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0D and 2D nanomaterials based on Graphene quantum dots and MXenes: synthesis, characterization and application in sensors and supercapacitors
(Universidade Federal de São Carlos, 2023-10-20) Facure, Murilo Henrique Moreira; Corrêa, Daniel Souza; https://lattes.cnpq.br/0461451015026948; https://orcid.org/0000-0002-5592-0627; https://lattes.cnpq.br/4173216607463824; https://orcid.org/0000-0003-0858-0364
Graphene Quantum Dots (GQDs) are small fragments of one or a few layers of graphene with lateral dimensions inferior to 100 nm. GQDs present some characteristics similar to those of graphene, such as a high surface area/volume ratio and chemical stability. In addition, GQDs present a bandgap between their valence and electronic conduction bands. This bandgap gives rise to one of the most investigated properties of GQDs: their photoluminescence, which enables their application as luminescent sensors. In this sense, in the first work, hydrothermal syntheses of GQDs from graphene oxide (GO) were studied aiming at obtaining a material with greater photoluminescence intensity for application in luminescent sensors. The synthesis temperature, pH of the GO solution, and GO concentration were evaluated to optimize the quantum yield of GQDs. An optimized value of 8.9% was obtained. The influence of each parameter on the composition and properties of the GQDs was carried out from the physical-chemical characterization of the materials. The synthesized materials were used in the detection of Fe3+ ions in aqueous solutions by luminescence quenching, obtaining a detection limit of 0.136 M. Like GQDs, the discovery of a new class of materials known as MXenes was inspired by the discovery of graphene. MXenes are 2D materials, in which transition metal layers are interleaved with carbon and/or nitrogen layers. Such materials have demonstrated high energy storage capacity, being widely exploited in devices such as supercapacitors and batteries. However, the restacking of the MXene layers and the narrow potential window usually obtained limit the performance of these materials in such applications. In another work, nanodiamonds (NDs) were used to prevent the restacking of the MXene layers during its use as a supercapacitor electrode. The pillaring effect obtained with the NDs allowed a greater diffusion of protons between the layers of the MXene Ti3C2Tx, resulting in a capacitance of 235 F/g (561 F/cm3) when used in 3 M AlCl3 electrolyte. Furthermore, a wide potential window of 1.2 V could be used due to the reduced water activity in the electrolyte.
Bioprospecção de actinobactérias endofíticas com potencial antimicrobiano isoladas de Theobroma cacao
(Universidade Federal de São Carlos, 2023-10-20) Pinto, Lívia Freitas da; Nunes, Adriana Ribeiro Carneiro; https://lattes.cnpq.br/7533716053525477; https://orcid.org/0000-0003-1522-9871; Sousa, Cristina Paiva de; https://lattes.cnpq.br/9002619114161319; https://orcid.org/0000-0001-7151-5085; https://lattes.cnpq.br/2895704512929326; https://orcid.org/0000-0002-2899-0187
Actinobacteria constitute one of the largest bacterial phyla and are classified as Gram-positive bacteria, being ubiquitous in aquatic and terrestrial ecosystems. They are recognized for their ability to produce secondary metabolites with different functionalities, among which are bioactive compounds with antimicrobial activity. This study bioprospecting and identification of endophytic actinobacteria isolated from Theobroma cacao grown in the region of Paragominas, Pará. region of Paragominas, Pará, Brazil and evaluated the biotechnological potential of these strains in the production of antimicrobial agents. After isolation, it was possible to verify the presence of 11 distinct endophytic bacteria. bacteria. The identification of these isolates, determined by phenotypic analysis and molecular characterization, proved that 4 of the 11 belonged to the actinobacteria group, and these were classified at the level of Microbacterium (3 strains) and Curtobacterium (1 strain). The other isolates were characterized as Pseudomonas (2 strains), Bacillus (1 strain), Ralstonia (1 strain) and Methilobacterium (3 strains). The 4 strains from the Actinobacteria phylum were submitted to the antimicrobial activity evaluation test activity. All of them inhibited the growth of Staphylococcus aureus (inhibition halos diameters ranged from 2.3 to 3 cm), proving to be effective against this Gram-positive bacterium. However, they showed no activity against Escherichia coli.
Terapia ocupacional e cultura: sobrevoos sobre construções acadêmicas do campo
(Universidade Federal de São Carlos, 2023-10-20) Lavacca, Antonio Belforte; Silva, Carla Regina; https://lattes.cnpq.br/6417501858864106; https://orcid.org/0000-0002-7079-8340; https://lattes.cnpq.br/2410272740259858; https://orcid.org/0000-0002-1063-3392
This thesis presents dialogues between the fields of culture and occupational therapy. Initially, we conceptualize some ideas around understandings of culture. Next, we relate the theme of culture as present in the construction of Brazilian occupational therapy, its relations with the arts, the expansion of fields and actions based on engagement, commitment and political constructions. The thesis aimed to: Identify and analyze the possibilities of occupational therapy in the interface and with the culture; to map and analyze the knowledge and practices of occupational therapists that contribute to the reflections and possibilities of the field of occupational therapy and culture. Therefore, it sought to meet research groups and other groups of occupational therapists that establish relationships with culture. How do they dialogue? What are the prospects? What relationships do they establish? Afterwards, we invited people, researchers and representatives of groups and collectives. Thus, 13 interviews were carried out, based on a script produced for this purpose and, above all, dialogues based on trajectories, practices, reflections and other constructions. All interviews were transcribed and analyzed, as well as all ethical precepts of research with respected human beings. In this way, in the results we present the profile of each interviewee, and the thematic curation of the narratives was carried out, in which five major themes of debate in the field are highlighted: Cultural, Political and Law Accessibility, Aesthetic Experience, Corporeality and intersectional relationships Finally, the narratives represented the possibilities of practices and dialogues in the cultural field whose practices revealed relationships of multiple meanings and directions. New perspectives, new horizons, new directions and other perspectives are brought as a strengthening exercise for the future of practices and debates for the field and the possibilities of interface between culture and occupational therapy. It is more about thematic curatorship than classifications, thematic or comparative analyzes that express the potential and challenges of this construction.
Representação e recuperação da informação em campanhas de publicidade no Facebook ADS: estratégias e proposição de protocolos de descrição
(Universidade Federal de São Carlos, 2023-10-20) Miguel, Daniele Teixeira; Zafalon, Zaira Regina; https://lattes.cnpq.br/1584935790390793; https://orcid.org/0000-0002-4467-2138; https://lattes.cnpq.br/2102576973108056
This research investigates the representation and retrieval of information, specifically focusing on the construction of nomenclature for Facebook Ads media campaigns. The overall objective is to define protocols for describing media campaigns on Facebook Ads, with the aim of expanding reach in information retrieval mechanisms. This is an applied research that adopts a qualitative approach and exploratory objectives. The employed methodology includes bibliographic and documentary research, providing a robust and in-depth analysis of the topic. The study critically analyzes the lack of standardization in the definition of nomenclature for ads broadcasted on the Facebook Ads platform and how this interferes with efficient information retrieval. As a result, the research presents a concrete proposal for standardizing nomenclature, based on the concept of folksonomy. This proposal is specifically directed towards the areas of campaigns, ad groups, and ads within the Facebook Ads platform, offering a practical and effective solution to improve information retrieval in these areas.
Pandemia e exclusão social: rupturas sociais e projetos de vida de adolescentes brasileiros em cumprimento de medida socioeducativa de internação
(Universidade Federal de São Carlos, 2023-10-20) Sena, Bárbara Cristina Soares; Pessoa, Alex Sandro Gomes; https://lattes.cnpq.br/4333565964821090; https://orcid.org/0000-0002-9271-8575; https://lattes.cnpq.br/0561874210217062; https://orcid.org/0000-0002-0164-7004
The COVID-19 pandemic has heightened concerns about the conditions of socially vulnerable adolescents in Brazil and around the world. Containment measures and the health, economic and social consequences increased the risks already experienced by this population. Therefore, the main objective of this research was to understand the impacts that the pandemic had with regard to social and relational ruptures caused by the COVID-19 pandemic in the lives of adolescents in situations of social exclusion, more specifically, adolescents fulfilling socio-educational measures of hospitalization. Furthermore, the aim was also to verify the influences and changes of the pandemic context on their life projects and future expectations. Based on the assumptions of the Bioecological Theory of Human Development, we sought to develop analyzes that made it possible to articulate the impact of the pandemic in the contexts of adolescents who were already experiencing situations of social exclusion and its consequences in the face of possible ruptures with significant people and spaces, as well as in your life projects. This was a qualitative, exploratory, descriptive study with a cross-sectional design. Twenty-two adolescents living in the five macro-regions of Brazil participated in the investigation, aged between 16 and 19 years old, male and undergoing a socio-educational hospitalization measure. For data collection, the following instruments were used: i) Questionnaire on the sociodemographic characterization of participants; ii) Life Project Questionnaire; and iii) Semi-structured Interview. The Thematic Analysis (TA) technique was used to analyze the data. The results indicate that the Covid-19 pandemic considerably impacted the social and relational bonds of adolescents who were hospitalized. There was an increase, specifically, of ruptures with school spaces, as difficulties already existed before the pandemic and these were aggravated by the way educational spaces were organized. But, at the same time, there was also a strengthening of these adolescents' family relationships, mainly due to the increased interaction made possible by the period of social isolation. Regarding life projects, the research revealed a positive perception among adolescents in identifying the presence of goals and expectations for the future. However, the context of the pandemic added even more difficulties to the reality of adolescents who were already experiencing situations of social exclusion, such as the absence of work and worsening socioeconomic difficulties. The thesis questions, in such a way, the uncritical and hegemonic look directed at the population investigated with regard to the topics covered. An individualizing conception of the factors involved in development can lead to biased analyzes and practices regarding important aspects for the present and future of these adolescents.