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Investigações sobre discriminações simples e discriminações condicionais em abelhas
(Universidade Federal de São Carlos, 2012-04-23)
Moreno, Antonio Mauricio
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Souza, Deisy das Graças de
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https://lattes.cnpq.br/4404800720856419
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https://lattes.cnpq.br/8377841191821143
Research on stimulus equivalence constitutes an experimental approach to assess variables underlying the development of symbolic behavior, which depends on the establishment of conditional relations between stimuli. Matching-to-sample procedure is typically used for teaching conditional discriminations, and it has been also used in early studies with honeybees. Bees are capable of learning conditional relations between stimuli, such as specific identity relations, arbitrary relations between visual stimuli, arbitrary relations between colors and odors and generalized identity matching. Therefore, basic processes involved in symbolic behavior could be studied using honeybees as an experimental model. The main objective of the present study was to establish conditional relations in honeybees. Another goal was to test for select and reject-control relations in simple discrimination baselines, since these controlling relations are involved in responding by exclusion. In Experiment 1, eleven bees Melipona quadrifasciata and Melipona rufiventris were individually trained to perform an identity matching-to-sample task. Identity relations were demonstrated by most of the bees. In Experiment 2, four M. rufiventris were individually trained on arbitrary relations. One of these bees demonstrated an increasing trend in accuracy in an arbitrary MTS task over the last sessions. In Experiment 3, twenty Apis mellifera and four M. rufiventris were trained to perform arbitrary relations. Additionally, Apis mellifera bees were presented with a symmetry test. Apis mellifera bees had acquired arbitrary MTS, but Melipona rufiventris performed at chance level. In the symmetry test, Apis mellifera performed at chance level. In Experiment 4, twenty M. rufiventris were individually trained to perform a simple discrimination task. Subsequently, each honeybee was presented to a select and reject control test. Select as much reject control had developed in simple discrimination training with M. rufiventris. On one hand, these data indicate that in most cases the arbitrary matching performance was not accurate. Moreover, symmetry relations did not emerge from training. On the other hand, most subjects responded highly accurately in simple discrimination and identity matching tasks. Most subjects had also demonstrated select and reject-control relations. These advancements in research on basic learning processes in bees may be a promising starting point for investigating the prerequisite repertoires involved in symbolic behavior.
Proposta e aplicação do método das hélices na identificação de estudantes talentosos
(Universidade Federal de São Carlos, 2012-04-23)
Christofoletti, Rui Alexandre
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Almeida, Maria Amélia
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https://lattes.cnpq.br/0316944549621648
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https://lattes.cnpq.br/0797465333922730
The issue of identification is the major factor in an enrichment program to gifted students, because it determines which students will be attended and the criteria used in the identification process. The objective was to develop a method capable of providing a probabilistic interpretation to identify talented students from Renzulli s three rings conception. This research can be defined as quantitative, cross-sectional and correlational, which seeks to establish relationships between the concepts involved in defining giftedness. The methodological approach followed to address the issue of study is: (a) analysis of the different conceptualizations of giftedness, (b) analysis of the various processes of identifying gifted students, (c) reflection on the use of probability in science and (d) development of a mathematical procedure in order to identify gifted students. The identification of gifted students is a challenging task because of the controversy over the definition of Giftedness and its suitability to the school context under study, the subjectivity of some identification methods and the limitations of psychometric tests. The probabilistic interpretation proposed in this work agrees with this view that giftedness is not absolute and is an attempt to minimize the subjective aspects of identification processes. At the same time, due to the tendency of adopting multiple criteria to identify gifted students, the method of Propellers satisfies the need to consider the correlation between the scores obtained by students. Thus, this research presents a new way of evaluating the data obtained in the traditional processes of identifying gifted students. A pilot study was conducted and found that students with equivalent values of the mean of the scores from the identification process had different values of CTC and types of giftedness. The correct interpretation of the parameters proposed must necessarily lead school administrators to work with uncertainty. A student with a CTC value higher than another student is not necessarily more talented. This uncertainty should serve to promote discussion and reflection on how many and which students should be selected to care programs, and the same influence on the structuring of these.
Validação da via de biossíntese de selenocisteína e selenoproteínas em Trypanosoma por RNA de interferência
(Universidade Federal de São Carlos, 2012-04-24)
Costa, Fernanda Cristina
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Thiemann, Otávio Henrique
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https://lattes.cnpq.br/8634678722158858
Selenium (Se) is an essential element found in selenoproteins as the 21st amino acid (Selenocysteine Sec).For the Sec incorporation and the related biosynthetic pathaway, several elements are required: tRNASec, a UGA codon and a Sec insertion sequence (SECIS), a conserved motif downstream of the selenoprotein encoding gene. Selenoproteins generally participate in the cellular redox balance, playing an important role on cell growth and proliferation. These proteins, as well as the the Sec synthesis pathway, are present in members of the Bacteria, Archaea and Eukarya domains, being identified in several protozoa, including the kinetoplastids. Auranofin, a gold-contaning antirheumatic drug, is a known selenoproteins inhibitorand Trypanosoma brucei and Leishmania majorcells are sensitive to this compound, with a LD50 in nanomolar range. This indicates a possible dependence of these parasites on selenoproteins. Theselenophosphate synthetase (SELD/SPS2) is responsible for the formation of monoselenophosphate from selenide and ATP, being essencial for selenoprotein biosynthesis. SPS2 knockdown led to apoptosis under sub-optimal growth conditions. The selenoproteome of these flagellated protozoa consists of distant homologs of the mammalian SelK and SelT, and a novel selenoprotein designated SelTryp, a kinetoplastidspecific protein. The functions of any of these selenoproteins are not known.We have investigated the effect of their downregulation in T. brucei to interpret their possible physiological role. The TbSelK depletion shows no effect on growth under optimal conditions, but the cells became more sensitive to endoplasmic reticulum stress agents and oxidative stress, suggesting that SelK is an ER stress-regulated protein and plays an important role in protecting T. brucei cells from ER stress agent. The TbSelT gene silence by RNA interference hampers the parasite survival, but the sensitivity to the agents tested was not asevident as it was forTbSelK, suggesting a role for TbSelT in protection against stress, but not specifically ER stress. Our results show the importance of selenocysteine and selenoproteins to parasite survival.
O Congresso Nacional e sua participação no combate às atividades ilícitas no Brasil (1988 2010)
(Universidade Federal de São Carlos, 2012-04-24)
Pires, Mônica Sodré
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Diniz, Simone
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https://lattes.cnpq.br/9726360676770459
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https://lattes.cnpq.br/6338002400411488
This study aims to map and analyze the actions and behavior of the Brazilian government and National Congress fighting illegal practices from International acts and domestic legal provisions on the subject. To do so, considering the subject area here classified as "illicit" and the period between 06/10/1988 and 31/12/2010, we take as empirical material, on the one hand, the International acts negotiated by the Executive and approved by the Brazilian National Congress with emphasis on the United Nations Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances; United Nations Convention Against Corruption and United Nations Convention Against Transnational Organized Crime, known respectively as the Vienna, Merida and Palermo Conventions. On the other hand, we take the ordinary laws in the country, with emphasis on the Law nº 9.613 of 1998, Law nº 9.034 of 1995 and Law nº 10.763 of 2003, known respectively as the Law on Money Laundering, Law on Organized Crime and Law on Corruption. We start from the assumption that systemic international activities, and more specifically the International Regimes, were the main factors behind this government action in combating such practices. We conclude that, in most cases, the relationship between the Powers happens in the form of cooperation and that, contrary to common knowledge that attributes the Legislature with lack of interest and delay in certain subjects, the Representatives and Senators are more active than one might initially assume.
Discurso, política e infotainment : uma análise discursiva do CQC
(Universidade Federal de São Carlos, 2012-04-24)
Gon, Laura Colli
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Baronas, Roberto Leiser
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https://lattes.cnpq.br/4613001301744682
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https://lattes.cnpq.br/4192333755686587
Nowadays the amount of academic researchers enrolled with Political and Social Sciences and also with Language Sciences is increasingly growing, which take political events as objects of reflection. However, there are few researches although they are increasing researches- that focus on the placement of these political events on television shows that are part of cyber culture. This study tries to cope with reflection on the placement of political events on the television show CQC (Custe o Que Custar), especially on the composition of its articulation with discursive scenography and with the cyber culture, especially on the study of the so called Infotainment (discourse produced by studying information and entertainment working together). In this investigation, we analyzed four programs shown on September and October of 2010, during the first round of presidential elections in Brazil. To make our goal, which is based on the comprehension of the corpus studied we seek shelter in the theoretical and methodological guidance of French Discourse Analysis especially on Dominique Maingueneau s studies, focusing on the author s ideas on the scene of enunciation : encompassing scene; generic scene and scenography. In addition to that, we also support this study on Oswald Ducrot s polyphonic theory. The methodological procedure is seeking and understanding the images that built the show s discursive scenography our focus is always guided by the interface between description and interpretation, explaining the regularities created by this object of study. We will start the research by discussing what previous studies had studied about the CQC as an object, this is followed by a discussion of the program as a discourse gender and, finally we discuss its discursive scenography s. The results of this study argue that the genre of discourse and historical events are two processes that work together towards the constitution of the interviews scenography from the television show CQC.
Conciliação entre profissão, conjugalidade e paternidade para homens e mulheres com filhos na primeira infância
(Universidade Federal de São Carlos, 2012-04-24)
Vanalli, Ana Carolina Gravena
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Barham, Elizabeth Joan
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https://lattes.cnpq.br/9868595523538592
The need to study work-family balance derives from the experiences of couples who are developing their careers at the same time as they are raising children, and who enter into conflicts at home and at work as a result of the great difficulties that exist to integrate these involvements, in the absence of strategies and supports that would better enable them to establish an adequate level of balance. Focused on couples in this phase of their lives, this study was designed to address two key objectives: a) compare men and women with respect to five factors: personal resources; their professional, marital, household and parental involvements; use of external resources; satisfaction with their involvements; and psychological well-being, so as to identify similarities and differences in the trajectories for each sex, at this stage of their lives; and b) verify the relationships that exist among these five factors, for men and for women, on the basis of the work-family model that underpins this study. As such, an interview protocol was developed, based on a new model of work family balance derived from other models described in the research literature. Individual interviews were conducted with each member of 50 couples, who differed widely in terms of their ages, occupations, and socioeconomic levels. All the study participants were engaged in paid work and were raising a child of up to 5 years of age. The interview protocol included open-ended questions, as well as standardized scales used in other studies in the area of work-family balance. The responses of male and female participants were compared by examining the frequency with which different categories of answers emerged in their verbal accounts, using inferential statistics to compare their results on the standardized scales, and, finally, comparing the relationships that emerged among the five factors included in the theoretical model of work-family balance, using linear regression analyses. The results indicate distinct family and professional trajectories for the men and women who participated in this study. The undervaluing of women s professional work was reflected in the lower salaries paid to the women in comparison with the men. The women also reported greater difficulties than the men to reconcile the demands they faced, together with higher levels of burden, stress and lower satisfaction with workplace support. The strategies used by the couples were marked by the unequal division of family work, reflecting traditional gender perspectives. In a similar vein, the support that was available via organizational strategies was insufficient for both sexes and didn t meet the needs of parents of young children. Given that simultaneous work and family involvements are becoming normative, the results of this study point to the need to create interventions that can prepare couples to more equally share family demands, as well as widening institutional strategies to support workers and introducing public policies that can help couples with young children.
Efeito da visibilidade dos braços sobre a preferência manual e controle motor na ação de alcançar em bebês
(Universidade Federal de São Carlos, 2012-04-25)
Pogetti, Lívia Silveira
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Teixeira, Luis Augusto
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https://lattes.cnpq.br/3456193961124925
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https://lattes.cnpq.br/1009401301199185
This study aimed to evaluate the effect of visual occlusion of the preferred arm on its frequency of use and kinematics in spontaneous reaching of static objects in 5-month-old infants. Participated in this study 30 infants, with half of them submitted to visual occlusion of the preferred arm and the other half having full vision while reaching a toy. A possible cumulative effect of visual occlusion was assessed through increasing periods in which the preferred arm was not visible by the infant. Analysis of manual preference indicated that occlusion of the preferred arm led to increased use of the contralateral arm for reaching, an effect more evident in infants showing weak manual preference. No effect of cumulative occlusion was detected, with similar indices of manual preference across the periods of occlusion. Results from kinematic analysis revealed straighter movements to the target when visually oriented. These results suggest that visual information can modulate manual preference and guide reaching control.
Genética aplicada à ecologia de estradas: um estudo na estrada municipal Guilherme Scatena (São Carlos, SP) e potencial impacto na biodiversidade local
(Universidade Federal de São Carlos, 2012-04-25)
Rodriguez Castro, Karen Giselle
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Galetti Júnior, Pedro Manoel
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https://lattes.cnpq.br/7398754661670478
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https://lattes.cnpq.br/0505422022027092
Roads generate a large ecological impact to wildlife by raising barriers among ranges of species originally continuous and for causing road-kills. After road-killing, a morphological identification becomes impossible for the loss of diagnostic features, especially in the case of small vertebrates. Use of molecular tools for identification is an alternative that has shown successful results, especially when looking towards the species level. We identified samples from animals road-killed, collected on Guilherme Scatena road, through the use of DNA barcode markers, contributing to the local biodiversity knowledge. Another objective was to know the places that have a higher incidence of road kill and the type of landscape coverage in them. During 20 weeks we collected 123 vertebrates: six mammals (5% of total), 30 birds (24%), 38 amphibians (30%) and 49 reptiles (40%), which meant an average of 0.051 animals/Km road-killed. Through morphological characteristics and molecular (mitochondrial genes cox1 and 16S) we identified 111 samples until species status. Analyses among taxonomic classes showed significant differences, confirming that the effects of roads on biodiversity are taxon-specific. We found 19 different types of landscape around the road, being the most common farm buildings and pasture, showing the strong anthropic pressure on environments of this region. The results shown in this study are intended to be an important basis for planning future actions that provide the best management of this area rich in endemic biodiversity of the Brazilian cerrado, as well as mitigation measures to lessen the impact caused by the road.
Avaliação das inter-relações entre função cardiopulmonar e mediadores inflamatórios no diabetes mellitus
(Universidade Federal de São Carlos, 2012-04-25)
Francisco, Cristina de Oliveira
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Leal, Ângela Merice de Oliveira
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https://lattes.cnpq.br/7202663545989206
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https://lattes.cnpq.br/7665896448082766
Diabetes Mellitus (DM) is associated with many complications, including impairment of cardiorespiratory fitness and pulmonary function. Increasing evidences has suggested that comorbidities and systemic inflammation may be involved. The objective of this study was to evaluate cardiorespiratory function in rest and exercise in adults with DM and to verify the relationship between inflammation. Nineteen men with diabetes (51,16 years ± 5,92) and nineteen control subjects (48,79 years ± 7,47) were studied. All individuals were subjected to incremental cardiopulmonary exercise test in cycle ergometer, spirometry, intracellular cytokine lymphocyte profile, lipid and c-reactive protein (CRP) plasma concentration. In the exercise test, maximal overload (W), peak heart rate (HRpeak), oxygen consumption at peak (VO2peak) and at anaerobic threshold (VO2AT), respiratory exchange ratio (RER) were significantly lower in patients with DM than in control subjects. Control subjects and individuals with DM were not different in age, blood pressure, lipid and CRP plasma concentration and intracellular cytokine lymphocites production of TNF-α, IFN-γ, IL-4, IL-10 e IL-17. No significant differences were noted in pulmonary function variables, but abnormalities in these data were predictors to DM. In conclusion, the results confirm impairment of the cardiopulmonary fitness in subjects with DM. The inflammation associated with DM might be influenced by other factors absent in our sample. In addition, the data suggest spirometric abnormalities as predictive to diabetes mellitus.
Inovações na produção de hidrolisados de soja: modelagem e análise econômica de processo
(Universidade Federal de São Carlos, 2012-04-25)
Pretto, Cristine De
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Costa, Caliane Bastos Borba
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https://lattes.cnpq.br/1602653870311562
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https://lattes.cnpq.br/6766872282137948
Soybean and its derivatives have the desired properties for food either for humans or various animals because of its high protein content, which is associated to a good balance of amino acids. However, when the protein is hydrolyzed into smaller peptides, the nutritional value can increase further. A product with high nutritional value added but which does not present economic viability is not interesting for the industry. To analyze such viability, there are softwares that simulate and analyze a process plant. Thus, this study is two-fold: the mathematical modeling of the hydrolysis process and a preliminary analysis of economic viability. Concerning the modeling, two models were fitted: one that relates time with the degree of enzymatic hydrolysis of proteins of concentrated soybean meal and another that relates the degree of hydrolysis with the molecular weight distribution of the pseudocomponents. The analysis of economic viability was conducted using software SuperPro Designer. For this purpose, a degree of hydrolysis and its molecular weight distribution was chosen, and then, an industrial plant was modeled and simulated in a preliminary project level. For the kinetic model, hydrolysis was conducted in laboratorial scale, using a pHstat and an enzyme called Novo-Pro D. The product was analyzed by liquid chromatography. The data were analyzed and the ones obtained in the best conditions were used to fit the model. The best conditions were 55oC, pH 9, 90% humidity, 0,5% m(enz/sub). The kinetic fitting was well described by the Michaelis-Menten with competitive inhibition and neural network described with high fidelity the relation between the concentration of the pseudocomponents and the degree of hydrolysis. Regarding the analysis of the preliminary project of an industrial plant for the production of hydrolyzed protein of concentrated soybean meal, the plant was economic viable, but the project is in a very preliminary stage, due to a lot of unknown data so they were estimated increasing the uncertainty of results.
A Escola de Sargento das Armas: um estudo sociopolítico sobre a formação de praças do exército
(Universidade Federal de São Carlos, 2012-04-25)
Atassio, Aline Prado
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Villa, Marco Antonio
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https://lattes.cnpq.br/7695077592581355
This research aims at finding out about the perspectives of the future sergents of the Armed Force, graduated by the Escola de Sargento das Armas (EsSa). There are few studies about sergents within the Brazilian Social Science, therefore the importance of this research. Among the general focus of this research are the sergent history, their academic education within time and the quotidian os EsSa studentes. The study presents statistics that aims at showing the students´ social origin and interviews that present thestudents´ history and their longing about their career. We have used several scientific methods to conclude this theses, such as bibliographical research, semi-directed interviews, statistics and field research. The result has showed that most of the sergents are from low class families, from the south and south-west parts of Brazil, with age rate between 19 and 25 years-old, without militares parents and high-scholl graduated. However, they don´t show either greater oportunities of advance in theis studies neither possibilities of garantee a career outside the Arm. This confirms the theses that the Arm is used, historically, as a mean of social scaling form those that are in the lower part of Brazilian social pyramid.
Catalisadores Ni/BaO-Al2O3 e Ni/BaO-SiO2 para reforma do metano com CO2
(Universidade Federal de São Carlos, 2012-04-26)
Almeida, Janete Cavalcante
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Assaf, José Mansur
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https://lattes.cnpq.br/9563312407691130
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https://lattes.cnpq.br/3437805220991791
In this work the activity of nickel catalysts were appraised regarding the dry reforming of methane. Due to the low surface area, the catalysts were supported on SiO2 and Al2O3, in order to verify the effect of the support on the catalytic activity. For that, catalysts 12%Ni/xOBa/SiO2 and 12%Ni/xOBa/Al2O3 (x=6, 8 and 12%) were prepared, characterized and submitted to catalytic assays in the methane reforming reaction with carbon dioxide, with the objective of evaluating the effect of the addition of barium to the support. The catalysts were prepared by the wet impregnation method and characterized by powder x-ray diffraction, nitrogen physisorption by the B.E.T.method, area, volume and pore radius, temperature programmed reduction with H2 and X-ray fluorescence. The catalytic assays showed that all the catalysts were shown active in the dry reforming of methane and the conversion of the products was dependent on the type of catalyst appraised. According to the obtained results, they stand out the catalysts with 12% barium in mass addition supported on SiO2 as well as Al2O3.
Participação do óxido nítrico encefálico no controle cardiovascular de rã-touro, Lithobathes catesbeianus
(Universidade Federal de São Carlos, 2012-04-26)
Zena, Lucas Aparecido
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Bícego, Kênia Cardoso
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https://lattes.cnpq.br/0169967378071426
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https://lattes.cnpq.br/3847299377846753
The goal of the present study was to determine if nitric oxide (NO) acting on brain of frogs presents an inhibitory tonus on mean arterial blood pressure (MAP) and heart rate (HR) by reducing the sympathetic activity dependent on α and/or β adrenergic receptors during winter and spring/summer seasons. Thus, body temperature and MAP was measured by a telemetry device implanted into the abdominal cavity of American bullfrogs, with the catheter of the device inserted into the left aortic arch for AP and HR measurements. Additionally, blood cell flux was measured using a laser Doppler flowmeter sutured to the pelvic skin to calculate cutaneous vascular condutance (CVC). A guide cannula was implanted into brain lateral ventricle for injections of L-NMMA (non selective NO synthase inhibitor) or mCSF (mock cerebrospinal fluid, vehycle) and a PE cannula was inserted in the femoral vein for bolus injections of adrenergic antagonists, prazosin (α1) and sotalol (β), and agonists, phenylephrine (α1) and isoproterenol (β) or Ringer solution. Animals were maintained at 25 °C during all the experiments. Mean AP, but not HR, was greater during winter than spring/summer. L-NMMA increased MAP, but did not change HR, during both seasons. The pre-treatment with prazosin attenuated and soltalol accentuated the hypertensive effect of LNMMA in both seasons. We conclude that NO seems to act on the brain of frogs as a hypotensive agent via, at least in part, the inhibition of the symphathetic activity dependent on α, and β, adrenergic receptors.
"Escrevo numa língua que não é minha.": apontamentos sobre processo de ensino e aprendizagem da língua portuguesa escrita por surdos alfabetizados
(Universidade Federal de São Carlos, 2012-04-26)
Sant'Anna, Telma Gomes Novato
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Brito, Maria Isabel de Moura
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https://lattes.cnpq.br/2263321059248030
In an educational context of Strong worldwide movement in favor of inclusive education, which proposes to accommodate all students regardless of their beliefs, race, socio;economic status, or the ones who have physical, sensory, or intellectual disabilities, this research aims to investigate, discuss (and glimpse) paths to the acquisition of written Portuguese by deaf students. For this purpose, the analyzed data were collected in a public school, especially in the Portuguese language classes at Atendimento Educacional Especializado (AEE; Specialized Educational Services). The select subjects were two deaf teenage girls, who, in the academic year of 2011, were regularly enrolled in the first year of high school and attended, twice a week, the AEE. After introducing a brief history and legal aids of the education of deaf students, this study discusses, articulating the bilingual proposal, in which Portuguese is a second language, and the operation of this language and speech as constitutive activity of the individual, the practices of writing texts by deaf students in their social and academic spheres. The data analyzes shows that the mediation is the crux of the whole process. It is through mediation, that is to say, in a joint activity with an adult user of both languages, that the deaf student is captured by the written language to make is work as a resource for interaction and dialogue according to what to say, the reason to say, to whom say and constitute himself as an individual who says what he says to whom he says. (Geraldi, 2003, p.137)
Síntese de nanopartículas de ouro por precipitação
(Universidade Federal de São Carlos, 2012-04-26)
Weber, Alfredo dos Santos
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Giulietti, Marco
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https://lattes.cnpq.br/7703659740618915
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https://lattes.cnpq.br/6205261310692247
Gold nanoparticles have properties with great interest in applications in biomedicine, catalysis, optics and electronics. This study seeks to produce stable, size-homogeneous and well-dispersed particles. The chosen method is the reduction of metallic ions by organic salts in aqueous medium. The organic compounds act as stabilizers and their interactions with the metallic surface defines the particles final characteristics. Sodium citrate was tested as reducing agent. The influence of operational parameters such as temperature, acidity, stoichiometric relations in the nucleation, growth process and size particle was tested. Spectroscopy of UV-visible, scanning and transmission electron microscopy were used as characterization technics. It was concluded that increasing the temperature the particle size and the standard deviation decrease and the produced particles are more uniform in morfology. The nucleation is favored for higher temperatures of reaction, for lower acidity and higher concentration of sodium citrate solution. The particles are formed by clusters which agglomerate and nanowires that incorporate into the face centered cubic crystal structure. UV spectroscopy was efficient in evaluating qualitatively the reaction development and the growth of particles. And with that technique it was observed that transverse polarization of the particles was predominant. The reaction conditions temperature of 80ºC, initial pH of the citrate sodium solution in 8 and 10 e molar relations about 5 produced particles with narrow size distribution and 17 nm of median diameter.
Avaliação do comportamento mecânico de nanocompósito de PEEK/nHA sob curta e longa duração para aplicação como biomaterial
(Universidade Federal de São Carlos, 2012-04-27)
Rego, Bruna Turino
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Bretas, Rosario Elida Suman
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https://lattes.cnpq.br/2805349172281345
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https://lattes.cnpq.br/3217820661976976
The main objectives of this dissertation were to study the short (tensile and impact) and long-term (fatigue) mechanical behavior of nanocomposites of poly(ether-ether-ketone), PEEK, with nanohydroxyapatite, nHA, for application as biocompatible materials. First of all, a preliminary study was conducted to determine the influence of the addition of nHA in the rheological, thermal and dynamic mechanical properties of PEEK, in order to choose an optimal formulation for large-scale preparation. The chosen composition with 10wt% of nHA was prepared by melt mixing in a co-rotating twin screw extruder. The resulting structure and dispersion were characterized by scanning electron microscopy (SEM) and rheological properties. Subsequently, the materials (PEEK and PEEK/nHA nanocomposite) were injection molded at 3 different conditions by varying the flow rate. The resulting morphologies were evaluated by polarized light optical microscopy (PLOM) and the degree of crystallinity of the samples was evaluated by differential scanning calorimetry (DSC) and wide angle X-ray scattering (WAXS). The mechanical properties of tensile, impact and fatigue of PEEK and nanocomposite were measured and correlated with the results of dynamic mechanical thermal analysis (DMTA) and the resulting morphology. It was found that the variation of the injection conditions did not change the materials properties significantly; however, the obtained long and short-term mechanical properties of the nanocomposite were within the range of cortical bone properties and, therefore, the nanocomposite can mechanically be used for medium load bearing implant applications, due to their limited modulus. Finally, tests with adult stem cells to determine in vitro biological response of the biomaterial were performed, which indicated that these cells proliferated faster in PEEK/nHA, indicating that the biological response is most favorable to the nanocomposite than to pure PEEK.
Mulheres migrantes no contexto das fronteiras de gênero e arranjos familiares
(Universidade Federal de São Carlos, 2012-04-27)
Angelin, Paulo Eduardo
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Truzzi, Oswaldo Mário Serra
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https://lattes.cnpq.br/5005536921435787
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https://lattes.cnpq.br/8537328900369894
The objective of this research was to understand the trajectories of migrant families and, especially, the life trajectories and social roles assigned and represented in society and specifically in the processes of migration, women migrants and northeastern Paraná, living in a neighborhood of the city of São Carlos, São Paulo, called city Aracy, always considering the origin, the regional culture, socioeconomic status and family arrangements. For the achievement of this study were performed in a first phase, conversations with authors who discuss the theme of migration, whether international or domestic were performed. A dialogue with theorists who portray the issue of gender, male domination and sexual division of labor, as well as authors who address the notion of family arrangements was also made. Finally, we worked with authors who discuss women's participation in migratory flows and the coordination and mobilization of kinship networks. Then, through qualitative research, interviews were conducted with 33 migrant women, using a guide and semi-structured individual interviews, which was built as advanced research and theoretical literature. The research shows that women migrants women in question, according to the socio-cultural and family, play different social roles. Family and living arrangements decisively influence the representation of these social roles. But other factors such as the origin, regional culture, the weather conditions and socioeconomic status, may influence these representations, to the point of women from the same family arrangement, act differently in society in general and in the migration process.
Formação de mesoporosidade em zeólitas ZSM-5: avaliação do método de preparação e do potencial como catalisador ácido através do craqueamento de cicloexano
(Universidade Federal de São Carlos, 2012-04-27)
Silva, Edilene Deise da
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Urquieta-González, Ernesto Antonio
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https://lattes.cnpq.br/3672771633840838
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http://lattes.cnpq.br/2389975677904655
Due to their potential as acid catalyst and hydrothermal stability, USY, ZSM-5 and modernite zeolites are widely used in several processes of petroleum refining and petrochemical industries. With the discovery of new reserves in Brazil, the petroleum industry must adequate its technology to be able to process heavy oil fractions and satisfy the increased demand for more valuable derivatives (gasoline, diesel and olefins). To achieve this, a better performance of such zeolites needs to be reach by improvement of the active sites accessibility and/or diminishing the diffusion path inside of their microporous system. In this context, the objective of this research was to synthesize ZSM-5 zeolites with hierarchical pore structure and evaluate their potential as acid catalyst in the cracking of hydrocarbons, using cyclohexane as model molecule. In the synthesis of these materials, Black Pearls 2000 carbon and an organosilane surfactant molecule were employed as structure-directing agent for mesopores formation. Zeolites were characterized by X-ray fluorescence, X-ray diffraction, nitrogen physisorption, small-angle X-ray scattering, scanning electron microscopy, nuclear magnetic resonance of 27Al nucleus, Fourier transformed infrared spectroscopy and ammonium temperature programmed desorption. The properties and acid activity of the synthesized zeolites were compared with a ZSM-5 zeolite without mesopores. The results revealed that the used synthesis methodologies were effective in the formation of crystals of ZSM-5 zeolite containing the intrinsic micropores of the MFI structure combined with the presence of intracrystalline mesopores. The Black Pearls 2000 carbon generated mesopores that were an inverse replica of the carbon particles with an average diameter of 12 nm and the amphiphilic surfactant mesopores with diameters of about 4 nm. The cracking of cyclohexane showed that the solids with hierarchical structure of pores preserved the acid potential of ZSM-5 zeolites, with all the micro-mesoporous zeolites presenting similar catalytic behaviour related with the yield and selectivity in the considered reaction. Other hand, the presence of mesopores favoured the formation of products resulting from isomerization and hydrogen transfer reactions.
Influência da orientação corporal no desenvolvimento do controle de cabeça de lactentes
(Universidade Federal de São Carlos, 2012-04-27)
Lima-Alvarez, 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
Head movements play an important role in typical motor development because they form the basis for the emergence of fundamental motor skills such as reaching and sitting. In addition, the head is the first part of the body to develop antigravity control, and serve as a frame for the organization of postural control. The aims of this longitudinal study were: 1) to provide information about the behavioral (frequency of head movement; proportion of head initial position to the right, left and midline; proportion of movement type sideto- midline, midline-to-side and side-to-side) and kinematics (amplitude of head movement: flexion, inclination and rotation; duration of the movement; mean angular velocity; peak velocity; deceleration index; number of movement unit; number of movement unit after peak velocity; mean duration of movement unit; mean duration of movement unit after peak velocity; duration of the longest movement unit) changes during the acquisition of head control in supine position; 2) to verify and to describe the age-related changes observed in the spatial-temporal organization of the head movement; 3) to verify e if different body orientations (unsupported supine; supported supine head supported and semi flexed approximately to 15° over an infant pillow; and supported reclined- head supported and semi flexed approximately and the body reclined to 20° with the horizontal plane) and if external head support can improve the alignment between head and trunk, thus turning the head movement more controlled and 4) to verify if the body orientation can facilitate the head movement in younger infants (from birth to two months), as they head movement are not as controlled as older infants. To this end, 17 infants were longitudinally assessed once a month. They were presented with a black and white card that was moved sideward in front of their face in all the conditions (unsupported supine, supported supine and supported reclined. Results of study 1, focused in the age-related effect of head movement showed that with age, particularly from two months onwards, the head was more often held at body midline. A larger amount of head movements and an increase in amplitude and speed of the head movement accompanied this change between two and three months. Kinematic analysis also showed that head movements were organized in movement units that increased in number until three months of age, but significantly decreased afterwards (especially the number of movement units after peak velocity). The results about body orientation manipulation, study 2, showed that the behavioral and kinematic analyses in the supported supine and supported reclined conditions, showed an increase in the proportions of head positions at the body midline and midline-to-side head movements in comparison to the unsupported supine condition. Further, a lower mean angular velocity and a prolonged duration of the head movement and its constituent movement units (including the longest movement unit) were observed in the supported supine and reclined conditions. The results suggest that the velocity profile became more symmetrical with age, especially after two months-old onwards, which is indicative for better and more efficient control of the head movements. Importantly, many of the differences only occurred when infants were younger than three months of age. In sum, vii the head movement became more fluent and well-organized through age, especially after three months. The external support of the head led to an improvement in the alignment of head and trunk, which promoted better-controlled head movements, especially in the younger infants. This suggests that neck muscle strength is an important limiting factor in the development of head movements.
Toxicidade do cádmio em uma cadeia alimentar constituída por uma microalga (Scenedesmus quadricauda), um cladócero (Simocephalus serrulatus) e um peixe (Hyphessobrycon eques)
(Universidade Federal de São Carlos, 2012-04-27)
Souza, Jaqueline Pérola de
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Melão, Maria da Graça Gama
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https://lattes.cnpq.br/8342306603661310
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https://lattes.cnpq.br/2320506014760329
The effects of trace metals contamination in aquatic environments are of concern in the ecotoxicological point of view. In these environments the organisms are exposed to metals in the dissolved form and also through ingestion of contaminated food in the food chain. The phytoplanktonic organisms are the basis of food chains and are responsible for primary productivity. Zooplankton is a link between primary producers and higher trophic levels, such as fish. The exposure of these organisms to metals will cause changes in the physiology, affect productivity rates, and the balance and dynamics of aquatic communities. This study evaluated the effects of the metal cadmium (Cd) on an experimental freshwater food chain involving the algae Scenedesmus quadricauda, a cladoceran daphinidae, Simocephalus serrulatus, and the fish Hyphessobrycon eques. Cultures of S. quadricauda in exponential phase growth were exposed to 1.6x10-9; 3.2x10-8; 6.7x10-8; 1.6x10-7 and 1.3x10-6 mol L-1 of total dissolved Cd for 96 h. During exposure chlorophyll "a", population growth, coenobia size, and dry biomass were evaluated. Then the contaminated algae were given as food to the zooplankton S. serrulatus during the complete life cycle of the organisms in the concentration range of 3.8x10-14 to 5.9x10-12 g Cd cell-1. During the exposure the embryonic development time, age at first reproduction, time for egg production, generation time, longevity, fertility rates, feeding rates, secondary production, and recovery of the animals were evaluated. Then the cladocerans reared with Cd contaminated algae were used as food for the fish H. eques duruing a period of seven days. At the end of this exposure, we evaluated the histological structure of gills and liver, and the fresh weight of the animals. In S. quadricauda, there were damages on the chlorophyll content, and in the population growth at high concentrations of the metal. In the cladocerans were detected increase of the embryonic development time, age at first reproduction, and generation time, whereas a decrease of the longevity, fertility rates, feeding rates, and secondary production. The rate of secondary production showed recovery after removal the contaminated food. The histological patterns of gills and liver, as well as the fresh weight of the fish were not affected by the Cd exposure tested through the food chain considering the exposure period and concentrations tested. The results indicated that food can be considered an important vehicle in the Cd transfer from phytoplankton to zooplankton in aquatic food webs. Cd has a high potential for toxicity, impacting the producers and primary consumers. However, no Cd effects to the fish, the third trophic level, were detected. These studies are of great importance for understanding Cd behavior in aquatic environments, as well as its toxicity to the organisms. The understanding of these aspects contributes to adaptation strategies for the conservation of aquatic ecosystems in situations of contamination.