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Propriedades de transporte eletrônico em filmes de diamante crescidos por deposição de vapores químicos
(Universidade Federal de São Carlos, 2007-02-27) Berengue, Olivia Maria; Chiquito, Adenilson José; https://lattes.cnpq.br/7087360072774314; https://lattes.cnpq.br/1312983845888585
In this work it was investigated some fundamental properties of undoped and Borondoped (p-type) synthetic diamond films. It was investigated the influence of the cleaning process on the surface s quality in order to produce better metal-diamond electrical contacts. Two cleaning processes were used: chemical and physical (thermal treatment). The Raman spectroscopy was used as a fundamental tool in order to quantify the changes in the samples surfaces after both treatments. It was observed an increase of the resistivity, and consequently a decrease of the superficial conductivity. This fact was related to non-diamond layers remotion being confirmed by current-voltage measurements. These curves show the Space Charge Limited Currents (SCLC) as the dominant conduction process in the samples revealing the expected insulator character of the undoped films. It was also investigated the presence of charge localization eﬀects (due to the presence of deep levels) using the admittance spectroscopy. It was found two impurity centers with activation energies around 34-74 meV and 340-360 meV. They are related to the activation of non-Boron deep levels and Boron acceptors, respectively. The most important conclusion in this case is that the presence of these levels suggests diﬀerent conduction mechanisms acting on the samples; this hypothesis was confirmed by temperature dependent resistivity measurements. Moreover, it was confirmed the hopping process as the dominant conduction mechanism in a large range of temperatures. Additionally, it was determined the spatial extension of the wave function associated to the carriers. All these previous data on the transport mechanisms in diamond films have motivated the development of a device which was primarily designed to be used as a temperature sensor. Characteristics such as sensibility, resolution and time response were well determined. The device presented a reliable behavior and good reproducibility even under influence of external parameters like light and magnetic fields.
Ciências sociais e secularização: um estudo sobre a trajetoria de vida religiosa de profissionais formados em ciências sociais na Paraíba
(Universidade Federal de São Carlos, 2007-02-27) Alves, Edvaldo Carvalho; Lima, Jacob Carlos; https://lattes.cnpq.br/9244132532446607; https://lattes.cnpq.br/3942210361822168
This paper is an approach to the debate on the possible existence of an elective affinity between the study of Social Sciences and the macro-process of secularization. Secularization here is understood as the gradual, non-linear, historically and geographically determined loss of the comprehensiveness of religious discourse, which is expressed, among other factors, by the separation and autonomization of the social spheres and the consequent privatization of religion. To achieve such a goal, a group of Social Scientists from the state of Paraíba, graduated between 1980 and 2005, were chosen as the empirical space of analysis. By means of in-depth interviews their life histories were recovered with a focus on their religious views and practices before, during and after their studies as social scientists, while an attempt was conducted to apprehend by which means this process was able to change their views and practices towards secularization. By analyzing the content of the interviews, it was possible to conclude that there is an elective affinity relationship between the study of Social Sciences and secularization. This occurs because the study of the discipline, even tough it does not contribute directly to the construction of an atheist or agnostic view, it does offer the tools required for the constitution of a secular consciousness, where religion is perceived as a discourse that responds to individual needs and interests, a matter of personal choice, that means, religion is viewed and experienced by the Social Scientists analyzed, as a discourse, in modern times, that has its meaning given by the soteriological function it performs.
Efeito agudo e crônico do exercício resistido de alta intensidade sobre o torque, atividade eletromiográfica do vasto lateral e freqüência cardíaca de homens idosos
(Universidade Federal de São Carlos, 2007-02-27) Quitério, Robison José; Catai, Aparecida Maria; https://lattes.cnpq.br/5542826131682238
The objective of this study was to investigate the acute and chronic effects of high intensity resistance physical exercise on the magnitude of maximal average torque response normalized by body mass (MAT), RMS amplitude of eletromyographic signals (EMGs) of the vastus lateralis and heart rate variation (∆HR). Subjects were nine non-smoking men (ages 61.7+1.7 years, weight 72.5+6.5 Kg., height 1.69+0.06 meters) with an active lifestyle, who did not use medications or any type of drug, and were evaluated as healthy by laboratory tests and clinical examination. The experimental protocol was carried out with the volunteer in seated position with hip flexed at 85º in a computerized isokinetic dynamometer (Biodex Multi Joint System III) and consisted of 6 tests of maximal voluntary contraction (MVC): 10 sec. of isometric knee flexion at 30º (IEx) and isometric extension at 60º (IF); 5 MVC concentric of the knee at 60º/s (C60) and 8 at 120º/s (C120); 5 MVC eccentric of the knee at 60º/sec. (E60) and 8 at 120º/sec. (E120). The values for MAT were normalized for body mass (N.m/Kg). EMGs of the vastus lateralis were registered; RMS amplitude values of eletromyographic signals were calculated and then normalized for RMS of MVC isometric knee extension at 60o. HR was recorded beat to beat in bpm for 60 seconds at rest, during tests and for 120s during recuperation, by a one-channel heart monitor (TC 500 ECAFIX), interfaced to a microcomputer (PC-AT 486 DX-4) by an analogdigital converter (Lab.PC + National Instruments, Co.). The volunteers were monitored at modified MC5 derivation. For the variables studied (MAT, EMGs and HR), the mean of 3 repetitions of each test was calculated for later statistical analysis. At an intensity of 70-80% of MVC, the volunteers performed 2-4 series of 8-12 repetitions of eccentric resistance exercises in twice weekly sessions at angular velocity of 60º/s for three months. The intensity was corrected from fortnightly evaluations of the torque peak. At the end of the training period the same ones were revalued. The MAT eccentric was similar to the isometric and both were superior to the concentric in both flexion and extension. The MAT in C60 was greater than C120 for flexion and extension. The RMS of the concentric tests were superior to the eccentric (P<0,05). The ∆HR (heart rate variation) for the isometric tests was smaller than those for the dynamic (P<0,05). After training was verified: significant increase of MAT eccentric at 60o/s and 120o/s for flexion and extensior; increase in RMS at IEx, C60Ex, E60Ex e E120Ex; ∆HR was greater in the concentric tests at 120o/s and eccentric at 60o/s. The data suggest that: greater MAT and lower EMG values during eccentric exercise, when compared to values obtained during concentric contractions, may be attributed to an additional contribution of passive elastic components to the greater force during eccentric contractions; the ∆HR depends on the mechanics of the exercise (static or dynamic) and is independent of torque level, magnitude of muscular activation and angular velocity during short duration exercise; after resistance training only MAT adaptations were observed to be mode specific as no such adaptations occurred in relation to EMGs and ∆HR.
Avaliação de um programa de práticas educativas para monitoras de um abrigo infantil
(Universidade Federal de São Carlos, 2007-02-27) Prada, Cynthia Granja; Williams, Lúcia Cavalcanti de Albuquerque; https://lattes.cnpq.br/6962646759651464; https://lattes.cnpq.br/8182466634045005
In the last few decades, it seems to be increasing the number of families who find difficulties to educate its children. The most frequent parents concerns are: the difficulty of establishing limits to the behavior of the child or adolescent; how to develop behaviors that they believe to be right; and how to proceed when behaviors problems appears. These difficulties do not restrict to the universe of the families who take care of its own children, but they are also focus of concern on institutions that foster care children victims of domestic violence and those caregivers. The lack of preparation of parents, educators or caregivers of institutions, many times may develop or aggravate problems of development and behavior of these children. For this reason, this study had the aim to develop, implement and evaluate a program of intervention with caregivers that work with sheltered children who had been victims of domestic violence, in order to present a reference on Educative practices, preventing or reducing possible behavior problems of these children. To evaluate the effectiveness of the intervention program, evaluations had been applied before the beginning (pre-test) of the intervention program and soon after its ending (postest), using the following instruments: IEP - Inventory of Educative Practices, CBCL - Child Behavior Checklist and the Script of interview of life and professional background of the caregivers. Also were collected continuous measures of the Interaction between the caregivers and the children in 19 sessions, defined as 3 of base line, 12 taken three days after each Intervention session and 4 of follow-up, applied five months after the ending of the intervention. The results demonstrated a significant reduction of the negative educative practices, mainly in Relaxed Disciplines and Negative Monitoring, with high scores at the pre-test, as well an increase of the positive educative practices. The evaluation using the CBCL demonstrated that the children had presented statistical significant behavior improvement. The continuous measures data had indicated an increase of positive interaction behaviors between caregivers and children, as well a reduction of negative interaction behaviors, and the most significant outcome was that the measured frequencies of good behaviors in follow-up sessions did not return to the measured levels of the base line. The considered intervention program presented can be considered efficient to generate changes in the interaction standards between caregivers and children; however it would need to be applied in different institutions to assure the applicability in distinct environments.
Avaliação do estado nutricional, tolerância ao exercício e desempenho muscular em pacientes com doença pulmonar obstrutiva crônica
(Universidade Federal de São Carlos, 2007-02-27) Silva, Karina Rabelo da; Jamami, Maurício; https://lattes.cnpq.br/4274129560250050; https://lattes.cnpq.br/4560829479271231
Chronic obstructive pulmonary disease (COPD) is characterized by abnormal inflammation of the lungs in response to inhalation of noxious particles or toxic gases, especially cigarette smoke. COPD presents several systemic effects including nutritional depletion and musculoskeletal dysfunction that cause reduction in exercise tolerance. The aim of this study was evaluate the functional capacity and performance of the respiratory and peripheral muscles and relate them to nutritional status and FEV1. Methods: 12 patients with moderate-severe COPD (70±7 years, FEV1 52±17 % predict, BMI 23±4 kg/m2) and 7 healthy volunteers (69±8 years, FEV1 127±12% predict, BMI 27±3 kg/m2). All of them performed body composition analysis, measuring of maximal respiratory pressure (PImax and PEmax), a symptom-limited cardiopulmonary exercise test (TECR), evaluation of upper limbs force, peak torque and total work of the quadriceps femoral. Results: Patients with COPD had lower values of free-fat mass (FFM) index (18±1 versus 21±1 kg/m2, p≤0,05), maximal load in the TECR (60±20 versus 102±18 watts, p≤0,01), PImax (58±19 versus 87±21 cmH2O, p≤0,05), upper limb force (38±6 versus 47±5 kg, p≤0,05), peak torque (103±21 versus 138±18 N.m, p≤0,05) and total work of the quadriceps femoral (1570±395 versus 2333±568 J, p≤0,05) when compared with control group (test t-Student non-paired). It wasn t found correlation between FEV1 and the variables studied, and FFM index was correlated with the total work of the quadriceps (Pearson, r= 0,6290, p≤0,05). Conclusion: This results point to that patients with COPD show weakness of the inspiratory and peripheral muscles and a reduced functional capacity compared to a ix healthy group. Besides, it suggests that airflow limitation is not a good predictor to quantify nutritional and muscular debilities of patients with COPD.
Efeito do envelhecimento e da dose energética na fotobiomodulação laser de baixa intensidade na regeneração tendínea
(Universidade Federal de São Carlos, 2007-02-27) Taciro, Charles; Parizotto, Nivaldo Antonio; https://lattes.cnpq.br/5527703735628408; https://lattes.cnpq.br/8381515141542572
There is a rapid increase in the size of the elderly population due to a complex interaction of medical and epidemiological factors. Also, there is a parallel increase in morbidity associated with age-related delayed tendinopathy healing, and treatment of such acute and chronic condition costs the Health Services over 1 Billion dollars per year. Despite the obvious clinical impact, the basic cellular and molecular mechanisms underlying impaired human tendon healing are largely unknown. However, recent reports have showed the action mechanism of low level laser therapy (LLLT) in producing accelerated tendon healing, but the real effects of this therapy associated with aging effects are not yet known. This study evaluated the effects of the LLLT on repair process of rat calcaneal tendon in two different ages. Eighty male Wistar rats were divided in 2 experimental groups with 40 rats at each one: young group (4 weeks old, body mass = 111.3±34,3g) and mature adult group (27 weeks old, body mass = 385.4±34,3g). The young group was subdivided in subgroup Y3J (12 session, total energy = 101.7mJ, laser 685nm, 5.4W/cm2, 3J/cm2), subgroup Y10J (12 session, total energy = 339.6mJ, laser 685nm, 5.4W/cm2, 10J/cm2); subgroup YPL (placebo treatment) and subgroup YCL (no treatment). The mature adult group was subdivided in subgroup A3J (12 session, total energy = 101.7mJ, laser 685nm, 5.4W/cm2, 3J/cm2), subgroup A10J (12 session, total energy = 339.6mJ, laser 685nm, 5.4W/cm2, 10J/cm2); subgroup APL (placebo treatment) and subgroup ACL (no treatment). All animals had the medial region of right calcaneal tendon totally tenotomized. They were sacrified on the 13th post-operate day and their tendons were surgically removed for a quantitative and qualitative analysis The Atomic Force Microscopy analysis showed better organization quality (alignment, thickness and aggregation) of collagen bounds in mature irradiated groups. However, it was found differences (p < 0.05) in thickness of collagen bundles (TCBs) for several intersections among subgroups. The subgroup A10J presented greatest TCBs (5.69±0.69), and the ACL subgroup presented smallest TCBs (4.51±0.6) in the mature group. The dimensional data showed higher differences in the irradiated subgroup in mature group when compared to the same subgroup in young group. Histological analysis showed increase (p < 0.05) in the number of capillar vessels and fibroblast cell proliferation after LLLT in both young and mature groups, however the higher modulation was observed in the mature group. Minor influence of laser radiation in the young group may be justified by divergence on chemistry, physics and metabolic age-related. Maybe the accumulated oxidative stress resulting from a gradual shift in the redox status of tissues should be a key mechanism underlying the aging process and the higher laser effect noted in the mature group. Age should be considerated an important parameter to LLLT.
Influência da propaganda nos hábitos alimentares: análise de conteúdo de comerciais de alimentos da televisão
(Universidade Federal de São Carlos, 2007-02-27) Santos, Silvana Lopes dos; Batalha, Mario Otávio; https://lattes.cnpq.br/1015001063418091; https://lattes.cnpq.br/1643423784795201
Food advertising and it effect on the food choices has been the target of frequent debates, being attributed to a great part of the responsibility for the problems of bad feeding of the population. Such situation has led to government initiatives with the aim to discipline the food advertising, mainly those destined to children. These initiatives can have important consequences on the promotion strategies of the food sector. The present work had as main objective to investigate the frequency and content of the food commercials on television, considering the strategies adopted in relation to the characteristics of the message, the food, the consumer and the appeals, as well as the execution or not of ethical norms of advertising. Therefore, the programming of three open TV channels was recorded during the morning, afternoon and night at preestablished schedules and then used in the content analysis. The results pointed to the prevalence of food commercials in the morning mainly for children advertising mostly products rich in sugar and fat. It was verified that the messages are fundamentally affectionate, with emphasis on the flavor of the food and the pleasure with little reference to the nutritional aspects and health. Great part of the commercials also presented debatable elements regarding to the ethics. At the end of the work, considerations are made about the need of the analysis of the food choice in a wider context, considering the advertising just one of the influence variables. It is considered that only joint actions of the public and private sector are capable to aid in the promotion of healthier food habits.
Perspectivas a um manejo sustentável subsidiado pela ecologia humana : o caso da captura do caranguejo-uçá, Ucides cordatus no município de Cananéia - SP - Brasil
(Universidade Federal de São Carlos, 2007-02-27) Jankowsky, Mayra; Nordi, Nivaldo; https://lattes.cnpq.br/8168865557947289; https://lattes.cnpq.br/9106050537260893
The sustainable management should be the principal objective of any proposal to regulate and to use natural resources. Based on concepts of ecodevelopment and viable development, the present research evaluated sustainability of mangrove crab fishing, Ucides cordatus, in municipality of Cananéia, at south of the State of São Paulo, Brazil; and its management possibilities. Procedures were open interviews, semi-structured interviewing, directly observing, informal colloquies and followed trips. Production and measures of crabs captured by traditional technique completed the research data. Results evaluation included as qualitative analysis (property rights and management practices) as well quantitative analysis (RAPFISH method). The history shows this fishing activity as secular and for subsistence, inserted in market during the 70 decade, and now a days adopting two conflicting methods: arming and small net . There is a large local knowledge about abiotics, biotics and supernatural aspects concerning mangrove crab fishing; but the approach is different between arming and small net fishermen. The results shows that to reach the sustainability it is necessary to manage the resource focusing social and economics aspects, creating or fortifying the local institutions, and proposing feedback mechanisms; to have a more dynamic and more effective regulation for the mangrove crab fishing.
Estudo da dinâmica de portadores em diodos de tunelamento ressonante tipo-p
(Universidade Federal de São Carlos, 2007-02-27) Galeti, Helder Vinicius Avanço; Gobato, Yara Galvão; https://lattes.cnpq.br/7558531056409406; https://lattes.cnpq.br/3876752605313288
Photoluminescence spectroscopy has been used to provide important insight on the tunneling dynamics of carriers in double barrier diodes. In this work, we have performed time-resolved photoluminescence measurements in symmetric and asymmetric p-type GaAs/AlAs resonant tunneling diodes in order to study the tunneling dynamics of photocreated minority electrons. We observed several peaks in the current voltage characteristics (I-V) associated to the resonant tunneling of holes through different quantum well heavy- and light-hole sub-bands. Under light excitation, we have observed the developing of additional peaks in the I-V curve. For the asymmetric structure, two peaks were observed and associated to the exciton assisted tunneling and resonant tunneling of photogenerated electrons. We have studied the temporal evolution of the GaAs contact and quantum well (QW) emission versus the applied bias voltage. For the QW, the luminescence comes solely from the recombination between the lowest-energy confined levels in the QW even when the device is biased at higher tunneling resonance peaks. For both structure, the PL decay depends on the applied voltage and presents a bi-exponential decay for some values of bias. The results revealed a markedly long PL decay at the bias voltage associated the exciton assisted tunneling resonance in the current voltage characteristic. For the GaAs emission, we observed a weak dependence of the PL intensity versus voltage and a mono-exponential decay. We analyze our results considering the diffusion and tunneling of minority electrons in the structure
Condições de trabalho, produtividade e riscos à saúde do trabalhador na atividade do corte manual de cana: um estudo de caso na Usina Santa Adélia
(Universidade Federal de São Carlos, 2007-02-27) Valença, Vanessa; Alves, Francisco José da Costa; https://lattes.cnpq.br/9183120186518337; https://lattes.cnpq.br/4962600004543160
The present research aimed understanding three variables existents in the manual sugar cane cut activity: workforce conditions, productivity and risks to the worker s health. To reach this objective it was necessary to observe, by the descriptive research, a serie of factors like the workforce conditions necessary to the rurals historical evolutions; the actual workforce conditions existent in this activity; the productivity reached in the activity; the workers health risk in the sugar cane cut activity; and under the research on field method, a case study that could show the the three variables working in a plant, which conclusion presents several visions taken by this variables comprehension.
Conversas sobre ensino médio, reformas, alunos e professores : a difícil arte do encontro
(Universidade Federal de São Carlos, 2007-02-27) Abdalla, Vilma; Abramowicz, Anete; https://lattes.cnpq.br/5795828483983162
This study carried through in school of average education, in city of average transport, of the São Paulo interior. It looks for to understand the faced difficulties, from the optics of the professors. As cloth of deep we have the intended reform of average education and the project of qualification on service and in long-distance, entitled Average Education in Net. By means of the professors speech, at a moment of particular difficulty of the school where was gave the research, it is intended to register and to understand the strikes, the lines of removal and the lines of confluence which is established between the official speech of the reformators and of the presumptions of the implementors of the reform proposal. In way to the questionings, professors interpret and reinterpret, they argue and they rediscuss, they construct, they desconstruct and they reconstruct the knowledge on what they understand to be the best form to fulfill what they judge to be their social paper. It is treated to cartography a conversational process as form to unite colloquy and action. Reflections based on theoretical references of Michel Foucault look for to understand the relations among the Subject, To be/To know, To be/Power, Power/To know, and To be/myself . To the end, the researcher considers the foucaultian idea on the Friendship, that applied in the educative field, it could give origin to new ethics of being together between professors and pupils, capable to reduce the inevitable relations of Power to a minimum amount of domain, a pedagogical contract that would rescue the school while public space, although the relations of Power, where a new way to teach and to learn could be reinvented.
Formação de pesquisadores na UFSCar e na área de Educação Especial: impacto do programa de iniciação científica do CNPq
(Universidade Federal de São Carlos, 2007-02-27) Cabrero, Rodrigo de Castro; Costa, Maria da Piedade Resende da; https://lattes.cnpq.br/2515882021813934
ABSTRACT The investments in Science and Technology have improved the quality of life. Researches dealing with persons with special educational needs had extended the knowledge about this population group and had supported the development of instructional strategies. However, it is necessary to increase the national scientific community to nourish new knowledge. The research shows the influence of the Institutional Scholarship Program for Undergraduate Students - PIBIC of the National Council for Scientific and Technological Development - CNPq, to breed the future generation of scientists in the Federal University of São Carlos - UFSCar and in the area of Special Education. The study evaluates the Science and Technology in Brazil and discusses the formation of a new generation of scientists. The research approach includes a general study examining Special Education in Brazil and an evaluation of advances coming from theses and dissertations in this area. The first study deals with the academic trajectory of former PIBIC students at UFSCar and their enrollments in graduate programs encompassing Master and Doctorate degrees. The research was done by searching each previous PIBIC student by name in the institutional homepage of the Coordination of Formation of Staff of Superior Level CAPES which contains information about everyone who had finished a Master and Doctorate degrees. The time period from 1992 to 2000 was searched. Additionally, the Lattes Curricula Vitae Database was checked for update information. These data allow to evaluate the results of the PIBIC in the UFSCar based on graduate studies concluded by former students and the institution that they had chosen to continue their academic life. The second investigation covered the period of August,1993 to July, 2004, and involved around 175,000 PIBIC Scholarships granted in different regions of Brazil. The focus was to find out scientific projects related to Special Education. A classification was generated taking into account the target population and the volume of research carried out in each institution. Afterwards, CAPES and CNPq databases was checked for verification of the academic trajectory after finishing undergraduate studies of the former PIBIC students that became involved with projects in Special Education area. Around 50% of the former PIBIC students at UFSCar started graduate courses and preferred to stay in São Paulo State. Only 0.64% of the projects with analysis conditions (145.028) fits the Special Education area. General studies are in the first position, followed by the analyses about mental deficiency and, finally, hearing impairments. The estimative is that at least 36% of the former PIBIC students will conclude graduate programs encompassing Master and Doctorate degrees. It is necessary to stimulate researches and design strategies to form new researchers in Special Education area. Further studies about PIBIC scholarships are highly recommended for a better understanding of their output.
Efeitos de spin em diodos de tunelamento ressonante não-magnéticos tipo-n
(Universidade Federal de São Carlos, 2007-02-27) Santos, Lara Fernandes dos; Gobato, Yara Galvão; https://lattes.cnpq.br/7558531056409406; https://lattes.cnpq.br/1971364294897798
In this work, we have investigated spin polarization effects in asymmetric ntype resonant tunneling diodes (RTDs). When subjected to an external magnetic field parallel to the tunnel current, the Zeeman effect leads to the spin splitting of confined levels in the structure. The spin-dependent carrier injection on the asymmetric diode was investigated by measuring the left-and right-circularly polarized light emission intensities from the quantum well (QW) and contact layers as a function of the applied voltage. Under illumination, we observed distinct peaks in the current-voltage characteristics associated to the resonant tunneling of photoinduced holes and electrons through confined levels in the QW. The optical polarization and the spin splitting of the QW emission present a strong dependence on both the laser excitation intensity and the applied bias voltage. Depending on the laser excitation conditions, we have observed a signal inversion of the circular polarization from the QW. We have also evidenced the formation of a spin polarized two dimensional electron gas in the ntype contact. The results show that non-magnetic n-type RTDs can be used as voltagecontrolled spin filters for the development of spintronic devices.
Propriedades mecânicas de tração e impacto dos aços inoxidáveis CA15 e CA6NM
(Universidade Federal de São Carlos, 2007-02-27) Paula, Luiz Cláudio Araújo de; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037
The subject of this work was to study the mechanical properties, based in tensile and impact tests, of two stainless martensitic steels cast under designations of ASTM Standards, namely the CA15 steel, a steel with 12% of Cr, and the CA6NM steel, a steel with 12% Cr and 4% Ni. For both steel grades bar tests were machined out from Keel Block coupons test cast in sand molds bonded with no-bake resin, according to the ASTM designations. Before machining the Keel Blocks were heat treated according to the ASTM standards as following: solubilization, quenching and tempering. The effectiveness of the heat treatments and the results of the mechanical tests were evaluated by means of microstructural characterization using optical and scanning electron microscopies. The CA15 steel showed the presence of delta ferrite in the martensitic matrix, and a weak tendency to carbide precipitation. On the other hand, the CA6NM steel showed predominantly a martensitic structure and strong carbide precipitation. The effect of two quenching conditions, namely water and air, were investigated on the mechanical properties of CA15 and CA6NM steels and showed to be high significance. For both steels two distinct levels of tensile strength at room temperature were obtained, one inferior to 700MPa, and other superior around the 900MPa. In the CA15 grades were obtained higher values of area reduction and lower elongation values, when compared to the CA6NM grade. The tensile tests at higher temperature (500°C), led to a reduction of approximately 30% in the values of tensile strength for the CA15 steel. However, in the CA6NM steel, the reduction of the tensile strength was lower( less than 20%) due to presence of massive carbide precipitation. After impact tests at several temperatures for determination of the ductile-fragile transition temperature, according to the 20,6J criterion, the CA15 steel revealed a transition temperature beyond 10°C, while the CA6NM steel revealed values between -100 and -150°C.
Processo de produção e processo de trabalho na cultura do café: uma comparação entre café commodity e café especial do Sul de Minas Gerais.
(Universidade Federal de São Carlos, 2007-02-27) Sanchez, Alda Maria Napolitano; Alves, Francisco José da Costa; https://lattes.cnpq.br/9183120186518337
The main objective of the present work is to verify life and work conditions of the workers of the commodity coffee cultivation and of the special coffee in the South of Minas Gerais, a region representing approximately 50% of Brazil s coffee production. Coffee cultivation has been considered as one of the most important agricultures since the end of the XVIII century, subsequently Brazil maintains a ranking as the largest coffee producer in the world. Besides financial transactions in coffee agrobusiness, it can be considered that coffee cultivation is among the farming areas that most employs workmanship in agricultural lands, preceded by cereal crops, sugar cane and citrus fruits (orange). Since 2000, coffee cultivation yields have not been favorable to the Brazilian producers, that being the case, a discussion has begun on the need to increase these revenues and on opening consumer markets for Brazilian coffee. With this in mind, a value aggregation pursuit for coffee has become today s focal point. The research carried out in the producing farms addressed the coffee production processes as well as the work process. This investigation enabled to perceive the existing differences in the production processes and also in the work processes amid the farms. By detailing each of the activities and investigating the existing work relationships in the varying coffee productions, it was observed that the special coffee plantations demand a great deal more work to perform their labor in order to assure quality coffee, on the other hand, they improve the worker s life and work conditions, especially in view of the fact that the special coffee producers need to meet the demands of the international market for their coffee to be accepted, and it is through this correlation that the worker is benefited.
Estudos funcionais de uma possível cisteíno protease de Xanthomonas axonopodis pv. citri
(Universidade Federal de São Carlos, 2007-02-27) Santos, Guilherme Rodrigo Reis Monteiro dos; Silva, Flávio Henrique da; https://lattes.cnpq.br/1757309852446263; https://lattes.cnpq.br/9985571149294322
Cysteine proteases are enzymes found in many organisms and are characterized by the presence of cysteine residue in their active site. These proteases play an important role in the organism metabolism. In pathogenic organisms, for example, cysteine proteases may be involved in the pathogenicity process by unbalancing of the biological functions of the host (biochemical and physiological regulation). Since they are involved in several diseases, these enzymes have been considered of great interest for many researchers. The current work aims to express in E. coli a recombinant form of an ORF XAC2853 predicted to be a cysteine protease by annotation of the genome of Xanthomonas axonopodis pv citri. This bacterium is responsible for citrus canker, an infection affecting citrus species which can be evidenced by superficial lesions and early fall of leaves and fruits, thus resulting in significant losses to world agriculture. After expression, the protein was purified by nickel column affinity chromatography and inclusion body solubilization, inasmuch as this protein is almost fully insoluble. The purified protein was used to investigate the activity against such synthetic substrates as Z-FR-MCA and Z-RR-MCA, and no proteolytic activity was found. However, studies in vivo using clones of E. coli expressing the recombinant protein evidenced proteolytic activity against casein. In an attempt to demonstrate the involvement of this probable protease in the pathogenicity of Xac, the knockout of the cromossomal gene in Xac was performed. A mutant having the disrupted gene was obtained and characterized. The assays of the mutant growth, when compared with the wild strain, indicate that the cysteine protease may be involved in the pathogenicity of Xac, since the inactivation of its gene by the transposon insertion resulted in a less virulent strain. In this sense, this protein may be a promising target for the combat of citrus canker.
Física no ensino médio e estudantes trabalhadores: buscando relações entre significado e sentido para a aprendizagem.
(Universidade Federal de São Carlos, 2007-02-27) Toti, Frederico Augusto; Pierson, Alice Helena Campos; https://lattes.cnpq.br/5154949759339458
According to the report of the Inter-American Bank of Development (BID) of 2000 and data from the National Secondary Education Examination (ENEM) of 2003, it is a necessity for the majority of Brazilian students who attend secondary school to conciliate studies and work. This reality can be a challenge for these students regarding their attendance and progress in school but on the other hand it can provide new conceptual horizons and perspectives that are favourable for the fusion of knowledge that is originated from the work practice and systematised knowledge learned in school. This fusion can mean new learning opportunities both in school and in the workplace, better progress in school and it can also show us possible ways of overcoming the dichotomy between theory and practice. Considering these potentialities in the face of the necessity of development of contents which are more linked to the reality of the Physics teaching, this research tried to relate fragments of knowledge in Physics which are present in the professional activities of the students to the knowledge in Physics which are typically addressed in secondary education. In order to do the research, a questionnaire was devised and it offered us a distribution of the students who work and study at secondary schools at night in Araraquara SP. Later these worker students were interviewed and their workplaces visited with the purpose of identifying fragments of knowledge of Physics present in their work activities and the personal sense students attribute to the school knowledge. A classroom research was also done in order to evaluate the students receptivity to an approach of Physics that take into consideration common elements from their work activities. The contribution of cultural-historical psychology, in particular the Cultural-Historical Activity Theory (LEONTIEV, 1978a) made possible an analysis that take into account the psychological elements that are involved in the human activities which gives grounds for the importance of creating conditions for the students to relate the personal purpose they attribute to the scientific knowledge learned at school and its social meaning. The results suggest that connexions between the Physics knowledge present in the students professional activities and that taught in school have the potential for the creation of new learning needs and this way worker students may attribute new personal sense to the learning of Physics.