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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
;
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
;
https://lattes.cnpq.br/1038437165007849
Proposta de um middleware para monitoramento de situações de emergência em ambientes físicos ou lógicos cientes de contexto
(Universidade Federal de São Carlos, 2004-07-21)
Micheloti, Gislaine Cristina
;
Araujo, Regina Borges de
;
https://lattes.cnpq.br/8964123297688432
Ubiquitous computing in which information and services are offered to users in a continuous and non-intrusive way, is widely explored for classroom, meeting rooms, tourist guides, intelligent home and also safety-critical applications: industrial, aviation, metro-train safety, patient monitoring, etc. The advances in heterogeneous visualization and information access devices, sensors and wireless networks has propelled the emergence of applications that need fine grain monitoring to prevention, combat and evaluation of emergency situations. In the first case (prevention), information is captured from sensor network in order to prevent critical conditions. In the second case (combat), it can aid with more detailed information to help decision making in the management of rescue teams (for instance, in the localization of people and objects in environments with heavy smoke and/or flames), and, in the third case (evaluation), to help auditory for insurance companies, training teams, and even people responsible for the safety of the environment being monitored. In this work, a system for Monitoring Emergency Conditions in context aware environments is considered as being a physical or logical environment with sensors across it that capture context information, which are interpreted, recorded and visualized in 3D virtual environments that mimic the real environment. This work presents a proposal for a Middleware, which is platform and programming language independent that meets functional requirements of context aware systems, such as context interpretation, localization, adaptation, etc., as well as non-functional requirements, such as: reliability, efficiency, modularity, portability, interoperability and extensibility. The middleware is specified as a set of services that interact with the application, with a sensor network and with services themselves. The interaction is achieved through a publish/subscribe mechanism based on topics in that subscriptions and notifications are issued and described in XML, and transmitted through the SOAP protocol, making the system accessible from the web. The services can be integrated and executing in a single computer, or they can be distributed across the network and even ran in nodes of a sensor network.
Desenvolvimento de métodos para determinação de metilbrometo de homatropina em produtos farmacêuticos empregando turbidimetria em fluxo e titulação condutimétrica
(Universidade Federal de São Carlos, 2004-07-23)
Canaes, Larissa de Souza
;
Fatibello Filho, Orlando
;
https://lattes.cnpq.br/9859737944357808
Antimuscarinic compounds are drugs, which play important role on the central nervous system. The most widely used are atropine, escopolamine, homatropine and homatropine methylbromide. These drugs are utilized in several clinical situations, and, because of this, it is necessary to develop simple, fast and effective analytical procedures for the dosage of these pharmaceuticals. In this work, three procedures for the determination of homatropine methylbromide in the pharmaceuticals were described: two with turbidimetric detection, and one with condutometric detection. In the first procedure, the homatropine methylbromide (C16H21NO3.CH3Br)reacted with silicotungstic acid (H4Si(W3O10)4) forming a precipitated ([C16H21NO3.CH3]4[Si(W3O10)4](s)), which was measured at 410 nm. A volume of 125µL of the 1.0x10-3 mol L-1 silicotungstic acid solution and a sample volume of 375µL were introduced into a carrier at flow rates of 2.0 mL min-1 and 3.9 mL min-1 respectively and a tubular coiled reactor of 50 cm was used. A solution of 0.05 mol L-1 HCl was used to carry the sample and reagent solutions. The analytical curve was linear in the homatropine methylbromide concentration range from 8.1 x 10-5 to 2.2 x 10-4 mol L-1 (r=0,996), with a detection limit of 5.0 x 10-6 mol L-1 (3σB /slope). Relative standard deviations (RSD) of smaller than 1.5% were obtained for the homatropine methylbromide solutions in the concentrations of 1.08 x 10-4 and 1.62 x 10-4 mol L-1 (n=10). Recoveries ranging from 96.0 to 103.0% were obtained. This method was applied in the determination of this drug in the pharmaceuticals, with a sample throughput of 70 h-1.In the other flow injection procedure, the homatropine methylbromide (C16H21NO3.CH3Br) reacted with AgNO3 forming a precipitated AgBr(s), which was measured at 410 nm. A volume of 25µL of the 1.0x10-2 mol L-1 AgNO3 solution and a sample volume of 375µL were introduced into a carrier at flow rates of 2.0 mL min-1 and 3.9 mL min-1 respectively and a tubular coiled reactor of 50 cm was used. The analytical curve was linear in the homatropine methylbromide concentration range from 8.0 x 10-4 a 1.7 x 10-3 mol L-1 (r= 0,998), with a detection limit of 9.5 x mol L-1 10-5 (3σB /slope). Relative standard deviations (RSD) smaller than 2.0% were obtained for 1.2 x 10-3 and 1.5 x 10-3 mol L-1 homatropine methylbromide solutions (n=10). Recoveries ranging from 94.9 a 104,0% were obtained. This method was applied in the determination of this drug in the pharmaceuticals, with a sample throughput of 75 h-1. In the final condutometric procedure, 10 mL of either the sample solution or the homatropine methylbromide solution (C16H21NO3.CH3Br) was titrated with 1.0x10-3 mol L-1 AgNO3 at 200 rpm and 25°C. The LD was 1.0x10-4 mol L-1.
A reação de Diels-Alder entre p-Benzoquinonas 1,3-Pentadienos-1-Substituídos
(Universidade Federal de São Carlos, 2004-07-23)
Finelli, Fernanda Gadini
;
Brocksom, Ursula
;
https://lattes.cnpq.br/6662565980382547
In this dissertation, studies are described on the cycloaddition of 1-silyloxypentadiene- 1,3 and 1-acylamino-pentadiene-1,3 with alkylated para-benzoquinones. The first methodology involves cycloaddition reactions of dienes 51, 115 and 116, under catalysis and thermolysis conditions, with para-benzoquinones 37, 42 and 43.The second methodology involves the preparation of the diene in situ from the α,β-unsaturated aldehyde (80) and the amide (81) in the presence of the p-benzoquinones 37, 42 and 43.Theoretical calculations have been carried out on the frontier orbital energies, and the coefficients of the dienes and dienophiles employed in this work, and then compared with the experimental results. Cycloadduct 52 has been studied chemically with the objective of attaining the functionality of common eudesmane sesquiterpenes.
Efeito da fragmentação Florestal sobre borboletas (Lepidoptera, Hesperiidae) associada à formiga-de-correição Eciton burchelli (Hymenoptera, Formicidae, Ecitoninae)
(Universidade Federal de São Carlos, 2004-07-27)
Vieira, Rosamary Silva
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Dias Filho, Manoel Martins
;
https://lattes.cnpq.br/1346547036069954
Efeitos da dramatização sobre compreensão oral de histórias infantis por alunos com deficiência auditiva.
(Universidade Federal de São Carlos, 2004-07-27)
Carvalho, Vânia Lúcia Corradi
;
Mendes, Enicéia Gonçalves
The scholar integration proposal demands that the school organize itself to facilitate the access for students with hearing impairment to the curriculum, allowing them, under those circumstances, to have educational opportunities to reach enough knowledge to perform their citizenship. The educational needs of these students demand effort of educators providing them a flexibility of the instruction resources, making feasible the opportunities of learning that take into account their singularity, especially related to communication. This paper had as the main objective an assessment to evaluate the effectiveness of the use of fairy tale dramatization, as an educational strategy to provide an improvement of the oral comprehension of stories for five students with hearing impairment, aged between 7 and 13, enrolled on a public school. It was used an experimental multiple baseline design between individuals, which started with an assessment of previous knowledge that each participant had; hearing impairment, previous knowledge about the fairy tale, followed by the participation of each one in a training with a pedagogical activity and in the end a dramatization related to the fairy tale. These activities were performed by each student in different moments, in a same group composed of four no-hearing-impairment participants. The data were collected by video and/or tape recordings. One statistical descriptive analysis was applied, by comparing the previous knowledge that each student with hearing impairment had about the fairy tale, before and after the achievement of both pedagogical activities and dramatization. The results showed that the participants who had been exposed to the two posterior interventions showed more improvement in performing the assessment tests of the fairy tale oral comprehension, as much in the evaluations accomplished after the introduction of the pedagogical support activity as after the dramatization activity. Although the two interventions had promoted improvement in this performance, there were differences in the magnitude of the change when it was compared with each individual among themselves, or in the student himself, the effect of the two strategies (pedagogical support and dramatization). The inter and intra-individual rate differences suggest that individuals benefited themselves in different ways when the two teaching strategies were used, and it seems to point toward that there is no superiority of one strategy over another, what implies the importance in diversifying the teaching instruction to fulfill the individual particularities in learning condition of students with hearing impairment.
Síntese e caracterização de pós de Li2TiSiO5 e Na2TiSiO5
(Universidade Federal de São Carlos, 2004-07-30)
Albarici, Viviane Cristina
;
Leite, Edson Roberto
;
https://lattes.cnpq.br/1025598529469393
This work presents a systematic study of the synthesis and characterization of Li2TiSiO5 and Na2TiSiO5 compounds. We studied their structural, morphologic and luminescent properties using X ray diffraction, Raman spectroscopy and scanning electron microscopy. These materials have in their crystalline structures centers of pentacoordinated titanium. The samples were produced through two different synthetic routes, both based on Pechini method. Different heat treatments were applied in order to obtain crystalline and disordered materials. The polymeric resins obtained were submitted to Raman spectroscopy, to verify their influence on the different routes used in the powders preparation. These materials were analyzed by X ray diffraction and Raman spectroscopy, to study the thermal evolution of the phases, as well as the structural disorder of the samples. Rietveld refinement were performed on the diffraction patterns of the crystalline samples. The morphology of the samples was investigated by scanning electron microscopy. After structural characterization, luminescent properties of the synthesized powders were studied. These studies were realized using excitation wavelengths of 250 and 488nm. The obtained results showed that Li2TiSiO5 did not present luminescent properties when the excitement wavelength was 250nm but they did when disordered and excited by the 488nm line. On the other hand Na2TiSiO5 samples presented luminescence with excitement of 250nm although didn t present this property when excited with 488nm. For a better understanding of the luminescent properties in the Li2TiSiO5 and Na2TiSiO5 compounds, their electronic structures were investigated by quantum-mechanical studies. This investigation allowed us obtain information about the effects of deformations in the crystalline structure and in the physical properties of these compounds. The obtained results suggest that the luminescent properties can occur by different mechanisms and thus depend on the crystalline structure and the excitement wavelength.
Do "barro de loiça" à "loiça de barro": caracterização etnopedológica de um artesanato camponês no Agreste Paraibano
(Universidade Federal de São Carlos, 2004-07-30)
Alves, Ângelo Guiseppe Chaves
;
Marques, José Geraldo Wanderley
;
https://lattes.cnpq.br/7962059488333070
Ethnopedological studies have been devoted mainly to agriculture, paying little attention to other aspects (e.g. pottery) of land use. The main objective of this work was to describe and analyse local knowledge and practices among peasant potters, as related to some soils that they use as ceramic resource, in a rural village (Chã da Pia) in Northeast Brazil. Peasant soil knowledge was described and analysed through an adaptation of classic ethnoscientific techniques, attempting to articulate emic and etic data, following Marques s Comprehensive Ethnoecology. Five soil profiles were formally described by researchers (etic approach) near pits where local people obtain pottery clay. Later, peasant artisans where asked to indicate the soil categories or materials they recognized in those same soil profiles (emic approach). Samples collected during both emic and etic approaches were used to describe and analyse the soils existing near these clay sources. Peasant potters recognized variations between the topsoil and subsurface soil. They were capable of distinguishing, identifying and naming, their way, some soil materials arranged in layers ( capas ) along the soil profile: terra (earth), piçarro (gravel), cabeça do barro (clay head), barro de loiça (ceramic clay), and pedra mole (soft rock). The multi-layered arrangement of these materials along the soil profiles was similar to the arrangement of the horizons as described in formal pedology. Nonetheless, local potters did not seem to know about pedogenetic relationships among these layers. Discriminant-canonical analysis, based on chemical, physical and morphological soil features, has shown clear distinctions between the agricultural topsoil and subsurface layers from where ceramic resources may be collected. It also made possible to demonstrate physical, chemical and morphological similarity among some soil materials (as distinguished by local potters) and the pedogenetic horizons where these materials are normally found. Barro de loiça is the main ceramic resource obtained from local soils. It was found mainly as part of the the 2Bt horizon in Eutric Planosols and Haplic Solonetz. The making of ethnopedological studies in different social and pedological environments could be an aid to the advancement of formal soil knowledge, also giving an opportunity to understanding and valuing local soil knowledge and management.
Influência do ambiente construído na distribuição das temperaturas do ar em Araraquara/SP
(Universidade Federal de São Carlos, 2004-07-30)
Barbugli, Renata Aboud
;
Roriz, Maurício
;
https://lattes.cnpq.br/6355579765506588
The central theme of this dissertation was to evaluate the influence of the urban occupation in the variations of air temperature in Araraquara, a medium size city in the central region of the State of Sao Paulo. At first, temperature takings were made in places that are representative of the different tipologies of urban occupation in the city and the first results showed temperature variations up to 6oC in different places. Besides the measurements made in each of the places, some of the theoretically physical determining parameters of temperature variation were registered, such as: altitude, solar rays incidence angle at noon, roof area, vicinity to water, number of inhabitants per square meter and the percentage of paved, cemented, trees and grass areas. The quantification of the urban occupation design parameters was obtained through topographic maps and serial color orthophotography of the city area. Using the Cluster statistical analysis, the different places were put together according to the similarities of its urban occupation design parameters. Then, for each of the groups, multiple linear regression analyses were made to relate the thermal parameters to the quantified urban occupation parameters. These analyses allowed the elaboration of representative thermal maps of the typical summer and winter days. The observation of the maps showed significant differences between the urban perimeter and the intensely inhabited areas. The least thermal densities were observed in places of higher urban density, demonstrating, then, the occurrence of the urban thermal inertia.
Estrutura genética das populações de abelhas africanizadas (Apis mellifera L.) da Colômbia estimada através de marcadores nucleares e mitocondriais
(Universidade Federal de São Carlos, 2004-07-30)
Quiroga, Carlos Fernando Prada
;
Del Lama, Marco Antonio
;
https://lattes.cnpq.br/7198095288825585
In 1957 a hybridization process occurred in South America between European and African bees just introduced in the continent. Since the arrival of the Africanized bees to Colombia in 1978 and their total establishment four years later, there have been done few studies about the degree of hybridization between Africanized swarms from Brazil and the resident ones. Allozymic analysis showed that: I) Hk-1 and Mdh-1 allele frequencies in Colombian Apis mellifera samples are very similar to the ones of Brazilian bees; ii) Africanized populations from Colombia have different levels of introgression of African genes into the European genome of the resident bees; iii) these populations are at Hardy-Wienberg equilibrium and the loci are not at linkage disequilibrium, suggesting that the Africanization process of the Colombian bees has been completed probability; iv) the presence of a altitudinal clinal variation suggests an effect of natural selection on Mdh-1 phenotypes. The 16S region of the mitochondrial DNA showed almost exclusively the African pattern of Colombian bees, a result similar to that was found in Brazilian and Uruguayan bees. The increasing frequencies of haplotype A1 (C/A) for the intergenic region CO I CO II of Colombian bees is related to the decrease of the pattern A4 (B/B) during the movement of the Africanized swarms from Brazil to north of the continent. Based on the results for the three regions of the mitochondrial DNA (16S, intergenic region CO I - COII and CO I), a high number of haplotypes was observed, showing the heterogeneous maternal origin of these colonies. These mitochondrial DNA haplotypes are not distributed through a latitudinal or altitudinal clines indicating that the colonies with African mitochondrial DNA is able to explore many different environments in Colombia. Microsatéllite analysis showed the presence of 7 to 12 alleles for the A43 and RJP57-1 loci. The allele sizes varied between 125-150 pb and 400-600pb, respectively. The results of the present work suggest that the bee populations of Colombia are genetically similar to the ones from north Brazil based on the results from nuclear and mitochondrial markers.
Tipos de personalidade e estilos de aprendizagem: proposições para o ensino de engenharia.
(Universidade Federal de São Carlos, 2004-07-30)
Kuri, Nidia Pavan
;
Truzzi, Oswaldo Mário Serra
;
https://lattes.cnpq.br/5005536921435787
The main purpose of this study is to evaluate how the teaching of engineering can benefit from knowledge of the students personality types and learning styles. To identify the types and styles, two inventories were used, based on Jung s Theory of Psychological Types Keirsey s Temperament Sorter and Felder & Soloman s Index of Learning Styles, both translated into Portuguese. These instruments were submitted to 840 undergraduate students of Engineering enrolled in a five-years regular course at a public education institution located in the interior of the state of São Paulo. The sample was divided into four groups and three subgroups, comprising undergraduate students of Mechanical, Electrical, Civil and Industrial Engineering in their first, third and fifth years, respectively. In the statistical analyses of the results, three approaches were considered: a descriptive analysis, a correlation analysis, and a logistic model. The latter approach was introduced into the statistical analysis of the results in order to verify not only the existence of a correlative structure among the variables analyzed personality types and learning styles but also the probability of the variables qualification and undergraduate year influencing the percentage of responses obtained from the questions of the instruments. The validity of the model was proven in this study. In addition to the statistical analyses, the results were also analyzed qualitatively to discuss the possible effects of the students personality traits on their learning styles and to propose teaching-learning strategies tailored to the profiles identified, aiming to contribute to the teaching practices in engineering. The study have confirmed the reliability and validity of the instruments applied, which have been able to estimate the preferences of the population under investigation. Is also highlighted the fact that the knowledge of the student s personality traits and learning styles may have important implications for teaching. Hence, it may aid the lecturer in different ways, such as: for planning teaching/learning activities, for removing communication barriers in the classroom, for improving personal relationships, and for avoiding productivity losses.
Estudo da influência da adição de compostos de boro na resistência à oxidação de refratários a base de carbeto de silício-liga de nitreto.
(Universidade Federal de São Carlos, 2004-08-06)
Rodrigues, Cesar Augusto Frasson
;
Morelli, Márcio Raymundo
;
https://lattes.cnpq.br/0172837599844991
In this work, boron was added in a commercial silicon carbide bonded silicon nitride refractory and its influence has been evaluated. These materials have been used as high temperature structural ceramic due to their properties combination, as the hot modulus of rupture, abrasion resistance, excellent thermal conductivity, good thermal shock resistance and good corrosion resistance. To prepare the studied compositions, boron compounds were added during mixing stage and sintered at 1450o C in a nitrogen atmosphere. Some compositions were tested on a first stage using hot modulus of rupture tests and X ray diffractions. On a second stage, modulus of rupture at room temperature, scanning electronic microscopy and mainly oxidation tests (980 and 1230o C / 200 hours) were performed and valued. The obtained results were compared with the commercial refractory. As the weight gain is an oxidation indicative, samples made with boron nitride have indicated trends to be a good alternative to increase the oxidation resistance. Besides, boron additives contributed to crystallize the silica film in the samples and contributed to getting a better oxidation resistance. The oxygen diffusivity is bigger in the vitreous silica than in the crystalline, and due to this crystallization, boron additives have shown a good opportunity to decrease the oxidation rate. The results obtained by SEM showed silicon nitride fibers, mainly inside the porous. Moreover, as informed on the paper references, boron has contributed to form air bubbles in the silica film, but without bubbles rupture. These ruptures could be responsible to increase the oxidation rate in the silicon carbide surfaces. Also, spherulits were not observed in the oxidized film.
Filmes finos de LaNiO3 depositados sobre substratos monocristalinos pelo método dos precursores poliméricos
(Universidade Federal de São Carlos, 2004-08-06)
Mambrini, Giovanni Pimenta
;
Varela, José Arana
;
https://lattes.cnpq.br/1807399214239200
;
https://lattes.cnpq.br/7723027354150918
This work reports a systematic study on the deposition and characterization of LaNiO3 thin films. This material is a ceramic conductor and presents a near metallic behavior, and is interesting for capacitor electrodes application in memories systems, because of the reduction of fatigue behavior. The synthesis of the precursor resin was realized by the polymeric precursor method. The films were deposited with the spin-coating technique on five different substrates: Si(100), Safire(0001), MgO(100), LaAlO3(100) and SrTiO3(100), and after they were crystallized at 700ºC for two hours in a conventional furnace or at 700ºC for ten minutes in a microwave oven. After that, the films were characterized by X ray diffraction, scanning electron microscopy, atomic force microscopy and measurements of electrical resistivity as a function of temperature. The films deposited on Si(100) were tested as electrodes for SrTiO3 capacitors, deposited with the same method. Polycrystalline and single phase LaNiO3 thin films were obtained on Si(100), Safire(0001) and MgO(100) substrates, whereas the films deposited on LaAlO3(100) and SrTiO3(100) substrates were epitaxial. The method enable a good thickness control and allows the deposition of films without cracks and very homogeneous. Electrical measurements shown a metallic behavior between 20 and 300K, and the epitaxial films have a smaller electrical resistivity, in comparison with the polycrystalline ones. The best result was obtained with the deposition on strontium titanate substrate and the measured resistivity was 250µΩcm, lower than that obtained with others methods reported in the literature. The crystallization in a microwave oven was not so satisfactory, since films with higher resistivity than that crystallized in conventional furnaces were obtained, because their morphology. However, these films are still good for an application in capacitors systems. The system Au/SrTiO3/LaNiO3/Si(100) was also studied being the lanthanum nickelate a good electrode for this system. Dielectric constant of 250 at 10 kHz was obtained which is about the same reported in the literature for this system with Pt electrodes. Dielectric constant measurements as a function of the applied potential of work shown an asymmetric behavior because the difference between the two electrodes of the capacitor. The charge imprisonment in the ceramic/electrode interface causes a reduction in the capacitance with applied potential. In this manner, a simple methodology for preparation of thin films was used resulting in good characteristics and promising for application in DRAM systems. THIN FILMS DEPOSITED ON SINGLE CRYSTAL SUBSTRATES BY THE POLIMERIC PRECURSOR METHOD: This work reports a systematic study on the deposition and characterization of LaNiO3 thin films. This material is a ceramic conductor and presents a near metallic behavior, and is interesting for capacitor electrodes application in memories systems, because of the reduction of fatigue behavior. The synthesis of the precursor resin was realized by the polymeric precursor method. The films were deposited with the spin-coating technique on five different substrates: Si(100), Safire(0001), MgO(100), LaAlO3(100) and SrTiO3(100), and after they were crystallized at 700ºC for two hours in a conventional furnace or at 700ºC for ten minutes in a microwave oven. After that, the films were characterized by X ray diffraction, scanning electron microscopy, atomic force microscopy and measurements of electrical resistivity as a function of temperature. The films deposited on Si(100) were tested as electrodes for SrTiO3 capacitors, deposited with the same method. Polycrystalline and single phase LaNiO3 thin films were obtained on Si(100), Safire(0001) and MgO(100) substrates, whereas the films deposited on LaAlO3(100) and SrTiO3(100) substrates were epitaxial. The method enable a good thickness control and allows the deposition of films without cracks and very homogeneous. Electrical measurements shown a metallic behavior between 20 and 300K, and the epitaxial films have a smaller electrical resistivity, in comparison with the polycrystalline ones. The best result was obtained with the deposition on strontium titanate substrate and the measured resistivity was 250µΩcm, lower than that obtained with others methods reported in the literature. The crystallization in a microwave oven was not so satisfactory, since films with higher resistivity than that crystallized in conventional furnaces were obtained, because their morphology. However, these films are still good for an application in capacitors systems. The system Au/SrTiO3/LaNiO3/Si(100) was also studied being the lanthanum nickelate a good electrode for this system. Dielectric constant of 250 at 10 kHz was obtained which is about the same reported in the literature for this system with Pt electrodes. Dielectric constant measurements as a function of the applied potential of work shown an asymmetric behavior because the difference between the two electrodes of the capacitor. The charge imprisonment in the ceramic/electrode interface causes a reduction in the capacitance with applied potential. In this manner, a simple methodology for preparation of thin films was used resulting in good characteristics and promising for application in DRAM systems.