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Histamina facilita a aprendizagem em uma tarefa de escolha espacial em Carassius auratus
(Universidade Federal de São Carlos, 2006-03-03) Santos, Fernanda Romaguera Pereira dos; Mattioli, Rosana; https://lattes.cnpq.br/5694498670428619
This work intended to investigate in forebrain ablated Carassius auratus the effect of the H1 receptor blockade in a spatial choice task using a T-maze test with positive reinforcement. Sixty-nine goldfish were submitted to surgery for removal of both telencephalic lobes five days before the beginning of the experiment. A T-shaped glass aquarium, which had two feeders located at the extremities of the long arm, was employed. One of the two feeders was blocked. The experimental trials were performed in nine consecutive days. Each fish was individually placed in the short arm and confined there for thirty seconds, then it was allowed to swim through the aquarium to search for the food for ten minutes (maximum period). Time to find food was analysed in seconds. Animals were injected intraperitoneally with chlorpheniramine (CPA) at 16 mg/kg of body weight or saline after every trial, ten minutes after it had been replaced at house aquarium. Data were analyzed via a three-way analysis of variance (ANOVA) with repeated measures, and post hoc comparisons were analyzed using the Student Newman-Keuls test (p<0.05). All the training latencies of A-SAL group were significantly higher than latencies of S-SAL group (p<0.05). S-SAL group showed a significative decrease in latencies at the second trial and maintained that reduction until the end of the experiment (p<0.05), S-CPA group demonstrated a decrease only after the fourth trial (p<0.01), A-SAL group showed reduced latencies after the fifth trial (p<0.05), and ACPA group did not showed any difference between training latencies. Thus, our results showed that CPA seems to impair the consolidation of memory either on telencephalon ablated animals and in sham-operated ones. Furthermore, this work supports evidence that histamine plays a facilitatory role in learning and memory processes of a spatial task through its action in primitive structures of the brain in teleost fish.
O conceito de n-varifold e EDP
(Universidade Federal de São Carlos, 2006-03-03) Paula, Fernanda Gonçalves de; Nascimento, Arnaldo Simal do; https://lattes.cnpq.br/6609243657130387
The goal of this work is the detailed study of some topics of Geometric Measure Theory, giving special attention to the n-varifold concept and illustrating its use in the asymptotic behavior of critical points of the energy functional for the van der Waals-Cahn-Hilliard theory of phase transitions.
Germes de funções sobre variedades analíticas
(Universidade Federal de São Carlos, 2006-03-03) Silva, Marcela Duarte da; Tomazella, João Nivaldo; https://lattes.cnpq.br/0051564735964760
The study of analytic germs of functions (Cn, 0) → (C, 0) under R - equivalence relation is a central point in Singularity Theory and the information we have in this direction is very rich. In this dissertation we have a study similar for an equivalence relation which preserve certain analytic variety X, the RX - equivalence.
Análise química de materiais argilosos e refratários modificados durante moagem por espectrometria de emissão óptica com plasma acoplado indutivamente
(Universidade Federal de São Carlos, 2006-03-03) Santos, Mirian Cristina dos; Nóbrega, Joaquim de Araújo; https://lattes.cnpq.br/8833989058164529
The main goal of this thesis was the investigation of alternative procedures for chemical analysis of refractory materials and clays using an inductively coupled plasma optical emission spectrometry (ICP OES) with axial view by direct analysis of slurries and microwave-assisted alkaline digestion. The preliminary experiments of this work focused the introduction of slurries into the ICP OES with axial view and evaluated the effects caused by the particle size distribution on the intensities emission signals. Afterwards, a grinding method in which solid samples were ground together with chemical modifiers was developed. The chemical modifiers studied were LiBO2 and Na2CO3, since they are frequently used as fluxes in fusion procedures, and NH4Cl, ascorbic acid, and graphite. The effects of the chemical modification on the intensities of emission signals and the grinding time required for obtaining greater intensities emission signals were evaluated. The chemical modification procedure was implemented in order to promote the formation of new compounds with thermal properties different of the original materials. The synthesis of less refractory compounds would favor the process of atomization-excitation of the chemically modified materials in the direct analysis of slurries, and it would also facilitate the digestion of these materials. The effects of the chemical modification were also evaluated by using X-ray diffraction and thermogravimetric analysis. The direct analysis of chemically modified materials by ICP OES required the investigation of several calibration methods based on different approaches: use of aqueous reference solutions, calibration with slurries prepared using certified reference materials, and calibration using the generalized standard addition method. The calibration is the most critical aspect in the direct analysis of slurries by ICP OES, because is critically dependent on the particle sizes and of the thermal behavior of the several mineralogical phases of each material. On the other hand, microwave -assisted digestion was investigated in two alkaline media: KOH and NaOH. Applying a paired t-test it was shown that results were in agreement at 95% confidence level with those obtained by microwave-assisted acid digestion. The values of the detection limits and signal-to-background ratio obtained for the two microwave -assisted procedures were compared, and the alkaline digestion has shown adequate performance for the digestion of the chemically modified materials.
Uma modificação da extensão do algoritmo AID para modelos lineares generalizados usando reamostragem Bootstrap
(Universidade Federal de São Carlos, 2006-03-03) Presotti, Cátia Valéria; Barreto, Maria Cecília Mendes; https://lattes.cnpq.br/2218053283392257
One of the most frequently situation found by researchers is to find groups of similar individuals. The cluster analysis is a set of statistical techniques that identify mutually exclusive subgroups or classes over individuals, based on their similarity. When then main is to group means of treatments we can use contrasts, multiple comparitions or clustering techniques as the SCOTT-KNOTT test and AID (Automatic Interaction Detector) technique. In this work we focus on the comparition of the simulated power function of the asymptotic test and also of the bootstrap test for the extension of the AID algorithm for generalized linear models. The bootstrap power function over main the asymptotic power when the number of binomial sample is equal to one, and the number of treatments is equal to 8 and 12, in a completed randomized experiment with a single factor for binomial variables.
Uso de métodos bayesianos em testes de vida acelerados no controle da qualidade de produtos industriais
(Universidade Federal de São Carlos, 2006-03-03) Vieira, Denilton da Silva; Achcar, Jorge Alberto; https://lattes.cnpq.br/3125027713681936
In this work, we introduce a Bayesian approach for quality control of industrial products, assuming units in test under stress levels higher than the usual level. We assume di¤erent distributions for the lifetimes of the units under a type II censoring mechanism and a general stress-response model that includes the usual accelerated life test models. Using a predictive density of a future observation, we present some criteria to be used by engineers in the quality control of a batch of industrial products. These criteria permit a choise for the best time in test or for the best stress level in the quality control test. The quality control procedure is based on the observed proportion of failures tested during a specified time and a specified stress level. We use the software WinBugs (Spiegelhalter et al, 1999) to obtain the posterior summaries of interest. keywords: Accelerated lifetime test, Bayesian Inference, Markov Chain Monte Carlo, Quality Control.