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Conservação, germinação e efeitos alelopáticos de Lafoensia glyptocarpa Koehne
(Universidade Federal de São Carlos, 2010-05-04)
Moraes, Luiza Paiva Silva de
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Perez, Sonia Cristina Juliano Gualtieri de Andrade
;
https://lattes.cnpq.br/9973185407856723
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https://lattes.cnpq.br/1995434984031143
The methodology of the accelerated aging test controlled deterioration to achieve the physiological quality of Lafoensia glyptocarpa Koehne seeds, separated into light and dark seeds, and to correlate if these seeds have their color due to different stages of maturation or whether the color is original phenotypic. The initial quality of the seeds was obtained through the tests of moisture content, conductivity and seedling emergence in greenhouse. The accelerated aging test was conducted at 40ºC during 24, 48, and 72 hours, using the traditional, NaCl saturated solution and controlled deterioration. The research was conducted in a completely randomized design. The saturated salt accelerated aging test and controlled deterioration was efficient for vigor evaluation of Lafoensia glyptocarpa Koehne seeds, and the period of 48hours at 40ºC was considered as the most adequate procedure to evaluate seed vigor levels, leading to the belief that colored seeds come from different stages of maturation.
Análise sistêmica das massas de tamponamento para altos-fornos
(Universidade Federal de São Carlos, 2010-05-05)
Ribeiro, Aloísio Simões
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Pandolfelli, Victor Carlos
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https://lattes.cnpq.br/7369376873984839
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https://lattes.cnpq.br/3511102682668805
The increase in the world steel production mainly observed in the last decade demanded a significant growth in the hot metal production through the blast furnace process. A key point in blast furnaces operation is related to the taphole mix used to plug the hole that is where the tapping is carried out. The taphole mix is a key aspect for the production flow of integrated mills because, in the blast furnaces, it is responsible to maintain a stable tapping, ensuring the supply of hot metal to the steelmaking, maintaining all stages of the crude steel plants in synchrony. The taphole mixes for blast furnace are very special products in the broad universe of refractory materials due to its complex chemistry composition, being applied in extreme conditions of temperature and demand. In this context, the literature and the technical aspects related to taphole mixes require a more comprehensive technical contribution, considering the influence of some additives on their properties. The aim of this work is to evaluate the influence of different raw materials and additives on the properties of taphole mixes related to their densification, adhesion and usinability features. The results of the tests were assessed according to the AHP (Analytical Hierarchy Process) method, which allows for the selection of the best formulation considering all the parameters involved.
Potencial alelopático de extratos aquosos de duas espécies de Gleicheniaceae sobre espécies infestantes de culturas e da bioindicadora Lactuca sativa L
(Universidade Federal de São Carlos, 2010-05-05)
Voltarelli, Valquíria Marin
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Lima, Maria Inês Salgueiro
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https://lattes.cnpq.br/2171993314203162
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https://lattes.cnpq.br/2475606695695985
This work aims to determine through bioassays the allelopathic potential of aqueous extracts Gleichenella pectinata and Dicranopteris flexuosa adult and mature fronds in two physiological stages (fertile and sterile) over the percentage and average time of germination, besides initial growth of three species of crop weeds (Echinochloa crus-galli, Ipomoea grandifolia, Euphorbia heterophylla). Four aqueous treatments were made (0, 2,5 , 5 and 10%), with five replications. Each plot consisted of 30 seeds for germination tests and 10 seedlings for initial growth of root and hypocotyl / coleoptile. Root growth was the most sensitive parameter to G. pectinata and D. flexuosa allelochemicals, for the three target species. All extracts damaged root growth of target species, excepting the lower concentration of sterile fronds extracts over E. heterophylla. Sterile frond extracts caused a delay on E. crusgalli and E. heterophylla germination under concentrations 5 and 10%. The higher concentration of fertile frond extract decreased germination percentage of the three target species. All D. flexuosa extracts decreased root length of all target species. I. grandifolia was the most sensitive species due to D. flexuosa extracts, having showed decrease in all morphologic parameters. Both other target species also had their shoot part length growth suppressed under 5% and 10% concentrations. A soil experiment was also performed in order to verify the role of different treatments of D. flexuosa fronds on Lactuca sativa germination in presence or absence of microorganisms. Each treatment was tested with 4 lettuce seeds per vase, by 10 days with 6 replications. Treatments were tested in 6 periods of ten days each, related to the 1st, 2nd, 4th, 8th, 16th and 32nd days after treatments application. Light, moisture and temperature conditions were controlled. In general, non-sterilized substrates presented higher allelopathic effects over analyzed parameters. Among treatments, the pre-occupied soil exerted stronger effects, with inhibition of germination in non-sterilized, during the whole period of experiment. That must be an indicative of accumulated allelopathic substances under environmental conditions, and their prolonged effects.
Análise sistêmica dos fornos de cozimento de anodo para a indústria de alumínio
(Universidade Federal de São Carlos, 2010-05-05)
Tiba, Paulo Roberto Teruo
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Pandolfelli, Victor Carlos
;
https://lattes.cnpq.br/7369376873984839
;
https://lattes.cnpq.br/2522985758255838
The recent global economic crisis allied with the trend for sustainable companies and countries have meaningfully changed the aluminum area. Previously, the productivity was the main focus of the metal producer and no concern regarding the impact of this activity in the environment was considered. Nowadays, the search for low metal production cost, the reduction of residues and energy-saving aspects are the driving-force for the companies’ competitiveness increase. In this sense, the materials research can be an additional tool as providing new technologies and improvements to the metal production process. Therefore, a systemic analysis was performed for anode baking furnaces considering the dense refractory materials, the post mortem analysis, the insulating materials and the heat transfer. The results attained for the mechanical and thermomechanical characterization of the dense refractories led to insights for the furnace maintenance cost reduction, such as the choice of high performance compositions and the frequent chemical control of both, fluid coke and green anode. Additionally, this work allowed better commercial inputs for the aluminum producer due to the technical development of new refractory suppliers. Regarding the insulating materials and the heat flow, alternatives for energy-saving were visualized, highlighting the use of an insulating blanket on the upper part of the furnace. As a conclusion of this work, the correlation between refractory, energy, sustainability and productivity was better understood for anode baking furnaces, besides the development of novel actions for the aluminum company in order to improve its competitiveness.
Concepções de educação ambiental e perspectivas pedagógicas de professoras do ensino fundamental e as potencialidades do Pólo Ecológico de São Carlos (SP)
(Universidade Federal de São Carlos, 2010-05-06)
Iared, Valéria Ghisloti
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Oliveira, Haydée Torres de
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https://lattes.cnpq.br/5458113597909705
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https://lattes.cnpq.br/1273203310250467
Since 1970´s, in Brazil, a series of educational proposals have incorporated activities related to environmental issues among then outdoor activities in natural spaces. However, we consider that most of those activities don´t take full advantage of its educational potential, both in order to explore all the contributions that the ecology field can offer, or to work with social mobilization and the formation of values. Moreover, it is relevant to identify how primary school teachers deal with three spheres of the educational practice (knowledge, ethical and aesthetics values, and participation) that we consider inseparable in an effective environmental education work. To investigate if the units of the São Carlos Ecological Pole (Pólo Ecológico de São Carlos) are educating spaces that contribute to the understanding of the complexity of environmental issues, and stimulate a sense of belonging and social responsibility, we interviewed primary school teachers who had accompanied visits to these places, people who are involved or have been involved with environmental education (EE) in these spaces, and followed guided tours in all units of the Ecological Pole. To present the results, we chose to discuss them in two stages: Moment I: analysis of all collected material trying to define what each unit of the Ecological Pole can offer, based on 21 listed parameters that are consistent with a critical perspective of EE and Moment II: an analysis of teachers´ interviews aiming to relate the different trends in environmental education conception and educational perspective. Regarding the Moment I, we have identified that the activities of EE in the Pole units can address issues that contemplate the three dimensions of educational practice. This brings up the idea that the issues involve more than one subject, which is consistent with our view that it is up to the EE to unveil the complexity of environmental issues. When we look at each site independent of each other, we realize that many parameters are not dealt with, but when considering the sum of these parameters, we observe that all are identified. This shows the importance of an EE that is permanent and continuous inter and transdisciplinary, requiring partnerships between multiple instances to be viable. The connectivity between the Pole units in a coordinated action would increase each unit´s actions. Therefore, we reinforce the idea that the integration of these units would yield a more thorough EE work. There are certain parameters that are still not addressed frequently. Thus, we envisage a permanent and articulated EE so that other issues, on occasions other than during these visits, can be discussed and reflected upon. For the Moment II analisys, we considered three perspectives of educational trends and three EE conceptual tendencies. We noticed the coexistence of several trends in the same speech, which indicates that the school is reflective and reflects the transition of paradigms through which society in general is going through, and hence the knowledge production in the EE field. From this evidence, we believe that the institutionalization of EE among different groups and social sectors can make the challenge of greening a less arduous task for the school. We identified that the EE actions, both at school and in field activities, do not incorporate all the points that deserve to be addressed in regard to the complexity of environmental issues. The results of this research show how an cross, permanent and continuous EE is a decisive factor for the realization of its principles and objectives.
Avaliação de deformidades morfológicas em larvas de Chironomus (Diptera, Chironomidae) na bacia do rio Piracicaba e sua aplicação no biomonitoramento
(Universidade Federal de São Carlos, 2010-05-06)
Bonani, Fabiana
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Gessner, Alaíde Aparecida Fonseca
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https://lattes.cnpq.br/8465752836529703
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https://lattes.cnpq.br/2018531670661947
The Piracicaba river basin is considered one of the most polluted in the state of São Paulo. It is located in a region with high population density in addition to great development of agribusiness and chemical, textiles, metals, electronics, automotive and paper industries. The objective of this study was to analyze the incidence of morphological deformities in the mentum of Chironomus larvae of this basin, especially in the basin of Quilombo stream. Physical and chemical analysis were performed in water and sediment, ecotoxicological and mutagenicity tests and analysis of the benthic community at ten sampling sites in August 2007. The influence of domestic sewage in the sampling sites was evidenced by analysis of surface and bottom water, which in general, gave results outside the limits established by CONAMA Resolution 357/2005. In the sediment it was detected the presence of metals and PAHs at higher concentrations than the limits established by CONAMA Resolution 344/04, besides the acute toxicity to Chironomus sancticaroli and Hyalella azteca larvae. The best environmental condition for the benthic community was observed in Jacuba stream and Piracicaba river, upstream of the Quilombo stream, which corresponds to the most preserved area. The major incidence of morphological deformities in the mentum of Chironomus evaluated in sediment samples were observed at two points located in the Piracicaba river (Points 2 and 3), downstream of the Quilombo stream, with 25.3% and 36.3% of deformities, respectively, and the lack of teeth was the most common type of deformity. In terms of environmental quality, Chironomus larvae collected in vegetation offered an additional parameter for some sites, because the sediment offered no significant number of larvae. In most of sampling sites it was not observed a direct correlation between the frequency of gross deformities and the level of contaminants, with the exception of zinc. It is suggested the value of 2% for the limit of natural incidence of deformities in non-impacted environments. Further investigations should be conducted in reference sites in the country, with the objective to include this variable in monitoring programs of environmental quality.
Algodão branco e colorido cultivado no sistema orgânico com plantio direto em diferentes coberturas de solo
(Universidade Federal de São Carlos, 2010-05-06)
Arantes, Eurípedes Maximiano
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Margarido, Luiz Antonio Correia
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https://lattes.cnpq.br/5685663057214334
Considered as alternative management more appropriate for tropical conditions, the no-tillage system can follow the principles of organic agriculture and contribute to the evolution and sustainability of organic cotton production systems. In order to generate usage information about soil covering plants for white and colored cotton fibers production in the organic system with no-tillage, an experiment was conducted in the farming years 2006/07 and 2007/08 in Cáceres-MT, with randomized block design, treatments disposed in scheme of split plots and four replicates. In the plots, were evaluated soil coverage consisting of crop residues of Estilozobium aterrimum, Cajanus cajan, Canavalia ensiformes, Crotalaria juncea, Pennisetum glaucum cv ADR 300, Sorghum bicolor cv BRS 307, mixture of species used, spontaneous vegetation and exposed soil. In the sub plots were evaluated upland cotton cultivars BRS ITAUBA (white) and CNPA AMT 19 (brown) in no-tillage on the crop residues of the soil covering plants cultivated in pre-planting. The plant coverage produces phytomass in sufficient quantities for adequate soil coverage. The Estilozobium aterrimum, in a general manner, shows greater extraction capacity and accumulation of nutrients, high lighting the potential cycling of nitrogen and phosphorus, while Pennisetum glaucum and Crotalaria show, respectively, greater potential cycling of potassium and magnesium. The crop residues of Canavalia ensiformes, spontaneous vegetation and Crotalaria provide low persistence coverage, while Pennisetum glaucum residues and Cajanus cajan provide more persistent coverage. During the process of residues decomposition, the nutrients following this descending order of release: K > P > N = S > Mg > Ca, being the potassium the nutrient with faster release and subject to losses. The Estilozobium aterrimum shows greater weed suppression capacity, showing potential for use in production system without application of herbicides, in contrast with the low suppression capacity of Pennisetum glaucum plants and spontaneous vegetation. The contribution of plant coverage residues promote on the surface layer of soil increases in values of attributes pH, MOS, P, K, Ca, Mg, V e CTC. The coverage does not influence the characteristics of fibers, but exerts significant effects on agronomic characteristics and productivity of cotton. The highest yield occurs in straws of Crotalaria juncea, Canavalia ensiformes, Estilozobium aterrimum and mixture of species. The cotton cultivars of brown fiber (CNPA AMT 19) shows productivity and quality of fiber lower than the cultivars of white fiber (BRS ITAÚBA), however has fibers with characteristics that meet the standards required by the textile industry.
Lobby: uma revisão crítica da literatura brasileira (1994-2007)
(Universidade Federal de São Carlos, 2010-05-06)
Marinello, Rita de Cássia Laude
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Noronha, Eduardo Garuti
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https://lattes.cnpq.br/6908348693613769
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https://lattes.cnpq.br/8246054631389764
This essay is a critic review about the term lobby in Brazil. The redemocratization and the Federal Constitution, wich accured in the early decades of 1980, the studies about politics were worried about the mechanism, working and the efficacy from the politics institutions. From this way, the studies about interested groups, pressure groups and the lobby are dated from 1994 to 2007. In this work, these are two most important discussions: (a) the lack of scientific searching from Brazilian winters, means, the necessity to discus a better conception between groups in a common interested, pressure groups and the lobby to procure an empiric searching without failures; (b) the matter of don´t make use from the north-american lobby model in Brazil for the reason of each country has difference means for social matters, economy, culture, history and politics. Even with the studies about lobby in Brazil, also, there was the bibliographic analyses exposed by the collective action of Mancur Olson. The importance of democracy and the pluralism of developed organized and the grammar of Brazilian politics.
Acessibilidade aos pontos de ônibus : estudo de caso em São Carlos
(Universidade Federal de São Carlos, 2010-05-06)
Antunes, Juliana Carmo
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Sanches, Suely da Penha
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https://lattes.cnpq.br/3857424839674606
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https://lattes.cnpq.br/7843517764800624
This work is the result of a research which subject is the accessibility to public transit at medium cities, being the case study applied at São Carlos-SP and its structures of access to the urban public transportation. It is an applied research, which aims to generate knowledge related to transportation and urban mobility studies. Taking into consideration aspects of exploratory and quantitative natures, it aims to provide familiarity to walking and pedestrian issues, and its relationship to public transit traveling. The finding results bring the main transit user s characteristics, and indicate the security issue as the one of most perception and relevance to people s choice, indicating that the creation of accessible routes is not related only to aspects of walking path, but also to urban design and social dynamics.
Determinação experimental da força de adesão entre partículas e meios filtrantes constituídos de celulose
(Universidade Federal de São Carlos, 2010-05-07)
Faustino, Patrícia Brígida
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Aguiar, Mônica Lopes
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https://lattes.cnpq.br/0431688649128529
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https://lattes.cnpq.br/6807169442685729
The influence of particle size, compression velocity, and of the material constituting the substrate on adhesion force between particle and substrate was investigated in this study. The centrifuge technique was applied for compression velocities (press-on) of 500, 1000, and 1500 rpm and detachment velocity (spin-off) of 500 to 14000 rpm. A microcentrifuge (MA 860, Marconi Equipamentos) of maximum rotational velocity of 1400 rpm was used during trials. The velocity of the centrifuge promoted the compression (press-on) and the detachment (spin-off) of particles on the surface of the substrate. Two tubes made of aluminum were placed in the rotor of the microcentrifuge to hold the adapters also made of aluminum. The adapters worked as supports for the substrate containing the particles of the particulate matter. After compression and after each decompression, pictures of the surface of the substrate containing the particles were taken and each image was analyzed in an image analysis program (Image-Pro Plus 6.0) in order to count adhered and detached particles. When it comes to evaluating the influence of particle-substrate adhesion force by using the centrifuge technique, phosphate concentrate (ρp=3.18 g.cm-3) was used as particulate matter. The diameter ranges studied for the particulate matter were of 9 22; 22,1 40; 40,1 54 and 54,1 77 μm. A cellulose filter paper and a cellulose ester membrane were used as substrate. The phosphate concentrate particles were pressed against the surface of the paper filter and of the membrane individually with help of the centrifuge at specific compression centrifuge velocities and, afterwards, the adhesion profile was determined. It was observed that the adhesion force increased with an increase in rotational velocity of the centrifuge applied in the compression and with an increase in particle size of the particulate matter. It was also verified that the adhesion force between the phosphate concentrate particles and the paper filter was higher than that of the membrane, which led to the conclusion that the structural arrangement of filter media had an influence on the detachment process of particles, consequently influencing on adhesion force value.
Professores negros, experiências de discriminação, de racismo e pedagogias anti-racistas
(Universidade Federal de São Carlos, 2010-05-07)
Machado, Lúcia Helena de Assis
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Silva, Petronilha Beatriz Gonçalves e
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https://lattes.cnpq.br/0802503359567533
The presente work has a objective the a analysis by the memory and telling of personal and professional experiences of discriminations and racism lived by eight black teachers, for through them to understand the position accepted by the same teachers up against the racial question, or in the school circle or out of it. It also analizes how the discriminatitory experiences contribute in bigger or smaller grade for these teachers build anti-racism strategies or educations with the object to finish with the racial discrimination and prejudice. The position of the teachers varied between a combative position of fight, silence, refuse, face in the personal circle till the build of strategies, even if in the individual fighter field of discrimination.
Potencial alelopático de macrófitas aquáticas e a influência dos fatores ambientais na sua distribuição em um estuário cego
(Universidade Federal de São Carlos, 2010-05-07)
Takao, Leandro Kenji
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Lima, Maria Inês Salgueiro
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https://lattes.cnpq.br/2171993314203162
;
https://lattes.cnpq.br/9030693363195106
Tropical blind estuaries have a flooding regime that exposes the flora to extreme changes in environmental conditions. Salinity and flooding seem to be the major factors influencing vegetal species distribution in these environments. Aquatic macrophytes are one of the most productive communities and through their metabolism are able to influence aquatic ecosystem. Allelopathic interactions are among the factors that affect phytosociology and are increased under biotic and abiotic stress conditions. The allelopathic potential has been explored for its application as natural herbicide in weed species control. The aim of our study was to evaluate salinity and flooding influence on species distribution, diversity and richness. We also studied and compared allelopathic properties of aquatic macrophyte species and their possible application to inhibit weeds. For this, we studied the macrophytes´ community and its relation with abiotic variables (flooding and salinity) in Massaguaçu River tropical estuary, located in Caraguatuba-SP. We found 54 macrophyte species belonging to 27 families in this environment. The distribution of these species seems to be related to flooding regime and salinity. Species diversity and richness vary with flooding time but not with salinity. Vegetation presents a sequence of heterogeneous communities through saline gradient and flooding categories. Thereby, Massaguaçu River estuary is defined as a double ecocline: lengthwise (between freshwater and seawater) and lateral (between terrestrial and aquatic habitats). We noticed several species with allelopathic potential over lettuce, a bioindicator species, in laboratory experiments with different inhibition potentials. Then, we found significative inhibitory effects of Ipomoea cairica (L.) Sweet extracts on the germination and early development of weed species: B. pilosa, E. crusgalli, E. heterophylla e I. grandifolia. Our results help to understand tropical blind estuarine environment and its floristic compositon, characterizing their vegetable populations, distribution and potential to be explored as an alternative to synthetic herbicides.
O papel dos receptores 5-HT3 da amídala na modulação da ansiedade em camundongos expostos ao labirinto em cruz elevado
(Universidade Federal de São Carlos, 2010-05-07)
Laine, Letícia
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Souza, Azair Liane Matos do Canto de
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https://lattes.cnpq.br/2352004564367849
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https://lattes.cnpq.br/2611147467634592
Aversive situations may activate the serotonergic system, which, in turn, emit projections to structures involved in the defense mechanisms such as: septum, hypothalamus, hippocampus, periaqueductal gray and amygdala, producing behavioral alterations that can be characterized as anxiety. Various studies have related the 5-HT3 receptor functions to anxiety-like behaviors. However, serotonin (5-HT) presents a dual role in this modulation. The elevated plus-maze (EPM), based on the rodents natural aversion to open spaces, is one of the most widely employed models used to study anxiety in rodents. Thus, this study investigates the effects of an agonist and an antagonist of 5-HT3 receptors, mCPBG and ondansetron, respectively, on mice exposed to the EPM. Conventional anxiety measures (percentage of open arms entries and percentage of open arms time), locomotor activity (frequency of closed arms entries) and ethological measures related to the risk assessment were registered. The results demonstrated that, in experiments 1 and 2, the intra-amygdala injections of ondansetron (0.3, 1.0 and 3.0 nmol/0.1Ql) and mCPBG (10 and 20 nmol/0.1Ql), produced a decrease and increase, respectively, of the indices of anxiety in mice evaluated on the EPM. In experiment 3, the local ondansetron injection (0.03 nmol/0.1Ql), was able of reverting the anxiogenic effect caused by the mCPBG (10 nmol/0.1Ql). Taken together, these results suggest that the modulation of the 5-HT3 amygdala receptors for the 5-HT receptors in mice, may display an anxiogenic role.
Estudo das propriedades estruturais e de transporte eletrônico em nanoestruturas de óxidos semicondutores e metálicos
(Universidade Federal de São Carlos, 2010-05-07)
Berengue, Olivia Maria
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Chiquito, Adenilson José
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https://lattes.cnpq.br/7087360072774314
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https://lattes.cnpq.br/1312983845888585
The structural and transport features of oxide nanostructures synthesized by a vapour phase aproach: the VLS and VS methods were investigated in this work. ITO and In2O3 nanowires were characterized by using XRD, HRTEM and FEG-SEM techniques. Both nanostructures were found to be body-centered cubic (bixbyite, point group Ia3) single crystals with a well defined growth direction. Raman spectroscopy was used in order to study the nanowires composition, crystalline character and the role of tin atoms in the In2O3 lattice (ITO) was studied as well. The influence of the structural disorder induced by doping was pointed as the main cause of the break of the selection rules in ITO and it was promptly recognized in the Raman spectrum. The metallic character observed in In2O3 micrometric wires was assigned to the electron-phonon scattering in agreement with the Bloch-Grüneisen theory. ITO samples with different sizes were analysed in the framework of the Bloch-Grüneisen theory and at high temperatures (T > 77 K) they were found to present a typical metallic character. It was observed at low temperatures (T < 77 K) and in small samples a negative temperature coefficient of resistance which is an evidence that quantum interference processes are present. A weak localized character was found in these samples as detected in magnetoresistance measurements. The electron s phase break was associated to the electronelectron scattering (T < 77 K) and the electron-phonon scattering (T > 77 K). The transport measurements in one-nanowire based FET provided data on the electron s mobility and density. Tin oxide nanobelts were also studied and their structural and electrical characterizations were obtained. In this case the association of several structural measurements provided that the samples are rutile-like single crystals (point group P42/mnm) grown by the VS mechanism. The transport measurements provided data on the nanobelts gap energy (3.8 eV) and on the transport mechanisms acting in different temperature ranges. An activated-like process and the variable range hopping were found to be present in different temperature range and additionally the localization length was determined. The influence of additional levels inside the gap caused by oxygen vacancies was studied by performing light and atmosphere-dependent experiments and as a result a photo-activated character was detected. Thermally stimulated current measurements provided evidence that only one level associated to the oxygen vacancies at 1.8 eV seems to contribute to the transport in SnO2 nanobelts. Triclinic single crystalline nanobelts were identified as the Sn3O4 phase and were analyzed by transport measurements. The samples were wide band gap semiconductors and the role of oxygen vacancies was identified by using PL and PC measurements. The semiconductor behavior was confirmed by the electron transport data, which pointed to the variable range hopping process as the main conduction mechanism (55 K < T < 398 K) and data on localization length and on the hopping distance were obtained. The presence of additional levels due to oxygen vacancies and tin interstitials was recognized in the samples by performing photo-activated and thermally stimulated current measurements.
Polarização de spin em heteroestruturas semicondutoras contendo pontos quânticos de InAs
(Universidade Federal de São Carlos, 2010-05-07)
Santos, Ednilson Carlos dos
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Gobato, Yara Galvão
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https://lattes.cnpq.br/7558531056409406
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https://lattes.cnpq.br/5543466901202809
In this work, we have studied spin polarization of carriers in a resonant tunneling diode GaAs/AlGaAs with InAs quantum dots in the center of the quantum well. We have observed that the photoluminescence of quantum dots depends on applied voltage and light intensity. Our results were explained by the capture of minority carriers (holes) to quantum dot energy levels in the resonant conditions. We have also studied the polarized resolved photoluminescence under magnetic field applied parallel to the tunnel current. We have observed that the degree of circular polarization is voltage-dependent under low voltage and laser intensity condition. We have also observed that the degree of polarization of quantum dots tends to zero for high applied voltages. Our results show that the circular polarization depends on the injection and capture of holes by quantum dots. Finally, we observed that the circular polarization from quantum dots can be voltage and light-controlled and could be interesting for the developing of new spintronics devices.
Estudo experimental e numérico da fluidodinâmica e das transferências de calor e massa em um leito de jorro contínuo: uso da técnica CFD
(Universidade Federal de São Carlos, 2010-05-10)
Rosa, Cezar Augusto da
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Freire, José Teixeira
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https://lattes.cnpq.br/2270677706718167
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https://lattes.cnpq.br/6540467268812748
In this work, the transport phenomena, which occur during the drying operation in a continuous spouted bed, are evaluated through experimental data and CFD simulations. Thus, this thesis was divided into three main parts: fluid dynamics, heat transfer and mass transfer. The fluid dynamics of a spouted bed, with continuous solids feeding, was studied through experimental data of static pressure, fountain height and air mass flow rate. A two-fluid two-dimensional model using the Euler-Euler approach was applied to simulate the fluid dynamics of the system. Gidaspow (1992) drag model was used to describe fluid-particle interface forces and the granular kinetic theory (Lun et al., 1984) to predict the solid phase stress. The commercial fluid dynamics code, FLUENT 6.3, was chosen to solve the model equations. The data obtained via CFD compared well with experimental results. In the heat transfer study, the conservation of energy equation was used, in conjunction with the fluid dynamics model, to simulate the heat transfer between the gas and particles in a continuous draft tube spouted bed. Two different Nusselt number correlations (Gunn, 1978; Kmiec, 1980) were used to calculate the heat transfer coefficient between the phases. The simulated results were compared with the experimental data obtained for the fluid temperature in the draft tube and annulus sections of the bed as well as for the solids outlet temperature. The drying simulations were done by coupling the transport phenomena, fluid dynamics, heat and mass transfer. An equation, based on thin layer drying data, was developed for the drying constant, which is a function of the fluid temperature and gas-solids relative velocity. The drying model presented physically consistent results and it seems to be promising for the drying analysis.
O processo transcriativo de São Bernardo de Leon Hirszman
(Universidade Federal de São Carlos, 2010-05-10)
Bozicanin, José Eduardo
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Monzani, Josette Maria Alves de Souza
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https://lattes.cnpq.br/0505156751073470
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https://lattes.cnpq.br/0331116908238067
The purpose of our research was to recoup some of the ideas about the intersemiotic translation of Graciliano Ramos' novel Sao Bernardo (1934) to the cinema. In this masters dissertation we realised the creative genesis of Leon Hirszman's filmmaking processes by following the path traced by the film-maker since the reading of the homonymous novel to the to the writing of an unknown script and posteriorly in his film editing and sonorization approaches.
Viabilidade prática de Bacillus subtilis para controle biológico de Colletotrichum acutatum, agente causal da queda prematura dos frutos cítricos
(Universidade Federal de São Carlos, 2010-05-10)
Corrêa, Francisco Eduardo
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Campos, Maria Bernadete Silva de
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https://lattes.cnpq.br/5024245659105477
;
https://lattes.cnpq.br/1808199150615064
The objective of the present research was to study the practical viability of Bacillus subtilis (ACB-69) to control Colletotrichum acutatum, the casual agent of postbloom fruit drop (PFD) under field conditions. First, the bacteria was tested in two different concentrations, one at 5% and the other at 10 %, in the experiment conducted on Pera Sweet orange plants grafted on cravo lemon trees (11 years of planting), in a private property located in Botucatu, São Paulo State, Brazil during the 2007/2008 season. The same treatments were repeated in the following season, however, with or without adding a carbon source (molasses at 5%), on Valencia orange plants grafted on Rangpur lime trees (15 years old). Additional studies were also carried out under the same conditions, aiming to determine the most appropriate growth stages of flowers to apply the biocontrol agent, for the best disease control. For all experiments, the biological products were applied with an air assisted sprayer with the additional intent of evaluating its practicality. It was verified that the weekly application of B. subtilis at 5% reduced the quantity of symptomatic flowers by 47%, while the chemical treatment only showed an18% efficiency when compared to the control. On the other hand, weekly applications of B. subtilis (at 10%) or with one week before the application of the other biological treatments caused a greater average number of effective fruits (ANEF). The addition of a carbon source at the moment of application may favor the antagonism of the bacteria; however, the addition is optional, particularly when its ANEF is evaluated. The best moment to apply the ACB-69 isolate to control PFD was in the open flower stage, when the percentage of symptomatic flowers was evaluated, however, when the bacteria is applied during all flowering stages there is a greater quantity of effective fruits per plant. The use of the air assisted sprayer was considered efficient for the antagonistic application, allowing a better distribution of the inoculum on the plant without damaging the bacterial cells, hence, enabling it to be an indication for future microorganism applications to control diseases.
Análise de duas propostas para a reabilitação da marcha em indivíduos portadores de sequelas neurológicas crônicas
(Universidade Federal de São Carlos, 2010-05-10)
Santos, Fernanda Romaguera Pereira dos
;
Mattioli, Rosana
This work is composed of three distinct studies. In the first one, we compared the muscle coactivation of tibialis anterior (TA) and gastrocunemius medialis (GM) during quiet stance and the also during the stance phase of gait in hemiparetic subjects (hemiparetic group, HG, n=12) and in subjects with no neurologic injuries (control group, CG, n=10). We evaluated the TA and GM electromyographic signal and calculated their overlapping ratio (OR). We concluded that these individuals do not present significant coactivation alterations in the stance phase of gait, but in quiet stance they seem to use the coactivation of the non-paretic limb to maintain postural stability. In the second study we investigated the effects of the association of treadmill training with body weight support (TTBWS) associated with strength training of ankle muscles on the motor control in chronic hemiparetic subjects. Fifteen volunteers were distributed into 2 treatment groups: 1) TTBWS (G1; n=7); and 2) TTBWS associated with resistance training for dorsi and plantar flexors (G2; n=8). We evaluated muscle performance of plantar flexion and dorsiflexion in an isokinetic dynamometer through peak torque (PT), total work (TW) and acceleration time (AT) at the speeds of 60°/s and 120°/s. For gait analysis we assessed the ground reaction forces (GRF). There was an increase in PT and TT of plantar flexion at 60°/s in the paretic side, and an increase in the positive peak of the anterior-posterior GRF component in both sides of G2. We suggested that the proposed intervention leads to improvements in the components related to propulsion of gait. In the third study, we evaluated the effect of the robot assisted gait training (RAGT) in children with spastic diplegia. Twenty children (12 male, 5-13 years old) were evaluated for functional outcomes and spatial-temporal patterns of gait before, after and 3 months after the end of the intervention. Comparisons revealed significant improvements on functional outcomes and in gait mechanics. We concluded that RAGT promotes better gait patterns, and that the learning of this new task is retained even after the end of the intervention.
Estudo da interação de íons cobre e cromo com eletrodos de pasta de carbono modificada e polianilina em meio aquoso por técnica de voltametria de pulso diferencial
(Universidade Federal de São Carlos, 2010-05-11)
Lima, Rodrigo Maracajá Vaz de
;
Mattoso, Luiz Henrique Capparelli
;
https://lattes.cnpq.br/5839043594908917
;
https://lattes.cnpq.br/6763854791712123
The electrochemical sensors to measure metallic ions in water and waste water are among the most important areas of research nowadays. The environmental control and monitoring chalenges that stimulated the aim of this work are tanification for industrial leather finishing and cuprous and cupric organic and inorganic fungicides. The features for characterization of metallic ions in water, specially for Cu2+ e Cr6+ and the properties of Humic Acid extracted from Turfe, or Turf Humic Acid (AHT) and Lignossufonic Acid, or Sulfonated Lignin (LigS), were exposed, as well as the properties and synthesis methods for Polyaniline (PAni). The following electrodes were prepaired and used on this work: The carbon paste modified electrodes, prepared with AHT extracted at Mogi river estuarine region near Luis Antonio city São Paulo State, Brazil. Another carbon paste was prepared for comparison with LigS obtained from pinus pulp processing and treatment by Melbar Company (Parana State, Brazil). The working electrode that used PAni films were prepared by electrochemical synthesis onto graphite rods. The cyclic voltammetry technique was used to synthesize PAni in acid media of 0.5 to 1.0 mol L-1 H2SO4 (PAni-H2SO4) and scanning speed of v=20mVs-1, v=50mVs-1. The same procedure was used to synthesize the PAni films, in the same acid media, and the solution has 0.05 mg L-1 of dispersed LigS (PAni-H2SO4+LigS). These electrodes had their Differential Pulse Voltammetry (DPV) current peak response studied with Factorial Planning. The most important results were compared by linear response, sensibility, limit of detection (LD) and repetability. The best electrodes for Cr6+ ions was PAni-H2SO4+LigS with a sensibility of 10.3A/10-7molL-1, 2.87% of repeatability, 5.6% of reproducibility and LD = 1.96 10-8 mol L-1. For copper ions the Carbon Paste modified with LigS was the best electrode wich has a sensibility of 9.5 A/10-7mol L-1, 1.5% of repeatability, reproducibility of 3.5% and LD = 4.9 10-8 mol L-1. Both electrodes have, each other, a linear calibration curve for Ip response that includes the limits of concentration for brazilian s environmental laws (CONAMA 397/april 2008), by DPV method, obtained on acetate buffer, pH=4,5, pulse height zE=75 mV, Ed = -0.35 V and scanning speed v= 20mVs-1.