 10 minutes of treatment, while the biguanide disinfectant showed to be the least effective against microbiological cells in biofilm after 10 minutes of treatment. The biofilm age in hours (24, 72 and 120) didn't show to be an influential factor on resistance of microbiological cells to studied disinfectant. The comparison between the results of susceptibility of microbiological suspension cells and microbiological biofilm cells showed that the biofilm cells are more resistant to disinfectants action. The results suggest that the studied disinfectants could not eliminate S. aureus, E. coli and L. monocytogenes biofilms. / Mestre
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Avaliação da atividade in vivo e in vitro da terbinafina e itraconazol frente ao sporotrix schenckii / Evaluation of the activity in vivo and in vitro of the terbinafine and itraconazole against to the Sporothrix schenckiiMeinerz, Ana Raquel Mano January 2007 (has links)
Considerando a importância do felino doméstico nos relatos zoonóticos da esporotricose, assim como os problemas relacionados a terapêutica da micose nessa espécie, o estudo objetiva avaliar a atividade in vitro da terbinafina e itraconazol frente ao S. schenckii; estudar a ação desses fármacos no tratamento da esporotricose sistêmica experimental; analisar as enzimas hepáticas e hemograma dos animais submetidos ao tratamento antifúngico; estudar as possíveis alterações macroscópicas nos animais inoculados com S. schenckii assim como realizar o retroisolamento do agente. Para o teste in vitro, foram utilizados 10 isolados de S. schenckii (seis felinos, três humanos e um de cão), os quais foram avaliados quanto a suscetibilidade frente aos fármacos através da técnica de microdiluição em caldo de acordo com o CLSI para as fases leveduriforme e filamentosa do agente. A leitura da CIM foi visual, correspondendo à menor concentração do antifúngico em que não houve crescimento visível do S. schenckii quando comparado ao controle positivo. O teste in vivo, foi realizado através da inoculação pelas vias intraperitonial e veia lateral da cauda de células fúngicas (2x103 cél/mL) de dois isolados de S. schenckii (felino e canino) em 120 ratos norvergicus, divididos em quatro grupos: tratado terbinafina (250mg/kg) e itraconazol (100mg/kg); diluente terbinafina (250mg/kg de solução de água destilada com 5% de DMSO e 1% de Tween 20) e itraconazol (100mg/kg de água destilada estéril), sendo administrados através de sondagem oral uma vez ao dia, durante 30 dias. Paralelamente foram realizados hemogramas e avaliação das enzimas hepáticas (ALT e FA), assim como o acompanhamento da evolução clínica e análise histopatológica de todos animais experimentais. No final do período experimental os animais foram necropsiados e realizado análise macroscópica com a coleta dos órgãos para a obtenção do retroisolamento do S. schenckii. A CIM para a terbinafina obtida entre todos os isolados na fase leveduriforme de esporotricose felina variaram de 0,055μg/mL a 0,109μg/mL, enquanto que para os isolados humanos e de cão foi de 0,055μg/ml. Para o itraconazol, a CIM frente aos isolados de esporotricose felina foi de 0,875μg/mL a 1,75μg/mL, já para os casos humanos foi de 0,219μg/mL e para o isolado de cão de 1,75μg/mL. Para a fase filamentosa do agente foi observada uma CIM para a terbinafina entre os isolados de felinos de 0,875 μg/mL, enquanto que os isolados humanos e de cão a CIM foi de 0,219μg/mL. Para o itraconazol os isolados felinos resultaram numa CIM de 3,5μg/mL, já nos isolados de esporotricose humana e em cão a CIM foi de 1,75μg/mL. Quanto ao estudo in vivo, os animais tratados com terbinafina e itraconazol resultaram em menor freqüência de alterações macroscópicas assim como na obtenção do retroisolamento do agente em relação aos grupos controle. Não foi detectada alterações nas enzimas hepáticas, hemograma e nas avaliações macro e histopatológicas dos animais submetidos ao tratamento antifúngico. Com esses resultados conclui-se que a terbinafina e itraconazol possuem atividade in vitro frente ao S. schenckii e que as doses estudadas dos fármacos são eficazes no tratamento da esporotricose experimental sistêmica, assim como não produzem alterações das enzimas hepáticas avaliadas e do hemograma. / Considering the importance of the domestic feline in the zoonotic reports of the esporotrichosis, as well as the related problems the therapeutics of the mycosis in that species, the study objective was evaluate the activity in vitro of terbinafine and itraconazole against to S. schenckii; study the activity of those drugs in the treatment of the experimental systemic esporotrichosis; analyze the hepatic enzymes and blood count of the animals submitted to the antifungal treatment; study the possible macroscopic alterations in the animals inoculated with S. schenckii as well as realized the agent retroisolament. For the test in vitro, 10 isolated of S. schenckii were used (six felines, three humans and one canine), which were performed as the susceptibility against to the drugs through the microdiluição technique in broth in accordance with the CLSI for the phases yeast and mycelial of the agent. The reading of CIM was visual, corresponding to smallest concentration of the antifungal in that there was not visible growth of S. schenckii when compared to the positive control. The test in vivo, was performed through the of the inoculation intraperitonial and lateral vein of the tail of fungal cells (2x103 cél/mL) of two isolated of S. schenckii (feline and canine) in 120 mice norvergicus, divided in four groups: treaty terbinafine (250mg/kg) and itraconazole (100mg/kg); diluent terbinafine (250mg/kg of solution of water distilled with 5% of DMSO and 1% of Tween 20) and itraconazol (100mg/kg of water distilled sterile), being administered by gavage once a day, for 30 days. Parallel blood counts and evaluation of the hepatic enzymes were accomplished (ALT and F.A), as well as the accompaniment of the clinical evolution and analysis histopathologic of all animal experimental. In the end of the experimental period the animals were autopsied and performed macroscopic analysis with the collection of the organs for the obtaining of the detected S. schenckii growth. CIM for the terbinafine obtained among all the isolated in the phase yeast of feline esporotrichosis oscillated between 0,055μg/mL the 0,109μg/mL, while for the isolated humans and canine was of 0,055μg/ml. For the itraconazole, the CIM against of the isolated of feline esporotrichosis was from 0,875μg/mL to 1,75μg/mL, for the human cases it went of 0,219μg/mL and for the isolated canine of 1,75μg/mL. For the mycelial phase a CIM was observed for the terbinafine among the isolated of felines of 0,875 μg/mL, while the isolated humans and canine CIM was of 0,219μg/mL. For the itraconazole the isolated felines resulted in a CIM 3,5μg/mL, in the isolated of human esporotrichosis and canine CIM was of 1,75μg/mL. As for the study in vivo, the animals treaties with terbinafine and itraconazole resulted in smaller frequency of macroscopic alterations as well as in the obtaining of the detected agent growth in relation to the groups control. It was not detected alterations in the hepatic enzymes, blood count and in the evaluations macro and histopathologic of the animals submitted to the antifungal treatment. With those results we are to report that the terbinafine and itraconazol apresent activity in vitro against to S. schenckii and that the studied doses of the drugs are effective in the treatment of the systemic experimental esporotrichosis, as well as they don't produce alterations of the appraised hepatic enzymes and blood count.
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Human parainfluenza virus 3 : genetic diversity, virulence and antiviral susceptibilitySmielewska, Anna Alexandra January 2019 (has links)
Human parainfluenza 3 (HPIV3) is a member of the Paramyxoviridae, a single strain negative-sense non-segmented RNA virus in the order Mononegavirales. It is a respiratory pathogen with a broad spectrum of presentations for which there is currently neither a vaccine nor licensed treatment for HPIV3. To date most research on HPIV3 has been conducted using significantly culture adapted reference strains. Therefore, minimally adapted clinical strains were grown in two cell culture systems: immortalised and primary. Plaque phenotype, growth kinetics and inflammatory response triggered were evaluated and it was found that there is a range of phenotypes exhibited by clinical strains with potential implications in vivo. To examine the genetic diversity of circulating strains of HPIV3 in the UK, a new amplicon based sequencing pipeline for whole genome sequencing of HPIV3 was developed and validated. A short hypervariable region in the HPIV3 genome was identified and evaluated as a potential candidate for subsequent phylogenetic analysis compared to whole genome data. This method was then applied to tracking an HPIV3 outbreak that took place on a paediatric oncology ward. It was found to be a point-source outbreak and the clinical impact in this setting, as well as the infection control procedures involved were evaluated. Finally a robust in vitro model for the evaluation of potential therapeutic candidates for HPIV3, based on a panel of minimally passaged clinical strains as well as a culture-adapted reference strain, was set up. This model was applied to three potential inhibitors of HPIV3: ribavirin, favipiravir and zanamivir. The results showed that clinical strains were at least as susceptible to ribavirin and favipiravir as the laboratory reference strain and significantly more susceptible to zanamivir. This indicates that further work on minimally adapted clinical strains is essential to further the understanding of this important virus.
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A suscetibilidade à rubéola das gestantes, Bauru, 1987 / Rubella susceptibility of pregnant women, Bauru, 1987Sato, Neusa Nakao 26 April 1993 (has links)
A vacinação contra a rubéola tem como objetivo único, a proteção de futuras gerações de crianças em desenvolver a rubéola congênita. Gregg40, em 1941, levantou a hipótese de a rubéola ser a causa do nascimento de crianças com graves malformações congênitas. A confirmação etiológica só foi possível em 1962, com o isolamento do vírus, o que permitiu o desenvolvimento da vacina. A vacina foi utilizada, a partir de 1969, nos Estados Unidos e na Inglaterra e, atualmente, faz parte dos programas de vacinação de rotina na maioria dos países desenvolvidos. As experiências de mais de duas décadas no uso da vacina nos programas de controle da SÍNDROME DA RUBÉOLA CONGÊNITA (SRC) mostraram que a epidemiologia da rubéola, assim como a operacionalização das metas propostas para a cobertura vacinal são bastante complexas. As características do vírus, na sua interação com a população humana, determinam um padrão de transmissibilidade que propicia a formação de bolsões de indivíduos suscetíveis na idade adulta. Em condições naturais, a rubéola infecta cerca de 80 por cento a 90 por cento das pessoas até os 20 anos de idade, deixando um resíduo de indivíduos suscetíveis a partir desta idade, que, aparentemente, se mantém mesmo com epidemias sucessivas. O nascimento de crianças com SRC está condicionado à infecção rubeólica durante a gestação das mães destas crianças, portanto, a existência de mulheres suscetíveis à rubéola na idade fértil é uma condição fundamental à ocorrência da doença. O óbito de crianças malformadas detectadas em alguns meses do ano de 1986 chamou a atenção dos epidemiologistas do Município de Bauru para uma possível associação com a epidemia de rubéola ocorrida na cidade em 1985. Conhecer a proporção de suscetibilidade à rubéola entre gestantes é uma das maneiras para se estimar o risco de ocorrência de SRC. Em 1987, 689 gestantes residentes no Município de Bauru foram entrevistadas e submetidas a teste de inibição de hemaglutinação para determinação de suscetibilidade à rubéola. Destas gestantes, 66 (9,7 por cento ) foram consideradas suscetíveis à rubeóla. Não houve diferença estatisticamente significante na proporção de suscetibilidade das gestantes em relação à idade, número de gestações, paridade e idade gestacional, o que de certa forma confirma a dificuldade do vírus da rubéola em infectar todas as pessoas até o início da idade adulta, mesmo após uma epidemia. Este resíduo de suscetibilidade dificilmente seria eliminado naturalmente, como mostram as diferentes experiências nos países que iniciaram um programa de controle da SRC. Seria necessária uma alta cobertura vacinal (cerca de 95 por cento ) de todas as coortes de crianças e adolescentes para se conseguir a quebra na cadeia do processo infeccioso. Concomitantemente, é decisiva a proteção de todas as mulheres em idade fértil até que, estas coortes de indivíduos bem imunizados atinjam a idade fértil. Uma intervenção desta natureza não poderia ser implementada sem o respaldo de um sistema de vigilância epidemiológica fortalecido e atuante, capaz de monitorar não apenas o andamento do programa, mas, fundamentalmente, medir o impacto desta intervenção em termos de incidência de SRC. Considerando as características de polimorfismo da SRC e as dificuldades em se medir a magnitude da infecção congênita, a avaliação de um programa que envolve pelo menos duas gerações de indivíduos é um grande desafio para os administradores de saúde, principalmente, nos países em desenvolvimento. / The vaccination against rubella has as the only objectif to protect the future generations of children from the congenital rubella. Gregg, in 1941, supposed that the rubella should be the cause of birth of children with serious congenital abnormalities. The etiologial confirmation was only possible in 1962, by the isolation of virus, which allowed the development of vaccine. Firstly, utilized in the United States and Great Britain, in 1969, nowadays the vaccine is used in most developed countries. Experiences performed during more than two decades in usage of the vaccines during the Congenital Rubella Syndrome Control Program, showed that the epidemiology of the rubella, as well as, the exequibility of proposed aims for the vaccinal coverture are quite complex. The virus characteristics and its interactions with the population, determine a transmissibility pattern, which provides the formation of susceptible \"cluster\" in the adult age. In natural conditions, the rubella infects about 80 per cent to 90 per cent of people up to the age of twenty, leaving a susceptible remains after this age, which, apparently, it is maintained even with continuous epidemics. As the CRS children birth is connected to the rubella infection during the gestacional age of those mothers, the existence of susceptible childbearing age women is the most important condition for the disease to break out. In 1985, in the City of Bauru (São Paulo), abnormal number of death of congenital abnormalities children was focused by local epidemilogists. This fact was supposed, by the epidemiologists, being associated to a rubella epidemic in the year before. One of the ways to estimate the risk of occurance of RCS is to know the level of susceptibility among pregnant women. In 1987, 689 pregnant women, dwelling in the City of Bauru, were interviewed and went through a haemagglutination-inibition test in order to determine the susceptibility to rubella. Sixty-six out of these pregnant women was considered susceptible to rubella. There was not any difference statistically significant in the susceptible proportion of the pregnant women related to age, number of pregnancies, number of deliveries and gestacional age which somehow confirm the difficult of the rubella virus to infect all people up the beginning of the adult age, even after an epidemic. This susceptible remains would hardly ever be eliminated naturaly, as it is shown in the different experiences in countries, which began the RCS Control Program. The experiences showed that it would possibly, be necessary a high vaccinal coverture (about 95 per cent ) of all generations of children and adolescents in order to get the break of the infection process chain. Concomitantly, the protection of all women in childbearing age is important, until these generations of well vaccinated individuais reach the childbearing age. Such intervention should not be implemented without the agreement of an epidemiological surveillance system, both dynamic and strong, in order to monitore not only, the follow up of the program, but also, to measure the impact of this intervention in terms of RCS incidence. Considering the RCS characterists of polimorfism and the difficulties to evaluate the magnitude of congenital infection, the evaluation of a program that involves, at least, two generations of individuais, is a great challenge for the health administars, specially, in developing countries.
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Planejamento varietal de cana-de-açúcar utilizando suscetibilidade magnética do solo /January 2019 (has links)
Resumo: A falta de detalhamento nas informações sobre os atributos do solo, nas áreas cultivadas é um fator limitante para aumentar a assertividade na alocação de variedades de cana-de-açúcar em diversos ambientes edafoclimáticos. Atualmente, o conceito de ambientes de produção é amplamente utilizado para classificar o potencial de produtividade dos solos, e a suscetibilidade magnética surge como uma ferramenta importante para mapear áreas de forma ultradetalhada e com baixo custo. Nesse contexto, este trabalho tem como objetivo avaliar a utilização da suscetibilidade magnética como ferramenta na identificação de áreas com diferentes potenciais para produtividade e qualidade de cana-de-açúcar e sua utilização na alocação de variedades. Foram amostrados 445 ha com grid de 1 ponto a cada 5 hectares e, seguindo o espigão da paisagem, foram determinados 14 pontos para amostragem estratificada. Analisaram-se a granulometria e a suscetibilidade magnética de amostras, nas profundidades de 0,0-0,2 m e 0,2-0,4 m. Os dados de produtividade e de qualidade da matéria-prima foram obtidos via banco de dados de 9 safras e biometria realizada na safra de 2018/2019. Como resultados, observou-se alta correlação dos teores de argila e de areia com a expressão magnética. Pela análise multivariada dos resultados históricos, observou-se a organização de 3 grupos com diferentes potenciais de produtividade e de qualidade, diferenciando em até 17,28TCH o resultado entre o grupo com maior e menor potencial, b... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The lack of detail in the information on soil attributes in cultivated areas is a limiting factor to increase assertiveness in the allocation of sugarcane varieties in various edaphoclimatic environments. Nowadays, the concept of production environments is used to classify soil execution potential and a magnetic increase in susceptibility as an important tool for mapping ultra-detailed and low cost areas. In this context, this work aims to evaluate magnetic susceptibility, how to use tools to identify areas with different levels of use and quality of sugarcane and its use in the allocation of varieties. 445 ha were sampled with 1 point grid every 5 hectares and, following the understanding of the landscape, 14 points were selected for stratified sampling. Particle size and magnetic susceptibility of dimensions at depths of 0.0-0.2 m and 0.2-0.4 m were analyzed. Test data and raw material quality data were obtained through a 9-crop database and biometrics performed in the 2018/2019 crop. As a result, high correlation of clay and sand content with magnetic expression. By multivariate analysis of historical results, it is possible to organize 3 groups with different levels of use and quality, differentiating up to 17.28TCH or the result between the group with higher and lower potential, based on soil magnetic susceptibility. For biometrics results, as the classes of higher magnetic susceptibility observed in the largest difference and lowest sugar accumulation. Analyzing variety... (Complete abstract click electronic access below) / Mestre
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Germline Mutations in CHEK1 and CHEK2 in Women with Ovarian, Peritoneal, or Fallopian Tube CancerHarrell, Maria Isabel 01 January 2015 (has links)
Ovarian cancer is the deadliest gynecological malignancy affecting women. Diagnosis often occurs late due to non-specific symptoms, but if detected early, there is excellent chance for survival. One of the most important risk factors is family history. Up to 24% of cases are due to inherited loss-of-function mutations in genes involved in the DNA damage response. The theory underlying hereditary cancers is Knudson's two-hit theory of cancer causation, where two hits are necessary for cancer to occur in an individual: one in the germline and one in the tissue. The genes, CHEK1 and CHEK2, are modulators of the DNA damage response, and could be susceptible to a first hit. There is little to no evidence about whether loss-of-function mutations in either of these two genes can lead to ovarian cancer. Using a cohort of 587 ovarian cancer cases and 557 controls, this study sought to determine if CHEK1 and CHEK2 are associated with ovarian cancer. Applying Fisher's exact test to compare mutation rates and the t test to compare age at time of diagnosis, the alternative hypothesis about an association between disease and mutations in CHEK1 and CHEK2 was rejected, but an association between younger age at diagnosis in cases and mutations in either gene was confirmed. The association between age and mutations in either of these genes suggests that there is some influence of age on disease, but a clear association between development of disease and mutations cannot yet be established. This research has implications for social change: By recognizing the need to test earlier in women with mutations in CHEK1 and/or CHEK2, they will have a higher chance of survival and better health outcomes, not only for ovarian cancer but for related cancers as well.
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Coping Responses to Positive Genetic Suceptibility Test Results for Alzheimer's DiseaseNeverson, Diana Elaine 01 January 2015 (has links)
Genetic susceptibility test results have been found to cause differences in coping behavior following testing for the APOE-ε4 gene, associated with Alzheimer's disease. Coping behaviors differ within the first 12 months of testing. Currently, no studies have been conducted beyond the first 12 months comparing positive (P) and negative (N) groups or how sex relates to coping behavior based on positive test results. Based on the theory of primary and secondary control, and theory of stress, appraisal, and coping this study compared differences in coping strategies based on genetic test results and between sexes with positive test results beyond the first 12 months. Participants (n = 280) were selected who had undergone testing for the APOE-ε4 gene 12 or more months prior to the study and had a relative diagnosed with AD. Coping strategies were measured using the Brief COPE scale. Independent measures t test results were significant, indicating differences in coping between P and N groups. The P group reported significantly higher levels of cognitive and emotional coping strategies than did the N group 12 or more months after receiving test results. These findings were consistent with previous studies that produced significances in cognitive and emotional coping strategies between groups in the first 12 months. The findings were non significant for cognitive and emotional coping strategies for sex in the positive group. This study contributes to social change by informing impact decision making by individuals with positive test results for the APOE-ε4 gene in making financial changes, life styles changes, and family and work adjustments affecting their community and society.
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