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Função sexual de mulheres com Fibromialgia
(Universidade Federal de São Carlos, 2023-10-19)
Silva, Rafaela de Melo
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Bernardes, Ana Paula Magalhães Resende
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https://lattes.cnpq.br/7497705995430245
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Serrão, Paula Regina Mendes da Silva
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https://lattes.cnpq.br/2917658715637353
Sexuality is an integral part of the individual, and is influenced by physical and psychological factors. Fibromyalgia is a central sensitization syndrome that mainly affects women and the clinical condition involves the presence of pain, anxiety, depression, low self-esteem, and these factors can negatively influence the sexual function of this population. It is essential to deepen knowledge in this area in view of the impact of sexual dysfunction on the quality of life and well-being of women with fibromyalgia. Study 1: The aim of the study was to investigate the relationship between sexual function and central sensitization in women with Fibromyalgia. This is a cross-sectional observational study. An online questionnaire was used for data collection. The questionnaire consisted of 85 questions, including questions to assess female sexual response (Female Sexual Function Index), assessment of central sensitization (Central Sensitization Inventory) and assessment of the impact of Fibromyalgia (Fibromyalgia Impact Questionnaire). 337 participants were included, 75.7% of women had sexual dysfunction. Furthermore, the results showed an association between sexual dysfunction and central sensitization. In conclusion, the results showed that there is a high prevalence of sexual dysfunction among women with Fibromyalgia, with a positive association between sexual dysfunction and central sensitization, with desire being the most affected domain. Study 2: the objective of the study was to evaluate the influence of anxiety and depression on the sexuality of Brazilian women with Fibromyalgia, for this, a cross-sectional observational study was carried out through an online questionnaire that evaluated female sexual response (Female Sexual Function Index), anxiety and depression (Hospital Anxiety and Depression Scale). A total of 255 women with sexual dysfunction were included in the study, most of them had moderate alteration related to depression (39.6%) and severe alteration related to anxiety (43.5%). Furthermore, the results showed that anxiety and depression are associated with sexual dysfunction. It is concluded that sexual dysfunction among Brazilian women with Fibromyalgia is associated with anxiety and depression, and it is essential that a screening of sexual dysfunction be carried out among patients with depressive symptoms and who have Fibromyalgia, so that an integral approach is carried out, in order to improve their quality of life.
Bioprospecção de actinobactérias endofíticas com potencial antimicrobiano isoladas de Theobroma cacao
(Universidade Federal de São Carlos, 2023-10-20)
Pinto, Lívia Freitas da
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Nunes, Adriana Ribeiro Carneiro
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https://lattes.cnpq.br/7533716053525477
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https://orcid.org/0000-0003-1522-9871
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Sousa, Cristina Paiva de
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.
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
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Corrêa, Daniel Souza
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https://lattes.cnpq.br/0461451015026948
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https://orcid.org/0000-0002-5592-0627
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https://lattes.cnpq.br/4173216607463824
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.
Terapia ocupacional e cultura: sobrevoos sobre construções acadêmicas do campo
(Universidade Federal de São Carlos, 2023-10-20)
Lavacca, Antonio Belforte
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Silva, Carla Regina
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https://lattes.cnpq.br/6417501858864106
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https://orcid.org/0000-0002-7079-8340
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https://lattes.cnpq.br/2410272740259858
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
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Zafalon, Zaira Regina
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https://lattes.cnpq.br/1584935790390793
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https://orcid.org/0000-0002-4467-2138
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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
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Pessoa, Alex Sandro Gomes
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https://lattes.cnpq.br/4333565964821090
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https://orcid.org/0000-0002-9271-8575
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https://lattes.cnpq.br/0561874210217062
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.
Produção de plásticos biodegradáveis à base de queratina extraída de penas de frango por rotas verdes
(Universidade Federal de São Carlos, 2023-10-23)
Vanderlei, Rafael Marques
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Moreira, Francys Kley Vieira
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https://lattes.cnpq.br/7156680316782417
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https://orcid.org/0000-0001-6368-3177
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Mattoso, Luiz Henrique Capparelli
Chicken feather is a by-product widely generated by the poultry agroindustry. However, its large-scale production and the challenges associated with waste management raise substantial concerns about its environmental impacts. Chicken feathers are predominantly composed of keratin, a protein that can be potentially valued towards new biodegradable materials with desirable physical properties for various applications. Focusing on this major objective, in this doctoral thesis, keratin was extracted from industrial chicken feather waste through sulfitolysis, followed by recovery using various precipitating agents: HCl, citric acid, NaCl, and acetone. This approach enabled the extraction of keratin in a dialysis-free, fast, and scalable way, using low-cost and non-toxic reagents, with emphasis on the acetone precipitation for which a recovery yield of 80% was obtained. Life cycle assessment outlined the main environmental hotspots in the keratin production, and a circular economy concept was studied to mitigate its environmental impacts. Chemical analysis revealed that the disulfide bonds present in keratin were converted into S-sulfocysteine, facilitating the keratin processing by thermo-molding. Transparent and water-insoluble thermoplastic films were produced with desirable properties for packaging applications, for example. The precipitating agents had direct implications on the distribution of molar mass, morphology, and hydrophobicity of the keratin films. These characteristics allowed obtaining films with a range of mechanical properties, from rigid films, with an elastic modulus above 400 MPa, to films with elongation at break as larger as 70%, for a tensile strength around 10 MPa. This thesis shows the potential for valuing chicken feather waste in the development of biodegradable keratin-based materials with reduced environmental footprints.
Uso de geoprocessamento para caracterização dos aspectos físicos, uso da terra e diagnóstico ambiental no município de Campina Do Monte Alegre (SP).
(Universidade Federal de São Carlos, 2023-10-24)
Carvalho, Giovana Costa
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Toledo, André Marcondes Andrade
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https://lattes.cnpq.br/1920147531988000
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https://lattes.cnpq.br/1064695459454037
The purpose of this research was to employ geoprocessing to analyze the physical aspects and land use to diagnose the environment in areas of permanent preservation (APPs) located in the municipality of Campina do Monte Alegre (SP). The study comprises the following stages: initially, the collection of data relating to the area under study, including planialtimetric maps (scale 1:10,000) and remote sensing products. Then the data was processed, using QGIS 3.32 software, detailing the physical aspects, the land use, in addition to demarcating and qualifying APPs in accordance with Law 12,651/2012. The final environmental diagnosis, overlapping the areas covered with native vegetation current with permanent preservation areas, it was found that the southern region of The municipality presents greater vulnerability with 39% deforested. Confirming thus, the need to recover native vegetation on site.
Sobrevivência de Dalbulus maidis em plantas hospedeiras alternativas na entressafra de milho
(Universidade Federal de São Carlos, 2023-10-24)
Arcangeli, Geovana Alves
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Marques, Rodrigo Neves
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https://lattes.cnpq.br/8945237946471247
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Gazaffi, Rodrigo
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https://lattes.cnpq.br/4506894662453338
Corn plays a fundamental role in Brazil and globally, being an essential crop for both human and animal nutrition. Furthermore, it serves as an essential raw material for the production of a variety of products, including beverages, fuels, polymers and others. However, several factors can influence corn productivity, such as soil, climate, cultivar, cultural practices and management of pests, diseases and weeds. This scenario becomes even more challenging with the second harvest or 'safrinha' which can contribute to the permanence of hosts in favorable conditions in the field, this can provide a greater incidence of pests and/or diseases caused by insect vectors, such as Dalbulus maidis (corn leafhopper). Studies regarding the survival capacity of the corn leafhopper on alternative host plant species, that is, species that can serve as shelter and/or food during the off-season, are still scarce. In this context, it is essential to identify possible host plants and determine insect vector management to minimize losses attributed to the corn leafhopper. The objective of this work was to evaluate the survival and development of corn leafhoppers on plants. Weed species were selected because they have a similar botanical classification to corn or due to their common occurrence in corn fields. For survival tests, two tests were carried out: on groups of plants and on individual plants, where the survival, oviposition and “bridge” of insects were evaluated. Survival assessments were carried out daily after the leafhoppers were confined in cages until all insects died. Oviposition assessments were carried out seven days after infestation. To do this, the leaves were detached from the plants and cut into smaller sizes to count the eggs using a stereoscopic microscope. The existence of several species of weeds can provide refuge and food, prolonging longevity, at least for a part of the leafhopper population. It is likely that, in agricultural environments, these weeds play a role in harboring populations of migrating leafhoppers from recently harvested corn fields, thus ensuring the survival of some of these insects until the emergence of new seedlings in the area. However, it is a fact that corn plants play a very important role in the survival of Dalbulus maidis in crops, and the presence of volunteer corn plants, staggered, late and continuous plantings can play a fundamental role in the population increase observed in recent harvests. Considering the data obtained, weeds are of marginal importance in maintaining Dalbulus maidis populations.
#juntospelolivro: discursos e práticas de promoção do livro e da leitura em tempos de crise política e de pandemia da COVID-19
(Universidade Federal de São Carlos, 2023-10-24)
Mariano, Laura Andreoli
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Ferreira, Luzmara Curcino
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https://lattes.cnpq.br/4849994635754652
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https://orcid.org/0000-0003-3555-1446
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https://lattes.cnpq.br/2442735951407047
En esta disertación, a través de un meticuloso análisis de los enunciados obtenidos de la campaña #juntospelolivro, ampliamente difundida en Instagram, llevamos a cabo un estudio de su conexión con ciertos discursos acerca del libro y la lectura. La singularidad de los enunciados de esta campaña, que tiene como objetivo promover la lectura y el libro, se enmarca en el contexto de los desafíos políticos y de salud que enfrentó Brasil entre 2018 y 2022. Para esta investigación, nos apoyamos en los principios teóricos de los estudios del discurso según Michel Foucault (1970; 1987) y Possenti (1999; 2001); además, consideramos las perspectivas de los estudios históricos y culturales sobre el libro y la lectura según Roger Chartier (1998, 1999, 2002; 2003), Abreu (2001a; 2001b; 2006), Barzotto & Britto (1998), Curcino (2010; 2016; 2018; 2019; 2020), entre otros notorios autores. Nuestro análisis se centró en la identificación de patrones temáticos recurrentes en estos enunciados de la campaña, junto con la descripción de aspectos de su expresión lingüística, en combinación con elementos visuales. Lo que distingue esta campaña de las muchas otras contemporáneas de promoción de la lectura y el libro en las redes sociales es la preeminencia de dos temas: las funciones terapéuticas (contra el aburrimiento y la ansiedad) de la lectura y el libro, y su dimensión política, ya sea como forma de resistencia a las políticas gubernamentales en curso que afectan al sector librero, ya sea como un medio para combatir la desinformación que circulaba en ese momento. Entre los resultados de nuestro análisis, cabe destacar la frecuencia y especificidad de las referencias a los beneficios terapéuticos de la lectura y el libro, como una práctica para contrarrestar las consecuencias psicológicas y emocionales del distanciamiento social y el miedo generado por la pandemia de COVID-19. Para ello, también nos apoyamos en los estudios de Biblioterapia, buscando su integración con la Historia de la lectura. En relación con el segundo grupo temático más relevante de enunciados en nuestra investigación, el relacionado con la política, observamos especialmente cuánto se atribuyó a esta práctica el poder de proteger a los lectores contra las noticias falsas, los discursos de odio y las falsedades. Tanto en las publicaciones como en los comentarios a las mismas, observamos formas de autorrepresentación como lectores, que se expresaban con un gran orgullo. Así, tanto los autores de los textos de esta campaña como aquellos que los leyeron y comentaron pudieron compartir su orgullo de ser lectores, lo cual se manifestó de manera notable en la formulación de estos enunciados.
O luxo na hotelaria no Brasil: panoramas e a atuação da associação Relais & Châteaux
(Universidade Federal de São Carlos, 2023-10-25)
Barbosa, Iury Eduardo Lobato
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Silva, Carlos Henrique Costa da
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https://lattes.cnpq.br/5444248390841543
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https://lattes.cnpq.br/5105487056408797
This master's dissertation examines the role of the Relais & Châteaux association in the current Brazilian luxury tourism market. The analysis focuses on the interplay between the location and operation of hotels affiliated with this association and the Brazilian regional context. The objective is to comprehend the influence of luxury hotels in Brazil and evaluate the concept of luxury within these ventures, considering geographical factors in their locations. The study adopts a qualitative approach, grounded in a literature review to establish the theoretical foundation and guide the research, as well as an analysis of secondary sources from entities related to Luxury Tourism, both in Brazil and internationally. The data analysis follows the perspective of historical-dialectical materialism, critically interpreting the data and reflecting on the empirical reality, allowing a comprehensive and in-depth understanding of luxury hospitality in the Brazilian context. It becomes evident that Brazil holds a peripheral position in the global luxury hotel landscape, even with the current influx of international capital through the establishment of new hotel ventures. Furthermore, luxury hotels in Brazil are predominantly concentrated in coastal areas, reinforcing the national identity oriented towards Beach and Sun Tourism and in prominent financial districts, reflecting the influence of capital in shaping regions of higher centrality in spatial production. Additionally, the significant role of independent hotel associations is highlighted in positioning their members in the global landscape of luxury establishments, expanding the visibility of these ventures beyond the regional scope.
Comportamento de alvenaria estrutural com junta fina de argamassa polimérica
(Universidade Federal de São Carlos, 2023-10-26)
Parsekian, Guilherme Aris
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Sipp, Gustavo
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https://lattes.cnpq.br/7798651726059215
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https://orcid.org/0000-0002-5939-2032
Programas internacionais de transição pós-escolar para pessoas com deficiência intelectual desenvolvidos na universidade: uma revisão de escopo
(Universidade Federal de São Carlos, 2023-10-26)
Leite, Graciliana Garcia
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Campos, Juliane Aparecida de Paula Perez
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https://lattes.cnpq.br/3169299095370522
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https://orcid.org/0000-0003-0789-808X
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https://lattes.cnpq.br/8318458556808830
Young people go through the important experience of transitions as they move into independent adulthood. The literature highlights that young people with intellectual disabilities generally perform worse in aspects of adult life, such as education, work, independent living, among others, when compared to a group without disabilities. From this perspective, post-secondary transition programs can help develop skills and abilities to increase the likelihood of success in independent adult life. Considering the Brazilian reality, in which there is a shortage of these programs, it is necessary to better understand the scenario from other perspectives. Therefore, this paper aims to: (a) characterise the international view on post-secondary transition programs, in the university context, for people with intellectual disabilities, taking as its starting point the United Nations Convention on the Rights of Persons with Intellectual Disabilities; (b) identify the skills and areas addressed in these programs and the effects on the lives of people with intellectual disabilities; (c) analyse the implications of these programs on people with intellectual disabilities in the university context, through a scoping review, taking as a reference the period from January 2006 to December 2022. The research included online databases such as Academic Search Premier ASP (EBSCO), Education Resource Information Center (Eric), PsycInfo (APA), CINAHL with Full Text (EBSCO), Web of Science Core Collection (Clarivate Analytics), and Scopus (Elsevier) and gray literature (Google Scholar, Global ETD Search, and DART-Europe E-thesis), as well as consulting the list of references of relevant studies. Data extraction from the studies was carried out by the main author and a reviewer using a previously developed and validated form. The synthesis of the extracted data focused on qualitative analyses, and the results were organised into thematic categories. The search strategy identified a total of 3,253 records, of which 34 searches were selected for inclusion and analysis. The results indicate that the majority of studies were published in the last 7 years (73.5%), in the United States and Spain. Most post-secondary transition programs last two years, predominantly inclusive types ones. The main areas the programs address are employment preparation and career development, academic development, self-determination skills, independent living, and socialising. Students who participated in the programs had higher employability rates, development of independent living skills, increased i and social skills. Post-secondary transition programs play a key role in the transition to independent adulthood for young people with intellectual disabilities. The set of skills taught along with the experience of participating in activities on a university campus with peers without disabilities constitute an opportunity that benefits preparation for independent adult life. Although there were some limitations to the information available in the collected data, this scoping review contributed to characterising post-secondary transition programs that act in the process of transition and preparation for independent adult life for people with intellectual disabilities.
Passivação de superfícies de perovskitas via dopagem substitucional
(Universidade Federal de São Carlos, 2023-10-26)
Torres, Israel Silva
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Lima, Matheus Paes
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https://lattes.cnpq.br/1835846543912999
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https://lattes.cnpq.br/7602145976843730
Humanity currently demands new energy sources to replace polluting energy sources and thus restructure the energy matrix in a sustainable manner. In this context, materials science plays a prominent role, as new materials enable the creation of sustainable and commercially viable energy sources. Perovskites have taken on a prominent role as light absorbers in photovoltaic cells by offering a low-cost alternative with superior optoelectronic properties, potentially surpassing current silicon-based technology. However, the application of these materials in solar energy conversion technology still faces various challenges in achieving competitive efficiency from a commercial perspective, and various enhancement strategies have been proposed. In particular, chemical surface passivation has shown promise in numerous experiments, but with many unexplored possibilities. In this doctoral thesis, we propose a novel surface passivation route through substitutional doping with trivalent cations. As a proof of concept, we apply our proposal to passivate the inorganic perovskite α-CsPbI3 on the (100) surface by replacing the Pb atoms occupying the surface octahedra with trivalent cations, namely In, Sb, and Bi. Our investigation employed ab initio simulation techniques based on density functional theory calculations.We found a preferential doping position in the surface octahedra with more than 0,35 eV/dopant compared to doping in deeper layers. We also observed a reduction in the band gap due to the addition of surface states, resulting in optical band gaps larger than the fundamental ones due to forbidden optical transitions (i.e., dark transitions). Among the dopants used, surface passivation with Bi atoms proved to be the most effective, with enhanced solar light absorption compared to the non-passivated α-CsPbI3 phase. Additionally, we varied the doping concentration and demonstrated the possibility of combining trivalent cations with other passivation mechanisms. Thus, our results for the specific case of α-CsPbI3 perovskite demonstrate the effectiveness of this doping proposal, pointing to a promising new route for improving the optoelectronic properties of perovskites in the field of photovoltaic applications.
Síntese e avaliação de ligante geopolimérico “one-part” para aplicação em cerâmicas refratárias
(Universidade Federal de São Carlos, 2023-10-27)
Reitmann, Bruno
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Bezerra, Breno Parente
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Luz, Ana Paula da
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https://lattes.cnpq.br/3470395641242374
Refractory ceramics play a pivotal role in the development and operation of strategic industrial processes worldwide. Due to their high versatility and excellent performance in extreme service conditions, refractory concretes containing calcium aluminate cement (CAC) as a binder are widely used. However, the search for alternative materials with a reduced environmental impact has been actively promoted in recent years, with geopolymers or inorganic polymers being potential substitutes for CAC in such ceramics. This study aimed to assess the feasibility of partially or completely replacing this cement with a "one-part" geopolymeric binder in the production of refractory ceramics. This binder was produced by mixing colloidal silica and NaOH solution, followed by drying at 200°C. The solid activator and precursor were chemically and physically characterized to understand their effect on the final ceramic properties. In a subsequent stage, a composition of the reference concrete matrix (containing only CAC as the binder) was prepared and analyzed, along with others containing different CAC contents and/or geopolymeric binders. The evolution of the physical and mechanical properties of the samples was studied after curing at 40°C and after firing at 800, 1000, and 1250°C to comprehend the impact of composition and thermal treatment on the final properties of the refractories. To achieve this, tests were conducted to determine porosity, apparent density, elastic modulus, dimensional variation, mineralogical composition, and mechanical strength of the test specimens produced. The results indicated limited geopolymerization during curing, resulting in low mechanical performance (<1 MPa) in the geopolymeric matrices, compared to matrices containing only CAC (7.2 MPa). Unlike the cement-containing system, the presence of hydrated phases was not identified in the geopolymer-bound compositions, with unreacted raw materials remaining in the microstructure. After firing, the geopolymeric compositions achieved a significant increase in the modulus of rupture, reaching values of around 41 MPa, surpassing the performance of the reference concrete. The effective sintering via a liquid phase in the microstructure, coupled with the formation of nepheline in the geopolymeric matrix, justifies this improved behavior of the produced ceramics. Therefore, the addition of the "one-part" geopolymer as an alternative binder to CAC in refractory formulations has proven to be an advantageous option in terms of the thermo-mechanical properties of the matrices produced. However, additional investigations are required to optimize its performance at low temperatures to ensure its broad applicability.
Modelos de branas em (5+1) dimensões e o espectro dos leptóns carregados
(Universidade Federal de São Carlos, 2023-10-27)
Gauy, Henrique Matheus
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Bernardini, Alex Eduardo de
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https://lattes.cnpq.br/5215976260958847
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https://orcid.org/0000-0001-7357-5479
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https://lattes.cnpq.br/1412367289023716
This manuscript is concerned with a mechanism for explaining the mass spectrum of the charged leptons within (5 + 1)-dimensional braneworlds. As a preliminary objective, new two co-dimensional thick braneworlds ought to be proposed and investigated. By considering a twofold-warp factor constructed from two intersecting warp factors and scalar fields that generates the extra dimension defect, an alternative bulk configuration is examined. With the brane localization thus driven by two crossing scalar fields, the possible solvable models obtained from such a two co-dimensional setup are systematically discussed. The obtained solutions are classified into two subsets, string and intersecting-like. The intersecting-like models are sorted in six different models organized into two subsets for which some of their physical properties are evaluated. For models I and II , in the first subset, Einstein equation solutions are rigidly defined, up to some arbitrary constant. For models III , IV , V and V I , in the second subset, an additional degree of freedom not constrained by Einstein equations is admitted. For all intersecting-like models, gravity and standard matter fields are shown to be localized in the vicinity of the brane. Finally, by studying the zero modes of leptons, which are localized by the inclusion of a non-trivial gauge field, over asymmetric versions of the classified braneworlds, one is able to model the masses of the electron, muon and tauon based on two parameters: the gauge field strength and the ratio between the sizes of the co-dimensions.
Análise da capacidade ao cisalhamento de paredes de contraventamento em alvenaria estrutural
(Universidade Federal de São Carlos, 2023-10-27)
Tinoco, Vinícius Navarro Varela
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Parsekian, Guilherme Aris
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https://lattes.cnpq.br/7798651726059215
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https://orcid.org/0000-0002-5939-2032
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https://lattes.cnpq.br/7222549742841551
Structural masonry systems are widely used in civil engineering due to the popularization of this construction method and potential savings. Several shear resistance equations are presented in the national and international normalization, and are used by structural engineers for analysis and design of this structures in the matter of lateral load structure resistance. It is necessary too to analyze and compare the different standards so that they can advance at the same pace as scientific knowledge, adding greater fidelity to the expected behavior, combining safety with economy. Therefore, it becomes essential to carry out a comparative study between the regulations and the most faithful predictions available of the behavior of the masonry structure responding to lateral loading that can, based on analysis, add to knowledge and design. Aiming at this issue, the present work seeks to present the main differences between the regulations for the resistant design of masonry structures, seeking to add, from the finite element study, to the prediction of the behavior of structural partially grouted masonry, under the design of different vertical regions between openings. For this, a parametric study was carried out based on what is most current in the literature regarding structural masonry modeling to form the database that will be used in the validation of this work. Among the five norms used, it was possible to perceive the following increasing order of resistant lateral load: Eurocode by diagonal compression (EN 1996-1-1, 2005); Canadian (CSA S304, 2014); Eurocode for slippage (new proposition of EN 1996-1-1); American (TMS 402/602, 2016); Australian (AS 3700, 2018) and Brazilian (NBR 16868-1, 2020), with the American being the closest to the modeling results and the reliable equation used. The flexo-compression was evaluated, with no significant difference in values between the standards. Based on the evaluation of other standards, a correction was also proposed to the Brazilian standard for the following factors to make it more conservative: net area of the masonry section; initial shear strength value; and decrease of the friction angle to be considered in the precompression portion. The proposal makes the standard more conservative and uses calculation factors that are already used in other standards.
Revisão bibliográfica: erros causados por raios cósmicos em dispositivos eletrônicos
(Universidade Federal de São Carlos, 2023-10-27)
Paulo, Isabella Moreira de Sousa
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Galeti, Helder Vinicius Avanço
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https://lattes.cnpq.br/3876752605313288
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https://orcid.org/0000-0002-5217-8367
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https://lattes.cnpq.br/4096799016142464
Cosmic rays, coming from outer space, can penetrate eletronic devices in order to change several characteristics such as functioning, performance and useful life. These particles are composed of an atomic nuclei, made up of ultra energetic protons and neutrons, that travel at high speeds towards the earth's surface, due to their high energy they can easily penetrate electrical and electronic components. These effects are easily found at higher altitudes, but can be observed at sea level on a smaller scale. With the advancement of microelectronics, the collision of these particles with electronic components generates a parasitic electrical charge that harms the operation of several devices, from memories, power electronics to relays and supercomputers. Thus, the purpose of this work is to report and provide an in-depth understanding of the influence of cosmic rays on the operation of electrical and electronic components, through a review of data available in the literature. The aim is to assess the impact on the operation of electronic components, electrical devices, and the advancement of new technologies.
Estudos do tratamento de águas residuárias do café usando coagulação e processos de oxidação avançada
(Universidade Federal de São Carlos, 2023-10-27)
Colpa, Poliana Coste e
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Bocchi, Nerilso
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https://lattes.cnpq.br/5930614700886481
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https://lattes.cnpq.br/8098870460818023
"STUDIES ON COFFEE WASTEWATER TREATMENT USING COAGULATION AND ADVANCED OXIDATION PROCESSES" Brazil leads global coffee production, accounting for more than one-third of the global production and playing a crucial role in the national economy. Post-harvest coffee bean management includes the wet processing method. The residues generated in this process are known as coffee wastewater (CWW). Therefore, it is necessary to study an alternative treatment for the CWW generated in the wet processing of coffee produced at IFSULDEMINAS, Campus Muzambinho. This work proposes the treatment of CWW using coagulation and Advanced Oxidation Processes (AOPs) as treatment methods. Initially, it was necessary to analyze some parameters of the CWW samples, such as: total solids mass concentrations, total suspended solids, total volatile solids, turbidity, pH, conductivity, Chemical Oxygen Demand (COD), and Total Organic Carbon (TOC). Due to high turbidity values (279.0 NTU) and COD (9067.0 mg L-1), it was adopted to always perform a coagulation pre-treatment using aluminum sulfate. This process removed about 97% of turbidity and 20% of COD from the CWW samples. For the electro-Fered-Fenton process, an electrochemical system was used (with a titanium anode coated with ruthenium dioxide and titanium dioxide (DSA – Dimensionally stable anode), and two AISI 304 stainless steel cathodes). In this treatment, it was possible to achieve a COD removal of approximately 78% and 95% turbidity removal. For the photo-electro-Fered-Fenton process, there was an efficiency of COD removal of around 86% and 95% turbidity removal. For comparison of treatment efficiency, the Fered-Fenton processes were used, obtaining a COD removal of about 83% and 95% turbidity removal, and photo-Fered-Fenton, where the COD and turbidity removal were 87% and 97%, respectively. These results indicate a better removal efficiency using the photo-Fered-Fenton treatment, which also shows a 70% TOC removal. Despite the slightly lower efficiency of the photo-electro-Fered-Fenton treatment, the photo-Fered-Fenton has a lower cost since it does not use electrical current and does not require an electrochemical system and electrodes, making the process simpler. With this treatment, the removal percentage recommended by current legislation is achieved, considering a minimum COD removal of 80%.
Língua exótica: a libras como um dispositivo de condução
(Universidade Federal de São Carlos, 2023-10-27)
Nascimento, Gabriel Silva Xavier
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Martins, Vanessa Regina de Oliveira
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https://lattes.cnpq.br/4768682330164550
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https://orcid.org/0000-0003-3170-293X
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https://lattes.cnpq.br/4507944299087617
Based on the concept of exoticization as a technique of existence-driving, this thesis analyzes the historical trajectory and discursive practices that shaped linguistic governance in the history of deaf education in Brazil. It is a documentary bibliographical research that relies on compiling a historical archive encompassing the proceedings and supplementary records from international congresses about deaf education between 1878 and 1980. The main objective is to construct the exotic and linguistic exoticization concept to examine how the historical trajectory and discursive practices in the history of deaf education enabled forms of governmentality. The specific objectives are: i) Conceptually structure exoticization as a lens for analyzing discursive practices; ii) Delimit the idea of a historical archive as a multifaceted set of organized sources for weaving history; iii) Engage in reflections on how perspectives on sign languages allow for the emergence of alternative ways of being deaf. The archive's bibliographical materials allow for an exploration of the Brazilian colonial period to the machinery of linguistic governance of the Modern State, with its reverberations on the sociopolitical aspects of deaf people and Brazilian Sign Language - Libras. The reflections are woven within the scope of authors in Foucauldian Studies, Deaf Studies, and Historical Sociolinguistics, employing the concepts of governmentality and counterconduct as analytical tools. The notion of the exotic is conceived as an invention strengthened by colonial invasions to characterize groups diverging from the white-European sociocultural standard. Thus, the practice of a understanding marked by exoticization takes on three historical facets: colonial exotic – focusing on the domination and exploitation of labor; docile exotic – focusing on the capture and docility of bodies subjected to State machinery and; counter-conduct exotic – focusing on the protagonism and subversion of governance techniques for historical reclamation and self-management for a deaf way of being in and through sign language. The thesis contributes to a modern understanding of Libras as an exotic language, i.e., a philosophical perception denoting an existence marked by governmental strategies that not only subject but also produce resistance and counterconduct among Brazilian deaf individuals, enabling the maintenance of deaf life within difference, operating within inclusive rationality. Keywords: Special Education; Deaf Education; History; Exoticization.