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  1. Home
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Browsing by Issue Date, starting with "2011-09-02"

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    A influência do fósforo na toxicidade de cobre e composição bioquímica de Chlorella vulgaris
    (Universidade Federal de São Carlos, 2011-09-02)
    Souza, Imyra Maíra Martins de
    ;
    Lombardi, Ana Teresa
    ;
    https://lattes.cnpq.br/6737850858443813
    ;
    https://lattes.cnpq.br/3930565568802402
    Metal toxicity to microalgae is dependent on environmental conditions, evolutionary history of the microalgae, and previous exposure of the organism to the specific metal. Also, it is importantly influenced by the physiological condition of the algae in the moment of metal exposure. In this research we investigated several combinations of phosphorus (P) and copper (Cu) concentrations on the biochemical composition and Cu toxicity to Chlorella vulgaris. Due to its known toxicity, copper was considered in its free Cu2+ ions specie. Because microalgae physiology reflects the environmental conditions, but it also stores some of the inorganic nutrients, previous to Cu spike in the cultures, the algae were acclimated to each treatment s specific P concentration to be tested in combination with Cu. We considered cells were acclimated to a specific P concentration after its growth rate had been stabilized for at least four generations, always transferring the cells while in the beginning of the exponential growth phase. Biomass and physiological parameters analyzed were cell number (cell.mL-1), chlorophyll-a concentration, dry weight, lipid classes (Iatroscan TLC/FID), and total cellular proteins and carbohydrates at several combinations of P/Cu. The P concentrations tested were 5.0x10-5, 2.5x10-5, 5.0x10-6 and 1.0x10-6 mol.L-1 and the free Cu2+ ions concentrations ranged within 1x10-10 and 5x10-8 mol.L-1, and were determined through ion selective electrode (ISE). Our results showed that Cu toxicity to C. vulgaris increased at low P. Carbohydrate, protein and lipid productions were in general triggered at low P and high Cu, with some exceptions. TAG was the lipid class most affected by stressing situations. AMPL and PL were the lipid classes with the higher percent composition amog the classes; HC, WE and ST were present in minor amounts even under stressing situations.
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    Estudos citogenéticos em espécies das tribos Hypostomini e Ancistrini (Loricariidae, Hypostominae)
    (Universidade Federal de São Carlos, 2011-09-02)
    Rubert, Marceléia
    ;
    Moreira Filho, Orlando
    ;
    https://lattes.cnpq.br/3927076022470557
    ;
    https://lattes.cnpq.br/5065670903691241
    Conventional and molecular cytogenetic analysis were performed on 15 species of the subfamily Hypostominae, comprising 12 species of the Hypostomini tribe, genus Hypostomus, and three of the Ancistrini tribe, genera Ancistrus and Hemiancistrus. The chromosome number of 2n=52 was observed for Ancistrus multispinis (14m+14sm+24st-a), A. brevipinnis (14m+14sm+24st-a) and Hemiancistrus punctulatus (14m+26sm+12st-a). The nucleolar organizer regions (Ag-NORs) and 18S rDNA sites are simple and terminal for species, A. brevipinnis, A. multispinis and H. punctulatus. In these species, it can be seen that the NORs are also CMA3+/DAPI-. As for the heterochromatin, H. punctulatus showed a small amount of this chromosome component, while A. multispinis and A. brevipinnis showed a larger amount, with large blocks on the long arm of some st-a pairs. In turn, the different species of Hypostomus showed a variation from 64 to 82 chromosomes, exhibiting differences in the karyotype formula between species. The NORs were multiple for most species analyzed, with different phenotypes observed in the number and position, which was also confirmed by FISH analysis, showing an interindividual and interspecific variability. In all species, the NORs were also CMA3+/DAPI _. The heterochromatin pattern distribution was different in each species, being another important chromosome marker. Cytogenetic, molecular, and morphometry analysis were performed in the species Hypostomus albopunctatus (Piracicaba river, SP) and H. heraldoi (Pirapitinga river, GO), including those morphologically similar samples present in the Mogi Guaçu river (SP). All individuals had 2n=74, whereas H. albopunctatus showed 10m+20sm+44st-a and H. heraldoi 8m+20sm+46st-a. These two karyotype formulae were found in the Mogi Guaçu river population. Distinct Ag-NOR phenotypes were observed among the three populations and confirmed by FISH. Regarding the heterochromatin pattern, H. albopunctatus presented terminal bands and an interstitial block. In H. heraldoi, the heterochromatin was found widely distributed in the terminal and interstitial regions of some st-a chromosomes. In these species, the NORs were also CMA3+/DAPI _. RAPD analysis and sequencing of the cytochrome oxidase subunit I (COI) gene were carried out in these two species, in the Mogi Guaçu population and in three more species, H. regani, H. margaritifer, and H. hermanni, obtaining the same dendrogram pattern. All species could be differentiated by their COI sequences, resulting in a total of 16 haplotypes. These analyses, combined with the morphometric data, showed that H. heraldoi and H. albopunctatus are two valid species and the specimens from the Mogi Guaçu river still retain some characteristics of H. albopunctatus, and were provisionally designated as Hypostomus aff. albopunctatus. Due to the large number of species currently included in the Hypostomus genus, along with both the intra and interspecific variability in morphology and color pattern, there are often problems in the taxonomy of this group, which can be assisted by cytogenetic data. This study provided new chromosomal data for Loricariidae, being a valuable cytotaxonomic tool for the Hypostomini tribe. The joint analysis of different characters, such as cytogenetic, molecular, and morphometric, allowed a more precise characterization of different populations of Hypostomus species, helping to clarify their validity as distinct evolutionary units.
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    Os Tupi Guarani de Barão de Antonina-SP: migração, território e identidade
    (Universidade Federal de São Carlos, 2011-09-02)
    Almeida, Lígia Rodrigues de
    ;
    Peggion, Edmundo Antonio
    ;
    https://lattes.cnpq.br/9849805103860827
    ;
    https://lattes.cnpq.br/9263580065240516
    This thesis discusses how the Tupi Guarani who live in the district of Barão de Antonima, in the southwest of São Paulo state, conceive their territory in the context of demarcation of indigenous lands. Considering that the area they inhabit is currently undergoing under a process of demarcation. It also reflects how this indians rethink this context of territorial shifts, referring themselves as definers of their territories. And discussing the way how the myth treats about seeking for Lands free from evils. It (re) means locating the place where this land can be found. Not in the east, how the classical biography presents, but in all those places that the ancestors lived in, assuming different ways and contexts. The investigations carried out in the field articulated the bibliography review wish made me believe that if the demarcation of the lands didn't make sense to the Tupi Guarani groups, nowadays it became necessary. It's a way to guarantee inhabitable spaces where those groups would be able to reproduce their life style. This way it's not about the limitation of the movement or the fixation on a delimitated territory, but a way to guarantee that those groups continue to dislocate around a vast territory, circulating around villages and around demarcated indigenous lands.
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    Utilização dos mecanismos de apoio financeiro à inovação tecnológica por empresas de São Carlos - SP
    (Universidade Federal de São Carlos, 2011-09-02)
    Bueno, Alexandre
    ;
    Torkomian, Ana Lúcia Vitale
    ;
    https://lattes.cnpq.br/6407503018881551
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    Deformação da fase dispersa e degradação de blendas poliméricas em extrusora dupla-rosca aberta e fechada
    (Universidade Federal de São Carlos, 2011-09-05)
    Zborowski Sobrinho, Leonardo
    ;
    Canevarolo Júnior, Sebastião Vicente
    ;
    https://lattes.cnpq.br/4153664441338178
    ;
    https://lattes.cnpq.br/4744657966626932
    In order to obtain flexibility of the processing in a twin-screw extruder and operate it as an internal mixer, the second phase dispersion and deformation and degradation were analyzed during processing in an open and closed twinscrew extruder. Three polymer mixtures with different viscosity ratios were reprocessed up to three times. After each reprocessing, samples were collected to in-line characterization in the extruder. Two characterization methods were applied: analyses of second phase deformation via turbidity and degradation analyzes. During measurements, the die pressure was controlled by a PID controller inserted in a software developed to permit the flexibility. In characterization of second phase deformation two discharge methods were used: ramp and step pressure increase and decrease. The level of droplet deformation was observed with a turbidity sensor during the melt flow through the extruder die. In the polymer mixture with viscosity ratio close to 1, the most intense turbidity variation with the die pressure has been detected due to higher reversible droplet deformation, mainly in polypropylene/polystyrene mixture. With high matrix elasticity, it was observed a hysteresis formation of the droplets due to high relaxation time of the matrix chains and with high viscosity ratio the droplet deformation was lower. In in-line degradation characterization, the die remained closed in all experiments, and three modes were applied: constant screw rotation speed, constant die pressure and oscillatory die pressure. Process parameters shifts were observed during experiments, except during high viscosity mixture processing. Immediately after closed die processing, it was applied a melt flow characterization during the melt discharge at constant die pressure. It was detected branching of polyethylene and chain scission of polypropylene and polystyrene.
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    Desenvolvimento de um sistema de produção recombinante de uma cistatina em uma linhagem industrial de Saccharomyces cerevisiae
    (Universidade Federal de São Carlos, 2011-09-09)
    Nakayama, Darlan Gonçalves
    ;
    Fuentes, Andrea Soares da Costa
    ;
    https://lattes.cnpq.br/7234493834465420
    Saccharomyces cerevisiae is the most important microorganism used in alcoholic fermentation process. A strain of Saccharomyces cerevisiae widely used to produce alcohol in Brazil is the PE-2, due to its high fermentation capacity. The goal of this study was to develop an expression system for recombinant proteins using the industrial strain of Saccharomyces cerevisiae, PE-2. The protein chosen to be used as a model for this system was the Cane-CPI-1, an inhibitor of cysteine protease. Initially the construction of plasmids containing CaneCPI-1 gene was performed and yeast cells were transformed with pYADE4-CaneCPI-1 construction. The transformed strain was submitted to expression analyses during batch fermentative process with cell recycle. The recombinant protein was expressed in yeast cells and it was possible to purify the recombinant protein by affinity chromatography on nickel column. This purified protein was immunodetected using a polyclonal anti-CaneCPI-1antibody and monoclonal anti His-Tag antibody, which were also able to detect the CaneCPI-1 in a crude extract from Saccharomyces cerevisiae cells. Assays of inhibitory activity performed with the purified CaneCPI-1 revealed its ability to inhibit the catalytic activity of a cysteine proteinase. This study showed that the use of transformed strain did not affect the fermentation process and that the PE-2 industrial strain of S. cerevisiae can be a viable expression system for recombinant protein production and open perspectives for production of any protein of biotechnological applications during fermentation alcoholic process.
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    Avaliação de parâmetros e produção de materiais de referência de suplemento mineral para nutrientes e contaminantes inorgânicos
    (Universidade Federal de São Carlos, 2011-09-09)
    Silva, Patricia Helena Toniolo da
    ;
    Nogueira, Ana Rita de Araújo
    ;
    https://lattes.cnpq.br/7034773971317045
    This paper was prepared a material candidate for reference material for mineral mixture for dairy cattle. Shape certain analytes Ca, K, Na, P, Cu, Fe, Mn, Mg, Zn and contaminants As, Cd and Pb The material was crushed, sieved until a particle size less than 80μm and packaged. A study was conducted in the best sample preparation through the use of factorial design, planning Doehlert and 4 in a closed system open system experiments. Through a principal component analysis, we chose to sample preparation that was used in 3 mL of HNO3 acid 3mol.L-1 and 1 mL of H2O2 in a closed system. Techniques of absorption and emission spectrometry were evaluated for the determination of analytes in each of the study. Form testing for between-bottle homogeneity and within-bottle homogeneity to check if the sample is homogeneous. Were also carried out tests in the short-term and long-term stability. The values assigned to each analyte were obtained by an interlaboratory collaborative program. In the end, the uncertainties were determined for each stage of preparation of candidate material and obtained expanded uncertainty pair each of the analytes under study.
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    Comportamento em fadiga da liga Ti-6Al-4V para uso biomédico com superfícies modificadas
    (Universidade Federal de São Carlos, 2011-09-09)
    Potomati, Fernanda
    ;
    Alcântara, Nelson Guedes de
    ;
    https://lattes.cnpq.br/3123107570992184
    ;
    Bolfarini, Claudemiro
    ;
    https://lattes.cnpq.br/9231627080617037
    Surface modification in implants is used, basically, to improve osseointegration, which is defined as the intimate contact between bone and implant material, without a soft tissue layer in the bone/implant interface. Titanium alloys, which are the most commonly used materials in the fabrication of hip stem, have an excellent biocompatibility. The surface modification of these materials can lead to a better osseointegration. The developments and studies of new modification processes are very dynamic and often related to biological aspects, for example, cellular growth on the modified surface. Studies regarding engineering and properties of the implant with modified surface are not up to date with the quickness of new processes developments and evaluation of these processes on cellular response. Since fatigue is a determinant property of implants, this study aims to evaluate the fatigue behavior of Ti-6Al-4V alloy with modified surfaces by laser and anodic oxidation. Thus, axial fatigue tests were performed to obtain SxN curves (Stress x number of cycles) of cylindrical specimens, in the polished and surface treated conditions. Roughness measurements and scanning electron microscopic (SEM) were used to characterize the features of the modified surface. As a result, the modification by anodic oxidation, for the parameters used, did not affect the fatigue behavior of Ti-6Al-4V alloy. Unlike anodic oxidation, the laser surface modification performed in this work decreases by about 30% the limit of fatigue strength of the alloy.
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    Os princípios de psicologia de William James: compromissos e consequências de uma filosofia da ação
    (Universidade Federal de São Carlos, 2011-09-10)
    Bertoni, Paulo Gilberto
    ;
    Pinto, Débora Cristina Morato
    ;
    https://lattes.cnpq.br/1311151012002541
    ;
    https://lattes.cnpq.br/4296933977075708
    This work analyzes the psychological texts of William James (1842-1910), specially his Principles of Psychology, published in 1890. We begin following an alternative itinerary of reading proposed by James in the preface of the book, which also allows us to understand how the New Psychology has influenced the construction of psychological field in 19th century. We present this in our first chapter trying to show what we call a theory of action. In the second chapter, the previous conclusions are articulated with James exposition of the thought as a stream and with his considerations of the Self. In the third, we investigate the relations between his psychology of cognition and his posterior epistemology. Finally, we postulate that The Principles must be understood as a psychology of action, which has its basis in a philosophy of action incorporated, consciously or not, by James. We emphasize onward the research the tension created between the dualistic point of view assumed by James and the conclusions suggested by a closer reading.
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    Aplicação de metodologias para análise e previsão do preço do fruto de açaí
    (Universidade Federal de São Carlos, 2011-09-13)
    Eder, Karina
    ;
    Pessoa, José Dalton Cruz
    ;
    https://lattes.cnpq.br/4212703554284544
    ;
    https://lattes.cnpq.br/5358203242004730
    Açaí is the fruit of a palm tree found throughout the North of Brazil that has been gaining attention due to its high energetic potential, applications in pharmaceuticals, dentistry, medicine and food industries. So, consumers from all over Brazil and also from other countries are looking for the product, encouraging the extraction and the increase in planted area causing inflating the price. Being a market with strong growth can be invaluable for the agribusiness, producers and middlemen predict the price of fruit. Given this context, the objective of this study is to analyze and predict the price of açaí fruit sold at the Açaí Fair in Belém (Pará), through the following methodologies: time series, specifically ARIMA and SARIMA models and technical analysis using tracking trends and chart Candlestick. The series analysis showed that there is a growing trend of prices and annual seasonality. The results showed about forecast presented Root Mean Squared Error and Mean Absolute Percentage Error low. As for price trends, can be observed that the use of moving averages and MACD with the suggested parameters were the methods that best indicated the beginning of the season and offseason and were able to track the price change, being considered for use as an effective tool of aid in decision making. But the use of exponential moving averages and the intersection of three moving averages, and/or the method of Didi Index, showed that the tool can track the price change, but does not anticipate the entry of season or offseason, being ineffective for use in decision making. So, we conclude that the use of only method to predict the price can be ineffective to assist in decision making, and therefore requires the use a set of methods.
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    Biologia de Semiaphis dauci (Fabricius, 1775) e Aulacorthum solani (Kaltenbach, 1843) (Hemiptera: Aphididae) associados à Arracacia xanthorrhiza (Bancroft, 1825)
    (Universidade Federal de São Carlos, 2011-09-14)
    Takada, Hélio Minoru
    ;
    Silva, Carlos Roberto Sousa e
    ;
    https://lattes.cnpq.br/4890369735136839
    ;
    https://lattes.cnpq.br/1676907711772667
    The aphids are limiting for various crops, and in the case of the horticulture crops, it has been a problem for the cultivation of Arracacia xanthorrhiza (Bancroft, 1825), the arracacha. This plant, of Andean origin, has been well adapted to these climatic conditions of Southeast Brazil and conquered many consumers, currently representing an important food source due to its taste and nutritional value, thus providing a considerable income to small farmers. It is largely cultivated in the South and Southeast regions in Brazil. Although this culture is considered rustic, aphids has been causing great damage to its development. In the present work, the influence of temperature on the development of Semiaphis dauci (Fabricius, 1775) and Aulacorthum solani (Kaltenbach, 1843) was studied. The nymphal development period of S. dauci and A. solani on A. xanthorrhiza was of 23.84 and 33.02 days at 10 °C and 6.7 and 10.04 days at 25 °C, respectively. The minimum thermal threshold of development for the nymphal stage of 4.59 and 4.33 °C, the thermal constant 138.12 and 142.86 degrees-days and the approximate upper limit temperature ranged from 25 to 28 and 27 °C, respectively. The life table parameters indicated that temperatures of 22.5 and 25 °C provided the best thermal conditions for the S. dauci population growth, resulting the highest value of intrinsic rate of natural increase (rm=0.15), the lowest average value of the generation of 10.38 and 8.47 days and the shortest doubling times for the population with 4.74 and 4.55 days, respectively. The observed biological aspects indicate that A. solani has great potential for the population growth and a preference for smaller temperatures than S. dauci, and can be considered a potential pest for A. xanthorrhiza. The infestation of S. dauci in this species also causes severe damage to the plant, nevertheless other factors such as formation of dense colonies, lower mobility, and the action of toxins and viruses may also involved.
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    Atividade metaloproteinases e propriedades físicas, químicas e biomecânicas de ossos de ratos tratados com cloreto de mercúrio
    (Universidade Federal de São Carlos, 2011-09-15)
    Dávila, Fernando Vidal
    ;
    Nonaka, Keico Okino
    ;
    https://lattes.cnpq.br/7711249418825579
    There are few data about the mercury influence on bone metabolism them it is important to investigate the bone parameters that can be affected by it. The aim of this study was to evaluate the biometric, physical, biomechanical and enzymatic (MMPs) bone alterations in adult rats contaminated with mercurous chloride (HgCl2) during their development. The animals were separated in 4 groups: 3, 6, 9 and 12 months. The animals received mercuric chloride (experimental group) and saline (control group) by stomach gavage. The treatment had begun on 30 days of animals life, 5 times a week during 60 days. The daily dose was 5mg/kg of body weight of HgCl2 and 0,1ml of saline /100g of body weight. The animals were weighted 3 times a week until the sacrifice day. After the period of contamination, the 3 months groups were sacrificed, while the other groups stayed without treatment to complete their ages (6, 9 and 12 months). The animals femurs, tibia and vertebras (L5) were dissected to be analyzed on biometric, biomechanical and enzymatic parameters. To statistical analyze it was used the normality test Shapiro-Wilk, the variance tes Two-way analysis (ANOVA) (for time and treatment), and the Tukey Test to do multiple comparisons using Graphpad Instat (version 3.00 December 1997). All the values were expressed as media ± standard error media and the significance level was p ≤ 0.05. There was a tendency of a percent increase of mineral material, mineral and bone density and of the maximum force of femurs sample on contaminated groups related to their respective controls. The contaminated animals showed difference on the maximum force of the vertebras, which the 6 months had a higher value than the 3 months group. It was higher MMP-2 activity on mercury group than on the saline group with the same age. The results showed that the HgCl2 on 5m/Kg dose, when related to the control group, did not present difference of biometric, biophysical and biomechanical parameters on bone tissue of rats in development. The HgCl2 contamination stimulated the MMP-2 activity at the end of the contamination period and remained until 6 months after the contamination.
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    CeO2 - 10% MOL Gd2O3: efeito da codopagem com X% MOL Sm2O3 (O5 X 52) na microestrutura e na condutividade elétrica
    (Universidade Federal de São Carlos, 2011-09-16)
    Araújo, Huyrá Estevão de
    ;
    Souza, Dulcina Maria Pinatti Ferreira de
    ;
    https://lattes.cnpq.br/4100119317525940
    ;
    https://lattes.cnpq.br/1803384161648735
    Fuel cells are the most promising technology for producing clean energy. In particular, the Solid Oxide Fuel Cell (SOFC) stands out among the various types due to high efficiency at high temperatures (800 ~ 1000°C) resulting in high cost for power generation. The operating temperature decreasing allows the use of non expensive materials and increases cell life time. One of the challenges for reducing the operating temperature is to increase the electrical conductivity of electrolytes. In this context, the ceria-based electrolytes are an alternative due to its high ionic conductivity at intermediate temperatures (500 ~ 650 °C). In this work, commercial powder of 10 mol% Gd2O3 doped Ceria was co-dopped with X% Sm2O3 (0
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    Efeitos do treinamento resistido sobre o estresse oxidativo no fígado de ratas ovariectomizadas
    (Universidade Federal de São Carlos, 2011-09-16)
    Rodrigues, Maria Fernanda Cury
    ;
    Perez, Sergio Eduardo de Andrade
    ;
    https://lattes.cnpq.br/9408953831211309
    ;
    https://lattes.cnpq.br/8239825852579803
    Estrogen deficiency is associated with increased oxidative stress (OS), which in turn is involved in the physiopathology of diseases such as fatty liver disease (NAFLD). Resistance training (RT) may reduce the oxidative damage by promoting an up-regulation in the antioxidant defence system. Therefore, this study aimed to assess the effects of RT on OS markers in the liver of ovariectomized rats (Ovx). Adult Sprague-Dawley rats were divided into four groups (n = 8 per group): sham-operated sedentary (Sham-Sed), ovariectomized sedentary (Sed-Ovx), sham-operated resistance training (Sham-Rt) and ovariectomized resistance training (Ovx-Rt). During a 10-week RT period, the animals climbed a 1.1 m vertical ladder with weights attached to their tails; the sessions were performed three times a week, with 4-9 climbs and 8-12 dynamic movements per climb. The OS was measured by levels of reduced glutathione (GSH) and oxidized glutathione (GSSG), the enzymatic activity of catalase (CAT) and superoxide dismutase (SOD), the lipid peroxidation (LP), the concentration of vitamin E and gene expression of glutathione peroxidase (GSH-Px). The estrogen deficiency associated with Ovx decreased in the GSH/GSSG ratio (28%), vitamin E concentration (45%), and gene expression of GSH-Px (49%). Moreover, the training induced negative changes in the hepatic anti-oxidative/oxidative balance, as evidenced by the increased TBARS levels (30%), as well as decreased GSH/GSSG ratio (19%) and vitamin E concentration (35%). These data indicate that the RT program adopted did not reverse the hepatic oxidative damage caused by Ovx; indeed, it increased hepatic OS.
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    Desenvolvimento de compósitos biodegradáveis a partir de amido termoplástico e fibras vegetais
    (Universidade Federal de São Carlos, 2011-09-16)
    Carmona, Vitor Brait
    ;
    Mattoso, Luiz Henrique Capparelli
    ;
    https://lattes.cnpq.br/5839043594908917
    ;
    https://lattes.cnpq.br/4982149954130302
    This project had as main objectives to obtain and to develop new and biodegradable composites from renewable sources using a thermoplastic starch (TPS) matrix reinforced with different amounts of natural fibers, acuri, carandá and gravatá. Initially, these fibers were extracted and characterized, which are still unknown to the scientific community their potential use in composites. The characterization were realized by themorgravimetric analysis (TGA), tensile test, chemical characterization by determination of their main constituents and infrared spectroscopy (FTIR), and morphological and structural analysis by xray diffraction (XRD) and scanning electron microscopy (SEM). The fibers had thermal stabilities similar to each other with their initial temperature of thermal degradation in the range of 250 °C. The fibers show a brittle behavior when subjected to tensile tests, and it were determined elastic moludus and tensile strength in the range of 13 to 50 GPa and 180 to 580 MPa, respectively and, both thermal and mechanical stability are in according to those conventional natural fibers. It was possible to determine the crystallinity index of the fibers by XRD, and SEM images show the fibers surfaces. Four composites formulations were obtained and processed based on four different fibers content (5%, 10%, 15% and 20% w/w), and were evaluated as a function of fiber content water absorption properties, thermal and mechanical stability, and morphological and structural characterization by SEM and XRD. The thermal stability and morphology of TPS homogeneous matrix weren t influenced by the presence of natural fibers, besides the absence of new crystalline structures by XRD. The presence of fibers reduced material water absorption. Mechanical properties such as elastic modulus and tensile strength increased with fiber content, especially at levels above 10% w/w, and the viscosity of the molten also have increased with fiber content. Overall, it was possible to extract and to characterize new natural fibers and use them in a TPS matrix, obtaining new biodegradable composites by conventional processing methods.
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    Nanotecnologia: indicadores tecnológicos sobre os avanços em materiais a partir da análise de documentos de patentes
    (Universidade Federal de São Carlos, 2011-09-19)
    Milanez, Douglas Henrique
    ;
    Gregolin, José Angelo Rodrigues
    ;
    https://lattes.cnpq.br/7842651773105125
    ;
    https://lattes.cnpq.br/9233120345793647
    Nanotechnology is a technological advance of several fields, regarded to be emergent, universal and diffuse field, involving mainly the development of nanomaterials, which can show different properties and behaviors. The possible impact in the society sustainable development becomes important the monitoring of nanotechnologies and nanomaterials in order to provide subsidies for planning and decision making. In this research, the advances in products, process and materials in nanotechnology and nanocelulose were mapped using patent indicators. The technological progress in nanotechnology was concentrated in 1999-2008, involving mainly China, Korea, USA and Japan. The most important domains in nanotechnology development were Chemistry- Materials and Eletronics-Eletricity, emphasizing the Semiconductors and Materials-Metallurgy subdomains. The largest patents holders in nanotechnology are mainly Asian, highlighting both companies and universities. In the Brazil, the nanotechnology developments were depended mainly on universities and research centers. To nanocelulose, Japan and USA were prominent and most of the patents applications were related to processing of cellulose pulp and the potential application of nanocelulose was associated to composites, paints, cosmetics, pharmaceuticals and foods. No important patent documents of nanocellulose technologies were identified in recent years, although the patenting of universities increased. In Brazil, most of the patent documents in nanocelulose are in the public domain and technology developed by Brazilian focus on processes for obtaining nanocellulose from bacteria. The outcomes suggested that monitoring and technological forecasting research of nanotechnology is necessary a sectorial analysis. Furthermore, methodological improvements were designed through the automation of recovery, treatment and filtering of information, which allowed advances in monitoring and technological forecasting methodologies.
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    Estudo comparativo entre as tecnologias via úmida e via seca para a preparação de massas de porcelanatos
    (Universidade Federal de São Carlos, 2011-09-20)
    Melchiades, Fábio Gomes
    ;
    Boschi, Anselmo Ortega
    ;
    https://lattes.cnpq.br/3259846931278607
    ;
    https://lattes.cnpq.br/4469106561041487
    Considering the growth of the Brazilian ceramic tiles sector and its expressivity in the global setting, the present work has been developed in order to evaluate the main differences related to the preparation of bodies compositions by dry and wet route technologies and then to contribute to the viability of the porcelain tiles fabrication by dry route. The dry route can be considered the greatest technological innovation of the Brazilian ceramic tiles industry. However, despite the importance of this route to ceramic tiles fabrication, just few scientific studies were performed in order to identify its advantages and disadvantages. At the same time, in the last ten years, the porcelain tiles production showed a large growth, related to the global tendency in the sector to the diversification of production. The porcelain tiles present excellent technical properties and aesthetics effects to allow the development of ceramic products with high added value. These products have shown good penetration on market segments that are not achieved by traditional ceramic tiles. To the development of the study, it was evaluated the influence of the technology of preparation of bodies compositions on several technological parameters of relevance to the ceramic tiles production, like the medium size and the particle and granules sizes distribution, the particle and granules shapes and the degree of mixture. After that, tests were performed related to the bodies chemical compositions, the conditions of milling and granulation by dry route, to identify the necessary adjustments to feasible the porcelain tile production by this route. The results interpretation allowed to understand the importance of the technological parameters evaluated, contributing for a critical evaluation of the feasibility of producing porcelain tiles by the dry route.
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    Desempenho de meios filtrantes na filtração de gases a altas pressões
    (Universidade Federal de São Carlos, 2011-09-21)
    Tanabe, Eduardo Hiromitsu
    ;
    Coury, José Renato
    ;
    https://lattes.cnpq.br/9778700143605069
    The presence of residue in the transport of natural gas in pipelines may result in numerous losses for the gas companies, such as obstruction of measuring equipment, decrease in product quality, and reduction in the lifetime of equipment. A very efficient and inexpensive way for removal of particles is the use of gas filtration. Despite the wide applicability of filters, there are very few studies on natural gas filtration, due to their operating conditions, because they work at high pressures. Thus, research in this area is extremely important to obtain more information about this subject. Therefore, this study aimed to examine the behavior of different filter media used in gas filtration at high pressures. The particulate matter used was the phosphate concentrate and the filter media were polyester, polypropylene, cellulose and metal. The absolute pressure of the system varied from 93 kPa to 693 kPa and the volumetric flow from 14 l/min to 74 l/min in the permeability trials and the fluid used was compressed air. The system pressures of 193, 393 and 693 kPa were used in the filtration trials and the superficial gas velocity was kept constant at 0.05 m/s. The results showed that the permeability constants, k1 and k2, did not present significant variations with the increase in the system pressure, that is, the values tended to a constant value. Simulations to determine pressure drop using natural gas as fluid were performed considering that the permeability constants did not present large variations. The results indicated that the increase in system pressure resulted in greater filtering capacities for a given pressure drop. It was observed that the highest absolute pressure applied to the system (693 kPa) provided the lowest pressure drop at the filter for the same powder mass collected in the filtration trials. An analysis of the dust cakes porosity revealed that the increase in pressure resulted in more porous cakes which were less resistant to gas flow. Also, it was verified that the increase in the system pressure provided an increase in the fractional efficiency of the filters for particles smaller than 5 μm.
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    Juntos mais desiguais: um desejo de "nação" paulista não-realizado
    (Universidade Federal de São Carlos, 2011-09-21)
    Magri, Mailce
    ;
    Escudeiro, Richard Miskolci
    ;
    https://lattes.cnpq.br/1623888309974862
    ;
    https://lattes.cnpq.br/2069929216797979
    Assuming that every nation is an imagined community concept created by Benedict Anderson in his book Imagined Communities I propose a discussion about the existence of different projects for the construction of a Brazilian nation, paying special attention to a "Sao Paulo state project". As guideline, I use the subaltern studies, which question the hegemonic centers' theoretical colonialism and the modernity dominant conceptions. This dissertation is based on the subaltern studies literature and on the selection of texts from the period chosen for this study: the years between 1870-1922. These analyses intend to show the existence of a "Sao Paulo project" for the nation, which demonstrates a "admiration" for the North- American racial segregation. This "admiration" was a common theme in many papers written after such project failed.
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    Produção, isolamento e identificação de metabólito com atividade citotóxica de cultura de Streptomyces carpaticus
    (Universidade Federal de São Carlos, 2011-09-21)
    Ferreira, Douglas
    ;
    Badino Júnior, Alberto Colli
    ;
    https://lattes.cnpq.br/6716019534474825
    This study addresses the production, isolation and identification of the substance present in culture broth of Streptomyces carpaticus which showed high biological activity against human tumor cell lines HL-60 (promyelocytic leukemia), MDA-MB 435 (breast carcinoma ), HCT-8 (colon carcinoma), SF-295 (glioblastoma). Cultures of Streptomyces carpaticus in culture medium DSMZ 65 were performed in shake flasks. Initial bioassays of the culture broth extracts showed antiproliferative activity close to 100% inhibition against the tumor cell lines. In order to obtain greater volume of culture medium to isolate the compound of interest, bioreactor cultivations were performed in bioreactor with 12 L working volume. After microfiltration and ultrafiltration of the culture broth through a 0.22- micron and 3 kDa membrane filter, the retentate was then subjected to partitioning using different organic solvents (ethyl acetate and n-buthanol). The fractionation of the extracts was bioguided based on the bioassay results and on HPLC-DAD-MS analysis. The fractionations led to the isolation and identification of the cyclodepsipeptide Valinomycin as responsible for cytotoxic activity. In addition, the results showed the strain as isopalmitic acid producer. Values of inhibition concentration (IC50) obtained for the compound isolated from the broth, against various tumor cell lines, presented low values ranging between 2 and 10 ng.mL-1. The use of bench scale bioreactor, bioguided fractionation and mass spectrometry proved to be fundamental to the development of this study, because it was evidenced that the discovered compound responsible for the antiproliferative activity is produced at very low concentrations. The use of HPLC-DADMS/ MS by selective ion monitoring was able to propose a methodology to estimate Valinomycin production in four different culture media tested, an important result for future studies regarding the development of the production and purification process of Valinomycin by S. carpaticus.
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