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O treinamento resistido promove modulações gênica e proteica de sinalizadores do metabilismo glicolítico no fígado de ratas ovariectomizadas
(Universidade Federal de São Carlos, 2014-07-12)
Tomaz, Luciane Magri
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Perez, Sergio Eduardo de Andrade
;
https://lattes.cnpq.br/9408953831211309
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https://lattes.cnpq.br/8430651176725216
Menopause is associated with higher risks of metabolic changes that may compromise women s life quality. Glicemia is regulated by the liver which is responsible for glucose storage at postprandial and for glucose efflux in a fastened state. The absence or the reduction of stradiol levels cause glucose intolerance and deregulated insulin output in bloodstream, setting of the insulin resistance process (RI). Hepatic glucose regulation is directly related to the accurate control of gene expression which encodes different isoforms of oxidation proteins and glucose input proteins. Studies suggest that Resistance Training (TR) prevents RI on ovariectomized (Ovx) rats liver. However there are few molecular events that support TR. Objective: To investigate the Ovx and TR effects over protein and gene expression of biomarkers associated with insulin signalization and glucose oxidation in rats liver. Methods: Adults Sprague-Dawley were divided into 4 groups (n=6 each group): Sedentary Sham-surgical (Sham-Sed); Sedentary-Ovx (Ovx-Sed); (Sham-Tr) and (Ovx-Tr). Tr protocol included 1.1 m vertical climbing with tied weight to the rats tail. Each session consisted of 4 to 9 climbing and 2 minutes of resting between the exercises. Training was performed 3 times a week during 10 weeks. Gene expression was analysed using real time quantitative PCR and protein assays by Western Blotting technic. Results: GLUT2 gene and protein expression and PGC-1α gene expression increased significantly; and p-Akt Ser473 protein expression decreased in Ovx group. TR promoted a greater increase of PGC-1α gene expression and further repair of GLUT2 gene and protein expression and p-Akt Ser473 protein expression. Conclusions: The results show the ovariectomy promotes overexpression of molecular markers that induced RI. These findings suggest that TR may play an important role on the RI prevention in Ovx animals through gene and protein expression repairment of the glycolytic metabolism signalling molecules.
Manejo e conservação da agrobiodiversidade no assentamento rural Olga Benário no estado de Sergipe
(Universidade Federal de São Carlos, 2014-07-14)
Almeida, Ana Cristina Oliveira de
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Schlindwein, Marcelo Nivert
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https://lattes.cnpq.br/9690898537150950
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https://lattes.cnpq.br/5341111069893881
The paradigm of the rural development through globalization of agricultural markets has affected the diversity of natural resources and, on the condition of the rural settlements, this situation of loss becomes worse seen the heterogeneity of subjects and the existing structural difficulties. This work aims to analyze through native seeds the local conservation of agricultural biodiversity and the management carried out by the settled farmers in Olga Benário Settlement Project located in Sergipe. Two systems of different treatments were identified and, through indicators of low, medium and high levels of agroecosystem analysis was conducted. In large lots, crops which showed more diversity were the fava bean, maize, bean, cowpeas, cassava, bananas, yam and sweet potato. Highlighting the cultures of cassava which showed that seed exchange network established. The absence of an irrigation system and sufficient supply of fertilizer for the production have been identified as limiting factors for further integration of production. Farmers were presented as potential guardians of seeds, as noted in the analysis of the exchange of cassava manivas network which was more significant in relation to other cultures. The construction of Agroecology is seen as the way for the local knowledge reframing agriculture are transmitted, starting with the rescue of native seeds.
Obtenção e caracterização de nanocompósitos de poliuretano termoplástico reforçado com nanocristais de celulose
(Universidade Federal de São Carlos, 2014-07-15)
Prataviera, Rogério
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Lucas, Alessandra de Almeida
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https://lattes.cnpq.br/9754332336954137
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https://lattes.cnpq.br/5895158357997353
In this study the potential of cellulose nanocrystals (CNC) as a reinforcement of a thermoplastic polyurethane partially obtained from renewable sources (Bio-TPU) was investigated. The nanocomposites were obtained in the melt state and from solution casting. The CNC were obtained from acid hydrolysis of eucalyptus kraft pulp. They were freeze dried and used with and without surface treatment. Two types of surface treatment were employed: polymer grafting and oligomers grafting. Only the effectiveness of the second treatment could be confirmed by FTIR. CNC’ structural and geometric characteristics, crystallinity degree and thermal stability were determined by infrared spectroscopy (FTIR), transmission electron microscopy (TEM), wide angle X-ray diffraction (WAXD) and thermogravimetric analysis (TGA), respectively. The concentrations of CNC were varied between 0.1 and 5.0 wt %. The rheological properties of the nanocomposites were evaluated in the steady state and oscillatory measurements in order to evaluate the level of dispersion CNCs in TPU. The nanocomposites obtained by solution casting showed good dispersion. In the melt state, only those obtained with treated CNC showed good dispersion. The deformation and elastic recovery of the nanocomposites tests in the melt state were evaluated through creep and constrained recoil rheological essays. Their morphologies were studied by small angle X-ray scattering (SAXS) and scanning electron microscopy (SEM). It was possible to prove the inclusion of CNC in TPU did not change its conformation. The nanocomposites were also characterized according to their: i) mechanical properties, through tensile tests, ii) thermal properties, by using differential scanning calorimetry (DSC) and TGA, iii) thermo-mechanical properties, evaluated by dynamic mechanical thermal analysis (DMTA) and iv) optical properties, through opacity the nanocomposites with 5.0 wt % of CNC shown better performance and similar results were found from solution casting and melt state processing techniques.
Preparação de vidros e vitrocerâmicas no sistema SbPO4-PbO-ZnO dopados com manganês e ferro
(Universidade Federal de São Carlos, 2014-07-15)
Siqueira, Renata Fernandes
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Nalin, Marcelo
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https://lattes.cnpq.br/3349586880746735
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https://lattes.cnpq.br/6645436997641022
In the present research project a new glass composition containing SbPO4 ZnO PbO was obtained by melt quenching technique. After a brief study of the matrix, a composition was chosen and doped with MnO e Fe2O3 in quantities varying from 0 to 20 mol%. The next step was to perform a heat treatment above glass transition temperature in order to produce glass-ceramics from the obtained glasses. Then, the vitreous materials were characterized by thermal analysis (DSC), and the structural study of the materials was done using absorbance spectroscopy in the UV-vis-NIR and Raman, besides the electronic paramagnetic resonance (EPR) and fluorescence measurements. Refractive index was measured by M-Lines spectroscopy. The new materials were also characterized by X ray diffraction (XRD), optical microscopic and scanning (SEM) and transmission electronic microscopic (TEM). Finally, magnetic measurements were performed in a magnetic force microscope (MFM). The prepared glass samples have a high refractive index and thermal stability over 100 °C, which may be interesting for optical fiber synthesis. After addition of the paramagnetic metals (Mn, Fe), the thermal stability increased even more. The optical analysis of the manganese doped glasses showed that the ions are in the Mn2+ oxidation state, but after heat treatment the color of the glass changes since a small amount of the dopant cation is oxidized to Mn+3 and some magnetism characteristic may be observed. Even though the optical properties were not good with addition of manganese and iron, the sample showed a significant magnetic response. These results of magnetic analysis are promising for the advance of spin-photonics and may be suitable to design devices for information storage.
O fazer do intérprete educacional: práticas, estratégias e criações
(Universidade Federal de São Carlos, 2014-07-16)
Santos, Lara Ferreira dos
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Lacerda, Cristina Broglia Feitosa de
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LACERDA, C. B. F. de
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https://lattes.cnpq.br/7312070448044165
This research aimed to analyze and discuss the work of the Educational Interpreter (IE), which is a recent professional in our country, and the currently researches on their performance in the classroom are incipient in order to better understanding of the practices, strategies and creations in the process of translation and language interpretation to/from Brazilian Sign Language. This thesis aimed to uncover what is behind the work of interpretation from one language to another, what factors influence either positively or negative, the performance of the IE, considering the authorship, the another s discourse, the polysemy of the language involved, and, specially, the creation or transcreation. This research is based on Bakhtinian theoretical frameworks (2009, 2010), because we believe that the language is a concrete activity and is related to life and its character is dialogic. It is not possible the understanding of the IE performance unless with unique acts, which are possible in a specific time and space with real interlocutors that enunciate and expect answers. In order to embrace the entire events surrounding the IE s work (even aware of the impossibility of it), this research were conducted as a qualitative investigation influenced by microethnographic approach. The data collection was done over the second semester of 2011 and it s been observed four IE during their work in four different classrooms, whose classes were taught by three teachers from the final years of elementary school in an Inclusive Educational Program school and bilingual teaching for deaf. In order to tape-record the natural and quotidian situations of the translation process conducted by the IEs we followed the classes and everything that happened during the classes. From the data collected it has selected nine episodes to be analyzed, which were divided into three main axes, titled: the collective construction of knowledge in a context of dialogue-education ; narrative supported by imagetic representations . The analysis and reflections on the IE s performance led us to the construction of a thesis that the work of Educational Interpreter is not restricted to the utterances translation and interpretations. Its daily practices go beyond this aspect. The Educational Interpreter is co-author of the discourses delivered by teachers in classroom. We assume that the classroom context is so complex that the teachers utterances would be untranslated (as some on the translation field authors have said), not because of linguistics issues or by their way of presentation, but because of lots of elements involved. Finally, we list some notes that were relevants to the Educational Interpreters training in order to contribute to these professionals from new perspectives.
Síntese, caracterização e estudo de nanômeros de silício como reforço mecânico em resinas acrílicas a base de PMMA
(Universidade Federal de São Carlos, 2014-07-17)
Lourenço, Rodrigo Vinicius
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Leite, Edson Roberto
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https://lattes.cnpq.br/1025598529469393
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https://lattes.cnpq.br/2428327594608532
The search for improvements in material properties has been studied extensively and fabrication of polymeric nanocomposites stands out for having excellent mechanical properties. In this work, silicon nanomers were prepared by solgel process and grafted in a poly(methyl methacrylate) (PMMA) matrix by powderliquid polymerization, a very common process in prosthodontic procedures to polymerize acrylic resins. Two different types of nanomers were prepared: nanoparticles of silicon dioxide (NPs SiO2) from the tetraethylorthosilicate (TEOS) as precursor and molecules of polyhedral oligomeric silsesquioxane (POSS) from the methyl trimethoxysilane (MTMS), both using the silane coupling agent 3-(trimetoxisilil) propyl methacrylate (TMSPM) also as precursor. The nanomers were produced at different concentrations and embedded in the polymeric matrix after 1 and 7 days to form the PMMA/SiO2 and PMMA/POSS nancomposites. They showed different mechanical behavior with respect to present concentration in the matrix, for PMMA/SiO2 nanocomposites best results were obtained for flexural strength, flexural modulus, yield strength and surface microhardness at low concentrations (less than 1%), while PMMA/POSS with about 1,5% presented better results for flexural strength, flexural modulus and microhardness. In addition, there was a decline to almost all the observed results for the nanocomposites prepared after 7 days compared to those prepared after 1 day, regardless of nanomer and concentration.
Tratamento físico-químico e cultivo de Desmodesmus subspicatus em vinhaça de cana-de-açúcar
(Universidade Federal de São Carlos, 2014-07-18)
Mattos, Luiz Felipe Arjonilla de
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Bastos, Reinaldo Gaspar
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https://lattes.cnpq.br/9329363278429665
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https://lattes.cnpq.br/8003605971716221
The traditional processes of biological dispollution of agro industrial waste water use aerobic and/or anaerobic systems, which generate biomass without commercial value and inevitable effluent nutrient losses. Alternatively, it s being studied the microalgae and cianobacteria application for a potential protein, lipid and other biomass constituent production for a minimization of the pollutant impact and as a way of valuating the residue. This way, heterotrophic cultivation of microalgae, is a proposal that could increase the viability of waste water treatment, once it uses organic compounds for the growth of this microorganisms in absence of light, being researched together with the bioremediation of effluents. Vinasse is a waste water highly produced in the fermentation-distillation process for the sugarcane based ethanol production. Depending on its biochemical composition in terms of organic matter and nutrients, the use of vinasse appears to be attractive as a substrate for biotechnological process development. Besides, physical-chemical treatments like pH adjusting and suspended solids flocculation must be studied for its use viabilization. D. subspicatus is a Chlorophyceae which has presented high cellular viability in cultivations using domestic and industrial waste water as substrate, easily tolerating temperature and pH variations. This said, this study aimed the the physicalchemical treatment of coagulation-flocculation and the heterotrophic cultivation of D. subspicatus in sugarcane vinasse aiming the biomass production. The results pointed that pH and aeration had low influence in the cultivation, and the ideal batch time is near 9 hours, lowering the effects of bacterial contamination. The physicalchemical treatment was able to remove COD at the maximum of 40% using calcium hydroxide and 60% using aluminum sulfate. The optimization of the process conditions raised the lipidic productivity from 69 to 244,8 mg.L-1.day-1, suggesting the viability of the heterotrophic cultivation of D. subspicatus in vinasse.
O trabalho do agente comunitário de saúde na estratégia saúde da família: encontros e desencontros de uma prática em São Carlos/SP
(Universidade Federal de São Carlos, 2014-07-18)
Vieira, Kátia Cristina dos Santos
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Ogata, Márcia Niituma
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https://lattes.cnpq.br/3274294833403570
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https://lattes.cnpq.br/2220493766193400
This is a descriptive study with qualitative approach, more specifically a case study. It aims to analyze the work of Community Health Agent (ACS), from the perspective of health user and ACS itself, identifying the activities undertaken by these actors, perceptions of ACSs about his role on the team for the individual and collective care assitence, and the perceptions and expectations of users regarding the work of the ACS. The subjects were six ACSs from a unit of Family Health Program of city São Carlos, and four users of the health service and spokesman in the Local Health Council. Theoretical frameworks that supported this study and who were the object of theoretical study: family health, work and health care directives of the Brazilian Unified Health System (SUS).The research technique chosen for data collection was individual semi-structured interviews and data analysis used the technique of thematic analysis. The data collected with ACS and users were analyzed separately and yielded on the following categories: what is to be ACS: between the ideal and the real; organization of daily work of the ACS; demotivation and impotence in the face of adversity; lack of Permanent Education in Health: choking the work of ACS; who is the ACS to me; the real and the ideal work of ACS, and a user's perspective; the effort to strengthen the work of ACS. The results of this study allowed an approximation of the difficulties and easiness from everyday work of the ACS, sometimes demotivating elements, sometimes augmenting the practice of this worker. It was possible to identify the multifunctionality of ACS as one reason for the loss of identity from that worker before the population. As for users, the expectation that the ACS contributes to citizenship, advising people of their rights and duties, ie, not limited in their speeches to the technical work of the ACS was found, but contemplated the political and social dimension in the role of this worker. Research indicates that the change in the health production model depends not only on a worker-ACS- neither simple deployment of new family health teams. A joint effort of all health workers and a critical-reflective analysis of their own practices, reverberating effective change in health production and consolidation of SUS.
Determinação de Cd, Co, Cr, Cu, Ni e Pb em cosméticos infantis empregando técnicas espectroanalíticas
(Universidade Federal de São Carlos, 2014-07-18)
Augusto, Amanda dos Santos
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Pereira Filho, Edenir Rodrigues
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https://lattes.cnpq.br/3394181280355442
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https://lattes.cnpq.br/0641218916974686
In this study were developed two methods for sample preparation: one for children s eye shadow and another for chidren s lipstick. In the optimizing process, variables such as nitric acid concentration (2 or 7 mol L-1), sample mass (100 or 250 mg), heating time (1 or 3 hours) and concentration of Triton X-100 (5 or 25%) were investigated. The instrumental parameters of ICP OES were optimized in order to find a good working condition for the analytes determination. In the beginning it was performed a fractional factorial design 29- 5 (nine variables) and, after variables selection, a fine adjustment using Central Composite and Doehlert designs was made to study the most important variables (radio frequency power and nebulizer gas flow rate). In order to evaluate the regression models proposed, responses like LOQ and recovery for each analyte and in each view mode (radial and axial) were taken into consideration using desirability function. From the generated models it was possible to find the compromise condition with radio frequency power of 1200 W and a nebulizer gas flow rate of 0.825 L min-1. The methods developed for the preparation of the samples were applied to 22 samples of children cosmetics (14 eye shadows and 8 lipsticks). The analytes were determined using ICP OES (Cd, Co, Cr, Cu and Ni) and GF AAS (Pb). The majority of the concentrations obtained were lower than the international normatives, but the Pb values ranged from
O domínio prévio à definição das palavras: crítica à proposição como lugar do sentido a partir das Investigações Filosóficas de Wittgenstein
(Universidade Federal de São Carlos, 2014-07-18)
Zunino, Tatiane Boechat Abraham
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Ferraz Neto, Bento Prado de Almeida
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https://lattes.cnpq.br/0084436724293824
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https://lattes.cnpq.br/9466880793137887
This thesis seeks to examine the hypothesis that the meaning has not in its foundation the proposition and the words. That language does not inaugurate the truth in an enunciative joint, but in a practical and comprehensive operation. Thus, through Wittgenstein's Philosophical Investigations, we seeks to explain to what extent can we speak of an ambit of birthing of sense through the analysis of learning by the ostensive teaching of words, i.e., by means of some necessary conditions for the concept acquisition. To do so, we will expose some fundamental aspects of expression learning, both through teaching and verbal learning, namely, the notion of training (Abrichten) and all possible rationality which surrounds it, as well as the ostensive definition of words, trying to defend the position that training is the condition of possibility for the ostensive definition. Thus, it would be the first way of understanding, the birth of sense. After walking this path, it is possible to speak of two levels of access to sense. We try, therefore, to present a sense opening dimension through the linguistic practice in which an expression operates, so that the importance of the ostensive teaching of words is affirmed as the opening of a previous operative field that can enable the denomination. Such field implies that the expressions emerge with its meaning in the everyday praxis previously given, to then become an empirical language and bind to the facts of the world, so that the understanding of an expression assumes, in an essential way, the previous field of language and sense.
Secagem de sólidos porosos granulares
(Universidade Federal de São Carlos, 2014-07-18)
Perazzini, Hugo
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Freire, José Teixeira
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https://lattes.cnpq.br/2270677706718167
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https://lattes.cnpq.br/2676311547535414
In the present work, an experimental study about heat and mass transfer phenomena was carried out during drying of porous media when subjected to an upward flow of heated air. The cylindrical porous media consisted of non-consolidated particles of activated alumina of several diameters. The particulate system was initially characterized based on the achievement of its main physical, thermal and structural properties. The drying experiments consisted of obtaining sorption isotherms at different operational conditions and in determining moisture and temperature data versus time. The temperature profiles were obtained by thermocouples inserted in the porous body and the moisture content data by the gravimetrical method. The concept of time in series analysis was applied to determine the stationarity of the experimental data. The drying of the porous media was studied theoretically based on the context of the pseudo-homogeneous formulation, which led to the estimation of transport parameters of interest considering two situations: the presence of the external resistance to mass transfer and the interfacial equilibrium condition. The estimated transport coefficients were analyzed as constant or variable throughout the drying process. The diffusive mechanisms of mass transfer were estimated in order to identify the limiting one in drying. According to the results obtained, the vapor flux is controlled by liquid superficial diffusion into the particle. However, it was found that the effective moisture diffusivity is a harmonic mean of all the diffusive mechanisms, being the all type of moisture diffusivity of both particles and the porous medium important parameters in drying. The results showed that the drying of the porous medium studied is controlled by external resistance of heat and mass transfer. The pseudo-homogeneous formulation presented restrictions for the situation in which the interfacial equilibrium is admitted in the drying problem.
Conversão de bioetanol em acetato de etila: efeitos das propriedades eletrônicas do metal e estruturais dos suportes nos catalisadores Cu-Ag/ZrO2 e Cu/ZrO2/Al2O3
(Universidade Federal de São Carlos, 2014-07-18)
Freitas, Isabel Cristina de
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Marques, Clélia Mara de Paula
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https://lattes.cnpq.br/0451284088402660
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https://lattes.cnpq.br/9861067651401873
In both industry and academia the interest in biomass conversions into manufactured products has grown rapidly in recent years. Various products can be obtained from alcohol chemistry such as acetaldehyde, ethyl acetate, hydrogen, and others. Although copper-based catalysts are commonly used in the dehydrogenation of ethanol to acetaldehyde, recently Cu/ZrO2 catalysts have also revealed themselves to be highly active in the onepot transformation of ethanol into ethyl acetate. In this work, we studied the one-pot synthesis of ethyl acetate from ethanol by using two separate series of catalysts, Cu-Ag/ZrO2 and Cu/ZrO2/Al2O3. The characterization of the supports and catalysts were performed by N2 physisorption, X-ray diffraction, thermogravimetry, temperature programmed reduction, Fourier transformed infrared spectroscopy of the adsorbed CO (DRIFTS-CO), X-ray photoelectrons spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS). In the first part of this work, the study of the series of Cu-Ag/ZrO2 catalysts suggested that the Ag-Cu surface alloying alter the electronic properties in the catalysts surface, as verified by DRIFTS-CO. XPS measurements showed that increasing the Ag content in Cu-Ag/ZrO2 catalysts lead to a higher ratio Cu+/Cu0 on the surface. The predominance of Cu+ species on the surface led to catalysts with higher selectivity to acetaldehyde over ethyl acetate. The second part of this work studied the influences of Cu active phase dispersion on the ZrO2/Al2O3 support. Different Cu+/Cu0 species ratio, as verified by XPS, were obtained by varying the Cu content on ZrO2/Al2O3. Furthermore, the EXAFS results revealed that for the reduced catalyst increasing the Cu loading led to an enlargement in the size of the Cu0 particle. DRIFTS-CO showed that CO adsorption into these catalysts may be occurring on the surface of the copper xvi particles deposited on Al2O3 and/or ZrO2, since ZrO2 may not to be covering the whole Al2O3. Catalytic tests show that the products distribution in the one-pot ethanol conversion is affected by Cu0/Cu+ species ratio on the surface of the catalyst as well as the acid/base properties of the support. The increase of the Cu loading up to 30 wt. % favored the selectivity to ethyl acetate (67 % at 250 oC), due to an optimized Cu0/Cu+ species ratio on the surface of ZrO2/Al2O3 support. Theoretically, by increasing the relative Cu0 concentration, the formation of acyl species increases, which condenses with ethoxy species formed on Zrδ+ and Cu+ Lewis acid sites for the formation of ethyl acetate. Additionally, the Cu content of 30 wt. % provides greater surface coverage of the support ZrO2/Al2O3 suppressing the formation of acetaldehyde condensation products on the ZrO2 surface, such as crotonaldehyde; and further methyl ethyl ketone and diethyl ether formed in the alumina acid sites.
Canais de comercialização de orgânicos: desafios e alternativas de agricultores familiares do leste paulista
(Universidade Federal de São Carlos, 2014-07-21)
Oliveira, Priscila Silveira de
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Marjotta-Maistro, Marta Cristina
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https://lattes.cnpq.br/3987280258617095
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https://lattes.cnpq.br/6102996140263032
This paper aims to describe some market alternatives adopted by smallholders farmers on the distribution channels for organic in natura products. Therefore, besides the literature review on this matter, the methodology includes the collection of primary data based on semi-structured interviews with fourteen smallholders farmers. The interviewees are smallholders farmers from eastern side of Sao Paulo, geographically located between two river basins: Capivari-Piracicaba basin and Mogi Guacu. Farmers are found by snow ball method. It is showed that the distribution channels, so called short channels , are the mainly strategies used on family farming. The market fairs are the sell places which the farmers chose as the best one for their needs. The main reasons for that are the better prices they can get due to the absence of any middleman in the selling process and the closest approach to the consumers. The worst channel in their opinions is the supermarkets due to unfavorable contracts required. Those contracts include lower prices, assuming the products that were over (not sold) and bonus profits to the supermarkets on special occasion to name some of them. This study showed that is important to implement actions to enable organic agriculture and commercialization management, logistics and accounting in the distribution process of these products. Considering this, formal or informal associations for production or commercialization have showed to be more efficient and safe compared to individual work, especially as a strategy for production diversification, constancy in offer and searching for new markets.
Químio-, régio- e estereosseletividades das reações de Diels-Alder de para-benzoquinonas: um estudo teórico
(Universidade Federal de São Carlos, 2014-07-23)
Servilha, Bruno Moraes
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Brocksom, Timothy John
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https://lattes.cnpq.br/7055452150201902
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https://lattes.cnpq.br/1729692550121820
In this work, some computational theoretical studies on the reactivity of para-benzoquinones and their derivatives in Diels-Alder reactions were proposed These studies were done in order to compliment the corresponding experimental studies ongoing in our laboratory. The Diels-Alder reactions between carbomethoxy-parabenzoquinones 16, 17 e 19 and cyclopentadiene furnished type-A cycloadducts whereas in the corresponding reaction of 18, the B-type cycloadduct was formed. The regiosselectivity of these reactions were rationalized by the comparison of the corresponding transition state energies and the relative stability of the cycloadducts. The presence of a methyl group adjacent to group carbomethoxy in the dienophiles 18 and 19 inhibits the conjugation of these group with the ring systen, and the regiosselectivity on these reactions, at first sight, is not predictable. (CONTINUE)...
Anelasticidade em titânio, tântalo e na liga Ti-40Ta
(Universidade Federal de São Carlos, 2014-07-24)
Patricio, Marco Antonio Tito
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Florêncio, Odila
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https://lattes.cnpq.br/2881221058860977
The growing demand for increasingly resistant and biocompatible with the human body implantable materials, has led to an increase in demand for new metallic biomaterials. Some materials, such as titanium and its alloys, especially the Ti-6Al-4V, are widely used in the manufacture of orthopedic implants due to their excellent biocompatibility, high corrosion resistance and low density. However, the characteristics of these materials are not considered optimal, mainly because they have a high value of the elastic modulus when compared to the human bone. Include, that in the last decade studies have revealed diseases associated with elements such as Al and V, present in the alloy Ti-6Al-4V. Thus, it have looked for alternatives to the alloys used as biomaterials, still having one common element titanium, but having no toxic elements such as 𝛽 type titanium alloys, formed by non-toxic elements such as Nb, Ta, Zr, Mo and Sn has shown that lower values of modulus, greater fatigue resistance and corrosion resistance, exhibiting excellent biocompatibility. Accordingly, the alloys formed by Ti-Ta become promising candidates as biomaterials, since it has been observed that the content of Ta affects the value of the elastic modulus. For some compositions of this alloy, lower modulus values of this alloys that are currently used in biomedical applications were observed. However, the alloys formed by Ti-Ta still have properties that have been little studied. Thereby, the objectives of this master s project consist in getting the alloy Ti-40Ta and its characterization by means of the technique of mechanical spectroscopy, as of its elements that compose the alloy. The technique of mechanical spectroscopy to be non-destructive, it is widely used for providing the anelastic spectrum (oscillation frequency and internal friction as a function of temperature) is considered sensitive to phase transitions and dynamic processes, which are essential for understanding the structural changes occurring in these materials. This study was determined the dynamic elastic modulus for the pure Ti and Ta elements, and the Ti-40Ta through flexural vibrations. The elastic modulus found for the alloy at room temperature was (71 ± 5) GPa, which is in accordance with results available in the literature. The value of modulus of the alloy is lower when compared to the commercial biomedical alloys and is closer to that of human bone, which makes the alloy Ti-40Ta a potential candidate to be used in biomedical applications.
Desenvolvimento de sensores eletroquímicos utilizando nanomateriais para a determinação de espécies de interesse farmacêutico e ambiental
(Universidade Federal de São Carlos, 2014-07-25)
Figueiredo Filho, Luiz Carlos Soares de
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Fatibello Filho, Orlando
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https://lattes.cnpq.br/9859737944357808
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https://lattes.cnpq.br/3210207943263219
In this work the development of new sensors using nanomaterials is decribed. Glassy carbon electrode modified with gold nanoparticles and functionalized multi-walled carbon nanotubes within a dihexadecyl phosphate film was fabricated and applied to determine diquat in natural water samples by square wave voltammetry (SWV). The analytical curve was linear in the diquat concentration range from 3.1 × 10−8 to 3.0 × 10−6 mol L−1 with a limit of detection (3 blank/slope of analytical curve) of 1.4 × 10−8 mol L−1. The performance of this electrode was compared with a commercially screen printed electrode from dropsens. The determination of linuron in natural water samples and commercial products was successfully performed using the boron doped diamond with good linear range, repeatability, sensitivity and stability. Moreover, the electrode had the analytical characteristics compared with the same electrode modified with platinum nanoparticles. A glassy carbon electrode with dihexadecyl phosphate film containing platinum nanoparticles was developed to determine linuron and carbendazim in natural waters, orange juice and commercial products by pulse diferential voltammetry (DPV) and square wave voltammetry (SWV) techniques. The detection limits obtained were 6.1 × 10−10 and 1.5 × 10−9 mol L−1 for linuron and carbendazim using SWV, respectively, and the obtained results were in agreement at a 95% confidence level with those results obtained using a high performance liquid chromatography method. Glassy carbon electrode modified with nickel oxide nanoparticles and functionalized multi-walled carbon nanotubes within a dihexadecyl phosphate film was fabricated and applied to the simultaneous determination of dopamine and epinephrine by DPV. The analytical curve obtained shown a linear range from 7.0 × 10−8 to 4.8 × 10−6 and 3.0 × 10−7 to 9.5 × 10−6 mol L−1 for dopamine and epinephrine, respectively. Both analytes were determined in three different synthetic samples of biological fluids (lung fluid, cerebrospinal fluid and human serum) with an acceptable relative standard deviation for the addition and recovery test. Graphene and graphite paste electrodes were also investigated in this thesis. Initially, graphene and graphite were characterized morphologically (RAMAN and XPS), as the obtained pastes. Moreover, the proposed paste electrodes were characterized electrochemically through well-known electrochemical probes as hexacyanoferrate (II) potassium, hexamine ruthenium chloride (III) and hexacloroiridiate (III) sodium. After this study, analytical curves for ascorbic and uric acids were built. It was observed that no significant analytical advantages were obtained when graphite was replaced by graphene in the pastes. The electrochemical of graphene and reticulated vitreous carbon three-dimensional electrodes was first explored in this work. It was observed that due to the hydrophobic nature of the graphene three-dimensional electrode, its application is not favorable in aqueous solutions. Furthermore, this material showed good electrochemical characteristics using ionic liquids as supporting electrolyte, better HET and higher current to electrochemical probes hexacyanoferrate (II) potassium, hexamine ruthenium (III) chloride, ferrocene and N,N,N',N'-tetramethyl-p-phenylenediamine compared with the three-dimensional reticulated vitreous carbon electrode.
Conteúdos digitais para o tema ondulatória na proposta curricular do Estado de São Paulo
(Universidade Federal de São Carlos, 2014-07-25)
Magalhães, Arthur Alexandre
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Arantes, Alessandra Riposati
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https://lattes.cnpq.br/6742903299047989
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https://lattes.cnpq.br/4217678767890330
This work proposes digital content for the Waves theme which can be inserted into the curriculum of the State of São Paulo. Technologies are part of the daily lives of students, and can be used as motivational tools in the teaching-learning process. Digital content consists of learning objects, such as videos, audios and simulations, accompanied by activities that provide an active student participation in the teachinglearning process. Activities were inspired by research methodology and have different levels of freedom, i.e. varying degrees of teacher intervention. We conclude that the activities with greater student autonomy lead to a more meaningful concept learning. It is noteworthy that, in addition to the positive result, this work has produced a considerable change in my teaching practice as I started to develop activities with investigative approach, in which the student carries out the process of knowledge construction.
Nano-microencapsulados de extrato de Azadirachta indica usando ligninas do bagaço de cana-de-açúcar: estabilidade e eficácia contra insetos pragas
(Universidade Federal de São Carlos, 2014-07-25)
Costa, Eveline Soares
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Forim, Moacir Rossi
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https://lattes.cnpq.br/1234565160573730
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https://lattes.cnpq.br/9126084206992314
The present work aimed the development of a model bioinsecticide for pest insect control using microencapsulated botanical extracts of Azadirachta indica (neem), and natural polymer of lignins, witch were extracted from sugarcane bagasse. Several different extraction methods and chemical modifications were carried out on lignin in order to evaluate yield, cost, environmental advantages and biological efficacy. Among the proposed chemical modifications the main reactions were oxidation and acetylation. Techniques used for biopolymer characterization were FITR, 1H NMR, MALDI-TOF and SEM. Chemometric tools on NMR analyses aided on lignin differentiation according to their groups: oxidized, acetylated and naturals. Lignins were used in microencapsulation processes of extracts and fractions of the natural insecticide, A. indica L. Juss, by using Spray-Drying methods. The obtained products were subjected to thermal and photochemical degradation assays. The formulation promoted stability gains of approximately 40% for the formulated botanical extract. Use of commercial thermal and photochemical protectors were also investigated where it was observed that lignin was more efficient than traditional commercial photostabilizers protectors, showing that there is no need for adding synthetic protectors on microencapsulation process, and consequently, they are not needed on the final product. Microencapsulation was done through process known as Nanoemulsion/Solvent Displacement developed by the workgroup. In this process, botanical material was firstly nanoemulsioned, coated by a biopolymeric film in order to promote nanocapsules, and dried using Spray-Dryer generating micrometric clusters. All formulated material was subjected to biological assays to Spodoptera frugiperda, Diabrotica speciosa, Diatraea saccharalis e Anticarsia gemmatalis. Data obtained on biological testes shows that formulations that were prepared with neem and lignin were as active as non-formulated botanical extract on pest insects.
Avaliação das características mecânicas de compósitos de cimento Portland reforçados com fibras de polipropileno aditivadas com modificadores de superfície
(Universidade Federal de São Carlos, 2014-07-25)
Esposto, Ricardo Francisco
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Morelli, Márcio Raymundo
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https://lattes.cnpq.br/0172837599844991
;
https://lattes.cnpq.br/7978232406039488
The application of polymeric fibers as reinforcement in cement based composites is a highly developed technology in various applications in construction. The use of polypropylene fibers have been widely used, but with some technological limitations, mainly because of them present low interaction with the cement matrix when compared with other polymeric fibers. For this work, we sought to evaluate polypropylene fibers doped with surface modifiers, with emphasis on mechanical and microstructural characteristics of composites. Different amounts of fiber with and without surface modifying additives in matrices of Portland cement mortar after 35 days of age were evaluated. The physic-chemical interactions of the fiber with the matrix were evaluated by pullout tests and through reviews of scanning electron microscopy. Some specimens were subjected to accelerated aging tests and these samples were analyzed by electron microscopy to observe the behavior of the interaction of the fiber with the additive, but also for assessing the behavior of the fiber with the matrix after exposure to aging. The results obtained by the mechanical resistance measures uniaxial compression and scanning electron microscopy showed that a mechanical reinforcement occurs independent of incorporation of additives in fiber to additions of 1.2 kg/m3. On the other hand, the surface-treated fiber exhibited higher degree of adhesion to the matrix.
Uso de ferramentas tecnológicas no ensino de física para o ensino médio: modelagem matemática a partir do software Modellus
(Universidade Federal de São Carlos, 2014-07-25)
Barsotti, Daniela Cristina
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Garcia, Ducinei
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https://lattes.cnpq.br/5236758856687873
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https://lattes.cnpq.br/8857372188018044
This work presents a case study on the teaching and learning of Physics concepts using mathematical modeling and technological tools, with software Modellus 4.01 as the main resource. Modellus 4.01 was selected due to its ability to provide a user-friendly platform for developing animated simulations from user-defined mathematical models, in addition to windows that can display graphs and tables dynamically. The main objective of this work is to propose an answer to the question: Is it worthwhile to use a computational tool with mathematical modeling to enhance student s learning results in secondary education? After all, much has been presumed about using computers to improve Brazil s overall performance in basic education, but there are very few formal studies on their actual utilization, especially at a complex level like the simulations from mathematical models developed by the students themselves. A sequence of activities for the modeling of kinematics concepts is proposed and discussed. While considering the steps of such sequence and their application with 9th-grade students in computer-equipped facilities, this work also presents and analyses the results of a diagnostic assessment of students theoretical knowledge; their acceptance of the Modellus software; the URM and UVRM simulations they developed; and the concepts they gathered from the work with modeling and computational tools. It is therefore possible to reflect upon the effectiveness of this methodology towards a more meaningful learning of the concepts involved, as well as the difficulties arising from the use of technological tools in the school environment. The outcomes from sharing the products and investigations of this work with other teachers, whether in specific projects like the Observatório da Educação (The Observatory of Education - Obeduc Capes-UFSCar) or in academic networking events are also discussed. In general terms, results show that the application of activities in the suggested order may be an important support to the motivation of students and to a meaningful learning of the Physics contents pertaining to the 9th grade program.