Repository logo
Communities & Collections
Entire repository
About
English
العربية
বাংলা
Català
Čeština
Deutsch
Ελληνικά
Español
فارسی
Suomi
Français
Gàidhlig
ગુજરાતી
हिंदी
Magyar
Italiano
Қазақ
Latviešu
മലയാളം
मराठी
Nederlands
ଓଡିଆ
Polski
Português
Português do Brasil
Русский
Srpski (lat)
Српски
Svenska
తెలుగు
தமிழ்
Türkçe
Yкраї́нська
Tiếng Việt
繁体中文
Have you forgotten your password?
  1. Home
  2. Browse by Date

Browsing by Issue Date, starting with "2010-05-21"

Filter results by year or month
Now showing 1 - 20 of 20223
  • Results Per Page
  • Sort Options
  • Loading...
    Thumbnail Image
    Item type:Item,
    Tutoria para alunos com baixo aproveitamento acadêmico e o desenvolvimento de cognições e estratégias de leitura e escrita
    (Universidade Federal de São Carlos, 2010-05-21)
    Buzetti, Miryan Cristina
    ;
    Rose, Tânia Maria Santana de
    ;
    https://lattes.cnpq.br/3077411745176722
    Studies have identified a set of teaching conditions associated with tutoring effectiveness focused in book reading for preventing the writing and reading failuse as a form of supporting teaching to regular education. In this study was sought to 1) to verify the connection between the education condition offered in a tutoring focused in the book reading and education conditions associated to reading skills and writing improvements; 2)evaluate the tutoring effects on reading and writing skills on students whit low achievement in early literacy from data on performance throughout the tutoring sessions and the performance presented on evaluated tasks by specific assessment tools applied at the beginning, intermediate and final stage of the intervention; 3) describing the progress of reading strategies used by students. The participants were four students in the same second grade class of public elementary school, they were selected due to the low reading and writing achievements. During 17 weeks in a semester, the students attended 3 tutoring weekly sessions around 30 minutes each. In each session the interaction between the tutor and the student was directed in order to make possible for the students to have the commitment in a book presentation which isn´t still familiar made by the tutor, independent reading made by the student of a familiar book and a non familiar one, the involvement in activities for the recognition of letters, syllables and words, speaking and writing sentences and stories, decomposition and recomposition of sentences and stories. The results allow us to conclude the teaching conditions offered responded satisfactorily to the guidelines predict by the experts and professionals who work with tutoring focused in reading. Is was verified the tutor had a previous training to conduct the reading and writing activities in the tutoring sessions. Performing as a supporter in a students learning, encourage the student´s strengths in terms of reading and writing for each student, and systematically made adjustments that me the specific difficulties of each student, helped the students to read accurately through the use of suitable books to the level of difficulty of each student. Regarding to the effects on the students, the results indicate a substantial increase in the percentage correct reading of words and texts, writing dictated words and in the use of appropriate reading strategies such as self-correction and search for meaning. The teacher´s report about the students achievement in the classroom indicate a recognition of the reading an writing students improvement due to the support provide by tutoring.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Diversidade genética e filogeografia das espécies Hoplias malabaricus (Bloch, 1794) e Prochilodus lacustris Steindachner, 1907 no Nordeste do Brasil
    (Universidade Federal de São Carlos, 2010-05-21)
    Piorski, Nivaldo Magalhães
    ;
    Galetti Júnior, Pedro Manoel
    ;
    https://lattes.cnpq.br/7220575466585169
    The State of Maranhão is considered as a transitional area between northeastern semiarid and amazonian rainforest. Various perennial rivers such as the rivers Parnaíba, Itapecuru, Mearim, Pindaré and Gurupi are found in Maranhão. Distribution patterns analysis indicated the region as an endemism area for Neotropical freshwater fishes. However, only few studies have been performed in the region. Therefore the relationships between the hidrographic set and the respective neighbour areas are not fully comprehended. One complication is the insufficient cientific knowledge about the endemism level in the region due to insufficient establishment of taxonomic bounds for several species in the area. This study examines the hypothesis that freshwater fishes from Maranhão rivers are valid taxonomic unities, and whether its hydrographic set can be considered as an endemism area for Neotropical fishes. The study is focused on the analsis of genetic differentiation of Hoplias malabaricus and Prochilodus lacustris. The geographic variation of H. malabaricus was studied using sequences of the DNAmt control region as well by geometric morphometrics. Besides the mitochondrial marker, the variation analyses of P. lacustris employed sequences of the S7 intron 1. Both species exhibited high genetic variability which may be related to its own ecological features. The genetic diversity of H. malabaricus, a sedentary species, is influenced by drainage architeture. On the other hand, the migratory behavior of P. lacustris and the results obtained had suggested that the variability found was influenced by historical factors. Because the most resolution of the P. lacustris data, the molecular clock hypothesis was tested and divergence times between populations sampled were estimated. These estimates matching with geological informations enabled us to identify several putative events that may play an important role in differentiation of the maranhense ichthyofauna. Under the taxonomic point of view, the hypothesis that H. malabaricus is a species complex was reinforced and the analyses suggested that putative criptic species occur in the region. The P. lacustris specimens constitute a taxonomic unit, but did not support the hypothesis that the species is endemic for the Parnaíba and Mearim rivers. Considering these results, we suggest that the most closely indication of endemism areas could be the ecoregions established by Secretaria de Recursos Hídricos from Ministério do Meio Ambiente.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Influência da nanoargila no envelhecimento higrotérmico de compósitos de polipropileno / PP maleado / fibra de vidro
    (Universidade Federal de São Carlos, 2010-05-21)
    Motezuki, Joice Erica
    ;
    Sousa, José Alexandrino de
    ;
    https://lattes.cnpq.br/7737833809468759
    ;
    https://lattes.cnpq.br/0763843840252541
    In short glass fiber (GF) reinforced polypropylene (PP) composites, despite of the chemically inert and non-polar nature of the matrix, the fiber-matrix interfacial integrity may be compromised in a hygrothermal active environment by the addition of maleic anhydride (MAH) molecules of the interfacial compatibilizer (PP-g-MAH). The use of organophilic nanoclay particles (O-MMT, Cloisite 20A) could contribute to minimize this hygrothermal deterioration, due to its moisture barrier properties. So, the main goal of this study was to analyze the influence of O-MMT on the long-term mechanical performance of PP/PP-g-MAH/GF composites under hygrothermal ageing. Several PP composite formulations with constant GF content (40wt%) and varying concentrations of nanoclay (0.5; 1; 2; and 5wt%) were compounded in a corotating twin-screw extruder. The degree of nanoclay particles intercalation/exfoliation was characterized by X-ray diffraction (WAXD) and SEM/TEM microscopy analysis. Short-term mechanical characterization was carried out through standard tensile and Izod impact tests on injection moulded specimen. From this results, certain specimen were subjected to hygrothermal ageing in hot water at 80 ºC for 240/480/720 hours and the evolution of the hygrothermal deterioration was monitored by tensile tests. The increasing O-MMT content in unaged PP/PP-g-MAH/40%GF composites had an unexpected negative influence on short-term mechanical properties. Mechanical damping data indicated higher Tan  values for the ternary composite (PP/PP-g-MAH/40%GF/2%O-MMT), in comparison to the binary composite (PP/PP-g-MAH/40%FV), demonstrating deleterious effect of O-MMT on the fiber-polymer interfacial adhesion. SEM microscopy analysis of cryofractured surfaces were decisive for visual elucidation of the erosive action of O-MMT particles on the GF sizing treatment. Consequently, the relative tensile strength (TS) of the hygrothermally aged composite, with respect to that of the unaged composite (TSenv./TSn-env.), indicated that the addition of nanoclay in the ternary composite contributed to a higher deterioration of the long-term mechanical performance of GF-reinforced PP composites.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Confinamento de partículas quânticas a curvas do espaço
    (Universidade Federal de São Carlos, 2010-05-24)
    Verri, Alessandra Aparecida
    ;
    Oliveira, César Rogério de
    ;
    https://lattes.cnpq.br/5485204156806697
    ;
    https://lattes.cnpq.br/8794549732815622
    In this work we study dimensional reductions in some quantum systems; such reductions occur due to confinement of the particle from a tube in space to a curve. Our main goal is to find the effective hamiltonian operator that describes the motion of the particle after confinement. We consider three particular situations. (1) In the first situation, we study an infinitely long tube generated by a curve with non-trivial torsion and curvature. Here the tube cross sections always have the same diameter. (2) We also study tubes in space deformed in a specific way, i.e., the diameter of the cross sections have a unique global maximum. Such tubes also have non-trivial torsion and curvature. (3) Finally, we analyze the question of which self-adjoint extension of the one-dimensional hydrogen atom would be physically relevant. We consider such atom in a three-dimensional tube and take the limit as the tube converges to the x axis, and it is shown that the Dirichlet (at the origin) extension is always obtained after such confinement.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Avaliação do papel do pulso de inundação sobre a riqueza e biodiversidade de peixes em ambiente inundável, no sistema de baías Caiçara, porção norte do Pantanal Matogrossense, alto Paraguai
    (Universidade Federal de São Carlos, 2010-05-24)
    Muniz, Claumir Cesar
    ;
    Peret, Alberto Carvalho
    ;
    https://lattes.cnpq.br/0995579236780271
    ;
    https://lattes.cnpq.br/2202899559144774
    The present study was aimed to assess the role of the flood pulse related to the composition of the ichthyofauna of the Caiçara Basin System (Upper Baía Caiçara/UBC e Lower Baía Caiçara/LBC) in a pantanal environment, in Cáceres, Mato Grosso. 90,041 specimens were collected from September 2005 to September 2007, distributed in two classes, 8 orders, 32 families and 171 species, with 145 of them occurring in both environments. Characiforms, Siluriforms and Gymnotiforms were the most representative orders accounting for more than 90% of all the species obtained in the sampled environments. The UBC, with 155 collected species, considering the two sampled cycles, obtained 68 and 81 constant species, accounting for 50 and 56% of the total species in this bay. In the LBC, with 161 sampled species, the constant species were most significant, with respectively 43 and 56% per cycle and 54 species for the entire sampling period. Odontostilbe pequira, Serrapinnus calliurus and Moenkhausia dichroura were abundant in all the periods. M. dichroura was the most abundant species in practically all the periods and environments. Cyphocharax gillii and Hypoptopoma inexspectatum (detritivores) were abundant in the ebb tide and dry periods. Acestrorhynchus pantaneiro and Roeboides prognathus were the most abundant piscivores in the ebb tide period. Hemiodus orthonops was abundant in the flood and high tide periods. Among the invertivores/insectivores, M. dichroura and O. pequira were abundant in all the seasonal periods. Concomitantly to the fish collection, data from the limnological variables in the two sampled environments were also obtained, which showed significant differences between the seasonal periods. In the dry periods, the UBC remained totally disconnected from the Paraguay River, and the BCI obtained a smaller water amount from the main channel. In the flood period the connectivity between the UBC and the Paraguay River was reestablished. The concentration of dissolved oxygen varied from 0.67 to 5.94 mg/l in BCS and 0.64 and 5.87 mg/l in the LBC. The highest water temperatures were observed during the flood period (31.35 °C) and the lowest temperature during the dry period (22.33°C). Concerning electrical conductivity, the highest values were observed in the flood period (84.19 μS.cm-1). The lowest values were obtained in the ebb tide period (23.30 μS.cm-1). It obtained the lowest pH values (5.66) in the high tide period, and the highest pH values (7.50) in the dry period. Characiforms and Siluriforms were the orders that showed the best adaptation to the variations caused by the flood pulse of this system and the limnological attributes (dissolved oxygen, pH, electrical conductivity in water, pH, water transparency and depth) are decisive in the arrangement of the ichthyofauna, but their action is not isolated. On the contrary, they are interdependent together with the river-basin connectivity.
  • Loading...
    Thumbnail Image
    Item type:Item,
    O fitoplâncton como instrumento de biomonitoramento da qualidade da água do Reservatório de Cachoeira Dourada - Rio Paranaíba - GO/MG
    (Universidade Federal de São Carlos, 2010-05-24)
    Oliveira, Márcia Teixeira de
    ;
    Peret, Alberto Carvalho
    ;
    https://lattes.cnpq.br/0995579236780271
    ;
    https://lattes.cnpq.br/7107251497009712
    The phytoplankton community is one of the communities recommended as a tool for evaluations of water quality. The relevance of ecological and sanitary studies of phytoplankton to public health is due to the fact that they attest to water quality and allow waters to be monitored for multiple uses, especially those linked directly to human health. The phytoplankton community of the Cachoeira Dourada reservoir was characterized in the months of December 2006, May 2007 and November 2007 at five sampling points, four of them in the reservoir and one downstream. The phytoplankton sampling, which was based on the principles of the AquaRAP, aimed to evaluate water quality using indices based on physical, chemical and biological characteristics, with emphasis on the phytoplankton community. The results revealed that the phytoplankton was dominated by cyanobacteria in the three sampling periods. Cyanobacteria exhibited higher significance in terms of richness and greater density than the other classes of phytoplankton. Potentially toxic species were represented by Anabaena sp. and Microcystis sp., with higher occurrence during the dry season, albeit in low densities. There was no record of blooming and the analyzed densities lay within the limit established by CONAMA (National Environmental Agency). The reservoir was classified as oligotrophic, based on its phytoplankton diversity, equitability, richness and density. This classification was confirmed by an analysis of the reservoir s physical and chemical variables and by several other indices applied with or without the use of the phytoplankton community. Among the various indices employed, Nygaard s index was the only one considered inefficient in evaluating the trophic degree of the reservoir, because it neglects species density. Phytoflagellates proved to be a good indicator of environments with low transparency (CCA). The main interferents in the reservoir s water quality were found to depend on factors of climate, the dam s operation, and anthropic activities in adjacent areas and in the drainage basin, which were dynamically reflected in the composition and structure of the phytoplankton community in the different periods under study. It is also important to note that the brief residence time of the water is probably the preponderant factor for this oligotrophic state of the reservoir.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Análise da superfície de porcelanatos polidos por meio de microscopia de força atômica
    (Universidade Federal de São Carlos, 2010-05-24)
    Fernandes, Mérilin Cristina dos Santos
    ;
    Paulin Filho, Pedro Iris
    ;
    https://lattes.cnpq.br/9542027656569433
    ;
    https://lattes.cnpq.br/2740250822457796
    The porcelain stoneware tile is a ceramic product that has presented a great increase on production, since it had excellent technical properties and raised aesthetic performance. To improve its aesthetic characteristics, it is submitted to a polishing process that influences a lot of interested properties of the products, due mainly to changes observed on the superficial roughness. In this way, the roughness was investigated throughout the superficial polishing process of the glazed and unglazed (technical) porcelain stoneware tile and it was correlated with the gloss. For this, the Atomic Force Microscope (AFM) was used, being ideal to measure the roughness in nanometer scale and to visualize the nanotexture of many types of surface materials. The specular part of the gloss was measured through the equipment known as glossmeter. The results achieved shown that the technical porcelain stoneware tile in the first stage is more rough than the glazed. On the technical porcelain stoneware tile the roughness reduction was more accented between the grit 80 and 1000 stages, and the gloss was practically double between the first and the last (POLIDO) stages. The surface covering with the polymeric resin reduced significantly the product gloss, without it causes brusque alterations in superficial roughness. On the glazed porcelain stoneware tile the roughness reduction and the gloss increased occurred mainly between the grit 600 and 1800 stages. Between the grit 1800 and 8000 stages had not observed great changes on the roughness or gloss, showing that the polishing becomes unnecessary from the grit 1800. In general way, the gloss reduction occurred more visibly in stages of polishing with abrasives of larger grains, while the abrasives of smaller grains had given the final gloss, intervene poorly in roughness. The results interpretation had supplied subsidies to a better understanding and control of the process responsible for the final characteristics between the glazed and technical products, and the differences between these typologies.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Novas propostas em filtragem de projeções tomográficas sob ruído Poisson
    (Universidade Federal de São Carlos, 2010-05-24)
    Ribeiro, Eduardo da Silva
    ;
    Mascarenhas, Nelson Delfino d'Ávila
    ;
    https://lattes.cnpq.br/0557976975338451
    ;
    https://lattes.cnpq.br/5036975831625237
    In this dissertation we present techniques for filtering of tomographic projections with Poisson noise. For the filtering of the tomogram projections we use variations of three filtering techniques: Bayesian estimation, Wiener filtering and thresholding in Wavelet domain. We used ten MAP estimators, each estimator with a diferent probability density as prior information. An adaptive windowing was used to calculate the local estimates. A hypothesis test was used to select the best probability density to each projection. We used the Pointwise Wiener filter and FIR Wiener Filter, in both cases we used a adaptive scheme for the filtering. For thresholding in wavelet domain, we tested the performance of four families basis of wavelet functions and four techniques for obtaining thresholds. The experiments were done with the phantom of Shepp and Logan and five set of projections of phantoms captured by a CT scanner developed by CNPDIA-EMBRAPA. The image reconstruction was made with the parallel POCS algorithm. The evaluation of the filtering was made after reconstruction with the following criteria for measurement of error: ISNR, PSNR, SSIM and IDIV.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Governanças híbridas no comércio justo citrícola entre o Brasil e a Europa: arranjos institucionais complementares aos contratos
    (Universidade Federal de São Carlos, 2010-05-25)
    Bouroullec, Melise Dantas Machado
    ;
    Paulillo, Luiz Fernando de Oriani e
    ;
    https://lattes.cnpq.br/9919942357089937
    ;
    https://lattes.cnpq.br/2303972253901596
    Focusing on hierarchy as an alternative to market, the New Institutional Economics (NIE) initially focused narrowly on the intermediary organizations. However, this situation started to change when Williamson (1985) stated that such intermediary transactions are the most common ones and denominated them hybrid governance in 1991. The studies carried out in the 80s and 90s enabled, among other factors, the distinction between hybrid governance and hierarchy resulting in an arousing interest in the development of contracts and the different coordination mechanisms in the field of NIE. More recently, some authors have highlighted the importance of studies on hybrid governance in the agricultural sector. Thus, the objective of this thesis is to indicate the existence of hybrid governance forms that complement the contract in transactions of supplying fair trade orange juice to the European market, as well as to point out the determining factors of this kind of governance. Therefore, the institutional environment of the agro-industrial fair trade is analyse, still poorly investigated in scientific studies in Brazil, and hybrid governance, considering the contributions of Ménard (1997, 2004) to the development of the concepts of NIE, were analyzed. Secondary data were considered and a field research was carried out both in Brazil and in Europe. Interviews were conducted with organizations of citrus farmers that are already inserted in the international citrus fruit fair trade, with export and import orange juice companies, and with some key agents. The analyses showed that orange juice supply transactions of the fair trade are administered by complex mechanisms that are more complex than contracts. Due to investments on human and brand name asset specificities, and the uncertainties related to the institutional environment of fair trande market, the contracts alone are not enough to conduct the transactions. Hence, coordination mechanisms, also known as mechanisms of adaptation are adopted based on two forms of private authority. On one hand, there is the authority performed by the certifying organization that constitutes a formal government. It establishes the norms and the production and trade standards in the fair trade of certified products, which leads to selecting the actors in the orange juice supply chain. The formal government also controls demands satisfaction rates and verifies whether the transactions are carried according to pre-established standards. In addition, it offers incentives to the adoption of organic citrus production and to long-term relationships. On the other hand, there is the informal authority: trust. Unlike the former, it is present in some cases and among some specific actors leading to a different way of selecting actors and controlling the factors that were not investigated by the formal government, such as the informal annual supply agreements between citrus farmers organizations and fair trade expert importers.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Análises espectral e simbólica da modulação autonômica cardíaca em repouso e em resposta à mudança postural de idosos saudáveis: comparação entre gêneros
    (Universidade Federal de São Carlos, 2010-05-26)
    Perseguini, Natália Maria
    ;
    Catai, Aparecida Maria
    ;
    https://lattes.cnpq.br/5801652590531684
    ;
    https://lattes.cnpq.br/4760699117769332
    The dissertation consisted of two works. The objective of the first study was to use linear and non-linear methods to investigate the cardiac autonomic modulation in elderly men and women in response to a postural change from the supine to the standing position. Fourteen men (66 ± 3.5 years) and ten women (65 ± 3.3 years) who did not use hormonal replacement therapy (HRT) were evaluated. All volunteers were apparently healthy. The RR intervals (RRi) and the beat-to-beat heart rate (HR) were recorded in the supine and standing positions. The HR variability (HRV) was studied by spectral analysis: low frequency (LF) and high frequency (HF) in absolute units (LF and HF) and normalized units (LFun and HFun) as well as the low frequency/high frequency (LF/HF) ratio. Symbolic analysis (0V%, 1V%, 2LV% and 2ULV% indexes) and Shannon entropy were also calculated for the HRV analysis. Men presented higher LF, LFnu and LF/HF ratio, and lower HFnu and 1V% symbolic index when compared to women in the supine position. Shannon entropy was higher among men than among women in the standing position. During the postural change there were a decrease in LF and an increase in Shannon entropy in the men s group. There was an increase in LFnu and LH/HF ratio as well as a decrease in HF, HFnu and 2LV% symbolic index due to the postural change from supine to standing position in the women s group. In conclusion, women presented a more appropriate response to the postural change than men in the age range studied, showing that the cardiac autonomic modulation may be better preserved in women than in men. Similarly, the objective of the second study was to investigate the HR autonomic modulation in elderly men and women HRT users and no-users by linear and nonlinear methods. So, 15 men (66 ± 3.4 years), 13 women without HRT (64 ± 3.5 years) and 7 women HRT users (61 ± 2.1 years), all of them apparently healthy, were evaluated. The RRi and the beat-to-beat HR were recorded in the supine position. The data analysis was carried out on the same methods described in the first study. The cardiac autonomic modulation analysis in the supine position shows that the women without HRT presented higher HFnu and lower LFnu, LF/HF ratio and 0V% symbolic index when compared to the men. No differences were observed in the comparison between the women who used and did not use HRT. We concluded that the women without HRT seem to have a higher cardiac vagal modulation and a lower cardiac sympathetic modulation when compared to the men. The use of HRT may not offer advantages to the cardiac autonomic modulation in elderly women.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Assimilação por bactérias do carbono e nitrogênio provenientes da matéria orgânica excretada e celular de Planktothrix agardhii
    (Universidade Federal de São Carlos, 2010-05-26)
    Tessarolli, Letícia Piton
    ;
    Vieira, Armando Augusto Henriques
    ;
    https://lattes.cnpq.br/4428377384377272
    ;
    https://lattes.cnpq.br/4024406734152899
    The cyanobacterium Planktothrix agardhii is an important organism for the dynamics of Barra Bonita reservoir due to recurrent blooms throughout the year. However, there are still few published data on the dynamics of polysaccharides degradation and nitrogenous compounds excreted by the cells, as well as the way this process, and the compounds available, may affect the diversity and abundance of the bacterial community. This study aimed, therefore, to determine the feasibility of the released organic matter and cell biomass of cyanobacteria as the sole source of carbon and nitrogen for bacteria. Two similar experiments were performed: one using the dissolved organic matter (DOM) released by P. agardhii as a substrate for the establishment of a community from an inoculum from Barra Bonita reservoir and the second using cellular biomass of cyanobacteria as a substrate. Analysis of carbon and nitrogen, dissolved and particulate, provided the adjustment of a decay kinetic model, while counting and analysis of bacterial morphotypes, along with Denaturing Gradient Gel Electrophoresis (DGGE), were used to establish a possible process of bacterial succession by using these substrates. The settings in the kinetic model showed two phases of degradation for both nitrogen and organic carbon: first, a rapid phase, during the first three days of degradation, followed by a slower phase of degradation. The degradation coefficients of the first phase (kT) reached values up to 60x higher than those determined for the second phase of mineralization (k3). Our values for residual compounds are in agreement with published data on the reservoir, and may have ecological implications for the possibility of export to downstream areas. Bacterial concentrations in number and total biovolume of the samples provided a curve with a peak in the second and third days of experimental culture, followed by a decline, more pronounced in curves of biovolume due to the continuing reduction in the average value per bacterial cell found in cultures. The analysis of morphotypes showed no significant differences through time in cultures with DOM, however, in cultures with bacterial biomass, a reduction in the concentration of bacilli may be observed, with a consequent increase in the concentration of coccobacilli and cocci. A preliminary analysis of the DGGE showed changes in patterns of bands produced between days 1, 3 and 5 in both experiments, which may be indicative of a succession process in these cultures. The use of these sources of carbon and nitrogen by bacteria proved therefore feasible to maintain the bacterial community and a possible succession process has been suggested.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Perfil dos cursos de formação de professores dos programas de licenciatura em química das instituições públicas de ensino superior da região nordeste do Brasil
    (Universidade Federal de São Carlos, 2010-05-28)
    Marques, Clara Virginia Vieira Carvalho Oliveira
    ;
    Ferreira, Luiz Henrique
    ;
    https://lattes.cnpq.br/4819009378941531
    ;
    https://lattes.cnpq.br/0504326528660511
    This study aimed to determine the profile of Chemistry´s courses of Public Institutions of higher education in Brazilian Northeastern, referencing the current educational paradigms and also the legal guidelines regarding processes teacher training governed by the Brazilian education. We attempted to trace the identity of these courses through the perspectives of the adequacy of legal issues and adequacy of the regional reality, understanding the concepts and interactions between faculty and students in the process of training teachers of Chemistry. The methodology was based on the qualitative research structuration, using documentary analysis and content analysis of semi-structured interviews and questionnaires, which were treated under the scheme of the methodology of systemic networks. We studied the Political Pedagogical Project and the Curriculum Matrix for 16 courses in Chemistry from the Northeast, as well as the content analysis of interviews with coordinators and teachers and questionnaires to a graduating students sample. The results showed that the courses are seeking to effect their adequacy, however, was identified a marked segmentation between the training areas of chemical knowledge and pedagogical and still prevailing the model of teacher training based on technical rationality. The Internship and Supervised Practice Component Course as were the dimensions that showed the greatest inconsistencies in the change process suggested by current law. Therefore, the profile of studied courses is not yet equal to that recommended in the new Brazilian education paradigms for teacher training.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Utilização da borracha natural no desenvolvimento de elastômeros termoplásticos
    (Universidade Federal de São Carlos, 2010-05-28)
    Rojas, Galia Johanna Alzate
    ;
    Pessan, Luiz Antonio
    ;
    https://lattes.cnpq.br/8276650236213537
    ;
    https://lattes.cnpq.br/0771017207165419
    Dynamic vulcanization is a process of vulcanization of an elastomer during melt mixing with a thermoplastic. This process results in an elastomeric alloy material with the properties of a conventional thermoset rubber, but which can be processed as a conventional thermoplastic. In this study, thermoplastic elastomers (TPEs) based on natural rubber (NR)/polyprolylene (PP) with various blend ratios were prepared. The TPEs was obtained by dynamic vulcanization of NR/PP using a sulphur (S)/N-tert-butyl-2- benzothiazolesulphenamide (TBBS) and tetramethylthiuram disulphide (TMTD) curative system during processing in the melt state. The crosslinking formation during the processing was confirmed by the increase in the degree of cure of the systems measured by DSC. The dynamic vulcanization process increases the stiffness of the NR phase in the TPEs and modifies the thermal and mechanical behavior. NR/PP TPEs with high content of NR showed superior mechanical performance compared to the uncrosslinked NR/PP blends in terms of tensile strength and Young s modulus. It was obtained an increase in Young s modulus values of NR70/PP30 TPE of 316% than compared to NR70/PP30 conventional blend. The main reason for the high performance was the increase of degree of cure during the reactive processing that became the NR phase more rigid and contributed to the increase in the mechanical resistance of TPEs.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Toxicidade aguda e respostas metabólicas e hematológicas do pacu (Piaractus mesopotamicus, Holmberg, 1887) exposto a concentração sub-letal de triclorfon e recuperação
    (Universidade Federal de São Carlos, 2010-05-28)
    Venturini, Francine Perri
    ;
    Moraes, Gilberto
    ;
    https://lattes.cnpq.br/4427903557163246
    ;
    https://lattes.cnpq.br/7347561381483761
    Parasitosis in fishes is a relevant problem in aquaculture. Besides, the organophosphate trichlorfon (2,2,2-trichloro-1-hydroxyethyl phosphonate) is amongst the most used medicine in farming of fishes. Due to trichlorfon use in fish parasitosis control, including pacu (Piaractus mesopotamicus), in brazilian and worldwide aquaculture, it is necessary to study the effects of this organophosphorus compound related to toxicity and metabolic biochemical parameters. The aim of this work was to evaluate trichlorfon acute toxicity (LC(I)50;96h) to P. mesopotamicus and histopathological effects of this exposition; detect metabolic changes in juvenile pacu (P. mesopotamicus) exposed to trichlorfon sub-lethal concentration (10% LC (I) 50;96h); and evaluate metabolic changes after seven and 14 days of recovery. Estimated (LC (I)50;96h) of trichlorfon to alevin was 0.04mg/L; to juvenile fish was 0.07 mgL-1. Histological evaluation showed adaptive alterations, aiming to limit xenobiotic entrance; liver alterations aimed an increase in blood influx, consequently increasing detoxication; kidney alterations indicate excretion increase and skin presented cromatophore migration to superficial folds. After sub-lethal exposure, pacu presented a decrease in hemoglobin, after seven days recovery it was recorded a decrease in MCH and after 14 days recovery analysis showed a decrease in hematocrit. Metabolic alterations observed after sub-lethal expositions and recovery indicated efforts aiming to homeostatic maintenance trough energy production. Brain and muscle AChE activity decreased, regaining the control values after 14 day of recovery in xenobiotic free water.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Ensino de discriminações condicionais em bebês: avaliação do responder por exclusão e treino de emparelhamento de identidade com diferentes estímulos
    (Universidade Federal de São Carlos, 2010-05-28)
    Garcia, Lucas Tadeu
    ;
    Gil, Maria Stella Coutinho de Alcântara
    ;
    https://lattes.cnpq.br/1673770301699940
    ;
    https://lattes.cnpq.br/3292626740859106
    Studies on learning by exclusion and stimuli equivalence are usually conducted by means of conditional discriminations teaching procedures. Some recent studies have investigated important variables in procedures for teaching conditional discriminations to babies, both for the maintenance of the subjects in the task and for the establishment of conditional responding in babies. Considering the recent advances in the literature and seeking to develop procedures for investigating relational repertoires in infants, two studies were performed. The first study was divided into two parts whose objectives was: 1A) replicating and adapting to the child care center context a study about conditional discrimination teaching by exclusion for a baby of 17 months, in which photographs were used as stimuli and; 1B ) to evaluate the generality of the procedure employed in the previous study. The second study aimed to investigate the effect of using abstract stimuli and toys stimuli on an identity matching teaching procedure. In Study 1A, the three participants were trained a baseline auditory-visual conditional discriminations with familiar photographs. After that subjects were presented to exclusion and learning evaluation trials. The three participants (between 17 and 19 months) learned the baseline conditional discriminations and chose correctly in all exclusion trials, although they have not demonstrated learning by exclusion. In Study 1B the same procedure was used and only two of three children, aged between 15 and 18 months, learned the baseline relations, although all of them chose the correct stimulus in the exclusion trials. There was evidence of learning by exclusion for some children, however, the performance of infants in the novelty control trials suggested that children could be choosing based on such bias. The results suggest that the presented procedure is a useful tool for the study of exclusion responding in babies and thus enables further investigations on the process. In Study 2, two babies of 17 and 20 months were submitted to an identity matching training with abstract shapes or toys used as discriminative stimuli. The stimuli presentation was made by a mechanical apparatus that allowed the exposure of stimuli in closed and open windows. The programmed consequences varied according to the stimuli training condition. Babies have not learned the identity conditional discriminations in any stimuli conditions, although there was a greater number of corrects choices when the stimuli used were abstract shapes. Nevertheless, it was not possible to obtain conclusive evidence about the effectiveness of the use of those different stimuli conditions on the infant s conditional discrimination learning.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Especiação de metais e sua interação com a matéria orgânica dissolvida em um reservatório artificial
    (Universidade Federal de São Carlos, 2010-05-28)
    Tonietto, Alessandra Emanuele
    ;
    Lombardi, Ana Teresa
    ;
    https://lattes.cnpq.br/6737850858443813
    ;
    https://lattes.cnpq.br/3056194008699912
    Environmental degradation of aquatic ecosystems stimulates investigations about the interactions between dissolved organic matter, trace metals and the biota. This study aimed to investigate the speciation of cadmium, copper, lead and zinc in a reservoir subjected to antropic activities. To develop this study, we have chosen Barra Bonita Reservoir (SP), an eutrophic and contaminated ecosystem that receives urban, industrial and agricultural efluents. Water samples were obtained in three locations within the reservoir considering local seasonality (dry winter and rainny summer) during 24 months. The samples were analysed for total, total dissolved, labile and ionic concentrations of the metals, as well as complexation parameters (CL e logK ML) and competition between copper and zinc for the ligands, fluorimetric characterization, and physico-chemical parameters of the water. The results showed a high degree of deterioration of the ecosystem. Independent of sampling location, the concentration order for the metals was Zn>Cu>Pb>Cd (total and total dissolved). In general copper and zinc remained as complexes in the dissolved fraction, while lead was mostly associated with particulate materials. MineqL+ calculations showed that Zn2+ and Cd2+ dominated the labile form, whereas copper and lead remained associated with carbonates. The increased concentration of total dissolved metal showed an increase of copper and zinc complexes, and labile form of zinc and lead. Through principal component analysis (PCA), seasonal influences related to the main sources of metals supply into the reservoir were identified. Metal competition analysis showed that previously added copper affected zinc speciation. However, prior addition of zinc indicated that this metal was complexed by the ligands that were previously available to copper. Nevertheless, no differences were observed in copper speciation. Because the resevoir is subject to intense and frequent cyanobacteria blooms, Cylindrospermopsis raciborskii was isolated from that environment and cultured in the laboratory to obtain its excreted materials. This excreted material was then separated into three molecular weight fractions (> 30 kDa; 30-10 kDa; 10-3 kDa) that were analyzed for complexation capacity (CL e logK ML) with cadmium, copper, lead and zinc, elemental (C, H, N and S) and biochemical composition, fluorescence characteristics and competition for ligands between copper and zinc, and cadmium xvii and lead. The results showed that the fraction >30 kDa and 30-10 kDa had high carbohydrates contents, but low proteins and lipids, whereas for the 10-3 kDa fraction no variation on the biochemical composition was obtained. Fluorescence analysis showed peaks that define proteinaceous materials with 2 5 aromatic rings ususally assigned to be of phytoplankton origin. The CL and logK'ML for the different molecular weight fractions indicated a broad chemical diversity of the ligands that had different affinities for the metals. Metal competition titrations on the excreted material showed that it was only for the >30 kDa fraction that either previously added copper or zinc were complexed by ligands previously available to zinc and copper, respectively. In the 30-10 kDa fraction previously added lead, was complexed by ligands that were available to cadmium. In all fractions no lead complexation capacity was detected when cadmium had been previously added.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Secagem de pimenta dedo-de-moça (Capsicum baccatum var. pendulum) em secador convectivo horizontal
    (Universidade Federal de São Carlos, 2010-05-28)
    Véras, Antonio Onias Mesquita
    ;
    Freire, José Teixeira
    ;
    https://lattes.cnpq.br/2270677706718167
    ;
    https://lattes.cnpq.br/2122563889901240
    The cultivation of pepper is widespread in Brazil since its colonization. This plant, besides being much appreciated in the cuisine has proven pharmacological effects such as lowering cholesterol, inhibiting appetite and the presence of antioxidants such as ascorbic acid and beta-carotene. It is a product whose demand increases every year, but generally still produced handmade diminish the ability of producers to meet the needs of commerce. To contribute to improving the production of pepper dedo-de-moça, it was the behavior of this plant in analyzing the influence of drying process on the nutritional composition and physical qualities of the dried product. For this, drying kinetics were obtained and certain structural properties (apparent density, real density and porosity) as a function of moisture content during drying. Assessing the quality of the final product was performed by quantification of ascorbic acid and study of rehydration. The convective drying and freeze-drying was compared with respect to product quality parameters such as shrinkage, structural properties, vitamin C retention and rehydration characteristics. To describe the kinetics of drying and rehydration were used empirical and semiempirical equations. The characterization of the rehydration process was carried out from the indices that take account of the capacity of water absorption and loss of solutes. The use of seed from the drying of peppers to obtain seedlings was studied by checking the germination through standardized tests. The samples of convective drying at 60 ºC had the best results in terms of nutritional quality, rehydration characteristics and structural properties, comparing with those obtained from freezedrying. In assessing the use of seeds of peppers after processing to obtain new seedlings, the most suitable temperature was 40 oC to cause less damage to germination.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Ecologia trófica e ecomorfologia de peixes em um trecho do Alto Rio São Francisco impactado pela transposição do Rio Piumhi, com ênfase nas espécies Pimelodus fur Lütken, 1874 e Leporinus reinhardti Lütken, 1875
    (Universidade Federal de São Carlos, 2010-05-28)
    Stefani, Patrícia Monte
    ;
    Rocha, Odete
    ;
    https://lattes.cnpq.br/7577441794992601
    ;
    https://lattes.cnpq.br/3840139659511108
    Studies on the feeding of fishes provide relevant information for understanding the mechanisms allowing the coexistence and exploitation of resources by several species of fishes and also by other components of the aquatic communities.. The objective of the present study was to analyze in detail the feeding habits and the ecomorphology of the fish species Pimelodus fur and Leporinus reinhardti as well as to preliminarily characterize the fedding habits and describe the morphological characteristics of other nine species of fish occurring in a stretch of the Upper São Francisco River Basin. Fishes were sampled in four periods: December 2006 and 2008 (rainy periods) and April 2007 and June 2008 (dry periods) using with gillnets, seine nets and sieve. The results on the feeding ecology of P.fur revealed that this species belong to the trophic gulid of the insectivores, since insects represent between 74.0% and 79.0% of its diet. There were seasonal changes in the diet of P. fur, with food items essentially authochtonous, as aquatic insects larvae being consumed in the dry periods and insects from terrestrial sources, as Araneae and Hymenoptera being added to its diet during the rainy periods, in both São Francisco River and its tributary Piumhi River. In these rivers P. fur displayed high trophic specialization, being a specialist in consuming aquatic insects. It was also observed great overlap in the food items consumed by the different size classes of P. population sampled in both rivers. L. reinhardti had intense feeding activity in both seasons dry and rainy periods. This species belong to the trophic guild of herbivores, being its diet composed mainly by plant material. The feeding spectrum of L. reinhardti is wider in São Francisco River than in the Piumhi River, what can be a consequence of the fact that the gallery forest in the São Francisco River is better preserved in this region than that of the Piumhi River. There were seasonal changes in the diet of L. reinhardt, with some food items as Trichoptera and Hymenoptera only being consumed in the rainy periods. There was no significant change in the diet of L. reinhardti along its development, with preference by plant material in all size classes. L. reinhardti is a feeding specialist with narrow niche breath. There was no feeding niche overlap between P. fur and L. reinhardti in any seasonal period or river stretch studied. Although feeding activity of both P. fur and L. reinhardti was intense during all periods analyzed, the narrow feeding niche breath and the large diet overlap among the size classes within each species population indicate that food sources are abundant in this part of the Upper São Francisco River basin. Regarding the morphological characteristics there was also trophic structuring of the species studied in Piumhi and São Francisco Rivers, with segregation between the body shape of the specialists (insectivores and piscivores) and the more generalist feeders (omnivores and herbivores).
  • Loading...
    Thumbnail Image
    Item type:Item,
    Interações e viabilidade do plantio consorciado de pinhão-manso (Jatropha curcas) e girassol (Helianthus annuus L.)
    (Universidade Federal de São Carlos, 2010-05-31)
    Coelho, Ricardo Coeli Simões
    ;
    Gerald, Lee Tseng Sheng
    ;
    https://lattes.cnpq.br/3411283601306914
    With the recent advent of biodiesel in Brazil, there has been a significant increase in the number of research on the potential of utilizing oleaginous as raw material, especially in physic nut (Jatropha curcas L.), due to its superior oil technical characteristics, as well as the plant s hardiness and productivity. However, since the production of physic nut only becomes economically viable from the third year, there is a need to consider planting in intercropping manner. The aim of this study was to evaluate the interaction and the technical and economical feasibility of intercropping of jatropha and sunflower (Helianthus annuus L.), which is also an excellent source of oil for biodiesel production. The project was implemented at UFSCar / CCA in Araras, São Paulo. The jatropha seedlings were planted in May 1998, spaced 2 meters between plants and 4 meters between rows. The sowing of sunflower variety IAC Iarama was done in November 2008, between physic nut lines, with four rows spaced at fifty centimeters, with an estimated 50,000 seeds per hectare. We evaluated the sunflower plant yield, the development of physic nut and the possible allelopathic interactions between cultures. Allelopathic effects between sunflower and weeds were also investigated. We adopted the split-plot design with four replications and four combinations of consortia, whereas T1: growing sunflowers on both sides of the physic nut planting, T2: growing sunflowers west of the physic nut planting with the east side being reserved for the germination of weeds, T3: growing sunflowers to the east line of physic nut with the west side being reserved for the germination of weeds; T4: both sides of the line of physic nut were reserved for the germination of weeds. It was concluded that there was no influence on the development of jatropha vi ii plantations in intercropped with sunflower and sunflower production was not affected by physic nut. There was also a suppression of spontaneous plants in areas with sunflower. The alternative of this consortium demonstrates a good choice for the national biodiesel program.
  • Loading...
    Thumbnail Image
    Item type:Item,
    Organização do trabalho e controle em teleatendimento: o caso de uma empresa de cobrança
    (Universidade Federal de São Carlos, 2010-05-31)
    Ricci, Marlucy Godoy
    ;
    Rachid, Alessandra
    ;
    https://lattes.cnpq.br/6981682198988902
    ;
    https://lattes.cnpq.br/9668886542467621
    The purpose of this study was to explore the peculiarities of the work organization and the different ways of control that were observed in the call center operator s activity. The theoretical-methodological focus that led the research is the Work Organization. A bibliographic research and a case study were performed. The bibliographic research allowed the characterization of the area, its emergence and development, as well as many aspects of the work in this activity. The field research was performed at a company that does collection service over the telephone and involved some visits to the company plant and the incorporation of interviews with the operators, support staff, main executives and operation manager. The interviews allowed the interviewees to explain how they operate, how they evaluate their job, how they deal with different demands and also their perspective regarding the future of this activity. The literature shows that the employees who have contact with the clients, as telemarketing operators, experience a double control, practiced on one hand by the company norms and rules and on the other hand by each client s specific demands. In the studied company it was noticed that the operators, besides the company and the clients, have to deal with other souces of embarassment.
  • «
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • ...
  • 1012
  • »
Siga as redes sociais do SIBi
Contato

Repositório Institucional da UFSCar (RI UFSCar)

Av. Biblioteca Comunitária, Campus São Carlos

Rod. Washington Luís, km 235 - SP-310

São Carlos, SP, 13565-905 (16) 3351-8477

Email: repositorio@ufscar.br

Acessos ao repositorio.ufscar.br
Consultar estatísticas de acesso

DSpace software copyright © 2002-2026 LYRASIS

  • Accessibility settings
  • Privacy policy
  • End User Agreement