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Production and microstructure-property correlations in mono-oriented bacterial cellulose membranes
(Universidade Federal de São Carlos, 2024-03-07)
Fan, Anderson Zhong
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Otoni, Caio Gomide
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https://lattes.cnpq.br/9403804691367376
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https://orcid.org/0000-0001-6734-7381
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Mattoso, Luiz Henrique Capparelli
The development of naturally occurring biodegradable materials has increasingly attracted the attention of researchers in recent years owing to the rising environmental concern. Among these materials, bacterial cellulose (BC) stands out as an easily obtainable polysaccharide mat with potential for application in several areas. Nanocelluloses, regardless of origin, are known to form gels in aqueous systems that, when dried, consolidate into materials stabilized both by the entanglements themselves and by hydrogen bonds between adjacent particles, the latter strongly dependent on the degree of interfibrillar orientation. Because of the above, this research aims to promote mechanical anisotropy at different levels through the preferential orientation of BC nanofibrils, achieved by asymmetric drying. The BC membrane was dried either in a “free” or “restricted” fashion within an atmosphere of controlled temperature and relative humidity. Different degrees of pre-stretching were also investigated to enhance the mechanical resistance and stiffness in the direction of the drying restriction. The resulting materials will be characterized concerning morphology, structure, and mechanical properties through scanning electron microscopy, polarized infrared spectroscopy, polarized optical microscopy, X-ray diffraction, and dynamicmechanical thermal analysis. Promising conditions and potential applications will also be discussed and analyzed.
A avaliação do Saresp e os desafios do retorno em meio á pandemia no Brasil
(Universidade Federal de São Carlos, 2024-03-07)
Araújo, Naraiany Aparecida Garcia Machado de Assis Pires de
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Baldin, Yuriko Yamamoto
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Sampaio, João Carlos Vieira
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https://lattes.cnpq.br/8286887389013685
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https://orcid.org/0000-0002-0318-6790
The Coronavirus pandemic, COVID-19, had a major impact on Brazilian education, being affected not only in educational issues but also in the context of socialization as individuals. This work was developed along with the 9th year A, a classroom from a State Public Country School, located in the central region of Cravinhos-SP. It aims to evaluate, list and improve skills that are lacking during the mandatory in-person return. Using the BNCC as a guiding document, a quiz was prepared with questions from Saresp, accessing previous years tests addressing the skills that are relevant for the 9th grade. The aim of this work was to recover skills that were lacking, so that each student could identify their errors in the assessed activities, thus obtaining the expected solution. However, it was not possible due to the Men’s Football World Cup, which suspended classes. The results presented show a generation that is resistant to manual calculations and impatient when facing errors.
A Geografia dos lugares e das paisagens na perspectiva das experiências e sentimentos no percurso do romance "No caminho de Swann" de Marcel Proust
(Universidade Federal de São Carlos, 2024-03-07)
Domingos, Edson Lopes
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Domingos, Edson Lopes
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Mariano, Neusa de Fátima
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Mariano, Neusa de Fátima
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https://lattes.cnpq.br/50037433018447104
The search is found in between at the debates and dialogues with the Geography and the Literature refunded by place and landscape through novel writing, which become fundamental in our reflections. In the novel “There sides of Swann” by Marcel Proust, we presente the names Charles de Swann and Odette. The places, such as Balbec on the beach and Combray, a small town are places from the narrator´s childhood. Our theorical structural is based on Cultural Geography, which occupy your with diferente aspects of culture in the analisis of socio-spatial phenomena. We take in an depth dialogue trough the marks left by geographers such as Dardel (2015) reffering to lived espace, and Brousseau (1996). When rescue the reading of places and landscapes mobilized by reflections on the writing of literary autors. In the research, a set of experiences and feelings lived by the characters were collected in a qualitative way, we limited our studies Only in the first volume in the face at the trajectory how the characters perceived the landscape and the place, in order to be contributory to understanding how Society creates forms of organizing geographic space. Thus, the literary text becomes an object of analisis with the material scope, in addition to constituting inherent to internal and external aspects in the understanding of concepts fundamental concepts in Geography that contribute to Geographic Knowledge. Underlying this, it´s presente in the section to bring one for qualitative analysis due to the scientific contente required by the reader, by bringing delight and a way of doing Science.
Break of reciprocity on the light scattered by a disordered atomic cloud
(Universidade Federal de São Carlos, 2024-03-07)
Magnani, Pedro Henrique Nantes
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Teixeira, Raul Celistrino
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https://lattes.cnpq.br/6108339817883159
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https://orcid.org/0000-0001-8358-861X
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https://lattes.cnpq.br/9077123761403486
This study delves into interference phenomena, specifically exploring interference patterns arising from light scattered by a disordered assembly of cold atoms. The investigation focuses on disrupting optical path reciprocity within a mirror-assisted Coherent BackScattering setup (mCBS), where light scattered by a large cold atomic cloud interferes with its mirror image. The introduction of non-commuting polarizing optics, such as a birefringent mirror and a half-waveplate, reveals a reduction in contrast in the fringes, uncovering a geometric interpretation on the Poincaré sphere. The study examinated intensity profiles and fringes in two different clouds: a magneto-optical trap (MOT) based on the 689 nm transition and another on the 461 nm transition. The analysis involves fitting measured curves and understanding contrast reduction and phase shifts related to polarization changes. The study also explored the Pancharatnam-Berry phase, determining its impact on reciprocity in the system influenced by factors like finite optical density and the saturation parameter. The non-commutation of polarizing optics emphasizes the dependence of reciprocity on specific values of parameters. The mCBS configuration offers a distinctive setup, enabling the straightforward introduction of such non-commutative optics. Despite uncertainties, the agreement between theoretical predictions and experimental data validates the robustness of the study, providing valuable insights into the intricate interplay of experimental parameters and system characteristics. In a broader context, the experimental findings underscore the vectorial nature of light as a powerful tool for manipulating the reciprocity of interfering paths, impacting interference while preserving spectral and spatial coherence. This study opens avenues for further exploration in this complex and nuanced research domain.
Implementação de Protocolos de Sustentabilidade em Trabalhadores que atuam no Trabalho Remoto
(Universidade Federal de São Carlos, 2024-03-07)
Barbosa, Anderson Tadeu
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Faria, Luiz Carlos de
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https://lattes.cnpq.br/2656343277991754
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https://orcid.org/0000-0003-1157-3528
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Hayashi, Carmino
Remote work is a mode of employment that has existed for years. Some companies adopt this form of work for a variety of reasons, among which we can highlight functional well-being, mobility, productivity, etc. The adoption of remote work was on the rise, and with the advent of Covid-19, due to the need for social isolation, many companies and their employees had to adapt immediately and emergently to remote work. People began to carry out their daily activities in an environment distant from the conventional one, in most cases, in their own residence. This change occurred without any type of preparation or guidance from the perspective of sustainability. People adapted their conditions to the moment, in order to be able to continue in the face of the challenges of that scenario. The objective of this work is to verify the change in people's behavior, from the application of an environmental sustainability protocol in remote work. This study presents the relevance of implementing protocols or orientation materials focused on sustainability in the context of remote work, aiming at the awareness of collaborators. Through the application of a longitudinal study, using the panel method and multiple correspondence analysis, it was possible to identify the indication of change in participants' behavior. The results indicate that, after the application of the protocol, all participants adopted or intensified the frequency of adopting sustainable practices in their remote work environment, contributing to a more sustainable professional daily life.
Jovens entre “o ser e o vir a ser”: projeto de vida, programa ensino integral e terapia ocupacional social no ensino médio
(Universidade Federal de São Carlos, 2024-03-08)
Reis, Stéphany Conceição Correia Alves Guedes
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Lopes, Roseli Esquerdo
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https://lattes.cnpq.br/1507752191797249
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https://orcid.org/0000-0001-9572-4586
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https://lattes.cnpq.br/5054911281522128
In Brazil, since the “First Republic”, education has undergone reforms that affect everyone levels, including high school. At the heart of these reforms, this level of education is traditionally marked by educational dualism, reproducing the power structures present in Brazilian society. To accentuate the differences, Brazilian high school is made up of different types of schools, which, in general, correspond to the social classes for which they are intended, such as the Integral Education Program (PEI) school, established by Department of Education of the State of São Paulo in 2012, which, in a pioneering way in the country, directed the curricula of the final years of elementary and high school towards protagonism of students around what were called “life projects”. This Program influenced the last reform of high school in the country, introduced in 2018, delegating to this level the function to subsidize young people in building their future projects. Taking this context, we return to understanding the offer and contours of the “Life Project” discipline in public high schools that, in 2021, were part of the PEI, linked to the Directorate of Teaching in the São Carlos Region, São Paulo (DER - São Carlos), from the perspective of DER, of the vice-principals, responsible for the life project axis in schools, of the teachers of this discipline and young people. We seek to understand the motivations, means, meanings and purposes of teaching high school youth how to plan their lives, as well as enabling production of subsidies to compose the “Life Project” discipline in dialogue with interests of young people and with the components of Basic Education in Brazil, having as reference to the theoretical-methodological contributions of social occupational therapy to support therapeutic-occupational actions in these schools. The data were collected/produced in a sequence of steps that involved the description and analysis of official documents regarding advocates Basic Education in Brazil, as well as those related to the PEI, interviews, questionnaires, dialogues and conversations in collective meetings and the holding of “Workshops of Activities, Dynamics and Projects” and “Singular and Territorial Monitoring”, technologies that have been proposed by social occupational therapy. The “Studies of Youth” have been configured as a field of interface between several areas that have, in one way or another, the “School” and its processes as a point of debate. With experiences developed so far, we defined the Life Project discipline, in the public school of the PEI, based on the phenomenon of ambiguity, since it holds the formative potential for serve young people’s reflection on their living conditions, their ethical values, their training and professional choice in a situated and critical way, in the same way that it can be at the service of the deepening of the structural inequalities of capitalism and market interests, reaffirming the permanence of educational dualism in high school, which, above all, does not effective full and disinterested training for the majority of young people who seek public school references for a better life, often made unfeasible by the place in which it is located. occupies and from where the future can be projected. Based on the survey and analysis of the normative texts of the PEI, we argue that the curricular component Life is a potential space for discussion, reflection and broadening perspectives of future of young people and knowledge of themselves and the world. In this way, we highlight the potential for social occupational therapy to work with young people in public schools, through presentation and discussion of the actions carried out in the schools that made up the empirical field of the research that supports this thesis in the Life Project discipline, with the “Workshops de Activities, Dynamics and Projects” and with “Singular and Territorial Monitoring”. It becomes possible with such actions to highlight the formative nature of the discipline to promote reception, dialogue, debate, recognition, social care, in addition to strengthening social support networks, working on future projects among these young people in an expanded way, envisioning the autonomy, citizenship and formation “for themselves” of these subjects.
A dimensão estética na educação ambiental: Uma análise a partir da pedagogia freireana
(Universidade Federal de São Carlos, 2024-03-08)
Oliveira, Clarissa Suelen
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Silva, Antonio Fernando Gouvea da
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https://lattes.cnpq.br/9621931288117213
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https://orcid.org/0000-0002-8915-9952
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https://lattes.cnpq.br/0155429220877053
Aesthetics is a historical factor that is very present in our daily lives, but little discussed when it comes to education. The inseparability of educational concepts with aesthetic values is a premise from a perspective of Historical and Dialectical Materialism, since values are intrinsic to any parameter and dimension of contemporary society. In this thesis, aesthetic values were discussed and articulated with the concept of Environmental Education, which, in a critical, dialectical and transformative vision, understands and defends that the subjects' worldview and their social, cultural and historical factors must be the foundation of the knowledge construction process in educational institutions. In this way, based on bibliographical research in the literature of the area and experiences, analysis categories were constructed (authentic praxis, otherness and critical-humanizing sensitivity) for the investigation of examples of research on the subject, to analyze the relevance of the assertions, associated with aesthetic values, in the educational context. To this end, research was carried out in educational databases, books and articles that discussed this subject, thus allowing us to investigate a field little explored in academia. The works analyzed had some elements that consider aesthetic aspects. However, there was no explicit and, often, implicit contemplation of all aspects in the texts. That said, it is understood that the theme involving the relationship of Critical Environmental Education, from a Freirean perspective, based on Historical and Dialectical Materialism that addresses aesthetic issues, is still scarce in academia. Therefore, other studies are suggested that look at the context and seek to report the factors of oppression, exploitation, exclusion, vulnerabilities and wide open inequalities of the current social system, and also announce propositions for social transformations that education has the potential to provide, based on authentic praxis, in critical-humanizing sensitivity and in the alterity between subjects, that aim at the emancipation of subjects and humanization.
Os mundos de Maracanã: obrigações, medos e transformações urbanas numa região da ilha de São Luís-MA
(Universidade Federal de São Carlos, 2024-03-08)
Alcobaça, Luzinele Everton de
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Toledo, Luiz Henrique de
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https://lattes.cnpq.br/5366260223109463
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https://lattes.cnpq.br/2518847975737313
Previously conceived as a settlement, Maracanã region (Maranhão, Brazil) is now composed by districts considered as rural and outskirts in the relation they establish with the urban centers of the region. Maracanã, Alegria and Vila Mochel share political, historical and cultural specificities concerning their flow of knowledge and people in varied contexts. Between 2013 and 2018, thousands of houses were built in the region through the Brazilian Social Housing Program “Minha Casa Minha Vida”. This was something producing an environmental impact in the swamps, rivers and juçara forests, in addition to producing a tension in the daily lives and traditional practices of its population. This research departs from the biographies of different families living in the districts of Maracanã and from my own experiences as an eventual dweller of the region. Then, I analyze the meanings of inhabiting places where the contexts of urban development and multiple devastations are present. These meanings are taken as outcoming from expanding urbanity and an advancing world that hesitates the possibilities of inter-knowledge and intersubjective trust. The reflections raised by my interlocutors make it evident the fears produced through relating. The obligations they comply with the catholic saints – which are expressed in the domestic space – potentially confront the fear of an urban violence to which the districts are associated when they dynamize a constrained spatiality. After all, it’s less likely that the fear of human actions domains us when the excess of religious happiness makes us feel like we’re in a good company
Toxicidade de metais: uma avaliação em níveis molecular, individual e riscos para os ecossistemas aquáticos da Amazônia
(Universidade Federal de São Carlos, 2024-03-08)
Gomes, Diego Ferreira
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Moreira, Raquel Aparecida
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https://lattes.cnpq.br/4388003923600701
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https://orcid.org/0000-0001-9392-8067
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Rocha, Odete
The continuous entry of metals into aquatic ecosystems is a global reality, exacerbated in developing countries. In Brazil, especially in the North region, where most of the Legal Amazon is located, multiple pollution sources have multiplied for decades, posing risks to the aquatic biota. In this perspective, ecotoxicological studies, including the use of biomarkers, and ecological risk assessment protocols, can provide relevant information about the environmental conditions of aquatic ecosystems in this biome. Thus, the main objective of this study was to describe a new species of ostracode and assess its acute sensitivity to metallic salts (CuSO4, CdCl2, HgCl2, ZnCl2), both individually and in combination, as well as to evaluate if environmentally relevant concentrations induce oxidative stress. Finally, an ecological risk assessment protocol was conducted to examine the risks associated with exposure to these metals. Individuals of the species Strandesia rondoniensis used in this study were collected in the Natural Park of Porto Velho, in the Amazon region (state of Rondônia, Brazil), acclimatized, and cultured in laboratory. The growth and reproduction rates of eleven adult individuals of S. rondoniensis were analyzed. The ecotoxicological evaluation involved the simultaneous exposure to each metal individually and in a mixture, through a factorial design for toxicity with 25 different combinations over 48 hours. For the ecological risk assessment, concentrations of metals measured in the waters of various aquatic environments in the Amazon basin were considered based on the risk quotient values. Furthermore, investigations into the responses of biomarkers (Reduced Glutathione – GSH, Lipoperoxides – LPO, Metallothionein – MT, Superoxide Dismutase – SOD, and DNA Strandbreak) were conducted for all metals. The results of taxonomic identification of the species showed a high morphological resemblance to Neostrandesia striata and Bradleytriebella lineata, even though the new species belongs to Strandesia genus, indicating evolutionary convergence. Life cycle analysis showed that individuals of S. rondoniensis exhibit rapid growth and high reproductive rates, favoring their use in laboratory studies. The ecotoxicological results indicated that the toxicity gradient of metals was Cd > Hg > Cu > Zn. Toxicity in the mixture showed that the combination of Cu-Cd and Cu-Zn fit the model better (CA), indicating primarily synergism when copper predominated in the mixture. Meanwhile, the Cu-Hg interaction fit the model better (IA), again indicating synergism when copper was at a higher concentration. The survey conducted in this study shows that, although metal concentrations in the water were generally low, these values were well above the limits established by current national legislation in many areas, showing higher concentrations for the metals Co, Pb, Cr, Cu, and Ni. Concentrations of Mn, Cu, Ba, Pb, Co, Ni, Cr, Zn, Cd, and As were particularly high in sediment for various evaluated environments. Ecological risk assessment for the water compartment revealed that 56% of the studied areas presented a high risk (RQ>1) for aquatic biota. In sediment, 66% of the locations showed high risk and 40% medium risk (RQ = 0.1-1). The contamination factor indicated that 49% of the sampling points showed high contamination, and only 24% showed low contamination. Furthermore, sublethal exposures showed that the antioxidant and detoxification system (SOD, GSH and MT) were activated by exposure to metals; however, not enough to contain oxidative damage; thus, increasing LPO levels, resulting in DNA breakage. Therefore, the continuous contamination of aquatic ecosystems in the Amazon region represents a concerning threat to aquatic biota, as the concentrations found in our study are considerably above tolerance limits for many species, especially for the ostracode S. rondoniensis used in this study.
Síntese de derivados indólicos e avaliação frente ao Plasmodium falciparum
(Universidade Federal de São Carlos, 2024-03-08)
Januário, Marcelo Augusto Pereira
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Corrêa, Arlene Gonçalves
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https://lattes.cnpq.br/7425467156776144
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https://orcid.org/0000-0003-4247-2228
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https://lattes.cnpq.br/3346840663135691
Malaria is an infectious disease that leads to an acute, life-threatening condition. It is caused by protozoa of the genus Plasmodium and transmitted by the bite of female mosquitoes of the genus Anopheles. N-heterocycles are common in pharmaceutical industry, such as the indole nucleus, present in several drugs and occupying a notable position with respect to the generation of new antimalarial agents. Indole derivatives functionalized at the C-2 position are among the most active compounds against P. falciparum. C-H activation protocols at C-2 of indole with electron withdrawing groups have been widely studied and, through them, direct functionalization of the ring is achieved without the use of drastic reaction conditions. Nitrocompounds are a window of opportunity in organic synthesis and enable rapid access, for example, to amines via reduction, which can be trapped in situ to lead to functionalized products in a one pot fashion, a strategy commonly applied in the synthesis of Ugi adducts. This work aimed to synthesize 2-nitroalkylindoles through the development of a protocol for alkylation of indole at C-2 with nitrostyrenes via C-H activation and subsequent synthetic modification - Ugi reduction and condensation - of the nitro derivatives for the synthesis of peptidomimetics, towards the search for active compounds against the 3D7 strain of P. falciparum. Regarding the C-H activation reaction, a method was developed for the synthesis of (2-(2-nitro-1-phenylethyl)-1H-indol-1-l)(pyrrolidin-1-yl)methanones, catalysed by Rh( III), obtaining a total of 18 compounds, with yields between 39 and 80%. Next, the reduction of nitroalkylindoles to the corresponding amines was studied. Once the optimal condition for reduction was found, studies of the Ugi reaction began, which culminated in the synthesis of 14 compounds, with overall yields between 22 and 71%. Finally, the antiplasmodial activity of the synthesized compounds was performed against P. falciparum, and promising results were obtained with the peptidomimetics, motivating the synthesis of new adducts to contribute with the structure-activity relationship studies. Based on the skeleton of the most active compound, twenty-one compounds were prepared in 37 - 94% yield.
"Precisa ter gente!" Uma análise do MST e das crianças Sem Terrinha
(Universidade Federal de São Carlos, 2024-03-08)
Rudi, Luciana de Matos
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Cohn, Clarice
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https://lattes.cnpq.br/1714080901123094
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https://orcid.org/0000-0002-5446-7891
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https://lattes.cnpq.br/0683360221239571
This doctoral thesis aims to present the conception of childhood and children within the Movimento dos Trabalhadores Rurais Sem Terra – MST, based on the formulations made by the Movement itself, as well as the reflections of the "Sem Terrinha" children. The manner in which they engage with this conception, as well as the physical, symbolic, and political space they occupy within the organization, are elements discussed in this study. To achieve this, two “Encontros das Crianças Sem Terrinha" (Gatherings of the Sem Terrinha" children) were ethnographically studied, and educational documents and programs created by and for them were analyzed. This includes live broadcasts and programs, especially during the [voluntary] isolation periods of the pandemic, where ethnography was predominantly virtual. Furthermore, the thesis establishes a connection between the actions of the children and the broader initiatives undertaken by the MST in the struggle for land through popular agrarian reform, political agenda setting, and proposals to postpone the end of the world by creating a new world, with agroecology as a foundational national project. In this sense, the "Sem Terrinha" children emerge as significant agents of change, actively participating alongside the Landless Workers on various fronts.
Estratégias preventivas de eventos adversos com medicamentos potencialmente perigosos em hospitais: uma revisão de escopo
(Universidade Federal de São Carlos, 2024-03-08)
Santos, Geovana Oliveira Anschau dos
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Zem-Mascarenhas, Silvia Helena
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https://lattes.cnpq.br/0185144417072417
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https://orcid.org/0000-0001-7753-6725
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https://lattes.cnpq.br/7068345126847973
Potentially Hazardous Medications, also known as high-alert medications, are considered to have an increased risk of causing significant harm to patients through adverse events. The multidisciplinary healthcare team plays a substantial role in risk management and the development of effective strategies to prevent these adverse events. Objective: To map the scientific production on the use of strategies to prevent adverse events with Potentially Hazardous Medications by multidisciplinary teams in hospitals. Method: This is a Scoping Review guided by the recommendations of the Joanna Briggs Institute and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. Searches were conducted from November 2023 to January 2024 in the following databases: Cumulative Index to Nursing and Allied Health Literature; Latin American and Caribbean Health Sciences Literature; PubMed/Medline; Scopus. Grey literature included the analysis of dissertations and theses published in the Capes Theses and Dissertations Portal and EBSCO Open Dissertations. Results: Initially, a total of 1,687 studies were identified, but only 14 studies were included in the review. After reading and extracting data, contents were grouped based on their similarities and differences, resulting in three categories: Potentially Hazardous Medications risk management; Healthcare professionals' knowledge deficit about Potentially Hazardous Medications; Strategies in preventing adverse events with Potentially Hazardous Medications. Conclusion: This scoping review mapped the use of preventive strategies for adverse events with Potentially Hazardous Medications by multidisciplinary teams in hospitals. In summary, the reviewed studies indicate that a multifaceted approach involving pharmaceutical intervention, patient safety committees, the use of technologies, standardized classification, the establishment of barriers and alerts, and continuous professional training are the most effective strategies in preventing adverse events related to Potentially Hazardous Medications.
Educação empreendedora em um plano de negócios: experiência no ensino fundamental II
(Universidade Federal de São Carlos, 2024-03-08)
Silva, Conrado Valdovando da
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Salvador, José Antonio
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https://lattes.cnpq.br/2487171069472158
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https://orcid.org/0000-0003-3217-5035
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https://lattes.cnpq.br/7861140400209619
In this project, we conceived, executed, and analyzed a didactic sequence that integrated various methodological approaches, notably the use of digital technologies and problem-solving. Our aim was to explore themes of educational entrepreneurship and financial education, as well as fundamental mathematical concepts such as fractions and percentages. With meticulous planning, we designed activities that established strong connections between entrepreneurship, financial education, and the relevant mathematical concepts involved. The core of this planning was to emphasize the practical application of these abstract concepts, so they could manifest in the students' reality. With meticulous planning, we designed activities that established strong connections between entrepreneurship, financial education, and the relevant mathematical concepts involved. The core of this planning was to emphasize the practical application of these abstract concepts, so they could manifest in the students' reality.
Síntese de nanopartículas por métodos microfluídicos
(Universidade Federal de São Carlos, 2024-03-11)
Gomes, Nícolas Moreira de Carvalho
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Cordeiro, Marco Aurélio Liutheviciene
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https://lattes.cnpq.br/4787678071396324
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https://orcid.org/0000-0001-6287-3083
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https://lattes.cnpq.br/4699827186889924
Obtaining micro and nanoparticles with high structural and chemical control is in great demand given the continuous need to increase the performance of a series of processes and devices. The most common processes for synthesizing nanostructures consist of bottom-up processes, especially for the synthesis of silicon dioxide (SiO2), which are among the metal oxides applied in biomedical areas. Such methods make it possible to obtain particles with monodispersed and particles with nanometric dimensions. To achieve this, the synthesis of nanoparticles must be well controlled with well-defined parameters so that the properties of the final material are not affected. One approach to increasing efficiency in obtaining particles is continuous flow synthesis, and a tool for this is the use of microfluidics, however, related research is still not properly appreciated by the materials development community, representing an area that must still be properly explored, so that synthesis protocols are well established. This work aims to investigate the production of nanostructured particles of metal oxides, especially SiO2, from a microfluidics device, correlating the experimental parameters and characteristics of the device. Initially, the microreactor was obtained using a do-it-yourself (DIY) approach using more accessible materials than the traditional methodology, with the architecture designed in CAD. Subsequently, the influence of the concentration of precursors, from the same stock solutions, and the increase in the flow of reagents inserted into the microfluidics system was investigated. Finally, it was possible to observe particles with an average size between 78 and 118 nm and with low dispersion, much smaller than when obtained by the traditional batch method.
Estudos do reaproveitamento térmico do bagaço de laranja: secagem em leito de jorro modificado e peletização
(Universidade Federal de São Carlos, 2024-03-11)
Pinto, Guilherme Henrique Alves
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Freire, José Teixeira
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https://lattes.cnpq.br/2270677706718167
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https://orcid.org/0000-0002-8412-6801
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Freire, Fábio Bentes
The use of biomass as an alternative source of renewable energy has been gaining ground and leading to innovations in the production sector, seeking to support sustainable development and dispose of waste that was previously discarded. Brazil stands out as one of the world's leading producers of oranges, being the largest exporter of juice. Orange pomace, an abundant by-product with largely untapped potential as a biofuel, requires technical improvements to render its use viable. The present work aimed to evaluate the drying of orange pomace in a spouted bed to obtain dry biomass for pelletization. This evaluation involved studying the influence of a CaO mixture combined with pressing as pre-treatment, assessing the fluid dynamics in both the conventional spouted bed (LJC) and the spouted bed with mechanical agitation (LJMM) equipped with inclined blades, with variations in the bed's static height. Drying experiments were conducted in the LJMM, altering air temperature from 40 to 80 °C and air flow from 1 to 5 times the minimum spout velocity. These variations were analyzed for their impact on drying time and the quality of the resulting pellets. The obtained dry biomass underwent pelletization using three distinct strategies to enhance its physical and mechanical properties: particle size reduction, inclusion of binders, and torrefaction. The pellets were subjected to characterization tests measuring durability, impact resistance, density, water absorption, as well as aging properties such as changes in color, density, and humidity over time. The addition of quicklime with pressing removed 31.7% of the initial moisture from the bagasse, facilitating some movement in the LJC. However, the process faced instability due to biomass cohesion. Mechanical agitation proved essential in enhancing operational stability by agitating the entire bed, increasing stability, and eliminating fines carryover, up to 11.65% for LJC, allowing for a bed height of 27 cm, higher than the maximum 21.1 cm for LJC. Fluid dynamics analysis for the LJMM indicated an increase in pressure drop with rising bed height, while this correlation was absent for the minimum operating speed. This suggested that agitation primarily facilitated particle motion and air movement expanded the bed. The LJMM's operating air velocity was measured at 1.10±0.14 m/s, significantly lower (90%) compared to the minimum spout velocity required for a 21.12 cm height (11.11 m/s). During biomass drying, saturation of moisture in the gas stream at the LJMM exit highlighted efficient energy utilization, signifying an adequate airflow supplied to the system. Temperature and drying air flow showed no significant influence on pellet properties. Pellets produced from dried bagasse failed to attain desired physical and mechanical properties, necessitating particle size reduction to eliminate predetermined fragility points due to coarse particles. Strategies involving the addition of solid carbohydrates and mixing with coffee grounds altered pellet mechanical properties but fell short of achieving desirable values. Torrefaction imparted some hydrophobicity to the biomass, ensuring adequate water absorption, albeit resulting in fragile pellets. The addition of molasses enhanced pellet density and strength, but pellets expanded during a 30-day storage period. However, the addition of pure water or gelatinized starch produced resilient pellets, exhibiting high durability and impact resistance, maintaining structural integrity even after storage. These pellets also met the density threshold of 1200 kg/m³ with minimal color variation. These outcomes underscored the significance of moisture as a binding agent, allowing for the integration of drying and pelletization, ensuring an economically and operationally viable process.
Planificação de superfícies poliédricas no cálculo de distâncias
(Universidade Federal de São Carlos, 2024-03-11)
Rosa, Marcus Vinícius Fontes de Aquino
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Massago, Sadao
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https://lattes.cnpq.br/1915704875970931
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https://lattes.cnpq.br/8153087447730131
This work proposes the calculation of the length of the shortest possible trajectory connecting two points on the surface of a straight rectangular parallelepiped. One of the points belongs to a face and the other belongs to another face, adjacent to the first. The initial step of the solution is to identify the minimum trajectory, that is, to know exactly where it passes, and the other is to obtain its measurement. To identify the trajectory, a plan is carried out, so that the two adjacent faces are contained in the same plane. As a resource for calculating the length of this trajectory, this work suggests the Pythagorean Theorem or the Similarity of Triangles as a tool. A mathematical modeling of this problem will be proposed by calculating the shortest length of a conduit running from a lamp on a room's ceiling to the lamp switch on one of the room's walls. The concepts of Plane and Spatial Geometries accessed in the consideration and resolution of the problem are considered and presented, which serves as motivation for teaching and learning such concepts. Other similar situations will be suggested, such as, for example, the measurement of a minimum trajectory traveled on the lateral surface of a straight cylinder.
Análise de agrupamentos para dados espectrais
(Universidade Federal de São Carlos, 2024-03-11)
Silva, João Pedro Alvarenga Ramos da
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Souza, Camila Pedroso Estevam de
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https://lattes.cnpq.br/7665731855194346
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Andrade Filho, Mario de Castro
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https://lattes.cnpq.br/6518161034709249
Spectroscopy is the study that uses techniques to measure the spectrum of electromagnetic radiation, including visible light and radiofrequency, where we search for information such as chemical composition, temperature, density, mass, distance, luminosity, and relative motion using displacement measurements. In the case of Raman spectroscopy, we use a light diffusion process to obtain additional information about vibrations that increase the understanding of the fundamental molecular structure. These methodologies provide a diversity of data, which will be modeled and analyzed using statistical and machine learning techniques. The spectroscopy data show high dimensionality and a strong presence of outliers that cause difficulties in clustering due to false positives in discovering new clusters. For the study, a review of the literature on methods for grouping spectroscopy data that do not vary with time will be made. Thus, comparing models with the existing ones, and applying it to real data and simulated data.
Qualidade de vida, autoeficácia e autoestima de gestantes de baixo risco
(Universidade Federal de São Carlos, 2024-03-11)
Mazziero, Patricia Fernanda Evaristo
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Salim, Natália Rejane
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https://lattes.cnpq.br/1116654985699024
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https://orcid.org/0000-0001-7744-8274
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Napoleão, Anamaria Alves
Pregnancy is a period of intense changes for women, both in their body and in their lives, involving significant physical and hormonal changes. Even in low-risk pregnancies, changes are observed that can impact the quality of life of pregnant women and affect their health and that of the newborn. The way pregnant women experience these changes has repercussions on the formation of their maternity and on their relationship with their child. The self-esteem of the pregnant woman is pointed out in the literature as one of the important factors for bonding with the child, self-efficacy can favor the development of skills and contribute to coping with the alterations. Objective: To evaluate the quality of life of low-risk pregnant women and associations with self-efficacy and self-esteem. Method: This is a descriptive, cross-sectional study with a quantitative approach. It was developed in the city of Mococa-SP, in the primary care services of the municipal health network. The sample consisted of 135 pregnant women at different gestational stages. Pregnant women over 18 years of age and involved in active prenatal care were included. The study was approved by the Human Research Ethics Committee of UFSCar. All ethical principles established in CONEP Resolution No. 510 of April 7, 2016 were followed. The collection period was from July to October 2023. Results: Pregnant women had high levels of general quality of life and satisfaction with health, high levels of self-efficacy and unsatisfactory self-esteem occurred in a high percentage (81%). There was an association with quality of life and self-efficacy (p<0.005) and with sociodemographic and clinical data (p<0.05) in the physical, social relationship and environment domains. There was no association between self-esteem and self-efficacy (p=0.40). Conclusion: Pregnant women in general had adequate levels of quality of life and were satisfied with their health. They also had high self-efficacy, but decreased self-esteem. There are sociodemographic and clinical factors such as being black, having previous abortions, previous vaginal births, previous pregnancies, and having several people living in the house that were associated with certain domains for worse quality of life. The present study may contribute to clinical practice, since it points to the possibility of care focused on the specific needs of this population that go beyond the physical scope. It is suggested that new studies on quality of life, self-efficacy and self-esteem in pregnant women should be carried out, given the scarcity of studies that investigated these variables together and given the relevance of a greater understanding of the factors that influence them, which may favor the production of more robust data and contribute to the quality of care for pregnant women.
Modelos para a estimativa de propriedades elásticas em materiais compósitos sanduíche de núcleo honeycomb submetidos à flexão
(Universidade Federal de São Carlos, 2024-03-12)
Arroyo, Felipe Nascimento
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Pereira Junior, Wanderlei Malaquias
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https://lattes.cnpq.br/2268506213083114
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https://orcid.org/0000-0002-7404-3666
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Christoforo, André Luis
Due to their good mechanical performance combined with a low specific weight, sandwich composite materials have been applied in various situations, especially those with a discontinuous honeycomb core geometry, which has motivated the development of research into new materials, which naturally involves the manufacturing route and subsequent characterization. Na flexão, o conhecimento do módulo de elasticidade e da rigidez à flexão do compósito são de fundamental importância para o projeto estrutural, propriedades essas que podem ser determinadas experimentalmente ou estimadas por meio de modelos matemáticos. In the estimation of elastic properties, the ASTM D7250 (2020) standard, for reasons of design safety, disregards the core's influence in the estimation (transformed section method) of bending stiffness. With the aid of structural modeling using the finite element method and statistical analysis, the main objective of this research is to propose equations for estimating the modulus of elasticity and bending stiffness of honeycomb sandwich composites, as well as estimating bending stresses (tension and compression) under service conditions (small displacements - service limit state). After validating the modeling and parametric study (1944 simulations at three and four points, obtaining 972 different results), it was possible to develop new equations with provisions (i.e., R² greater than 0% and, in some cases, greater than 70%) better than the existing equations in the literature (i.e., R² equal to 0%).
Território, Paisagem e Fragmento: análise multiescalar das dinâmicas de supressão regular e irregular de vegetação nativa no estado de São Paulo
(Universidade Federal de São Carlos, 2024-03-12)
Gavioli, Felipe Rosafa
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Molin, Paulo Guilherme
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https://lattes.cnpq.br/1529819650942373
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https://orcid.org/0000-0002-4587-935X
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https://lattes.cnpq.br/6986957391734201
Combating illegal deforestation is a priority for society and governments, aiming to reduce greenhouse gas emissions and conserve biodiversity. Command and control actions take place in a complex manner and are carried out by environmental licensing entities within an institutional arrangement that encompasses a broad legislative apparatus for the protection of native vegetation remnants. One of the aspects of this protective apparatus is the rule established for the regular suppression of vegetation, which, however, is little studied. Knowing the characteristics of the legal suppression of native vegetation can help identify problems and propose improvements in the fiscalization and licensing ecosystem. The present study is part of this context and evaluated the dynamics of regular and irregular suppression in the state of São Paulo between 2009 and 2020, using a multi-scale approach. First, we analyze the processes of regular suppression, fiscalized irregular suppression, unfiscalized irregular suppression and regeneration of native vegetation in the territory of São Paulo, considering a municipal scale, and exploring the factors that induce these processes, using geographic data processing and multiple linear regressions. We found that legal suppression of native vegetation in the state corresponded to only 1.31% of the total suppressed between 2009 and 2020, and fiscalized suppression accounted for 11.14% of the total, meaning that 87.55% of the area of suppressed native vegetation is illegal and not fiscalized. The predominant dynamic in the state is the net regeneration of native vegetation, with 229 thousand hectares regenerated during the study period. The Cerrado presented a more worrying situation of illegal suppression, which reached around 3% of the biome's area in the state during the period studied. Regular suppression is linked to the urban-industrial development of municipalities, while unfiscalized irregular suppression is linked to the availability of road access, gentle slopes and warmer locations. The irregular suppression monitored was related to the percentage of native vegetation coverage in the municipalities and the extension of the municipalities. Then, the study focused on the regular suppressions through Authorizations for the Suppression of Native Vegetation (ASVs), analyzing the insertion of those ASVs in a landscape, considered as a radius buffer surrounding the coordinate point of the ASV. Geospatial and statistical analyzes were carried out on a landscape scale. The regular suppression of native vegetation in São Paulo is marked by small areas, of vegetation in pioneer and initial stages of regeneration, and for urban, agricultural and public works purposes. From a geographical point of view, regular suppression is concentrated in the São Paulo macro-metropolis region. Was identified an important relationship between landscape attributes and the regeneration stage of the ASV vegetation, with earlier stages occurring in more anthropic landscapes, better served by road access and with lower slopes. Based on the results obtained, improvements are suggested in government actions to combat illegal deforestation, as well as point out proposals for future studies. The results obtained can help in understanding the drivers of native vegetation suppression in the state, which contributes to the constant improvement of public forest management, management and conservation policies.