Browsing by Issue Date, starting with "2004-06-23"

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Validação da simulação dinâmica das etapas de evaporação e cristalização da produção de açúcar com dados obtidos em plantas industriais
(Universidade Federal de São Carlos, 2004-06-23)
Jesus, Charles Dayan Farias de
;
Almeida, Paulo Ignácio Fonseca de
The central area of the State of São Paulo, Brazil, where the city of São Carlos is located, is one of the largest world producers of alcohol and granulated sugar from sugar cane. As the market become more competitive, the factories seek for new technologies and more rigorous mathematical approaches. This work is inserted in this context, where partnership between university and industry is encouraged. The key steps in the sugar production process are the evaporation of the juice and the crystallization of sugar. The evaporation stage has great influence in the energy balance of the factories but, in spite of that, its automatic and optimized operation is not completely implemented in a large part of the producing units. By its turn, the crystallization step should be monitored very closely because is in this step that the final product is obtained, so quality issues are critical. In this work, the main aim was to develop non-linear dynamic models of these two important operations. The models used industrial data collected from Usina Santa Adélia (evaporation stage) and Usina São Martinho (crystallization stage). The processes of the two factories were accompanied, analyzed and sampled. A steady-state and a dynamic models of the evaporation were developed using the classical approach material and energy balances. Both models were designed in such way that they depend only on few assumptions and on measurements available on-line. The results obtained with the steady-state model fully characterized all streams of the multiple-effect evaporator and allowed to estimate the steam flow rate bled from the equipment. With the dynamic model it was possible to calculate the concentration of the syrup in the last effect. Comparison between the predicted values and the actual industrial data showed that the model generated estimates in the same range of values and reproduced the behavior of the variable. The analysis of the results suggested that more measurements would be necessary to develop a reliable model (in the process control sense) and demonstrated that it is difficult to use the industrial data in the format they are found in the historical data files. To overcome these inconveniences an artificial neural network was developed as a software sensor for the Brix in the last effect. Several topologies were tested and the results of the best ones were very good. Unfortunately, as the performance of the predictions depends on the quality of the training set, it was necessary a real effort to preprocess all available data. The proposed model for the crystallizer (batch vacuum pan) select in the crystallization stage was constituted by a system of nonlinear algebraic and differential equations. Besides the energy and material balances, the model included the population balance, which allowed the calculation of the average crystal size and its coefficient of variation during the strike. Even with severe assumptions and few input data, the model was able to make good predictions of the rajectories of the state variables of the equipment. The analysis of the results also showed that some aspects of the automatic operation affect the stability of the process. Finally, it could be said that the first principles and the neural network approaches could become powerful, useful and reliable tools to model the stages of sugar production if more sensors were installed in the process.
Estudo e aplicações das técnicas de RMN HR-MAS e DOSY em plantas e extratos de plantas da ordem Rutales
(Universidade Federal de São Carlos, 2004-06-23)
Vizzotto, Lucinéia
;
Ferreira, Antonio Gilberto
;
https://lattes.cnpq.br/3676462220401452
This work describes the implementation of two recent techniques in NMR - DOSY e HR-MAS as a tool for the analysis of natural products mixture and in leaves of Citrus, respectively. The work begun with the technique DOSY, in which a known mixture of two natural products was employed to implement the technique and optimise the experiments of DOSY, DOSY-COSY and DOSY-HSQC. After that, the DOSY experiments was employed in a group of natural products mixtures, in which the technique applicability was assessed. The second part of the work was carried out by the implementation of HR-MAS technique with the experimental conditions optimisation and the technique evaluation in the study of Citrus leaves. The evaluation of the technique was carried out by the distinction among six Citrus sinensis varieties, as the indicator for the defence substances present in leaves of Citrus sinensis grafted in Citrus limonea and the detection and identification of the defence substances in leaves of Citrus spp under the plague attack.
Contribuição ao desenvolvimento de metodologia para detecção de desintegrina recombinante produzida em cultivos de células CHO-K1
(Universidade Federal de São Carlos, 2004-06-25)
Silva, Gracinda Marina Castelo da
;
Zangirolami, Teresa Cristina
;
https://lattes.cnpq.br/4546701843297248
Disintegrins are proteins present in the poison of serpents that have been calling the pharmaceutical industry attention due to their capacity to prevent the progression of cancerous cells. A receiving key-protein called integrin addresses the formation of new blood vessels instructing the tumor cells to increase and spread. The disintegrin acts as an inhibitor that blocks this interaction. In order to produce substantial amounts of disintegrin in industrial scale, its expression in CHO-K1 cells was carried out by cloning the characteristic DNA extracted from the poison producing glands of the serpent Agkistrodon contortrix laticinctus. Usually CHO-K1 cells are cultivated in medium containing bovine fetal serum. However, its presence in the cultivation medium hinders the stages of detection, extraction and purification of the protein of interest. The objective of this work was to study the CHOZMD cell growth and the desintegrin production in serum free medium, as well as to develope a methodology for the detection and quantification of the disintegrin present in the medium. The cultivations were carried in culture bottles of 25cm2, 75cm2 and 150cm2 and later in spinner flask with a volume of 500mL, incubated with an amount of CO2 controlled in 10% v/v, pH between 7.0 to 7.4, a temperature of 37 °C, under agitation conditions. The cells were cultivated in the presence of the microcarrrier Pronectin F which enables the attainment of high cell concentration. The culture media DMEM and CHO-S-SFM II were used in the cultivations by means of a gradual adaptation process for a serum free medium, through the reduction of DMEM+serum proportion at each change, until that it was totally replaced by the serum free medium. The cells were maintained in 100% serum free medium during 6h with the withdrawal of 250 ml after 3 h and of the remaining volume after 6h of cultivation. For the detection of the disintegrin, the samples were initially filtered in Milipore filter, then concentrated in ultra filter Amicon and finally centrifuged in membranes Centriprep and Centricon. The disintegrin, protein of ~70kDa, present in the treated samples was detected using Bio Dot equipment with nitrocelulose membrane incubated with specific antibodies. The samples were applied in ion exchange column and the fractions obtained applied in nitrocelulose membrane. In the cultivations carried out in serum free medium with the microcarrier Pronectin F a maximum cell concentration of 1.74.106 cel.ml-1 was reached, which is slightly inferior to the value reached in the cultivations in medium containing serum (2.7.106 cel.mL-1). However, concerning product formation, the immunodetecion results revealed the presence of the disintegrin in the cultivations carried out with serum free medium. Cultivations carried out in spinner flask, with a volume of 200mL and using microcarrier Citodex 1 and medium supplemented with 1% hemolymph (v/v) presented maximum cell concentration of 2.6.106 cel.mL-1. The detection method developed was effective in the identification of the target protein in the samples from the cultivation medium containing hemolymph. Preliminary tests demonstrated loss of protein might be related to gradual degradation in cultivation medium or retention in ion exchange column.
Incorporação da gestão dos custos do ciclo de vida ao processo de desenvolvimento do produto da EMBRAER.
(Universidade Federal de São Carlos, 2004-06-25)
Freixo, Osvaldo Magno
;
Toledo, José Carlos de
;
https://lattes.cnpq.br/9421627326330417
The Product Development Process (PDP) is one of the fundamental business processes of an organization and therefore should be conducted harmonically with the other company processes, as well as with the established strategies for competitiveness and profitability. One of these strategies is to offer the market products at reduced costs, which is a result of development, manufacturing, operation, maintenance and even discarding products once they have reached the end of their life cycle. These costs, called Life Cycle Costs (LCC), are closely related to Product Development, since the decisions taken during its process define costs in each phase of the product s life cycle. A Product Development Model should include a definition of the activities, information and responsibilities regarding the impact that each engineering decision has on the product s Life Cycle Costs. This definition leads to a LCC Management Model, considered, then, a sub-model of PDP. The objectives of this research were as follows: (a) to incorporate LCC management activities into the PDP of a company, with the participation of people that work with Product Development; (b) based on the literature and the case study developed, to prepare guidelines with recommendations for companies interested in implementing a similar project. The Action-research method was used in the study, and the LCC Management Model was developed at EMBRAER Empresa Brasileira de Aeronáutica S/A (a Brazilian aeronautics company). The main conclusions of our research indicate that the involvement of the people that participate in the PDP is crucial when preparing the LCC management models. However, these people should be adequately prepared to take part in a project of this nature, enabling real management and the implementation of a company culture concerning LCC. The results have also shown that the Action-research method is effective in identifying the opportunities of improvement of the Product Development Process and in proposing Life Cycle Costs management practices.
Síntese e caracterização a nível nanométrico da fase Li2(M) Ti308, M=Zn, Co e Ni pelo método Pechini.
(Universidade Federal de São Carlos, 2004-06-25)
Câmara, Maria Suely Costa da
;
Longo, Elson
;
https://lattes.cnpq.br/9848311210578810
The present work describes the preparation and characterization of the spinel phases Li2ZnTi3O8, Li2CoTi3O8 and Li2NiTi3O8 synthesized by the polymeric precursor method. Polycrystalline ceramic powders of high quality were synthesized for the Li2ZnTi3O8 and Li2CoTi3O8 phases. The desired spinel phase of the Li2NiTi3O8 compound was not obtained, however the synthesis product consisted of other crystalline phases. The chromatic and luminescent properties of the powders were investigated. The powers were calcined in temperatures between 400oC-1000oC/4h, after the obtention of the puff , in a heat treatment at 400oC/1h. The evolution of the crystalline phases with calcination temperature was investigated by means of X-ray Diffraction and Raman Spectroscopy, where it was verified that the Li2ZnTi3O8 and Li2CoTi3O8 crystalline phases could be obtained at low temperature (500oC). The Rietveld refinement method was used to observe in greater detail the crystalline structures of the spinels, and to study the occupations of the octahedric and tetrahedric lattice sites. The particle characteristics were studied by crystallite size and specific superficial area measurements, scanning electron microscopy and transmission electron microscopy. The results show that the synthesized powders present dimensions in the nanometer scale. The pigment of the Li2CoTi3O8 phase presented a green color for calcination temperatures of 400oC (amorphous) and 500oC (phase with structural defects). In temperatures above 600oC, the pigment presented a green-blue color with stability up to 1250oC. The observed pigment color transition from green to blue is due to the cobalt occupation in tetrahedric and octahedric sites. The Li2NiTi3O8 phase resulted in yellow pigments of excellent stability. The non-crystalline Li2ZnTi3O8 phase presented photoluminescent properties. The crystallization of this material provoked the quenching of the photoluminescent emission. A quantummechanical computer simulation confirms that the non-crystallinity of this material induces the formation of electronic levels, reducing the effective band gap energy when compared to the crystalline phase. This might explain the behavior of the photoluminescence in this spinel phase.
Gestão do processo de desenvolvimento de produtos de empresas de pequeno porte de base tecnológica de São Carlos: estudo de casos
(Universidade Federal de São Carlos, 2004-06-28)
Scoralick, Marcela Caldas Leitão
;
Alliprandini, Dário Henrique
This work aims to characterize the product development process (PDP) in three technology based companies established in the city of Sao Carlos, Brazil. It also identifies and analyses management practices used in this process, as well as main problems and trends related to PDP management. In the technology based context, same as others, PDP is a very important process for competitive improvement, mainly when aspects as globalization, product diversification, product life cycle reduction and the need to adapt to innovation. The dissertation includes a literature review about PDP, a discussion on technology based companies and its innovation process, and a report of a field research conduct in three technology based companies in the city of Sao Carlos. The results are presented by a characterization of each case studied, and also by a comparison between cases.
Associação de polimorfismo do gene PIT1 com características de produção de carne em bovinos da raça Canchim
(Universidade Federal de São Carlos, 2004-06-29)
Carrijo, Sônia Mara
;
Regitano, Luciana Correia de Almeida
;
https://lattes.cnpq.br/9595338480545794
The PIT1 gene codes for the pituitary transcription factor Pit-1, which is critical for the activation of the expression of prolactin and growth hormone genes, in addition to participating in the activation of PIT1 itself. The objective of the present study was to investigate the effect of HinfI polymorphism of this gene on meat production traits. The sample consisted of 509 Canchim animals born between 1998 and 2000. The sample included a traditional line (GG1) consisting of 5/8 Charolais genome breed and 3/8 of the Zebu breeds, Nelore, Guzerá and Indubrasil, and a new line (GG2) with 21/32 Charolais genome and 11/32 of the Nelore breed. The genotypes for the PIT1 gene were identified by PCR-RFLP. Genotype effect on phenotypic values for birth weight (BW), standardized weaning weight (W240) and at 12 month of age weight (W365), and on average daily weight gain to the born at weaning (GMND) and to the weaning at 12 month of age (GMD12), were analyzed by the least squares method. The results revealed significant effects of the interaction between genetic animal group and PIT1 genotype on W240, GMND and GMD12 (P < 0.05). The differences in mean least squares between genotype ( / ) and genotypes (+/+) and (+/ ) for W240 and GMND were significant in GG2 (P < 0,01 and p < 0,05, respectively), revealing superiority of the ( / ) genotype on that characters. The means for genotypes (+/+) and (+/ ), respectively at the W240 and GMND, did not differ from one another, suggesting a dominance effect of the HinfI (+) allele. The means effects of the HinfI ( ) allele indicated a positive effect of this allele on W240 and GMND, and the deviation estimates attributed to dominance showed a favorable effect of the HinfI ( ) allele on W240 and GMND of GG2 animals, when present in homozygosis in the genotypes of the individuals. The means of the genotypes in GG1 did not differ from one another. The difference in PIT1 behavior observed in the two genetic groups, however, may suggest the action of a quantitative trait locus linked to PIT1 segregating only in GG2 of the population studied, and not a direct effect of PIT1.
Determinantes da tomada de decisão sobre as atividades produtivas rurais: proposta de um modelo para a produção familiar.
(Universidade Federal de São Carlos, 2004-06-29)
Vilckas, Mariângela
;
Nantes, José Flávio Diniz
;
https://lattes.cnpq.br/1900976112613026
The family small farms represent a very important segment in the national economy since it plays an important role in food production, incoming generation and distribution and land occupation. However, this segment is characterized by an inadequate management, which commits its competitiveness. The main aim of this reasearch is to propose a practical and accessible production planning model for vegetables raising family farms, which can help them to consider internal and external factors when deciding what to produce. The methodology had four main stages: (i) interviews with families that raise vegetables from São Carlos, São Paulo, in order to identify the production systems and the planning of the production activities; (ii) working out a planning model; (iii) interviews with rural management and vegetable production specialists, to confirm factors used in the model, the weights given to each factor and the notes for the possibilities of the producer reality; (iv) correction and final mode s working out. When interviewing the producers, it was observed that they don t have many years of formal education, most of the families are led by 30 39 years old men, there is a wide participation of women in the labor and few producers have employees. Within 33 interviewed producers, 11 have decided to get specialized, producing from 1 to 5 vegetables options, specially the green ones. The producers do not have a structured methodology to make decisions, and they do not consider all the factors that may influence the decision of what they should produce. Concerning to the planning model, the considered factors in the decision were grouped in internal (natural, human, financial and technological resources) and external (demand, offer and support services), but the use of weights were adopted only with the internal factors. The interviewed specialists emphasized the importance of making the correct decision about choosing the product variety to be raised and also about getting organized through associations and cooperatives. This study is an initial reasearch , which may be used as a subsidy for other rural planning studies. Although the decision model proposed has been developed to be used by producers, it may be also useful for rural projects, cooperatives, associations and financial agents, since it proposes a methodology to analyze the products options.
Análise de herança da resistência à ferrugem da cana-de-açúcar P. melanocephala H. & P. Syd
(Universidade Federal de São Carlos, 2004-06-30)
Moura, Guilherme Lacava de
;
Giglioti, Éder Antonio
;
https://lattes.cnpq.br/4151969603820945
Sugarcane rust (Puccinia melanocephala) is a major disease distributed throught the world, causing yield losses of 50% in conducive environments. Resistance is an essential trait to control rust in commercial cultivars requiring routine tests along the selection time in breeding programs. In order to better understand the complexity and to determine the inheritance of rust resistance in brazilian sugarcane cultivars, this work analyzed eight F1 segregating populations involving 10 genotypes as parents. The resistance was polygenic where the segregation of several minor genes in each progeny was responsible for their classification in the different resistance levels from 2 to 9. Besides polygenetic resistance, the presence of major genes segregating 1:1 and 3:1 deviated the individuals to the grade 1, corresponding to complete resistance. It was observed transgressive segregation, generating resistance genotypes from susceptible-susceptible crosses. Therefore, to achieve resistant cultivars it not necessary to chose resistant parent if effective tests are used to screen susceptible genotypes during selection. It was also observed maternal effects in segregation, deviating individuals to rust resistance.
Análise genético-quantitativa da eficiência produtiva de um rebanho bovino da raça Canchim
(Universidade Federal de São Carlos, 2004-06-30)
Mello, Silvio de Paula
;
Alencar, Maurício Melo de
;
https://lattes.cnpq.br/9737816927066698
Genetic parameters for body weight at weaning (PD), at twelve months of age (P12), at first calving (PPP) and at adult age (PAD), condition score at calving (ECP) and at first calving (EPP), growth curve parameters A (asymptotic weight) and k (maturation rate), age at first calving (IPP), culling age (TPR, days in herd), number (ND10) and kilograms (QD10) of calves weaned up to ten years of age, total number (NDT) and total kilograms (QDT) of calves weaned during herd life, kilograms of calves weaned per year in herd (QTPR), and the ratios weaning weight of calf/weight of cow at calving (RPP) and weaning weight of calf/weight of cow at first calving (RPPP) of females of a Canchim (5/8 Charolais + 3/8 Zebu) beef cattle herd were estimated by Bayesian inference. The average values of heritability were 0.38 (PD), 0.40 (P12), 0.51 (PPP), 0.54 (PAD), 0.18 (ECP), 0.36 (EPP), 0.60 (A), 0.54 (k), 0.12 (IPP), 0.22 (TPR), 0.22 (ND10), 0.24 (QD10), 0.23 (NDT), 0.23 (QDT), 0.32 (QTPR), 0.16 (RPP) and 0.40 (RPPP), indicating that these traits have enough genetic variability to show response to mass selection, with the exception of IPP. The genetic correlations of TPR, ND10, QD10, NDT, QDT and QTPR with the body weights (PD, P12 and PD) suggest that selection of females based on weaning and 12-month body weights should not reduce the produtivity traits studied; however, increasing females adult body weight would reduce the number of calves weaned by the cow up to ten years of age. The genetic correlations of TPR, ND10, QD10, NDT, QDT, QTPR, PAD, A and k with IPP, PPP and EPP suggest that selection to reduce age at first calving, in general, should improve longevity and productivity traits of females, but the increase in body weight at first calving would reduce some of the productivity traits. The genetic correlations of IPP, EPP, PD and P12 with RPPP suggest that selection to reduce age at first calving should improve the productivity trait of the females.
Caracterização e diagnose molecular de Xanthomonas sp. Agente causal da falsa estria vermelha da cana-de-açúcar no Brasil
(Universidade Federal de São Carlos, 2004-06-30)
Souza, Lídia de
;
Giglioti, Éder Antonio
;
https://lattes.cnpq.br/4151969603820945
O papel dos polissacarídeos algais extracelulares na dinâmica de metais no reservatório de Barra Bonita
(Universidade Federal de São Carlos, 2004-06-30)
Gouvêa, Sandra Protter
;
Vieira, Armando Augusto Henriques
;
https://lattes.cnpq.br/4428377384377272
The influence of phytoplankton and their excreted materials in natural waters have been considered important issues among metal speciation studies. This work focused on the potential influence of the high molecular weight materials excreted by dominant phytoplankton species of Barra Bonita reservoir (Anabaena spiroides, Microcystis aeruginosa and Aulacoseira granulata) in the speciation and complexation of Cu and Cd. Therefore, this study comprised field and laboratory studies. Seasonal samplings were made during a period of two years in the reservoir. The total, ionic and organic concentrations of Cu and Cd were determined, as well as the complexation parameters with ligands present in the reservoir water. Also, the dissolved organic carbon and physico-chemical parameters of the water column were obtained. A speciation model was applied to metal complexation parameters and total metal concentrations obtained in field investigations. Laboratory cultures of the selected microalgae were made to obtain high molecular weight excreted materials. In a similar manner, the high molecular weight materials were isolated from the reservoir water. These materials were analysed for metal complexation with Cu and Cd, monosaccharide composition and elemental analysis (C, H, N and S). In the reservoir water, Cd speciation was dominated by ionic species, while Cu was mostly associated to the dissolved organic matter. Seasonal samplings presented Cu ligands with similar complexation parameters for the entire period studied. Cd complexation was not detected in the reservoir water. The speciation model resulted in similar Cu2+ concentration to the mean value obtained in field analyses, and indicated higher Cu association to the ligands of the reservoir water. Cu was complexed by all high molecular weight materials studied, while Cd was complexed solely by the cyanophyte materials. Higher proportions of acid monosaccharides in the high molecular weight materials corresponded to higher Cu and Cd complexation parameters, whereas no relation between C, H, N and S proportions and metal complexation properties of the high molecular weight materials was observed. The excreted materials of dominant microalgae from Barra Bonita reservoir had Cu ligands with intermediate to weak binding strength, as those present in the reservoir water. These results indicate the potential influence of such organic materials in metal speciation, bioavailability and mobility of metals with similar behaviour to that of Cu in the reservoir water.
A atuação do professor de matemática na educação de jovens e adultos: conhecendo a problemática.
(Universidade Federal de São Carlos, 2004-07-01)
Migliorança, Fernanda
;
Tancredi, Regina Maria Simões Puccinelli
;
https://lattes.cnpq.br/9218253421106800
The Education of Young and Adults comes gaining space in the research carried through in the educational area. A great concern exists in understanding the process of education for which passes these people, who had remained many years without schooling or moved away from the educational system. An inquiry on the practical of the professors who act on the Education of Young and Adults is important to understand this process better, once that these professionals are responsible for the learning of this population and their insertion in the educative field. The particularity of this work is in investigating how the professor of Mathematics acts on the Education of Young and Adults, searching to know better their Mathematics perceptions and its teaching and also about learning of Mathematics for this population. For this, besides observing the teaching performance of these professionals it was looked to better know them through interviews and analysis of a study of case elaborated from participants of the inquiry classrooms events. The research had three professors of Mathematics participants, who act on the Education of Young and Adults in a state public school of a country city of São Paulo, and the students of one of its classrooms. Given the participants characteristics, the research constituted in three studies of case, each one referring to a professor and its classroom. To base this study I abandoned legal supports that sustain this modality of education, about profile of this clientele, about the situation of Mathematics education for these pupils and about basic and permanent formation of the professors who act on this area. Some results of the research are showed to follow. Young and adult people initiates their studies or returns to school after many years of removal with clear intentions: they search to invest in the study, since they had not access on it in the appropriate age, trying to improve their conditions of life. Moreover, they bring back specific and previous knowledge on the return to school, that assists or not themselves in learning process. All these aspects must be recognized and valued by the professors, searching to take care of young and adults' objectives that had made them return to school. When it has reported to the searched professors, it has evidenced that the lack of specific formation to teach Mathematics to young and adult people and the diffculties found in the work environment, in the school and its context, has important influences in pedagogical practical. However, when the professors have themselves availability to analyze their practical one, they invest in the diffculties overcoming and looking for new ways, even not finding institution support. For these professors, the idea of that teaching is a solitary passage becomes stronger. Although restricted, this educational scene of Mathematics teaching for young and adult people gives some suggestions to improve formation and performance of the professionals who act on this area.
Dinâmica de coerência e decoerência de estados em redes de osciladores quânticos dissipativos
(Universidade Federal de São Carlos, 2004-07-02)
Ponte, Mickel Abreu de
;
Moussa, Miled Hassan Youssef
;
https://lattes.cnpq.br/7828776012924524
In this thesis we studied the coherence and decoherence dynamics of states in a network of dissipative quantum oscillators. The coherence dynamics refers to the swap and recurrence process of states between the oscillators composing the network. These processes become crucial to understand the decoherence dynamics of states in a network of dissipative quantum oscillators. Beyond the weak coupling regime between the oscillators, where the dissipative dynamics is ruled by the usual Liouville operators L`½1;:::;N , associated to each of the ` = 1; :::;N oscillators of the network, we also considered the strong coupling regime. In this regime, the dissipative dynamics is also ruled by cross-decay channels Lm;n½1;:::;N (m 6= n = 1; :::;N) which leads to important consequences to the coherence and decoherence dynamics of quantum states of the network. Considering a network with only two coupled dissipative oscillators, we reproduce in this system the phenomenology of the Eletromagneticaly Induced Transparency or the Dynamical Stark Effect which are typical of the radiation-matter interaction when one of the oscillators is submitted to linear or parametric amplification process, respectively.
Manejo do cálcio intracelular e influência da temperatura sobre a contratilidade cardíaca de Synbranchus marmoratus
(Universidade Federal de São Carlos, 2004-07-08)
Rocha, Matheus Lavorenti
;
Kalinin, Ana Lúcia
;
https://lattes.cnpq.br/5493936744279888
The present study anlyzed the in vivo and in vitro responses of the myocardium obtained from Synbranchus marmoratus acclimated at 25 ºC and tested at 15, 25 and 35 ºC. The in vivo heart rate (fH bpm) was measured during acute transitions in temperature and subsequent return to 25 ºC. ECG recordings (lead DI of the electrocardiography) were obtained of electrodes at cardiac region. Recordings of the isometric contraction force (Fc mN.mm-2) and time-dependent parameters (TPT time to peak tension; THR time to half relaxation) were obtainded in vitro from ventricle strips electrically paced in response to stimulation frequency, temperature, extracelular Ca2+, adrenaline and ryanodine (blocker of the sarcoplasmic reticulum SR). The species showed a significant increase in the fH during the transition from 25 to 35 ºC, and a significant decrease from 25 to 15 ºC, showing the importance of the chronotropic adjustments in response to thermal alterations and a great tolerance and adaptation to different thermal conditions. The species did show significant changes in the twitch force (Fc) development by the ventricular strips during the increases and decreases of temperature. The addition of crescent Ca2+ concentrations to the medium evidenced the importance of the extracellular Ca2+ for the heart contraction mainly at 35 ºC. Significant changes in the time-dependent parameters after increments in the Ca2+ extracellular concentration were not recorded. The post rest tension was conducted with and without 10 µM ryanodine in the medium. A significant post rest potentiation was recorded for the control preparations at 25 oC (100 to 119.8 ± 4.1 %) and 15 ºC (100 to 118.4 ± 2,8 %). However, this post rest potentiation was inhibited by ryanodine only at 25 oC (100 to 97.6 ± 1.5%), and, at 35 oC, force remained unchanged in the control preparations, but a significant post rest decay was recorded in the presence of ryanodine (100 to 76.6 ± 4.6%). The impact of increases in the imposed contraction frequency caused a decline of the force only at high frequencies in all the experimental temperatures. The maximal stimulation frequency sustained by the species is superior at high temperatures. The addition of a tonic level of adrenaline (10-8 M) did not cause any significant alteration in force or time-dependent parameters, when compared to control values. However, in presence of the 10 µM ryanodine, the Fc decreased significantly, without alteration in the TPT and THR. Additionally, the adrenaline concentration was incresed to 10-5 M. The adrenergic stimulation with high level of adrenaline caused positive inotropy with a magnitude that ameliorated the negative inotropic effect of ryanodine, with the exception of high pacing frequencies. In conclusion, S. marmoratus seems to possess large stores of intracellular activator Ca2+, resembling mammals rather than terrestrial ectothermic vertebrates. As a difference, this species also depends on extracellular sources of Ca2+ at high temperatures which provide more flexibility to modulate the contraction force.
Racismo na "família ferroviária": brancos e negros na Companhia Paulista em São Carlos.
(Universidade Federal de São Carlos, 2004-07-12)
Ferreira, Lania Stefanoni
;
Monsma, Karl Martin
This research consists in a study of the relationship between white and black employees of the Companhia Paulista de Estrada de Ferro between 1930 and 1961. The aim of this research is to understand the racial relations between these two groups, how they formed their identity in everyday work and the forms of racial discriminations. To realise this research, twenty retired laborers of Companhia Paulista who live in São Carlos were interviewed.
Utilização do método LiDS para identificação de diretrizes visando a análise de impactos ambientais no ciclo de vida de produtos veterinários.
(Universidade Federal de São Carlos, 2004-07-12)
Lucente, Adriano dos Reis
;
Nantes, José Flávio Diniz
;
https://lattes.cnpq.br/1900976112613026
Ocupação de fundos de vale em áreas urbanas. Estudo de caso: Córrego do Mineirinho, São Carlos, SP
(Universidade Federal de São Carlos, 2004-07-17)
Amorim, Lia Martucci de
;
Cordeiro, João Sergio
;
https://lattes.cnpq.br/2572864522562875
;
https://lattes.cnpq.br/0409424166730354
In the last 50 years, the Brazilian urban growth process is compromising in many ways the environmental quality of the cities. Thus, among several impacts existents, it s possible to notice an inadequate occupation of river marginal areas. This is causing modifications in the physical and biological environmental elements, wasting potential recreation areas and bringing several problems to the urban population, like inundation and flood. The purposes of this research were to investigate and discuss environmentally correct alternatives to river marginal areas occupation. There were developed environmental criteria to provide solid basis for planning the land use of these areas. Based on these criteria, an example of local characteristics evaluation method was proposed. This method was applied to the chosen object of study - Mineirinho stream marginal area - in the city of São Carlos-SP-Brazil. The main results obtained were the studied area environmental situation diagnosis and some suggestions of occupation or restoration.
Processamento e transformações de fase em ligas para armazenagem de hidrogênio processadas por moagem reativa
(Universidade Federal de São Carlos, 2004-07-20)
Santos, Sydney Ferreira
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Ishikawa, Tomaz Toshimi
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https://lattes.cnpq.br/5726055117451807
In the present work, the phase transformations in metallic materials processed by reactive milling were investigated. The as-milled samples were characterized by X-ray diffraction, transmission and scanning electron microscopy, X-ray dispersive energy spectrometry, differential scanning calorimetry and hydrogen content determination. The effect of the processing parameters on the structure, morphology, hydrogenation and contamination content were analyzed. The processed materials were a Ti33-Cr36-V31 alloy and the elemental powder mixtures Mg-50Ni and Nb-28Mg (compositions in at. %). For the Ti-Cr-V alloy, reactive milling induces the disproportionation of the original BCC solid solution phase resulting in a material composed by a mixture of vanadium hydride, hexagonal Laves phase and V-poor BCC solid solution. For the Mg-50Ni, it was observed the a higher energy mill aids the chemical and morphological homogeneity of the powders. It was also observed that initial hydrogen pressure and milling times affect both hydrogenation and phase formations. For higher times (96h) and pressures (2,0MPa of H2) of milling, it were observed evidences of a Mg-Ni-H phase disproportionation. Finally, the reactive milling of the Nb-28Mg mixture shows the catalytic effect of the Mg on the hydrogenation of this nanocomposite. After 48h milling, the Nb of the nanocomposite were almost all transformed in NbH2 and absorbed 95% of its theoretical hydrogen storage capacity. For pure Nb, processed by the same way, the phase formed was NbH and the metal absorbed only 33% of its theoretical hydrogen storage.
Estudo por espalhamento Raman dos efeitos de desordem química e estrutural no espectro de fônos do InSb indentado
(Universidade Federal de São Carlos, 2004-07-20)
Joya, Miryam Rincón
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Pizani, Paulo Sérgio
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https://lattes.cnpq.br/1038437165007849