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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.
131

Physical Activity, Cardiorespiratory Fitness and All-Cause Mortality

Larsen, Jorin Dane 26 April 2024 (has links) (PDF)
Introduction Both elevated levels of physical activity (PA) and high cardiorespiratory fitness (CRF) are associated with a decreased risk of all-cause mortality. The degree to which an individual's PA level and CRF status interact to influence mortality is not currently fully understood. This study investigated whether PA and CRF were independently related to all-cause mortality, and to what degree PA was associated with improved mortality risk in individuals with low CRF. Methods This is a prospective cohort study using health assessments on individuals gathered between 1975 and 2002. Health assessment data were matched with the National Death Registry to assess all-cause mortality. This study employed a self-reported measure of PA and Bruce protocol maximal treadmill to estimate CRF. Survival analyses were conducted using Cox proportional hazards regressions. Results Of 3,829 clients who were assessed, a total of 180 clients died within the follow-up period. The mean follow-up period was 25.4 ± 7 years. CRF was significantly and strongly related to all-cause mortality in a dose response manner. PA was not significantly related to all-cause mortality under a multivariable model. Discussion The primary finding was a strong inverse, dose response relationship between CRF and risk of all-cause mortality. This relationship further strengthens a large body of evidence suggesting that CRF may be a better predictor of all-cause mortality than an individual's self-reported PA. It is hypothesized that the apparent lack of relationship here observed between PA and all-cause mortality is largely due to the lack of specificity in the measure of PA employed, as well as the inaccuracy of self-report generally. Conclusion Physicians may benefit from employing objective measures of CRF in clinical settings instead of self-report-based measures of PA for the assessment of mortality risk. When studying the relationship between PA status and mortality, a more specific measure of PA than minutes of moderate to vigorous PA per week may be required. Further research should investigate the way in which PA is related to mortality in individuals with low CRF.
132

Evaluation of air fryer technology inactivation of Salmonella spp. in brownies formulated with almond flour and all-purpose flour

Glaspie, Courtlone Kenshon 10 May 2024 (has links) (PDF)
Flour has been identified as the source of Salmonella related recalls and outbreaks in past years. Flour is not usually heat treated and can cause issues when eaten raw, such as in the consumption of cookie dough and batters. Alternative flours like almond flour have been used in some bakery products. Alternative cooking techniques like air frying have increased as well due to their ease of use. The objective of this research was to study the effectiveness of air fryer technology on the inactivation of Salmonella in brownies formulated with all-purpose and almond flour. The aw and pH decreased significantly (p ≤ 0.05) over time within treatments, and there was no difference (p > 0.05) found across the two treatments. The brownie formulated with almond flour had a much higher fat content than that of the almond flour, but the all-purpose flour brownie had a much higher moisture content than that of the almond flour brownie. After 20 minutes of air frying at 176.7 °C, Salmonella counts were reduced in brownies formulated with all-purpose flour and almond flour by 5 log CFU/g and 6 log CFU/g, respectively. This study validated that air fryer technology is able to eliminate Salmonella in brownies formulated with all-purpose flour and almond flour when cooked for 20 minutes. This study assures that consumers can inactivate Salmonella in brownies formulated with all-purpose flour and almond flour when cooked for 20 minutes in an air fryer.
133

Constraining Explosion Physics and Progenitors of Transients via Statistical Inferencing of All Sky Survey Data Streams

Bhagya Madimugar Subrayan (18796561) 26 June 2024 (has links)
<p dir="ltr">Advancements in astronomical imaging all-sky surveys are revolutionising the field of time domain astronomy. However, the immense volume of alert data presents a critical bottleneck in maximizing scientific returns from these surveys. Effectively analyzing alert streams to discover transients in unexplored physical parameter spaces is crucial for enhancing scientific output. Building robust infrastructure to identify, prioritize, and execute efficient follow-up strategies on alert streams from all-sky surveys becomes critical. My thesis confronts this challenge through a multidisciplinary approach, by integrating statistical methods, machine learning algorithms, and hydrodynamical simulations to constrain transient explosion properties and motivate effective follow-up initiatives. </p><p dir="ltr">I analyze a sample of 45 Type II supernovae from the Zwicky Transient Facility (ZTF) public survey using a grid of hydrodynamical models in order to assess whether theoretically driven forecasts can intelligently guide follow-up observations supporting all-sky survey alert streams. I estimate several progenitor properties and explosion physics parameters, including zero-age main-sequence (ZAMS) mass, mass-loss rate, kinetic energy, <sup>56</sup>Ni mass synthesized, host extinction, and the time of the explosion. This work involves simulations of real-time of evolving incomplete light curves of the sample (∆t < 25 days, ∆t < 50 days, all data) leading to the conclusion that certain physical parameters exhibit greater reliability as indicators of true values during early epochs. This study emphasises the vital role of real-time modeling of transients, supported by multi-band synthetic light curves tailored to survey passbands, for identifying interesting transients based on their progenitor and explosion properties and determining critical epochs for follow-up observations.</p><p dir="ltr">In my thesis, I report multi wavelength observations and characterization of the ultraluminous transient AT 2021lwx (ZTF20abrbeie; aka“Barbie”) identified in the ZTF alert stream, that was flagged as an anomaly by the Recommender Engine For Intelligent Transient Track-ing (REFITT). From a spectroscopically measured redshift of 0.9945, and slowly fading g and r light curves spanning over 1000 observer-frame days that peak with an absolute magnitude of Mr = −25.7 mag, AT 2021lwx has an extraordinary peak pseudo-bolometric luminosity of log (Lmax/[erg/s]) = 45.7. The total radiative energy is over 10<sup>53</sup> erg, and as of today, the transient continues to decline slowly following a t<sup>−5/3</sup> power-law. Modeling available photometry with MOSFiT suggests that AT 2021lwx is a tidal disruption event (TDE) candidate involving a ≈ 14 or 15 solar mass star accreting onto a supermassive black hole (SMBH) with mass M<sub>BH</sub> ≈ 10<sup>8</sup> solar mass. But, intriguingly, no host galaxy associated with the theorized SMBH is detected yet. The Pan-STARRS non-detections do not definitively exclude the existence of a galaxy hosting AT 2021lwx. Utilizing EzGal, upper limits on the stellar mass for different stellar population models were determined. These upper limits suggest that a 10<sup>10</sup> solar mass host galaxy cannot be ruled out.</p><p dir="ltr">The enhanced sensitivity of upcoming large-scale all-sky surveys enables the early detection of transients, providing unique insights into their progenitor systems, an example being detection of shock cooling emission (SCE) in light curves of stripped-envelope supernovae(SESNe). Leveraging a statistically significant sample of these events with early detections from all-sky surveys presents an invaluable opportunity to constrain their environments, pro-genitors, and explosion properties. In my final study contributing to this thesis, I analyze a sample of 16 SESNe identified from the ZTF survey, characterised by prominent shock cooling emission features in their light curves. By modeling the SCE and the radioactive peak in these transients, I derive estimates of progenitor radius, mass of the extended envelope and explosion properties of SESNe. This analysis yields upper limits and ranges for the compactness and envelope structures of the SESN progenitors that exhibit SCE in their light curves. I conclude my thesis with a summary of the findings and their future applications.</p>
134

Instituições internacionais e educação: a agenda do Banco Mundial e do Education for All no caso brasileiro / International Institutions and Education: the World Bank and Education for All agenda in the brazilian case

Bernussi, Mariana Medeiros 12 August 2014 (has links)
A dissertação pretende explorar a agenda da educação nas relações internacionais por meio do papel das organizações internacionais. Inseridos em uma realidade multilateral, organismos como a UNESCO, a UNICEF, o PNUD, a OCDE, a OIT e o Banco Mundial ganham cada vez mais espaço na arena internacional para discutir educação, alargando as fronteiras da ação política educacional para além do âmbito nacional. O objetivo desse trabalho é traçar um panorama histórico do entendimento destas organizações internacionais sobre o tema da educação, além de identificar qual das agências é protagonista na definição de projetos e programas educacionais. Perante a ascensão do Banco Mundial com o mandato da educação, confirmada por sua liderança na iniciativa Education for All, ainda pretende-se realizar um estudo de caso sobre as propostas do Banco Mundial na educação brasileira. A dissertação está dividida em dois artigos. O primeiro consiste em uma análise da educação de acordo com a percepção que as organizações internacionais possuem do tema, com foco na UNESCO e no Banco Mundial. O segundo artigo investiga os projetos do Banco Mundial desenvolvidos para o Brasil a partir de 1990. A finalidade do estudo é analisar de que forma os objetivos do Education for All estão presentes nesses projetos e se eles contribuem para uma mudança nas regulações, práticas e prioridades nacionais, e de que forma. / The dissertation has the purpose to explore the agenda of education in international relations through the role of international organizations. Inserted in a multilateral reality, organizations such as UNESCO, UNICEF, UNDP, OECD, ILO and the World Bank are gaining more space in international arena to discussing education, broadening the boundaries of educational policy-making beyond the national level. The aim of this study is to chart a historical overview of the understanding that these international organizations have about the topic of education, and identify which agency is the protagonist in the definition of the educational projects and programs. Given the rise of the World Bank, with the mandate of education, confirmed by its leadership in the Education for All initiative, the text also intends to conduct a case study on the proposals of the World Bank for Brazilian education. The dissertation is divided into two papers. The first one consists of an analysis of education according to the perception that international organizations, focusing on UNESCO and the World Bank. The second article investigates the Bank projects developed in Brazil since 1990. The purpose of the study is to examine how the goals of Education for All are present in these projects and if they contribute to a change in national regulations, practices and priorities, and how.
135

PROVOZNÍ OVĚŘENÍ MONOSEXNÍCH OBSÁDEK V CHOVU TRŽNÍHO KEŘÍČKOVCE JIHOAFRICKÉHO (Clarias gariepinus)

JELÍNEK, Jaroslav January 2018 (has links)
The objective of the present diploma thesis was to verify the influence of monosex populations in African catfish (Clarias gariepinus) fishfarming on growth rate, growth heterogeneity, feed conversion ratio, yield and product quality in the operating conditions of a small fish farm with a recirculating aquaculture system. In six tanks with a volume of 0,3 m-3, 60 individuals with an average unit weight of 614 ? 135 g, all-male, all-female and mixed- sex (in 2 repeats each) were deployed. The fish were fed with feed in the usual and registered feed doses 4 times a day. At the end of the experiment, 119 days average fish weight reached 1445 ? 911 g. The composition of the populations was found to have a statistically significant effect on the food conversion ratio, gonadosomal index, and fillet yield. Statistically significant differences were not found in specific growth ratio (SGR), growth heterogeneity, or muscle composition (fat and protein content). The yield of fillets without skin reached only 40.74 ? 1.81% for all-female group. An economically advantageous alternative to a mixed -sex groupe with a sex ratio of 1: 1 was a all-male fishfarning groupe where the yield of skinless fillets was 46.99 ? 1.12%. Food conversions were also more favorable for all-male groups (FCR = 1.08 ? 0.08 and 1.04 ? 0.12) compared to all-female (FCR = 1.18 ? 0.21 and 1.25 ? 0.19 ). The fat content of the muscle at the end of the experiment varied between 5.10-10.53% for each group without proven dependence on the type of the group, the protein content showed only minimal differences, varied between 15.18 and 16.46%, dry mass contained muscle from 24.23 to 27.95% without proven dependence on the type of occupancy. Significant economic impact has the composition of groups when evaluating the yield of fillets without skin as the final product.
136

Optical solitons in quadratic nonlinear media and applications to all-optical switching and routing devices

Santos Blanco, María Concepción 02 March 1998 (has links)
Esta tesis constituye un estudio detallado y exhaustivo de las propiedades de una variedad específica de ondas ópticas solitarias. Observadas experimentalmente por primera vez en 1995, estas ondas estan formadas por un haz óptico a frecuencia fundamental y su segundo armónico que están ligados entre sí y viajan juntos en el material cuadrático; y son debidas al equilibrio entre la difracción lineal que sufre el haz al propagarse y un término no lineal de segundo orden en la susceptibilidad del medio. Las llamamos por eso solitones ópticos en medios cuadráticos o simplemente 'solitones cuadráticos'. También se les conoce como 'Solitones Multicolor' aludiendo al hecho de que requieren de haces a diferentes frecuencias para formarse.Un medio no-lineal cuadrático tiene por fuerza que ser no-centrosimétrico, lo cual es una variedad de anisotropía. Una gran parte de los materiales no-lineales cuadráticos (los que tienen mayor interés para la industria) son uniaxiales lo que significa que presentan un eje de simetría que suele llamarse eje óptico. De la dirección de un haz relativa a ese eje óptico dependen las características de la propagación del haz en el medio cuadrático no-lineal. Una consecuencia de eso en configuraciones de interés es un desvío ('walk-off') sufrido por el haz respecto a su dirección de propagación inicial al entrar en el material no-lineal.Las propiedades de los solitones cuadráticos 'caminantes' son también estudiadas en la tesis, estableciendo que existe una relación entre la potencia inyectada en el medio y el ángulo de desvío (walking angle).Una parte importante de la tesis está dedicada al estudio a través de exhaustivos experimentos numéricos del potencial de estas ondas solitarias para constituir la base de dispositivos de conmutación y encaminamiento totalmente ópticos que puedan hacer realidad la promesa de la red transparente totalmente óptica. Los experimentos han permitido identificar varias configuraciones de interés con niveles de potencia y dimensiones que permiten plantearse el diseño y construcción de dispositivos comerciales de conmutación y encaminamiento totalmente ópticos basados en solitones ópticos cuadráticos. / This thesis is a comprehensive study of the fundamental properties of a specific kind of optical spatial solitary waves. First observed experimentally in 1995, these solitary waves are formed by an optical beam at a fundamental frequency and its second harmonic which propagate together and are mutually entangled; and are due to a balanced interplay between the beams' linear diffraction and a second-order nonlinear susceptibility of the medium. They are thereby referred as 'Optical Solitons in Quadratic Nonlinear Media' or simply 'Quadratic Solitons', They are also known as 'Multicolor Solitons' recalling that they are formed by beams at different frequencies.A quadratic nonlinear media needs to be non centrosymmetric which is a special kind of anisotropy. A great deal of quadratic nonlinear materials (the most used by industry such as lithim niobate, KTP, etc.) are uniaxial meaning that they feature a symmetry axis known as 'optical axis'. The direction of propagation of an optical beam relative to that axis determines the characteristics of the beam's propagation through the quadratic nonlinear material. A main result of that in some configurations of interest is a walk-off suffered by the beam as it enters the quadratic material.The properties of the families of quadratic solitons in the presence of a linear walk-off (quadratic walking solitons) are studied as well in the thesis stating that there is a relationship between the power injected into the medium and the walking angle, suitable to applications of all-optical switching and routing.An important last part of the thesis is devoted to the study from a practical viewpoint and through extensive numerical experiments of the potential of these solitary waves as the basis of practical all-optical switches and routers which could take the all-optical transparent network to a reality. The experiments have allowed to identify several configurations of interest with power level and dimensions suited to practical applications which could allow the production of commercial all-optical switching and routing devices based on quadratic solitons.
137

Routing algorithms for large scale wireless sensor networks

Nittala Venkata, Lakshmana Prasanth 17 February 2005 (has links)
Routing in sensor networks is a challenging issue due to inherent constraints such as power, memory, and CPU processing capabilities. In this thesis, we assume an All to All communication mode in an N × N grid sensor network. We explore routing algorithms which load balance the network without compromising the shortest paths constrain. We analyzed the Servetto method and studied two routing strategies, namely Horizontal-Vertical routing and Zigzag routing. The problem is divided into two scenarios, one being the static case (without failed nodes), and the other being the dynamic case (with failed nodes). In static network case, we derived mathematical formulae representing the maximum and minimum loads on a sensor grid, when specific routing strategies are employed. We show improvement in performance in load balancing of the grid by using Horizontal-Vertical method instead of the existing Servetto method. In the dynamic network scenario, we compare the performance of routing strategies with respect to probability of failure of nodes in the grid network. We derived the formulae for the success-ratio, in specific strategies, when nodes fail with a probability of p in a predefined source-destination pair communication. We show that the Servetto method does not perform well in both scenarios. In addition, Hybrid strategy proposed does not perform well compared to the studied strategies. We support the derived formulae and the performance of the routing strategies with extensive simulations.
138

Síntese e caracterização de ácido-all-trans-retinoico incorporado a nanofibras poliméricas e seus efeitos sobre células de osteossarcoma / Sintesis and characterization of all-trans-retioic-acid incorporated to polymers Nanofibers under human osteossarcoma cells

Girondi, Camila Miorelli 02 May 2018 (has links)
Submitted by Camila Girondi (camila.girondi@gmail.com) on 2018-07-03T20:30:17Z No. of bitstreams: 1 Dissertação 28.06 COM FICHA CATALOGRÀFICA.pdf: 1652288 bytes, checksum: 2ff0f9722f6563cc30aaacbdd2bd4b81 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-07-10T19:06:46Z (GMT) No. of bitstreams: 1 girondi_cm_me_sjc.pdf: 1652288 bytes, checksum: 2ff0f9722f6563cc30aaacbdd2bd4b81 (MD5) / Made available in DSpace on 2018-07-10T19:06:46Z (GMT). No. of bitstreams: 1 girondi_cm_me_sjc.pdf: 1652288 bytes, checksum: 2ff0f9722f6563cc30aaacbdd2bd4b81 (MD5) Previous issue date: 2018-05-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As nanofibras (NF) podem ser sintetizadas por meio de eletrofiação, um método simples que permite incorporação de fármacos em biopolímeros que apresentam a vantagem de serem liberados de forma gradual. Policaprolactona (PCL) apresenta a vantagem de poder ser eletrofiada permitindo a incorporação de fármacos. Os ácidos retinoicos são fármacos empregados no tratamento de osteossarcoma, mas, apresentam efeitos colaterais. O ATRA (all-trans-retinoic-acid) é o mais comum entre os retinoides. Os objetivos deste estudo foram: sintetizar e caracterizar NF, incorporar o fármaco a elas e verificar a liberação ao meio de cultura; realizar testes de citoxicidade e genotoxicidade tais como: crescimento, integridade, viabilidade e micronúcleo de células MG63 tratadas com NF incorporada com ATRA e analisar a secreção das citocinas pró inflamatórias: IL-1β, IL-6 e TNF-α por meio do teste ELISA. As NF sintetizadas por meio da eletrofiação foram caracterizadas morfologicamente e bioquimicamente por meio de microscopia eletrônica de varredura (MEV) e estudo do espectro de infravermelho da transformada de Fourrier (FTIR): Os testes in vitro foram realizados utilizando uma linhagem de células imortalizadas de osteossarcoma, MG63. Os ensaios incluídos nesse estudo foram divididos em grupos compostos por: [C (controle puro), ATRA (controle positivo), NF (controle negativo) e NF + ATRA (grupo experimental).] Em todos os grupos foram realizados testes de viabilidade celular (MTT), micronúcleo e ELISA sob os tempos de 3, 7 e 14 dias. A liberação do fármaco através do sistema de NF+ATRA foi comprovada pelo FTIR. Os demais resultados encontrados foram avaliados através do teste ANOVA one-way, no qual o método apresentou-se eficiente, mostrando diferença estatística de p=0,00, sendo signficante para todos os períodos de tempo nos testes de MTT e MN, além de ser verificada a secreção de citocinas proinflamatórias IL-1β e IL-6, comprovando os efeitos citotóxicos e genotoxicos sob células MG63 mostrando a efetividade da técnica. Podendo ser uma alternativa para o tratamento. / Nanofibers (NF) can be synthesized by electro-spinning, a simple method that allows incorporation of drugs into biopolymers that have the advantage of being released gradually. Polycaprolactone (PCL) has the advantage that it can be electrophied allowing the incorporation of drugs. Retinoic acids are drugs used in the treatment of osteosarcoma, but have side effects. ATRA (all-trans-retinoicacid) is the most common retinoid. The objectives of this study were: to synthesize and characterize NF, to incorporate the drug to them and to verify the release to the culture medium; perform cytotoxicity and genotoxicity tests such as: growth, integrity, viability and micronucleus of N63-treated NF-treated cells with ATRA and to analyze the secretion of pro-inflammatory cytokines: IL-1β, IL-6 and TNFα by the ELISA . The NF synthesized by electrophilation were characterized morphologically and biochemically by scanning electron microscopy (SEM) and Fourrier Transform Infrared Spectrum (FTIR) study: In vitro tests were performed using an immortalized osteosarcoma cell line, MG63. The trials included in this study were divided into groups composed of: C (pure control), ATRA (positive control), NF (negative control) and NF + ATRA (experimental group). All groups were tested for cell viability (MTT), micronucleus and ELISA under the times of 3, 7 and 14 days. Release of the drug through the NF + ATRA system was confirmed by FTIR. The other results were evaluated using the oneway ANOVA test, in which the method was efficient, showing a statistical difference of p = 0.00, being significant for all time periods in the MTT and MN tests, besides the secretion of proinflammatory cytokines IL-1β and IL-6, proving the cytotoxic and genotoxic effects under MG63 cells, showing the effectiveness of the technique. It may be an alternative to treatment
139

Influência da hipóxia na determinação da potência crítica pelo teste de 3 minutos máximo / impact of hypoxia on determination of critical power by tree minuts all-ou test

Santos, Rafael Penteado dos 31 July 2014 (has links)
Made available in DSpace on 2016-12-06T17:07:02Z (GMT). No. of bitstreams: 1 Rafael Penteado.pdf: 1084171 bytes, checksum: 1fe7da89a2a7add8f27869b51f7e52d5 (MD5) Previous issue date: 2014-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introduction: Critical Power (CP) is the maximum rate can be maintained in a stable metabolic state muscle work. In the search for a test associated with less error and greater practical application, a series of studies investigating the validity of a single maximal test "all-out" to determine the PC. This test was designed with the assumption that, by inducing the depletion of anaerobic reservations as early as possible, the aerobic system predominantly assume the replenishment of ATP and consequently the amount of work done in this situation will be the next PC. Thus this study aims to explore the impact of hypoxia (FiO2 = 0,13), in determining the PC by 3-MT test. Methods: 8 healthy university students were evaluated (7 men and 1 woman). Incremental ramp test for determination of the maximal and submaximal parameters as well as the braking factor (power +50% &#916; /pacing2 ) test three minutes to determine the maximum EP and W` in normoxia and hypoxia (Fi O2 = 0.13) conditions, constant load tests at 100% of EP determined in three minutes maximum. Student t test for the measurements between tests. Results: The main hypothesis of the study was not accepted since the addition of hypoxia did not cause enough stress to the point of changing the anaerobic contribution and interfere with the determination of EP (3-MTHYP = 213±43W, 3-MTNOR = 217±49 Wp = 0.35). There was no significant difference during the constant load tests at 100% of EP (EP 3-MTHYP = 23.95±8 min, EP-3 MTNOR = 19.41±10 min p = 0.36). Conclusion: Adding hypoxia (Fi O2 = 0.13) was not able to change the energy contribution to the point of changing the parameter EP aerobic and anaerobic W `, highlighting the robustness of the model against this intervention. Still, the responses associated with RPE during constant-load test are close to those encountered during constant load tests on PC. Further investigations with different levels of hypoxia are necessary for more conclusive answers. / Introdução: Potência crítica (PC) representa a máxima taxa de trabalho muscular possível de ser mantida em um estado estável metabólico. Na busca por um teste com menor erro associado e maior aplicação prática, uma série de trabalhos vem investigando a validade de um único teste máximo all-out para determinar a PC. Este teste foi concebido com o pressuposto de que, induzindo o esgotamento das reservas anaeróbias o quanto antes possível, o sistema aeróbio assumiria predominantemente a reposição de ATP e consequentemente a carga de trabalho realizada nessa situação será próxima a PC. Assim este estudo, tem como objetivo explorar o impacto da hipóxia (i.e. FiO2 0.13), na determinação da PC pelo teste máximo de três minutos (3-MT). Métodos: Oito universitários saudáveis foram avaliados (7 homens e 1 mulher). Teste incremental de rampa foi utilizado para determinação dos parâmetros máximos e submáximo bem como do fator de frenagem (potencia+50%&#8710; / cadendia2). Teste de 3-MT para determinação do EP e W` nas condições normoxia e hipóxia (Fi O2=0,13). Testes de carga constante a 100% dos EP foram utilizados para verificação das respostas fisiológicas. O teste t de student foi utilizado para as aferições entre os testes. Resultados: A hipótese principal do estudo não foi aceita, uma vez que a adição de hipóxia não gerou estresse suficiente ao ponto de alterar a contribuição anaeróbia e interferir na determinação do EP (3-MTHYP = 213±43W, 3-MTNOR = 217±49W p=0,35) . Também não houve diferença significativa durante os testes de carga constante a 100% dos EP determinados (EP 3-MTHYP = 23,95±8 min., EP 3-MTnor = 19,41±10 min. p= 0,36). Conclusão: A adição de hipóxia (Fi O2=0,13) não foi capaz de alterar a contribuição energética a ponto de alterar o parâmetro aeróbio EP, e anaeróbio W`, destacando a robustez do modelo frente a essa intervenção. Ainda, as respostas associadas ao EP durante o teste de carga constante estão próximas aquelas encontradas durante testes de carga constante na PC. Futuras investigações com diferentes níveis de hipóxia são necessárias para obter respostas mais conclusivas.
140

Retinol, ácido retinóico e seus receptores e o índice de proliferação celular e de apoptose no lobo dorsolateral da próstata de ratos adultos UCh (bebedores voluntários de etanol a 10%) / Retinol, retinoic acid and its receptors and the rate of cell proliferation/apoptosis in the dorsolateral prostate lobe of adult UCh rats (10% (v/v) ethanol voluntary drinkers)

Fontanelli, Beatriz Aparecida Fioruci, 1985- 18 August 2018 (has links)
Orientador: Francisco Eduardo Martinez / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-18T07:43:37Z (GMT). No. of bitstreams: 1 Fontanelli_BeatrizAparecidaFioruci_M.pdf: 2160007 bytes, checksum: 5e358e9b41de70f7fd7c801fae0e0378 (MD5) Previous issue date: 2011 / Resumo: A exposição ao etanol altera a concentração do retinol e do all-trans-ácido retinóico (atAR) em vários tecidos. Os retinóides, retinol e atAR, são importantes para a diferenciação e manutenção das células epiteliais da próstata. O atAR se liga aos receptores de ácido retinóico (RARa, ß e y) e a interação receptor/ligante com a sequência responsiva ao retinóide no DNA, levam à transcrição de genes alvos. Assim, o atAR exerce efeitos no crescimento celular, diferenciação e apoptose, sendo essencial no desenvolvimento e diferenciação de órgãos e tecidos. Nosso objetivo foi analisar o retinol, o ácido retinóico e seus receptores, bem como, o índice de proliferação celular e de apoptose no lobo dorsolateral da próstata de ratos adultos UCh. Os animais foram divididos em quatro grupos experimentais (n=10/grupo): UChA (ingestão voluntária de etanol a 10% (v/v); UChACo (controle - ausência de etanol); UChB (ingestão voluntária de etanol a 10% (v/v) e UChBCo (controle - ausência de etanol). Após 150 dias de experimentação, os animais foram eutanasiados por decapitação e o sangue do tronco e os lobos dorsolaterais das próstatas foram coletados e processados: (1) para análises da concentração do retinol e do atAR no plasma e na próstata por meio de HPLC; (2) e análises de microscopia de luz para a proliferação celular (Ki-67), apoptose (Tunel) e para os receptores de ácido retinóico, por meio dos anticorpos anti-RARa, -ß e -y. O consumo crônico de etanol diminuiu a concentração do retinol no plasma dos grupos UChB (consumo alto de etanol) e UChA (consumo baixo de etanol). A concentração do retinol foi ainda menor no plasma do grupo UChB comparado ao UChA. No entanto, a concentração do retinol no tecido prostático não teve diferença significativa entre os grupos. O atAR aumentou significativamente somente no plasma do grupo UChB. Na próstata, a concentração do atAR aumentou no grupo UChB, enquanto que no UChA não houve diferença estatística. O RAR? na próstata dorsal e lateral dos ratos UCh não foi alterada em função do consumo de etanol. Já os RARß e -? apresentaram aumento do sinal na próstata dorsal do grupo UChB. Não houve diferença no índice de proliferação celular e de apoptose nas próstatas dorsais e laterais dos grupos experimentais. Conclui-se que o etanol altera a concentração do retinol e do atAR no plasma. Essa alteração é diretamente proporcional à quantidade de etanol consumida. Já na próstata, o retinol não é alterado pelo etanol. O consumo alto de etanol altera a concentração do atAR na próstata dorsolateral e a expressão dos RAR ß e y na próstata dorsal. A alteração da expressão dos RAR pode aumentar a sensibilidade da próstata à ação do atAR. O etanol não altera a proliferação celular e a apoptose na próstata dorsal e lateral / Abstract: Ethanol exposure alters the concentration of retinol and all-trans retinoic acid (atAR) in several tissues. Retinoids (retinol and atAR) are essential for the differentiation and homeostasis of the prostate epithelial cells. atAR binds to retinoic acid receptors (RAR a, ß and ?) and the interaction receptor/ligand with the sequence responsive to retinoid into DNA lead to transactivation of target genes. Thus, atAR directly produces their effects on cell growth, differentiation and apoptosis. This study aimed to analyze the retinol and all-trans-retinoic acid concentrations and its atAR receptors as well as the cell proliferation and apoptosis index upon the dorsolateral prostate lobe of adult UCh rats. All animals were divided into four experimental groups (n = 10/group): UChA (10% ethanol (v / v) voluntary intake); UChACo (without ethanol consumption); UChB (10% ethanol (v / v) voluntary intake) and UChBCo (without ethanol consumption). After 150 days of experimentation, animals were sacrificed followed by decapitation and trunk blood and dorsolateral prostate lobes collected. Samples of plasma and prostate by concentration analysis of the retinol and atAR were processed for HPLC. The cell proliferation and apoptosis immunoreactivities were assessed by Ki-67 and Tunel, respectively, and nuclear receptors by anti-RAR a,-ß and-y. Chronic ethanol consumption reduced the concentration of plasma retinol in UChB (high ethanol intake) and UChA groups (low ethanol intake). The retinol concentration in plasma was even lower in UChB compared to UChA group. However, the retinol concentration in prostate tissue was not significantly different between the groups. Concentration of atAR increased in plasma of UChB group, and was 96% higher in the UChA group. The prostate, atAR increased in the UChB group, while in UChA group no statistical difference. There was no statistical difference in proliferation cell and apoptosis in the dorsal and lateral prostate lobes between the groups. The expression of RAR a in the dorsal and lateral prostate of UCh rats was not altered as a function of ethanol consumption. Already RAR ß and-y showed increased signal in the dorsal prostate UChB group. We conclude that ethanol alters the concentration of retinol and atAR in plasma. This change is directly proportional to the amount of ethanol consumed. In the prostate, retinol is not altered by ethanol. The high ethanol intake alters the concentration of atAR in dorsolateral prostate and the expression of RARß and RARy in the dorsal prostate. Alteration in expression of RAR can increase sensitivity to the action of the atAR in prostate. Ethanol does not alter cell proliferation and apoptosis in the dorsolateral prostate / Mestrado / Anatomia / Mestre em Biologia Celular e Estrutural

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