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Precoating: uma alternativa mais econômica para melhorar a performance dos meios filtrantes em filtros de mangas da indústria siderúrgica
(Universidade Federal de São Carlos, 2021-04-16)
Melo, Bruna Râmela de
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Aguiar, Mônica Lopes
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https://lattes.cnpq.br/0431688649128529
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https://lattes.cnpq.br/5154217480265293
The emission of particulate matter into the atmosphere is a concern because of its environmental and human health impacts. Among the equipment used in the control of particulate material, the bag filter stands out, with a collection efficiency of up to 99.9%. There are several filter media on the market and choosing them is a challenge. Most of them, when new, have low collection efficiency, so it is necessary to carry out surface treatments to obtain a better performance. However, this surface treatment increases the pressure drop and the cost of the filter. Thus, investigating techniques with lower cost, such as precoating, presents a promising alternative to reduce the operational costs of bag filters. This technique consists of coating the fabric with a particulate material to initiate surface filtration. For its efficient use, it is necessary to know the ideal mass of precoat material and which characteristics guarantee a high filtration efficiency. Therefore, the present work evaluated the performance of different precoating powders in bag filters in the filtration of steelworks powder. For this investigation, two precoat powders (limestone and diatomaceous earth) were evaluated and different masses of materials were deposited on the filter media (PE, PE/PTFE Resin, and PE/Epitropic), which were evaluated for the collection efficiency of micro and nanoparticles, porosity of precoating and mass retained after the cleaning pulse. The results were compared with a filter coated with a PTFE membrane (PE/PTFE). The characterizations of particulate materials (particle size distribution, density, shape, and circularity) and filter media (porosity, average fiber diameter, permeability, and thickness) were carried out to understand the characteristics that impact the performance of the coating. The first filtration cycle for filter media with and without precoating was also evaluated. PEa part/PTFE showed collection efficiency above 94% for micro and nanoparticles. The other filters even showed values above 60% for microparticles collection efficiency and values above 20% for nanoparticles. By the addition of precoating, there was an increase in these values, which varied according to the coating mass deposited on the filters, with efficiencies from 80% for microparticles, to results higher than that found for PE/PTFE for both precoat powders. For nanoparticles, efficiency results were obtained with precoat from 45%, but only with diatomaceous earth, it was possible to obtain a higher value than the membrane filter. Diatomaceous earth, due to its smaller volumetric diameter compared to limestone, filled the pores of the fabric more quickly, resulting in a faster increase in pressure drop, a more compact coating, with a porosity 2x greater than that obtained for limestone and better performance in collection efficiency. About the results of retained coating mass after the cleaning pulse, values obtained for limestone were below 10% and were below 40% for diatomaceous earth. Precoating, in the first filtration cycle, did not impact the cycle time but increased the retained mass and the residual pressure drop. However, these values were lower than those obtained by PE/PTFE. In this way, precoating, for presenting a good performance in the collection efficiency in filters of lower cost, compared to PE/PTFE, is a good alternative to reduce spending on bag filters.
Envolvimento da neurotransmissão do fator liberador de corticotrofina no hipotálamo lateral na função barorreflexa em ratos
(Universidade Federal de São Carlos, 2021-04-16)
Reis-Silva, Lilian Liz
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Crestani, Carlos Cesar
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https://lattes.cnpq.br/1117432571971568
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https://lattes.cnpq.br/7287035124858172
The lateral hypothalamus (LH) is a diencephalic structure that has been considered part of the central circuitry regulating the baroreflex function. However, the local neurochemical mechanisms involved in baroreflex control by this hypothalamic area are poorly understood. Therefore, in the present study we investigated the role of corticotropin-releasing factor (CRF) neurotransmission within the LH acting via local CRF1 and CRF2 receptors in cardiac baroreflex responses in unanesthetized rats. For this, the baroreflex activity was assessed using two approaches: i) the pharmacological approach via intravenous infusion of vasoactive agents, and ii) the sequence analysis technique that evaluates reflex responses during spontaneous arterial pressure variations. The sequence analysis technique indicated that LH treatment with the selective CRF1 receptor antagonist CP376395 decreased the baroreflex effectiveness index, whereas the selective CRF2 receptor antagonist antisauvagine-30 increased the reflex shortening of pulse interval during spontaneous arterial pressure decreases. However, the pharmacological approach did not indicate effect of the bilateral microinjection of either CP376395 or antisauvagine-30 into the LH in the tachycardia evoked by blood pressure decrease or the reflex bradycardia caused by blood pressure increase. Overall, these findings indicate that CRF neurotransmission within the LH controls baroreflex function during a narrow range of physiological arterial pressure variations, but without affecting reflex responses during pronounced arterial pressure changes. Besides, results provide evidence that CRF1 and CRF2 receptors in the LH oppositely modulate the spontaneous baroreflex activity through different mechanisms.
Resistência "knockdown" em mosquitos Aedes aegypti no Brasil e suas implicações no controle da dengue
(Universidade Federal de São Carlos, 2021-04-16)
Santos, Débora Naiara dos
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Medeiros, Ane Hackbart de
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https://lattes.cnpq.br/6315858319851377
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https://lattes.cnpq.br/3204735052706758
Dengue is an arbovirus that, since its introduction, represents a great problematic for world public health, mainly in Brazil, which presents a great difficulty in eradicating this disease. Its main vector, Aedes aegypti (Linnaeus, 1762), was disseminated to several locations, through the expansion of population by globalization, successfully adapting to the environment. The climatic conditions and the lack of commitment of the population collaborate for the great mosquito population growth and for the large number of reported cases. The rate of continuous growth over the years has consequently generate high costs for the economy. The absence of vaccines and the fast dengue transmission cycle make to control vector the most viable option to combat this disease. The National Dengue Control Program (PNCD) is a project implemented by the Federal Government that institutes strategies to prevent this disease, with chemical control as one of the main control methods. By frequent use of insecticides, mainly pyrethroids, which work by opening continued in the sodium and potassium channel (CNa) characterizing a period of hyperexcitation, followed by the death of the target pest, has generated pressure for the selection of mosquitoes resistant to this mechanism of action, a phenomenon known as “knockdown” resistance, in which there is an alteration in the amino acids that make up the protein chains present in CNa that do not allow the usual action of these insecticides, consequently reducing their effect on the body. This scenario of resistance is already present in all Brazilian regions, making the Vector Control Program, which have a preference for traditional methods, a real failure. With this, the present work, of literature review, has as objective provide information on the current scenario of Dengue in Brazil and the knockdown resistance to in order to guide new projects to curb the spread of this disease in the country.
Efeito da polinização cruzada no número de sementes dos frutos de tangor Murcott Olé RBC 01
(Universidade Federal de São Carlos, 2021-04-16)
Campagnollo, Matheus Pozzobom
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Azevedo, Fernando Alves
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https://lattes.cnpq.br/0574692206149746
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Conceição, Patrícia Marluci da
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https://lattes.cnpq.br/6623193710607120
The Murcott Olé RBC 01 tangor, resulting from the Murcott Olé RBC irradiation process, shows potential as a table fruit due to its visual aspect, presenting an intense color, small-medium size, and a lower number of seeds per fruit compared to other varieties. . The objective of this work was to study the influence of pollination on the number of seeds in Murcott Olé RBC 01 fruits. The experiment was set up and conducted in the greenhouses of Citrograf Mudas in Ipeúna / SP and the analyzes made in the laboratory of the Centro de Citriculture Sylvio Moreira / SP. Adult Murcott Olé RBC 01 tangor plants were used in pots isolated from other pollinating varieties. The experimental design was randomized blocks, with three replications. Seven treatments were installed where pollens were collected from different varieties: Tangor pollen W Murcott (Verona); pollen of clementine Nules; Valencia orange pollen; tangelo pollen Nova; orange pollen Pear; Murcott Olé RBC 01 tangor pollen and Absence of pollination. A pollen grain viability test was carried out (in vitro pollen germination method). For extraction of pollen grains, large and young closed flower buds were collected, these were kept in Petri dishes with filter paper and kept at 30ºC, for 24 hours, for ripening of the pollen grains. When the Murcott Olé RBC 01 tangor plants were in full bloom, treatments were installed. Evaluations of fruit fixation, number of seeds per fruit and physical-chemical analysis of the fruits were carried out. All treatments proved to be suitable for setting. Fruit fixation was between 19 and 30%, with no statistical difference between treatments. There was no difference in fruit mass and diameter. There was a greater number of seeds in the fruits of the Murcott Olé RBC 01 tangor pollinated with W Murcott tangor pollen. The treatments with the lowest number of seeds were pollination with Murcott Olé RBC 01 tangor, followed by treatment without pollination. There were no significant differences between treatments regarding the analysis of juice yield, acidity, soluble solids and ratio. It is concluded that the fruits of the pollination treatments with Murcott Olé RBC 01 and the absence of pollination presented the lowest number of seeds, showing that the pollen itself and the absence of pollination provide such a characteristic.
Ferramentas para licenciamento paramétrico de projetos de empreendimentos habitacionais de interesse social
(Universidade Federal de São Carlos, 2021-04-16)
Maselli, Luccas Zambon
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Masiero, Érico
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https://lattes.cnpq.br/2691827106518167
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https://lattes.cnpq.br/1449105586018745
Technical standards and legislation constitute and regulate part of the housing development licensing process. Checking the conformity of new real estate projects against the legal reference values is a complex task. In this sense, the automation of this process, using computational resources, has the potential to make it more efficient. The automated compliance checking, digitally implemented, is a possible way to assist in the agility of licensing of housing developments, ensuring efficiency, objectivity, and transparency. Still, public procedures that include popular participation are ineffective and have a low adhesion rate by civil society. This dissertation aims to develop computational tools that help verify the legal parameters involved in the licensing procedures for housing developments. The proposals are divided into two fronts, aimed at popular participation and verifying requirements in geospatial models. For this, a consultative tool was developed for the population, using the Python language, in addition to a plugin for Geographic Information Systems (GIS) platform, where both are responsible for the parametric verification of housing developments. For application purposes, the city of São Carlos (SP – Brazil), and the urbanistic parameters present in its Master Plan, were used. The tool developed for public consultation operates from the insertion of primary project data, frequently found in Neighborhood Impact Studies, allowing the calculation of the coefficients applicable to the licensing process and generating a structured report of conformities and non-conformities. The geospatial tool, in turn, operates from the zoning and project’s vectorial data, and automatically calculates the applicable urban coefficients, comparing them with the reference values, where, in the end, it also generates a structured report. The application of such tools represents a breakthrough in fields that are still not very efficient, such as the popular participation in decision making and the housing licensing process itself, in addition to areas that have not been much explored, such as parametric verification on the GIS platform. The application of the tools can represent new paradigms in urban planning models since many operations performed manually can be rethought based on computational concepts. Also, the tools can integrate civil society into decision-making processes about the city and allow geospatial analysis based on the implementation of new housing developments.
O estágio como possibilidade de pesquisa na licenciatura em Pedagogia e a teoria dos campos conceituais de Gérard Vergnaud
(Universidade Federal de São Carlos, 2021-04-16)
Baima, Jéssica de Godoi
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Ciríaco, Klinger Teodoro
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https://lattes.cnpq.br/2947929641568853
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https://lattes.cnpq.br/9039695661507637
We seek to analyze the internship as a research possibility based on the experience of the first author in her degree in Pedagogy. The production of the data in question had, as its motto, reflections arising from an intervention, under the qualitative approach in education, in the 3rd year in which the Theory of Conceptual Fields by Gérard Vergnaud was the theoretical-methodological reference for the work with problem solving. Given the reality experienced, we conclude that this plays a fundamental role in the training of teachers, since it provided, in the case researched, processes of resignification of knowledge "of" and "about" Mathematical Education, as well as to know the reality of work in school and for paths of professional identity.
Associação de pré-diabetes com marcadores precoces de lesão cardiovascular
(Universidade Federal de São Carlos, 2021-04-16)
Firmino, Stella Maris
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Leal, Ângela Merice de Oliveira
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https://lattes.cnpq.br/7202663545989206
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Roscani, Meliza Goi
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https://lattes.cnpq.br/1298051150234135
Introduction: Diabetes mellitus type 2 (DM2) is responsible for about 90% of diabetes cases and its mortality is associated with micro and macrovascular complications. Individuals who are at a higher risk of developing DM2 are called prediabetics (PD). It is estimated that approximately 25% of individuals with PD will develop DM2 in three to five years. It is not yet clear in the literature how is the cardiovascular function of these patients. It is believed that there are early markers of cardiac and endothelial dysfunction in this population and that they may be associated with impaired quality of life. Objectives: To assess the presence of early markers of impairment in endothelial and cardiovascular function in PD patients compared to normoglycemic individuals and to investigate if there is an association of these markers with worsening of the quality of life. Methods: Cross-sectional clinical study with the composition of two groups: Prediabetics (PD): who met the criteria for PD and are not on hypoglycemic medication; and Normoglycemic Control (NG): who do not meet the criteria for DM and PD. Patients in both groups had no known cardiovascular disease. They underwent clinical and physical evaluation, echocardiogram, evaluation of carotid intima-media thickness (CIMT), evaluation of arterial stiffness (AR) through pulse wave velocity (PWV), SF-36 quality of life questionnaire, and sedentary lifestyle IPAQ questionnaire. Statistical analysis: comparison of groups using the Chi-square test for categorical variables, T Student test for variables with normal distribution and Man-Whitney for variables with non-normal distribution. Associations between variables in the same group were assessed by linear regression. Results: The groups were homogeneous in relation to baseline and clinical variables. In the PD group, a greater association with dyslipidemia (p<0.001) was observed, in addition to early signs of diastolic dysfunction assessed by the E wave velocity of the Mitral flow E (E (cm/s): NG 84.08 ± 13.56 vs PD 77.70 ± 11.82, p = 0.03) and greater RA (VOP (m/s): NG 7.16 ± 1.54 vs PD 7.92 ± 1.75, p = 0.04). In the linear regression model, the presence of impaired glucose tolerance was an independent factor associated with the E wave of the Mitral flow, even adjusting for confounding variables (p = 0.02). There was more prevalence of right ventricle diastolic dysfunction, regarding to E/A ratio of Tricuspid Inflow (p = 0.03) and E’ Tricuspid of Tissue Doppler (p = 0.04). The PD group also showed greater impairment in quality of life in functional capacity (p = 0.03), pain (p = 0.03), vitality (p = 0.03) dominoes and also a higher degree of sedentary lifestyle by the IPAQ score (p = 0.006). Glucose intolerance was associated with a higher degree of physical inactivity. Conclusion: PD individuals, compared to NG patients of similar age and sex, already have early markers of cardiac and endothelial dysfunction, in addition to greater impairment in quality of life. Decreased glucose tolerance, despite the association with other risk factors, such as dyslipidemia and physical inactivity, is an independent factor associated with thereductio of E mitral wave velocity.
Detecção de câncer de próstata em imagens de microscopia utilizando grafos de contexto glandular
(Universidade Federal de São Carlos, 2021-04-19)
Mendes, Rodrigo de Paula
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Comin, Cesar Henrique
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https://lattes.cnpq.br/9563440403120931
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https://lattes.cnpq.br/0502007001258822
Every year a large part of the male population is affected by Prostate Cancer (PCa), with many cases of deaths occurring especially in men over 40 years old. PCa is a pervasive condition that diffuses and manifests itself in a wide range of histological patterns, which can be visualized with details in histological images acquire through biopsy or prostatectomy. Early detection of PCa can improve the prognosis and reduce the risk of death. Currently, the main methodology for the diagnosis of PCa consists of a qualitative analysis carried out by specialists to define the degree of the disease in the so-called Gleason Grading System(GGS), originally defined by Donald Gleason and refined by the International Society of Urological Pathology. Given the importance of identifying abnormal prostate tissue (staging) to improve the prognosis, many computerized methodologies have been developed to assist pathologists in a systematic way for the diagnosis. It is often argued that an improved diagnosis of a tissue region can be obtained by considering measures that take into account various properties of the tissue surroundings, henceforth referred as the context of the tissue. Such a context is considered an important biological factor in staging. This work proposes a new methodology that can be used to systematically define contextual features related to prostate glands. The Gland Context Network (GCN) structure is defined, which is a representation of the prostate sample containing information about the spatial relationship between the glands as well as the similarity between their appearance. It is shown that the GCN can be used to establish contextual features at any spatial scale. Therefore, information that is not easily defined from traditional features can be easily extracted using the proposed approach. In addition, it is identified that even basic properties derived from a GCN can lead to state-of-the-art classification performance in relation to PCa. All in all, GCNs can assist in defining the most effective approaches for PCa detection.
Efeito do teor de titânio no endurecimento por precipitação em uma liga à base de Co-Ni e consequências nas propriedades mecânicas
(Universidade Federal de São Carlos, 2021-04-19)
Miura, Leonardo Hideki
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Jorge Júnior, Alberto Moreira
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https://lattes.cnpq.br/6360362248108490
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https://orcid.org/0000-0002-8121-9834
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https://lattes.cnpq.br/2215712604237709
The alloy subject of this study, designated by the Unified Numbering System, R30035 and internationally known as MP35N®, is a 35 Ni – 33.5 Co – 20.5 Cr – 9.5 Mo alloy with very-high mechanical strength, ductility, and corrosion resistance. Therefore, it is commonly found under extreme conditions in aerospace, medical, motorsport and petrochemical industry components. Due to this wide range of applications, there are different international standards and specifications for the alloy, which define limits on mechanical properties, or specific ranges of chemical composition for the amplification of some particular property, whether mechanical resistance or corrosion. Changes in the chemical composition have greater potential for altering the alloy's further processing. Specifically, the restrictions of the maximum titanium content in 0.1% compared to the usual 1.0%, in some applications, lead to drastic changes in the plastic behavior of the material, and, in its solidification process, observed in this work. To study the effects of this variation on the chemical composition of the alloy, on the mechanical properties, ingots were produced on a pilot scale in a VIM furnace, which were subsequently hot-formed, solubilized and cold-worked. The basic mechanical properties of the materials were evaluated through tensile, hardness and Charpy-V impact tests at room temperature, after aging in the laboratory. The main difference was the material ductility variation associated with the presence of titanium carbides.
Aspectos termodinâmicos e cinéticos do uso de plugues porosos para a remoção de partículas cerâmicas por bolhas inteligentes
(Universidade Federal de São Carlos, 2021-04-19)
Falsetti, Luís Otávio Zaparoli
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Ferreira Muche, Dereck Nills
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https://lattes.cnpq.br/6542991023278848
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Pandolfelli, Victor Carlos
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https://lattes.cnpq.br/7369376873984839
Non-metallic inclusions can spoil the mechanical properties of the steel depending on their composition, geometry, size and distribution. In this context, “inclusion engineering” is a rising area in steelmaking industry which studies the modification and removal of ceramic particles from the molten steel. Among the likely tools to withdraw these inclusions, the generation of bubbles through purging plugs shows the advantage of allowing the high productivity demanded by the continuous casting. This process comprises the generation of bubbles, their expansion throughout the ladle, the capture of the ceramic particle and their transfer to the slag phase. Thus, understanding the fundamentals involved in each step is of great importance to master the bubbling in ladles aiming cleaner steels. The present work studied the current practice of steel cleaning using bubbles, analysing the size limits to the capture of ceramic particles and discussing alternatives to obtain cleaner steels. Besides, the infiltration of liquid metal into the porous structure was analysed to minimize the plug maintenance due to clogged metal. Therefore, computational calculations were carried out based on mathematical models for each step of purging plug practice, and the results were validated by comparison with physical simulations from the literature and the industrial practice.
Development of stable and high-performance polyaniline activated carbon electrodes for capacitive deionization desalination
(Universidade Federal de São Carlos, 2021-04-19)
Barcelos, Kamilla Malverdi
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Ruotolo, Luís Augusto Martins
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https://lattes.cnpq.br/6167735734348703
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https://lattes.cnpq.br/4285214258496042
Capacitive deionization (CDI) emerged as a cost-effective alternative for the desalination of brackish water (salt concentration lower than 10 g L−1). Significant progress in electrode materials in terms of salt adsorption capacity (SAC) and charge efficiency (QE) has been performed in the last few years. However, there are still challenging issues concerning the improvements of the adsorption/desorption kinetics and the electrode stability for long-term operation. In this sense, the main goal of this thesis was the development of stable electrodes of polyaniline (PAni)-activated carbons (PAC) for long-term desalination, with optimized electrosorption/desorption kinetics. The comparison between blade-casting (DB) and free-standing (FS) electrodes of p-toluenesulfonate-doped PAC (PAC/PTS) showed the effects of electrode interparticle porosity and thickness on their textural and electrochemical properties and enabled a better understanding of how tuning the preparation technique of the CDI electrodes can improve the desalination performance, especially in terms of adsorption/desorption kinetics. Although the different electrodes perform similarly in terms of gravimetric salt adsorption capacities, FS electrodes outperform the DB electrodes in terms of volumetric salt adsorption capacities. These carbon films were more compact, and a large quantity of electroactive material was available for salt adsorption. Therefore, if the material cost is not a limitation, the maximum amount of salt could be removed using compact CDI cells with FS electrodes. On the other hand, when the electrosorption and desorption kinetics are considered, the DB electrode presented superior performance, mainly due to its higher interparticle porosity that minimizes the distance of ion diffusion from the bulk solution to the inner surface, thus facilitating the access of the ions to the micropores. These results demonstrated that the faster kinetics provided by enhanced mass transfer in thin electrodes with high interparticle porosity can be decisive for the selection of the best electrode in CDI applications, specially aiming for future applications in flow-through CDI cells. Sequentially, different strategies were studied in order to optimize the desalination performance and the long-term operation stability of PAC/PTS electrodes. Additionally, the new sulfate-doped PAni-activated carbon (PAC/S) was proposed to investigate the influence of chemical and textural properties of the electrodes on the desalination stability. Chemical treatments with ethylenediamine and (3-aminopropyl)triethoxysilane were used to change the chemical surface groups and the potentials of zero charge (EPZC) to more negative values of the materials and promote asymmetry between the electrodes. Symmetric and membrane CDI (MCDI) configurations were also investigated for performance comparison. The control of the potential distribution in asymmetric cells was pointed out as an effective strategy to suppress the carbon oxidation reactions responsible for the SAC loss and improve the long-term stability. However, the best performance and long-term stability were achieved using PAC/PTS electrodes in the MCDI configuration. The use of ion-exchange membranes (IEM) had proved to be a feasible method to improve the electrosorption capacity by reducing the effect of co-ion expulsion and inhibit the faradaic reactions by limiting the transport of the electrochemically active species across the IEM. For this cell configuration, a remarkable value of SAC (~32 mg g-1 at 1.2 V), along with 100% of performance retention was observed over 100 cycles. Our findings enable a better understanding of how to mitigate faradaic reactions and improve the long-term stability of PAC electrodes, thus providing promising electrodes for large-scale CDI applications.
Deposição e caracterização de filmes finos do sistema Zn(1-x)CoxO obtidos por spray pirólise para aplicação em sensor de ozônio
(Universidade Federal de São Carlos, 2021-04-19)
Onofre Ramirez, Yina Julieth
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Silva, Luís Fernando da
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https://lattes.cnpq.br/7422167106177474
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Godoy, Marcio Peron Franco de
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https://lattes.cnpq.br/2609654784637427
The current concern about reducing the harmful effects of air pollution on environment and human health requires adequate gas sensors that allow an efficient control and monitoring on a wide range of pollutants. This encourages the research on new materials and on the modulation of features in order to allow the optimization of gas sensing properties of the current devices. Herein we investigate the effect of the cobalt concentration and the annealing, under controlled atmosphere, on the structural, microstructural, surface chemistry, optical, and gas sensing properties of Zn(1-x)CoxO thin films prepared by spray pyrolysis technique. The films were deposited on Si (100) substrates using a acetate route. The X-ray diffraction (XRD) results indicated that the films have the hexagonal wurtzite ZnO phase and that a loss of crystallinity occurs with Co addition. Scanning Electron Microscopy (SEM) micrographs revealed the films surface are porous and formed by grains, whose average size decreases with Co addition. X-ray photoelectron (XPS) and photoluminescence (PL) spectroscopies results of Co-doped thin films confirmed the presence of Co in the oxidation state +2. The XPS measurements also revealed a higher concentration of oxygen vacancy (Vo) for 2.5 mol% Co film and the effect of annealing in reducing the Vo concentration in films. The pure ZnO film exhibits two broad emission bands in the ultraviolet and green energy range, associated with excitonic transitions NBE and defects related to zinc vacancy (VZn)/ interstitial oxygen (Oi), respectively. Incorporation of Co in ZnO matrix leads to an attenuation of NBE band emission and favored defect-band emissions in the red and the blue energy range, which are respectively attributed to the Co2+ ion, and to the interstitial zinc (Zni)-related defect. The annealing of pure ZnO film promoted the formation of Oi-related defect in the red energy range, and VZn-related defect in infrared energy range when carried out on oxygen and nitrogen atmosphere, respectively. For Co-doped films, the annealing increased the concentration of Zni or Oi/VZn-related defects depending on Co concentration and atmosphere. The DC electrical resistance measurements performed to evaluate the ozone gas sensing of Zn(1-x)CoxO films showed an improvement of the ozone sensor response with the reduction of film thickness and with the Co-doping, where the x= 2.5 mol% is the optimal Co concentration. Moreover, cobalt-doped zinc oxide films (ZnCoO) showed selectivity toward ozone gas in a large concentration range (21-696ppb) and then emerging as a promising material for practical application in ozone gas sensing. The conclusions derived from the average grain size, the point defects and the effect of annealing on the gas sensing suggest that the overall improvement of the ozone sensor response could be attributed to the presence of Zni and Vo-related defects, that act as active sites on the films surface favoring the adsorption of oxygen species.
Proposta de um sistema de bicicletas compartilhadas para uma cidade de médio porte
(Universidade Federal de São Carlos, 2021-04-19)
Olmos, Camilo Andrés Mora
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Guerreiro, Thais de Cassia Martinelli
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https://lattes.cnpq.br/2650555786682535
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https://lattes.cnpq.br/0570100407106917
The bicycle-shared systems (BSS) in the world have provided many benefits to cities such as improvements in traffic, health, and the environment. The biggest success factor for shared bikes is the location of the stations. This work presents a proposal for a bicycle shared system for a medium-sized city (Araraquara, S.P.), establishing the locations of the stations and evaluating the characteristics of the municipality. Factors such as locations with a high concentration of travel (generating poles for trips), elements of the bus system, current and designed infrastructure for bicycles, points of interest in the city, topographic characteristics, and profile of bicycle users are considered. The proposed methodology uses the modeling of a Geographic Information System (GIS), which allows the determination of certain characteristics based on analyzes specific to geography such as distances, densities, mappings. In parallel, the GIS connects with decision-making models, such as the Analytical Hierarchical Process (AHP) and the Optimization of Multiple Objectives by Radio Analysis (MOORA). Such methods contributed to the construction of maps indicating the areas of high and medium possibility to locate the stations of the system of shared bicycles, from which three alternatives were generated that evaluated characteristics such as number of bicycles, type of system (manual or automatic) and operating cost. Of these alternatives, the most suitable proposes a mixed system, with a lower cost and an average of trips suitable for an appropriate operation. From the development of the work, it was also possible to characterize the participation of elements such as bicycle infrastructure, temperature and slope within the implementation of the shared bicycle system. Finally, with the progress of the work, Araraquara presented itself as a city with an important potential to implement a system of shared bicycles.
Rational design and engineering of a microbial cell factory for 3-hydroxypropionic acid production
(Universidade Federal de São Carlos, 2021-04-20)
Chaves, Gabriel Luz
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Silva, Adilson José da
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https://lattes.cnpq.br/3447469350644179
;
https://lattes.cnpq.br/7063262952154349
The US Department of Energy ranked the 3-hydroxypropionic acid (3-HP) among the Top 10 most promising value-added chemicals that can be derived from biomass in a biorefinery. This acid has great potential to serve as a building block for the industry, serving as raw material for paints, coatings, and polymers. Nevertheless, its production from chemical routes encompasses processes that are highly toxic and environmentally harmful. In this context, fermentative bioprocesses are a promising alternative for 3-HP production. Here, we proposed the obtention of an Escherichia coli strain genetically modified to produce 3-HP through the β-alanine pathway, yet poorly studied. To build an E. coli strain able to produce 3-HP, the genes that encode the last three reactions of the pathway were cloned and combined in the same plasmid (pEbtyGpD): pa0132 from Pseudomonas aeruginosa, ydfG from E. coli, and panD from Corynebacterium glutamicum. This first engineered strain, named PS100, produced up to 0.338 ± 0.044 g/L of 3-HP after 24 h of induction with IPTG using glucose as a carbon source. Surprisingly, cultivations on a mixture of glucose and xylose (1:1 on C-mol basis) yielded a final titer of 1.040 ± 0.050 g/L by this strain, from the same substrate amount. To optimize the production obtained from PS100, new genetic modifications were investigated through in silico optimization of a genome-scale metabolic model of E. coli K-12 MG1655. The model iML1515 was modified to include the heterologous reaction of β-alanine conversion to malonic semialdehyde, and three reactions were identified as potential metabolic targets for enhancing 3-HP production by E. coli cells: the reactions of alanine racemase (ALAR), L-alanine aminotransferase (ALAT), and L-valine transaminase (VALTA). These target reactions were modified in the strain PS100, generating the strain PSO107 that was able to improve nearly 2-fold the final titer of the acid when compared to PS100 in cultivations with glucose as carbon source, reaching 0.743 ± 0.016 g/L of 3-HP. For cultivations with the glucose:xylose mixture, a 10% increment was observed for the PSO107 strain compared to PS100, with the former reaching 1.147 ± 0.015 g/L of 3-HP. These results confirm that the targets predicted by the evolutionary optimizations of the genome-scale metabolic model were assertive and enabled an increment in the final production of 3-HP by the engineered E. coli strain.
Produção acadêmica sobre cultura organizacional em escolas de educação básica no Brasil de 2006-2020
(Universidade Federal de São Carlos, 2021-04-20)
Yamazato, Marcelo Oda
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Nascente, Renata Maria Moschen
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https://lattes.cnpq.br/3742955383665134
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https://lattes.cnpq.br/4135953867259858
This dissertation derives from an investigation which was developed within the Study and Research Group on School Organization: Democracy, Human Rights and Principals’ development - DEFORGES. Organizational culture in Brazilian schools was its theme, having as its problem the following question: how is the academic production on organizational culture configured in basic education schools in Brazil? Thus, the general objective was to understand the theoretical and methodological approaches to the subject in the articles, dissertations and thesis that constitute this production and the specific objectives were to map research on this theme from 2006 to 2020, systematizing its theoretical references, methodological procedures, and conclusions, and to analyze the theoretical matrices referring to culture in these studies. The methodological approach was the bibliographic one, carried out on SciELO and CAPES Theses and Dissertations Repository digital databases. Critical theoretical framework guided the results analysis, which indicated that: the most used research design was the case study; the most used data collection instrument was document analysis followed by semi-structured interviews; the most investigated level of education was elementary school followed by high school in public municipal and state institutions. The references of Edgar Schein, António Nóvoa and Heloísa Lück also stood out. In addition, it was possible to observe that the organizational culture was worked in relation to several topics, the most frequent being school management, change processes, democratic management, and school performance. In most of the works, the study of organizational culture was developed to analyze the school reality, relating to, and facilitating investigations on several other topics, being able to show the subjects' autonomy and their possibilities of construction and reconstruction of organizational culture. It was concluded that organizational culture is a concept that can contribute to research on schools, especially those that seek to investigate their dynamics, functioning and relationships. In addition, it became evident that organizational culture in the context of Brazilian education is still a yet to be explored theme that has the potential to subsidize school administration in its daily practices.
Resultados para o modelo de rumor de Maki-Thompson em árvores
(Universidade Federal de São Carlos, 2021-04-20)
Speroto, Adalto
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Vargas Júnior, Valdivino
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https://lattes.cnpq.br/1795859800919467
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Rodríguez, Pablo Martín
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https://lattes.cnpq.br/6412853511887386
In this work, we study the Maki-Thompson rumor model on infinite homogeneous trees which is formulated as a continuous-times Markov chain. This model can be defined as a system of interacting particles representing the spread of a rumor by individuals in a homogeneous tree. We assume that each individual can belong to one of three classes in a population represented by: ignorants, spreaders and stifles. A spreader tells the rumor to any of its ignorant (nearest) neighbors at a constant rate. On the other hand, also at the same rate, a spreader becomes a stifler after interact with other spreader (nearest neighbors) or a stifler. Still in this work, we extend our analysis to two generalizations, in the first one we assume that each propagator stops spreading the rumor right after being involved in a certain number of failed attempts and in the second we extend the Maki-Thompson model to Independent and identically distributed random trees. We study sufficient conditions under which the rumor either becomes extinct or survives with positive probability.
Distribuições combinadas
(Universidade Federal de São Carlos, 2021-04-21)
Caldas, Tainá Santana
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Diniz, Carlos Alberto Ribeiro
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https://lattes.cnpq.br/3277371897783194
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https://lattes.cnpq.br/9293603242121451
It is proposed a possible new line of research in which distributions are combined. Combined distributions are an alternative for adjusting continuous data that present different probabilistic behaviors. A combined distribution called Gucumatz is developed, composed of the symmetrical Normal and Cauchy distributions. Some properties of this distribution are studied, maximum likelihood estimation of augmented data is performed (EM Algorithm), regression model and simulation studies are developed. A set of real data is adjusted using the Gucumatz distribution.
A perspectiva dos gestores sobre a participação do usuário no projeto e a redução do tempo de processo
(Universidade Federal de São Carlos, 2021-04-22)
Ebisui, Victor Centurion
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Tonin, Luiz Antonio
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https://lattes.cnpq.br/1835542837415565
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https://lattes.cnpq.br/1835542837415565
Historically the market has become more dynamic and competitive, so customers needs and desires have become increasingly refined. Thus, clearly understanding the requirements and making the product available at the right time to the market become crucial competitive force for the business. As a result, the present study aimed to carry out an analysis seeking to identify an existing relationship between the use of customer interaction in the development phase of a new product, reducing the time of the project execution and, consequentialy, the time-to-market. This work was developed from a quantitative analysis in a consumer goods company from school supplies sector. For the evaluation of the central question, a questionnaire was made for people responsible to lead the new product development area of the company. It was possible to treat the information obtained and establish discussions and conclusions around the main idea. The results of the research demonstrate that the user's participation in the development stages of a new product can impact on the reduction of the time used in the project execution if its planned correctly and applied since the initial stages of product design.
Pólen como ingrediente funcional em pão: influência nas atitudes, percepção e expectativa gerada nos consumidores brasileiros.
(Universidade Federal de São Carlos, 2021-04-22)
Silva, Heloísa Pestana Mendes da
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Domingues, Maria Aliciane Fontenele
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https://lattes.cnpq.br/2932812185528590
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https://lattes.cnpq.br/4677729941461360
The search for a healthy lifestyle leads to a situation where several people start to take care of their health. From then on, they seek products of higher quality, preferably with health benefits, rich in vitamins, bioactive compounds, bioelements, and valuable nutrients. In this sense, bee pollen, which is rich in functional components, can satisfy these expectations when added to processed products and be better used as an ingredient in the food industry. One of the fastest-growing categories is the bakery category, mainly focused on producing artisanal or rustic bread, with the appeal of "more natural" or" healthier" because it does not contain synthetic additives in its composition. Thus, natural fermentation bread has been gaining market and winning more concerned about a healthier lifestyle. Given the above, we believe that it is important to study consumers' behavior concerning developing new products in the bakery sector. Thus, this study aimed to analyze the acceptance of artisanal hamburger bread added with bee pollen, as well as, how consumers perceive specific natural compounds for health promotion and their attitudes towards accepting this bread.
Desenvolvimento de eletrodo modificado com o solvente eutético profundo cloreto de colina/glicerol para a determinação simultânea de paracetamol e diclofenaco
(Universidade Federal de São Carlos, 2021-04-22)
Piton, Gabriela Rizzo
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Fatibello Filho, Orlando
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https://lattes.cnpq.br/9859737944357808
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https://lattes.cnpq.br/4015750386602441
In this master’s dissertation has investigated the use of deep eutectic solvents (DES) for the development of electrochemical sensors. DES was immobilized on the surface of a glassy carbon electrode (GCE) within carbon black (CB) nanoparticles in chitosan (CTS) films crosslinked with epichlorohydrin (ECH). During the electroanalytical method development for the simultaneous determination of acetaminophen (ACP) and diclofenac (DCF), the experimental conditions were optimized, such as composition and concentration of the DES within the modification, support electrolyte’s pH, time, and applied potential for the analytes pre-concentration, and instrumental parameters for the differential pulse adsorptive anodic stripping voltammetry technique (DPAdASV). The DES applied in this work were characterized by Fourier-transform infrared spectroscopy and conductivity measurements. The proposed modified electrode had its morphological structure characterized by scanning electronic microscopy, which allowed to observe morphological changes after incorporating DES into the CB film. The electrochemical characterization was given by electrochemical impedance spectroscopy to calculate electronic parameters, such as capacitance and charge transfer resistance, and by cyclic voltammetry to calculate the heterogeneous electron transfer constant (k0). The DPAdASV method resulted in linear responses in the range from 5.0 × 10−7 to 3.9 × 10−6 mol L−1 for ACP and from 5.0 × 10−7 to 1.5 × 10−5 mol L−1 for DCF, with limits of detection of 2.7 × 10−8 mol L−1 and 5.2 × 10−8 mol L−1 for ACP and DCF, respectively. The proposed method proved to be precise and selective, observed from studies of repeatability and effect of possible interferents besides addition and recovery studies. The accuracy of the proposed method was evaluated for the simultaneous determination of ACP e DCF in commercial pharmaceutical samples and biological fluids (synthetic urine and bovine serum). The obtained results were compared with those obtained by HPLC/UV-Vis.