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Análise de meios filtrantes em filtros de mangas do processo de dessulfuração da siderurgia
(Universidade Federal de São Carlos, 2024-07-18)
Vieira, Ana Cristina Coelho
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Sartim, Rafael
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https://lattes.cnpq.br/0380809249444032
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Aguiar, Mônica Lopes
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https://lattes.cnpq.br/0431688649128529
The emissions of ultrafine particles in the air are considered a global problem. The increase is linked to economic development and extensive urban expansion. These particles are inhalable, and exposure to them can cause various diseases or even lead to death. As a result, there has been a need to develop and optimize methods and equipment to control their emissions. In this context, bag filters stand out as one of the most commonly used filters due to their high filtration efficiency and stability. However, the filter medium used directly affects filtration efficiency, and how the filter medium is manufactured—such as needle felt and hydroentangled felt—also impacts efficiency and lifespan. Given the existing gap in the literature regarding the influence of filter medium manufacturing techniques on filtration efficiency and their impact in industrial settings, the objective of this research is to analyze and compare the filtration performance of filter media manufactured using needle felt and hydroentangled felt techniques, both virgin and with 3- and 4-year usage, in the bag filter system of the desulfurization process in the steel industry. The particulate material and filter media used were characterized to understand their behavior during filtration tests. Filtration tests were conducted using a test filter based on the VDI 3926 standard, with pulse-jet cleaning, evaluating collection efficiency and pressure drop evolution over 30 filtration cycles. The results of particulate material characterization showed that it is predominantly composed of calcium and iron, with a median aerodynamic diameter of 2.64 µm. The hydroentangled filter medium, along with a larger fiber diameter, exhibited lower thickness and permeability compared to the needle felt. Consequently, the penetration of particulate material into the hydroentangled medium was lower, facilitating the cleaning process of the filter bags and increasing filtration efficiency. After 30 filtration cycles, the used hydroentangled filter medium achieved an efficiency of approximately 99.9%, while the needle-felt filter medium reached approximately 99.7%. Regarding lifespan over the years, the 4-year-old filter bags showed greater residual pressure drop than the 3-year-old bags, as expected due to particle accumulation in the filter medium over time. However, the increase in residual pressure drop was smaller for the hydroentangled bags than for the needle-felt bags, resulting in a longer lifespan. Therefore, under the analyzed conditions, the hydroentangled filter medium demonstrated greater effectiveness, with a longer lifespan and lower residual pressure drop during filtration.
Bounds on the critical parameter for the frog model on trees
(Universidade Federal de São Carlos, 2024-07-18)
Pena, Caio Augusto de Carvalho
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Gallo, Alexsandro Giacomo Grimbert
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https://lattes.cnpq.br/4037274656833325
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https://lattes.cnpq.br/8701983533033982
We consider the frog model with a lifetime on infinite trees. In this model, frogs (particles), when awake, perform a symmetric random walk on the tree, waking up all dormant frogs at the sites visited until they die. We consider variations of the model by changing the structure of the tree (oriented or not, random or not) and the survival distribution. In these models, the survival probability of a frog is controlled by a parameter $ p \in [0,1] $, and there is a critical value $ p_c $ such that if $ p < p_c $, then only finitely many frogs are awakened with probability 1, while if $ p > p_c $, infinitely many frogs are awakened with positive probability. The thesis is dedicated to obtaining lower and/or upper bounds for this critical parameter as a function of structural constants of the considered models.
Soldagem de tubos centrifugados brutos de fundição e carburizados da liga 35Cr45NiNb: microestrutura e propriedades mecânica em tração e fluência
(Universidade Federal de São Carlos, 2024-07-18)
Corsi, Waleska Laisa
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Zepon, Guilherme
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https://lattes.cnpq.br/7924187202036614
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Koga, Guilherme Yuuki
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https://lattes.cnpq.br/0933095081175012
The 35Cr45NiNb alloy is widely used in hydrocarbon cracking furnaces due to its excellent resistance to oxidation and creep. However, this material is susceptible to carburization, which causes deterioration of mechanical properties and makes it necessary to replace the carburized sections. The remaining tubes in the equipment are eventually in an aged and/or carburized condition, therefore, they have low weldability, making it difficult to join new tubes, and compromising the mechanical performance of the weld. The objective of this work was to evaluate the effects of the welding process on the mechanical properties in tensile and creep of as cast and carburized 35Cr45NiNb tubes. The joining of the as cast segments (B) and tubes with approximately six years of use (C) was carried out using the Gas Tungsten Arc Welding (GTAW) technique, resulting in the joints B-B, B-C and C-C. The micrographs of the weld joint obtained by scanning electron microscopy (SEM) showed the growth of precipitates in the heat affected zones (HAZs), mainly in those located between segments C and the weld metal (WM), which acquired sizes relatively larger than those of the base metal (BM). These microstructural heterogeneities, combined with those pre-existing in the BM due to aging and carburization, caused a gradual reduction in the tensile strength and elongation at room temperature, as well as a decrease in the creep failure time (CFT) at 1100 ºC and 16 MPa.
Redução de CO2 a partir de reações de catálise homogênea com complexos bimetálicos de cobalto
(Universidade Federal de São Carlos, 2024-07-18)
Santos, Mayara Fontanelli dos
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Marques Netto, Caterina Gruenwaldt Cunha
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https://lattes.cnpq.br/8042236152815373
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https://orcid.org/0000-0002-3285-4129
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https://lattes.cnpq.br/9422151542979888
This work addresses a topic of significant contemporary relevance: the growing concern about pollution caused by greenhouse gases, which exacerbate global warming and consequently result in extreme weather events in various regions worldwide. This study presents important data on homogeneous catalysis reactions and CO2 electroreduction, aiming to produce formaldehyde and methanol—compounds that are highly useful in the industry—using a bimetallic cobalt (II) complex as a catalyst. The research delves into the analysis of metallic complexes, providing detailed information on the coordination between the metal and the ligands, and justifying the choice of cobalt as the catalytic metal. In the context of CO2 reduction, different types of catalysis are explored, including photocatalysis and electrocatalysis, as well as the three main forms of CO2 capture: pre-combustion, post combustion, and direct air capture. By comparing with complexes reported in the literature, it is concluded that the CO2 reduction process using a bimetallic cobalt (II) complex is feasible. The presence of two metals in the complex offers significant advantages, enhancing the selectivity and efficiency of the catalytic process and the presence of the ligand can affect the stability.
Minimalidade de coincidências do tipo Borsuk-Ulam em superfícies utilizando tranças
(Universidade Federal de São Carlos, 2024-07-18)
Silva, Caio Lima
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Laass, Vinicius Casteluber
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https://lattes.cnpq.br/8470339884809920
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https://orcid.org/0000-0002-8796-9599
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Vendrúscolo, Daniel
Given topological spaces $M$ and $N$, with $M$ equipped with a free involution $\tau$, we define the set of Borsuk-Ulam coincidences as $$ \operatorname{BUCoin}(f; \tau) = \{ \{ x, \tau(x) \} \ | \ f(x) = f(\tau(x)) \}. $$ In this work, we want to exhibit $g \colon M \to N$ homotopic to $f$ such that it minimizes the cardinality of set of Borsuk-Ulam coincidences. In the cases where spaces are surfaces, we will show an algebraic technique involving braid groups of surface that is useful to study such a problem. This technique also displays the index of each Borsuk-Ulam coincidence, seen as coincidences classes. We will give an explicit answer to the problem when both spaces are Klein bottles. Note: Due to special Character restrictions, please check the abstract in the full text available for download.
Catalisadores NiMoS suportados em sílicas mesoporosas ordenadas para a hidrodessulfurização de organossulfurados refratários: efeito do ácido oxálico como agente quelante e avaliação de fases ativas
(Universidade Federal de São Carlos, 2024-07-19)
Albuquerque, Jonas Santana
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Urquieta-González, Ernesto Antonio
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https://lattes.cnpq.br/2389975677904655
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https://orcid.org/0000-0001-5141-6004
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https://lattes.cnpq.br/9732884471657315
In the last decades, regulatory agencies have been establishing stricter specifications for fuels in relation to the emission of pollutants and, especially, the sulfur content. Therefore, hydrodesulfurization (HDS) is an essential step in oil refining for the production of fuels with a low content of organosulfur compounds, respecting the specifications proposed by current legislation. Conventional catalysts are based on metal sulphides of NiMo supported on alumina, however, due to its low hydrogenating capacity and strong metal-support interaction, HDS of refractory organosulfur becomes limited. Seeking to minimize these limitations, the objective of this work was the study of catalysts, supported on mesostructured silicas, with subsequent evaluation in the HDS reaction of dibenzothiophene and 4,6-dimethyldibenzothiophene. Different methodologies for the synthesis of mesostructured supports (SBA-15, SBA-16 and Al-SBA-15) and the influence of using oxalic acid as a chelating agent on the impregnation of the nickel precursor were evaluated in this sudy. Results show that mesostructured supports with optimized textural properties and moderate Brønsted acidity play an important role in obtaining highly active catalysts for HDS of refractory compounds. The use of oxalic acid generated nickel oxalate complexes with low interaction with molybdenum, increasing the dispersion and formation of the MoS2 active phase, especially in catalysts supported on Al-SBA-15. All oxide precursors with oxalic acid, (Ni-AO)Mo, showed reduction peaks at lower temperatures and hexacoordinated molybdate species with octahedral geometry (Mo (Oh)). The NiMoS/Al-15 and (Ni-AO)MoS/Al-15 catalysts presented the highest DBT conversions, while the NiMoS/15 catalyst was considered the most promising for the HDS of 4,6-DMDBT, as it presented the highest hydrogenating capacity, better dispersion of the active phase and total conversion of the organosulfur compound into desulfurized hydrocarbons. Finally, the (Ni-AO)MoS/Al-15 catalyst achieved conversions above 90% at the end of the 8 h reaction of the third reuse cycle, showing that no apparent deactivation occurs.
Análises térmicas em sistemas poliméricos: uma ferramenta para a avaliação da degradação
(Universidade Federal de São Carlos, 2024-07-19)
Lopes, Jameson Santos
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Cruz, Sandra Andrea
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https://lattes.cnpq.br/9632409046763256
In the contemporary world, the demand for polymeric materials has grown intensely to meet the pace of consumption. In view of this, concern about the disposal of polymers becomes an issue when considering waste management. Thus, investigating the impact of degradation on the physical and chemical properties of these materials by means of thermal analyses is a possible approach to this problem. To accomplish this, this study was structured to introduce basic concepts on the subject as well as address the degradation mechanisms undergone by polymers and their precursor agents, refer to the impacts of degradation on the properties of some polymeric systems, and discuss the fundamentals, characteristics, and parameters of thermal analyses. Thermal analyses are a group of various techniques that measure the physical and chemical properties of a given material as a function of temperature under controlled atmospheric, heating and cooling conditions. The properties of the sample are analyzed by monitoring the changes in the material as a function of time and temperature compared to a reference, which makes it possible to determine certain physical and chemical properties of the material in order to determine its possible applications, storage, behavior, and transport. For this work, the focus will be on Differential Scanning Calorimetry (DSC) analyses, which monitor the flow of heat through the sample over time and temperature. With DSC it is possible to determine the Vitreous Transition Temperature (Tg), Crystaline Melting Temperature (Tm) and Crystallization Temperature (Tc), the melting enthalpy (∆Hf), degree of crystallinity (Xc), specific heat, phase transition, curing and crystallization kinetics. And Thermogravimetric Analysis (TGA), which relates the change in mass in a sample under a controlled atmosphere; it investigates the thermal decomposition profile of the material. With TGA, we can study the thermal stability of the sample, thermal decomposition, moisture content and pyrolysis of certain substances. This work will conclude with a discussion of two case studies. The first one will address the use of thermal analyses to understand the effects of degradation on Nylon 6,6, while the second will investigate the durability of cables in nuclear plants.
Agroecologia e construção do conhecimento: um estudo de caso da práxis da Comunidade que Sustenta a Agricultura (CSA) Sorocaba
(Universidade Federal de São Carlos, 2024-07-19)
Souza, Thais Santos de
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Franco, Fernando Silveira
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Lattes: http://lattes.cnpq.br/3218633711361955
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Duval, Henrique Carmona
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https://lattes.cnpq.br/1127516712972199
Agroecology is built on the valorization of knowledge, respectful relationships between all beings, solidarity economy and the focus on conservation and management of biodiverse agroecosystems. Aligned with Agroecology, the global organization Community that Sustains Agriculture (CSA) emerged in the 1960s, which seeks actions of solidarity, collaboration and affection, through the fair marketing of quality food. In recent years, CSA have grown in several Brazilian municipalities, associated with principles that dialogue with agroecology. The central objective of the work is to study the communication strategies and construction of agroecological knowledge that occur through the Community that Sustains Agriculture (CSA) based on the case study of CSA Sorocaba, located in the state of São Paulo. The approach used is action research, using active methodologies, semi-structured interviews and focus groups. As a result, the aim is to systematize the experience, outlining strategies that allow the future exploration of the power of agroecology in the reconstruction of a critical, humane, transformative science aligned with popular principles.
Percepção de serviços ecossistêmicos por alunos do ensino médio e superior
(Universidade Federal de São Carlos, 2024-07-22)
Almeida, Paula Carolina Setti de
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Francisco, Bruno dos Santos
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https://lattes.cnpq.br/0670209258231584
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Piña-Rodrigues, Fátima Conceição Márquez
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https://lattes.cnpq.br/1475369713141675
The study on environmental education themes is a path that allows the construction of scientific knowledge regarding socio-environmental issues. Ecosystem services are the benefits that natural ecosystems provide to humans. Understanding and valuing ecosystem services through environmental education is essential for the conservation and sustainable use of natural resources. This work investigated and compared the understanding and perception of students, both from high school and from undergraduate Biological Sciences, regarding ecosystem services through a semi-structured questionnaire applied in a state school in Sorocaba and on the campus of a public university in the city of Sorocaba. The research demonstrated that there were differences in the perception of ES among students at different educational levels, with significant differences in perception evidenced by statistical tests, in the IPSE (Index of Perception of Ecosystem Services), and in the calculation of percentages. The lack of uniformity in understanding environmental services can be attributed to exposure to information through formal education, as well as social and cultural experiences shared among participants. The study highlights the need for specific educational strategies to promote awareness and understanding of ecosystem services, especially among high school students, whose perception may be limited by a lack of educational interventions tailored to their needs. The results emphasize the importance of environmental education in enabling individuals to understand and value ecosystem services, contributing to the construction of more sustainable and environmentally conscious societies. It is recommended to include topics related to biodiversity and ecosystem services early in the high school curriculum, accompanied by practical and theoretical activities to stimulate interest and understanding of these concepts as early as possible. Thus, raising the level of environmental awareness, which becomes broader with the introduction of scientific concepts of ecosystem services, contributes to a comprehensive understanding of the social and environmental impacts of known spaces, allowing for the proper importance to be given to the ecosystem and quality of life.
Evaluation of the chemical composition and surface acidity of mesoporous acidic catalysts in the production of 5-hydroxymethylfurfural and furfural from monosaccharides
(Universidade Federal de São Carlos, 2024-07-22)
Vieira, José Lucas
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Gallo, Jean Marcel Ribeiro
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https://lattes.cnpq.br/3485408327490746
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https://orcid.org/0000-0003-2937-2628
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Oliveira, Cauê Ribeiro de
This thesis investigates the synthesis, composition, and surface acidity of various mesoporous acidic catalysts and their impacts on the catalytic dehydration of monosaccharides into the platform molecules 5-hydroxymethylfurfural (HMF) and furfural. Niobium phosphates with different P/Nb molar ratios were prepared, affecting their Lewis/Brønsted acid site (L/B) ratio and catalytic activity. Catalysts with high P/Nb ratios exhibited low L/B ratios, whereas catalysts with low P/Nb ratios, high L/B ratios. Additionally, a linear correlation between the L/B ratio and reaction rates for HMF and furfural production from glucose and xylose, respectively, was demonstrated. Based on that, we synthesize a controlled mesoporous bifunctional carbon catalyst to more easily produce a catalyst with L/B ratios for platform molecules production. First, we prepared sulfonated carbons with only Brønsted acidity for the dehydration of fructose and xylose into HMF and furfural, respectively. They had different concentrations of stronger (sulfonic acid groups) and weaker acid sites (carboxylic acid, alcohol, phenol groups). The ratio between stronger and weaker acid sites (NS/NW) was found to significantly influence catalytic performance, with optimal yields and turnover numbers observed at NS/NW ratios of 2 – 4, suggesting a synergistic role of both types of acid sites in the catalytic mechanism. Finally, two promising sulfonated carbons from the previous study were selected and underwent partial ion-exchange with metallic cations with Lewis acidity (Al3+, Sc3+, Fe3+, Cu2+, Sn4+, Yb3+) to produce ion-exchanged bifunctional carbons with different L/B ratios for dehydrating glucose and xylose into HMF and furfural, respectively. Even though no characterization regarding surface acidity has been performed yet, the strength of the Lewis acid sites likely plays a crucial role in the monosaccharide conversion, with stronger sites (Al3+, Cu2+, and Yb3+) leading to isomers; intermediate strength sites (Sc3+) leading to both isomers and platform molecules, and weaker sites (Sn4+) leading to platform molecules. The catalyst with 20 % of Brønsted acid sites exchanged with Sn4+ (20%-Sn(IV)-Amb-45) showed promising results, achieving 41 % HMF selectivity at 57 % glucose conversion and 47 % furfural selectivity at 65 % xylose conversion, whereas 100%-Al(III)-Amb-45, 100%-Cu(II)-Amb-45, and 100%-Yb(III)-Amb-45 were promising for isomerization reactions.
Redes de cuidado e a assistência ofertada às crianças e adolescentes com transtorno do espectro autista em um município de médio porte
(Universidade Federal de São Carlos, 2024-07-22)
Bolatto, Nicole Bizarro
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Fernandes, Amanda Dourado Souza Akahosi
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https://lattes.cnpq.br/7901666626822625
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https://lattes.cnpq.br/2076915386823594
Autism has been a present and prominent topic in the current context, especially in terms of concerns the care offered in the intra and intersectoral network, considering that the construction of public policies for this segment were implemented late. Given this, the objective of present study was to understand how assistance is given to children and adolescents with autism spectrum disorder in the intra and intersectoral care network of a city in medium size in the interior of the State of SP, from the perspective of those responsible or caregivers main. Five people responsible for autistic children and teenagers participated. The collection of data occurred in person and online, based on the choice of participants, being in On this occasion, a semi-structured interview guide was applied. The data was analyzed based on of content analysis. The results indicated that existing equipment is not sufficient for demand, so that family members wait for a long period of time to access diagnosis or treatment. However, they state about powers that touch on the bond established with professionals, the availability of even in welcoming and listening. It is also noteworthy that family members regularly access and have good links with basic health units and, in relation to schools, the The inclusion process involves barriers and challenges. Other network equipment as well have been activated by participants to guarantee rights, such as guardianship council and the specialized social assistance reference center. It is expected that the results obtained can contribute to further reflections on this topic, as well as to the qualification of the care offered
Atividade física no trabalho, lazer e sono em profissionais da saúde em ambiente hospitalar
(Universidade Federal de São Carlos, 2024-07-23)
Cardoso, Beatriz Medeiros
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Triches, Maria Isabel
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https://lattes.cnpq.br/9585150764624635
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https://orcid.org/0000-0002-7606-8218
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Sato, Tatiana de Oliveira
Introduction: Healthcare professionals have had their work hours intensified with the arrival of the COVID-19 pandemic. It is important to investigate, through objective measures, occupational physical activity (OPA) and leisure-time physical activity (LTPA), as well as sleep characteristics. Objective: To describe and correlate physical activity at work and during leisure time with sleep quality and duration and musculoskeletal symptoms in healthcare professionals working in a hospital environment, in the context of the COVID-19 pandemic. Methods: Cross-sectional study with 17 healthcare professionals from hospitals in the city of São Carlos (SP). Data collection was performed using an electronic form, containing a sociodemographic questionnaire, the Nordic Musculoskeletal Symptoms Questionnaire (QNSO) and the Pittsburgh Sleep Quality Index (PSQI-Br). In addition, triaxial accelerometers (Axivity AX3) were used to monitor physical activity. The information was analyzed descriptively and through point-biserial correlation analysis. Results: Most participants had low back pain and poor sleep quality. The predominant postures at work and during leisure time were, respectively, sitting (50% and 41%) and standing (30% and 24%). The number of steps was higher during work. There was a negative correlation between light physical activity on non-work days and symptoms in the lumbar spine (r=0.69), feet (r=0.58) and shoulder (r=0.62); and between moderate to vigorous physical activity during leisure time and knee pain (r=-0.68). Conclusion: The practice of physical activity outside the work environment was associated with musculoskeletal symptoms in health professionals. Promoting the practice of physical activity can help in the prevention and control of musculoskeletal symptoms, especially in periods such as the COVID-19 pandemic.
Crianças autistas com e sem ecoico generalizado: um estudo exploratório sobre o ensino do comportamento de ouvinte
(Universidade Federal de São Carlos, 2024-07-23)
Talarico, Mariana Valente Teixeira da Silva
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Goyos, Antônio Celso de Noronha
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https://lattes.cnpq.br/3407008711535651
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https://orcid.org/0000-0002-6150-1074
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https://lattes.cnpq.br/9804047279859169
Several studies have been developed to install, increase and improve verbal behavior, especially in people with Autism Spectrum Disorder. Recent research suggests that in some cases, the acquisition of a verbal operant can give rise to others, without specific training. This focus on emergent verbal behaviors advocates that a response acquired under the control of the conditions of one verbal operant is transferred to the conditions of another, without direct instruction. The objective of the present study was to analyze the effects of listener training on the tact repertoire of autistic children with and without generalized echoic. Nine children participated in the study and were divided into two groups: group 1 - participants who presented a generalized echoic repertoire (P1, P2, P3, P4) and group 2 - participants who did not present a generalized echoic repertoire (P5, P6, P7, P8, P9). The procedures followed the following steps: 1- assessment of sitting behavior; 2- assessment of visual contact under instructional control; 3- behavioral assessment of initial repertoire; 4- assessment of generalized echoic; 5- listener and speaker baseline; 6-generalized echoic and motor imitation probe; 7- listener training; 8- speaker test (P1, P2, P3, P4, P5); 9- additional training (P6, P7, P8); 10- simple simultaneous discrimination (P6); 11- generalized echoic and motor imitation probe (P6, P7, P8, P9); 12- behavioral reassessment. As it is an exploratory study, it must be considered inconclusive, however it allows the establishment of important correlations between the data collected. All participants who presented the generalized echoic repertoire at baseline learned the auditory-visual (listener) discrimination of abstract stimuli Omega and Pi, with a relatively reduced number of teaching sessions (between four and fourteen sessions), and presented the rapidly emerging naming/tact relations (between three and eight sessions). On the other hand, participants who did not present a generalized echoic repertoire at baseline were unable to learn the listener and speaker repertoires of the same stimuli, although significant numbers of teaching sessions were carried out, as well as the insertion of alternative teaching and/or adjustments to teaching procedures. These results, in general, corroborate the proposal of Goyos (2018), who considers the generalized echoic repertoire as a prerequisite for more complex verbal/vocal skills and for socialization.
Respirar como direito de existir: epistemologia do armário e trajetórias de vida de mulheres lésbicas
(Universidade Federal de São Carlos, 2024-07-23)
Moraes, Simone Silveira
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Mendonça, Viviane Melo de
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https://lattes.cnpq.br/4827331651090223
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https://orcid.org/0000-0002-1368-1883
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https://lattes.cnpq.br/8511812158414809
The research aimed to analyze the life trajectories of lesbian women, focusing on the experiences of refuges and coming out of the closet in the context of their relationships with other women in the family and how these interactions can affect mental health, especially with regard to anxiety. Using a qualitative approach and semi-structured interviews, three women who self-identify as lesbians, living in the interior of the State of São Paulo, aged between 35 and 48, were interviewed. The speeches of these women were analyzed based on the theoretical-methodological discursive practices of social psychology. The results revealed that lesbian women face high levels of anxiety due to the heteronormative prejudice still prevalent in society. Another aspect identified was that the impact of social class and race on the experiences of these women, found in the analysis of the intersectionality of sexual orientation, class and race, further aggravates the prejudice and discrimination experienced. Black lesbian women face the accumulation of the color marker in their struggles and financial vulnerability affects lesbian women even more, especially in the face of family discrimination, when it can force them to leave home. Thus, the analysis of the interviews identified that interactions with family members, especially with women in the family, can be both sources of support and stress, significantly influencing the mental health of the interviewees, revealing that family acceptance or rejection affects anxiety levels of lesbian women. The research also revealed the role of religion in the lives of the interviewees and how religious backgrounds can contribute to increased levels of anxiety, as well as establishing themselves as a source of well-being and belonging. The study revealed that lesbian women can face great difficulty breathing when they come out of the closet, as the looks of family members who could welcome them often fail to recognize their identity.
Aceitação do uso de robôs de serviço no cuidado e apoio às pessoas idosas
(Universidade Federal de São Carlos, 2024-07-23)
Cesário, Larissa Cayla
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Mendes, Glauco Henrique de Sousa
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https://lattes.cnpq.br/7564259060572565
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https://orcid.org/0000-0001-8086-3321
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https://lattes.cnpq.br/4633633758571142
Social service robots constitute an alternative solution for the care of elderly individuals. Their usage has become popular in several countries, especially those experiencing intensified shortages of healthcare human resources. However, this technology remains underexplored in Brazil. The objective of this study was to identify factors contributing to the acceptance of service robots in the care of elderly individuals in Brazilian households. To achieve this, three research stages were conducted using different methods. The first stage involved a bibliometric review to identify key research themes in literature concerning social service robots and elderly care. The second stage utilized a survey to assess acceptance and intention to use social service robots among a sample of potential users in Brazil, employing the adapted Service Robot Acceptance Model. The third stage comprised semi-structured interviews to delve deeper into issues regarding potential users' detailed impressions of service robot usage. Results revealed the intellectual framework of this literature organized into six clusters: (i) robot acceptance and design, (ii) social role and ethical values, (iii) barriers and criticism, (iv) effects, efficacy, and impact of robot use, (v) therapeutic use of robots, and (vi) perceptions of healthcare professionals and services, alongside a proposed future research agenda. In stage 2, data were analyzed using Structural Equation Modeling techniques, while interview data were subjected to Content Analysis. Findings confirm the Service Robot Acceptance Model within the context of elderly care, demonstrating high predictive capacity. Additionally, the value of social service robots was confirmed, emphasizing significant functional elements for elderly acceptance. Moreover, elderly individuals expressed an intention to use social service robots for emotional comfort. However, they did not perceive robots as real people capable of fully replacing human care, indicating the establishment of a relationship with emotional boundaries. This dissertation contributes to advancing research on the topic and supporting elderly care and support within the Brazilian national context.
Design of Ti-Nb-Cr alloys for hydrogen storage: exploring hydride destabilization through Nb/Ti ratio adjustment
(Universidade Federal de São Carlos, 2024-07-23)
Dias, Gabriela Chimello Mayer
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Zepon, Guilherme
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https://lattes.cnpq.br/7924187202036614
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https://lattes.cnpq.br/7085380229734116
Hydrogen is emerging as a promising alternative to fossil fuels amidst concerns over depleting reserves and environmental impacts. However, efficient hydrogen storage remains a significant challenge for widespread application. Solid-state storage, especially using metal hydrides, presents a promising solution for efficient storage at moderate pressure conditions. Alloys with a body-centered cubic (BCC) structure, such as those in the Ti-V-Cr and Ti-V-Nb-Cr systems, have shown promising properties. Notably, studies specifically on hydrogen storage in Ti-Nb-Cr ternary system alloys are scarce, with results emphasizing high hydride stability. To enhance the efficiency of MH-based hydrogen storage systems, achieving hydrogen desorption at low temperatures is crucial. In this context, this study investigates the hydride destabilization in the Ti-Nb-Cr system by designing alloys with a reduced concentration of the stronger hydride-forming element, Ti, and an increased fraction of the weaker hydride-forming element, Nb. To favor a predominant body-centered cubic (BCC) phase, Cr content was maintained below 35 at.%. The impact of these compositional adjustments on key properties for solid-state hydrogen storage was thoroughly examined. Trends in the plateau pressures of the Pressure-Composition-Temperature (PCT) diagrams were predicted using a thermodynamic model. Four compositions were studied: Ti1.0Nb1.0Cr1.0, Ti0.8Nb1.4Cr1.0, Ti0.6Nb1.8Cr1.0, and Ti0.4Nb2.2Cr1.0. These alloys were synthesized via arc melting and predominantly exhibited a BCC phase with a fraction of C15 Laves phase. All alloys showed rapid absorption kinetics and attained maximum hydrogen storage capacities of 2.79 wt.%, 2.30 wt.%, 2.23 wt.%, and 2.09 wt.%, as the Nb/Ti ratio increased. After 10 cycles, capacities decreased by 0.20 wt.%, 0.16 wt.%, 0.17 wt.%, and 0.26 wt.%, respectively. PCT diagrams indicated that increasing the Nb/Ti ratio resulted in higher plateau pressures, nearly reaching 1 bar in absorption for the Ti0.4Nb2.2Cr1.0 alloy. Thermal analysis revealed that the enthalpy of desorption became lower with increasing the Nb/Ti ratio, indicating hydride destabilization.
Implicações da insônia e do tempo de duração do sono na redução da força neuromuscular e velocidade de caminhada em pessoas idosas: evidências do estudo ELSA
(Universidade Federal de São Carlos, 2024-07-24)
Silveira, Leticia Coelho
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Alexandre, Tiago da Silva
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https://lattes.cnpq.br/5393622641681701
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https://orcid.org/0000-0003-3791-9793
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https://lattes.cnpq.br/7670409228888469
Introduction: The decline in neuromuscular strength (NS) and walking speed (WS) are associated with adverse outcomes in older adults, such as falls, hospitalizations, functional decline, and death. Although multifactorial, the decline in NS and WS appears to be influenced by insomnia symptoms and sleep duration. However, the little longitudinal evidence on the topic is controversial, and exploring this topic in studies with more extended follow-up periods is essential. Objectives: This dissertation has two objectives: 1) Analyze sex differences regarding the influence of sleep duration and insomnia symptoms on the trajectory of NS decline in people aged 50 or over during eight years of follow-up, and 2) Analyze the influence of sleep duration and insomnia symptoms on the trajectory of WS decline in people aged 60 or over during eight years of follow-up. Methods: Data came from the English Longitudinal Study of Aging (ELSA Study). To analyze the trajectory of NS decline, 6,429 participants aged 50 years or older with NS ≥ 27 kg for men and ≥ 16 kg for women were included. To analyze the trajectory of WS decline, 3,208 participants aged 60 years or over with WS > 0.8 m/s were included. In both studies, insomnia symptoms were assessed using the adapted and validated Jenkins questionnaire, and sleep duration was analyzed by self-report and classified as short (≤6 hours), ideal (>6 to <9 hours), and long (≥ 9 hours). Generalized linear mixed models estimated the decline rates of NS stratified by sex and WS in separate models as a function of insomnia symptoms and sleep duration and controlled for sociodemographic, behavioral, clinical, and anthropometric characteristics. Results: Regarding NS, over the eight years of follow-up, the greater number of insomnia symptoms was associated with a higher rate of NS decline in men (– 0.02 kg per year 95% CI – 0.04 – – 0. 01) while long sleep duration (≥ 9 hours) was associated with a higher rate of NS decline in women (– 0.14 kg per year 95%CI – 0.26 – – 0.03). Regarding WS, over the eight years of follow-up, only long sleep duration (≥ 9 hours) was associated with a higher rate of decline in WS (– 0.01 m/s per year 95% CI – 0.02 – – 0.01). Conclusion: Sleep changes influence the rate of NS decline differently between the sexes. In men, increased insomnia symptoms, while in women, long sleep duration (≥ 9 hours) increases the rate of NS decline in people aged 50 and over. As for WS, long sleep duration (≥ 9 hours) increases the risk of WS decline in people aged 60 years or older of both sexes.
Fatores de influência no engajamento e confiança em equipes SCRUM na migração do regime de trabalho presencial para o híbrido em uma empresa do setor aeronáutico
(Universidade Federal de São Carlos, 2024-07-24)
Resende, Cassio Lara
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Delai, Ivete
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https://lattes.cnpq.br/7054145506480670
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https://lattes.cnpq.br/3564549747499974
This study analyzed the factors that influence the engagement and trust of agile teams in the migration from in-person to hybrid work (part remote and part in-person) due to the COVID-19 pandemic, through the analysis of a product engineering department in the aeronautical industry. The COVID-19 pandemic forced the company to put the entire department into remote work and later into a hybrid work regime. This study evaluated whether there was a change in the factors that make up performance in this migration to the hybrid work regime in this company, which uses the agile approach in team management with the SCRUM method as a tool for managing activities. Agile methods were developed to be applied in a face-to-face environment and have as a central characteristic the interaction between team members, with quick and daily meetings, the so-called stand-up meetings. Problems faced by companies that use agile approaches in a remote environment were found in the literature, such as difficulties in using SCRUM ceremonies and decreased team autonomy with increased control over activities, thus influencing performance factors. A questionnaire was developed based on seven factors: autonomy, communication, ceremonies, roles, engagement, trust, and mutual support. The questions used a Likert scale from 1 to 5, and the interviewees responded about two periods, before the pandemic (in-person) and after the pandemic (hybrid), in addition to answering questions about their knowledge of the SCRUM method. After applying the questionnaire to the company studied, the data were compiled and analyzed using partial least squares structural equation modeling (PLS-SEM). Statistical analysis of the data showed that there was no significant change in the relationships between the factor’s engagement, trust and mutual support, that influence the performance of agile teams, thus demonstrating that the model of relationships in remote and hybrid work regimes does not change. Likewise, there was no change in the variables that make up the agile performance factors (engagement, trust and mutual support). Based on the characterization of the members, the problems encountered in the application of the method, such as roles and ceremonies, may be related to the lack of knowledge and training of the teams, especially the SCRUM master. This study brought as a theoretical contribution to the literature, the study of impact on the performance of product engineering in a non-software development company, in a hybrid work regime (part remote and part in-person), compared to in-person work, responding to the academic gap. As a technological product, this study developed a conclusive technical report demonstrating how the factors that influence team performance were not changed in the migration from in-person to hybrid work, as well as the main factors that influence such performance in order to support the company in proposing improvements to the SCRUM method.
Alternância pronominal e concordância nominal e verbal na língua bissau-guineense
(Universidade Federal de São Carlos, 2024-07-25)
Nunes da Fonseca, Janifer
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Araújo Vale, Oto
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https://lattes.cnpq.br/2277403284693571
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Rubio, Cássio Florêncio
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https://lattes.cnpq.br/8357993415342241
Es tarbadju tene suma obidjetivu di diskribi aspectus di alternansia pronominal, di konkordansia nominal di sintagma nominal-sudjetu i di paradigma di konkordânsia verbal na lingu bissau-guineense (ku ta tchomadu tambi di kryol, kryol di Guiné-Bissau, guineense ô crioulo guineense). Na basi di es obidjetivu garandi, tarbadju tene quatru obidjetivus pikinus: ntundi mindjor funson ku strutura di pronomis pessoais na funson di sudjetu na lingu bissau-guineense; analiza di pontu di vista qualitativa/quantitativa e descritiva /exploratória, prosesus di variason ku na relasionadus ku quadru pronominal na lingu bissau-guineense; diskribi strutura ku funson di verbu dentru di okorensias; splica formas di paradigma verbal di diskursu na singular ku plural na lingu bissau-guineense. Studu fundamentadu, na pontu di vista diskritivu, na tarbadju di es piskisadores Perini (2003); Couto e Embaló (2010); Intumbo (2007), Scantamburlo (1999, 2021); Tavares (2021) e Castilho (2010), i ku utrus djintis, i na pontu di vista di metudu di sociolinguística, no tene Labov (2008) e Mollica (2003). Di pontu di vista metodologiku, a abordagem i qualitativa/quantitativa, ku aplikason di formularios ben struturadus, ki buska informasons di aspectus relasionadus ku tematika propostadu na objetivus, i konta ku partipason di 63 estudantis guineenses, ku mora na Brasil i na Guiné-Bissau. Pa kabanta es tarbadju no sai ki es resultadus: i) lingu bissau-guineense tene variason na tudu djintis di discursu, na kil ku ta rifiri forma ku no ta pui pronomis; ii) alternânsias pronominais ta da entri manera ke ta mprega es dus formas clíticas e não-clíticas; iii) i ka tene pusiblidadi di paga es dus forma pronominal, pabia lingu bissau-guineense ka tene marca di koncordansia na verbus suma ki ta akontisi na utrus lingu o varidadis, i asin suma na portuguis padron, i na lingu bissau-guineense es strutura ka ta varia, son SN-sudjetu ku ta marka numeru i djintis; iv) paradigma di kondjugason di verbus na lingu bissau-guineense i ta parsi ku utrus lingu ô variedadis, suma inglis padron i ku variedadi di purtuguis pupular, na kil ku ta fala di auzensia di markas di konkordansia na formas di verbus. Nô conclui cuma: i tene variason na kil cu ta rifiri pronomis-sujeitus i ka tene tan marcas di konkordansia verbal suma ki ta akontisi na lingu purtuguis, distakandu variason na uzu di pronomis i auzensia di marcas di konkordansia verbal, aspectus ki ta evidensia influensia di prinsipiu di economia linguistica na strutura des lingu. Analizi conta cuma, plural ta marcadu di forma ki ka redundanti, i ta limita nucliu di sintagma nominal, i ta parsi cu di inglis. I ka tene tan norma-padron i ka tene tan artigu.
Modulation of semiconductors with transition metals: morphological, optical, and electronic properties
(Universidade Federal de São Carlos, 2024-07-25)
Patrocinio, Katiana Lima do
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Silva, Elson Longo da
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https://lattes.cnpq.br/9848311210578810
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https://lattes.cnpq.br/6895713868339732
Research on semiconductors has been of great interest due to their numerous applications. These materials are versatile, and doping, which introduces impurities into the crystal structure, is a common strategy that can enhance their properties. This process directly influences the electronic, optical, and morphological properties, allowing for adjustments to optimize the effectiveness of semiconductors in specific applications.This process directly influences the electronic, optical, and morphological properties of semiconductors, enabling adjustments to optimize their effectiveness for specific applications. Within this context, this study introduces two matrices: silver tungstate (α-Ag2WO4 or AW) and zinc germanate (Zn2GeO4 or ZGO), each dedicated to investigating the influence of doping with transition metals. For AW doped with vanadium at different concentrations (x = 0.0; 0.01; 0.02; and 0.04 mol%), it was demonstrated as a highly efficient catalyst for the oxidation of sulfides to sulfones under mild conditions, exhibiting high yields and selectivity. Sequestration experiments identified the direct involvement of electron-hole (e-/h+) pairs, hydroxyl radical (⦁OH), and singlet oxygen (1O2) in the oxidation process. Electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) analyses confirmed the presence of V4+ cations in the doped samples. Theoretical results suggested that the enhanced catalytic activity of vanadium-doped samples is associated with the predominant presence of the (100) surface morphology, indicating potential applications in sulfide oxidation reactions in the absence of light. For ZGO doped with nickel at different concentrations (x = 0, 0.01, and 0.16 mol%), doping was utilized to tailor its structural and electronic properties towards creating efficient blue pigments for ceramics. Density functional theory (DFT) calculations revealed that the 3d orbitals of Ni2+ generate new energy levels, altering the local electronic structure and resulting in electron transfer that produces the blue color. Analyses confirmed that this modification is responsible for the blue hue, while also highlighting the low toxicity and excellent chemical and thermal durability of the pigments. This work establishes a robust foundation for the design of adjustable and high-performance ceramic pigments. Ultimately, these materials demonstrate the potential of scientific research to drive significant innovations and improvements in real-world technologies and products.