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Contribution of homogeneous and heterogeneous processes to the activation of Peroxymonosulfate using cobalt magnetic ferrite
(Universidade Federal de São Carlos, 2024-04-29) Broterson, Yoisel Bueno ; Aquino, José Mario de; https://lattes.cnpq.br/8847710280926769; https://lattes.cnpq.br/5588787534722285
The catalytic process (c-AOP), which utilizes metal oxides (or another type of material) to activate various oxidants such as hydrogen peroxide (H2O2), peroxydisulfate (PDS, S2O82–), and peroxymonosulfate (PMS, HSO5–), among others, constitutes one of the advanced oxidative processes (AOP) that can effectively treat surface and supply waters contaminated by synthetic organic compounds. In particular, magnetic ferrites have the advantage of being reusable and easily separated from the reaction medium. However, there is a significant gap in the literature regarding the participation/action of ions leached from those metal oxides in the oxidant activation process, as well as the study of the surface modifications that occur in the oxides after use. Therefore, the objective of the present work was to elucidate the role of cobalt magnetic ferrite (CoFe2O4), and Co(II) ions added to the reaction mixture, in the in situ chemical oxidation (ISCO) of the insecticide imidacloprid (IMD) using peroxymonosulfate (PMS), as well as the surface effects on ferrite resulting from the ISCO process. For this purpose, CoFe2O4 was synthesized using the sol-gel (SG) and co-precipitation (Cpt) methods, followed by calcination in a muffle furnace (400 ºC and 700 ºC) for 1 h, and the materials obtained were characterized as-prepared (AsP) and, after use in the pollutant degradation tests (Us). The application of CoFe2O4 for the in situ activation of PMS involved studying the catalyst dosage and PMS concentration, the effect of phosphate buffer and pH, as well as different aqueous matrices. Based on the results obtained, low concentrations of CoFe2O4 (0.125 g L–1) and PMS (500 µmol L–1) are sufficient for the complete oxidation of IMD. Furthermore, it was observed that even small concentrations (in the order of µg L–1) of the Co(II) ion also resulted in the complete oxidation of the pollutant, with pH correction and monitoring of the reaction medium contributing to this process. This finding contributes to the understanding of why all synthesized materials exhibit similar rates of IMD oxidation. Some attempts to prevent the leaching of Co(II) ions were carried out; however, they were not successful. Analysis by liquid chromatography coupled to mass spectrometry allowed the identification of only 5 intermediates, starting from IMD, whose main structural modifications were due to ruptures in the imidazolidine ring and/or successive hydroxylation reactions. As expected, the main reactive oxygen species identified were hydroxyl (HO●) and sulfate (SO4●–) radicals, and the non-radical singlet oxygen (1O2). The latter species led to high levels of IMD oxidation, even in a complex aqueous matrix such as simulated municipal wastewater (SMWW), albeit with an order of magnitude decrease in the rate of IMD oxidation. Finally, a mechanism for PMS activation by solid and Co(II) ions was proposed based on the materials tested and data obtained.
Macroinvertebrados aquáticos da região Andino- Amazônica: paisagem fluvial, diversidade taxonômica e diversidade funcional
(Universidade Federal de São Carlos, 2024-04-29) Garaviz, Jhonatan Gutiérrez; Pelaéz-Rodríguez, Marlon; https://lattes.cnpq.br/6765247167719129; https://orcid.org/0000-0002-3607-8155; Rocha, Odete; https://lattes.cnpq.br/7577441794992601; https://orcid.org/0000-0002-0798-3316; https://lattes.cnpq.br/3524879178514703; https://orcid.org/0000-0002-6843-146X
The Andean-Amazonian region of the Caquetá department is renowned for hosting a vast biodiversity of terrestrial and aquatic organisms. However, in recent years, this region has experienced various anthropogenic impacts, primarily associated with deforestation, most evident in the lowlands. Additionally, this has led to significant concerns over the loss of connectivity between the Colombian Amazon and the eastern Andes Mountain range. This prompted us to study the riverscape associated with different lotic ecosystems to understand their regional dynamics and how this may influence the assembly of aquatic macroinvertebrates. We established three study zones: the Andes, the Transition, and the Amazonia, defining ten sampling stations. At each study site, we characterized the different components of the riverscape. In addition, we collected samples of aquatic macroinvertebrates using a multi-habitat methodology. For data analysis, we estimated taxonomic and functional alpha and beta diversity. We implemented a Redundancy Analysis to identify environmental variables that predict the composition and beta diversity of aquatic macroinvertebrates, and we developed a generalized linear model linking the richness and abundance of the Odonata order to altitude, latitude, and longitude (regional scale). Our results revealed a successional process of various environmental variables from the Andean region towards the Amazon, also highlighting a pattern of environmental deterioration that increases from the higher parts of the region to the lowlands. Moreover, these variables act as crucial environmental filters in the establishment of the community of aquatic macroinvertebrates and the Ephemeroptera order on a local scale and, from a regional perspective, in the Odonata order, which also serves as a bioindicator group for the fragmentation of riparian forests. Our findings provide valuable insights into the dynamics of the riverscape between the Andes and the Amazonia in Caquetá. Additionally, we have established new taxonomic records and diversity estimates, which could be vital for adequately using and managing natural resources in the region. These will serve as a future reference for vulnerability analysis related to the loss of connectivity between the study areas.
Licenciatura em música, ações afirmativas e diretrizes nacionais curriculares para a educação das relações étnico-raciais: o caso da UFSCAR e da UFRB
(Universidade Federal de São Carlos, 2024-04-29) Melo, Luísa Maria Matos de; Rodrigues, Tatiane Cosentino; https://lattes.cnpq.br/8361431964064731; https://lattes.cnpq.br/9436974023888782
This study aimed to investigate how the Bachelor of Music Education programs at two different Brazilian federal universities from different regions have been adapting, within the curricular scope, to the demands raised by the National Curricular Guidelines for Ethnic-Racial Relations Education (DCNs ERER). The proposal was to analyze the curricula and syllabi of the mentioned courses regarding the integration of themes related to ethnic-racial relations, as well as to understand the perception of students and graduates regarding this integration. This research involved a qualitative exploratory perspective, utilizing documentary and bibliographical analysis, in addition to semi-structured interviews. From the analysis of the Course Pedagogical Projects of the Federal University of Recôncavo da Bahia (UFRB) and the Federal University of São Carlos (UFSCar), it is also possible to obtain a more comprehensive overview of the influence of the different contexts in which they are inserted in the design of the curricula in question. Juxtaposing the data gleaned from the curricular analysis with the data procured from student interviews reveals a discrepancy between the propositions outlined in the documents and the students' perceptions of their implementation. Generally, the hypotheses suggest that curricula tend to incorporate the overarching principles of regulations, rather than the specific details, in most instances.
Considerações e possíveis soluções para o problema da estimação do mínimo populacional com aplicações em dados de terremotos
(Universidade Federal de São Carlos, 2024-04-29) Saldanha, Matheus Henrique Junqueira; Suzuki, Adriano Kamimura; https://lattes.cnpq.br/4579497412852854; https://lattes.cnpq.br/2301154612725391
A myriad of physical, biological and other phenomena are better modeled with semi-infinite distribution families, in which case not knowing the populational minimum becomes a hassle when performing parametric inference. This problem has not been directly discussed in the literature thus far, but it is straightforward to devise a maximum likelihood solution (denoted hereafter as ``pure MLE''), and endpoint estimators proposed in the literature could also be used. Although endpoint estimators are usually evaluated according to their bias and variance, in this project we argue that these are not adequate metrics, so we discuss and use alternatives. We then propose some solutions of our own, some of them aiming to achieve simplicity in terms of their computational cost, and one method (what we call ``maximum likelihood estimation with parameter-dependent support,'' or MLEPDS) where we estimate the population minimum indirectly, by maximizing a modified likelihood function $L(\cdot \mid \vec{\theta})$ that shifts the sample by a certain amount depending on $\vec{\theta}$. Experiments demonstrate that the proposed MLEPDS method outperforms both the pure MLE method as well as the approaches that use endpoint estimators proposed in the literature. In particular, our method offers significantly better results in smaller samples, which will surely be of use to many practitioners out there who have to work with limited data. The dissertation is concluded with an application of the proposed MLEPDS method to predict the maximum magnitude of earthquakes. The probability distribution of earthquake magnitudes is subject to a lot of discussion in the literature; Kijko (2004) describes a few options, which we modify appropriately for use in the MLEPDS method, with which we estimate maximum magnitudes. The regions of Japan, New Zealand, Balkan peninsula and worldwide are analyzed. Experiments show that our method overall gives higher estimates for the maximum magnitude than two other methods inspired by the literature, and also displays an apparent sensitivity in the year-by-year analysis, indicating that it manages to better capture and understand the underlying changes in seismic activity.
Desamparo: uma análise a partir das primeiras publicações psicanalíticas
(Universidade Federal de São Carlos, 2024-04-29) Washimi, Micaela Arisa; Maniakas, Georgina Carolina Oliveira Faneco; https://lattes.cnpq.br/1207794266426572; https://lattes.cnpq.br/1197118687819203; https://orcid.org/0000-0002-3138-3396
The term chosen in Brazilian Portuguese for the German word Hilflosigkeit, used by Freud since his early psychoanalytic publications, is "helplessness." In the reading of Freud's work, helplessness can be approached from various perspectives, which maintain certain similarities but differ in the way they emphasize specific aspects originating from different writings of Freud, to outline a concept of helplessness that is distinctly psychoanalytic. In this sense, this work sought to reconstruct the history of the use of the term helplessness in Freud's production, focusing on the early psychoanalytic publications (1892-1900), considered crucial for the development of Psychoanalysis. Its main objective was to analyze the texts from this period, seeking to understand the meaning attributed to the term in each of them, highlighting differences and similarities. For this purpose, a bibliographic survey was conducted, delimiting the productions in which Freud uses the terms Hilflosigkeit and hilflos, along with their possible variations. The works found in this bibliographic research served as guides for the readings and analyses carried out. It aimed to demonstrate that the constitutive elements of the concept of helplessness are already present in Freud's early writings; however, their integration depends on the development of other notions, such as the introduction of narcissism and the death drive, as well as the establishment of the second topic and the theory of angst. The exposition sought to highlight the ubiquity of the term helplessness in Freudian theory, emphasizing the difficulty of circumscribing it and the extent of its consequences for the psyche.