Browsing by Issue Date, starting with "2008-09-16"

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Caracterização elétrica de eletrólitos baseados em céria Nano e microcristalinos para pilhas a combustível
(Universidade Federal de São Carlos, 2008-09-16)
Lapa, Camila Maria
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Souza, Dulcina Maria Pinatti Ferreira de
;
https://lattes.cnpq.br/4100119317525940
;
https://lattes.cnpq.br/3459145799593883
Fuel cells are considered the most promising way for generating electrical energy in a near future. The economic fuel cells viability is directly related to the reduction of its operating temperature which is related to the properties of the electrolyte. In this work ceramic nanopowders of Ce0.8Y0.2O1.9 e Ce0.8Gd0.2O1.9 obtained by chemical synthesis were sintered through two-step sintering to obtain dense bodies with submicormetric grain size, in order to improve the grain boundary electrical conductivity of ceria-based electrolytes. Grain and grian boundary conductivities are dependent on grain size besides sintering schedule. The formation of secondary phases indicates that the improvement in grain boundary conductivity is related to the microdomains dynamics in microstructure. Ga2O3 addition was not effective in the densification of Ce0.8Y0.2O1.9 e Ce0.8Gd0.2O1.9 ceramics and it was deleterious to grain boundary conductivity, although it improved grain conductivity comparing to Ga2O3 free samples. An alternative to improve the electrical conductivity of ceria-based electrolytes is the formation of nanometric doped ceria amorphous carbonate composites. The composites were characterized and the components were set in different arrangements to evaluate the existence of interfacial effedt between the phases. The electrical characterization of these sets does not indicate the existence of this interfacial effect.
Síntese do feromônio sexual e respostas eletrofisiológicas frente ao óleo essencial de Psidium guajava de Tryrinteina arnobia
(Universidade Federal de São Carlos, 2008-09-16)
Neppe, Tiago
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Corrêa, Arlene Gonçalves
;
https://lattes.cnpq.br/7425467156776144
;
https://lattes.cnpq.br/7612655561022749
The study of semiochemicals involves the knowledge of different interaction levels between organisms and allows us to understand communication mechanisms and the action of specific compounds in the insect behavior. The eucalyptus-brown-looper, Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae) is considered an important pest in Brazil for native plants, as Psidium guajava, and exotic plants, as for example Eucalyptus species. This work describes the racemic synthesis of T. arnobia sex pheromone, 3,4-epoxy-6,9-heneicodiene, in 11 steps and 27% overall yield. The synthesized compound, tested by electroantennography (EAG) with male and female antennae at concentration of 100mg/mL, demonstrated identical bioactivity for both sex. We also obtained essential oils from leaves of wild white guava (P. guajava), by steam distillation, in order to investigate its electrophysiological action in T. arnobia. It was observed that the composition of young and old leaves of guava is different. Nevertheless, the EAG essential oil analyzes towards male and female antennae have shown that they are very bioactive. The synthetic pheromone and the kairomones isolated from the essential oil may allow us to understand the action of these substances in the insect behavior, through laboratory and field tests observation. Confirmed the substances attractive actions, their use in pest management will become very important.
Compartilhando um ambiente musical: processos educativos e relações afetivas entre pais e crianças de 8 a 24 meses
(Universidade Federal de São Carlos, 2008-09-17)
Raniro, Juliane
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Joly, Ilza Zenker Leme
;
https://lattes.cnpq.br/5569335876343450
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https://lattes.cnpq.br/4516334673723268
The research work here presented has as a theretical base, authors that believe that the social practices and the people's educational processes are developed and favored in the context of their interactions with the family, friends and the community enviromment, Considering that music can create opportunities for the people's development, including mental, corporal and social aspects, this research has for objective to study the affectionate relationships that happen in music classes offered for a group of children of eight months to two years and the adults that accompany them in the musical activities offered in a music education programm. Starting from the idea that to share musical activities it is a social practice between babies and parents, a more attentive glance for the aspects involved in this practice also brings information on the educational processes that happen in elapsing of the interactions. The data were collected and analyzed through a methodology of qualitative research, involving participant observation. Photographic registrations of classroom situations, impressions and two specialist researchers' reflections in musical education, aided in the reception of images and prominence of significant situations for the construction of the data. The diary of the researcher's field and the conversations accomplished between she and the observers were fundamental for the understanding of the affectionate relationships revealed in elapsing of the research. Considering tha the organization and analysis of the data was possible to highlight that the solidarity, the knowledge and respect with the other, the friendship and the construction of affectionate bows, such as the touch, the affection, the change of glances, they were stimulated and noticed in different activities of musical practice. The interface between the data and the literature allowed to reveal how musical activities shared between parents and their babies can be important for the strengthening of affectionate bows and for the people's development.
Narrativas de Thereza Santos: contribuições para a educação das relações étnico-raciais
(Universidade Federal de São Carlos, 2008-09-20)
Oliveira, Evaldo Ribeiro
;
Silva, Petronilha Beatriz Gonçalves e
;
https://lattes.cnpq.br/2447899367873195
This study, intitled Narratives of Thereza Saints - Contributions for the Education of the Ethnic-Racial Relations , have the objective to identify and to understand the pedagogical potentialities gifts in the narrative of Thereza Saints for the education of the ethnic-racial relations. Being thus, it is had following orienting question: Which pedagogical potentialities for the education of the ethnic-racial relations are gifts in the narrative of Thereza Saints? To understand the search field, it is had as theoretical references the education agreement, of education of the ethnic-racial relations, pedagogical potentiality and on narratives. The metodológicos ways have its bases in the fenomenológica position, being that it searched to understand the lived process. The identification and understanding of the pedagogical potentialities if had given from the principles pointed in Parecer CNE/CP 003/2004 establishing national curriculum guidelines for the education of education of the ethnic-racial relations and for the education of history and culture afro- Brazilian and African who are: conscience historical politics and of the diversity, reinforcement of identities and rights, educative actions of combat racism and to the discrimination. After to identify the pedagogical potentialities for the education of the ethnic-racial relations, was understood that they make possible: to fortify the ethnic-racial belonging, the ethnic identity, the conscience of the diversity of the ethnic-racial groups; to collaborate for the reinforcement of rights, the overcoming of the ethnic-racia inequalities, for the search for justice. It has possibility also learn-teach-to learn on African history, culture and values and afro-Brazilians. The study it pointed with respect to the importance of the guides, that is, the principles presented in Parecer CNE/CP 003/2004, to evaluate and to produce materials for the education of the ethnic-racial relations. It evidenced that to find pedagogical potentialities in education materials it is a tool for the education of the ethnicracial relations. It understood that Thereza Saints is a black intellectual and that in its narrative has elements that they contribute for the education of the ethnic-racial relations, for the construction of the black identity, for the education of history and culture afro- Brazilian and African and for the formation of professors.
Organizações e espaços da raça no oeste paulista: movimento negro e poder local em Rio Claro (dos anos 1930 aos anos 1960)
(Universidade Federal de São Carlos, 2008-09-26)
Pereira, Flávia Alessandra de Souza
;
Monsma, Karl Martin
;
https://lattes.cnpq.br/3083149924291027
In Organizações e Espaços da Raça no Oeste Paulista: Movimento Negro e Poder Local em Rio Claro (dos anos 1930 aos anos 1960) (Organizations and Spaces of Race in Western São Paulo State, Brazil: The Black Movement and Local Government in Rio Claro [from the 1930s to the 1960s] ) we try to comprehend the profile and shape of the black movement of the city of Rio Claro, and relations between this movement and the local government with regard to specifically racial demands. We focus on black spaces of sociability of Rio Claro, giving special attention to the identitary processes that shaped this sociability, and also to the demands that black actors addressed to the local government as part of the struggle for their own spaces of race in a white majority context, we emphasize, deeply marked both by open racism against blacks and by the impermeability of the local political system to blacks in general. It was in this context that the local black movement developed, over the course of decades, the basis for its collective mobilization for the long-desired house of its own a house that was materialized in its two social headquarters, finally built at the end of the 1960s. This research was supported by FAPESP (São Paulo State Research Fundation, Brazil, regular doctoral scholarship) and by CAPES (Coordination for the Improvement of Higher Education Personnel, Brazil, for foreign doctoral studies).
SEBRAE e empreendedorismo: origem e desenvolvimento
(Universidade Federal de São Carlos, 2008-09-26)
Melo, Natália Maximo e
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Grün, Roberto
;
https://lattes.cnpq.br/6028266827740491
;
https://lattes.cnpq.br/3166409854581684
Entrepreneurship is a term that has been present in the vocabulary of the Economy and the Administration and also in the common sense; however, rarely has been part of researches in social sciences. This dissertation describes the mains social actors who had contributed for the institutionalization of the entrepreneurship in the world. Moreover, it investigates one of the main actors that diffuse and support the entrepreneurship in Brazil: SEBRAE (Brazilian Service of Support to Micro and Small Companies). Describing it, we can identify how was introduced this subject (and term) in the programs of SEBRAE. Finally, the main of these programs, the Empretec, is investigated. It is co-coordinated by ONU and consists of a behavioral training which aim is to transform the behavior of individuals. Entrepreneurship seems in it not as academic concept with descriptive value, but as a prescriptive set of norms and values that guide and modify the perception of individuals.
Extrapolação espectral na restauração de imagens tridimensionais de microscopia ótica de fluorescência
(Universidade Federal de São Carlos, 2008-09-26)
Ponti Junior, Moacir Pereira
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Mascarenhas, Nelson Delfino d'Ávila
;
https://lattes.cnpq.br/0557976975338451
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https://lattes.cnpq.br/5041497500746910
The study of living cells, isolated or in tissues, in several applications, requires the use of microscopy techniques. The fluorescence microscopes are specially important for making possible images with enhancement of specific structures and detection of biological processes. However, microscopes, like other optical systems, corrupt images so that many details are lost after the passage of the image through their optical components. The conventional (wide-field) fluorescence microscopes degrade images mainly on the axial direction, limiting the amount of frequencies that passes through the system. As a result, there is an out-of-focus blur, making it difficult to use the images to obtain three-dimensional (3D) images by computational optical sectioning microscopy (COSM). The main contribution of this thesis is the development of computer-based methods that are able to restore acquired images, through spectrum extrapolation algorithms that restore a portion of the lost frequencies, even in noisy images. A non-linear algorithm was proposed, based on the Richardson-Lucy method, with space and frequency domain constraints as in the Gerchberg-Papoulis algorithm. this method defines an unified algorithm to restore and extrapolate images, focusing on the spatial finite support constraint. The proposed method showed improved extrapolation when compared to previously known methods. Besides, other algorithms were developed based on the proposed method. Each variation of the basic algorithm has distinct features to attenuate the noise, define adaptively the spatial constraint, and detect the image background region. The use of an adaptive constraint and the extraction of information directly from the images were shown to contribute to the recovery of lost frequencies. The results are promising, showing the potential of extrapolation in real conditions, improving the three-dimensional visualization of specimens in wide-field (non-confocal) microscopes, helping many important applications in biotechnology, such as the assessment of cell cultures.
Desafios do modo de vida da pesca artesanal em água doce num contexto socioambiental adverso : uma análise sociológica do caso do bairro rural do Tanquã, Piracicaba/SP
(Universidade Federal de São Carlos, 2008-09-29)
Venturato, Raquel Duarte
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Valêncio, Norma Felicidade Lopes da Silva
;
https://lattes.cnpq.br/7161606146208875
;
https://lattes.cnpq.br/2786495943179185
The intensification concerning the multiple uses of water in the Piracicaba River Basin has led to alterations in the aquatic ecosystem, affecting the fishery supplies with a deleterious influence and causing great limitations to the survival and social reproduction of traditional communities. The way of life within Tanquã community is centered on the artisan fishery, which implies on the fabrication of their own corporal techniques, ways of production, knowledge, beliefs and habits all characterized as traditional. The deterioration of the aquatic ecosystem acts as a factor of dissolution in this way of life. On one hand, by compromising and restricting the use of natural resources and on the other hand, by demanding the modernization of such techniques so that the artisan fishery can gain additional life span. There is reluctance within the Tanquã that appears as representations of their universe, in the oral memory, and the extra-economic sociability, providing a counterview to a full commitment to the market rationality. Between the desire to resist, affirming itself as a valid way of life, and the need to adjust to the dynamics of macro social environments, the Tanquã community lives the duality of a collective identity, sometimes strengthen, and sometimes threatened. As a case study, the objective of this article presents a brief description and a sociological analysis of the process, from a qualitative approach, in which the oral account and the direct observation are blend to characterize the structure and the dynamics of social production of the community.
Zoneamento ambiental do município de Querência - MT
(Universidade Federal de São Carlos, 2008-09-29)
Rossete, Amintas Nazareth
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Santos, José Eduardo dos
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https://lattes.cnpq.br/8533387365058570
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https://lattes.cnpq.br/1167022119179164
The sustainable use of the natural resources should be a basic premise to be integrated in environmental policies in order to avoid the growing natural ecosystems destruction. To assure a better appropriation of these resources is fundamental to apply the territorial arrangement landscape, with the formulation of environmental zonings. The municipality of Querência is located on Xingu River Basin, in the Northeast of Mato Grosso State, an Amazonian region knowledge as the arch of deforestation , in which has been registered the increase of clearing areas for farming and pasture in the last 20 years. The aim of this work is the environmental characterization and the elaboration of an environmental zoning of Querência municipality, starting from the definition and recognizing of different types of landscapes and land use, on the study area. The environmental inventory of the main environmental variables, that compose landscape, was made through field work and based on information processing in digital format of the thematic maps: planialtimetric, geology, geomorphology, pedology, agricultural suitability, vegetation and deforestation. Using geographical information systems - ArcGis 9.2 and SPRING 4.2 it was elaborated the land use and land cover maps obtained from CBERS II satellite (2006), as well as overlays operations that made possible the definition of landscape units, and resulted in the elaboration of the environmental zoning of Querência municipality. It was set up six zones: Preservation of Hydric Resources, Urban Use, Intensive Use, Forest Management, Protected Areas and Multiple Use.
Imobilização e estabilização de D-Hidantoinase para a produção de N-Carbamoil-D-Fenilglicina
(Universidade Federal de São Carlos, 2008-09-29)
Becaro, Aline Aparecida
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Giordano, Raquel de Lima Camargo
;
https://lattes.cnpq.br/9695542424889786
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https://lattes.cnpq.br/1283081812633332
Immobilization and stabilization of enzymes increases their potential for use in industrial scale. D-hydantoinases (dihidropirimidina amidrohidrolase EC 3.5.2.2) catalyze the hydrolysis of D-hydantoins, generating the corresponding Ncarbamoil- D-amino acid and are used in the production of D-amino acids, including Dphenylglycine and D-p-hydroxyphenylglycine.This work reports studies for immobilization and stabilization of D-hydantoinase from Vigna angularis (E.C. 3.5.2.2.). Different strategies of multipoint covalent attachment in organic supports as chitosan and agarose were used. Different protocols of immobilization were employed, being the adittion of ions during the reduction step with the NaBH4 important to protect enzyme catalytic site. The active and stabilized derivatives were used to catalyze the hydrolysis of D-phenylhydantoin. The temperature and pH enzyme profiles showed maximum enzyme activity at 60ºC and pH 10,0. The subunits of the enzyme present molecular mass aroundt 50kDa. The enzyme immobilized in glyoxyl-agarose in the presence of Zn2+ ions during the reduction step, with immobilization time of 24h, was the best derivative, being 89-fold more stable than the soluble enzyme. The analysis of amino acids showed that a 50% of lysines residue present in the enzymes was covalently linked in glyoxyl-agarose. The enzyme immobilized in epoxy-chitosan-alginate was 20-fold more stable than the soluble enzyme. All the tested immobilization protocols led to 100% of immobilization yield. Soluble enzyme and the best glyoxyl and chitosan enzyme derivatives were used to catalyze the hydrolysis of D- phenylhydantoin , and led to the production of 99% of NCarbamoil- D-Phenylglycine after 3, 9 and 15h of reaction respectively.
Trajetória de vida de intelectuais negros (as) : contribuição para a educação das relações étnico-raciais
(Universidade Federal de São Carlos, 2008-09-30)
Gomes, Ana Paula dos Santos
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Silva, Petronilha Beatriz Gonçalves e
;
https://lattes.cnpq.br/0269325539737205
The research presented here is inserted in the context of the deployment of Parecer CNE/CP/003/2004, which aims to attend the purposes indicated in CNE/CP 6/2002, which regulates the Law 10.639/2003. The objective is to contribute with the education of ethnical-racial relations making known and valued the life experiences and contributions of intelectual black scholars; experiences considered patrimony of the black comunity. The theorical references in this investigation bring discussions about intelectuals, black intelectuals, racial discrimination, valorization of African originated culture, patrimonial education, memory of black scholars, cultural patrimony. The matter of research that guides this study is: What educational processes, that are present in black people life trajectory, fashion them as black scholars? I search to know, through the report of situations lived by black scholars, research colaborators, how were they becoming intelectuals, how did they overcome obstacles and how they constituted themselves professionals in society without, however, lose sight of their ethnical-racial origin and their culture of African matrix. In the activity of registring the trajectory of black scholars life, I sought to observe the educational processes that were developed in their professional practices, of militance in contact to people surrounding them, be it in family, at work, in the community, among other environments. In life oral reports, collected in semi-structured interviews, I try to identify meanings in the experience of becoming a black scholar. The analysis of data was done under the form of a comprehensive description based on Fenomenology, in this process, I search for highlighting educational processes in which the research collaborators participated in different spaces in their lives: work, family, community. In these spaces, the black intelectuals built meanings and representations of their lives. They built their history and along with their target community, they rebuilt and rebuild the history of brazilian black people. Their life experiences reveal cultural, familiar and moral values that guide their lives. They point possible ways of racial discrimination superation and the conquest of fight and denounce spaces. They encourage the younger to keep with the black struggle aiming for equality and justice for the black people.
Interação plasmon-fônon LO em superredes semicondutoras
(Universidade Federal de São Carlos, 2008-10-07)
Rodrigues, Ariano de Giovanni
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Galzerani, José Cláudio
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https://lattes.cnpq.br/2448874919199274
This work presents a Raman investigation of the optical vibrations in highly doped In-GaAs/InP and GaAs/AlGaAs superlattices (SL s). The InGaAs/InP SL s grown with different periods were analyzed using polarized Raman techniques. No Raman selection rules were found in the long period InGaAs/InP SL s due to the structural defects in the bulk materials constituting the layers. With the decrease of the SL period the selection rules emerges and considerable blue shift of the longitudinal optical mode originated in the barriers were observed, as a manifestation of the coupled plasmon-LO phonon vibrations propagating along the growth axis. The observed effect can be attributed to the formation of the miniband electron energy structure. A quantitative analysis showed that the selection rules noticed in the longitudinal optical vibrations of the short period SL s occur due to the increasing of the coherence length of the coupled modes with respect to the coherence length of the optical phonon. The GaAs/AlGaAs SL s studied were growth with different disorder strengths. In weakly disordered SL s we also observed the coupling between the vertical plasmon and the longitudinal optical phonons of the barriers. The lineshape analysis of the sprectra measured in the strongly disordered SL s allowed us to obtain the plasmon damping constant, proving that in these samples the plasmon presents an overdamping behavior, that provokes the decoupling between the plasmon and the LO-phonon. For the first time we have shown aphysical system in which we can control the plasmon-LO phonon interaction, changing from a coupled regime to a decoupled one, by varying the disorder strength. Plotting both the coherence lengths of the AlAs-like coupled modes and the plasmon damping constants versus the disorder strengths we could draw some conclusion about the process of the transition from the coupled to uncoupled phase and to obtain the behavior of the plasmon relaxation as a function of the disorder.
As relações entre educação e trabalho nas trajetórias de alunos de uma escola técnica : uma análise a partir de Bourdieu
(Universidade Federal de São Carlos, 2008-10-07)
Stefanini, Deborah Maria
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Silva, Eduardo Pinto e
;
https://lattes.cnpq.br/3492708361349827
;
https://lattes.cnpq.br/7014309713393112
The research aimed at analyzing the conditioning factors that motivate technical high school students to seek this kind of education and at understanding the meaning of this schooling to them as well as their expectations and future aspirations as regard to education and labor. The study, based on Pierre Bourdieu and collaborators sociological perspective, was developed based on the educational and professional trajectories analysis of students at a technical high school in São Paulo state. The analysis was preceded by a bibliographical study about the historical context of the professional education in Brazil, which had as a backdrop its main target public throughout the years, as well as the considerations concerning professionalization in the context of productive restructuring. The propensity to the technical education was analyzed based on the students social status and their internalized dispositions, designated habitus. It was observed that the inclination to the technical education is supported on a disposition that emphasizes the work instead of long studies. That trend establishes a contradiction lived by the families between the ideal the school longevity and the necessary the work. That internalized and durable disposition tends to determine the studies extension which, according to them, must be associated to the professional insertion. However, the education is assimilated as primordial for social mobility and the students internalize the idea that is necessary to continue studying. In this direction, the technical education, currently organized as a quickly course, is considered as a possibility for obtaining the studies extension, since other ways for that are uncertain or financially unfeasible. In most cases analyzed, the technical education has an instrumental meaning, as a way to aid in the self-subsistence for a future maintenance in the higher education, as a way to help to get better professions. On both cases, this education is assimilated as a form to enhance competition and not necessarily the obtention of work in the technical formation area.
Educação entre grades : um estudo sobre a educação penitenciária no Amapá
(Universidade Federal de São Carlos, 2008-10-07)
Abreu, Almiro Alves de
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Bezerra Neto, Luiz
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https://lattes.cnpq.br/4809080593333472
;
https://lattes.cnpq.br/7377134509470946
Le présent travail intitulé Éducation entre grilles : un étude sur l Éducation pénitencier dans l Amapá amene à discussion la compréhension du phénomene prisonnier versus éducation versus réssocialisation, de façon à subsidier chercheurs et Administration publique en général. L objectif basique constitue en comprendre et analiser l éducation ministrée dans l école du complexe pénitencier du l Amapá, qui est sous l administration de la Secrétariat du l état de l éducation.. Pour la sustentation théorique on a cherché discuter les lois que prévent les garanties des droits des prisonniers à l éducation, ainsi que, les plus actualisés les auteurs nacionaux et étrangèrs qui sont en train de produire et publiqué sur le thème. Comme abordage méthodologique, on a utilisé la Méthode Historique-descriptif des sciences sociaux et la statistique, pour qu on pusse tabuler les donnés et à partir de ce moment, procéder à une analyse interpretatif-qualitative, ayant par référence axes thématiques centrales. Comme thécnique de recherche on a utilisé questionnaire et interview semi-structurée. On part de la prémisse de que l éducation offris dans IAPEN n a pas accomplie avec son papier ressocialisateur, a été possible répondre les demandes : Comment se donne la rélation professeur et élève, la méthodologie, et le contenu travaillé dans E.E.S.J ? Quel est la formation des profissionnels qui directement travaillent avec l élève-prisonnier ? Basé dans ces questionnements a été possible formuler l hypothèse de que l éducation aide la reintegration du l élève-prisonnier, qui a été confirmé par les donnés empiriques, répresentés par les résultats suivants : Pour l élève-prisonnier l éducation repésente seulement une façon de sortir de la cellule et pouvoir donner une promenade par les autres bâtiments du IAPEN, ainsi qu un mecanisme de communication, car entendre que c est dificille qu il aura chance de obtenir un emploi ici, au dehors, une fois que, ce qu on apprend, n aide pas lui à s intégrer dans la societé en général, soit par le travail, ou par l éducation. En rélation aux professeurs, ils croient constituer un chaînon entre la culture en général et la culture dans la prison. C est important mentionner que par plus qu on fasse des efforts pour offrir au élève-prisonnier une éducation de qualité, les conditions de travail ne répondre pas à ses besoins, ayant beaucoup des fois que improviser dans la salle de classe, car l école-champ, par fois, n a pas même le craie, n a pas aussi des moyens didáctique-technologique. En référence aux membres qui font partie de la gestion du complexe a étè possible percevoir qu ils font des efforts, la mesure du possible, pour faire l école fonctionner pour pouvoir atteindre ses objectifs, ils travaillent pour structurer l école pour être le référentiel de éducation prisional dans l État.
Estudo das transições de fase em cerâmicas ferroelétricas de PZT e PLZT através de espectroscopia mecânica
(Universidade Federal de São Carlos, 2008-10-08)
Silva Junior, Paulo Sergio da
;
Florêncio, Odila
;
https://lattes.cnpq.br/9659972316642270
Lead titanate zirconate (PZT) and lanthanum-modified lead titanate zirconate (PLZT) ferroelectric ceramics have been great scientific and technologic interest, due to the possibility of your physics properties can be optimized and adequated for specific technologic applications. Scientifically, the anelastic characterization of the phase transitions have a fundamental importance to understand the phenomenology and behavior of the intrinsic properties. In this work, the phase transition exhibit by PZT and PLZT were studied, for Zr/Ti ratios of 40/60 and 65/35 for PZT, and Zr/Ti ratio 65/35 for PLZT, with lanthanum concentration between 5 mol-% and 9 mol-%, by mechanical spectroscopy technique. The nelastic spectra as a function of temperature and frequency were performed in acoustic elastometer equipment, operating in a temperature range of 300 K and 770 K, with frequencies in a kHz bandwidth, for heating rate of 1 K/min, under a pressure higher than 10−5 Torr. Dielectric chracterizations of PZT 40/60 and PZT 65/35 ceramics showed the normal ferroelectric behavior of ferroelectric-paraelectric phase transition. Dielectric analysis of PLZT ceramics showed the change of the normal ferroelectric behavior to relaxor-like and diffusive behaviors for the ferroelectric-paraelectric phase transition with the increase of the lanthanum amount. Anelastic spectra of PZT 40/60 showed the presence of two anomalies associated with relaxation mechanism of interaction between 900 domain walls with Zr and Ti vacancies, and the ferroelectric-paraelectric phase transition, respectively. For PZT 65/35 the anelastic results appoint the presence of one single anomaly associated to ferroectric-paraelectric phase transition. PLZT 5/65/35 and PLZT 8/65/35 showed in anelastic spectra two frequency-independent anomalies, associated to ferro-ferroelectric and ferroelectric-paraelectric phases transitions. In anelastic spectra of PLZT 9/65/35 was observed only one single anomaly associated to ferroelectric-paraelectric phase transition. The anelastic and dielectric spectra analysis showed the same behavior of temperature of ferroelectric-paraelectric phase transition with the change of lanthanum amount, where were observed the decrease of temperature of ferroelectric-paraelectric phase transition as a function of the increase of lanthanum amount. The effect of symmetry exchange in PZT ceramics not showed the change in electromechanical coupling type, being this linear coupling type between strain and polarization. The increase of lanthanum amount in PLZT ceramics showed a continuum change of electromechanical coupling type, starting with a linear coupling between strain and polarization (PZT 65/35) and changing to linear coupling in strain but quadratic in polarization (PLZT 8/65/35 and PLZT 9/65/35).
Alterações de longo prazo na ingestão de sódio : aspectos neuroendócrinos, genômicos e comparativos
(Universidade Federal de São Carlos, 2008-10-10)
Pereira-Derderian, Daniela de Toledo Borba
;
Luca Júnior, Laurival Antonio de
;
https://lattes.cnpq.br/4542655683955902
Sodium intake occurs either as a need-free or a need-induced behavior, which is enhanced by repeated episodes of treatments leading to extracellular dehydration or increased levels in natriorexigenic hormones. This enhancement is likely an adaptation to repeated episodic sodium loss mediated by the long-term effects of hormones on brain circuits subserving sodium appetite. The objective of the present thesis was to investigate three aspects of long-term alterations in sodium intake associated to angiotensin (ANG) II: 1) neuroendocrine: the effect of repeated episodes of FURO/CAP on need-induced and need-free sodium intake, 2) genomic: associate hypothalamic renin-angiotensin system mRNA alterations with sodium intake enhancement induced by repeated episodes of water deprivation followed by partial rehydration with water (WDPR), and 3) comparative: sodium appetite in SHR submitted to a single WDPR. Both protocols, WDPR and FURO/CAP, were effective methodologies to enhance sodium intake, not related to systemic changes, suggesting that its mechanisms are due to neural plasticity and salt addiction. Repeated blockade of Agtr1 receptors by losartan inhibited or abolished the enhancement in the need-free sodium intake produced by a history of FURO/CAP. This result suggests that encephalic ANG II may play a role in the sensitization of spontaneous sodium intake, and perhaps it does not occur in the hypothalamus because it was not correlated to any hypothalamic RAS mRNA alteration in the WDPR protocol. However, hydrated animals with a history of WDPR increased the hypothalamic mRNA encoding of ANG II receptor type-1a (Agtr1a) by 76%. The enhancement in the need-induced sodium intake in the WDPR was related to increased hypothalamic mRNA encoding of angiotensinogen, aminopeptidase N, X Agtr1-associated protein, and ANG receptor like-1 or apelin receptor by 43%, 60%, 36%, and 159% respectively. Thus, the enhancement in the sodium appetite in WDPR was associated with alterations in the hypothalamic gene expression related to RAS. Thus, hypothalamic ANG II and apelin may play a role in the long-term changes of need-induced sodium intake. Moreover, the increased cellular activity that occurred in the subfornical organ, pre-locus coeruleus, and caudal nucleus of the solitary tract is associated with a stronger sodium appetite shown by SHR. These results suggest that increased cellular activity in these areas is correlated with the avid sodium appetite shown by SHR in response to water deprivation. The results suggest that repeated activation of encephalic ANG II receptors, perhaps in different areas, is able to enhance both forms of sodium intake and reinforce encephalic ANG II as a peptide that mediates long-term effects on behavior.
Desempenho eletroquímico de compósitos de nanotubos de carbono como anodos para baterias de íon-lítio
(Universidade Federal de São Carlos, 2008-10-10)
Bento, Fábio Ricardo
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Mascaro, Lucia Helena
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https://lattes.cnpq.br/9130022476352844
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https://lattes.cnpq.br/2523005531689304
In this work CNTs composite for use as Li-ion anode materials had been investigated. The electrochemical properties of the electrodes were measured by galvanostatic charge-discharge testes, cyclic voltammetric analysis and electrochemical impedance spectroscopy. The first materials was discussed were the NiO:MWNTs composite. Previously, NiO powders were prepared via the spray pyrolysis technique and, the NiO:MWNTs composite was prepared by dispersion simultaneously of MWNTs and NiO powders using ultrasonicator. The electrochemical properties of NiO:MWNTs composite were investigated to determine their suitability as anode materials for lithium-ion batteries. The NiO:MWNTs composite electrodes exhibited better reversibility and higher capacities than NiO and MWNTs electrodes. The reasons for improved electrochemical performance of the composite electrodes are discussed. Another composite had been investigated was C-SnO2-SWNTs. The C-SnO2-SWNTs composite powder was prepared by mechanical ball milling and [C-SnO2]- dSWNTs was synthesized by dispersion SWNTs via ultrasonication into a premilled C-SnO2 composite mixture. It was found that the cyclic performance of the both composite materials was improved when they was compared to CSnO2. Free-standing SWNT paper electrodes have been synthesized by a simple filtration. With addition of C-SnO2 composite powder was prepared by mechanical milling, the specific capacity of the free-standing ([CSnO2] 0.5SWNTs0.5) paper electrode were greatly enhanced, so that they retained a capacity of 310 mAh g-1 beyond 30 cycles. On the other hand, the procedures for SWNTs electrode preparation were simplified, so the cost of the manufacturing could be reduced. The specific capacities at 20th cycle decrease in the order: [C-SnO2]-dSWNTs > [C-SnO2]0.5SWNTs0.5 > C-SnO2-SWNTs > NiO:MWNTs (70:30) > C-SnO2 > NiO > MWNTs.
O efeito do alongamento intermitente e da eletroestimulação na expressão gênica, na atividade de metaloproteases e na morfologia do músculo esquelético em ratos
(Universidade Federal de São Carlos, 2008-10-10)
Messa, Sabrina Peviani
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Salvini, Tânia de Fátima
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https://lattes.cnpq.br/3105529494736011
Metabólitos secundários de Streptomyces clavuligerus ATCC 27064 e fungos endofíticos filamentosos
(Universidade Federal de São Carlos, 2008-10-11)
Benavides, Diana Jimena López
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Rodrigues Filho, Edson
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https://lattes.cnpq.br/3667941735597178
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https://lattes.cnpq.br/3173023019682551
This work describes the investigation of part of the secondary metabolism of actinomicete Streptomyces clavuligerus and endophytic filamentous fungus Penicillium sp isolated from Murraya paniculata; Penicillium brasilianum and Aspergillus aculeatus isolated from Melia azedarach and Penicillium griseoroseum isolated from the grains of Coffea arabica. Preliminary tests were realized to define the best composition of medium culture and the best condition of cultivation Streptomyces clavuligerus. On the other hand, the endophytic fungus were cultivated in rice and Czapec´k (medium liquid). The anthranilic acid and the 7-hydroxy-2- methyl-chromone were identified from the extracts of S. clavuligerus by spectroscopic methods 1D e 2D NMR and mass spectrometry. Methodologies of analysis for detection of β-lactam antibiotics were developed by liquid chromatography combined with mass spectrometry. The identification was based on studies of standard compounds and comparison with literature data. These methodologies were efficient in the analysis of this type of substances and they allowed the detection and identification of β-lactam antibiotics such as the penicillin N, the cephamycin C, deacetoxy-cephalosporin C and the clavulanic acid in small amounts in S. clavuligerus the extracts. In the endophytic fungus extracts were possible to identify the 6-aminopenicillanic acid, precursor of the penicillin G and metabolites no β-lactams as nucleotides thymine and adenine.
Detecção por PCR da presença da bactéria bartonella em humanos com cardiopatias
(Universidade Federal de São Carlos, 2008-10-12)
Corrêa, Fabrício Gonçalves
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Araújo, Heloísa Sobreiro Selistre de
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https://lattes.cnpq.br/4065824911933203
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https://lattes.cnpq.br/8202689960962492
Many studies have demonstrated that infection by Bartonella vinsonni subspecies berkhoffii may cause cardiac arrhythmia, myocarditis and infectious endocarditis in humans. There is strong evidence that Bartonella vinsonni is an important cardiac pathogen in both humans and dogs The Bartonella sp has been associated with several human diseases, being responsible for a number of zoonoses. The aim of this work was to identify and correlate the Bartonella vinsonni subsp. berkhoffii with the cardiac disease by using specific oligonucleotides as Bh16SF and Bh16SR, which amplify a 185-bp fragment of 16S rRNA. The PCR technique was used for detection of this bacterium in human leukocytes. The amplification products were analyzed in 1.5% agarose gel in order to confirm the 185-bp fragment, which in turn indicates the presence of the bacterium. Thirty eight (39%) out of the 96 humans with cardiopathies as well as 16 (15%) out of the 104 humans from the control group showed positive PCR amplification for Bartonella vinsonni subsp. berkhoffii, thus suggesting a positive correlation of this subspecies with the cardiopathies. Sequencing of the amplified product confirmed the presence of Bartonella vinsonni subspecies berkhoffii.