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Envolvimento da serotonina no controle respiratório durante o desenvolvimento pós-natal
(Universidade Federal de São Carlos, 2017-04-07) Rossato, Vivian Biancardi; Funk, Gregory Douglas; https://lattes.cnpq.br/5940547908075562; Batalhão, Luciane Helena Gargaglioni; https://lattes.cnpq.br/5850453468994497; https://lattes.cnpq.br/3835317718066631
Serotonin (5-HT) is a neurotransmitter involved in nervous system development, being an important modulator of respiratory rhythm via activation of diverse receptors on respiratory neurons. Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine act as antidepressants and are generally prescribed in depression therapy, including to pregnant women. This study investigated the effects of prenatal (E15-21) exposure to fluoxetine on the ventilatory and metabolic responses to 7% CO2 (hypercapnia) and 10% O2 (hypoxia) of male and female rats during postnatal development (P0-82). To this end, osmotic pumps were implanted subcutaneously in pregnant female rats at embryonic day (E) 15 and delivered vehicle (VEH) or fluoxetine (SSRI, 10 mg/Kg/day) during 7 days. Respiratory frequency (fR), tidal volume (Vt), ventilation (Ve ), O2 consumption (''VO2 ) and air convection requirements (Ve/VO2 ratio) of pups from these litters were studied. In P0-2 male rats, the SSRI group showed a lower Vt and a higher fR in room air conditions, whereas female rats of SSRI group showed a lower Vt in normocapnia normoxica and a higher hyperventilation induced by hypercapnia. At P6-8, male SSRI animals presented a higher fR during hypoxia together with a decrease in the number of neurons that express 5-HT in the caudal dorsal raphe (RDC). P6-8 females from ISRS group showed an attenuated fR during hypoxia. No differences were observed between male rats in the VEH and ISRS groups at P12-14 although there was an increase in the number of 5-HT neurons in the RD. SSRI females showed an attenuated hypercapnic ventilatory response. At P24-26, male SSRI animals showed a lower VEin room air conditions, a higher ventilatory response to hypercapnia and to hypoxia, together with an increase in the number of 5-HT neurons in the ROB and a higher density of TH expression in the LC area. P24-26 SSRI females displayed a lower Ve/V O2 due to a higher V O2 in room air conditions and a higher hyperventilation induced by hypercapnia. In P76-82 male rats, the SSRI group hypoventilated in room air conditions during both wakefulness and NREM sleep and showed a higher increase in Vt induced by hypoxia during wakefulness. These animals showed a higher number of 5-HT neurons in the ROB, RPA and an increase in the number of neurons that express TH in the A5 and in the LC rostral area. Finally, at P76-82, female SSRI rats showed a higher fR in room air conditions during both wakefulness and NREM sleep, an attenuated hypercapnic ventilatory response due to an attenuation of fR during NREM sleep; and an attenuated hypoxic ventilatory response during wakefulness. Also, these animals showed a decrease in the number of 5-HT neurons in the RD. Taken together, these data indicate that SSRI exposure during the prenatal period alters the development of the brainstem respiratory network and results in long lasting and sex specific changes in breathing pattern and in the ventilatory responses to respiratory challenges demonstrating that central and/or peripheric chemoreception may be disrupted in these animals.
Degradation modeling for reliability analysis with time-dependent structure based on the inverse gaussian distribution
(Universidade Federal de São Carlos, 2017-04-07) Morita, Lia Hanna Martins; Tomazella, Vera Lucia Damasceno; https://lattes.cnpq.br/8870556978317000; https://lattes.cnpq.br/8952048121396398
Conventional reliability analysis techniques are focused on the occurrence of failures over time. However, in certain situations where the occurrence of failures is tiny or almost null, the estimation of the quantities that describe the failure process is compromised. In this context the degradation models were developed, which have as experimental data not the failure, but some quality characteristic attached to it. Degradation analysis can provide information about the components lifetime distribution without actually observing failures. In this thesis we proposed different methodologies for degradation data based on the inverse Gaussian distribution. Initially, we introduced the inverse Gaussian deterioration rate model for degradation data and a study of its asymptotic properties with simulated data. We then proposed an inverse Gaussian process model with frailty as a feasible tool to explore the influence of unobserved covariates, and a comparative study with the traditional inverse Gaussian process based on simulated data was made. We also presented a mixture inverse Gaussian process model in burn-in tests, whose main interest is to determine the burn-in time and the optimal cutoff point that screen out the weak units from the normal ones in a production row, and a misspecification study was carried out with the Wiener and gamma processes. Finally, we considered a more flexible model with a set of cutoff points, wherein the misclassification probabilities are obtained by the exact method with the bivariate inverse Gaussian distribution or an approximate method based on copula theory. The application of the methodology was based on three real datasets in the literature: the degradation of LASER components, locomotive wheels and cracks in metals.
Regressão binária usando ligações potência e reversa de potência
(Universidade Federal de São Carlos, 2017-04-07) Anyosa, Susan Alicia Chumbimune; Bazán Guzmán, Jorge Luis; https://lattes.cnpq.br/7302778157579178; https://lattes.cnpq.br/9217843169672401
The aim of this dissertation is to study a family of asymmetric link functions for binary regression models under Bayesian approach. Specifically, we present the estimation of parameters of power and reversal power binary regression models considering Hamiltonian Monte Carlo method, on No-U-Turn Sampler extension, and Metropolis-Hastings within Gibbs sampling method. Furthermore, we study a wide variety of model comparison measures, including information criteria and measures of predictive evaluation. A simulation study was conducted in order to research accuracy and efficiency on estimated parameters. Through analysis of educational data we show that models using the proposed link functions perform better fit than models using standard links.
Análise das relações entre práticas de melhoria contínua e desempenho percebido na inovação de produtos e processos
(Universidade Federal de São Carlos, 2017-04-07) Gonçalves, Celso Luiz; Lizarelli, Fabiane Letícia; https://lattes.cnpq.br/4525431419326559; Toledo, José Carlos de; https://lattes.cnpq.br/9421627326330417; https://lattes.cnpq.br/4480240529751230
The practices of Continuous Improvement (CI) and the Innovation of products and processes get competitive advantage for organizations, in relation to competitors, whether in positioning by low cost or differentiation strategy. These practices need to be managed and integrated in order to ensure, in the long run, the desired results. Although seen as significant for the strategic goals of the organization, often are managed independently and with different goals. There is little consensus in the literature if the use of Continuous Improvement Practices has positive or negative impact on the processes and outcomes of Innovation in firm. However, are observed recurring statements about the necessity of coexistence and integration of CI programs and Practices and Innovation. There is interest in examining what existing relations in the context of organizations that make it possible to identify whether a greater intensity of use of CI practices influences the perceived performance in innovation of products and processes. In order to analyze the possible relations, the study was conducted by survey on a sample of 102 companies of Auto parts, Pharmaceuticals, Electric-Electronics appliances the State of São Paulo in Brazil. The sample data were analyzed by descriptive and multivariate statistical methods (cluster analysis). The descriptive analysis showed significant evidence on integration relations between CI and Product and process innovation, as well as, the IC contribution in creating a fertile environment for Innovation. Multivariate analyzes revealed existence of associations between the intensity of use of IC practices and perceived performance in Innovation, mainly in processes. The findings contribute to a better understanding of the topic and management application in organizations, besides indicating opportunities for further studies.
A abordagem de martingais para o estudo de ocorrência de palavras em ensaios independentes
(Universidade Federal de São Carlos, 2017-04-07) Masitéli, Vanessa; Gava, Renato Jacob; https://lattes.cnpq.br/0494315910583969; https://lattes.cnpq.br/2570625768458153
Let {Xn} be a sequence of i.i.d. random variables taking values in an enumerable alphabet. Given a finite collection of words, we observe this sequence till the moment T at which one of these words appears as a run. In this work we apply the martingale approach introduced by Li (1980) and Gerber e Li (1981) in order to study the waiting time until one of the words occurs for the first time, the mean of T and the probability of a word to be the first one to appear.
Catalisadores de Au suportados aplicados à oxidação preferencial do CO : influência da interação entre Au e Fe nos sítios ativos
(Universidade Federal de São Carlos, 2017-04-07) Franke, Karen Niége; Ferreira Palhares, Adriana Paula; https://lattes.cnpq.br/5736423072715628; https://lattes.cnpq.br/3572389539600848
New sources of clean energy have been studied, such as hydrogen (H2). Carbon monoxide, a subproduct of its production, poisons the fuel cell. To reach concentrations below 10 ppm, the addition of preferential CO oxidation reaction (PROX-CO) is required. This work is based on the study of behavior of gold and iron catalysts for PROX-CO. Studies point to high activity and good selectivity in PROX-CO with the combination of Au and Fe in catalysts, especially at low temperatures, although there are effects of the iron-gold interaction to be clarified. M. Haruta, H. Kung and I. Green have proposed mechanisms of reaction where the support plays an important role in PROX-CO, either by its O2 vacancies at the interface with the Au NPs or by taking part in the adsorption of CO molecules. Iron oxides become interesting as they are known for their oxygen vacancies and have high oxygen mobility in their network that varies according to the phase of this metal oxide. Results with Au and/or Fe catalysts supported on γ-Al2O3 showed that varying the synthesis, interaction and oxidation state of Au and Fe were modified. Catalysis tests for PROX-CO with previously reduced samples were more active possibly due to the formation of Au+/Au0 ions essentials for the activation and oxidation of CO. AuFeAl sample reduced at 400°C was shown to be most promising for PROX-CO of the samples tested, due both conversion and selectivity. Subsequently, gold catalysts were supported in the phases hematite, goethite and magnetite of iron oxide obtained from different preparation methods with different thermal treatments. These catalysts presented very different performance for PROX-CO. The performance for hematite-supported Au catalysts was higher. The AuHSG catalyst, which at around 110°C, showed a 33% CO conversion with acceptable CO2 selectivity (above 1:1 CO and O2 conversions respectively).