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O efeito Casimir dinâmico e decoerência
(Universidade Federal de São Carlos, 2008-07-03)
Céleri, Lucas Chibebe
;
Moussa, Miled Hassan Youssef
;
https://lattes.cnpq.br/7828776012924524
;
https://lattes.cnpq.br/6630683190018665
In this thesis we first demonstrate that the inevitable action of the environment can be substantially weakened when considering appropriate nonstationary quantum systems. Beyond protecting quantum states against decoherence, an oscillating frequency can be engineered to make the system-reservoir coupling almost negligible. Differently from the program for engineering reservoir and similarly to the schemes for dynamical decoupling of open quantum systems, our technique does not require a previous knowledge of the state to be protected. However, differently from the previously-reported schemes for dynamical decoupling, our technique does not rely on the availability of tailored external pulses acting faster than the shortest time scale accessible to the reservoir degree of freedom. We show, in the domain of cavity quantum electrodynamics, how to engineer such a nonstationary cavity mode through its dispersive interaction with a driven two-level atom. Next, we consider different aspects of the dynamical Casimir effect (DCE) through the derivation of effective Hamiltonians which exhibit the essential features of the phenomenon. We start by investigating the dynamical Casimir effect in a nonideal cavity at finite temperature. We first compute a general expression for the average number of particle creation, applicable for any law of motion of the cavity boundary. We also compute a general expression for the linear entropy of an arbitrary state prepared in a selected mode, also applicable for any law of motion of the cavity boundary. As an application of our results we have analyzed both the average number of particle creation and linear entropy within a particular oscillatory motion of the cavity boundary. On the basis of these expressions we develop a comprehensive analysis of the resonances in the number of particle creation in the nonideal dynamical Casimir effect. We also demonstrate the occurrence of resonances in the loss of purity of the initial state and estimate the decoherence times associated with these resonances. We also consider the dynamical Casimir effect for a massless scalar field, under Dirichlet boundary conditions, between two concentric spherical shells. We obtain a general expression for vii the average number of particle creation, for an arbitrary law of radial motion of the spherical shells, using two distinct methods: by computing the density operator of the system and by calculating the Bogoliubov coefficients. We apply our general expression to breathing modes: when only one of the shells oscillates and when both shells oscillate in or out of phase. We also analyze the number of particle production and compare it with the results for the case of plane geometry. Finally, we analyze the action of the gravitational field on the dynamical Casimir effect. We consider a massless scalar field confined in a cuboid cavity placed in a gravitational field described by a static and diagonal metric. With one of the plane mirrors of the cavity allowed to move, we compute the average number of particles created inside the cavity by means of the Bogoliubov coefficients computed through perturbative expansions. We apply our result to the case of an oscillatory motion of the mirror, considering a weak gravitational field described by the Schwarzschild metric. The regime of parametric amplification is detailed analyzed, demonstrating that our computed result, for the mean number of particles created, is in agreement with associated particular cases in literature.
Macroinvertebrados em córregos de baixa ordem sob diferentes usos do solo no estado de São Paulo: subsídios para o biomonitoramento
(Universidade Federal de São Carlos, 2008-07-04)
Suriano, Marcia Thais
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Gessner, Alaíde Aparecida Fonseca
;
https://lattes.cnpq.br/846575283652970
;
https://lattes.cnpq.br/7544344533006589
The environmental monitoring assesses the state of preservation of aquatic ecosystems, providing information for the development of strategies for management, conservation of natural areas and plans for recovery of degraded environments. This evaluation is performed through abiotic and biotic information, in particular the macroinvertebrates. This work focused on this biota to evaluate the environmental quality of low order streams in the State of Sao Paulo using two approaches: the community structure and the selection of multimetrics. The first approach presents the study of the taxonomic composition and the structure of functional feeding groups of benthic macroinvertebrates, and the second concerns the selection of metrics applied to this community to assess the integrity of lotic environments. We selected 29 streams of 1st and 2nd orders in different landscape and land uses, of which 15 streams are located in the following Conservation Units: Parque Estadual de Campos do Jordão, Estação Ecológica de Caetetus, Parque Estadual Furnas do Bom Jesus, Parque Estadual de Vassununga, Parque Estadual do Morro do Diabo e Parque Estadual de Intervales, and 14 are located in regions with sugar cane, eucalyptus and pasture monocultures. The environmental characterization followed the protocol proposed by the Project Biota/Fapesp and is detailed in Material and Methods. In each stream we delimited a segment of 100m and took six samples of benthic fauna using a Surber sampler. The identification was made until the lowest practical taxonomic level using keys for identification, original descriptions and help of experts when needed. For the first approach, the results showed differences in the taxonomic composition and structure of functional feeding groups among the streams and the areas with different land uses. In general, there was greater participation of Trichoptera, Ephemeroptera, Plecoptera and Coleoptera in streams located in the Conservation Units and greater participation of Odonata, Diptera, Bivalvia and Gastropoda in streams located in impacted areas. The analyses of the functional feeding structure showed that the shredders were major participatants in areas with riparian vegetation including two streams located in eucalyptus monoculture. To assess the integrity of low order streams in the State of Sao Paulo we selected 51 metrics which were analyzed using the following criteria: i, predictable response to the anthropic impacts, ii, higher taxonomic resolution, iii, operational and theoretical simplicity. Eighteen metric were related to the environmental and spacial predictors used. Of these, eight metrics covered the selection criteria set and were potentially considered to integrate a multimetric system for evaluating low order streams of the State of Sao Paulo: taxonomic richness of family, total of richness Ephemeroptera, Plecoptera and Trichoptera, total density of specimens, percentage of Megaloptera and Hirudinea groups, percentage of Ephemeroptera, Plecoptera and Trichoptera groups together, the Shannon diversity index for genera and the adapted BMWP index.
Análise qualitativa de um projeto com uma família de agricultores no assentamento rural Fazenda Pirituba II
(Universidade Federal de São Carlos, 2008-07-04)
Carvalho, Carolina Delgado de
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Ferraz, José Maria Gusman
;
https://lattes.cnpq.br/3851804858390996
;
https://lattes.cnpq.br/0466296477808368
Agroecology emerges as a science in the 70´s of the 20th century. It criticizes convencional agriculture based on a paradigm that passes over social individual connected to natural resources management what brings up serious social and environmental consequences. It proposes an alternative to the subject division of positivist science and incorporates social and ecological view in the agricultural systems analysis. It has a pluri-epistemological nature and makes use of participative metodology with a perspective of dialetics research, breaking up with subject-object power structure of convencional science that says investigator is who knows and the individuals are objects to be analysed. This work tries to break up with this power relationship and to give voice to a family of agriculturists participating in a project developed by Incubadora Regional de Cooperativas Populares (INCOOP/UFSCar) in the Fazenda Pirituba II Rural Settlement. Its purpose is to analyse the agroecological transition this family is passing through and that this project is part of. For it qualitative research methods were used like participant observation, case study and oral life history. Institution disconnection, non-comprehension of the socialhistorical context, loss of global view and leaving off project seemed to be the main factors contributing to the project failure. We conclude that longer supported projects articulating governamental, non-governamental institutions actions and agriculturists supported by an efficient Agroecological Rural Extension public policy must contribute to generate sustainable and autonomous processes in the communities.
Aspectos fisioecológicos de Astyanax fasciatus e Pimelodus maculatus (teleósteos) do reservatório da UHE de Furnas, MG: avaliação morfofuncional das brânquias e variáveis hematológicas
(Universidade Federal de São Carlos, 2008-07-04)
Henrique, Helen Sadauskas
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Fernandes, Marisa Narciso
;
https://lattes.cnpq.br/3021357484136942
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https://lattes.cnpq.br/1910990054248099
The aim of this study was to evaluate the morphofunctional structure of the gills and the hematological variables of Astyanax fasciatus and Pimelodus maculatus living on Furnas Dam Reservoir (Minas Gerais State, Brazil) and analyses the influence of water quality on these parameters. The fishes were collected in five sites (FU10: Turvo; FU20: Guapé; FU30: Barranco Alto; FU40: Fama and FU50: Porto Fernandes) during June and December/2006. Physico-chemical variables and organochlorides content of the water and heavy metals on the sediment were performed. Gills and blood samples were taken for check inquire of the composition of the water on the presence of histopathologys and differentiation of chloride and mucous cells and differences on the hematological variables of the fishes collected on the different sites. Hyperplasia and hypertrophy of the respiratory epithelium, lamellar fusion, epithelial lifting, oedema and chloride cells proliferation were the most common histopathological damages observed on the gills for both species. The histopathological alteration index of the gills indicates some degree of lesions that engage the normal function of the organ in A. fasciatus collected in June. Heavy metals, as copper seems to promote alterations on the red blood cells for both fishes during the sampling. While, some pollutants as endosulfan, metolachloride, copper and chromium seems to causes a stimulation of the immune system of the fishes; this effect was most common on the fishes collected in the sites: FU10, FU20 and FU30. The condition factor (K and Kn) of the fishes has been affected by the presence of chromium on the sediment, especially in the site FU30 during the two months. Over all, these results indicates that the water quality in June and December (2006) of Furnas Dam reservoir could promote physiological and morphological alterations on the gills fishes to maintain the homeostase.
Análise da gestão de cooperativas rurais tradicionais e populares : estudo de casos na Cocamar e Copavi
(Universidade Federal de São Carlos, 2008-07-04)
Chiariello, Caio Luis
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Eid, Farid
;
https://lattes.cnpq.br/6858881569501075
Led back to the center of the politician debate since 1970 s, the liberal speech affirms that the economic development proportionated by the global market is enough to solve workers unemployment. In this context, liberals defend that the association of workers in cooperatives is functional to the capitalism, brightening up social effects of the cyclical crises of production, losing its function when of the increase of the production, and soon of the job. So, cooperatives would appropriate of the technical instruments of management from typically capitalist companies and would evolve to become capital valuation spaces. In the Brazilian case, this conception bases the theoretical reflection about the necessity of the traditional agricultural cooperatives to seem its management in the great participant companies of the agribusiness, adhering to the postulates of economic rationality, searching for profit. This text presents the case study on a traditional agricultural cooperative with this profile, the Cooperative COCAMAR, identificated with capital companies. On the other hand, in Brazil, since 1990 s, many workers started organizing themselves democratically in solidary economic enterprises. They ve searched for job and struggled with unemployment, intending the continuity of their activities, subordinating the economic rationality to the social rationality. Popular cooperatives are some of these enterprises, originated from social movements of resistance, worried in offering better conditions of life to the associates. One of the main challenges of these popular cooperatives is the adoption of management tools that make possible greater effectiveness in the production and permit their permanence in the market, but not compromising its solidary principles. This text also presents a case study done on the Cooperative - COPAVI, each was founded by no land workers of MST. Through the empirical inquiry, we ve analyzed some management elements: the collective property of the land and the means of production; the access to the credit under differentiated conditions; the search for an effective internal democracy and organization of work under the self management, taken as fundamental to COPAVI exerts its activities into the capitalism, but not omitting its solidary principles and its character of social movement.
Descentralização e gestão participativa dos recursos hídricos: dois estudos de caso em bacias hidrográficas do médio Tietê
(Universidade Federal de São Carlos, 2008-07-07)
Miranda, Cristiani Olga
;
Vargas, Marcelo Coutinho
Abstract This work had as objective the analysis of the ways and the dynamic of civil society participation on the water resources management in the State of São Paulo. Advocated on the state legislation that established the Water Resources Management Integrated System, the participation of civil society organized entities is considered one of the main fundaments of water resources state policy and system, created by the law 7663/91, that are explicit oriented by a model of integrated, decentralized and participative management of the water. The bases of the management system are the hydrographical basin committees: deliberative commissions with three kinds of representation, with equal participation of state government, local prefectures and organized civil society of the region. The water resources management in the State of São Paulo can be seen as a propelling focus of changes in the public administration, because this sector organization advances in the direction of a participative democracy, articulating governments and civil society in more transparent decision structures, representing the different interests, searching to guarantee the conflicts regulation and the governance of complex aspects of the actual socioenvironmental dynamic. In the actual model of the water resources institutional organization, the participation is understood as an instrument to make feasible and legitimize the intervenient public policies. However, it s possible that the effective participation of civil society is merely punctual and restricted, because it depends of the decentralized actions of regulation in the scope of each committee and other favorable conditions. Based on interviews, bibliographical, documental and field research, combined with the accompaniment of the actuation of Piracicaba/Capivari/Jundiaí and Tietê/Jacaré Basin Committees, it was intended to characterize the civil society participation on these forums, analyzing the main actors involved, its ways and channels of action. On this perspective, the results suggests important institutional innovations on environmental public policies, but indicates that the participative process don t exclude the imbalance of institutional forces and arrangement, which can undermine the participative democracy principle on the Hydrographical Basins Committees.
Estudo das propriedades reológicas de nanocompósitos para a produção de filmes tubulares
(Universidade Federal de São Carlos, 2008-07-08)
Beatrice, Cesar Augusto Gonçalves
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Bretas, Rosario Elida Suman
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https://lattes.cnpq.br/2805349172281345
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https://lattes.cnpq.br/6023179925944867
In this work, the use of rheological measurements in substitution or complementation to methods normally employed in the characterization of nanocomposites, such as X-ray diffraction (WAXS) and transmission electron microscopy (TEM), was evaluated. Two polymeric matrices with different chemical structures and polarities and two organophilic nanoclays modified with organic surfactants, which were compatible with the respective polymer matrix, were used. Thus, polyamide 6 (PA6) and high density polyethylene (HDPE) nanocomposites were obtained by melt mixing and blown as films. WAXS measurements showed intercalated structures in the HDPE nanocomposites and exfoliated structures in the PA6 nanocomposites. Shear oscillatory rheological experiments were done to evaluate the clay dispersion and distribution in the polymer matrices, which indicated the presence of a poor dispersion in the HDPE nanocomposites, differently of the PA6 nanocomposites. Shear steady and transient rheological measurements indicated that higher interactions between PA6 and the nanoclay modified with a polar surfactant and inside the EVA masterbatches occurred. From the rheological, morphological, mechanical and transport analysis it was found that the addition of clay modified the interfacial interactions between HDPE and EVA, increasing the system compatibility. In both systems, there was an increase in elastic modulus, yielding and rupture behaviors and barrier properties. In conclusion, the rheological characterization of nanocomposites provides further information about the nanoclay dispersion and distribution in the polymer matrix, in addition to quantify the interactions between the components. However, it can not substitute the usual methods of characterization of the nanocomposites, such as WAXS and TEM.
Desenvolvimento de painel pré-fabricado em alvenaria protendida
(Universidade Federal de São Carlos, 2008-07-08)
Souza, Paulo Roberto Amaral
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Parsekian, Guilherme Aris
;
https://lattes.cnpq.br/7798651726059215
This research aims the development of a clay block post-tensioned masonry façade panels, as a new alternative building process. This process provides technical and economic advantages when compared to other process in the market. It presented an analysis of the design of the wall and the process of execution of this type of panels for its use as spandrel panels. Initially the technology of prestressed structural masonry and the systems of precast panels façade are presented to establish the concepts and basic guidelines for the development of this research. The proposed panels building process were tested experimentally with the production of three prototypes, designed for their use as horizontal façade panels. Tests were performed in which the panels were supported at the ends with its self weight and additional mid-span load applied simulating the action of horizontal out-of-plane loading in façades. The experimental tests indicate that the post-tensioned masonry panels have excellent structural behaviour, carrying more load then those estimated in the theoretical analysis, thus proving the full viability of execution and use of this type of panel.
Caracterização genética de populações de jaú (Siluriformes: Pimelodidae) utilizando marcadores moleculares mitocondriais e nucleares
(Universidade Federal de São Carlos, 2008-07-08)
Avila, Mauricio Carrillo
;
Galetti Júnior, Pedro Manoel
;
https://lattes.cnpq.br/3722377660974573
The genus Zungaro known as jaú, is composed by two species distributed along the rivers of South America: Zungaro jahu is found further south in the basin of the Paraná-Paraguay whereas Zungaro zungaro is found further north in the basin of the rivers Amazon and Orinoco. However, in the literature the classification and distribution of each of those species is still unclear and the basic information on the biology and natural history is scarce. In Brazil the jaú is listed as one of endangered species, over-exploited or threatened by overexploitation; however, the regulations fail to protect the jaú because they have mistakenly identified it as Zungaro zungaro. In Colombia, according to the freshwater species Red Book, the Zungaro zungaro has been declared endangered. Considering the limited information on the population genetics of these fish, the purpose of this study was to obtain the genetic characterization of the jaú population through mitochondrial and nuclear molecular markers. This purpose includes the following research questions: 1- Given the uncertainties encountered in the taxonomic genus Zungaro, is this group composed by two species, or are they two different populations? 2- Considering the jaú´s big size and the fact that they migrate long distances, would than mean that there is a population structure? and 3- The jaú´s endangered condition, its habitat´s changes and overfishing, could be responsible for a reduction of the genetic variation of these catfishes? In order to conduct the characterization we used molecular markers such as the mitochondrial cytochrome b gene, the nuclear gene RAG (Recombination Activation Gene) and the nuclear gene coding for ribosomal protein S7. Additionally, a total of eight polymorphic microsatellite loci capable of producing a considerable genetic variation was prospected. The population analysis of the genus Zungaro with mitochondrial and nuclear markers indicated the existence of a population structure among the individuals sampled. This result is due mainly to the differences between the populations of Pantanal - Paraná and the populations of Meta and Amazon; this finding supports the separation of these species. It was also found that these populations share a central haplotype, indicating a genetic cohesion in the genus, where the populations of Meta-Amazon had a greater number of derived haplotypes suggesting a possible population expansion. The occurrence of a unique and central haplotype to the populations of Pantanal- Parana from which the haplotypes of Meta and the Amazon are derived, when the gene RAG was used, would support the idea that these populations would be the center of dispersion and they would retain the ancestral haplotype. Regarding the prospected microsatellite loci, the results indicated they were efficient in the amplification and verification of polymorphism in Zungaro jahu, and were effective in heterologous amplification of other species of the Pimelodidae family. Statistical analyses on the microsatellites loci showed evidence of a single population of the Z jahu specie inhabiting the north and south Pantanal. In contrast, the two Z zungaro populations studied (the Meta River, basin of the Orinoco and the Amazon River) shown to be significantly different, indicating a population structure. In spite of the jaú being an endangered species, the results of the genetic variation showed values comparable to other species of fish. These results open the possibility of developing clear management programs specifically directed to each of these populations, seeking the protection and recovery of individual fish stocks.
Fração de filme líquido nas paredes de um lavador Venturi
(Universidade Federal de São Carlos, 2008-07-10)
Daher, Maristela de Almeida Felício
;
Coury, José Renato
;
https://lattes.cnpq.br/4502024143494992
The study of the liquid film in the walls of a Venturi scrubber was chosen as the target of this work for representing one of the important phenomena that influence the collection efficiency of the equipment. Such efficiency decreases with the presence of the film once it has a superficial area per volume much smaller than the drops and, consequently, contributes very little in the removal of particles. Furthermore, the pressure drop on the Venturi depends on the energy spent to accelerate the drops and also of the attrition between the gas and the surface of the film. These two important parameters depend on the liquid fraction in the form of film. For these reasons, it is important for the project of Venturi scrubbers the quantification of the film fraction. The present work, therefore, carried out an experimental investigation of the effects that the liquid injection through multiple jets exerted in the formation of the liquid film in a Venturi scrubber of rectangular cross section. The behavior of the fraction of liquid film in each wall separately and of the total fraction of liquid film extracted were analyzed, varying the liquid flow rate from 0,3 to 1,2 l/min for gas velocities of 59, 64, 69 and 74 m/s. Throat lengths of 100, 160 and 220 mm were utilized. The results showed that the film fraction varies with the gas velocity, with the configuration of the liquid injection, with the liquid flow rate and with the axial distances along the throat. The analysis of the film extraction in the individual walls follows an asymmetric behavior in all operational conditions, showing a larger film deposition in the inferior wall independently of the injection configuration, thus indicating the effect of the gravity in the film deposition. Hence, the total fraction of liquid extracted from the four walls of the scrubber made possible a more satisfactory interpretation of the results. Within the experimental range investigated, the injection through four orifices at the gas velocity of 74 m/s at the higher liquid flow rates presented the smaller deposition of liquid in the scrubber walls. It was also evident that the deposition is dependent on the penetration of the jet: low penetrations tend to deposit in the jet injection wall while high penetrations deposit in the opposite wall. There is, therefore, a point of minimum deposition for the intermediate penetration of the jet. The best operational conditions, i.e. the smallest film fraction deposited in the walls, was obtained for the largest gas velocity and for the liquid being injected simultaneously through the four walls.
Inteligência computacional aplicada à automação de biorreator para produção de Penicilina G Acilase (PGA)
(Universidade Federal de São Carlos, 2008-07-11)
Fernandes, Pedro Luiz
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Giordano, Roberto de Campos
;
https://lattes.cnpq.br/0834668419587001
;
https://lattes.cnpq.br/6037526193877152
Biotechnology has presented, in the last years, a rapidly growing development. New biotechnological industrial processes are constantly introduced using different microorganisms and/or enzymes. In this context, the application of process control and optimization techniques has become a need for biotechnological based industry. A technological approach was developed in this dissertation to bioreactor monitoring and control operating in fed-batch model to produce the penicillin enzyme G acilase (PGA) by means of wild cepa of the microorganism Bacillus megaterium. This enzyme is of great industrial importance, being used in the manufacture of semi-synthetic β-lactamic antibiotics. This case study presents the main difficulties faced in the control of biological processes in general: the variability of kinetic parameters and the limited availability of on-line information. In order overcome these difficulties, a unconventional architecture was proposed for a dynamic and adaptive controller using filters, some of them developed in this work, and applying Computational Intelligence (CI) methodologies both in direct and hybrid form. The inference for the microbial concentration (Cx) state variable, a very relevant objective for the logic of the controller, was performed by a softsensor that had as input the filtered values of the sensors signals of the molar fractions of CO2 (yco2) and O2 (yo2) in the effluent gases, of the air feeding flow and of agitation velocity. The respiratory quotient (RQ), calculated from these data, was also used by the algorithms of the software developed here. For the Cx inference, the softsensor employed a hybrid intelligent system (HIS) composed by a neural networks ensemble (RNE) and a fuzzy rule based system (FRBS). These techniques were structured to complement each other such that the RNE infers the microbial concentration (Cx) capturing real-time process data (empirical knowledge) and the FRBS corrects this inferred value using phenomenological based knowledge. The obtained results demonstrated a more robust inference by using this architecture, even supporting some degree of extrapolation. Another important operational parameter is the definition of the initial and final instants of feeding flow of supplemental. In order to meet this goal, a logic was employed that is able to accurately predict this moments, using the CO2 (yco2) molar fraction signal, filters and adaptive fuzzy sets.
A geratividade do comportamento verbal : divergências entre as propostas de B. F. Skinner e N. Chomsky
(Universidade Federal de São Carlos, 2008-07-14)
Bandini, Carmen Silvia Motta
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Rose, Julio Cesar Coelho de
;
https://lattes.cnpq.br/3386857761295187
One of the most interesting questions in the study of the language is its original character. Any philosophy or science that tries to explain language must account for this peculiar characteristic. Radical Behaviorism of B. F. Skinner and the theory of Generative-Transformational Grammar of N. Chomsky were very important sources of explanation of language phenomena during the 20th Century. Chomsky was one of the most famous critics of Skinnerian behaviorism. His review of Skinner s Verbal Behavior was probably more known around the world than Skinner s original book. In this review, Chomsky asserts that the operant model can not explain the original character of language. However, recent works have shown that Skinner tries to consider this characteristic when he talks about language. Within this context, the present dissertation intended to investigate Skinner s treatment of the creative processes of verbal behavior, set against Chomsky's theory. This work also tried to search the conceptual categories used by Chomsky to criticize Skinner and use this conceptual categories to improve the analysis of Skinner s text. In addition, this dissertation also attempted an internal analysis of Skinnerian concepts involved in the explanation of verbal behavior, as well as an assessment of the truth or falseness of Chomsky s critical work. We found three conceptual categories used by Chomsky in his Review of Skinner s Verbal Behavior. The survey of such categories allowed a fruitful analysis of Skinnerian account of the generative character of verbal behavior. It is argued that Chomsky committed many conceptual mistakes in his Review and because of these mistakes his work cannot prove that Skinnerian analysis of verbal generativity is impracticable. It is also argued that Skinnerian theory about verbal (and not verbal) generativity does not seem to be in any contradiction to the philosophy of science that Skinner adopts. We then conclude that, from the theoretical standpoint, the behaviorist explanation of verbal behavior and its generativity can configure an useful model.
Desenvolvimento de um fotômetro portátil usando LED como fotodetector e de procedimentos analíticos automáticos empregando multicomutação em fluxo
(Universidade Federal de São Carlos, 2008-07-16)
Silva, Milton Batista da
;
Reis, Boaventura Freire dos
;
https://lattes.cnpq.br/7619359855870896
;
https://lattes.cnpq.br/4056099092803481
This work involves the development of portable photometer using a LED (Light Emitting Diode) as source of electromagnetic radiation and another one LED as photodetector. The viability of this proposal was demonstrated in an automatic photometric titration procedure, which was implemented based on the binary search process. The sensitivity improvement of the classic analytical methods to improve limit of detention is a current demand of the analytical chemistry, to attain the maximum limits established by the regulatory agencies. In photometric detention a resource to attain this requirement would be the increasing of the optical path of the flow cell. In flow analysis, the geometry of the usual cells flow does not allow the increase of the pathlength. The availability in the market of LED with emission beam high intensity within narrow angle of scattering, allows its use to develop homemade photometer. In this work, a LED with this characteristic was used to allowed the use a flow cell with optical path of 200 mm. The flow cell was designed with geometry appropriate to allow the direct coupling of radiation source (LED) and photodetector. According to CONAMA (National Advice of the Environment), orthophosphate is the chemical species that the maximum concentration allowed in fresh water is in the order of g L-1 level. The use of flow cell with optical path of 200 mm was evaluated in an automatic procedure for determination of orthophosphate in waters. The procedure was implemented using the multicommutation flow injection analysis process, using the photometric method based on the reaction with ammonium molybdate and reduction with stannous chloride. Different photodetectors have been employed in prototypes of photometers, thus aiming to compare the performance of the usually employed photodetectors, a set of experiments was carried out, submitting the photodetectors to the same work conditions. The photometric determination of orthophosphate in waters was selected as model to test the response of the used photodetectors.
Atividade inseticida de espécies de trichilia frente à lagarta-do-cartucho do milho spodoptera frugiperda
(Universidade Federal de São Carlos, 2008-07-18)
Nebo, Liliane
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Vieira, Paulo Cezar
;
https://lattes.cnpq.br/8923844563320377
;
https://lattes.cnpq.br/6724147949765463
This work presents the phytochemical study and biological assays carried out with organic extracts of fruits and seeds from Trichilia claussenii, T. elegans and inflorescence from T. catigua against S. frugiperda. Among the extracts assayed, the methanol extracts of seeds from T. claussenii and inflorescence from T. catigua presented the highest insecticidal activity, with 64,0 and 64,4 % of mortality, respectively. The bioassay-guided study of the methanol extract of seeds from T. claussenii led to identification of ��-phenylalkyl and alkenyl fatty acids, active substances in this extract. The flavonoid ent-catequin was isolated from the methanol extract of inflorescence from T. catigua and it was associated with the insecticidal activity found in this extract. Fatty acids with the methylene chains ranging from C-5 to C-16 were assayed against S. frugiperda. Tests showed that the hexanoic, nonanoic and decanoic acids, displayed the highest rate of mortality at concentration of 10,0 mg/mL. The study of the three species allowed isolating and identifying the following compounds: a mixture of ��-phenylalkyl and alkenyl fatty acids, ��-lactonas, 4-hydroxy-N-methylproline, N-methylproline, uridine, uracile, entcatequin, 5-O-cafeoylquinic acid and the steroids 3-��-O-��-Dglucopyranosilsitosterol, ��-sitosterol, campesterol, estigmasterol e sitostenone. The limonoids 11��-acetoxyobacunone and 1,2-dihiyro-1��-acetoxy-11��-acetoxy-14,15-epoxycneorin R were isolated for the first time from a Trichilia species.
Modificação superficial de óxidos : proposta de um modelo simples e sua aplicação em sistema aluminazircônia
(Universidade Federal de São Carlos, 2008-07-18)
Dalmaschio, Cleocir José
;
Leite, Edson Roberto
;
https://lattes.cnpq.br/1025598529469393
;
https://lattes.cnpq.br/5209978120430790
In this study a model that makes possible to foresee the limit of modifier oxide of surface that results in the complete support coating with a unit cells monolayer was proposed. From such limit, the lattice of the modifying material should be formed. According to the proposal, the identification of the crystalline phase of the modifier for coating levels lower than the delimited can be an indication that the deposition method adopted does not result in high dispersion. The model s applicability was demonstrated in aluminas coating with zirconium oxide by using a resin obtained through the polymeric precursors method for dispersion of modifier. The characterization results for X-ray diffraction (DRX) presented excellent correlation with the diagram built from the model. Concentrations maps obtained by energy dispersive x-ray spectroscopy (EDS) evidenced that the modifier deposition occurs on the support. Through high resolution transmission electron microscopy (HRTEM) analysis a monophase material (alumina) without indication of amorphous phase was observed below the saturation limit. Above the limit, two different lattice parameters were observed in the images, being one associated to the alumina and other to the tetragonal zirconium oxide. X-ray photoelectron spectroscopy (XPS) analyses proved that the increase in the zirconium oxide concentration is accompanied by enrichment of the surface by the modifier due to the coating formation. With this technique a strong support-coating interaction, with formation of Al-O-Zr bonds, was also detected. X-ray absorption spectroscopy (XAS) analyses reinforced the argument that the lattice was formed for concentrations above the saturation limit proposed in the model. A better dispersion was evidenced using multiple steps for dispersion of the modifier. Zeta potential measurements indicated attractive interactions more intense between support and resin than between modifier and resin, which explain the better dispersion possible when multiple steps were used.
O que é, o que é?: um ambiente de co-autoria de jogos educacionais baseados em cartas contextualizadas usando conhecimento de senso comum
(Universidade Federal de São Carlos, 2008-07-21)
Pereira, Eliane Nascimento
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Silva, Junia Coutinho Anacleto
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https://lattes.cnpq.br/6200743168568684
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https://lattes.cnpq.br/1779566969221196
Computer use as a mediating tool in education has been discussed and researched in different areas. The aims are to promote knowledge building, to motivate and to engage students and teachers in it. It also increases their digital literacy. However, several factors should be considered in implementing computers at school, for instance, how to involve teachers so they accept computer to change how they teach. Teachers training program should aim at helping them to include computer in their class activities and also to help them to choose software suitable to pedagogic aims defined in school syllabus. This research fulfills the latter aim concerning developing and evaluating an online system which allows teachers to be co-author of an educational online game. Teachers can contextualize it to students' reality, exploring the transversal themes proposed in the Parameters National Syllabus Standards for primary education, allowing teachers to create, even if partially, a computer tool to promote significant learning or to reinforce concepts presented in class. The content card is an outcome of the use of a filtering process of a semantic net generated from the knowledge base of common sense of the Open Mind Common Sense Brasil (OMCS-Br) project. To accomplish the research aims, a step-by-step guide was developed to help teachers to elaborate of the game content. This online game is a guessing game based on contextualized cards, which request players to discover which is secret word from a specific given topic, using some clues presented to him. This game system was developed according to international usability parameters. Then an evaluation test was conducted to evaluate users' satisfaction (in this case specific teachers and students) when they interacted with the game system. In general it can be considered objectives were fulfilled. First, a game system was developed integrated knowledge base. Second, evaluation test reported teachers satisfaction in being co-author a computer game for their students and students are looking forward to using this computer game as support to pedagogic activities at school.
Estudo da fusão de superfície da prata por dinâmica molecular
(Universidade Federal de São Carlos, 2008-07-23)
Gonçalves, Luis Gustavo Vieira
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Rino, José Pedro
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https://lattes.cnpq.br/6801067322823031
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https://lattes.cnpq.br/6801297606724628
A study about surface melting on silver using equilibrium molecular dynamics simulation is the proposal of this work. We applied the Embedded Atom Method as the many-body interaction potential to describe Ag properties. Simulations were done in the microcanonical ensemble, for the study of bulk properties, and in the canonical ensemble, for simulations of the solid with surfaces. As a preliminary result, we obtained the equilibrium melting point Tm equal 1264(12)K from solid-liquid coexistence configurations. Surfaces were simulated using repeated slabs separated by vacuum in the z direction, while keeping periodic boundary conditions in the remaining directions. Results showed that Ag[110] is the lone orientation that has surface melting. Ag[111] maintains its crystalline structure even after reaching Tm, while it could be overheated by 100K. Other properties like density of states, thermal expansion and surface relaxation were in good agreement with experimental data.
Caracterização genética e biométrica das populações de camarão rosa Farfantepenaeus brasiliensis de três localidades da costa do Rio Grande do Norte
(Universidade Federal de São Carlos, 2008-07-25)
Pinheiro, Allysson Pontes
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Galetti Júnior, Pedro Manoel
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https://lattes.cnpq.br/7398754661670478
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https://lattes.cnpq.br/6694712411033380
Shrimp catch is one of the main fishing activities in the world, mostly for the high value of commercialization reached by shrimp meat. Biological characteristics of penaeids make this group of shrimps aspirant to show different levels of population structure. Penaeid species like Farfantepenaeus brasiliensis are dependent of the estuary to complete its life cycle. Thus, the aim of this work was to evaluate if populations of F. brasiliensis, from the coast of Rio Grande do Norte, are structured by morphometrical and molecular analysis. Several measurements (Lt, Lc, La and weight) were recorded for each specimen. Divergence between places has been evaluated by univariate (ANOVA) and multivaried (Discriminant Analysis) techniques. FSTAT and GENEPOP were used to get the molecular levels of genetic variability in each population, as well as, comparisons between populations. The frequentist and bayesian methods were used to detect migrants in GENECLASS software. The results of the 3 morphometric analysis pointed out differences between sex-ratio in all analyzed localities. These results probably are related with differences in growth rate between sex and/or spatial stratification. Significant morphometric differences were obtained between populations by the univariate and multivaried methods. These differences could be consequence of the estuary necessity to complete the life cycle in F. brasiliensis. Likewise, local differences could contribute for these results. Females were more divergent among different areas than males. This result also could be a reflex of the biological characteristics of this species, due to the great relation between the spawning places and the females. The interval between insemination and spawning in shrimp females can be of 10 to 20 days. The molecular results showed medium levels of genetic variability in the analyzed localities. When compared with other species from the same family Ho varied between 0,471 and 0,540. The FST values did not showed genetic structure. However, these results could reflect the low number of analyzed loci, or the predominance of females in the samples, a characteristic inherent of the penaeids. The procedure used to detect migrants did not support the existence of migrants among evaluated populations; however some individuals had been excluded from all populations, probably belonging to other populations not sampled. In such a way, the set of results obtained, plus the biological characteristics of this species, and the distinct environmental characteristics among areas allow us to infer an existence of at least two F. brasiliensis stocks in Rio Grande do Norte coast.
Histórias infantis e matemática: a mobilização de recursos, a apropriação de conhecimentos e a receptividade de alunos de 4ª série do ensino fundamental
(Universidade Federal de São Carlos, 2008-07-28)
Souza, Ana Paula Gestoso de
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Oliveira, Rosa Maria Moraes Anunciato de
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https://lattes.cnpq.br/3064136997342775
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https://lattes.cnpq.br/2662760426985944
Considering a teaching/learning environment where literature and mathematics were connected, this research tried to investigate the ways by which the students of a fourth grade elementary school class acquired the school content, managed it and accepted the proposed methodology. In the theoretical reference, we discuss concepts and ideas such as: the perspectives of some authors on knowledge fragmentation and how it takes place in school; the means by which knowledge can be addressed in school; and the relationship of the students with such knowledge and with the teaching/learning context in which they are placed. We also discuss the impregnation of language with mathematics, the potential of reading, and the possibilities of developing a methodology that connects education, language, literature and mathematics. This research was developed in a fourth grade class of a public school in São Carlos (São Paulo State) according to a pedagogical sequence that articulated mathematics and children s literature the books chosen were The duck s lollipop and Sweet Fractions . The mathematical content developed was: fraction concept of part-whole, comparison and equivalence of fractions. The classes were recorded on video. Other information includes the number of students 33 and the fact that all of them participated in the pedagogical intervention, although only 13 had their learning processes and exercises analysed: the ones who had authorized us to do so. During the development of the pedagogical intervention, we could notice that many students were receptive to the work proposed i.e., the connection between literature and mathematics and acted as active subjects, taking part in the activities. Another aspect to point out is the importance of the use of manipulative materials for the students learning, because they allowed the children to come up with their own thoughts, and to produce and test hypotheses and strategies, getting involved in the process of understanding the material presented. By investigating the learning process of these students, we emphasize the educator s role as a mediator who, being aware of the previous knowledge of the students about certain subjects and understanding the strategies used by them to solve a situation, will be able to use some conditions and effective interventions in order to enable the students reasoning. Therefore, the students developed assumptions, strategies and interacted with the narratives, constructed mathematical notions, established a relationship of interiority with the knowledge, and the process itself involved the personal knowledge, life stories and experiences, i.e, the uniquenesses of each human subject who is part of the educational process and who creates himself/herself in daily school life, also creating the whole environment.
Avaliação química de solos tratados com vinhaça e cultivados com alfafa
(Universidade Federal de São Carlos, 2008-07-29)
Bianchi, Silmara Rossana
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Nogueira, Ana Rita de Araújo
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https://lattes.cnpq.br/7034773971317045
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https://lattes.cnpq.br/8503338877948315
It is fundamental the presence of nutrients in the soil to assure its good quality and performance. If the soil is not able to supply the adequate levels of nutrients that the plants need to survive, these nutrients have to be added in the form of salts or organic fertilizers. Vinasse, the main residue produced during alcoholic distillation (13 liters of vinasse to 1 liter of produced alcohol), is mainly constituted of organic matter, elevate amount of nitrate and potassium, and it has been used as a substitute of mineral fertilizers. In this work, the use of sensors that select chemical such as nitrate, ammonium, potassium and phosphate and its associated instrumentation was evaluated in the soil s ions monitoring throughout growing doses of vinasse in an alfalfa culture by using in situ analyses. The vinasse additions effects in the soil s chemical characteristics, in the alfalfa production, and in the ions leaching were evaluated. The use of vinasse to replacement mineral fertilizer in the alfalfa production was also evaluated. During the experiments, performed in a greenhouse, vinasse doses corresponding to 0, 300, 400, 600, and 750 m3 ha-1 were applied in the clay soil (Orthic Ferralsol), and 0, 150, 300, 450, and 600 m3 ha-1 were applied in the sandy soil (Ustoxix Quatzipamment). Doses of 150 mg kg-1 of K as KCl and K2SO4 were provided as mineral fertilizers. The results indicated the viability of the use of sensors installed in the probe in the ions soil monitoring, except of ammonium, which sensor suffers interference of the high amount of potassium present in the vinasse. Multiparametric analysis of the results allowed the view of the qualitative effects of the different treatments. Soils treated with vinasse presented an increase in the potassium, calcium, and magnesium amount, in the exchanged cations capacity, in the bases saturation and in the pH. The foliar amount of potassium harvest in the two kinds of soils also increased, and the vinasse fertilization produced more dry matter when compared with the mineral KCl and K2SO4 treatments. The amount of nitrate and ammonium presented in the leached solution were higher than the allowed by the Conama 357.