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Auxílio ao diagnóstico automático do esôfago de Barrett utilizando aprendizado de máquina
(Universidade Federal de São Carlos, 2022-03-28) Souza Júnior, Luis Antonio de; Palm, Christoph; Papa, João Paulo; https://lattes.cnpq.br/9039182932747194; https://lattes.cnpq.br/0576836756526956
Esophageal adenocarcinoma is an illness that is usually hard to detect at the early stages in the presence of Barrett's esohagus. The development of automatic evaluation systems of such illness may be very useful, thus assisting the experts in the neoplastic region detection. With the strong growth of machine learning techniques aiming to improve the effectivess of medical diagnosis, the use of such approaches characterizes a strong scenario to be explored for the early diagnosis of esophageal adenocarcinoma. Barrett's esophagus as a predecessor of adenocarcinoma can be explained by some risk factors, such as obesity, smoking, and late medical diagnosis. This project proposes the development of new computer vision and machine learning techniques to assist the automatic diagnosis of the esophageal adenocarcinioma based on the evaluation of two kind of features: (i) handcrafted features, calculated by means of human knowledge using some image processing technique and; (ii) deeply-learnable features, calculated exclusively based on deep learning techniques. From the extensive application of global and local protocols for the models proposed in this work, the description of cancer-affected images and Barrett's esophagus-affected samples were generalized and deeply evaluated using, for example, classifiers such as Support Vector Machines, ResNet-50 and the combination of descriptions by handcrafted and deeply-learnable features. Also, the behavior of the automatic definition of key-points within the evaluated techniques was observed, something of a paramount importance nowadays to guarantee transparency and reliability in the decisions made by computational techniques. Thus, this project contributes to both the computational and medical fields, introducing new classifiers, approaches and interpretation of the class generalization process, in addition to proposing fast and precise manners to define cancer, delivering important and novel results concerning the accurate identification of cancer in samples affected by Barrett's esophagus, showing values around 95% of correct identification rates and arranged in a collection of scientific works developed by the author during the research period and submitted/published to date.
Desenvolvimento e otimização de método cromatográfico para separação de três ativos e suas respectivas impurezas com aplicação de planejamento fatorial
(Universidade Federal de São Carlos, 2022-03-28) Souza, Romero Moreira de; Pereira Filho, Edenir Rodrigues; https://lattes.cnpq.br/3394181280355442; https://lattes.cnpq.br/9229558047181689
An essential part of the development of a new drug is the development of methods to analyze the products during the stage of development and throughout their useful life to ensure quality and safety for patients. The analytical method must be indicative of stability, that is, capable of detecting, over time, changes in the physical, chemical or microbiological properties of a substance. Other important characteristics describe that they are specific methods able of accurately measuring the dosage of the active pharmaceutical ingredient (mg/tablet), degradation products (% of impurity) and other components of interest, without interference. In order to identify and quantify different components of a product's formulation, chromatographic techniques are widely used. By means of this technique it is possible to properly separate the substances present in the formulation and quantify several analytes in the same analytical run. Several factors interfere in the separation of components in the chromatographic method, highlighting the pH of the mobile phase, the type of material in the stationary phase, the type of solvent and its concentration in the mobile phase, among others. The goal was to use chemometric tools to explore the principles of separation of three drugs and their respective impurities and to develop an indicative method of stability by HPLC-DAD. The initial tests were performed on a sample built with the presence of the three actives and their impurities, which were added or generated through sample stress. Chromatographic separation was evaluated in screening and optimization tests. Screening was performed with a wide range of mobile phase pH and different chromatographic columns. Different organic solvents and rates of increase in organic solvent concentration (gradient time) along the analytical run were also evaluated. Data were processed using Fusion and Octave software. The analytical method indicative of stability for the separation of the three actives was efficiently developed and validated, presenting itself as selective, linear, accurate and precise. The use of chemometric tools proved to be efficient to detect the limitations of the method and to define the variables to obtain the best performance (greater separation and shorter analysis time).
Efeito do treinamento resistido sobre o coeficiente de controle de fluxo mitocondrial do cortex pré-frontal de ratas ovariectomizadas
(Universidade Federal de São Carlos, 2022-03-28) Cavalini, Diego Felipe; Shiguemoto, Gilberto Eiji; https://lattes.cnpq.br/9885031162656978; https://lattes.cnpq.br/9438602932981499
Introduction: During the aging of a woman, a process called menopause takes place, marked by hormonal changes (fall in estrogen, increase in follicle stimulating and luteinizing hormone). As a result of this phase, there are episodes of changes in brain functions (cognitive deficit, mood change and sleep disorders) that are sensitive to this hormonal variation, mainly related to the drop in estrogen, which in turn directly compromises the activity of an organelle, the mitochondria. It is suggested that resistance training improves mitochondrial functions, bringing non-pharmacological benefits to women who are in this phase. Mitochondrial function can be measured through cellular respiration, but the FCC method can also be used, which calculates the individual functioning of each protein that is coupled to the electron transport chain (ANT-1, ATP synthase and the phosphate exchanger) . Objectives: to evaluate the effects of ovariectomy and Resistance Training (RT) on the efficiency of the flow control coefficient (FCC) and oxygen consumption during coupled breathing of the Prefrontal Cortex of young mature rats, to evaluate the effects of ovariectomy and resistance training on the global and intrinsic functioning of the mitochondrial electron transport chain complexes of prefrontal cortex neurons, the activity of ANT-1, ATP-Synthase and Phosphate Exchanger in an "in vivo" model (biopsy ) of neurons in the prefrontal cortex. Methodology: 40 adult Wistar rats (rattus albinus norvergicus) were divided into 4 experimental subgroups: 1) Intact Sedentary (INT-SED), Intact Resistance Training (INT-TR), Sedentary Ovariectomized (OVX-SED) and Ovariectomized Resistance Training (OVX-TR), for the TR group, the training frequency happened 3 times a week for 12 weeks and the intensity was applied at 65%, 70%, 75%, 80% and 85% of the maximum load carried. Oxygen consumption of permeabilized brain tissue was performed in a high resolution oxygraph with MiR05, 37ºC, in the presence of glutamate (10 mM) and malate (5 mM). ADP (400 μM), oligomycin (1 μg/mL) and FCCP (carbonyl cyanide-4) (trifluoromethoxy) phenylhydrazone 0.2 μM] were added during the experiment. The titrations to establish the Flow Control Coefficient (FCC) were carried out in the ANT, in the Phosphate Exchanger and in the ATP-Synthase. Results: Ovariectomy increased the body mass of the rats, tibia size there was no significant difference, thus showing that all rats had similar growth. Ovariectomy negatively affected the FCC of ANT-1, ATP synthase in the OVX-SED group, and the phosphate carrier. The negative effects of ovariectomy were reversed by RT. Discussion: ovariectomy promoted a decrease in the functioning capacity of the electron transport chain in the prefrontal cortex, evaluated by the FCC dysfunction found in all analysis proteins, ANT-1, ATP-Synthase and Phosphate Exchanger, a fact in A highlight was the use of RT as an important therapeutic tool to reverse the deleterious effects caused by ovariectomy on the FCC of the mitochondrial respiratory chain of trained rats. Conclusion: The deleterious effects of ovariectomy negatively impact the functioning of the mitochondrial respiratory chain in the prefrontal cortex, a fact related to the negative changes in the proteins evaluated in this study by the flow control coefficient. The applied resistance training proved to be effective in preventing the deleterious changes promoted by ovariectomy, since the evaluated proteins maintained their activities at satisfactory levels.
Ordinary and twisted K-theory
(Universidade Federal de São Carlos, 2022-03-28) Clemente, Gabriel Longatto; Ruffino, Fabio Ferrari; https://lattes.cnpq.br/2512107188781159; https://lattes.cnpq.br/9621252774701915
The main topic of this thesis consists in Ordinary and Twisted Topological K-Theory. We begin by describing generalized cohomology theories through the Eilenberg-Steenrod Axioms, in order to set Ordinary K-Theory in these terms. This allows us to deduce its structural properties from the framework of generalized cohomology. Then, we expose the elementary notions of Spin Geometry to relate it to Ordinary K-Theory through the Atiyah-Bott-Shapiro Theorem. This result enables us to construct the Thom isomorphism as well as the integration map, which is known as Gysin map. After that, we rephrase Ordinary K-Theory by means of the Index map, which provides an interpretation of K-Theory through homotopy classes of continuous functions. Afterwards, we deal with Twisted K-Theory. First, we introduce the Grothendieck group of twisted vector bundles as a model for finite-order Twisted K-Theory. Then, we describe the infinite-dimensional model, through suitable bundles of Fredholm operators, that holds for twisting classes of any order. Finally, we compare these two models in the finite-order setting.
Urbanidade e vitalidade nos espaços públicos em novas áreas residenciais verticalizadas: estudo de casos em Londrina - PR e Ribeirão Preto - SP
(Universidade Federal de São Carlos, 2022-03-28) Esteves, Juliana Cardoso; Castro, Carolina Maria Pozzi de; https://lattes.cnpq.br/2178910002833930; https://lattes.cnpq.br/8180214459480752
The projects of residential condominiums aimed at the middle and upper classes tend to privilege the interior of the building and the design of its facades, but few consider its relationship and integration with the public space and the people who use it, who have also not received due attention. of urban managers, since the adaptation of the city to the car absorbed a large part of the investments. This work aimed to analyze how the configuration of the built environment, through its morphological elements, architectural typologies, and socio-spatial practices, interferes with the vitality and urbanity of cities, especially public spaces in vertical areas. The research method adopted was the study of multiple cases in recently verticalized areas in medium-sized cities and took place in three phases: development of research instruments (observation sheets, questionnaires, interviews, thematic maps) and analysis criteria, based on the studied literature; data collection in the cities of Londrina – PR and Ribeirão Preto – SP and systematization and analysis of the data collected. To verify the main attributes of vitality and urbanity in the spaces studied, two dimensions of analysis were adopted: physical, in which questions of urban form were evaluated, and social, in which the relationship between the user and the urban space was verified. From the literature point of view, the thesis contributes to the articulation of the concepts of urbanity and urban vitality. The analysis of data and research results showed that urban form plays an essential role in the development of vitality and urbanity in public spaces in cities, as they directly interfere in the use of spaces and in the perception of users. However, this is directly linked to the experiences, specific needs, and cultural identities of each one. The case studies demonstrated the central hypothesis of the research: the same vertical typology, arranged in the urban site with different spatial arrangements, generate different urban qualities, with repercussions on aesthetic, spatial, mobility and safety perception, creating public spaces with different vitality and urbanity.
Estudos sobre a acessibilidade aos sítios de zeólitas para aplicação em catálise básica
(Universidade Federal de São Carlos, 2022-03-28) Silva, Juliana Floriano da; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/4674602775309738
The application of zeolites in catalysis is restricted when bulkier molecules are involved, for example, in the manufacture of fine chemicals, where the reactant molecules are unable to access their micropores. A solution to this problem could be the synthesis of zeolites containing mesopores to improve accessibility to sites. Zeolites have intrinsic basicity, due to residual negative charges in their framework, which are generated by the presence of trivalent aluminum atoms with tetrahedral coordination. The functionalization of the surface of zeolites with amine groups, through the anchoring of silanes containing basic nitrogenous species, is one strategy to improve their basicity. In this context, this work studied the synthesis of 4A zeolites through the constructive method (bottom-up) using the organosilane surfactant [3 (trimethoxysilyl) propyl] octadecyldimethyl ammonium chloride (TPOAC) as mesopores generator at different concentrations in the synthesis mixture (TPOAC/Al2O3= 0-0.09). These zeolites were evaluated in the Knoevenagel condensation between benzaldehyde and ethyl cyanoacetate, which is influenced by the accessibility to the catalytic sites, due to the volume of the molecules involved. This study also evaluated the improvement of the basicity of zeolites through the functionalization of their surface with amine groups, for this, the zeolite containing the highest amount of mesopores, and the conventional zeolite were treated with aminopropil-trimetoxisilano (APTMS). 4A zeolites with mesopores were formed in the presence of TPOAC at the different concentrations evaluated, showing an increase in the external surface. The benzaldehyde conversions were higher when using zeolites with mesopores instead of conventional 4A, due to the improved accessibility of the to the catalytic sites. In addition, the reaction catalyzed by zeolite with mesopores has a lower activation energy than that catalyzed by conventional 4A zeolite. It was not possible to anchor APTMS on the surface of the conventional zeolite, probably due to the low external surface and consequent lack of available silanol groups that can react with the silane. On the other hand, the functionalization of zeolite with mesopores was possible, due to its high surface that provides a higher amount of silanol groups compared to the external surface of the conventional zeolite crystal. Consequently, zeolite with mesopores treated with APTMS has superior catalytic activity in Knoevenagel condensation, due to improved accessibility and addition of catalytic sites.
Desenvolvimento de um secador de bandejas para a secagem de folhas medicinais e análise da secagem de ramos de barbatimão (Stryphnodendron adstringens)
(Universidade Federal de São Carlos, 2022-03-28) Gardenal, Amanda Coloca; Ferreira, Maria do Carmo; https://lattes.cnpq.br/7070885875161111; https://lattes.cnpq.br/0534137332015210
Barbatimão bark (Sryphnodendron adstringens) has been used in folk medicine for years to treat many diseases. Recently, studies indicated the potential of barbatimão leaf extract as a chemopreventive agent and as a promising candidate for the development of an antineoplastic drug for breast cancer. However, after harvesting, the leaves begin an irreversible degradation process and it is necessary to dry them to retain their properties until processing. The objective of the present study was to develop a multistage tray dryer, which operates as sequential batches, to promote material mixing and improve the use of thermal energy for drying medicinal leaves. Firstly, barbatimão branches were dried in a thick layer using 400 g of raw material, resulting in a heterogeneous product in terms of moisture. In general, the drying kinetics curves for different temperatures in oven and fixed bed operations were distinguishable; for the tray dryer, the drying curves were obtained for each stage individually, simulating the real operation by using partially dried material below each tray. It was decided to operate the dryer with 4 stages using the minimum distance between them (11.88 cm) and drying air at 60ºC and 0.4 m/s. The individual curves obtained for the 4 stages were very similar, except for the required time to reach the equilibrium moisture, which was considerably higher for superior stages. Page's model was better suited to the experimental data and, by using it, it was possible to estimate a residence time of 9.5 minutes for each stage, totaling 38 minutes for drying 100 g of barbatimão branches and obtaining a product with 10% of moisture (w.b.). The experimental data were consistent with the theoretical drying curve and the product obtained had moisture content lower than 10% (w.b.). The moisture of the final product was homogeneous, even though the mixture of material in the tray during the operation was partial, since, despite the division of the tray into three sections, the branches were concentrated in the central region, creating empty spaces. This issue was mitigated by manually vibrating all tray sections after the material was dumped. Thus, the developed dryer met the proposed objectives. The cumulative drying efficiencies of the one- and four-stages operations, drying 100 g of material, were 3.16 and 3.98% respectively, representing an increase of 25.6% for the tray dryer. The values obtained for L*, a*, b* and a*/b* for the dry products in different configurations and temperatures didn’t present statistically significant differences compared to the values of these parameters for raw leaves. The maintenance of the initial leaf color is a possible indication that the bioactives have been well preserved.
Size spectra in tropical streams: effects of land use changes
(Universidade Federal de São Carlos, 2022-03-28) Resende, Giovanna Collyer; Perkins, Daniel; Saito, Victor Satoru; https://lattes.cnpq.br/3312862423985585; https://lattes.cnpq.br/4214652920982318
Changes in land use have altered the structure and functioning of ecosystems, including trophic interactions that control the flow of matter and energy. We investigated the differences between the relationship of log10-biomass and log10-body size classes (size spectrum) of impacted and preserved streams along a land use gradient, going from almost complete coverage by native forest to complete agriculture of monocultures. The size spectrum characterizes how many organisms of each size class are maintained in the communities and is therefore a way of accessing the energy flow between trophic levels. We used data from macroinvertebrates of 30 streams, located in southeastern Brazil. We predicted that impacted streams could have more or less basal resources available (i.e. higher or lower size spectra intercept, respectively), and in both cases we expected a higher energetic cost, sustaining less biomass in large size classes (i.e. steeper size spectra slope). We also expected more deviations in the model in impacted streams (lower regression R²), due to the high energy demand and low energy efficiency transfer, causing organisms to feed outside their ideal predator–prey mass ratio. Our results demonstrated that impacted streams have fewer small organisms available at lower trophic levels (lower intercepts) than preserved streams, but with a more efficient energy transfer (shallower slopes). This may be due to few strong interaction links related to communities with less diversity and the simplification of the food web in impacted environments, which tends to decrease stability and enhance vulnerability to stochastic events. Preserved streams are more complex and have more energy pathways possible, resulting in weaker interaction strengths, which leads to a higher community stability. We also demonstrated that deviations in the model do not vary systematically across the land use gradient, as well as its structure is not defined by the land use type. Our study represents a step forward to understand how anthropogenic impacts affect trophic interactions and ecosystem functioning in tropical streams.
Reflexões acerca da acessibilidade na educação dos surdos durante o ensino remoto a partir de debates acadêmicos em lives
(Universidade Federal de São Carlos, 2022-03-28) Freitas, Larissa Maria de Carvalho; Lacerda, Cristina Broglia Feitosa de; https://lattes.cnpq.br/9468232016416725; https://lattes.cnpq.br/7616266805096585
This work has as its theme the reflections about accessibility in the education of the deaf during Remote Teaching from academic debates in lives. Thus, this research considered to answer the following question: How is accessibility for the deaf happening during Remote Teaching?. With the general objective: To research what was being said about the accessibility of deaf students during remote teaching in the Covid-19 pandemic from academic debates in lives. And as specific objectives: Recognize new perspectives on accessibility in the education of the deaf during remote teaching during the Covid -19 pandemic; Understanding the challenges of remote teaching for the deaf student, based on academic/scientific reflections present in public debates in the Lives published from March 2020 to August 2021. This is a documentary research with a qualitative approach. For this, the Lives produced and promoted by scientific societies were chosen as primary documentary sources in an order of priority for publications by Universities, Institutes, Support Centers and scientific societies, on the theme "Education of deaf students in remote teaching". The analysis of the Lives was carried out considering two analytical axes: 1) Accessibility conditions for the deaf in remote teaching, and 2) Consequences of this accessibility for deaf students in remote teaching. In view of this, the results of axis 1) showed that the accessibility conditions in the education of the deaf in remote teaching was challenging due to the barriers faced, ranging from the lack of digital equipment, to obstacles in the platforms and tools of communication by video call to remote classes. The results of axis 2) showed that the consequences of these conditions were: academic losses; lag in remote learning; impossibility of understanding between teacher-interpreter-student; and segregation of the deaf student. It was concluded that accessibility for the deaf student was among many challenges, and in the face of this, teachers in the lives discussed several possibilities and methodological strategies for the education of the deaf during remote classes, which allowed reflections and exchanges between teachers in the debates. academics in the lives.