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Comissões não remuneradas no IFSP Sertãozinho: participação dos servidores técnicos administrativos
(Universidade Federal de São Carlos, 2019-04-29) Souza, Maria Eduarda de; Mossin, Eduardo André; https://lattes.cnpq.br/5531142963166222; Pimentel, Andréa Eloisa Bueno; https://lattes.cnpq.br/9330438553830026; https://lattes.cnpq.br/9292509771336568
This paper aimed to analyze how the dynamic of the cooperation of the administrative technical servers from the Sertãozinho campus of the Federal Institute of São Paulo (IFSP) works in relation to their participation in unpaid commissions. The research was developed from the assumptions of altruism, selfishness and cooperation, since monetary issues or other incentives are unrelated. In contrast to what may happens in private institutions, in this particular case, the attendees were mostly volunteers, and end up watching their workload increase. The present work used the motivational theories to cover the theme, but the game theory was chosen as the analysis factor to carry out the research. Game uses mathematical data and economic dynamics to deal with psychological and social factors. This kind of research approach is very interesting because, in a simpler way, it can capture the "cleanest" reactions of the target audience. The work was carried out with the administrative technical servers of the Sertãozinho campus, in three stages: quantitative survey regarding the participation of each server in commissions, virtual questionnaire, and face-to-face dynamics. In all moments of the work, considering the employees collaboration in the participation of each research stage, it was possible to observe the group cooperation subject. The results analyzed provided information that may be of great importance to afford the managers with data that may influence the motivation for the participation, and also the quality of the employees in these work groups. Keywords: Cooperation. Altruism. Motivation. Theory of games.
A utilização da variabilidade da frequência cardíaca para a prescrição individualizada do intervalo de recuperação entre as sessões de treinamento de força
(Universidade Federal de São Carlos, 2019-04-29) Oliveira, Ramon Martins de; Libardi, Cleiton Augusto; https://lattes.cnpq.br/8953409094842074; https://lattes.cnpq.br/7421171937326025
The aim of the present study was to investigate if resistance training (RT), performed with individualized recovery between sessions (RT-IND), promotes greater gains in strength and muscle mass and reduces the variability on adaptations compared to RT with fixed recovery intervals (RT-FIX). Twenty young men (age 21.9 ± 3.3 years) were randomized in the RT-IND and RT-FIX groups. Five days before the beginning of the training, measurements of the root mean square of successive R-R intervals differences (RMSSD) values of each individual were performed to establish the baseline values. Before each RT session, the RMSSD values determined whether the participants from RT-IND protocol were recovered from the previous session. Participants performed the RT session only if RMSSD values had returned to the baseline, otherwise they had to wait for an additional 24 h. RT-FIX performed an RT session every 48 h. Muscle strength was measured by one-maximal repetition (1-RM) test and muscle cross-section area (CSA) of the vastus laterals by ultrasonography were assessed pre- and post-training. 1-RM values increased significantly from pre to post-training for both groups (RT-IND: 30% and RT-FIX: 42%, main time effect, P < 0001), with no significant difference between groups. Muscle CSA increased significantly from pre to post-training (RT-IND: 15.7% and RT-FIX: 15.8%, main time effect, P < 0001), with no significant difference between groups. In conclusion, RT-IND did not increase the gains in muscle strength and mass neither reduce the variability in muscle adaptations when compared to the RT-FIX.
Avaliação do desempenho do biorreator de vórtices de Taylor na expansão de células estromais mesenquimais
(Universidade Federal de São Carlos, 2019-04-29) Gil, Liseth Viviana González; Suazo, Cláudio Alberto Torres; https://lattes.cnpq.br/9591447226240450; https://lattes.cnpq.br/0402210458004107
Interest in the use of mesenchymal stromal cells (MSCs) has increased in the last 10 years because of the increasing discovery of its special characteristics for the treatment of diseases through cell therapy or tissue engineering. Despite being in the majority of postnatal organs and tissues, the amount of MSCs required to initiate any clinical treatment is insufficient and therefore the necessity of its in vitro expansion. Cultivation systems with the use of microcarriers and bioreactors, such as the stirred tank, are presented as the immediate proposal, allowing to obtain high cellular densities in a 3D environment. However, the stirred tank presents some limitations related to the distribution of hydrodynamic forces within the bioreactor and the difficulty in controlling the size of aggregates formed during cultivation, ultimately affecting the process yield of obtaining viable cells. A highly promising bioreactor proposal for presenting low and more homogeneous shear stresses, satisfactory mass transfer and ease of scaling is the Taylor Vortex Flow Bioreactor (TVFB). In a preliminary study, the BEVT, with a work volume of 60 mL, was promising in the cultivation of a line of immortalized CEMs attached to microcarriers, presenting controlled sizes of cellular aggregates (<400 μm) under conditions of low shear stresses and with sufficient oxygen transfer. In this sense, the present work involved the construction and the study of a BEVT with a work volume of 100 mL, for the cultivation of primary CEMs currently used in clinical treatments. Thus, the additional evaluation of important hydrodynamic parameters, such as the minimum velocity of suspension of particles (Ns1) and time of mixing (θm) in different conditions of rotation, were approached for two internal cylinder configurations, named in this study as round and deformed. In this evaluation the BEVT with the deformed inner cylinder presented better performance and was chosen in the culture studies. For this configuration Ns1 values between 70 and 90 rpm were obtained using a concentration of 1 to 3 g of microcarregages/mL and a maximum θm of 21±2,2 seconds for a rotation speed of 50 rpm. Cultivation of umbilical cord derived CEMs cultures and Cultispher®S 1 and 3 g / L adipose tissue using the 10% SFB alpha MEM culture medium confirmed the best modulation of the aggregation presented in the BEVT, compared to the Spinner flask, under low shear conditions, confirmed by the LDH enzyme activity, and with adequate oxygen transfer, obtaining factors of expansion of up to 17 times of viable and functional CEMs. Thus, these results present the BEVT as a very promising alternative for the cultivation of large-scale CEMs for cell therapy.
Estudo da carbonatação de concretos com adição de nanosílica
(Universidade Federal de São Carlos, 2019-04-29) Pereira, Fernando do Carmo; Ferreira, Fernanda Giannotti da Silva; https://lattes.cnpq.br/0329487394818763; https://lattes.cnpq.br/8190613301875819
The degradation of reinforcing concrete structures reflects in economic and environmental factors. Thus, the desire to minimize it motivates recent research, which aims to add nanomaterials to the cement matrix, seeking to change and improve its properties, among them durability. Nanosilica is a mineral addition with a diameter ranging from 3 to 150 nm, which interacts chemically and physically in the hydration reactions of the cement and in the microstructure of the concrete. Its use still demands knowledge regarding the effect of its incorporation in cementitious composites, such as its influence on the carbonation of the concrete. The penetration of CO2 decreases its alkalinity and generates the disassembling of the armature, which may come running in the presence of oxygen and water, compromising the durability of the structure. In this context, the present work evaluates the accelerated carbonation in concrete with nanosilica, when submitted to the attack of CO2. Traces were formulated with two different water / binder ratios, 0,40 and 0,56. The superplasticizer additive was incorporated only in concretes with water binder ratio equal to 0,40 in order to guarantee the established consistency (230 ± 10 mm). In addition to a reference trait (without mineral addition), cylindrical test specimens (50x100 mm) with different nanosilica contents (1%, 5% and 10%) were molded, as well as a trace with 1% addition of nanosilica together with 10% active silica. The accelerated carbonation tests were performed under two different conditions, a chamber with 15 ± 2% CO2 concentration, relative humidity of 75 ± 5% and temperature of 23 ± 2 °C, and another with a concentration of 3,0 ± 0,5% carbon dioxide, relative humidity 65 ± 5%, and temperature 27 ± 2 °C. In some traits, the pH of the simulated pore solution was also evaluated and microstructural pulp assays performed. The results of the mechanical strength and water absorption tests by capillarity indicate a better performance of the concretes with water/binder ratio equal to 0,40 and the trace with 10% addition of nanosilica showed to be more efficient. In the tests of durability only the specimens with water / binder ratio equal to 0,56 presented carbonation front, independent of the concentration of CO2 to which they were submitted, and there was a greater advance of the attack of CO2 in the trace with addition of 1% of nanosilica and 10% of active silica. The pH evaluation of the simulated pore solution made it possible to observe the clear difference between the values of the carbonate region and the interior of the still uncarbonated test specimen and the microstructural tests indicate a higher amount of calcium hydroxide in the reference trace. Finally, it can be concluded that in larger water/binder ratios, the effect of the porosity on the porosity of the concrete may overlap with the effect of the mineral addition of pore refinement, but the influence of these additions on the mechanical and physical properties, because in the traces with relation water/binder equal to 0,56, in spite of improving them, the addition of nanosílica damages the resistance of the concrete against the attack of CO2, due to the pozzolanic reactions that result in a lower alkaline reserve, and thus, collaborate to further advance the carbonation front.
Avaliação do comportamento de aderência entre blocos cerâmicos e grautes
(Universidade Federal de São Carlos, 2019-04-29) Sipp, Gustavo; Corrêa, Márcio Roberto Silva; https://lattes.cnpq.br/7780769246876333; Parsekian, Guilherme Aris; https://lattes.cnpq.br/7798651726059215; https://lattes.cnpq.br/3638400400620590
The behavior of structural masonry elements is influenced by the properties of the constituent materials and also by their interactions in the contact regions. The bonding properties between ceramic blocks and grouts used in masonry constitute a gap in national and international design standards. The existing knowledge in the academic world is currently insufficient to adequately describe the behavior presented by the interface of blocks and grouts. It is still unclear whether the grout is capable of adequately transferring the stresses of the reinforcement inserted into the masonry blocks. Thus, it is clear the need to deepen the studies developed to evaluate the adhesion properties between blocks and grouts. In this sense, the present study is inserted, aiming to expand the existing knowledge about the bonding behavior between ceramic blocks and grouts. In this sense, the present study is inserted, aiming to expand the existing knowledge about the bonding behavior between ceramic blocks and grouts. This research aimed to evaluate and discuss the properties that affect the adherence between 5 types of ceramic blocks and two types of grouts. The push-out test was used to evaluate the bond strength mobilized by the combination of these different materials. In addition, the pull-out test was also employed for some block types, seeking a more realistic analysis of the bonding behavior on masonry elements. The results obtained in the push test prove that there is a wide variation in the results, depending on the type of block and grout employed. Some of the main characteristics that influenced these results were the shape of the block cells and the shrinkage of the grout. The blocks that presented cells with more grooved surface and with friezes, tended to present increase in the contact area between grout and block, providing increases in the bonding stress. In the case of grout, the use of grout with higher compression resistance was responsible for the reduction in the results of the push test, precisely due to the reduction in the contact area caused by the shrinkage of the filler material. A test procedure was developed to analyze the shrinkage of the grout inside the ceramic blocks. Based on the results of the push test, an analytical model was developed considering two factors k1 and k2, responsible for considering the geometric shape of the block cell and the shrinkage of the filler material. This model allowed to roughly estimate which maximum load was mobilized in the push test for each combination of block type and grout. Finally, a numerical modeling of the identified interface properties was developed for two block types that presented grout slip during the push test. The behavior obtained was similar to that presented in the force vs sliding curves of the grout, for the tested specimens.
Análise ergonômica da atividade na execução do serviço de revestimento de gesso
(Universidade Federal de São Carlos, 2019-04-29) Almeida, Roberta Bibbó de; Paliari, José Carlos; https://lattes.cnpq.br/9387796929252598; https://lattes.cnpq.br/1259620621767093
The construction industry is an important segment of the Brazilian economy, generating a large volume of wealth and jobs for various sectors. Although over the years technological advances have occurred and many physical tasks have been replaced by mechanized and automated processes, due to the availability of construction workers at low costs most of the construction tasks are still performed manually. Work in the construction industry is among the most dangerous occupations, tasks often require excessive physical exertion or perform repetitive tasks over a long period of time, which can lead to health problems. In this context this research is inserted, through ergonomic analysis is intended to generate knowledge about the ergonomic risks that construction workers are exposed, more specifically those involved in the execution of wall and ceiling coating with plaster. To identify the ergonomic risks present the following tools were selected for the case studies: Rapid Entire Body Assessment (REBA), to analyze the postures adopted during the tasks; Occupational Repetitive Actions (OCRA); for analysis of repetitive tasks; and The standard metabolic equivalent (MET), to analyze the caloric expenditure in the activities. Through the experience with the workers, questionnaires and tools application, it was possible to understand the reality of these workers. Tool's application made possible to identify the criticality of the risks and also to identify in which stages of the production process they stand out. For the REBA tool, the tasks that showed greater criticality were the Receiving and Storage and the Coating of the lower part of the walls. The OCRA tool showed high exposure indexes in the analyzed activities, mainly for the right limb in the finishing activity on walls and ceilings. For the MET tool, the tasks that stood out with high caloric indexes were the Receiving and Storage and the Waste collection and storage.
Microestrutura, resistência mecânica e corrosão sob tensão em ligas de alumínio Al-0,3%Fe e Al-4%Cu processadas por extrusão em canal angular
(Universidade Federal de São Carlos, 2019-04-29) Braga, Diogo Pedrino; Della Rovere, Carlos Alberto; https://lattes.cnpq.br/8141224513975606; Sordi, Vitor Luiz; https://lattes.cnpq.br/8364164402481940; https://lattes.cnpq.br/8407711610386433
Grain refinement is an important hardening mechanism in metallic alloys, notably when the grain size reaches the submicrometer scale. For this purpose, several techniques of Severe Plastic Deformation (SPD) have been employed, among which is the Equal-channel Angular Pressing (ECAP). However, the relation between grain size and corrosion resistance remains a controversial subject for most metallic materials. The aim of the present work is to evaluate the microstructure, the mechanical strength and the stress corrosion cracking (SCC) resistance of two ulfrafine grained aluminum alloys, AA1050 and Al-4%Cu, severely deformed by ECAP. Microstructure was analyzed by optical microscopy (OM), scanning (SEM) and transmission (TEM) electron microscopy, while the mechanical strength was evaluated through conventional hardness and tensile tests. Constant load and slow strain rate (SSR) tensile tests were carried out in an aqueous solution containing 3.5wt% of NaCl, in order to evaluate the SCC resistance of the alloys. After ECAP, OM and MEV revealed a significant grain size reduction in both alloys, with a fragmentation and redistribution of coarse second phase particles in the case of Al-4%Cu alloy. Hardness and tensile tests indicated a remarkable increase in the mechanical strength of the processed materials. In SSR tensile tests, with a relatively short time of exposure to the NaCl environment, CST was detected only in the Al-4% Cu alloy. In constant load tests, fractures occurred at stress levels lower than the yield stress, indicating CST susceptibility for long exposure times, in both alloys. In the absence of Cu particles (AA1050), no significant effects of ECAP processing were observed on the response to CST tests. In the case of Al-4% Cu alloy, it was found that the presence, as well as size and distribution, of the second phase particles affects the CST resistance, and that these factors can be modified, and possibly controlled, by means of ECAP processing.
Manifestações patológicas em áreas molháveis em alvenaria e gesso acartonado em edifícios hotéis
(Universidade Federal de São Carlos, 2019-04-29) Francescatto, Taciane Roberta; Barreto, Douglas; https://lattes.cnpq.br/7369326190168139; https://lattes.cnpq.br/2869873782051688
Buildings that use the drywall system for internal partitioning need more care in environments with high moisture content, because the plasterboard component is sensitive to water action. Due to its application in the commercial sector and especially in the hotel sector, it is common to use plasterboard in wettable environments. Thus, there is a dichotomy between these environments and the sealing component. Thus, this research aims to present and analyze the pathological problems that occur in wettable environments of hotel buildings built with masonry walls and plasterboard. Regarding the recommendations proposed by the technical literature for the construction of plasterboard walls in wettable environments, the bibliographic research identified different constructive guidelines among the analyzed documents and, however, all are guided by NBR 15758-1 (2009), which is complemented by executive technical details provided by the manufacturers manuals. To identify the main pathological manifestations that occur in wettable environments built with drywall, a field survey was conducted involving hotels in the region of São Carlos-SP. In all, 7 hotels participated in the qualitative research through the application of quizzes, and among these, 3 participated in the quantitative research, developed from the analysis of documents of daily occurrences provided by the participants of this study. Regarding the results obtained from the application of the quizzes, it was possible to know the constructive profile of the buildings and maintenance teams of the hotel sector. Among the findings, it was found that most of the projects are built with reinforced concrete structure and masonry, with few using the drywall system for internal sealing, and in general, few have a building sector. self-maintenance and assiduous, it was found a unique responsibility, in which the team includes only one employee who is responsible for the management and for small and medium repairs. Regarding the documentary analysis, in Hotel 01 (EH1) and EH2, both with drywall, the area with the highest incidence of problems was the bathrooms, with 54% and 52% of occurrences, respectively. Already the EH3, with walls in masonry, the bedroom zone was the one with the highest number of records, with 65% of occurrences and 27% in bathrooms. Regarding the occurrences, although EH3 presents more records numerically, no significant differences were found when comparing the problems that occur in drywall seals with those in masonry. In the three hotels, the place with the most occurrence was in the sanitary installations, with 80% of the records, of which 48% refer to the detachment of objects from the wall. Finally, this research identified a set of pathological manifestations, with their characteristics and influences in the drywall system. This research was of great value and contributes to the knowledge of the real problems that occur in hotel buildings, because it is from records of occurrences that it is possible to raise more reliable studies regarding the pathological manifestations. This study has great potential to expand the knowledge of pathology in other types of buildings.
Avaliação da degradação de vigas reforçadas com FRP quando expostas ao intemperismo
(Universidade Federal de São Carlos, 2019-04-29) Ferreira, Douglas da Costa; Parsekian, Guilherme Aris; https://lattes.cnpq.br/7798651726059215; Dalfré, Gláucia Maria; https://lattes.cnpq.br/0066111999826468; https://lattes.cnpq.br/2834570840133327
Considering structures natural aging process and also considering externally strengthened elements exposure to aggressive environments (freeze-thaw cycles, temperature, carbonation, ultraviolet radiation, wet-dry cycles, among others), little is known about the behavior and durability of the strengthening system bonding to the concrete substrate and the possible performance loss due to degradation of the intervening materials. In this context, the present work is based on the experimental analysis of the long term mechanical behaviorof the constituent materials of the reinforced concrete beams with carbon fiber sheets strengthening system (CFRP, Carbon Fiber Reinforced Polymer) applied according to the EBR (Externally Bonded Reinforcement) technique kept in laboratory environment (internal and protected) and exposed to weather (external exposure). Eight reinforced concrete beams with rectangular section, longitudinal reinforcement rate of 0.75% and concrete with compressive strength of 20 MPa, were tested. Among the set of beams, four were used as reference and two were strengthened with carbon fiber sheets, and the others were divided into two groups and exposed to six-months laboratory environment and six-months weather environment. These beams, with a distance between the supports of 230 cm, were submitted to three-points flexural testing with a midspan concentrated load. The beams were designed behave in strain limits with tension controlled rupture. Beams behavior analysis was performed based on the results of the loads and modes of rupture, deformation of the intervening materials and cracks propagation. The experimental results were also compared with the estimates limits specific at ABNT NBR 6118 (2014), ACI 318 (2014) and ACI 440.2R (2017). In addition, specimens of the strengthening system materials constituents were also created and exposed to the same environmental conditions as the beams. The mechanical properties of these materials were investigated from uniaxial tensile testing. The results showed that lamination epoxy adhesives present reductions of up to 70% in their mechanical properties when exposed to the weather, while the CFRP composite showed similar properties before and after exposure. In the case of the strengthened reinforced concrete beams, it was verified that the strengthening system provides increases of 50% and 28% in the load capacity and stiffness, respectively, when compared to non-strengthened specimens. However, the tests performed after exposure to the elements showed a reduction in the increase of the load capacity. In relation to the comparison between the theoretical and experimental results, taking into account the specifications at ABNT NBR 6118 (2014), ACI 318 (2014) and ACI 440.2R (2017), it was observed that the values of ultimate load and service load are close when property reductions are not applied.