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Catalisadores de Au/ZrO2 e Au/In2O3/ZrO2: Efeito das propriedades eletrônicas e estruturais na atividade para desidrogenação do etanol e hidrogenação de CO2
(Universidade Federal de São Carlos, 2022-10-28) Augusto, Thiago de Melo; Bueno, José Maria Corrêa; https://lattes.cnpq.br/0157452280626031; https://lattes.cnpq.br/5261437566516289
Au/ZrO2 and Au/In2O3/ZrO2 catalysts were developed for CO2 hydrogenation reaction and Au/ZrO2 for ethanol dehydrogenation. The monometallic gold catalysts supported on ZrO2 with different contents (0.3 to 5.0%w/w) were prepared by deposition-precipitation (DP) and analyzed by HRSTEM, DRIFTS-CO and in situ XPS as well as other characterization techniques. HRSTEM analysis proved the high dispersion of Au nanoparticles (NPs) with an average size around 15 Å. The ulltraestructural analysis also verified the presence of particles smaller than 20 Å (metal clusters) and isolated atoms with 2D and 3D configurations. The activity verified by ethanol dehydrogenation tests was higher for catalysts with Au content <1%. In situ XPS analyses indicated that a high dispersion of Au NPs, associated with heat treatment conditions at low temperature (200°C), promoted an increase in BE Au 4f7/2 binding energy, accompanied by surface defects and characterized by CO adsorption.The DFT results using clusters (3 and 13 Au atoms), indicated that the activation of ethanol on the surface of the clusters is not favorable, it must occur at the Au/ZrO2 interface and the determining step occurs on the surface of the clusters. The presence of low coordination sites formed by surface defects through the decrease of the Au charge and low heat treatment temperature suggest that they are of the 2D surface type, providing high catalytic activity and low activation energy (Ea) for the reaction. The increase of temperature in He treatment of the samples (from 200 to 600°C) increases the coordination number (NAu-Au) and the bond distance (RAu-Au), promoting a decrease of the catalytic activity. The adsorption of CO in linear form to the bridge type is favored with increasing Au loading and heat treatment temperature in He. This behavior is accompanied by the increase of NAu-Au and RAu-Au. Removal of defects on the surface by thermal activation leads to a decrease in electronic density and catalytic activity. Au/ZrO2, In2O3, In2O3/ZrO2, Au/In2O3, and Au/In2O3/ZrO2 catalysts were also evaluated for the CO2 hydrogenation reaction at high pressure (50bar). HRSTEM indicated a high dispersion of the Au on the support (In2O3/ZrO2) and of the In2O3 nanoparticles on the ZrO2. XPS spectra confirmed the interaction between In and Zr by deviations in the binding energy for the 3d 5/2 level of In and Zr and by differences between the reduction profiles by TPR-H2 for the bulk (In2O3) and the In2O3/ZrO2.Ex situ and in situ Raman, and XPS allowed confirming the increase in vacancies for this system with variation in the relative intensities of the decayed spectra. The yield to the methanol product was significantly higher for the Au/In2O3/ZrO2 system compared to the others (Au/ZrO2, In2O3, In2O3/ZrO2, and Au/In2O3), indicating that clusters and/or NPs of Au, as well as highly dispersed In2O3 NPs on ZrO2 favor the formation of oxygen vacancies in the active sites, increasing the CO2 adsorption strength, stabilization of reaction intermediates, and decreasing the reverse reaction of CO production with ~70% selectivity to methanol.
A relação forma e conteúdo dos nexos conceituais de contagem em aulas online para crianças de 1º ano do ensino fundamental
(Universidade Federal de São Carlos, 2022-10-28) Pereira, Patrícia; Sousa, Maria do Carmo de; https://lattes.cnpq.br/6637658562543505; https://lattes.cnpq.br/5172215720465911
This present research of a typically historical bibliographic-documentary qualitative nature had as theoretical and methodological foundation the historical-dialectical materialist paradigm and was conducted by the following question: "What relationship between form and content is explained in online classes for children of the 1st year of elementary school who present the conceptual concepts of counting? The objective of this study is to analyze the relationship between the form and content of the conceptual index letters (numerical sense, one-on-one correspondence, sequence/ordering, grouping) presented in online classes for children in the 1st year of elementary school. The thesis defended was that the relationship between form and content of the conceptual links of the count directly implies the relationship between teaching and learning. For the construction of the information we attended and analyzed 37 online mathematics classes transmitted by CMSPi (35.92%) of out a total of 103, during the pandemic, for children enrolled in the initial grades, elementary school in the State network of São Paulo, in the period from 27/04/2020 to 29/10/2020, in order to understand how and what conceptual connection of counting are presented, identifying the relationship form and content of these issues. The results presented showed that counting cones were addressed in online classes: one-on-one correspondence, grouping/ordering and sequence, through challenges and use of manipulated concrete material such as tampons and toothpicks. Considering the definition of numerical sense this point was not addressed in any of the online classes analyzed. In relation to the contents addressed in the classes, there is the prevalence of numerical representation in the decimal base, which is immediately indicated, after the children make use of the correspondence one by one when they are faced with the control of quantitative movements. This form of control is called counting by teachers who organize and present online classes. In this sense, we found that online classes prioritized the form through the use of manipulateable concrete materials, such as tampons, chips and toothpicks, with emphasis on the perceptible elements of the concept that manifest themselves in the colors of objects and numerical representations. The concept of counting is restricted to the indication by children of the objects from the correspondence one by one with the little fingers and immediately, they must represent the quantities by the numerical symbols that are presented in the numerical basis ten. Number is synonymous with numeral. Content is synonymous with form. The idea of quantity becomes synonymous with the numeral that represents quantity. The zero digit is not treated. Children are not known that the zero digit is a placekeeper and that numerical base 10 is positional because it consists of regular groupings.
Sobreposição de transformações e desafios: experiências de mães de adolescentes na pandemia da COVID-19
(Universidade Federal de São Carlos, 2022-10-28) Alem Filho, Fabio; Wernet, Monika; https://lattes.cnpq.br/6056127658896265; https://lattes.cnpq.br/7378179768814680
In the tangle of social relations, adolescence is processed and adolescents emerge. Adolescence is part of the individual and family life cycle, encompasses particular development processes towards identity assumptions and life projects, during which transformations are experienced at different levels. The COVID-19 pandemic imposed changes in social dynamics, among which is the tendency for adolescents to stay at home. This study proposed to explore the perception of parents about adolescence in the context of the pandemic. The proposed objective was to elucidate meanings and behaviors of parents in supporting adolescents in the COVID-19 pandemic. This is a qualitative study with a descriptive and exploratory approach, supported by Symbolic Interactionism and thematic Content Analysis. Semi-structured interviews were developed with mothers of adolescents between the 1st half of 2021 and the 2nd half of 2022, enabling and encouraging a space for speech to share perceptions and afflictions regarding the growth of children in a scenario of uncertainty. From the interviews, three categories were created: interaction with the adolescent in transformation; relations in the face of the pandemic and its consequences; adaptations, revelations and concerns arising from living together. This study provided a space for family discussion that enabled reflections on topics not always addressed in family life and that can have positive consequences for raising and living with adolescents. we believe that this research can contribute to deepening the available knowledge about families, adolescents and the pandemic, in order to support health professionals in the care and monitoring of families and adolescents, as it brings important discussions about family life during the process of social isolation and favors the construction of knowledge to support these individuals who, many times, are not assisted with quality due to lack of understanding and knowledge on the part of professionals.
Produção de ácido hialurônico microbiano: viabilidade econômica e avaliação de impactos ambientais
(Universidade Federal de São Carlos, 2022-10-28) Harth, Matheus Lopes; Furlan, Felipe Fernando; https://lattes.cnpq.br/4136352953168873; https://orcid.org/0000-0002-0438-5257; Horta, Antonio Carlos Luperni; https://lattes.cnpq.br/5923938048634505; https://orcid.org/0000-0002-3042-0351; https://lattes.cnpq.br/4285466839275946; https://orcid.org/0000-0003-3549-6379
Hyaluronic acid is a biopolymer with unique structural and rheological properties, that, initially, was produced by extraction from animal tissue, from rooster comb. However, it used non-ecofriendly solvents (chloroform) and high purification costs to remove contaminants from the rooster comb motivated its manufacture from Streptococcus zooepidemicus bacteria cultivation. Considering this, our study proposed to do a techno-economic-environmental analysis of microbial hyaluronic acid production incorporated to a bioethanol biorefinery with S. zooepidemicus. The techno-economic analysis was conducted in EMSO, while the environmental analysis was done via Life Cycle Analysis, with the approach of gate-to-gate. At first, sugarcane juice was evaluated as carbon source and the required steam and electricity were provided from the sugarcane factory, which resulted in a net present value (NPV) of US$ 18.43 million with a return-on-investment rate of 12.5%. Economic feasibility can enhance further by utilizing more fractions from the biorefinery, such as yeast surplus for yeast extract production and not adding the salts to the cultivation medium, which increase NPV in 37.1% and 11.6%, respectively. From the environmental point-of-view, the Life Cycle Analysis showed the step with more environmental impact was the Production, especially the sodium hydroxide consumption for the cleaning-in-place and pH control, representing 78% of the total impact for Global Warming Potential. As the cleaning-in-place cannot be suppressed due to rules of regulatory agencies, we assessed the effect of not controlling the cultivation pH and assess its impact by reducing sucrose conversion to 50%. Such change made the process economically unfeasible, confirming what the shaken flasks cultivation showed: pH control has a significant effect on the cultivation of S. zooepidemicus, especially in the growth aspect of it.
Avaliação remota da tolerância ao exercício e das variáveis fisiológicas no Teste de Degrau de seis minutos e nas Atividades de Vida Diária por meio de Tecnologia Vestível em pacientes após hospitalização pela COVID-19
(Universidade Federal de São Carlos, 2022-10-28) Viana, Daiane Roberta; Di Lorenzo, Valéria Amorim Pires; https://lattes.cnpq.br/9071791546812165; https://lattes.cnpq.br/2978491508629378
Introduction: Patients with COVID-19 may have different impairments, especially in the most severe cases requiring hospitalization and intensive care. These impairments may be present even after hospital discharge, therefore, assessing exercise intolerance, the behavior of regulators and the level of physical activity of patients become fundamental. Among the forms of evaluation are the Six-Minute Step Test (6MST), Activities of Daily Living (ADL) and the use of wearable technology. Therefore, this dissertation resulted in two studies: Study 1 – Objectives: Verify and identify predictors of exercise intolerance assessed by the remote 6MST and compare performance, peripheral oxygen saturation (SpO2), and the feeling of dyspnea and fatigue in the test among patients who were hospitalized for up to 10 days with those who stayed more than 10 days due to COVID-19. Methods: This was a cross-sectional observational study, carried out by telemonitoring, of patients on average 30 days after hospital discharge due to COVID-19. The patients were evaluated by video call in two moments, the first moment was an initial evaluation for data recording and application of the inclusion criteria, and in the second moment the 6MST was performed. For monitoring during the test, patients received a 20-centimeter-high step in their homes, an automatic blood pressure device, a pulse oximeter and a modified Borg scale (0-10). Patients were divided into two groups: those who were hospitalized for up to 10 days (G≤10) and those who were hospitalized for more than 10 days (G>10). Results: Eighty patients were evaluated and it was verified that the length of hospitalization, cardiovascular and respiratory diseases, age and gender had a significant effect (adjusted R2=0.40) on the mean number of steps in the 6MST. In addition, 44 were hospitalized for up to 10 days (G≤10) and 36 for more than 10 days (G>10), and it was possible to verify that there was a significant difference between the groups regarding the need for intensive care (p<0.01), 6MST performance (p=0.04) and in the presence of oxygen desaturation (p<0.02). Conclusion: With the present study, it was possible to verify that the length of hospitalization, cardiovascular and respiratory diseases, age and gender had an influence on the exercise intolerance of patients after hospitalization for COVID-19 and that patients who were hospitalized for more than 10 days, showed greater exercise intolerance and desaturated more than patients who were hospitalized for up to 10 days, even 30 days after hospital discharge. Study 2 – Objectives: To characterize the responses of physiological variables during the simulation of an ADL circuit in relation to the physiological responses presented in the remote 6MST of patients after hospitalization for COVID-19 through wearable technology. In addition to verifying the association of physiological responses during ADL, exercise tolerance is verified by 6MST and physical activity level. Methods: This was a cross-sectional observational study carried out by telemonitoring patients after hospital discharge due to COVID-19. The patients underwent an initial assessment via video call and those eligible for the study received the material to perform the 6MST and the ADL circuit at their homes, including the smart T-shirt, made up of sensors that estimate the Frequency variables Respiratory (BR); Tidal volume (VT); Minute Ventilation (VE); Heart Rate (HR) and Cadence (CAD). For the evaluations, the patients were instructed to use the smart shirt for eight consecutive days for at least eight hours a day, and on the seventh day the 6MST was performed and on the eighth day an ADL circuit, both by video call. Results: Thirty-seven patients were evaluated and it was possible to verify significant differences between the ventilatory and cardiac variables during the execution of the 6MST with the ADL circuit and a moderate positive correlation between performance in the 6MST by the number of steps with CAD during the monitoring of the free ADL (R=0.594, p=0.000), correlation between performance in 6MST with the ventilatory variables in 6MST and in ADL1, however, there was no correlation between CAD in the monitoring of free ADL with the ventilatory and cardiac variables. There was also a moderate negative correlation between CAD and length of hospital stay (R= -0.590, p=0.000), and a weak negative correlation between CAD and the need for intensive care (R= -0.379, p=0.027) and 6MST performance with length of stay hospitalization (R= -0.374, p=0.023). Conclusion: The responses of the VE and HR variables during the ADL reached lower values when compared to the values reached in the 6MST. Both ventilatory and cardiac variables in 6MST were able to moderately predict the responses of the same variables in ADL, as well as the performance in 6MST was able to predict the level of physical activity, with longer hospitalization time and the need for intensive care negatively influencing the patients' exercise tolerance after 30 days of hospital discharge due to COVID-19.
Sensibilidade de abelhas brasileiras a agrotóxicos: avaliação de risco ambiental baseada no modelo Apis mellifera Linnaeus, 1758 (Hymenoptera, Apidae)
(Universidade Federal de São Carlos, 2022-10-28) Lourencetti, Ana Paula Salomé; Nocelli, Roberta Cornélio Ferreira; https://lattes.cnpq.br/8934724759636382; https://lattes.cnpq.br/6697139742938622
Ecotoxicological tests realized to assess the environmental risks of pesticides to bees used by countries around the world are based on the protocols developed by the Organization for Economic and Cooperation, where is recommended the use of isolated active ingredients in surrogate species Apis mellifera Linnaeus, 1758 (Hymenoptera, Apidae). Once the representativeness of these protocols concerning the surrogate and pesticide mixtures is pointed out as gaps regarding the pesticide risk assessment, the development of ecotoxicological studies about stingless bees is a crucial step toward achieving a more protective regulatory process in Brazil. The present work evaluated the toxicity of a neonicotinoid commercial product, isolated and combined with an herbicide and a fungicide in three species of stingless bees considered possible surrogates for the assessment of environmental risk in pollinators in Brazil Tetragonisca angustula Latreille, 1811 (Hymenoptera, Apidae), Scaptotrigona postica Latreille, 1807 (Hymenoptera, Apidae) and Melipona scutellaris Laitrelle, 1811 (Hymenoptera, Apidae).Through adapted oral toxicity tests and comparison of the sensitivity of these bees with the current biological model, we highlight that existing protocols do not protect stingless bee biodiversity due to the greater sensitivity found in representatives and due to toxicological interactions when the insecticide was offered in binary combinations. Therefore, it is a major necessity to incorporate these pollinators into the Brazilian environmental risk assessment process and create regulations regarding the use of mixtures before or after pesticide application.
Caracterização da diversidade e estrutura genética de uma população invasora e investigação de possíveis híbridos entre as espécies ameaçadas Leontopithecus rosalia e Leontopithecus chrysomelas
(Universidade Federal de São Carlos, 2022-10-28) Aliaga Samanez, Gabriela Guadalupe; Freitas, Patrícia Domingues de; https://lattes.cnpq.br/5647631868534064; https://lattes.cnpq.br/9717595663455527
The introduction of non-native species is an event that can jeopardize the conservation of native species. The introduction of alien species is usually based on a few individuals and is linked to impacts related to the founder effect and the loss of genetic diversity, which is dependent on the initial effective population size, the population growth rate, and the characteristics of the new colonized environment, which may or may not provide adaptation to it. Invasive species can also favor hybridization with native species, when both species meet and manage to mate, which can be detrimental to biodiversity when one or both pure progenitor strains or species become extinct. The creation of contact zones between species that do not naturally co-occur can therefore pose a pressing threat to biological conservation. This is the case of a specific region of Serra da Tiririca State Park, located in the municipality of Niterói, Rio de Janeiro (RJ), where two pairs of the threatened species Leontopithecus chrysomelas (the golden headed lion tamarin, GHLT, endemic to the Atlantic Forest of Bahia) and a pair of Leontopithecus rosalia (the golden lion tamarin, GLT, endemic to the Atlantic Forest of Rio de Janeiro) were released in the 1990s. Due to the favourable conditions present in this area, these animals were able to adapt and reproduce successfully, generating a new population outside the natural range of L. chrysomelas. Over two decades, this population increased its density exponentially, and it was estimated that there were about 200 individuals, with phenotype of L. chrysomelas in that area in 2009, no individuals with the phenotype of L. rosalia were observed. In view of this event, and the fact that at that time there was only the suspicion of a possible illegal introduction of L. chrysomelas into the Niteroi region, an alternative measure to contain the growth and advance of this population to adjacent areas of natural occurrence of L. rosalia, was to carry out the translocation of individuals with phenotype similar of L. chrysomelas to a fragment of Atlantic Forest, located on the RPPN (Private Natural Heritage Reserve) Veracel Celulose in Belmonte, Bahia. In 2015, however, the illegal introduction of L. chrysomelas and also L. rosalia was confirmed. Although these individuals had the phenotype of L. chrysomelas, it is known that hybrids, besides having phenotypes intermediate to the inter-crossing species, can be more similar to only one of the parental species. Considering that both L. rosalia and L. chrysomelas are species classified by the IUCN as "endangered", investigating the existence of hybrids in this population and characterizing their genetic diversity and structure is relevant for appropriate management measures in regions where currently there are descendants of this population. In this context, the main objective of this study was to carry out genomic and genetic analyses to investigate the occurrence of hybridization and to characterize the genetic diversity and structure of this population. The data showed no signs of hybridization in the Niteroi population, confirming that the individuals are from the species L. chrysomelas. Additionally, genetic diversity values were comparable to those observed for other Leontopithecus populations, showing the absence of negative founder effect consequences and the excellent capacity of the species to re-establish its diversity in the Niteroi region. These findings are relevant to adequately manage individuals from the invasive population and for the conservation programs of both pure species.
Célestin Freinet: história, política, princípios, técnicas e pesquisas acadêmicas (1982-2018)
(Universidade Federal de São Carlos, 2022-10-28) Martins, Gabriela Luchesi; Reyes, Claudia Raimundo; https://lattes.cnpq.br/5187942717120318; https://orcid.org/0000-0002-0692-3020; https://lattes.cnpq.br/8321641294556789; https://orcid.org/0000-0001-6835-177X
The present work has as its theme Freinet Pedagogy and academic research (theses and dissertations), between 1982 and 2018, which address theory and practice in the classroom. Célestin Freinet believed that techniques and practices would change according to the social, historical, political and cultural issues of a given time. Based on this premise and our personal experience with this Pedagogy, we chose our research theme and arrived at the following question: what transformations in the teaching and learning process can be perceived in Brazilian academic research between 1982 and 2018, based on the Freinet Pedagogy, who use techniques and practices in the classroom, in Elementary School I? From this, we set the following objectives: to know the academic research on Freinet produced in Brazil; discriminate which researches involve freinetian techniques and practices in Elementary School I; and to analyze the transformations that occurred in academic research in the teaching and learning process of Freinet techniques and practices in Elementary School I. For data collection, we used a bibliographical review as a methodology, based on the analysis of academic works, with a search in the Database Data from the CAPES Portal. We categorize and organize the research in tables and graphs, finally we have 9 works that were found in those that involve the teaching and learning process in the classroom, in elementary school I and that bring as a theme the pedagogical practices, techniques and freinetian principles . We find in the post-2000 works the connection with Marxist-based theories – Freire, Vygostsky, Pacheco, Wallon – different from those prior to that period that had their focus on Freinet. It appears that the essence of Freinet Pedagogy, its principles, remain until today, like a seed that germinates and bears fruit, spreading, sprouting in fertile soil.