Browsing by Issue Date, starting with "2023-08-28"

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Sustentabilidade de forma prática para a engenharia química: metodologias para a gestão de carbono em atividades produtivas e econômicas
(Universidade Federal de São Carlos, 2023-08-28)
Zanuzzo, Juliana Tavares
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Ferreira Palhares, Adriana Paula
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https://lattes.cnpq.br/5736423072715628
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https://orcid.org/0000-0002-1783-1973
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https://lattes.cnpq.br/9467945485125791
The exponential increase in the concentration of Greenhouse Gases (GHG) in the atmosphere in quantities above the planet's natural capacity is generating the phenomenon of climate change, whose economic, social and environmental impacts have been a source of attention for the international scientific community and global political concern. It is a new scenario that encompasses challenges for the management of productive and economic activities, with new risks and opportunities for innovation for companies. Given this, the market urgently needs professionals trained in this topic, with extensive knowledge of operations and the value chain to manage GHG emissions, in accordance with sustainability protocols and indices. These expectations are aligned with the new National Curricular Guidelines (DCN), which determine that graduates of engineering courses have profiles and competencies that consider global, political, economic, social, environmental, cultural, safety and health aspects at work, and who act with impartiality and commitment to social responsibility and sustainable development. In this context, this work proposes to carry out a bibliographical research on climate change and methodologies for the management of productive and economic activities, considering their sustainability, demonstrating the application of the GHG Protocol method in solving a case study for the development of a teaching and learning strategy. As a result of the research, it was observed that the GHG Protocol method is the most used by companies, and based on the available data, it would be the most coherent for calculating the model case study. With the results of the model case study of 330.23 tons of equivalent emitted in 1 year, it was possible to analyze action plans applied for each emission scope. Furthermore, proposals were presented for applying the content covered in the current work in mandatory and optional subjects, new subjects, extension groups and ACIEPEs (Curricular Activity of Integration of Teaching, Research and Extension), training chemical engineers to meet the new needs of the market. of work.
Percepções de professoras de creche sobre formação, saberes e reconhecimento profissional
(Universidade Federal de São Carlos, 2023-08-28)
Nonato, Giovana Regina
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Onofre, Márcia Regina
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https://lattes.cnpq.br/7176529351192598
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https://lattes.cnpq.br/4401698866169387
This qualitative research aimed to understand, through the perceptions of preschool eachers, the processes related to training, knowledge, and professional recognition.Starting from the following research question: What are the perceptions of preschoolteachers regarding their formative processes, teaching knowledge, and professionalrecognition? In this sense, a survey of research in the area on the topic was conductedinitially, followed by the application of questionnaires and interviews with 10 earlychildhood education teachers working with children aged 0 to 3 years old, at a CEMEIin the municipality of São Carlos-SP. As a backdrop for the analysis, authors from thetheoretical perspective of the epistemology of practice (Alarcão (1996); Freire (1996);Gauthier (2006); Goodson (2015); Nóvoa (1995); Pimenta (2000); Tardif (2012)); andfrom the field of early childhood education were used: Arce (2001); Assis (2007);Oliveira (2014); Onofre, Tomazzetti, and Martins (2017), among others. We believethat the results of the study contributed to strengthening the professionalizationmovement of teachers working at this level of education and to the importance of theprotagonism of their knowledge. The relevance of this study was also justified inpersonal relevance, contributing directly to teaching practice and the school unit of theresearch proponent; in political-pedagogical relevance, considering the possibility oflistening to teachers, pointing out the need for an effective policy of valorization andrecognition of these professionals; in academic relevance, for the perspective ofstrengthening the movement of teacher professionalization. The study showed thatinitial training courses were not sufficient for work in the field, as they did not addressthe specificities of early childhood education; it pointed out that the participants in theresearch are not socially and professionally valued; it reinforced the lack of theirparticipation in political decisions and, finally, it noted the absence of speech andlistening from various instances, promoting silence and the proletarianization of thecategory.
Bolhas finas geradas por novo sistema de vazão pulsada de gás e o seu papel em processos de transferência de massa
(Universidade Federal de São Carlos, 2023-08-28)
Pereira, Rauber Daniel
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Cruz, Antonio José Gonçalves da
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https://lattes.cnpq.br/1812806190521028
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https://orcid.org/0000-0001-6830-9512
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Badino Júnior, Alberto Colli
The use of small-sized bubbles, known as fine bubbles or microbubbles, in mass transfer operations has been extensively discussed, and various bubble generation methods have been developed and applied. However, methods involving the generation of small-sized bubbles at pilot or industrial scale remain unexplored, as well as the role these bubbles play in mass transfer operations. This study aimed to develop a new system for generating fine bubbles, referred to as the Fine Bubble Generator (FBG), within a bubble column reactor. This system comprises a high-frequency (>70 Hz) solenoid valve for generating pulsed gas flow and machined spargers with conventional perforations, i.e., perforations that can be commercially produced (orifices diameters above 0.3 mm). The system was developed and characterized in a pilot-scale bubble column reactor (173 L) by determining the bubble diameters generated under different operational conditions of gas flow, operational frequency, and liquid medium composition. An optimal operating region was observed in the range of 100 to 150 Hz in non-coalescent media, where reductions in bubble diameter of around 33% compared to conventional aeration were achieved. Subsequently, the system was applied to a 10.0 L bubble column reactor to evaluate the volumetric oxygen transfer coefficient (kLa) in coalescent and non-coalescent liquid media. In those operations, spargers with conventional perforations (R8H) and sintered-type spargers (SSD), which naturally generate microbubbles (db < 1000 μm), were used. The pulsed flow system combined with the R8H sparger led to increases in kLa values of approximately 50% and 80% compared to conventional aeration (continuous flow), for non-coalescent and coalescent media, respectively. However, for the SSD sparger, no significant change in kLa was observed, supporting the hypothesis of a minimum natural frequency of bubble formation that needs to be surpassed for premature detachment to occur. Furthermore, the FBG system was employed in ethanol stripping operations within 10.0 L bubble column reactors (using both R8H and SSD spargers) and a 50.0 L bubble column reactor (using a PS3 sparger - conventional perforations of 0.3 mm, scaled in number of orifices for a 50.0 L volume). At this stage of the study, bubble saturation was confirmed under various operational conditions of gas flow rate and bubble diameter. A mathematical model was developed to quantify the fraction of ethanol removed through thermodynamic-driven entrainment (or vaporization) and mechanical entrainment. The latter was found to enrich the gas phase with ethanol concentrations surpassing those achieved through thermodynamic equilibrium selectivity, reaching up to 15 times the liquid phase concentration. This demonstrates the complexity of mechanical entrainment, which depends on bubble diameter, in operations involving the removal of volatile solvents. It also illustrates that, under the right operational conditions, this phenomenon can enhance the efficiency of the stripping process. The final phase of the study involved applying the FBG system to extractive alcoholic fermentation in 10.0 L and 50.0 L bubble column reactors, achieving a productivity increase of around 15% compared to conventional batch fermentation using a specific CO2 flow rate of 0.4 vvm.
Mulheres negras viajantes: protagonistas de suas próprias histórias contadas através de plataformas digitais
(Universidade Federal de São Carlos, 2023-08-28)
Genésio, Denise Aparecida
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Silva, Vanda Aparecida da
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https://lattes.cnpq.br/9920701759600807
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https://orcid.org/0000-0002-7558-6443
This research focuses on analyzing the motivations that drove black women to travel, as well as assimilating the sharing of these experiences in their social networks and online communication channels. The methodology used to collect data consisted of interviews conducted digitally, allowing a qualitative approach to the analysis of the information obtained. Three black women travelers were interviewed, and their responses were compared to identify patterns and trends related to their motivations to travel. Through this research, we seek to better understand the reasons behind the trips undertaken by black women and the meaning that these experiences have in their lives. In addition, it will examine how they share these experiences in their social networks and online channels, contributing to the promotion of diversity in tourism and inspiring other black women to explore the world. The study intends to provide valuable insights into the participation of black women in tourism, revealing their personal motivations and experiences. It is expected that the results obtained may contribute to the enrichment of knowledge about tourism and encourage greater inclusion and representation in the sector, as well as opening new perspectives for future research on the subject. Therefore, it is essential that future investigations take into account this plurality of motivations and experiences, improving knowledge about tourism and its impact on women's lives. In addition, it is necessary to promote policies and practices that promote equality and social justice in the sector.
Análise de algoritmos de construção de grafos em conjuntos de dados de alta dimensionalidade
(Universidade Federal de São Carlos, 2023-08-28)
Soares, Vitor Freitas Xavier
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Valejo, Alan Demétrius Baria
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https://lattes.cnpq.br/9546164790189830
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https://lattes.cnpq.br/1871335822766399
The rapid development and adoption of information technologies, such as the internet, have resulted in an explosion in data generation, significantly increasing the volume of new instances with various attributes. The vast number of attributes present in certain datasets does not necessarily imply better performance, as algorithm performance decreases as attributes are excessively added (Curse of Dimensionality). Therefore, in the field of machine learning, traditional clustering algorithms play a crucial role in analyzing such data by segmenting it based on similarities. A more recent approach involves associating graph construction algorithms with community detection algorithms. In this approach, graphs represent the relationships between the data, while community detection algorithms are responsible for revealing densely connected groups and identifying hidden patterns. In light of this, the aim of this study is to perform an analysis of graph construction algorithms combined with community detection on high-dimensional datasets. Synthetic datasets were used, with the primary evaluation metric being the normalized mutual information index (NMI). Additionally, datasets with different numbers of attributes, groups, samples, and overlap were evaluated to observe the effects of dimensionality on the results. Traditional clustering algorithms, such as K-means and Agglomerative Clustering, were considered as baselines for comparing the performance of others. The results indicated that graph construction algorithms combined with community detection algorithms are a viable alternative and even yield better results in some cases than traditional clustering algorithms for high-dimensional datasets.
Gestão de riscos em uma planta industrial de beneficiamento de ouro: estudo qualitativo com APR e HAZOP
(Universidade Federal de São Carlos, 2023-08-28)
Silva, Gabrielly Layla da
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Lima, Alice Medeiros de
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https://lattes.cnpq.br/0038936541518854
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https://orcid.org/0000-0001-5643-1780
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https://lattes.cnpq.br/8488642948378522
The gold beneficiation process comprises a series of stages, ranging from ore extraction to its processing stage. The activities involved carry a set of significant risks. These risks encompass everything from landslides, explosions, fires to environmental contamination, and impacts on the health of the workers involved. Furthermore, in recent years, numerous disasters in the mining industry have shown harmful consequences when risks are not adequately managed. In this context, risk management along with industrial safety plays an essential role in identifying, evaluating, and controlling potential deviations associated with the process, aiming to protect both workers and the environment. This involves the implementation of preventive measures to minimize accidents and prevent damages, thereby promoting the mining industry's social responsibility. In this regard, the study's purpose is to explore the fundamental concepts of risk management based on the APR (Preliminary Risk Analysis) and HAZOP (Hazard and Operability Study) methodologies. Through the APR methodology, 14 stages were evaluated, and 23 operational deviations were qualitatively identified, with 2 of them assessed as "critical" risks. In the HAZOP methodology, 29 nodes were assessed, and 45 operational deviations were identified, with 14 of them rated as "serious" risks. Furthermore, through the comparison between the two approaches, complementarity between APR and HAZOP was observed, emphasizing that the combination of techniques provides a more comprehensive understanding of the risks involved in gold beneficiation activities, allowing for the identification of critical points and the proposal of corrective actions.
Análise das ferramentas de controle de performance no trabalho à distância: estudo de caso em uma empresa de marketing digital
(Universidade Federal de São Carlos, 2023-08-28)
Bezerra, Alan dos Santos
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Fontes, Andréa Regina Martins
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https://lattes.cnpq.br/4848646681792317
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https://orcid.org/0000-0002-9670-6221
Remote work, characterized by working outside the company's accommodations, was intensified with the COVID-19 pandemic. Even with the end of the pandemic and the remission of isolation rules, this type of work was maintained in full or in part by many companies. Therefore, the objective of this study is to analyze the tools for evaluating remote work in a company in the digital marketing sector located in Sorocaba, state of São Paulo. The research uses a case study from a mixed and applied approach. The tools used by the company were evaluated from the workers' point of view through the application of a questionnaire and interviews addressing the advantages and advantages in employee performance control. As a result, it was found that the use of performance evaluation tools are well accepted and used by most teleworkers in the company, but negative points such as overwork, lack of direct supervision and lack of mental health were reported, so that companies continue to refine their performance measurement strategies and tools to reflect the specific needs of telecommuting.
Avaliação do aproveitamento energético dos resíduos da indústria de óleo de rícino por meio da cogeração
(Universidade Federal de São Carlos, 2023-08-28)
Estanislau, Diana Wendy Ré
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Queiroz, João Paulo Silva
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https://lattes.cnpq.br/7316247674511327
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https://orcid.org/0000-0003-3469-2773
The castor bean plant (Ricinus communis L.) is an oilseed crop from which castor oil is extracted, that has various applications, such as a bio lubricant, raw material for bioplastics and biodiesel, additive in coatings, cosmetic and pharmaceutical. In the processing of castor beans, in addition to the oil, several by-products are produced, including straw, husk (in the agricultural phase), and seed cake (industrial stage). The demand for renewable energy sources and products with a reduced environmental impact continues to grow. In this context, agro-industries have been studied according to the biorefinery approach, which seeks to utilize all parts of the plant to produce value-added products, minimizing waste disposal. Currently, the application of castor bean by-product is concentrated only on the use of seed cake as a biofertilizer or additive in animal feed. However, this and the other residues have energy potential that could be exploited. In this work, their use as sources for cogeneration was studied, seeking to evaluate the generation capacity of this industry, optimization factors of thermal cycles, as well as technical and environmental limitations involved. For this purpose, three systems were proposed and simulated in Aspen Plus software. They differ in terms of heat source: direct burning of straw and husk (in System 1) or anaerobic digestion of seed cake for biogas production which is then burned (in Systems 2 and 3); and in terms of the thermodynamic cycle used for cogeneration: Rankine (in Systems 1 and 2) and Brayton (in System 3). Based on an industry with a processing capacity of 100 thousand tons of seeds/year, the useful energy (work + recovered heat) obtained in Systems 1-A (husk and a portion of the straw obtained through manual harvesting), 2 and 3 was 24.5, 6.9 and 7.0 MW, respectively. And in case 1-B, which considers that all agricultural residue would be available for burning, the rate reached 91 MW. System 3 had low work output due to the limitation of combustion temperature to avoid NOx and CO emissions. In all evaluated scenarios, the castor bean industry would be self-sufficient in terms of its electrical and thermal energy usage.
Caracterização das práticas de cuidado em Saúde Mental de uma Comunidade Caiçara
(Universidade Federal de São Carlos, 2023-08-28)
Mendonça, Luiz Henrique Franco
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Garcia, Marcos Roberto Vieira
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https://lattes.cnpq.br/3911188481669270
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https://orcid.org/0000-0002-5668-2923
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https://lattes.cnpq.br/5329269139982367
Ilha do Cardoso State Park is located in the extreme south of the state of São Paulo, in the municipality of Cananéia. It has about 140 housing units, divided into specific communities of the traditional caiçara people, including Enseada da Baleia and Marujá. Geological and geopolitical changes, in addition to the recent pandemic of the new coronavirus, have altered communities' way of life, impacting their health and development. After a preliminary study using the current Psychosocial Care Network in the municipality, this research aimed to analyze the mental health care practices that the communities have, using the method of active participant observation of Rodas de Conversa in the communities of Enseada and Marujá. The qualitative analysis of the public data revealed the absence of public instituiions, either in the lack of specialized services, the difficulty in maintaining the river teams, or the lack of support to overcome limited situations. In the community of Enseada, the organization of the society and the continuous approach in its reconstruction after the compulsory change of location - which we interpret as a process of elaboration of a psychosocial trauma - generated the construction of more collective practices, such as the Dry Fish Workshop (which works along the lines of the Solidarity Economy) and the handicrafts, and which were appreciated as protective practices for the mental health of the people there. Such community care practices were not observed in the Community of Marujá, where many families do not have an associative bond and depend exclusively on informal work and social assistance benefits, leaving people more vulnerable concerning mental health problems. In both communities, care is predominantly exercised by women, generating an overload of activities, which reflects the gender inequalities observed by other researchers in Brazil and worldwide.
Efeito da adubação na qualidade do café: uma revisão de literatura
(Universidade Federal de São Carlos, 2023-08-28)
Corerato, Yago Lichtscheidl
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Verruma-Bernardi, Marta Regina
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https://lattes.cnpq.br/3470912236544684
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https://orcid.org/0000-0003-1375-0938
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https://lattes.cnpq.br/0730097355742529
This work conducts a bibliographical survey to analyze the effects of fertilization on coffee quality. In the literature review, the interactions between fertilization, crop productivity and coffee quality were explored. The results highlight the influence of fertilization in determining the quality of coffee, which can directly affect the productivity and quality of the coffee drink. Each nutrient playing a role is equally important. Balance in the application of nutrients is essential, as fertilization impacts the quality of the final coffee. Attention to soil fertilization, with technical improvement, is essential to obtain high quality coffees. This work contributes to the understanding of the factors that influence coffee quality and shows that fertilization plays an important role in coffee quality.
Conversão do glicerol a propilenoglicol utilizando catalisadores a base de cobre
(Universidade Federal de São Carlos, 2023-08-28)
Rodrigues, Luan Guilherme Dias
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Santos, João Batista Oliveira
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https://lattes.cnpq.br/0285313473901330
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https://lattes.cnpq.br/3531814663014122
The hydrogenolysis of glycerol is one of the main routes for the production of propylene glycol and will be the object of study of this work. In order to carry out a kinetic study aimed at increasing the glycerol conversion and the propylene glycol selectivity of the reaction, copper-based catalysts supported on zirconia, with different metal/support ratios, were used and they were synthesized by the coprecipitation method. The methods used for the characterization of the catalyst were thermogravimetric analysis, temperature programmed reduction and nitrogen physisorption. The reaction tests were carried out in a batch reactor and had their initial parameters defined from the literature, and they were the temperature of 200 ºC, pressure of 20 bar of hydrogen, reaction time of 4 hours, reaction volume of 20 mL, of which 20% of the mass was glycerol and the rest was water, and the catalyst mass of 350 mg. For the kinetic study, from the best performing catalyst, reactions were made by changing the values of one parameter at a time, and the alternative values of pressure were 5 and 10 bar, of temperature were 180 and 220 ºC, and the mass concentration of glycerol were 40, 60 and 80%. All the tests were performed, the catalyst with the best performance was the 60% ZrO2/Cu, with the values of 12.36% of conversion, 82.34% of selectivity to propylene glycol and a 10.18% yield of propylene glycol.
A democracia brasileira está ameaçada? Avaliação dos níveis de adesão à democracia entre os brasileiros
(Universidade Federal de São Carlos, 2023-08-28)
Pedroso, Gabriella Moraes
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Casalecchi, Gabriel Avila
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https://lattes.cnpq.br/9759794253878555
This work seeks to analyze adherence to democracy in Brazil and evaluate the hypothesis “Is Brazilian democracy threatened?”. For this, data from the Barometer of the Americas from 2002 to 2019, and data from Varieties of Democracy in Brazil (V-Dem) are used. In the end, we seek to analyze how the quality of democracy and political culture are related to adherence to democracy in this government system. This research becomes useful by contributing to current reflection on democracy and the anti-democratic actions that threaten its existence.
Caracterização agronômica de linhagens de pimentão (Capsicum annuum L.)
(Universidade Federal de São Carlos, 2023-08-28)
Tavares, Rafael Dantas Asbahr
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Sala, Fernando César
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https://lattes.cnpq.br/6771975466075202
Bell peppers are a popular vegetable in many cuisines around the world, known for their versatility and flavor. It is an excellent source of nutrients, including vitamins A and C, as well as containing fiber and antioxidants. Generally, the bell pepper market tends to be stable, with consistent demand due to its use in many culinary dishes around the world. However, prices and supply may vary depending on the region and growing season. Factors such as weather conditions, pests and diseases can also affect the production and availability of peppers in certain areas. Agronomic characterization provides useful information for the selection of lines developed in genetic improvement programs. The purpose of the present study was the agronomic characterization of pepper (Capsicum annuum) strains, with the aim of providing crucial information for the selection of strains aligned with production goals and market preferences. Six pepper lines (F511357, F511361, F511362, F511363, F511365, F51366) were evaluated in a protected environment, following a randomized block design (DBC) with 6 treatments and 3 replications, where each of the lines had 9 pots. Each strain was evaluated for its biometric characteristics, production and qualitative parameters. The results obtained revealed important differences between the strains, highlighting some of them due to their desirable characteristics, such as larger fruit size and pulp thickness, productivity. The study has undesirable characteristics, such as the presence of streaks in the fruits and anthocyanin, which affect the fruit ripening process. Therefore, the study contributed significantly to knowledge on the subject, offering a basis for making decisions when choosing the best pepper lines, which were the F511357 and F511361 lines due to the best fruit characteristics sought by the market linked to good productivity. Furthermore, the research expanded the understanding of the genetic diversity present in the strains studied, playing a fundamental role in the context of the genetic improvement of this crop.
A casa é deles?: reflexões sobre o cuidado em Serviços Residenciais Terapêuticos, a partir da perspectiva dos cuidadores
(Universidade Federal de São Carlos, 2023-08-28)
Muniz, Livia Prado
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Garcia, Marcos Roberto Vieira
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https://lattes.cnpq.br/3911188481669270
;
https://orcid.org/0000-0002-5668-2923
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https://lattes.cnpq.br/1423666700560288
The dehospitalization of people who have experienced extended stays in psychiatric hospitals and the possibility of them residing in Therapeutic Residential Services are strategies outlined by the Brazilian Mental Health Policy. Legislation concerning these services does not specify caregiver qualifications for employment in these residences, and there is no consensus regarding the necessity of specific training for these professionals. This research aimed to identify the existing conceptions of care among caregivers in Therapeutic Residential Services and promote reflections on them, highlighting the formative processes of these professionals and their work practices. The study was carried out in Salto de Pirapora, a municipality in the metropolitan region of Sorocaba, known for its high number of Unified Health System beds in psychiatric hospitals. Beginning in 2012, the municipality initiated a deinstitutionalization process, resulting in the closure of two asylums. A qualitative approach was used in this research, which involved conducting a literature review on the topic, followed by exploratory interviews and questionnaire administration with 18 caregivers from Therapeutic Residential Services in the aforementioned municipality. Furthermore, non-directive interviews were conducted with 4 of them. Four conceptions of care were identified, which are mixed in the caregivers' speeches: Care in its professional dimension, Care as an act of charity, Care as the execution of domestic tasks, feminine and maternal care. It became evident that diversity in care practices within Therapeutic Residential Services is expressed in a contradictory way, through actions that sometimes help to promote autonomy, and at other times homogenize care. Thus, it is urgent to develop formative paths for these professionals so that residents can increasingly assume the house as their own and according to their strengths and needs, care for and be cared for. The Permanent Education strategy is a powerful way to face the various challenges related to the care practices discussed in this research. It is expected that the discussions proposed in this study will contribute to the appreciation and qualification of caregivers' work so that deinstitutionalization processes are sustained from anti-asylum references based on respect and freedom.
Produção de bioquerosene de aviação: uma análise comparativa de diferentes processos tecnológicos
(Universidade Federal de São Carlos, 2023-08-28)
Pinheiro, Matheus Lucas
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Béttega, Vádila Giovana Guerra
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https://lattes.cnpq.br/0752059622240208
In the face of growing global concern about climate change and environmental events witnessed over the past decades, there arises an urgent need to seek alternatives that minimize the impacts of human activities, particularly concerning the ongoing use of fossil fuels. The aviation sector stands as one of the largest greenhouse gas emitters worldwide, prompting efforts to mitigate its environmental footprint. One of the alternatives to reduce emissions is the production of aviation biofuel, a renewable and sustainable fuel that can partially or completely replace conventional aviation kerosene. This work aims to analyze the technological processes available in literature and certified by competent bodies, with special emphasis on regional availability of raw materials, in order to identify the potential for implementing production frameworks within the country. In the current scenario, the HEFA pathway, utilizing soybeans as a feedstock, emerges as the most promising and viable short-term alternative for aviation biofuel production, while other oilseeds also exhibit potential for exploration in the medium to long term. Consequently, with governmental support through the enactment of resolutions incentivizing the production and replacement of non-renewable fuels, Brazil could solidify its position as a major biofuel producer, thus mitigating the impacts of the burgeoning aviation market.
Influência do tipo de lipídeo e peptídeo beta amiloide sobre a perturbação da membrana e consequências na toxicidade de células neuronais observadas pelas respostas luminescentes do complexo RuApy
(Universidade Federal de São Carlos, 2023-08-28)
Garcia, Maria Laura da Cruz
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Carlos, Rose Maria
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https://lattes.cnpq.br/1589143355309943
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https://orcid.org/0000-0002-0277-9789
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https://lattes.cnpq.br/5258277744651236
One of the hypotheses for the cause of Alzheimer's disease is the accumulation of amyloid-beta peptide (Aβ) aggregates in the brain that lead to severe synaptic and cognitive dysfunctions resulting in neurodegenerative dementia. Some studies indicate that the formation of amyloid plaques and Aβ peptide toxicity is associated with its interaction with the neuronal cell membrane. This interaction accelerates the aggregation process and generates pores in the cell membrane with the formation of oligomeric Aβ species. Studies in our laboratory have shown that the luminescent complex cis-[Ru(phen)2(3,4Apy)2]2+ (RuApy, phen = 1,10-phenanthroline, 3,4Apy = 3,4-diaminopyridine) protects cells PC12 against the toxicity of pore-like oligomeric species of Aβ1-40, changing the aggregation mechanism to a non-toxic pathway, leading to the formation of micelle-like structures. These results motivated the study of the influence of RuApy on the process of aggregation and toxicity of Aβ1-42 and to verify the possibility of involvement of RuApy in the mechanism of action of Aβ1-42 against the cell membrane. The studies carried out involved the spectroscopic techniques of absorption, steady-state emission and time-resolved in the UV-visible region, fluorescent image microscopy, circular dichroism and reflection-absorption spectroscopy in the infrared region with polarization modulation (PM-IRRAS). In this project, it was demonstrated that the RuApy complex has a protective effect for the human neuroblastoma cell line SH-SY5Y against toxic Aβ1-42 species, corroborating previous results that showed that RuApy alters the Aβ aggregation process leading to the formation of non-toxic fibrils. For the interaction studies between RuApy and the cell membrane, models of neutral lipid membranes, negatively charged, with cholesterol, marked with NBD and Texas Red organic dyes and in different media were used in order to elucidate how the complex interacts with the models of membrane. The interaction was evaluated by binding assays using fluorescence, supported lipid bilayers (SLB) and microfluidic devices. Using the Forster resonant energy transfer mechanism (FRET), the dissociation constant (Kd) of the interaction between RuApy and the lipid bilayer was determined and, according to the change in the constant, the influence of factors such as charge, fluidity of the membrane and hydrogen bonds in the interaction. The obtained results indicated that RuApy interacts with membrane models mainly through electrostatic interactions and hydrogen bonds. Molecular-level information on RuApy interactions with the lipid membrane was obtained in studies with Langmuir monolayers by superficial pressure versus area Isotherms and PM-IRRAS experiments and are consistent with the data obtained with SLBs in microfluidic devices. Altogether, the results indicate that the interaction of RuApy with the tested membrane models involves electrostatic and hydrogen bonding interactions, and that this interaction depends on the lipid composition. Also, that RuApy alters the aggregation and has an inhibitory effect on the cytotoxicity of Aβ1-42 against the SH-SY5Y cell line. Such conclusions suggest that the RuApy complex may play an important role in the interactions between the Aβ peptide and the cell membrane.
Impacto das práticas ESG na percepção dos trabalhadores: uma análise das práticas sociais corporativas
(Universidade Federal de São Carlos, 2023-08-28)
Paulo, Thaís Pereira
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Fontes, Andréa Regina Martins
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https://lattes.cnpq.br/4848646681792317
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https://orcid.org/0000-0002-9670-6221
The social practices of companies have become increasingly relevant to competitiveness in the business landscape, aiming to reconcile business success with the promotion of societal well-being through actions to improve social conditions, sustainable development, and stakeholder trust. The objective of this research was to understand how the main social practices adopted by companies affect workers' perception and engagement. To achieve this, a case study was conducted through interviews with employees of a service sector company. The results demonstrated that the majority of employees are aware of and engaged by the company's social practices, with a significant emphasis on actions related to Professional Development, Health and Well-being, Social Investment, and Equal Opportunity, respectively. It was concluded that there is a preference among workers for initiatives focused on professional development and career planning.
Avaliação do efeito da exposição ao cobre e diferentes cores de luz na composição bioquímica de Pediastrum sp
(Universidade Federal de São Carlos, 2023-08-28)
Neves, Camila de Almeida
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Solidade, Lucas
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https://lattes.cnpq.br/3866513568022265
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https://orcid.org/0000-0002-6808-0495
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Lombardi, Ana Teresa
Microalgae are organisms with morphological and phylogenetic diversity, which also vary in their biochemical composition. This diversity confers its use in sectors of economic relevance, such as nutrition, pharmaceuticals and cosmetics. In general, optimal conditions for growth are employed, but the cultivation can be manipulated in terms of its physicochemical characteristics, such as micronutrients and light conditions, to alter the metabolic response of the alga with the consequent alteration in the production of biomolecules. This work aimed at investigating the effect of copper and different light colors on the growth and physiology of the microalgae Pediastrum sp., focusing on the production of biomolecules. The copper concentration used corresponded to the EC20, calculated through tests in a 96-well microplate with 30 concentrations ranging from 4.10-8 to 9.10-4 M nominal copper, with absorbance monitoring for 6 days. Once the concentration was defined (EC20, 7.5.10-7 M), the algal physiology experiment was carried out. The determination of biomolecules in the biomass was done in 96 h cultures, including the blue, red and white LEDs as variables. After this period, chlorophyll a, chlorophyll b, carotenoids, proteins and carbohydrates in the biomass were quantified. The results showed that blue light favoured the biosynthesis of carotenoids and carbohydrates and, in association with copper, significantly increased the concentration of chlorophylls. Copper at a concentration equivalent to EC20 influenced the photosynthetic process, increasing photochemical dissipation (qP) independent of light color, and non-photochemical dissipation (NPQ) for white and red lights. The results presented in this study contribute to the expansion of knowledge about the combination of copper and light colors in the physiology of the Chlorophyta Pediastrum sp., as well as in the production of biomolecules and microalgae biotechnology.
Segurança de bioinseticida a base de Beauveria bassiana para a abelha sem ferrão Scaptotrigona postica (Hymenoptera: Apidae, Meliponini)
(Universidade Federal de São Carlos, 2023-08-28)
Silva, Camila Aparecida
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Montagnolli, Renato Nallin
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https://lattes.cnpq.br/7455124733755299
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Nocelli, Roberta Cornélio Ferreira
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https://lattes.cnpq.br/8934724759636382
Brazil is currently home to 259 species of stingless bees, including Scaptotrigona postica, known locally as black mandaguari. This species plays a crucial role in the pollination of crops. However, it faces threats due to exposure to pesticides. The use of the fungus Beauveria bassiana for biological control has gained prominence seeking more sustainable agricultural practices although its safety for bees is not yet fully understood. This study focused on evaluating the safety of the B. bassiana-based bioinsecticide on adult S. postica bees. The main objective was to determine the median lethal dose (LD50) and the median lethal concentration (LC50) of the bioinsecticide at different concentrations by topical and oral exposure, being validated by a positive control, the pesticide dimethoate, and verify and compare the viability and presence of viable conidia with data from the manufacturer using microbiological techniques. Statistical analyses employed a generalized binomial model to construct dose-response curves and non-parametric tests to assess the significance of concentrations in the negative control. Toxicity was more pronounced at a concentration of 20 µg/µL, being 100 times higher than that in the field, both through contact and ingestion, evidencing a correlation between concentration and probability of mortality. The estimated LD50 of B. bassiana for S. postica was 2.3900 µg/µL, 11.95 times higher than the field dose. Similarly, LC50 was 2.9736 µg a.i./bee, 14.87 times higher than the field concentration of 0.2 µg/µL. The formulated bioinsecticide demonstrated high viability in a nutrient medium, guaranteeing its quality. The results suggest the possibility of defining safe levels for non-target organisms although higher concentrations of the B. bassiana-based commercial product present higher toxicity. It is fundamental to promoting agricultural sustainability and the preservation of bees, which are essential for healthy ecosystems and food security.
Desenvolvimento de um videocurso sobre o software de simulação LTspice
(Universidade Federal de São Carlos, 2023-08-28)
Silva, Gabriel Santos da
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De Francisco, Carlos Alberto
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https://lattes.cnpq.br/1246572405382250
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https://orcid.org/0000-0001-6472-5957
This article describes the creation of an introductory video course on the LTspice circuit simulation software, with a focus on meeting the learning needs of students and electronics enthusiasts. The course comprises eleven videos covering topics from the initial download to advanced subjects, and emphasizes the significance of this educational resource for the Electrical Engineering community. Furthermore, it highlights the potential to establish a culture of video course creation as part of an extension activity.