Browsing by Issue Date, starting with "2008-03-13"

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Caracterização elétrica e magnética de Fe granular embebido em matriz de ZnSe
(Universidade Federal de São Carlos, 2008-03-13)
Muniz, Pedro Schio de Noronha
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Oliveira, Adilson Jesus Aparecido de
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https://lattes.cnpq.br/4640148190073166
;
https://lattes.cnpq.br/4464937635959170
Electric and magnetic properties of nanoscopic clusters of iron immersed in Zinc Selenide were studied in this work. The system presents superparamagnetic behavior with a weak thermally activate ferromagnetic interaction. Small tunnel magnetoresistence was observed in room temperature (approximately 1% with fields of 30 kOe) and its behavior was observed as a function of temperature and bias. This work demonstrate that a despite of excellent macroscopic and microscopic properties of Fe/ZnSe/Fe epitaxial heterostructures the experimental observation shows small values of tunnel magnetoristance in room temperature. This results shows that the application of this materials in spintronics devices is limited.
Estudo dos processos de eletrodeposição de filmes finos de Se, ZnSe e PbS
(Universidade Federal de São Carlos, 2008-03-13)
Fernandes, Valéria Cristina
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Mascaro, Lucia Helena
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https://lattes.cnpq.br/9130022476352844
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https://lattes.cnpq.br/7987385835577071
This work describes studies on the underpotential deposition (UPD) of selenium, zinc, as well for Zn/Se systems deposited on polycrystalline Pt electrodes in acid solutions. The effects of Zn presence in the Se dissolution process were also investigated in the UPD and bulk potential range, 0.6 and 0.03 V respectively. The measurements were carried out using cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). Furthermore Lead sulfide (PbS) multilayers were grown on a single crystal Ag(111) substrate by Electrochemical Atomic Layer Epitaxy (ECALE) method. For Zn UPD in sulfuric acid, two different processes were observed, which are attributed to the dissolution of submonolayer of Znads and H-atoms adsorbed on the electrode surface. For Se UPD was observed that hydrogen desorption were completely inhibited indicating that Se film recovered the Pt surface. The deposition of UPD Se in perchloric acid solution showed the transference of 4 electrons with 1.4 and 1.12 active sites of Pt occupied by 1 Se ad-atom in the UPD and bulk potential range, respectively. In the evaluation of the Se monolayers dissolution process formed at 0.03 V during 2000 s a process not mentioned in the literature it was observed which was evaluated by the technique MECQ. The experimental results obtained by this technique allowed to end that the dissolution process occurred by two stages, and the first involved the participation of 6e-. The dissolution mechanism with 6e- happens with the participation of water in the dissolution process of Se, leading to the formation of an oxygenated selenium compound which in next step undergo slow oxidation and is dissolved as soluble Se(VI) species. Then the total dissolution process of Se occurs in a six-electron transfer reaction. For Se deposition in the Zn presence the dissolution charges associated with Se UPD increase, indicating that the presence of Zn favors the deposition of UPD Se. In the case of PbS multilayers on Ag (111) the voltammetric analysis of the first PbUPD and SUPD peaks indicates a mechanism of two-dimensional growth, which is consistent with epitaxial growth. Electrochemical stripping measurements indicate that the amount of Pb and S deposited in a given number of cycles is a function of the number of cycles employed, again suggesting a layer-by-layer growth. This result indicates that the amount of Pb and S in these films corresponds to the stoichiometric 1:1 ratio, indicating the formation of a compound.
Programação de ensino de leitura e escrita para crianças com deficiência mental
(Universidade Federal de São Carlos, 2008-03-13)
Freitas, Maria Clara de
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Rose, Julio Cesar Coelho de
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https://lattes.cnpq.br/3386857761295187
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https://lattes.cnpq.br/6993887072345221
The importance of reading and spelling for citizens is a significant issue. However, repeatedly the school system shows failures in teaching these repertoires. When children with mental retardation are inserted in the regular classroom, the problems increase. Teachers don t know how to teach them academic skills, therefore obscuring their potential and prejudicing their social inclusion. Moreover, studies in equivalence of stimulus have systematically demonstrated the applicability of procedures based on this paradigm for individuals with mental retardation, as well as the effectiveness of similar methodologies applied to the teaching of rudimentary reading and spelling skills to other populations, such as preschool students and children with developmental disorders. Therefore, the objectives of this study were: a. to investigate the necessary conditions for the teaching of children with mental deficiency using a procedure designed to of teaching reading and spelling, and b. to redesign the software that contains this procedure in order to achieve results for the children with mental retardation compatible with the ones obtained by the application of this same software to children with school failures. A multiple baseline design with a mobile criterion, has been used, focusing the analysis on the three participants performance when exposed to the modifications implemented by the three consecutive procedures. The results indicated small profits for Procedure 1, when only formal modifications in the software were made, such as exchange of stimuli (words and pictures) and exhibition of the font in capital letters. As the second procedure introduced more structural modifications, as blocked-trial trainings and auditory-visual trials with critical differences between the words, the results showed great success for all the reading and spelling skills tested. The last procedure made refinements in the program, and equally reached success with shorter trainings and bigger words. As a conclusion of the work, success was reached in the adaptation and application of the teaching program: the children with mental retardation showed results of reading and spelling compatible with the results the pupils with learning difficulties had shown in previous studies. Furthermore, it was also possible to say that the data obtained had contributed to understand a little more how and how much this students learn, and how this learning can be guaranteed and optimized using procedures based on matching to sample, constructed response matching to sample and exclusion.
Do conhecimento tradicional ao princípio ativo: dilemas sociais da atividade de pesquisa etnofarmacológica
(Universidade Federal de São Carlos, 2008-03-13)
Almeida, Marcelo Fetz de
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Vargas, Marcelo Coutinho
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https://lattes.cnpq.br/3936124976880088
The Research and Development (R&D) in ethnopharmacology and etnobiology fields, guided by the therapeutic information obtained with local communities and indigenous people, holders of traditional knowledge, produces social conflicts and social disputes. Firstly, it is a paradoxical scientific activity since the modern scientific discovery in ethnopharmacology is produced by a non-scientific knowledge. This controversial research strategy intends to produce a socially legitimized knowledge through a process of epistemic standardization. Secondly, although the use of traditional knowledge is a typical activity, to access it and to use it requires the signature of a contract for the equitable sharing of benefits as well as the signature of a term of prior consent access. These two juridical requirements are at the same time a new ethical parameter in scientific research and a barrier to the autonomy of the scientific field. Therefore, through the politic action scientists and researches seeks new social strategies to recovery the autonomy of the scientific field in ethnopharmacology and ethnobiology areas. Thus, this sociological research analyzes the internal conflicts between scientists in the scientific field through the examination of the social controversies in the use of two distinct research models, the vertical and the horizontal research models, as well as the examination of the external social disputes of the scientific activity, specially the politic action of scientists concerning to the autonomy question. In this research, the question of access, use and equitable sharing of benefits in R&D processes emerges as an interesting strategy used by scientists to legitimate the appropriation of the traditional knowledge. As non-knowledge, the traditional knowledge is transformed by the modern commercial science in generic information without significance. At the same time, this traditional generic information would be liable to be manipulated and appropriated by pharmaceutical multinationals trough the application of intellectual property rights. Finally, the appropriation of the traditional communities claim intends to legitimate socially the controversial scientific activity of ethnopharmacologists, ethnobiologists and pharmaceutical industries.
Quantificação de mRNA de genes relacionados à resposta imune em bovinos infectados com endoparasitos do gênero Haemonchus spp
(Universidade Federal de São Carlos, 2008-03-14)
Ibelli, Adriana Mércia Guaratini
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Regitano, Luciana Correia de Almeida
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https://lattes.cnpq.br/4729789236742545
Brazilian livestock production presents great impact for the national agriculture, possessing the largest bovine commercial herd of the world. However, the productivity is low and gastrintestinal diseases caused by Haemonchus spp are one of the major constraints to the production. It is known that those parasites are responsible for many immunological responses in the host. Cytokine polarization Th1/Th2 has been studied to understand the infections caused by nematodes. However, the studies that try to understand immune response of cattle with Haemonchus spp are still scarce. The goal of this work was to verify differences in the mRNA abundance of genes involved in immune response of calves of Nelore breed (Bos indicus) submitted to the first infection with Haemonchus spp, relating these differences to patterns of cellular infiltrate. Genes were evaluated by real time PCR and relative quantification was made by the software Relative Expression Software Tool. Results showed up-regulation of the interleukins IL-4 (p≤0.05) and IL- 13 (p≤0.05) in the lymph node of challenged animals. No significant differences (p > 0.05) were found in mRNA abundance for the genes analyzed in abomasum. There were no significant differences for mast cells and eosinophil counts in abomasal tissue among analyzed groups. From the results, it can be concluded that for the short infection time, there was increased polarization of Th2 in lymph node, but it was not seen in abomasal tissue.
Efeitos dos exercícios de aquecimento e alongamento na flexibilidade de sujeitos idosos
(Universidade Federal de São Carlos, 2008-03-14)
Ferreira, José Jamacy de Almeida
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Salvini, Tânia de Fátima
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https://lattes.cnpq.br/7942403520160630
Influência da orientação corporal no movimento de cabeça em bebês nos quatro primeiros meses de idade
(Universidade Federal de São Carlos, 2008-03-14)
Lima, Carolina Daniel de
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Tudella, Eloisa
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https://lattes.cnpq.br/3207258034860219
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https://lattes.cnpq.br/4144337339534625
Efeito da temperatura na otimização da produção de glicoproteína do vírus da raiva em cultivos em suspensão de células recombinantes de Drosophila melanogaster S2
(Universidade Federal de São Carlos, 2008-03-14)
Rossi, Nickeli
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Suazo, Cláudio Alberto Torres
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https://lattes.cnpq.br/6372015269730595
The increment of the expression of complex correctly processed recombinant proteins, like the ones produced by animal cells, is essential for the development of an efficient large scale bioprocess. The manipulation of culture conditions plays a very important role in the controlled and optimized expression of these proteins in bioreactors. The response of mammalian and insect cells to temperature effect has been studied by several researchers as a potential strategy to enhance production of recombinant proteins. The present study evaluated the influence of the temperature in the culture of recombinant Drosophila melanogaster S2 cells in Sf-900 II medium supplemented with aminoacids with the aim of enhancing the production of the rabies virus glycoprotein (RVGP). The cultures were carried out in Schott flasks (in shaker) as well as in a bubble-free stirred tank bioreactor. Five temperatures were tested in Schott flasks cultures: 16, 20, 24, 28 and 34ºC. The results obtained in cultures at those temperatures in terms of maximum specific growth rate (µmax) and maximum RVGP concentration (CGPV max) were, respectively: 0.009, 0.020, 0.039, 0.036 and 0.022 h-1, and 0.075, 2.973, 0.480, 1.404 and 0.013 mg.mL-1. The best temperature for RVGP production (20oC) was chosen to be evaluated in the bioreactor operated in batch and feed-batch mode, keeping 28oC as control. The results of µmax and CGPV max in batch mode were: 0,061 h-1 and 0,149 mg.mL-1 at 28oC and 0,027 h-1 and 0.354 mg.mL-1 at 20oC. A batch experiment with stepwise temperature decrease from 20ºC to 16ºC presented a µmax ranging from 0.024 to 0.012 h-1 and a final CGPV max of 0.567 mg.mL-1. On the other hand, at 20ºC in feed-batch mode, µmax was 0.024 h-1 and CGPV max 1.155 mg.mL-1. The larger production of RVGP observed in Schott flasks can be a consequence of a more favorable condition for the expression of the protein at low values of dissolved oxygen concentrations that are seen in flasks but not in controlled bioreactor cultures at 50% DO. Overall, these results show an increase of recombinant protein expression at lower temperatures, especially when µmax is kept fairly low. The largest production of RVGP was obtained in the culture at 20°C in Schott flask when CGPV max was 2.973 mg.mL-1, while the production obtained at the control temperature of 28ºC was only of 1.404 mg.mL-1. Thus, the use of reduced culture temperatures, around 20°C, seems to be the best strategy for the optimization of RVGP production.
Estudo do comportamento da deposição das partículas de diferentes meios filtrantes
(Universidade Federal de São Carlos, 2008-03-17)
Tanabe, Eduardo Hiromitsu
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Aguiar, Mônica Lopes
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https://lattes.cnpq.br/0431688649128529
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https://lattes.cnpq.br/9778700143605069
Many studies related to bag filters have focused on minimizing the amount of energy used in the process. Seeking longer filtration cycles, lower frequency of cleaning cycles and a longer filter life, such studies search for fabrics which present easy cake removal and the least loss of residual pressure drop. There are many studies related to the formation and removal of filtration cakes but little is known about the behavior of particles deposited on the inside of the filter and what influence these particles have on the performance of filters. For this reason, the objective of this study was to investigate particle deposition behavior and particulate materials on the interior of different filter materials after the cleaning process and to evaluate the impact of these particles on the regeneration of the fabric under microscopic examination. Particulate materials utilized were phosphatic rock and manioc starch with filter mediums of treated polyester, untreated polyester, polypropylene and acrylic. The filter trials were carried out at a filtration velocity of 0.10 m/s. The cake removal process was done by reverse airflow at a cleaning velocity of 0.12 m/s. The maximum pressure drop permitted in the filtration trials was 980 Pa. Utilizing phosphatic rock and acrylic, polypropylene and treated polyester, the depth of particle deposition on the polypropylene fabric was less deep in relation to the other two fabrics studied. The residual pressure drop of this fabric was greater, demonstrating that the accumulation of particulate material in this filter medium provided a greater resistance to flow, due to the smaller spacing encountered between the fibers of this fabric and consequent closing of pores. For the manioc starch particles on treated and untreated polyester, a greater depth of particle deposition was observed on the untreated polyester, showing that the absence of treatment allowed the fabric to obtain greater particle deposition on the interior of the filter medium, which increased the resistance to flow and the system residual pressure drop. This shows that the characteristics of the filter medium and the particulate material both exercise an influence on the depth of particle deposition and on residual pressure drop in the system. Thus, the best performance encountered utilizing particulate materials of phosphatic rock or manioc starch under the experimental conditions, was with the treated polyester. A study on the effects of the operational variables on particle deposition depth was also conducted, utilizing a three level experimental plan, 3k, to evaluate the effect of the variables, filtration velocity (Vf) and filtration time (tf). Results showed that both these variables presented an influence on the response variable, but the variable that produced the greatest significant effect was the filtration velocity. The utilization of lower values of velocity and lower values of filtration times is suggested to achieve lower levels of particle deposition depth, because the increase in particle deposition on the interior of the filter obstructs the air flow through the filter, thus slowing the cleaning process and provoking an increase in residual pressure drop.
A lucidez imperfeita: ensaio sobre Freud como escritor
(Universidade Federal de São Carlos, 2008-03-17)
Carone, André Medina
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Santos, Paulo Roberto Licht dos
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https://lattes.cnpq.br/1681044854219924
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https://lattes.cnpq.br/5392166032777488
Uma investigação sobre paradigmas tecnológicos e abordagens pedagógicas dos tutores inteligentes nos sistemas de ensino-aprendizagem
(Universidade Federal de São Carlos, 2008-03-17)
Monaco, Fabíola Maria
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Mizukami, Maria da Graça Nicoletti
This research work has as its starting point the conjecture posed by Oliveira regarding a possible technicist reflux yielded by the dissemination of new information and communication technologies (ICTs) over varying extents (political, economical, scientific etc.), highlighting its incidence on the implementation of its resources in the domain of the methods and techniques of education. In this context, focusing on the Intelligent Tutoring Systems (ITS) as a representative instance of such educational technologies (with novel paradigms with respect to other media such as data extraction and computation and information inference), this investigation aims at assessing and explaining, through the pedagogical perspective, the possible occurrence of approximations to the technicism. The methodology relies on the in-depth study of the ITS based on the pedagogical paradigms which ground the focused educational technology, being the method of analysis that of established models and processes of the System Engineering field, in which ITS are effectively developed as artifacts. The results identify and explain non-intentional technicists approximations that are not inherent neither to the conception nor to the implementation, but to an intermediary phase of the process corresponding to the system design. In addition, some considerations are drawn on the difficulties and hindrances found in the disciplinary study of interfacing technologies
Características físicas e químicas da água e características reprodutivas do Curimbatá (Prochilodus lineatus Valenciennes, 1836) no rio Mogi-Guaçu, SP, Brasil
(Universidade Federal de São Carlos, 2008-03-18)
Ramos, Roseli Ormanezi
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Peret, Alberto Carvalho
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https://lattes.cnpq.br/0995579236780271
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https://lattes.cnpq.br/7520453139124587
Evolução de variáveis fisiológicas e análise de eficiência (DEA) de mulheres senescentes submetidas a um programa prolongado de atividades físicas
(Universidade Federal de São Carlos, 2008-03-18)
Borges, Camila Fernanda
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Rebelatto, José Rubens
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https://lattes.cnpq.br/1684247449456330
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https://lattes.cnpq.br/9017953752844145
OBJECTIVE: To identify the evolution of the physiologic variable corporal mass index , muscular force , flexibility , balance and aerobic conditioning (VO2 max) of elderly women submitted to a long physical activity program and to verify the women s efficiency during the program, through the Data envelopment Analysis (DEA). METHOD: 120 women participated, with ages between 50 and 79, average age 60,87 + 7,81 years old, not institutionalized and resident in Sao Carlos. Eight evaluations were accomplished during two years, being one before the beginning of the program of physical activities and the other ones, in intervals of approximately three months. In all the evaluations the following variables were measured: blood pressure, heart frequency, weigh and height (for the calculation of the Index of corporal mass) muscular forces, flexibility, balance (static and dynamic) and response to physical effort (VO2 max). Each section of physical activity involved prolongation mioface passive exercises of the main muscular groups, exercises of aerobic resistance, power and resistance, coordination activities, agility and flexibility, breathing exercises, relaxation and hydratation in two moments of the session. The data regarding the evolution of the physiologic variables were analyzed through the method of Bonferroni and the Method of Friedman, respecting a significance level of α = 0,05. With reference to the analyses of the efficiency of the participants, were considered the individuals that participated of the eight evaluations and had frequency superior to 74%, but for the analyses of the DEA, were used the third, the fifth and seventh evaluation, since the control of the senior s attendance was concluded by the teachers every six months. It is interesting to note that for the general analysis of the program spreadsheets with the total number of sessions were built with the total number of sessions accomplished during eighteen months, total time of each exercise and the attendance of the elderly women during the whole program. RESULT: There was an improvement in all the variables studied (IMC, force, flexibility, balance and VO2 max), but it was statistically significant in the variables flexibility (p = 0,000), balance (p = 0,000) and VO2 max (p = 0,0004). With reference to the efficiency, it was possible to observe that most of the women were efficient (they reached an efficiency level above 60%) along the program of exercises and also in all the evaluation studied (third, fifth and seventh evaluations). Besides, it was observed the necessity of alterations in the program of physical activity, so that, a portion still larger reaches higher efficiency levels. CONCLUSION: Through the analyses of the results it was possible to verify that a long physical activity program is able to alter positively the physiologic variables of the elderly women and that they were efficient along this program of exercises.
Modificação do Poli(hidroxibutirato) PHB com nucleantes e com o copolímero (etileno-co-acetato de vinila) - EVA
(Universidade Federal de São Carlos, 2008-03-19)
Falcone, Daniele Maria Bruno
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Agnelli, José Augusto Marcondes
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https://lattes.cnpq.br/7592090152400440
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https://lattes.cnpq.br/8438856690765294
In this work, we sought to modify PHB, processing it in the melted state, and to evaluate the effect of the modifications on its mechanical properties and biodegradation characteristics. The following systems were therefore studied: a PHB/EVA blend, in a 90/10 ratio, with an ethylene-co-vinyl acetate copolymer containing 28% of VA; a PHB and PHB/EVA blend with 1% of Boron Nitride (BN) nucleant; a PHB and PHB/EVA blend with 0,35% of HPN nucleant ( Hyperform Nucleant ); and a PHB/EVA blend with 5% of Elvaloy PTW, which was used as a compatibilizer. These systems were characterized by thermal, mechanical, morphological and biodegradation analyses using the following techniques: Melt Flow Index (MFI), Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Dynamic Mechanical Thermal Analysis (DMTA), Size Exclusion Chromatography (SEC), Tensile Mechanical and Izod Impact (notched) Tests, Wide-Angle X-ray Diffraction (WAXD), Scanning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). The biodegradability test involved burying the samples in a suitable compost for 60, 120 and 180 days. The DCS analysis indicated that Boron Nitride was an effective nucleating agent for the PHB. However, the HPN did not act as a nucleant on this polymer, but instead, induced degradation of the PHB upon heating, as indicated by MFI, DSC and TG. Moreover, the addition of BN or even EVA did not improve the mechanical properties of PHB, and Elvaloy PTW did not act as a compatibilizing agent for the PHB/EVA blend. The HPN was found to interact antagonically with the PHB, which displayed extremely low impact strength values and widely dispersed results. The SEM and AFM analyses revealed poor distribution and inadequate dispersion of EVA in the PHB matrix. In addition, the AFM technique indicated that the PHB topography displayed the presence of pores, which undoubtedly, combined with the other factors, hindered its modification. Biodegradation was found to be strongly composition-dependent, since the addition of 10% of EVA to the PHB significantly accelerated the degradation of the PHB in this blend. In other words, the PHB probably exhibited disordered chain packing in the proximities of the EVA, facilitating the process of biodegradation by microorganisms. Hence, this study demonstrated the difficulty of modifying PHB, since it involves a variety of factors, as well as the possibility of developing PHB-based materials that biodegrade more or less rapidly according to the needs of a specific application.
Processos de participação para o controle social em comissões locais de saúde: educar-se no cotidiano
(Universidade Federal de São Carlos, 2008-03-19)
Barbosa, Ana Maria Giusti
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Oliveira, Maria Waldenez de
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https://lattes.cnpq.br/3404769527869004
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https://lattes.cnpq.br/0387355124707530
In the set of the changes occurred in the Brazilian society since the promulgation of the Federal Constitution in 1988, lies the institutionalization of the society means of participation for purposes of social control on the public policies. Among these means are the Management Councils. In the health area, we can find Health Councils in national, state, city and local levels. Having the Knowledge that the Health Local Commissions, local modality of the Councils, are spaces where the social control and participation social practice occurs, and educative processes are broken out, built and configured according to circumstances and particularities of each of them, the following research question was made: "Which are the educative processes related to the participation exercise and social control experienced, generated, built and unchained in the Local Health Commissions?". This research had as purpose to understand the Health Local Commissions in the city of Piracicaba in São Paulo state regarding the educative processes experienced by its participants. The theoretical referential adopted was the Pedagogia Sócio-Cultural by Paulo Freire and Theory of quotidian by Michel Maffesoli. Methodologically, it consisted on a study of qualitative character based on contributions of the phenomenological theory for insertion in field and data analysis. The field research was made in the period of 2004 to 2007, comprising 14 Health Local Commissions of Piracicaba. The procedures used for data collection were the observations of the commissions functioning and interviews with the participants. Fifty four observation sessions, in which it was tried to collect the functioning dynamics, conflicts, tensions, feelings and emotions and identify the educative processes from the participants perception describing and analyzing them. Semi-structured interviews were made with 24 commissions participants (managers, workers and users) in which the participants perception on the educative processes were investigated. The bases of the interviews script were "insertion processes" and "participation". The data analysis emphasized the quotidian and educative processes using the following categories: participation, interaction, and social control on the public health policy. It was concluded that by means of participation, the people discovered new realities, accessed information, developed new perceptions and new abilities. They finished with the fear of exposing themselves and learned to express, give opinion, suggest, discuss, cooperate and creat strategies to accomplishing proposals. Such changes showed the possibility of learning about participation, interaction ande public policy: learn the pratice, learn practing and learn from the practice.
A aprendizagem de polinômios através da resolução de problemas por meio de um ensino contextualizado
(Universidade Federal de São Carlos, 2008-03-20)
Morais, Rosilda dos Santos
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Hartwing, Dácio Rodney
;
https://lattes.cnpq.br/8411023309452408
The objective of this study was to verify how learning of polynomials took place using problem solving in a contextualized learning situation. Thus, the present research was developed in the context of polynomials, based on the construction of cardboard boxes, using students previous knowledge. Based on a bibliographic review of studies on the theme, we defined the categories of comprehension of the concepts: Contextualization, Previous knowledge, and Mathematics teaching-learning-evaluation through problem solving. Since the phenomenon of interest in the study is related to the school, specifically the study of polynomials, it constitutes an intervention of a qualitative nature in a specific situation: a long-term case study. Based on Problem Solving as a teaching-learning method in the classroom, we sought to give students the opportunity to do hands-on mathematics , i.e. develop the content of polynomial in a way that students could collect, experiment, and analyze, in a real-world context, subjacent mathematical patterns. All the work was developed in an interactive situation, with the students divided into groups. This research was carried out over the course of two projects: Project I, conducted with 6th graders in the context of constructing cardboard boxes Polynomials and the operations defined by them (2006); and Project II, conducted with same students one year later, in 8th grade Appropriation of concepts constructed in Project I, and the exploration, based on this work, of the important algebraic concept known as Function . Analyzing the work carried out, we found that the development of the concept polynomial , followed by the concept function , using the manipulation of concrete materials, resulted in more meaningful learning for the students. Starting with a concrete situation, followed by generalization and abstraction in a higher stage of learning, the students, as co-constructors of knowledge, were able to establish relations between the themes addressed throughout the work, within a broader system, where meanings and conventions were being established.
Conformação viscoplástica por rolos a frio e caracterização de substratos de alumina
(Universidade Federal de São Carlos, 2008-03-20)
Koshimizu, Laís
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Morelli, Márcio Raymundo
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https://lattes.cnpq.br/0172837599844991
;
https://lattes.cnpq.br/8051781707103248
Alumina ceramic substrates were conformed by viscoplastic conformation by cold roll pressing in a range of thickness between 100 and 200 µm, which one presents a great technology interesting for eletro-eletronic applications. Among all the techniques of ceramic conformation the viscoplastic processing shows great advantages, allowing the conformation oh ceramic bodies with superior mechanical properties, when compared to the bodies conformed by traditional techniques, such as extrusion, or more complex as tape casting. In this scope, the objective of this work was to verify the potential of viscoplastic conformation by cold roll pressing as a technique to obtain thin substrates, from a high alumina plastic mass prepared in a sigma mixer and extruded by vacuum. In this way, parameters process such as the speed of the rollers and the thickness of the substrates were evaluated, as well as the stages of shrinkage and firing. The final samples were characterized by determination of the microstructure, apparent density and porosity, volume retraction, penetrating liquid and surface roughness. The results showed that the speed of rollers around 15 and 18 rpm provided substrates without the presence of macro defects. Moreover, there s no correlation between the thickness of the substrates and the final characteristics after sinterization, and there s no preferential orientation of the particles when the mass of submitted to plastic deformation. Density superior to 95% of theoretical density were achieved, producing translucent samples and a great homogeneity of the grain size. After the establishment of best conditions for preparation of alumina substrates, they have been applied in the preparation of zirconia substrates with reproducibility of the results, showing that the viscoplastic processing by roll pressing can be an alternative process for the manufacture of ceramic substrates.
Comunidades de aves de uma área do Médio Rio Doce, Minas Gerais, Sudeste do Brasil
(Universidade Federal de São Carlos, 2008-03-25)
Ribeiro, Alan Loures
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Dias Filho, Manoel Martins
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https://lattes.cnpq.br/1346547036069954
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https://lattes.cnpq.br/1772525331556561
Investigação da influência do tamanho das partículas de materiais pulverulentos sobre a força de adesão em diferentes substratos aplicando a técnica centrífuga
(Universidade Federal de São Carlos, 2008-03-25)
Felicetti, Marcos Alceu
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Aguiar, Mônica Lopes
;
https://lattes.cnpq.br/0431688649128529
It was investigated in this work the influence of the size of the particles of the organic and inorganic powdery material on the force of adhesion of those particles and a built substratum of different materials: stainless steel, PVC, Teflon and glass, applying the centrifuge technique for different compression speeds and detachment. It was used for so much a centrifuga (MA - 860, Marconi Equipamentos), whose maximum speed of rotation is of 14000 rpm. The centrifugal speed is generated to promote the compression (press-on) and the detachment (spin-off) of the particles on the surface of the substratum. A program of analysis of images (Image-Pro Plus 4.5) it was used for the collection and the treatment of the images. To determine the adhesion force being used the centrifuge technique, in the headstock of the centrifuga it was necessary to install two tubes, built in aluminum, for the contention of the adapters, also built in aluminum. The purpose of the adapters was of sustaining the substratum containing the particles of the powdery material. After the application of the centrifugal speed of ompression (press-on) and of the count of the particles initially stuck in the surface of the substratum, for the program of analysis of images, the substratum came back for the centrifuga for the application of the centrifugal speed of detachment (spin-off) in different rotation speeds. After each increase of the speed rotacional, the number of remaining particles of the compression was monitored. The material inorganic powdery, phosphatic rock (ρp = 3,07 g/cm3 and dp = 39,38 µm), and the organics, manioc starch (ρp = 1,49 g/cm3 and dp = 25,24 µm) and corn starch (ρp = 1,47 g/cm3 and dp = 23,08 µm), they were the powders used in the investigation of the influence of the force of adhesion particle substratum applying the centrifuge technique. The criterion of choice of the materials for the construction of the substratum and of the type of used powdery material it was your employability in the industry. The diameter strips studied for those powdery materials they were of 8 13 µm, 13 18 µm, 18 23 µm, 23 28 µm and 28 33 µm. The particles of each powdery material were pressed initially on the surface of the substratum centrifuged to a centrifugal speed of private compression, and immediately after this phase, the adhesion profile was determined. All the powders obeyed a log-normal distribution of percentage of particles stuck in relation to adhesion force. It was obtained the force of geometric medium adhesion for all the powders and it was verified that there was a lineal increase with the force of compression applied initially. For polydisperse particles stuck on a surface, the necessary force to separate the particles varies proportionally to your size. And the adhesion force among the particles of the powdery materials used in the experiments and the surface of the different substratum, increased with the increase of the size of the particles and with the increase of the centrifugal speed of compression (press-on). the order of adherence indicated the following relationship for the powdery materials: manioc starch > phosphatic rock, and for the substratum: glass > stainless steel > PVC > Teflon. Using the experimental results in this work, was considered an equation to represent in a more general way the experimental data obtained for the two powdery materials
Biologia de nidificação e estrutura sociogenética intranidal em espécies de Trypoxylon (Hymenoptera:Crabronidae)
(Universidade Federal de São Carlos, 2008-03-26)
Santoni, Mariana Marchi
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Del Lama, Marco Antonio
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https://lattes.cnpq.br/7198095288825585
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https://lattes.cnpq.br/6340546784739707
Female wasps of the genus Trypoxylon (Hymenoptera: Crabronidae) mass-provision their nests with paralyzed spiders. Some species build mud nests; others use preexisting tubular cavities that are divided into a linear series of cells separated by mud partitions. Males of the Trypargilum subgenus mate with the females at the time a nest is initiated and guard the nest until it is completed, helping the female in the building and provisioning activities. In this study, the biology of the nest building and nest genetic structure of four species of Trypoxylon (Trypargilum) T. rogenhoferi, T. lactitarse, T. aurifrons and T. nitidum are shown. The species were sampled using trap-nests (made of dry bamboo stems) in three localities of the state of São Paulo: Araras (three years), São Carlos and Rifaina (two years). These areas were divided in sampling sites. The trap-nests used by the wasps were replaced with new ones and transported to the laboratory and they had the cocoons individually placed in vials. The emerged adults were identified and their emergency, weight and sex were registered. Later, they were stored at -20ºC. Alloyme phenotypes determined through horizontal starch gel electrophoresis were used to the determination of the intranidal relatedness. Some adults were submitted to morphometric analysis of wing traits (length and width of the forewing and hindwing) and mitocondrial DNA analysis. It was collected 2,908 nests of solitary hymenopterans, and 2,478 were founded by Trypoxylon females. Nesting activity was higher in the warm-rainy season (October-March) in these species. The trap-nests used by the different species showed significantly different dimensions. Araneidae was the spider family mainly used for provision, but a species-specific provisioning was observed. The most important parasitoid of the four species was Melittobia. In the three areas, the different species of Trypoxylon coexist temporally but each of them built their nests frequently in a specific site. This result may suggest differential occupation of the habitat. The intranidal architecture of the studied species does not differ from other species of the Trypargilum subgenus: the females divide the nest-trap in sequences of provisioned cells and finish it with the construction of a closure plug. Two types of T. rogenhoferi and T. lactitarse cocoons were found, as observed for other species of the group punctulatum. It was verified that the frequencies of the two types are associated with sex and nest-trap diameter. A possible genetic determination of this character is discussed. A 1 :1 populational sex ratio for the four species was found during all the periods for Araras and Rifaina and the distribution of the sexes inside the nest was not random, where males were frequently found in the first brood cells. Females were significantly bigger than males for the five traits, showing a higher parental investment in females. The developmental cycle in these species last 30 days and a short diapause was observed in T. rogenhoferi and T. lactitarse in the cold-dry season. The allozyme analyses indicated that most of the nests show phenotypes according to a monoginy/monandry hypothesis. Although this result clearly suggest that the male-guard behavior confers him the paternity of the female offspring, some extra-pair matings were also observed.