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O uso da rede social de aprendizagem Edmodo como auxílio no processo de ensino-aprendizagem
(Universidade Federal de São Carlos, 2014-04-16)
Trova, Nilson Francischini
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Arantes, Alessandra Riposati
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https://lattes.cnpq.br/6742903299047989
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https://lattes.cnpq.br/5648453482403323
The use of computers and the Internet has become necessary in all sectors of society, including the education sector. The Internet has changed our ways of teaching and learning, accessing information and communicating. In this context, we wanted to investigate the use of these resources as tools to assist the teacher in the teachinglearning process. We assess the pedagogical potential of the Social Learning Network Edmodo, which has layout and functionality similar to Facebook and virtual learning environments. Within Edmodo we worked mainly with messaging and Learning Objects related to Dynamics, in the Physics course of high school students. We investigated the potential use of learning objects through forums where students discussed problem situations involving these resources. We observed that the use of the Social Learning Network Edmodo helped the teaching-learning process, motivating students and allowing them to develop critical thinking, acquire new skills and deepen already learned concepts. Besides the research with the students, we also present our impressions regarding the feasibility of using this tool from the point of view of other teachers, who participated in short courses on Edmodo.
Produção de audiovisuais no processo de ensino-aprendizagem: uma proposta avaliativa
(Universidade Federal de São Carlos, 2014-04-16)
Rezende, Eduardo Vieira de
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Arantes, Alessandra Riposati
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https://lattes.cnpq.br/6742903299047989
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https://lattes.cnpq.br/4367575187761889
This work aims the development an evaluative proposal pointing criteria that may be used by teachers in the production of an audiovisual physics program that approach key contents for the understanding of various natural phenomena processes. The audiovisual production efficiency by high school students was already proved in the literature, however, in most of the times, teachers without a starting point aren't able to evalute because both how to and evaluating criteria aren't well defined. In methodological terms, students were encouraged to develop an entire script recording from theme to completion and the film editing as well. At this point, the teacher uses an interdisciplinary work with writing teachers, regarding to the linguistic aspects of the script. Concept, specific physics, and language, referring to structural issues of language: criteria linked to the review of the script, which was divided into two great moments were presented. We have observed that the students' audiovisual production is a way to motivate the research, the work group and the immersion in a meaningful school environment. The results obtained in this study has allowed the development of criteria that will be used to evaluate the efficiency of an audiovisual production by high school students. We conclude that the criteria used to assess these audiovisual projects were satisfactory, ranging from the development of scripts to the final production post on youtube. In this work, the assistent teacher can lead students to implement instructions in their classrooms. Furthermore, we've also developed an evaluative proposal which points different criteria that could be used to assess these audiovisual produced. It's important to say that each criterion was evaluated under teacher's responsability. Finally, the results of this dissertation has pointed to ways to evaluate audiovisual projects and incorporate more criteria to them.
Avaliação da atividade antimicrobiana da N,N,Ntrimetilquitosana e da quitosana comercial sobre o crescimento de bactérias gram-positivas e gram-negativas e de fungos filamentosos
(Universidade Federal de São Carlos, 2014-04-16)
Silva, Leandro Prezotto da
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Seleghim, Mirna Helena Regali
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https://lattes.cnpq.br/5998337634888263
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https://lattes.cnpq.br/8461731975214767
Many efforts have been dedicated in the searching of natural compounds which are suitable to be applied in food conservation. Among them, the chitosan has presented promising results concerning the antimicrobial activity, structural preservation and delay of fruits senescence. However, the chitosan, as found commercially, is soluble only in acidic medium solutions what is considered a hindrance for fully applications as food conservative. In this sense, chitosan derivations which are able to be solubilized in neutral pH have been developed. The N,N,N Trimethylchitosan (TMC) is one of them, characterized as a hydrosoluble derivative of chitosan, which has been considered as an efficient antimicrobial agent with positive action as fresh food conservative. The aim of the present was the evaluation of the antimicrobial activity of the TMC against Gram-positive and Gram-negative bacteria and filament fungi. The TMC antimicrobial activity was assessed by comparing with the Commercial Chitosan (CC), by means of the determination of the Minimum Inhibitory Concentration (MIC), following the Clinical and Laboratory Standards Institute (CLSI) according to M7-A6 (NCCLS, 2003) and M38-A (NCCLS, 2002) standards, both recognized by the Agência Nacional de Vigilância Sanitária (ANVISA). Additionally, the TMC and CC antifungal activity was carried out by recoding the visual fungi growth and estimated from the percentage of infected samples by the fungy on cut faces of grape-tomatoes (Solanum lycopersicum variety cerasiforme), in coated and non-coated conditions, along seven days of incubation. The results concerning antibacterial activity points to a greater action of the TMC when comparing to some analysis performed on CC coating against four of the six strains analyzed: Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Salmonella enterica. Nevetheless the CC antifungal activity was considerable superior to that observed to TMC for three different fungi tested: Penicillium sp., Aspergillus flavus standard and Aspergillus flavus wild. However, both polymers showed high antibacterial and antifungal activity and are therefore considered as natural agents with relevant antimicrobial potential for the fresh food conservation.
Graftização de anidrido maleico em polipropileno, por extrusão reativa, na presença de nanopartículas: estudo de reação e monitoramento in-line
(Universidade Federal de São Carlos, 2014-04-17)
Muñoz, Pablo Andrés Riveros
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Canevarolo Júnior, Sebastião Vicente
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https://lattes.cnpq.br/4153664441338178
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https://lattes.cnpq.br/1950683419725387
The grafting reaction of maleic anhydride onto polypropylene by reactive extrusion, in presence of nanoclay, was studied. The organoclay (Cloisite 20A) was used as support for dicumyl peroxide (DCP), and different amounts of clay were used. The increment in the clay amount leads to reduction in the reaction rates, because it hinders the peroxide release, once organoclay absorbs partially the peroxide. Changes in the reaction mechanisms, in presence and absence of clay, were performed in a Haake internal mixing chamber, between 1 and 7 min of reaction. The results showed changes in the number, and length of maleic anhydride grafting, and in the molar mass. The reactive extrusion of polypropylene with maleic anhydride was studied based in central composite experimental design, using as factors the maleic anhydride and dicumyl peroxide concentrations. The experimental design was analyzed by ANOVA and shows that the increment in clay, used as peroxide support, leads to decrease in the grafting reaction of short succinic groups, by the introduction of long succinic groups, because its concentration increases the maleic anhydride homopolymerization. In the same way the increase in maleic anhydride concentration leads to decrease in the PP grafting level, because the maleic anhydride homopolimerization is increased, decreasing the reaction between polymer and monomer. The in-line monitoring of the reactive extrusion showed a good correlation between the light absorption measured and the formation of secondary reaction products, lately identified off-line as poli(maleic anhydride).
Encontros e desencontros nos assentamentos de reforma agrária: estudo sociológico sobre gerações e identidades
(Universidade Federal de São Carlos, 2014-04-19)
Arbarotti, Alexsandro Elias
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Martins, Rodrigo Constante
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https://lattes.cnpq.br/6617183095074852
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https://lattes.cnpq.br/0078278400218160
After some decades since the establishment of the first settlements the question on its continuity as a public policy arises. Thereby, the research sought to investigate how the generational encounters and disagreements in the settlements of agrarian reform took place. Elements that enabled to understand the historic process experienced by these subjects were sought considering their trajectories and experiences. For this purpose the privileged methodological instrument used was oral history through interviews, material that is enriched with secondary data and bibliography. The field research occurred at "Reunidas gathered" in the municipality of Promissão, SP, and enabled to realize that the subjects' motivation to permanence primarily involved the identification with the locality as a place of sossego and tranquility. However, this identity cannot be thought as something fixed, but in transit and constantly reformulated in relation to the place that is, was and tries to be, i.e., a fanciful, plural, contradictory and temporary identity. In consequence of this reformulation, strategies of permanence indicate new forms of work and income that does not necessarily involve agriculture. And finally, this historic moment of transition and generational coexistence revealed significant changes and ressignifications with regard to projects of life and a vision of land and labor when compared to second generation was the first.
Nucleação, crescimento de cristais, relaxação e escoamento viscoso em vidros de diopsídio e diborato de lítio
(Universidade Federal de São Carlos, 2014-04-23)
Cassar, Daniel Roberto
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Zanotto, Edgar Dutra
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https://lattes.cnpq.br/1055167132036400
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https://lattes.cnpq.br/1717397276752482
Heated glasses undergo a variety of kinetic processes, such as crystallization, relaxation and viscous flow, that are very important both scientifically and technologically. In this work, we measured and rigorously analyzed these processes according to several models and theories, for two glass compositions: diopside (CaO MgO 2 SiO2) and lithium diborate (Li2O 2 B2O3). These analyses addressed the following questions: which viscosity model better describes the experimental data? Which viscosity model better describes the structural relaxation kinetics bellow the glass transition temperature? Does the decoupling between crystallization and viscous flow kinetics occur for the studied materials, as reported in the literature for lithium disilicate? The results showed that the MYEGA viscosity model described well both viscous flow and structural relaxation data. Moreover, our results point towards an explanation for the breakdown between crystallization and viscous flow kinetics: it is a phenomenon in which the crystal growth structural units are able to move without cooperative rearrangements if the viscosity is above 5,6(6) 103 Pa s. With our results for lithium diborate, we confirmed Kauzmann s resolution for his own paradox: this glass fully crystallizes before achieving a metastable equilibrium state when kept at the Kauzmann s temperature. This means that such glass cannot undergo the ideal glass transition . These findings are useful for technological processes such as glass annealing, new glass-ceramic microstructure design, and glass making.
Distribuição de Poisson bivariada aplicada à previsão de resultados esportivos
(Universidade Federal de São Carlos, 2014-04-23)
Silva, Wesley Bertoli da
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Salasar, Luis Ernesto Bueno
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https://lattes.cnpq.br/5464564215528609
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https://lattes.cnpq.br/7852733762870256
The modelling of paired counts data is a topic that has been frequently discussed in several threads of research. In particular, we can cite bivariate counts, such as the analysis of sports scores. As a result, in this work we present the bivariate Poisson distribution to modelling positively correlated scores. The possible independence between counts is also addressed through the double Poisson model, which arises as a special case of the bivariate Poisson model. The main characteristics and properties of these models are presented and a simulation study is conducted to evaluate the behavior of the estimates for different sample sizes. Considering the possibility of modeling parameters by insertion of predictor variables, we present the structure of the bivariate Poisson regression model as a general case as well as the structure of an effects model for application in sports data. Particularly, in this work we will consider applications to Brazilian Championship Serie A 2012 data, in which the effects will be estimated by double Poisson and bivariate Poisson models. Once obtained the fits, the probabilities of scores occurence are estimated and then we obtain forecasts for the outcomes. In order to obtain more accurate forecasts, we present the weighted likelihood method from which it will be possible to quantify the relevance of the data according to the time they were observed.
Produção de etanol a partir da fração hemicelulósica do bagaço de cana usando glicose isomerase coimobilizada com Saccharomyces cerevisiae
(Universidade Federal de São Carlos, 2014-04-23)
Silva, Claudia Ramos da
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Giordano, Raquel de Lima Camargo
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https://lattes.cnpq.br/1597673343693376
Glucose isomerase (GI) was covalently immobilized and co-immobilized with baker yeast in calcium alginate beads for ethanol production by simultaneous isomerization and fermentation of xylose or hemicellulose hydrolysate from bagasse. GI was covalently immobilized on glutaraldehyde-chitosan and high protein loads were immobilized (30-68 support mg.g-1). High immobilization yields (100%) and activity recovery (90%) were achieved. Under typical operation conditions of simultaneous isomerization and fermentation (pH 5, 35°C, medium with nutrients and ethanol concentrations up to 70g.L-1) the derivative remained 90% of initial activity after 120 hours. Calcium carbonate was used to maintain the pH in isomerization/fermentation medium higher than 5.0, ensuring high conversion of xylose at 32- 35°C. Accordingly, concentrations of enzyme and yeast in the reactor of 60-120.103UI.L-1 and 50g.L-1, respectively, resulted in better yields and selectivity for ethanol batch production. After consumption of ~ 65g.L-1 of xylose in about 12 hours, 21g.L-1 of ethanol and 14g.L-1 of xylitol was produced. In a medium without calcium carbonate, partial sugar conversion was observed due to the reduction of pH medium, which decreased up to 4.7, causing the inactivation of GI. The treatment of sugarcane bagasse with diluted acid resulted in hydrolysate with 61.0g. L-1 of xylose, 7.3g.L-1 of arabinose, 7.2g.L-1 of glucose, 10.4g.L-1 of acetic acid, 0.53g.L-1 of furfural, 0.06g.L-1 of hydroxymethylfurfural and 4.3g.L-1 of lignin derivatives. Baker yeast was able to produce ethanol from non-detoxified liquid hydrolysate as efficiently as pure xylose medium. Simultaneous isomerization and fermentation using non-detoxified hydrolysate led to 23 g.L-1 ethanol, yield of 0.34g.g-1 and a productivity of 1.8g.L-1.h-1. Continuous process was conducted for 7 days. The operation for longer periods of time will be possible with pH control and microbial contamination prevention.
Complexos de rutênio (II) de interesse biológico: avaliação in vitro e in vivo do potencial antitumoral e genotóxico
(Universidade Federal de São Carlos, 2014-04-23)
Souza, Andréa Prado Carnizello
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Batista, Alzir Azevedo
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https://lattes.cnpq.br/6469642481998660
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https://lattes.cnpq.br/8986638381625450
This work evaluated ruthenium (II) complexes in biological assays in vitro on tumor cells and non-tumor, and in vivo in male Swiss and C57BL/6 mice, as well as the interactions with DNA and BSA were evaluated. The compounds (1) [Ru(dppb)(SpyMe2-N,S)2]; (2) [RuCl (SpyMe2-N,S)2NO]; (3) [Ru(Pic)2(dppb)]; (4) [Ru(Gly)(dppb)(4,4'-mebipy)]PF6; (5) [Ru(Gly)(dppb)(phen)]PF6; (6) [Ru(Tyr)(dppb)(4,4'-mebipy)]PF6; (7) [Ru(Tyr)(dppb)(phen)] PF6; (8) [Ru(Trp) (dppb)(phen)]PF6 and (9) ct-[RuCl(CO)(dppb)(bipy) ]PF6 (where, dppb = 1,4-bis (diphenylphosphino) butane; pic = picolinate; SpyMe2 = 4,6-dimethyl-2- mercaptopyrimidine, 4,4'-mebipy = 4,4'-dimethyl-2, 2'-bipyridine; phen = phenanthroline; Gly = glycine, Tyr = tyrosine, Trp = tryptophan; bipy = 2,2'- bipyridine) underwent a screening evaluation of cytotoxic activity on different tumor cell lines U251, HeLa, MCF7, HepG2 , MO59J and B16F10 and non tumour V79, in different concentrations by XTT method. The compound 9 was selected for the assessment of interactions with DNA and BSA, the genotoxic potential in vitro (V79 and HepG2 cells), in vivo (Swiss mice), as well as to evaluate the antitumor potential in vivo (C57BL/6 mice). In vitro experiments, the compoud 9 was assessed at various concentrations in the tests of interactions with DNA and BSA and micronucleus test. In vivo experiments, animals were treated with different doses of the compound 9 by intraperitoneal route in the micronucleus and comet assays, and subcutaneous route in the evaluating of the antitumoral potential. The micronucleus test in bone marrow and comet in hepatocytes were employed to study the potential genotoxic. For both assays, in vitro and in vivo, groups negative controls (water) and positive (methyl methanesulfonate and cisplatin) were included. The results of in vitro cytotoxicity assays showed that the HeLa and MCF7 tumor cells were sensitive to the majority of the complexes evaluated. However, the compound 9 showed cytotoxicity against all tumor cell lines evaluated, with low IC50 values. In the experiments of interaction with DNA and BSA, the compound 9 showed weak interactions with DNA and hydrophobic interactions for BSA. The results obtained in vitro micronucleus tests for complex 9 showed absence of genotoxicity in V79 cells and in HepG2 tumor cells showed up genotoxic at a concentration of 1.25 μmol L-1. In experiments in vivo micronucleus, the compound 9 was not genotoxic in different doses evaluated. Regarding the comet assay, the results showed an increased frequency of DNA damage in hepatocytes in a dose of 5.0 mg kg-1 b.w. In vivo antitumor test, animals treated with 5.0 mg kg-1 b.w. of compound 9, showed significant inhibition of tumor growth compared to untreated control. In the histopathological analysis, the compound 9 also showed significant inhibition of mitosis in relation to the control group. Most of the compounds evaluated in this study showed in vitro cytotoxic activity on tumor cells, especially in MCF7 cells. The compound 9 showed promising results in biological in vitro and in vivo assays, suggesting that this compound may be potential candidate for chemotherapy in cancer treatment.
Impactos da taxa de juros do crédito rural nas demandas por insumos agrícolas
(Universidade Federal de São Carlos, 2014-04-23)
Gurgel, Gustavo Sawaya Amaral
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Castro, Eduardo Rodrigues de
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https://lattes.cnpq.br/5702172673123334
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https://lattes.cnpq.br/4266290412218984
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Gomes, Alexandre Lopes
Rural credit was implemented in Brazil with the intention of accelerating the process of modernization of agriculture and provides capital for funding, investment and commercialization of agricultural production, it has been offered at rates below market rates. The subsidized interest rates are the main attraction of rural credit and strengthen its importance in agriculture as a financing instrument. But problems such as the concentration of resources in producers with higher income, access to credit and capital substitution may compromise the effectiveness of the credit in their purposes. Some studies have reported positive impacts of rural credit in supply and producers income as well as in demand for agricultural inputs. Given the importance of the agricultural sector and considering all the problems associated with credit, is questioned what impact the rural credit demands in agricultural inputs. The work is based on the theory of the firm in competitive markets, assuming that the producer faces restrictions on the purchase of inputs and minimizes the production cost given a production level. From the minimum cost function derive the conditional demands of inputs, which can be influenced by the availability of credit and its interest rate. In the empirical analysis Transcendental Logarithmic (Translog) function was used, that assumes no restrictions on the relationship between the inputs a priori.
O ensino de estatística no ensino médio através de projetos
(Universidade Federal de São Carlos, 2014-04-24)
Dangió, Eric Giovanni Zenatti
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Sampaio, João Carlos Vieira
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https://lattes.cnpq.br/8286887389013685
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https://lattes.cnpq.br/7841688982583063
The aim of this study was to reveal the results of a teaching experiment involving the efforts made in order to validate the teaching of Statistics in secondary school through projects and practices, which were contextualized and close to the reality of the students. The experiment is based on group work so as to provide students with significant cognitive advance. Didactic engineering was the methodology applied. During the experimentation, we developed a didactical sequence for teaching Statistics in secondary school, presenting the student with practical activities in which he could be the protagonist of the teaching-learning process. The results collected with the didactical proposal as well as the students participation in the activities were faced with the addressed hypotheses for the purpose of process validation. Although the National Curriculum Parameters - PCN for Primary School (Brazil, 1997 and 1998), PCNEM (Brazil, 2000) and PCN+ (Brazil, 2002) for Secondary School suggest that Statistics should be taught since the early grades, this subject is regarded as unimportant. In the state of São Paulo, the contents of Statistics are in the student's notebook, 4th volume of 3rd year of secondary school. However they are rarely addressed in class due to several factors, such as: students indiscipline, the resistance of some teachers to teaching that subject, the location of the content in the notebooks and insufficient time to properly work on the contents. Through the comparison of the results obtained with the analysis of the activities and the students participation, we conclude that the instructional sequence presented favored the development of the teaching and the learning of Statistics in secondary school.
Processos difusionais, cristalização e escoamento viscoso em dissilicato de bário vítreo
(Universidade Federal de São Carlos, 2014-04-24)
Rodrigues, Alisson Mendes
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Zanotto, Edgar Dutra
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https://lattes.cnpq.br/1055167132036400
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https://lattes.cnpq.br/1312261053452256
In this work, we analysed if the viscous flow successfully describes the transport of crystal nucleation and crystal growth structural units that occur at the liquid/crystal interface. In order to do this, we calculated the diffusion coefficient which controls the viscous flow, Dη, from experimental viscosity data using the Eyring equation and compared with diffusion coefficients that control the phenomena of crystal nucleation and growth (Dτ and DU), calculated from experimental measurements of specific heat, viscosity, crystal nucleation and growth. The analysis showed that the diffusion coefficient Dη satisfactorily describes the dependence of the diffusion coefficients Dτ and DU at high temperatures. However, for temperatures below 1.03Tg and 1.19Tg for crystal nucleation and growth, respectively, we observed a phenomenon called decoupling (or breakdown) that is the inability to use Dη. to describe Dτ and DU with temperature. This phenomenon was observed for other glassy materials and the values found in this study are consistent with the literature. All the experimental measurements performed in this study were obtained from the same batch of a stoichiometric glass with composition 33.3BaO.66.7SiO2-mol% where the chemical homogeneity was assessed (and deemed satisfactory) from a probability method using Poisson`s distribution. This work also proposed a new method to quantitatively measure the heating rate that should be used in a DSC furnace to prevent the formation of new nuclei. We then applied this method to the glass 33.3 BaO.66.7SiO2 and obtained the value of 25 °C/min. This value is in reasonable agreement with predictions from the literature that suggest a heating rate equal to 20 °C/min is sufficient to prevent the formation of new nuclei silicate glasses.
Efeitos do treinamento de estabilização funcional em mulheres saudáveis e com dor femoropatelar
(Universidade Federal de São Carlos, 2014-04-25)
Baldon, Rodrigo de Marche
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Serrão, Fábio Viadanna
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https://lattes.cnpq.br/8137335642635433
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https://lattes.cnpq.br/9854034655055173
Hip and trunk strengthening exercises have been included in preventive programs and treatment protocols for patellofemoral pain (PFP). It is believed that the strengthening of these muscles might change the lower limb movement pattern during functional activities, reducing the patellofemoral stress. However, there is limited evidence about the clinical and biomechanical effects of the treatment focused on hip and trunk muscle strengthening and lower limb and trunk movement control, named functional stabilization training (FST). Thus, the objectives of this thesis were to verify the effects of the FST in healthy females, to compare the effects of the FST to the standard treatment (ST) in females with PFP, and to determine the muscle function mechanism(s) by which the FST leads to kinematic changes in the frontal plane. The 3D kinematics was assessed during the single-leg squat using a camera system and an electromagnetic tracking system. The hip and knee isokinetic torque was assessed with an isokinetic dynamometer and trunk muscle resistance was evaluated by way of sustained static postures. The functional performance was evaluated using the single-leg triple hop test, the timed 6-m single-leg hop test, and the Lower Extremity Functional Scale. The pain intensity was assessed with a 10cm visual analogue scale and the Global Rating of Change Scale was used to measure perceived improvement. The results of this thesis demonstrated that the healthy females and the patients with PFP performing the FST decreased the movement excursion of contralateral pelvis depression, hip adduction and knee abduction. Moreover, the patients performing the FST also decreased ipsilateral trunk inclination and increased pelvis anteversion and flexion. The FST was also effective in increasing hip and knee torque and functional performance in healthy females and in the patients with PFP as well as the trunk muscle endurance in PFP patients. The patients who performed the FST also showed less knee pain intensity and greater perceived improvement when compared to the patients who performed the ST. Finally, the strengthening of the gluteus muscles was associated with improvement of lower limb and trunk kinematics in the frontal plane. Therefore, the results of this thesis show that the FST causes significant lower limb biomechanical effects in healthy females and in patients with PFP. Moreover, the FST causes greater clinical improvements in patients with PFP when compared to the ST.
Vespas parasitoides em capítulos de Asteraceae: caracterização da fauna, distribuição e padrões de associação no Cerrado do estado de São Paulo
(Universidade Federal de São Carlos, 2014-04-28)
Nascimento, André Rangel
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Dias, Angélica Maria Penteado Martins
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https://lattes.cnpq.br/8637344058859147
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https://lattes.cnpq.br/1936839223951300
This is the first and most complete study of parasitoid wasps fauna associated with endophagous herbivores reared from flower-heads of Asteracea. A total of 36 remnants of Cerrado were sampled around São Paulo states, Brazil. 15,372 specimens of 192 species of parasitoid wasps were reared from 74 species of family Asteraceae. The subfamilies Eulophidae (Chalcidoidea) and Braconidae (Ichneumonoidea) represented most than a half of parasitoid wasps species. In addition to presenting a rich fauna of parasitoids, this study also addresses ecological issues regarding the main determinants of the parasitoid species richness from Brazilian savannah. The availability of food resources has crucial role in determining the species richness of parasitoids. In the first chapter of this thesis, we verified the role of geographical distribution of plants on the accumulation of natural enemies of their endophagous herbivores. In the second chapter, we verified through a path analysis which was the effect of local richness and phylogenetic diversity of plant species and their herbivores endophagous of flower-heads on local parasitoid species richness. In the third chapter we tested through an analysis of randomization if the patterns of the proportions of species of three trophic levels were consistent or stochastic. We conclude that both plants and their associated herbivores play a key role in determining the species richness of parasitoids in the Cerrado biome and the principals determinants of parasitoid wasps species richness were geographical distribution of plants, plant and herbivore richness, and the phytophysiognomy where species live. Due copyrights, all chapters of this thesis can be found published online in Neotropical Entomology, Insect Conservation and Diversity and Biota Neotropica magazines.
“Compreensão das propriedades estruturais e de superfície de catalisadores de platina promovidos com cério através de técnicas de caracterização in situ sob a reação de deslocamento gás-água”
(Universidade Federal de São Carlos, 2014-04-28)
Meira, Debora Motta
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Zanchet, Daniela
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https://lattes.cnpq.br/0601216568829240
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Bueno, José Maria Corrêa
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https://lattes.cnpq.br/0157452280626031
Pt based catalysts were measured with in situ X ray absorption fine structure spectroscopy (XAFS) to obtain information about the catalyst crystalline structure and electronic properties as a function of catalyst composition, method of preparation, inlet feed conditions and temperature. In these experiments, two type of catalysts were studied: i) nanoparticles of Pt occluded in Al2O3 or CeO2-Al2O3 matrix containing 1.5 % of Pt where two different methods to incorporate the cerium were used and ii) conventional Pt supported catalysts containing 0.3 and 1 % of Pt on Al2O3 or with addition of 6 or 12 % of ceria. For catalysts based on nanoparticles, XAFS spectra were acquired at Pt L3-edge and Ce K and L3-edge under reduction and water gas shift (WGS) reaction conditions. The XAFS results reveal, after the reduction, the presence of Pt nanoparticles with similar coordination numbers (NPt-Pt), about 6, and similar Pt-Pt distances, about 2.75  0.01 Å. The catalyst activity for WGS and the strength of interaction between the metal and the support are related with cerium oxide structure revealed by XAFS analysis at Ce K and L3 edges. In situ infrared spectroscopy under WGS conditions revealed the presence of formates on the catalyst surface and that they are probably spectators for the reaction. It was possible to observe that these catalysts changes according to the atmosphere and temperature. Thus, it was possible to demonstrate, using the pre-formed nanoparticles that several parameters affect the catalyst behavior like: the metallic and the oxide particle size, the contact between them and what is exposed on the surface. For the conventional catalysts, the addition of ceria on 03PtAl sample enhances Pt oxidation, reflecting in a larger Pt-O coordination number for this sample. After reduction, 03PtAl resulted in larger Pt particles compared to the 12Ce03PtAl. For Ce-containing samples, in addition to the Pt-Pt contribution, a Pt-O contribution had to be considered to fit the spectra. This Pt-O increases proportionally to the cerium amount demonstrating that Pt clusters are anchored on support through a Pt-O bond. The Pt structure changes depends on the temperature, support nature and reactants composition, demonstrating that the catalytic properties requires the use of in situ characterization techniques.
Estudo da influência do preenchimento de alvéolos em lajes alveolares submetidas à força cortante
(Universidade Federal de São Carlos, 2014-04-28)
Pinheiro, Gregory Lee
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Almeida Filho, Fernando Menezes de
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https://lattes.cnpq.br/0447825383222965
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https://lattes.cnpq.br/3917156804189914
The use of precast elements has become crescent in Brazil, due to the need of haste during production as well as while assembling the structures. Bearing in mind a quick assembly and the competitive price for this kind of frame, precast elements have been growing and spreading in this field throughout the country. There is something special about demanding hollow core slabs, in virtue of their own low weight, in face of the empty spaces generated by the hollows and a better use of materials because of pretension technique, making it economically feasible. The National Technical Code ABNT NBR 9062, which deals with precast concrete structures, shows no more specific criteria as far as hollow core slabs are concerned, but on the other hand the 2011 review in force to ABNT NBR 14861 which covers precast hollow core slabs brings about relevant aspects such as the method used to check the capacity of shear strength on precast hollow core slabs, both with and without concrete structural cover, and furthermore with and without hollow fillings. Considering the reduced amount of national research on this topic, this study aims to develop and perform techniques in different ways of filling the hollows and the slabs and how they behave when exposed to shear strength tests. As a consequence to the manufacturing process of such type of slab and the hollow- filling method, failure in the idealized filling, in virtue of each material own behavior and inappropriate technique are commonly found.
Concentração, rivalidades e impactos sobre o risco no mercado bancário brasileiro
(Universidade Federal de São Carlos, 2014-04-28)
Bottrel, Mariana Araújo e Silva
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Pitelli, Mariusa Momenti
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https://lattes.cnpq.br/2810339285129049
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https://lattes.cnpq.br/1884762075436436
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Aguiar, Danilo Rolim Dias de
It is essential that the financial intermediaries operate well in order to offer financial products to attend the society s needs efficiently, providing economic growth. Besides, a healthy banking system is extremely important for the solidity of the financial system of a country and the social welfare. Therefore, it is necessary to study the market structure, with their concentration rates and the possibility to exercise market power of the firms. Also, it is possible to relate the impacts of this market structure to the risks taken by the banks. In order to measure the concentration, it has been used the following techniques: (i) Herfindahl-Hirschman Index (HHI); (ii) Concentration Rates ( CR). To watch the possibility of market power exercising and rivalry, two methods were used: (i) unit root tests; and (ii) unit root tests with panel data. The results show that there has been a large increase in concentration, especially during the beginning of the global financial crisis in 2008. Moreover, it shows that there is possibility of effective rivalry. For the relationship between structure and risk, it has been used a model with panel data, according to Araújo e Jorge Neto (2007). The result was that the relationship between risk and concentration is positive. On conclusion, effective rivalry in the markets studied is possible, which reduces the possibility of the exercise of market power due to an increase in concentration. The concentration may also not have contributed to reduce the risks taken by banks. Keywords: Economic Measures. Econometrics. Commercial Bank. Financial Crisis.
Sobre a luz e o silêncio : o plano de longa duração e a dinâmica do som no cinema de Carlos Reygadas
(Universidade Federal de São Carlos, 2014-04-29)
Reis, Hugo Leonardo Castilhos dos
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Miranda, Suzana Reck
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https://lattes.cnpq.br/8566012598222563
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https://lattes.cnpq.br/1644543442424911
This work aims to discuss the cinema of Carlos Reygadas, with the focuses on the importance of sound and its dynamics within the long duration take, a procedure that strongly characterizes the style of this director. Initially, excerpts from films Japón (2002), Battle in Heaven (2005) and Silent Light (2007) were analyzed to highlight the formation of a stylistic corpus and a predominantly contemplative and sensory conception of cinema. Then we elected Silent Light as a conductive thread of a broader analysis in relation to the main crop. Therefore, we had as main references studies by David Bordwell (2008) on traditional directors of the plan-sequence, as well as the categories and theoretical assumptions of Michel Chion (1994, 2009) on the uses of sound in cinema.
Estudo de incorporação de whiskers de celulose em polietileno de baixa densidade (PEBD)
(Universidade Federal de São Carlos, 2014-04-29)
Teodoro, Kelcilene Bruna Ricardo
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Mattoso, Luiz Henrique Capparelli
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https://lattes.cnpq.br/5839043594908917
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https://lattes.cnpq.br/3203774759570089
This research proposed the obtainment of cellulose whiskers from cotton fibers and their application in low density polyethylene matrix (LDPE). Cellulose whiskers was obtained from acid hydrolysis of cotton fibers and the reaction conditions were defined after study of different acid in hydrolysis reaction (under 45°C and 75 minutes, with HCl sample WCl, or H2SO4 sample WS, or mix of them in a proportion 1:1 sample WSCl). The main difference observed was the amount sulfate groups on whiskers surface due the use sulphuric acid in hydrolysis. These groups affected the properties of samples, increasing stability of whiskers in aqueous suspension, decreasing the tendency to agglomeration. However, due to these groups, cellulose is degraded at low temperatures. Once the nanocellulose (hydrophillic) needs to interact with LDPE (hydrophobic), two strategies was studied to compatibilize them: (i) production a nanocomposite based EVA poly (ethylene-covinyl acetate), a copolymer compatible with matrix and filler, since it have a polar phases (vinyl acetate monomer) and a nonpolar phase (ethylene monomer), and (ii) surface modification of cellulose whiskers by esterification reactions. Nanocomposites based EVA was prepared by polymeric solution where EVA was solubilized in mineral oil and then, the whiskers without surface modification (WS) was added, with aim dispersing them in LDPE. The characterizations this study showed that the solvent remained inside the structure polymeric, modifying their original properties and difficulting the interaction between cellulose and copolymer molecules. The sample WS and WCl was applied in esterification reactions with acetic acid, propionic acid and maleic anhydride. Whiskers extracted by hydrochloric acid and modified by maleic anhydride (WClMal), was produced by a simple methodology and presented thermal stability at processing temperatures. Thus, this sample was used to obtain nanocomposites with cellulose whiskers and LDPE, which was produced as films by extrusion process. Nanocomposites with LDPE and whiskers not modified (WCl) was produced to comparison. The characterizations of these materials confirmed the incorporation of whiskers in a polymeric matrix. The concentration that showed good dispersion and lower clusters was 1% (w/w) cellulose whiskers in LDPE matrix.
Mitigação de riscos e compartilhamento de informações na cadeia de suprimentos: efeitos na melhoria do desempenho de empresas agroindustriais
(Universidade Federal de São Carlos, 2014-04-29)
Tomas, Robson Nogueira
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Alcântara, Rosane Lúcia Chicarelli
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https://lattes.cnpq.br/7053457212238829
Empirical works have shown that risks in a supply chain can affect the efficiency of the flows of products, services and information in it, causing misalignment between activities, inefficiencies in operations and low firm performance. In this sense, we note that the inter organizational information sharing has been pointed out in several studies (e.g., LEE et al, 2012; GIUNIPERO and ELTANTAWY , 2004; BLACKHURST et al, 2011) as an element capable of mitigating several risks involved in the productive activities of a supply chain. This thesis fits into this perspective, more specifically, seeks to analyze the relationship between sharing information with suppliers and customers and the mitigation of risks in supply chains (i.e. disruptions, poor delivery performance, failure orders, poor demand forescast, and others). Moreover, it is expected to understand if this fact (risk mitigation) contribute to improving business performance. Thus, we performed an empirical study consists of three stages, namely: i) literature review, ii) conducting a test of hypotheses with data processing by means of the technique of Structural Equation Modeling, and iii) interviews for in-depth understanding of the hypotheses were confirmed. Overall, the results indicate that, for the studied sector, a share of effective and efficient information between the company and its key suppliers focus promotes the mitigation of supply disruptions and inefficiencies in distribution operations or fulfilling delivery times along the chain, even without an appropriate sharing of information on demand (by the closest ties of the final consumer) or occurring inconsistencies with regard to its prediction. Moreover, with respect to performance improvement from the risk mitigation, the results are conclusive and allow to state that the expected effect was confirmed, i.e., so smaller are the risks involving the activities of supply, production and distribution of a focal with its suppliers and customers, best will their performance results (operational , market and financial). As contribution of the study, besides to filling the gaps identified in the literature highlights the production of knowledge to data from the Brazilian situation, since this research focuses on a recent topic (risks mitigation in supply chains) in an industry specific, of agri-companies.