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Remoção fotoeletrocatalítica do antibiótico ciprofloxacina usando um fotoanodo baseado em hematita modificada com materiais de bismuto
(Universidade Federal de São Carlos, 2024-12-18) Feitosa, Maria Helena Alves; Moraes, Fernando Cruz de; https://lattes.cnpq.br/8597473049054728; https://orcid.org/0000-0002-1485-8003; https://lattes.cnpq.br/2168357554124780; https://orcid.org/0000-0003-2501-644X
Emerging contaminants are chemical substances or microorganisms that, although not yet widely regulated, have raised increasing concerns due to their potential environmental and public health impacts. From this perspective, this research addresses the environmental issues related to these contaminants and the risks they pose to various living organisms, highlighting the importance of developing analytical methods to investigate the degradation pathways of ciprofloxacin. The objective of this work was to synthesize nanostructured materials, characterize them and apply them in the fabrication of photoanodes for application in photoelectrocatalytic processes. The electrodes were characterized by electrochemical, morphological, structural and optical techniques. For this purpose, hematite films, bismuth-based materials and their respective composites were obtained in order to investigate their applicability in the photoelectrochemical degradation of ciprofloxacin. The optimized photoanode FTO/Fe2O3/BiOI@BiOBr was used as the working electrode in an electrochemical reactor with a volumetric capacity of 500 mL, containing ciprofloxacin at a concentration of 3.0 × 10–5 mol L–1, under constant application of a working potential of +2.0 V, with ultraviolet radiation of 9.0 W. Parameters such as pH, concentration of the supporting electrolyte, ciprofloxacin concentration, working potential and composition of the photoanode were evaluated. The photoanode revealed a degradation rate higher than 90 % and a mineralization rate of approximately 52 % after 1 hour of process. In parallel, mass spectrometry experiments revealed the formation of fourteen byproducts, allowing the proposal of a three-step degradation pathway. Therefore, the FTO/Fe2O3/BiOI@BiOBr photoanode proved to be an excellent catalytic material, presenting environmental relevance by promoting the efficient degradation of ciprofloxacin in one hour of process, with favorable energy expenditure.
Estudo de guias de onda com modificações estruturais para aplicações como sensor de índice de refração
(Universidade Federal de São Carlos, 2024-12-18) Pinheiro Neto, Otavio de Paiva; Barea, Luis Alberto Mijam; https://lattes.cnpq.br/7929868663210908; https://lattes.cnpq.br/7296268988601761
This final course project addressed integrated optical sensors exclusively based on waveguides, aiming to enhance the interaction of the guided mode's evanescent wave with the target analyte. Initially, structural modifications were introduced in the waveguides to optimize this interaction, inducing propagation losses and modulating the output power of the waveguide according to variations in the refractive index of the analyte. The interaction with the analyte was concentrated in a detection window, simplifying the complexity of optical sensors and reducing the high-resolution requirements of the equipment commonly used to measure resonant wavelength variations. Due to the complexity of the calculations involved, computational simulations were performed using the commercial software RSoft, specifically with the BeamPROP module, enabled by a partnership with the Research Laboratory in Devices (LPD) at the State University of Campinas (UNICAMP). The project also investigated the use of absorber materials, strategically positioned to modulate the interaction of the evanescent wave based on variations in the refractive index of the analyte. This method intensified the changes in the output power of the waveguide, facilitating the precise monitoring of refractive index variations. Finally, microfabrication processes were addressed to enable these optical sensors, culminating in the development of a fabrication roadmap and virtual lithographic masks. The results indicated the feasibility of developing highly sensitive and simpler-to-monitor sensors with potential for diverse applications, including the measurement of hemoglobin concentrations in human blood.
Futuro à vista: transição para a vida adulta de adolescentes e jovens adultos brasileiros com paralisia cerebral sob a ótica biopsicossocial
(Universidade Federal de São Carlos, 2024-12-18) Santana, Camila Araújo Santos; Rosenbaum, Peter; Campos, Ana Carolina de; https://lattes.cnpq.br/5292093208120940; https://lattes.cnpq.br/7986401363114609
This thesis has as its central theme the process of transition to adulthood for adolescents and young adults with cerebral palsy. Due to the state of evidence on the topic at a global and national level, different methodological approaches were adopted throughout the doctoral period, resulting in three articles. Article 1: Aimed to synthesize the literature regarding the components of the International Classification of Functioning, Disability and Health (ICF) that have been addressed, looking beyond body structures and functions, and to analyze who was evaluated in research on adolescents and young adults (AJA ) with cerebral palsy (CP) in the transition phase to adulthood. It was concluded from this scoping review including 86 studies that the constructs related to activity and participation are the main research focus of the studies available in the literature between 2014 and 2021 that explored factors related to the development of health, autonomy and participation, with more needed studies that focus on environmental factors. Teenagers and young adults are the main source of information and the perspectives of other key figures are also being considered. Article 2: This cross-sectional study aimed to describe the levels of autonomy in participation in ten areas of adult life and explore factors associated with autonomy in participation of young Brazilians with cerebral palsy (CP). 114 young people with CP participated in the study, and it was observed that autonomy in participation is in development or complete in most areas of life. Romantic relationships and sexuality were the areas with the lowest levels of autonomy, while rehabilitation and leisure presented high levels of autonomy. Levels of autonomy tended to increase along with greater perceived self-efficacy and age, with personal factors playing a central role in the acquisition of autonomy in participation during the transition to adulthood for young people with CP. Article 3: Aimed to understand the most relevant participation experiences for these young people, and to support the development of a questionnaire to explore these aspects with young people with CP transitioning to adulthood in a larger study. Using qualitative and participatory methodology, it was possible to develop a questionnaire containing 25 questions. The experiences lived and reported by young people were essential to identify specificities about the most relevant themes that supported the development of the questionnaire, and the partnership with them in research occurred in a dynamic and effective way. Based on these three studies, it was observed that a more comprehensive view of human development is necessary when we research, evaluate and monitor adolescents and young adults with cerebral palsy who are in the transition phase to adulthood. Your opinions about your own experiences and health condition should be considered as a priority whenever possible. Your environmental context must also be considered as a major influencer on your process of becoming an adult. Their acquisition of autonomy in participation can be increasingly supported and promoted as they grow, and their personal empowerment will also enable them to be more autonomous and to engage in diverse activities, including scientific research, and will also allow them to reach their participation potential and enjoy the best possible quality of life.
The order fulfillment problem in the textile industry: MIP models for service-levels constraints and integrated production-distribution problems
(Universidade Federal de São Carlos, 2024-12-18) Alves, Giovanna Abreu; Camargo, Victor Claudio Bento; https://lattes.cnpq.br/9844223635046284; https://orcid.org/0000-0001-9332-3025; Tavares Neto, Roberto Fernandes; https://lattes.cnpq.br/6954662222457389; https://orcid.org/0000-0002-4659-1745; https://lattes.cnpq.br/7295040840180666; https://orcid.org/0000-0002-9562-2755
In this work, we address the production planning problem by focusing on meeting orders in the textile industry and analyzing how mathematical programming can support decision-making. Aiming to characterize the textile industry in São Paulo, Brazil, we performed an exploratory survey with managers of textile industries in the state. The survey highlighted crucial factors for the competitiveness of the companies, such as customer relationship, quick response, and production scheduling. It also shows the lack of management information systems for production planning. Additionally, an extensive literature review further contextualizes these challenges within the scope of textile supply chain management, highlight areas where mathematical programming can be applied to address production planning problems in the textile sector. Based on the identified gaps, we propose two mixed integer programming models for production planning problems focusing on customer order fulfillment. The first model focuses on servicelevel and capacity utilization constraints within capacitated lot-sizing problems, exploring the effects of these constraints on key performance indicators such as delay times, throughput, and capacity utilization. The second model supports integrated production and distribution decisions, demonstrating its advantages over hierarchical models through a comparative analysis. We also proposed an Adaptive Large Neighborhood Search (ALNS) heuristic to solve the integrated model in lower computational times, offering insights into the operational complexities of textile manufacturing.
Nova metodologia dos rankings Times Higher Education e a pontuação em citações das universidades da América Latina
(Universidade Federal de São Carlos, 2024-12-18) Cangiani, Maria Laura Machado; Faria, Leandro Innocentini Lopes de; https://lattes.cnpq.br/0767710394930118; https://orcid.org/0000-0002-8369-1315; https://lattes.cnpq.br/5263317427243364; https://orcid.org/0009-0001-8095-7835
Rankings are ubiquitous in monitoring university performance, but there is controversy about their procedures. One intriguing fact is the divergence observed between the overall position, research position and citation position occupied by the universities evaluated by THE Latin America University Rankings: the universities best evaluated by this ranking are also well evaluated in research, but they are not the best evaluated in citation. This divergence is due to the methodology for scoring universities in the Citation indicator, based on Field-Weighted Citation Impact and which has undergone recent adjustments, including the introduction of the Research Strength metric, aiming to better represent the performance of universities in citation. This research aims to evaluate the new methodology of the Times Higher Education by simulating the calculation of Research Strength. The research is configured as exploratory, quantitative and comparative in that it seeks to expand knowledge about the impact caused by a recently implemented methodology, using position and score data from the rankings, as well as publication and citation data, in addition to its own calculations, comparing the performance of several universities. Data from THE Latin America University Rankings 2022 and the Scival Platform were used. High correlations were found between the Overall, Teaching and Research Scores and low correlation between the Overall and Citation Scores and between Citation Score and Field-Weighted Citation Impact. The simulation carried out among the top 100 universities in THE Latin America University Rankings 2022, using Research Strength, showed that this metric may have the opposite effect to that expected, favoring the best citation performance of universities with many publications with many co-authors.
Diversificação metabólica no fungo Talaromyces sp. usando indutores abióticos
(Universidade Federal de São Carlos, 2024-12-18) Gomes, Nayara de Freitas; Rodrigues Filho, Edson; https://lattes.cnpq.br/3667941735597178; https://lattes.cnpq.br/2214995806556729
We investigated the metabolic diversification of Talaromyces sp. under the influence of individual and combined abiotic factors, particularly UV-A radiation and metal cations. To understand the impact of these factors on metabolite production, we carried out experiments under diverse cultivation conditions. Initially, we examined non-volatile and volatile organic compounds (VOC’s) by cultivating the fungus on solid rice and liquid Czapek media, with and without the supplementation of manganese (Mn²⁺) and cobalt (Co²⁺) cations. Subsequently, we conducted cultivations under the following conditions: (1) solid rice medium, with and without metal cation supplementation, (2) liquid Czapek medium, supplemented with Mn²⁺, Co²⁺, and Fe²⁺, both in the presence and absence of UV-A light and (3) semi-solid potato dextrose agar (PDA) medium, with and without exposure to UV-A light. The VOCs were analyzed using gas chromatography coupled with mass spectrometry, and the extracts from cultivations (1), (2), and (3) were analyzed by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry. Obtained data were processed using the MetaboAnalyst, MZmine, and GNPS (Global Natural Products Social Molecular Networking) platforms. During the cultivations, growth inhibition of the fungus was observed in the liquid Czapek medium supplemented with Co²⁺, whereas it was not observed in the presence of Mn²⁺. On the other hand, cultivation on solid rice medium exhibited diversified production of metabolites, including sesquiterpenes and fatty acids. The Principal Component Analysis (PCA) of the VOCs revealed distinct clustering in the chemical profiles, which correlates with the modulation of metabolite production due to cation supplementation. In cultivations with Co²⁺ and Mn²⁺, the molecular networks generated by GNPS showed a drastic decrease in the number of nodes, associated with a reduction in compound production; however, sesquiterpenes and fatty acids were annotated, indicating that the biosynthetic pathway for these classes remained active. The extracts from the cultivation of Talaromyces sp. on rice with distilled water, cobalt chloride (30 mmol), and manganese chloride (250 mmol), analyzed by mass spectrometry and processed through GNPS, revealed the presence of the meroterpenes austin, dehydroaustin, and acetoxydehydroaustin. Confirmation of these compounds was achieved through isolation via reverse-phase high- performance liquid chromatography and characterization by ¹H and ¹³C nuclear magnetic resonance. In the cultivation of Talaromyces sp. on PDA under UV-A light, we observed the presence of compounds not detected in cultures kept in the absence of UV-A light. PCA analysis showed that the irradiated extracts formed distinct clusters, further supporting evidence of the influence of light on the biosynthesis of secondary metabolites. The presence of meroterpenes was also observed in the cultures grown in Czapek medium under light exposure and with metal supplementation, based on the metabolic profile analysis. Additionally, molecular networking indicated a metabolic cluster containing products derived from L-tyrosine, such as N-acetyltyramine and p- aminophenol. The VOC’s and obtained extracts were subjected to biological assays to evaluate their antibacterial activity against Staphylococcus aureus and Escherichia coli, revealing selective activity against S. aureus, albeit at a moderate level.
Abordagem contextual paramétrica na análise de componentes principais
(Universidade Federal de São Carlos, 2024-12-18) Nakao, Eduardo Kazuo; Levada, Alexandre Luis Magalhães; https://lattes.cnpq.br/3341441596395463; https://lattes.cnpq.br/8552980487205959
In unsupervised analysis, the quality of a dispersion can be measured by the relation between the proximity of the samples of one class, and the inter-classes separation. One relevant task in this context is characterized by the mapping of a dispersion X into a new X' of higher quality, which preserves the neighborhood relationships. The PCA is a mapping method that possesses as property the maintenance of the samples global maximum scatter. Such property can generate both higher inter-class separation and higher intra-class spreads. The intra-class spread can be diminished by the smoothing of the influence fo samples that are distant from their cluster. Such smoothing can be obtained by the substitution of the proximity calculation between individual samples by a similarity measure between contexts. From this idea, a PCA modification is proposed where the contextual information is extracted from the neighborhood graph, and a feature values set is mapped to a parametric statistical distribution, allowing that a distribution divergence can be used as similarity measure. Previous experiments with a limited set of divergences indicate that the approach is able to produce superior results than several existing mapping methods. The first investigation line of this work employ a larger set of divergences in order to verify the approach robustness. The obtained results show that, for a large set of divergences, the proposal shows a superior performance than all other compared algorithms in the majority of the tested sample set. The second investigation line of the work is defined by the verification of existence of relationship between the performance of a divergence and the properties of a sample set. From the study is possible to infer that higher value divergences tend to generate better dispersions for higher class quantities.