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Influência da compatibilização interfacial seletiva nas propriedades mecânicas de compósitos híbridos ternários de PET/fibra de vidro/elastômeros olefínicos reativos
(Universidade Federal de São Carlos, 2009-09-25)
Carvalho, Gustavo Baldi de
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Sousa, José Alexandrino de
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https://lattes.cnpq.br/7737833809468759
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https://lattes.cnpq.br/2108032825479988
Poly(ethylene terephthalate) (PET) is a semi-crystalline thermoplastic widely used for packaging of aereted soft drinks, which makes the recycling of post-consumer PET material necessary to prevent the negative environmental impact of its disposal. The recycling of PET as an engineering thermoplastic can be accomplished by the incorporation of glass fiber (GF) and elastomeric impact modifier to the PET matrix, forming a ternary hybrid composite. To assure an appropriate balance of mechanical properties of stiffness, strength and toughness in this composite, it is important that the GF and rubber particles are dispersed separately in the matrix, avoiding the encapsulation of the fibers by the rubber phase and promoting, simultaneously GF reinforcement and rubber toughening mechanisms. In this work, the influence of selective interfacial compatibilization on the mechanical properties of hybrid composites of recycled PET was studied, as the matrix polymer was modified with reactive olefin elastomers of E-MA-GMA and E-EA-MAH, as well as with short GF treated with either epoxy (FV952) or aminesilanes (FV983). Ternary systems of PET/E-MA-GMA/FV952, PET/E-MA-GMA/FV983 and PET/E-EA-MAH/FV983 were compounded in a twin-screw corotating ZSK-30 extruder and, depending on the relative reactivities of PET s chain-end groups with the functionalities present on the GF surfaces and in the E-MA-GMA and E-EA-MAH terpolymers, the GF is encapsulated or not by the elastomer phase and, consequently, the mechanical properties of the hybrid composites are affected differently. Mechanical tests and torque rheometry data indicated high reactivity between PET and E-MA-GMA terpolymer, and low reactivity with the E-EA-MAH. Analysis of tensile and Izod impact tests results, as well as from fiber-polymer interfaces observations by SEM, indicated good fiber-polymer adhesion in PET/E-MA-GMA/FV952 and PET/E-MA-GMA/FV983 systems, and fiber encapsulation by rubber particles in the case of the PET/E-EA-MAH/FV983 system.
Mobilidade ascendente, identidade e estilos de vida do negro (a) no interior paulista: o caso de São Carlos e Araraquara
(Universidade Federal de São Carlos, 2009-09-25)
Martins, Thais Joi
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Silvério, Valter Roberto
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https://lattes.cnpq.br/9421231847055027
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https://lattes.cnpq.br/1495908295162360
This work has the focus to bring reflection about identity and trajectory of some black professionals and businessman from west of the State of Sao Paulo. We search to know how these black people walk their path and lifestyle and meaning and remaining their identity when reach important posts and positions at the work market, that is, when reach a raising social and economic mobility. In this way, first counting on a bibliographic review about the thematics cited above and subsequently with an analytic descriptive moment that will count on exposition and analysis of the data obtained in interviews made with middle class black people from local authority of Sao Carlos and Araraquara. It has also the intention to do a qualitative analysis so we can get more precisely results for reflection in a conclusive way about the construction of the black people s identity and insertion in the Brazilian work market.
Metaheurística tabu aplicada ao problema de carregamento de contêiner com caixas idênticas
(Universidade Federal de São Carlos, 2009-09-25)
Poli, Guilherme Izidoro
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Pureza, Vitória Maria Miranda
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https://lattes.cnpq.br/2842453464277778
Intermodal transport, that is, the integration between different transport modes was facilitated by the use of containers. The stowage devices in the breakdown of the cargo is an important logistics activity, since the total volume actually used can affect significantly the cost of transporting the products. This approach addresses the Container Loading Problem, which more generally consists in arranging items (for example, products packaged in boxes) of various sizes within larger objects (for example, containers) with the maximum use of the available volume. In particular, it is considered the special case where the boxes to be arranged are rectangular and identical (single sized) and there is only a single container. In order to tackle these problems, the 2006´s Tabu Search heuristic by Pureza and Morabito, originally proposed for the Manufacturer s Pallet Loading Problem, was extended. From an initial solution generated by a block heuristic, moves are applied to selected blocks in order to change their box orientation and/or to expand them in one of the six directions, which result in the reduction, elimination and creation of other blocks. Criteria for stability of the load are also addressed in this work. Computational experiments using a set of instances in the literature demonstrate the performance of the proposed approach.
Proposta participativa de redesenho agroecológico da microbacia do Córrego Três Barras
(Universidade Federal de São Carlos, 2009-09-28)
Coletty, Carlos Eduardo
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Stolf, Rubismar
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https://lattes.cnpq.br/5598396937740054
The exploration of the extensive livestock and of the coffee s monoculture, nowadays abandoned, associated with the abandonment of traditional cultures led to the degradation of the micro watershed of the Córrego Três Barras at the city of Jacutinga, south of Minas Gerais. For not get the culture of their lands sustenance local agricultural families seek for work in neighboring cities. This reality motivated the search for alternatives that can contribute to ambient, economic and social recovery in this region. The general goal of this work was to established, in a participatory manner, the bases in which this community can redraw their model of occupation through an adoption of agroecological concepts and practices. The specific goal was to indentify the potentialities and the critical aspects through the realization of a Rural Participatory Diagnosis DRP. This case study was made in the farm/site Três Barras, property that features the rural familiar agricultural of the others properties of this agroecosystem. The comprehension/understanding of this diagnosis allowed to the local social actors the beginning of a new development´s draw with the agroecological practices adoption.
Educação para a vigilância do desenvolvimento infantil: formação virtual e presencial para educadores de creche
(Universidade Federal de São Carlos, 2009-09-28)
Neófiti, Cíntia Cristina
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Martinez, Claudia Maria Simões
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https://lattes.cnpq.br/4802235453549037
The literature points out to the presence of biological and environmental risks for the child s development during their first years of life which could be influenced by factors present in several environments. In the national scenario, a day care center has been considered as one of the development contexts for being a place where they cohabit and interact, most of their time, with adults and their pairs. It is believed in this environment that there are early possibilities of risks, delays and deficiencies; the child s stimulation in the daily routine could be emphasized. In this sense, the importance of investments on the formation of educators in the perspective of having them as partners in the surveillance on the infant development foundation stands, therefore, in a preventable action in the field of Special Education. It is understood as surveillance all the activities related to the promotion of the normal development and to the detection of problems in the development. The study hereby aimed elaborating, implementing and evaluating a program of long distance capacitance to the day care center educators (Day care center educators development surveillance program Programa de Vigilância no Desenvolvimento para Educadores de Creche PROVIDEC) for the development of surveillance actions, in practice with babies. There were 47 municipal day care center educators of a medium-sized city from Sao Paulo state who composed the experimental group-EG and the control group-CG. The content of PROVIDEC considered the child development, risk factors and protection mechanisms, surveillance actions, the role of the educator at the day care center, stimulation opportunities in the day care center daily routine and health promotion. PROVIDEC counted on six virtual classes and with two present moments. This study was developed in three stages: preparation of fieldwork, invitation to the participants and composition of the groups; program elaboration; and, implementation and evaluation of the program by means of an experimental delimitation, with an experimental group and equivalent control, and, pre and post-test measures. It counted as well on pre and post-test instruments, characterization questionnaire from the participants, evaluation/perception questionnaire about the program, and the PROVIDEC. The use of those instruments demanded qualitative and quantitative seal analysis. From the results obtained, it is possible to note an increase on the repertoire of participants from the EG where it improves its answers at the moment of the post-test in 79 corporative items to the CG with only 8. From the qualitative point of view, the increase on the repertoire of the participants from the EG happen regarding the following themes related to the surveillance of development: the educator s attitudes at the moments where an abnormality or a risk for the child is noted, regarding the mechanisms of protection, to the marks of the Child Development and to the Risk Factors. Such results are discussed under the optics of the prevention actions in the field of Special Education. Future researches are suggested in the sense of the proposition of interface models among educators and basic health attention professionals to the development of surveillance operationalization actions.
Um modelo de visão computacional para identificação do estágio de maturação e injúrias no pós-colheita de bananas (Musa sapientum)
(Universidade Federal de São Carlos, 2009-09-28)
Tezuka, Érika Sayuri
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Cruvinel, Paulo Estevão
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https://lattes.cnpq.br/7924553462118511
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https://lattes.cnpq.br/4759964900793721
This dissertation presents the development of a computer vision system for bananas (Musa sapientum) analysis in post-harvest stage based on digital image processing techniques. The development used considerations about image acquisition, pre-processing, identification based on texture, percentage of brown spots and injuries on the fruits and classification of its maturity levels. The validation has been developed considering geometric patterns generated in laboratory, as well as real fruits. With the texture map it was possible to identify the existence of brown spots or injuries in a specific region of the images. The assessment of the level of maturation was performed considering both human observers and the computer vision system. The average of identification level of maturity was equal to 50% for human observers and 100% for computer vision. The results show identification rates of 80.40% for brown spots on the single image of banana, 97.70% for brown spots on the images of bundle of bananas, 97.80% for injuries for the set of single image of banana, and 75.30% for hand injuries considering the images of bundle of bananas. Besides, the method presents application for quality assessing of fruits in the post-harvest procedures.
Práticas ambientais nas etapas de geração de matériaprima e de produção em empresas paulistas processadoras de madeira
(Universidade Federal de São Carlos, 2009-09-28)
Bernardo, Júlio Samuel Sávio
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Camarotto, João Alberto
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https://lattes.cnpq.br/1427853773681255
Wood processing companies can, potentially, generate environmental impacts such as wood, water, and energy consumption, and soil, air, water, and noise pollution. In order to conserve the environment, it is necessary that companies adopt environmental practices, i.e., practices for reducing or avoiding environmental impacts. The objective of this study was to analyze the environmental practices adopted by São Paulo state wood processing companies in the stages of generating and acquiring raw material and product production. The complementary objectives were: 1) investigate how the environmental practices adopted influence aspects of production and products attributes; 2) identify the tools used to support the environmental management; 3) identify the major motivating factors that led the adoption of the environmental practices. A qualitative study was carried out in 5 São Paulo state companies that produce wooden products for writing, cellulose and paper, or recycled corrugated fiberboard packaging. The research methodology adopted was case studies. Several interviews were conducted and documents were analyzed, among which are the Sustainability Reports, the Plan of Forest Handling, and other information disclosed on the companies websites. It can be said that the environmental practices adopted by the majority of the companies studied refer to the consumption of wood, water, and energy, and to the pollution of the soil, air, and water. These practices are examples of real solutions found by the companies, and can be the frame of reference for other wood processing companies. In order to improve the environmental performance, it is recommended that each company should evaluate the need and possibility of employing practices mentioned in the literature but that have not been adopted by any of them. Another recommendation is that the companies should improve some environmental practices they have already adopted. In most of the companies, the production cost was increased mainly due to the investments in machinery and equipment. In some companies the price of the final product was raised. Nevertheless, the acceptability of the products in the corporative national and/or international market was increased. The majority of the companies use internally developed tools to support the environmental management. It is recommended that the companies make an effort to attract external support for the continuous improving of the existing tools and also for the development of new tools. It could be concluded that the major motivating factors for the adoption of environmental practices are legislation, market regulation, and factors related to business competitiveness such as the improvement of the environmental image and the possibility of costs reduction.
Composição, estrutura e fatores determinantes da ictiofauna de um reservatório neotropical: Cachoeira Dourada, Goiás - Minas Gerais, Brasil
(Universidade Federal de São Carlos, 2009-09-29)
Marçal, Alexandre Sorókin
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Peret, Alberto Carvalho
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https://lattes.cnpq.br/0995579236780271
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https://lattes.cnpq.br/6851252464778461
This study aimed to characterize the composition and structure of the ichthyofauna of UHE Cachoeira Dourada (15 º 27'S and 44 º 41'W), which has about 74km2 (average) of flooded area. Therefore, we selected two points (P1 and P2) for fish sampling, in which were installed batteries of 10 gill nets, each 50m long, 2.0m high, with meshes respectively, 2.0cm to 6.5cm between adjacent knots. These points were sampled from February 2007 to January 2008. In September 2007 we added a point (P3) upstream of the reservoir in an oxbow lake, which was also sampled using gill nets. The nets were left in water for 24 hours and the harvesting was done every 12 hours. In addition, physical and chemical data were collected in both surface and bottom on 05 points distributed along the reservoir, and 01 immediately downstream of the dam, in order to characterize the system. The limnological parameters values were similar for each of the points, and did not show the typical gradient from the river towards dam. There was no vertical stratification of temperature or oxygen. The seasonal variation of limnological parameters (between the rainy and dry months) was greater than the longitudinal variation within each period. These facts suggest that the small size of the reservoir, its shallowness and non-dendritic shape closes its limnological behavior to that of a lotic system. A total of 1988 specimens and 326.16 kilograms of fish were captured. These were divided into four orders, 15 families and 35 species. Six introduced species accounted for 32% of the catch in numbers and 29% of the catch in biomass. The assemblages at points P1 and P2 were adjusted to the logarithmic model of rank-abundance. Simpson's diversity was high (> 70%), except during the dry season in P2. The most abundant species in the three points, in decreasing order of importance, were Pimelodus maculatus, Satanoperca papaterra, Pinirampus pirinampu, Cichla piquiti, C. kelberii, Astyanax altiparanae, Schizodon nasutus and Serrasalmus maculatus. The seasonal variation in abundance correlated with pH and water transparency. Among the reproductive guilds, four long-distance migratory species were the most abundant in terms of numbers and biomass. The group with the largest number of species was the guarders, which was also the second most abundant in numbers and biomass. Carnivores dominated in numbers and biomass, followed by piscivores and benthic-feeders. This fact, combined with the low abundances of illiophagy and herbivores, suggests that the energy used by the fish fauna is of allochthonous origin, similar to lotic environments. Correspondence of species with different points was related to habitat heterogeneity, availability of food resources and biotic interactions such as predation and competition.
Aspectos executivos e a qualidade de estruturas em concreto armado : estudo de caso
(Universidade Federal de São Carlos, 2009-09-29)
Takata, Leandro Teixeira
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Figueiredo Filho, Jasson Rodrigues de
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https://lattes.cnpq.br/0732866094426766
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https://lattes.cnpq.br/7402392342005625
The execution of reinforced concrete structures is a construction stage that has significant importance in the overall context of a work and involves materials, suppliers, work fronts in the workplace and a large number of professionals. In this stage many problems may occur: inadequate use of materials, misinterpretation of the project, incorrect use of equipments, action of weather and other inconveniences. Carelessness at this stage can lead to major schedule delays and extra costs, as this will require new tasks, materials and equipment not predicted (a new set of forms can be used, but the material and labor for the service may not be available). Surveillance and attention are needed for a good final product which, however, is not always achieved. That is where the pathology of structures acts, aiming to correct and prevent failures in all constructive stages. Otherwise, problems may appear in the global chain of the work, leading to the need to restructure the process of execution of the building. Therefore, several authors propose standard, and even alternative, construction methods, companies provide manuals of performance and quality control of materials and the codes propose minimum requirements for safety, durability and quality of buildings. To study and improve the execution phase means, therefore, avoiding delays and additional costs, as well as ensuring that the building will have quality and durability. This paper analyzes the execution phase of a given multiple floor building, pointing out mistakes and their possible influences on the quality of the building during its service life.
Mecanismos enunciativos no ensino de língua : entre o erro e a criatividade
(Universidade Federal de São Carlos, 2009-09-30)
Bertolo, Larissa de Oliveira
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Onofre, Marilia Blundi
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https://lattes.cnpq.br/4908382415301882
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https://lattes.cnpq.br/6358351541849570
This work falls within the scope of the enunciative-linguistic research. We want to build a relationship between linguistic analysis and practice of teaching and learning of mother language, speeded us on the theoretical and methodological perspectives of the Theory of Enunciative Operations developed by Antoine Culioli. The research question refers to the shifts of the enunciative marks of person-space-time in the textual production of the student in process of teaching and learning. Such enunciative shifts, as we have noted, can cause the student s textual compromise. Considering that the context in question is the teaching and learning language, we believe that such occurrences involve the cognitive-linguistic development of the student, a fact which interests us as a background for the linguistic issues focused here. The corpus of analysis is composed of assignments and fables texts. In the latter, the enunciative shifts do not compromise the production of meanings of the text, contrary to what occurs, in general, in school texts. To achieve the specific goals, we seek to understand the movement between the marks of person-space-time in the utterances of school texts and of fables, concentrating our analysis on the lexical-grammatical relations which involve the enunciative shifts. These analysis have led us, as a result, to recognize the shifts of the enunciative categories responsible for compromising the student's text, as well as to identify them as linguistic-statements resources used in the production of meaning in fables texts. In response to overall objectives, we believe that the approach of these issues in the teaching/learning of language can indicate a path so that the pedagogical practices accomplish, geared towards the development of students discursive competence, a task that is objectified by the school.
Estudo experimental e numérico da força de levitação magnética em supercondutores de alta temperatura crítica
(Universidade Federal de São Carlos, 2009-09-30)
Sanchez, Elmer Saavedra
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Moreira, Fernando Manuel Araújo
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https://lattes.cnpq.br/1809254923092721
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https://lattes.cnpq.br/4927164334841312
In this research work we propose, in general, to address the issue of magnetic levitation force between a superconducting material and a permanent magnet. This is a very current and relevant mainly from a technological standpoint, as it allows, among others, the design of machines such as motors, generators and trains based on the principle of levitation. Thus, the research proposed here has been very inclusive, treating the subject of levitation not only from the experimental point of view, but also theoretical. In the experimental approach we have built, assembled and calibrated an experimental station that measures the levitation force, vertically and horizontally, of a permanent magnet on a sample of high critical temperature superconducting materials of the type YBa2Cu3O7-d. Within this scope, we also have developed the ability to prepare the samples using various types of chemical methods and routes that resulted in samples with different textures and properties, where the measurement of the levitation force also pointed out differences between them. The samples had their quality assessed by (a) magnetic characterization (through measures of AC magnetic susceptibility) and (b) structural characterization (through measures of x-rays diffraction and measurements of scanning electron microscopy). In the theoretical approach of this issue, we developed a program allowing simulating the magnetic levitation force by obtaining the relations of force between the permanent magnet and the superconducting material. In this numerical study we have considered the analytical expressions of classical electromagnetism to write the integral equation of the derivative of the current density inside the superconductor, as a function of the geometry and the settings of the applied field. Next, we used the Method of Moments to write the integral equation in its analytical formulation matrix, in which the current density at each point in time is obtained by a simple rule of integration (Euler method). Thus, were also calculated curves for superconducting magnets in the shape of a finite cylinder in which it was measured the levitation force between a permanent magnet and a superconductor, both in the finite and cylindrical geometry. Finally, we compare both results, theoretical and experimental, for sets of samples with different geometries and obtained following different preparation methods.
A sonoridade híbrida de Hermeto Pascoal e a indústria cultural
(Universidade Federal de São Carlos, 2009-09-30)
Silva, Camila Perez da
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Pellegrini, Tânia
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https://lattes.cnpq.br/0280434883580627
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https://lattes.cnpq.br/0169459180378881
This research addresses the sound hybrid developed by Brazilian musician Hermeto Pascoal, in order to understand the influence of technical rationality scattered by the culture industry, as well as the possibilities of resistance against the logic of standardization of the system. The development of a style of composition and the adoption of specific strategies for the dissemination of Hermeto s creations helps to understand the dialectic between the autonomy of the aesthetic subject and the homogenization of the culture industry, and how the very rich tradition and craft of Brazilian music, especially popular instrumental in some respects, it isn t offered as a docile field to economic domination of this system.
Regras de ocupação e influência de dopantes trivalentes em matrizes cerâmicas transparentes de PLZT 9/65/35
(Universidade Federal de São Carlos, 2009-10-01)
Botero, Eriton Rodrigo
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Garcia, Ducinei
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https://lattes.cnpq.br/5236758856687873
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https://lattes.cnpq.br/8529549983857097
In this work, were investigated the occupancy of rare-earth ions in lattice site of the ferroelectric system (Pb,La)(Zr,Ti)O3, or PLZT. The influence on the structural, microestructural, dielectric, ferroelectric, optical and electro-optical properties, due to the aliovalent occupancy were also investigated. The rare-earth oxides (Nd2O3, Ho2O3, Er2O3, Tm2O3 e Yb2O3) were added, at 1.0 weight %, to the ceramic powders of PLZT (with La/Zr/Ti=9/65/35), synthesized by the conventional oxide mixing process, and then were re-calcined. The ceramic bodies, conformed from the milled powders, were densified by uniaxial hot pressing method. The properties of the ceramics were comparatively analyzed as a function of the rare-earth doping ions. The structural characterization, at room temperature, was made using the Rietveld refinement of the XRD patterns. In this way, for each composition, the effective stoichiometry, the lattice parameter and the crystalline symmetry were identified. The occupancy of the rare-earth ions were confirmed in the both, A and B, sites of the PLZT s perovskite structure (ABO3). The ionic occupancy is ruled by its atomic radii, pre-determined by Pauling rules for the structural stability. The effects of the aliovalent ionic occupancy were investigated using a novel parameter, the ―effective radius‖, defined as an average of the radius and the atomic concentration for each coordination number, i.e., a parameter which the geometric characteristic of the ion (ionic radius) and its molar content in each site are considered. In this way, it was observed that dopants with effective radius > 1.2 Å, as the Nd+3, preferentially occupy the A sites of the PLZT s perovskite structure. In this specific case, at room temperature, a cubic crystalline symmetry (paraelectric) was stabilized; a typical quadratic electro-optic effect and a slimloop polarization hysteresis were found. Up to 1.0 weight % of Nd2O3, ~1.9 mol % of Nd+3, were found no formation of segregated phase, that shows the ion stability in the crystalline lattice. The preferential occupancy of the A sites, as also in the case of the Ho+3, have the formation of lattice vacancies in the A sites, as consequence. The effects of these vacancies are the decrease of the polarization values and an increase of the diffusiveness of the phase transition. By the way, for doping ions with effective radius <1Å, as in the case of the Tm+3 and Yb+3, the preferential occupancy in the PLZT s perovskite structure are in the B sites. In such way, oxygen sites vacancies (VO) are originated. For these cases, an increase of the electrical polarization, the ferroelectric fatigue process and the linear electro-optic effect could be observed. In this case, for the doping content of 1.0 weight %, added in the PLZT s matrix, a formation of segregated phase and a consequent reduction the optical transmittance values can be observed. Dopants with intermediary effective radius, as the Er+3, have the lattice occupation in the both (A and B) sites equally divided, and the effects of this class of occupancy are mixed from the two cases discussed. Based on these results, it is proposed one limit for the trivalent ions occupancy in both A/B sites of the perovskite structure of the PLZT 9/65/35, where the effects of aliovalent ion substitution induce different changes in the properties of the ceramics.
Preparação e caracterização de nanocompósitos de LDPE e LDPE/EVA com partículas de Ag/TIO2 para aplicações antimicrobiais
(Universidade Federal de São Carlos, 2009-10-02)
Olyveira, Gabriel Molina de
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Pessan, Luiz Antonio
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https://lattes.cnpq.br/8276650236213537
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https://lattes.cnpq.br/1681746201551274
This study investigated the use of a charger inorganic (titanium dioxide) as a support for silver nanoparticles and evaluated the use of material obtained as filler in polymer for antimicrobial application.Silver nanoparticles-titanium dioxide were synthesized by the reduction method developed by Turkevich, also known as a method of citrate. Therefore, we used three different types of titanium dioxide in the colloidal synthesis and found that nanometer titanium dioxide showed better results for the deposition of silver nanoparticles. Silver Nitrate was reduced by sodium citrate with and without the presence of a surfactant (PVP-Polyvinylpyrrolidone) resulting in a stable suspension of nanoparticles of silver / titanium dioxide. We also tested NH4OH (ammonium hydroxide) to prevent the growth of nanoparticles during the reaction. Nanocomposite of LDPE and LDPE / EVA were produced by mixing in the molten state with the Ag nanoparticles-titanium dioxide resulting from the colloidal synthesis. By assessing the rheological, thermal and morphological analysis we found that compared with nanocomposite LDPE / EVA, LDPE nanocomposite showed better results with regard to dispersion of the charges, but nanocomposite LDPE / EVA showed better results in antimicrobial assays due to the polar nature the grouping of EVA able to bind more easily to inorganic fillers.
Caracterização ótica não-linear em cerâmicas ferroelétricas transparentes (CFT s) de PLZT: TR (TR = nd,Ho, Er, Tm e Yb)
(Universidade Federal de São Carlos, 2009-10-02)
Milton, Flávio Paulo
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Garcia, Ducinei
;
https://lattes.cnpq.br/5236758856687873
Lead titanate zirconate modified with lanthanum, or PLZT, is one the most ferroelectric compounds utilized in electronic devices, due to its versatility and low production costs in comparison with single-crystalline materials. When adequately prepared, this system presents good optical (high optical transmission) properties, in the visible and near infrared range, and can be electro-optically characterized. Recently, in the end of 90 s, it was verified its high potential as host of photoluminescent ions, as the lanthanide (rare-earth) family. The possibility to use its electro-optic properties (due to its ferroelectric characteristics) and its photoluminescent properties (achieved by the doping process) together ,enlarges the range of application of this system. In this way, the electro-optical characterization of doped PLZT ceramics becomes essential, besides the photonic characterization. In this work, the Senarmont compensator method for electro-optical characterization, or dynamic method, was instrumented, and the values of the induced (due to the quadratic electrooptic effect, Kerr) and permanent (due to the linear electro-optic effect, Pockels) birefringence were determined as a function of the temperature, wave-length and electric-field frequency, of the rare-earth (Nd2O3, Ho2O3, Er2O3, Tm2O3 e Yb2O3) doped PLZT, with La/Zr/Ti=9/65/35, ceramics. The results shown a relationship between of the electro-optic (electro-optic coefficients, or birefringence values) and the dielectric, ferroelectric and structural properties (studied in others works) of the ceramics, that were related with the site occupancy and the structural defects due to the aliovalent dopant. It also can be identified two distinct birefringence dependence as a function of the electric field, for the same electro-optic effect (Kerr, or Pockels), identified as a function of the doping process. In the case of electro-optical characterizations in function of the variable frequency, was observed an agreement with the characterization ferroelectric results made in other works in GCFerr, being evidenced the reduction of electro-optical properties with increasing frequency, where if it observed the occurrence of anomalies in the Pockels response with direct influence on the response Kerr. The characterization as a function of wavelength showed the occurrence of two types of behavior depending on the dopant ion used, being one of them the reduction of the values of birefringence with increasing wavelength (the samples pure and doped ions neodymium (Nd) and ytterbium (Yb)), with a tendency to expected behavior in the literature, however, in the second was seen irregular increase birefringence with increase wavelength (for samples doped with ions holmio ( Ho), erbium (Er) and thulium (Tm),not existing relation with to the theoretical models adopted. In relation the characterization as a function of temperature, this was carried through in a temperature interval that understood the characteristic temperatures of systems relaxores (freezing temperature (TF), the maximum dielectric permittivity (TM (e)) and Burns (TB)), except for the sample doped with neodymium ions, whose freezing temperature is below interval worked. By the curve of birefringence (Δn) as a function of temperature was possible to determine the temperature of maximum birefringence for each of the samples, correlated them with each other. Through the curve (d Δn / dt) vs. T was possible to identify a relationship between the maximum variations, positive and negative birefringence with the temperature characteristics TF and TB.
Efeito Aharonov-Bohm: extensões auto-adjuntas e espalhamento
(Universidade Federal de São Carlos, 2009-10-05)
Pereira, Marciano
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Oliveira, César Rogério de
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https://lattes.cnpq.br/5485204156806697
;
https://lattes.cnpq.br/5082255083350460
In this work we present a study of topics related to the Aharonov-Bohm (AB) e®ect. Our framework is that of nonrelativistic quantum mechanics and we use the point of view of mathematical physics. (1) We study the solenoid of finite length and zero radius and compare their self- adjoint extensions with the known case of the solenoid of infinite length and also of zero radius in the plane. (2) By considering an infinitely long cylindrical solenoid of radius greater than zero, mainly in the plane, we present a classification of all self-adjoint SchrÄodinger operators (i.e., the possible boundary conditions on the solenoid border) that mathematically could characterize the AB operator, whose domains are contained in the natural space of twice weakly di®erentiable functions (and, of course, also square integrable). (3) We then consider the traditional Dirichlet, Neumann and Robin boundary conditions on the solenoid border and calculate and compare their scattering matrices and cross sections. Hopefully this could be used to experimentally select one of such extensions. (4) Finally, we discuss a theoretical mechanism we propose to select and so justify the usual AB hamiltonian with Dirichlet boundary conditions on the solenoid. This is obtained by way of increasing sequences of finitely long solenoids together with a natural impermeability procedure; further, it is shown that both limits commute. Such rigorous limits are in the strong resolvent sense.
Quanto vale um talento? Uma análise antropológica sobre a valorização e circulação dos jogadores de futebol profissional no mercado esportivo
(Universidade Federal de São Carlos, 2009-10-13)
Palmiéri, Júlio César Jatobá
;
Toledo, Luiz Henrique de
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https://lattes.cnpq.br/6711269335520497
Preservação de mínimos locais de famílias de funcionais via gama-convergência e aplicações
(Universidade Federal de São Carlos, 2009-10-14)
Pereira, Jamil Viana
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Nascimento, Arnaldo Simal do
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https://lattes.cnpq.br/6609243657130387
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https://lattes.cnpq.br/1641850650875934
Análise da expressão e do papel da ADAM9 humana na capacidade invasiva de células tumorais por silenciamento gênico
(Universidade Federal de São Carlos, 2009-10-14)
Micocci, Kelli Cristina
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Araújo, Heloísa Sobreiro Selistre de
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https://lattes.cnpq.br/4065824911933203
;
https://lattes.cnpq.br/5602101431025314
ADAMs is a term used to describe the presence of disintegrin and metalloprotease domains(A Disintegrin And Metalloprotease) in a certain class of multi-functional membrane proteins,expressed in several animal species such as mammals and insects. They play important rolesin many physiological processes as in fertilization, myoblast fusion, migration, proliferationand cell survival, as well in diseases including breast, prostate, and pancreas cancer. ADAM9is involved in cellular processes such as adhesion, migration and signaling of tumor cells andit is involved in the metastatic spreading. Aims: To analyze the expression of ADAM9 intumor cell lines (MDA-MB-231 and DU-145), no tumors (FH and C2C12), and to generateknockout clones for ADAM9 expression using silencing RNA techniques for the study ofADAM9 effects on invasion, proliferation and gene expression of MDA-MB-231 cells.Methods: Cells were cultured and plated (2x106 cells/plate of 6cm) for 24 hours in DMEM(10% FBS) and lysed for western blotting and zymography. To check for inhibition ofadhesion to immobilized collagen I, MDA-MB-231 cells and FH (5x106 cells/ml) werelabeled with CMFDA, and then incubated with anti-ADAM9D and anti-RP3ADAM9 indifferent concentrations. For ADAM9 silencing, it was used a kit (Silencer ® siRNA StarterKit - Ambion), 2x105 cells (MDA-MB-231) and the transfection agent (Lipofectamine 2000 -Invitrogen). The cells were plated in 5ml of culture medium DMEM/plate. On the third daycells were treated with the transfection agent and RNA silencing primers. Total RNA wasisolated for RT-PCR, and proliferation and invasion in matrigel assays. Results: All the celllines studied expressed ADAM9 in the tested conditions. MMP-2 (Gelatinase-A) activity wasdetected in the cell extracts of all studied cell lines. Silencing of ADAM9 did not affect therate of MDA-MB-231 proliferation, at 4, 5, 6, 7, 8, 9 and 10 days after silencing (24 or 48hours of incubation in 96-well plates). Silencing of human ADAM9 inhibited tumor cellinvasion in matrigel (71,51±8,02%) when compared to control. Conclusion: The generation ofMDA-MB-231 knockout clones lacking ADAM9 expression using siRNA technique did notaffect the rate of cell proliferation but inhibited tumor cell matrigel invasion, suggesting thatADAM9 is an important molecule in the processes of invasion and metastasis.
Estabelecimento de meios de cultura para o cultivo de Streptomyces isolados de sedimento marinho
(Universidade Federal de São Carlos, 2009-10-16)
Romano, Luis Henrique
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Sousa, Cristina Paiva de
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https://lattes.cnpq.br/9002619114161319
;
https://lattes.cnpq.br/0692713353762468
Microorganisms represent an important source for production of bioactive metabolites for diverse applications. The production of these substances is directly related to the culture medium associated with sources of carbon and nitrogen available. Thus this study aimed to establish an appropriate composition of culture media for growth of Streptomyces carpaticus, Streptomyces acrimycini and Streptomyces cebimarensis. These microorganisms were isolated from marine sediments that were preserved in cryovials stored at-80ºC. The species studied were grown on solid media ISP4, ISP5 and GYM and phenotypically characterized. It was observed that Streptomyces carpaticus developed uniformly in all culture media and presented production of pigment in Gym medium. Microorganisms were also grown in solid media (Gym, A1RDP, ISP4 and ISP5). It was observed that Gym is the best medium to promote the microorganism growth. The strains were grown in different concentrations on osmotic medium Gym and on minimal medium with different sources of carbon and nitrogen in crops with flasks. The three strains were grown in batch bioreactors using conventional Gym medium and it was obtained 4 g / L of cell mass of S. carpaticus and S. acrymicini and 6 g / L of cell mass of S. cebimarensis. It was observed the presence of substances with cytotoxic activity on the breeding grounds. Besides, it was observed that the three species probably present diauxic behavior. S. carpaticus consumed preferentially maltose, while other species used glucose first.