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A equação de Yang-Baxter para modelos de vértices com três estados
(Universidade Federal de São Carlos, 2011-03-02) Pimenta, Rodrigo Alves; Martins, Márcio José; https://lattes.cnpq.br/1875815921495261
In this work we study the solutions of the Yang-Baxter equation associated to nineteen vertex models invariant by the parity-time symmetry from the perspective of algebraic geometry. We determine the form of the algebraic curves constraining the respective Boltzmann weights and found that they possess a universal structure. This allows us to classify the integrable manifolds in four different families reproducing three known models besides uncovering a novel nineteen vertex model in a unified way. The introduction of the spectral parameter on the weights is made via the parameterization of the fundamental algebraic curve which is a conic. The diagonalization of the transfer matrix of the new vertex model and its thermodynamic limit properties are discussed. We point out a connection between the form of the main curve and the nature of the excitations of the corresponding spin-1 chains.
Dinâmica populacional de Euterpe edulis Martius em Floresta Ombrófila Densa no sul da Bahia
(Universidade Federal de São Carlos, 2011-03-02) Mafei, Rodolpho Antunes; Matos, Dalva Maria da Silva; https://lattes.cnpq.br/4728734263109138; https://lattes.cnpq.br/0804832742490928
Euterpe edulis is a very important palm tree from the Brazilian Atlantic Forest due to its ecological and economic role. However, due to the indiscriminate overexploitation its populations has been reducing greatly. This study aimed to characterize the conservation status of a E. edulis population in a fragment of Atlantic Forest at Southern Bahia. We monitored this population along 5 running years in a 0.8 hectare. Environmental variables were also collected to test which factors could affect plant development and projection matrices analysis were performed to estimate the population growth rate and sensibility. The results showed that population s density is lower if compared with others studies. We verified a decrease in the seedling s recruitment over years, which were attributed to fragmentation side-effects, such as microclimate changes and / or reproductive isolation or inbreeding depression. We also observed that the low rate of transition from stages 1 to 2, represents a bottleneck for the population growth. These results emphasize the urgency of more long-term studies on the population ecology and genetic of E. edulis and also management strategies to promote the sustainability of such natural populations.
Voto: uma oferta de fé. O poder simbólico dos líderes religiosos e o comportamento eleitoral dos membros da igreja evangélica
(Universidade Federal de São Carlos, 2011-03-02) Souza, Julio Cesar Pereira de; Kerbauy, Maria Teresa Miceli; https://lattes.cnpq.br/4762029784021248; https://lattes.cnpq.br/7201126524337975
The way of making politics in the churches in Brazil has changed considerably due to the growth of evangelical denominations. The neopentecostal churches , emerged in the mid-70s, grew up quickly and now they are communities strongly disputed by the political leadership to represent an important portion of the national constituency. Considering the problem of charisma, the symbolic capital, i.e, the influence of the religious leader, we studied the voting behavior of campaigns for state and federal deputies in the International Church of God`s Grace (Igreja Internacional da Graça de Deus) from 1998 to 2006 addressing the transformation of its members in militants and faithful voters. Therefore, we analyze the guidelines of the speech delivered by the church leadership in the process of electoral persuasion, the media material, the logistics of the campaign and the participation of members in this process.
Efeito ansiolítico do ondansetron, antagonista dos receptores 5-HT3, injetado na amídala de camundongos submetidos à exposição e reexposição no labirinto em cruz elevado
(Universidade Federal de São Carlos, 2011-03-02) Nunciato, Ana Claudia; Souza, Azair Liane Matos do Canto de; https://lattes.cnpq.br/2352004564367849; https://lattes.cnpq.br/4045394375772114
Against of stimuli that are dangerous, animals manifest defense reactions that cause fear and anxiety. These stimuli activate the serotonergic system, which sends projections to structures involved in defense mechanisms such as the septum, hypothalamus, hippocampus, amygdala and periaqueductal gray modulates the behavioral changes that can be characterized as anxiety. Studies have shown that 5-HT3 receptors are part of this modulation. The elevated plus maze (EPM) is a widely used animal model to evaluate the anxiolytic activity of drugs. Currently, it is known that the retest in rodents (rats and mice) increases the avoidance of it, this phenomenon, which refers to "a display of tolerance" (OTT, One Trial Tolerance). The amygdala is a prosencephalic structures that have significant amount of serotonin (5-HT) in this way, recent results from our laboratory have shown that microinjections of ondansetron antagonist 5-HT3 receptors in the amygdala of mice produced anxiolytic-like effect evaluated in LCE. The aim of this study was to evaluate the involvement of receptors 5-HT3 receptors in the amygdala of mice prior experience the elevated plus-maze (EPM). Conventional measures of anxiety (% of entry and time spent in open arms), locomotor activity (frequency in closed arms) and ethological measures related to risk assessment were recorded. The present study demonstrated that intra-amygdala of ondansetron, antagonist of 5-HT3 receptors, produced anxiolytic-like effects in naive mice and mice prior experience the LCE. The injection of ondansetron in only one of the exhibits produced anxiolytic-like effect, which leads us to conclude that the drug produced no change in memory. Both the Trial 1 and in Trial 2, none treatments affected locomotor activity. So while the amygdala is involved in the neurobiology of the defense reactions such as anxiety response, as it refers to the phenomenon it seems OTT not to participate.
Homotopias finitamente fixadas e pares de homotopias finitamente coincidentes
(Universidade Federal de São Carlos, 2011-03-02) Cotrim, Fabiana Santos; Vendrúscolo, Daniel; https://lattes.cnpq.br/8602232587914830; https://lattes.cnpq.br/5304106217466160
In the area of the theory of fixed points and coincidences of Nielsen, this study aims to develop techniques to minimize the set of fixed points in homotopies and the set of coincidences in pairs of homotopies. The techniques are based on Hopf construction for selfmaps of polyhedrons and on the results presented by Helga Schirmer in context of _x-finite homotopies. For pairs of homotopies, we created the concept of coincidences finite and we proved that certain pairs of homotopies can have their set of coincidences minimized in order to become coincidences finite.
Monitoramento em tempo real da orientação molecular de poliestireno e em misturas com polimetilmetacrilato durante a extrusão
(Universidade Federal de São Carlos, 2011-03-02) Santos, Adillys Marcelo da Cunha; Canevarolo Júnior, Sebastião Vicente; https://lattes.cnpq.br/4153664441338178; https://lattes.cnpq.br/4714910313876978
In this work it was studied the flow orientation of pure polystyrene and its diluted mixtures with polymethylmethacrylate as second phase during extrusion process by in-line monitoring of the polarized transmitted light intensity. The optical device is attached to the extruder exit by means of a slit-die possessing bores fitted with borosilicate transparent glass windows where light may go through to reach the flow. Upon pressurization, the windows internal structure changes which influences its optical response. The expected sine-square fitting relating transmitted light intensity and applied pressure on the windows is applied to the data. Doing that the software is able to deduct the glass windows strain birefringence from the polymer flow birefringence contribution. Stopping the feed allowed the in-line monitoring at a continuous decrease in shear rate replacing the time-consuming and waste of material of the steady-state. Amidst the samples evaluated, the higher viscosity polystyrene presented a high orientation level inducing an optical path difference above the half first order (OPD > 275nm). On shear rate decreasing the orientation of the flowing polymer reduces, displayed by the optical detector as a change in the transmitted light intensity, following a sinusoidal curve. Addition of a second phase to the PS matrix both lower the transmitted light intensity due to the turbidity created by the scattering particles presented in the medium and shifts the curves maxima to higher pressure values. The latter case is explained by the generation of methyl methacrylate monomer that diffuses into the PS matrix reducing its viscosity and so the chain orientation. Statements above revealed a vector called Azimuthal influence of the Concentration.
Resiliência de sistemas alimentares: do local ao global
(Universidade Federal de São Carlos, 2011-03-02) Ferreira, Marina Vianna; Nordi, Nivaldo; https://lattes.cnpq.br/8168865557947289; https://lattes.cnpq.br/9020309796452848
Síntese assistida por microondas de LiMn2O4, caracterização e testes como catodo para dispositivos de armazenamento de energia
(Universidade Federal de São Carlos, 2011-03-02) Silva, João Pedro da; Biaggio, Sonia Regina; https://lattes.cnpq.br/0418215244233120; https://lattes.cnpq.br/2087603202355409
Lithium manganese oxide - LiMn2O4 - was produced by a microwaveassited solid state reaction. Solid mixtures containing LiOH.H2O and -MnO2 (synthesized electrolytically) underwent microwave irradiation for 3, 4 and 5 min. The obtained material was characterized by X-ray diffraction (XRD), scanning electron microscopy and cyclic voltammetry. Conductivity measurements and charge / discharge tests were carried out with the mixture: 85% LiMn2O4 / 10% carbon black / 5% PVDF. XRD analyses showed that LiMn2O4 was obtained in a single phase of cubic structure belonging to the space group Fd3m in only 3 min of microwave irradiation. This short time for the LiMn2O4 synthesis represents an energy saving greater than 90% when compared with the time employed in the traditional method of synthesis. SEM micrographs showed morphological changes and particle size increase when the microwave irradiation time was increased. The mixture (85% LiMn2O4 / 10% carbon black / 5% PVDF) presented electronic conductivity similar to that of a semiconductor (σ ~ 10-1 S m-1), which is adequate for using as cathode in lithium ion battery. Charge and discharge tests showed good electrochemical stability for all the oxides synthesized at different times, evidenced by a small decrease (12 to 17%) of their specific capacities during 30 cycles of charge and discharge. The oxide produced at 3 min of microwave irradiation presented the highest charge supply (77 93 mA h g-1) at an elevated discharge rate (C/1), besides a highly uniform morphology and the lowest particle size (~1 μm).
Megafauna do quaternário tardio dos depósitos cársticos do Alto Vale do Ribeira, sudeste do Estado de São Paulo, Brasil
(Universidade Federal de São Carlos, 2011-03-02) Ghilardi, Aline Marcele; Bichuette, Maria Elina; https://lattes.cnpq.br/8453043393798516; https://lattes.cnpq.br/5761534317977568
The carbonate caves of the Upper Ribeira Valley, southeastern São Paulo State, Brazil, preserve abundant fossil record of Pleistocene-Holocene South American megafauna. This work presents a historical review of its paleontological studies, as well as an update taxonomic survey of the megafauna material gathered since the beginning of the explorations in the area. Herein are also discussed paleobiogeographic and paleoecological questions and presented new Electron Spin Resonance dating results of the Ribeira s material. The fossil megafauna of the Upper Ribeira karstic region include: Eremotherium laurillardi, Nothrotherium maquinense, Lestodon armatus, Catonyx cuvieri, Ocnopus gracilis‟, Ahytherium aff. aureum, Glyptodon clavipes, G. reticulatus, Hoplophorus cf., Toxodon spp., Stegomastodon waringi, Tapirus terrestris,. Equidae indet., Smilodon populator and Panthera onca, of which only P. onca and T. terrestris still remain in the region. The register of Equidae here presented is the first for this area and also the first formal entry for the São Paulo state. The fossil assemblage recorded shows greater biogeographical affinity to the mega-mammal community of the intertropical region, though a typical taxon from pampean localities was also found. This denotes that the area should be a transition zone. The ecology of the species found suggests bygone occurrence of fairly different environmental settings than the existing one in the area. There were more temperate climates associated with open vegetation physiognomies, what agrees with the already known paleopalinological data. The fossil material does not show any kind of cronocorrelation given the type of genesis of the cave accumulations; and paleoecological investigations indicate that these fossils does not represent a real biocoenosis, but depict different faunistic moments related to climate oscillations during the Quaternary. The results obtained with the absolute dating corroborate the hypothesis that the Vale do Ribeira material belong to Late Pleistocene Holocene age; and also give the first biocronological insight for an extinct group in this area. To better understand the information provided by these deposits, further efforts on prospection and dating should be conducted, as well as detailed taphonomic investigations. The studies of the Quaternary fauna in São Paulo State come to fill an important gap in the intricate history of the South American megafauna.
A influência da preferência por brindes no autorrelato de desempenho em tarefas de leitura
(Universidade Federal de São Carlos, 2011-03-02) Rabelo, Laura Zamot; Rose, Julio Cesar Coelho de; https://lattes.cnpq.br/3386857761295187; https://lattes.cnpq.br/8073723161368032
This study aimed at investigating the correspondence in a do-say activity. Two experiments were carried out: the first intended to clarify the effects of choice and preference for items on the self-report of children in a reading task performed on the computer; the second experiment endeavored to search for effects of previous reinforcement history using the same task as the former. Six children aged between 7 and 10 took part in Experiment 1. Doing consisted of reading a word out loud and saying comprised the report of having emitted a correct answer or having made a mistake. The entire task was performed on the computer. The item preference was determined by an interview done with the subjects themselves and it was also assessed by a multiple-stimuli without replacement test. The self-report of mistakes and correct answers for each subject was registered during three baseline sessions and no differential consequences followed any particular self-report. Afterwards, the subjects were exposed to the testing sessions with the objects evaluated as of high, medium and low preference, with and without the possibility of choosing what item they wanted to obtain. The total number of sessions was 18 and each of them was planned with 50% of words the subjects did not know how to read. The children were informed that they could only receive the treat (one of the preference items) if they had at least 15 points as the final score what would sum up to 75% or more of right answers for each session. Therefore, to every report of right answer, a point was added to the total score and it was presented on a screen shown in the intertrial interval. The percentage of noncorrespondent reports increased during the testing sessions, if compared to the baseline. It can be noticed a progressive raise on the non-correspondent reports of correct answers for all the subjects, nevertheless, the data were variable. The Experiment 2 aimed to broaden the results of the first and also to evaluate the role of historical variables represented here as a correspondence training carried out before the testing sessions. Three children between 7 and 10 years old were the subjects. The results obtained in the second experiment did not substantially differ from the first. Similar to Experiment 1, the data obtained from Experiment 2 for all children show an increase on emission of self-reports of correct answers, regardless if they made a mistake or not. There were not observable choice effects in both experiments. Moreover, the pattern of responses of most of subjects differed from what was to be expected if the reports were in function of preference. In conclusion, it is of fundamental importance to investigate the role of the score shown during the task as it may have functioned as an immediate conditioned reinforcer during the sessions increasing the emission of reports of correct answers. Keywords: verbal/nonverbal correspondence, reading, preference for consequences, reinforcement.