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Desenvolvimento de novos aços inoxidáveis lean - propriedades mecânicas e tribológicas
(Universidade Federal de São Carlos, 2024-04-24) Silva, Rinara Gregório; Labiapari, Willian da Silva; Koga, Guilherme Yuuki; https://lattes.cnpq.br/0933095081175012; https://orcid.org/0000-0003-0792-1139; https://lattes.cnpq.br/2968058733983946; https://orcid.org/0009-0006-8016-4049; Gargarella, Piter; Wolf, Witor; https://lattes.cnpq.br/9656544805116765; https://lattes.cnpq.br/4641435644243916; https://orcid.org/0000-0003-4445-5819
Carbon steels are attractive materials given their low cost and satisfactory mechanical strength for various engineering applications. The low price of carbon steel is ascribed to the reduced content of alloying elements, such as Cr, but with the expense of the corrosion resistance. Stainless steels, in turn, combine high mechanical and corrosion resistances, this latter assured by the higher Cr levels, normally above 10.5 wt%. A large compositional region of steels containing Cr in the range between 6 and 11 wt% is still little explored. These Cr-lean steels promise as competitive alternatives for applications in presence of aqueous medium, whose aggressiveness is low for traditional stainless steels, but high for carbon steels. Thus, this project aims to produce and to evaluate the mechanical and wear resistances of steels with low carbon content (< 200 ppm) and chromium varying between 6 and 11%. The steels were produced in a vacuum induction furnace at the Materials Engineering Department at UFSCar and rolled, annealed, and pickled at Aperam, in Timóteo – MG. The alloys were characterized in terms of chemical composition, microstructure and mechanical properties in tensile tests. Wear resistance under annealed and tempered conditions was assessed through the microsclerometry and dry sand in a rubber wheel. The results showed that the mechanical strength increases with the increase of the chromium content for the annealed condition. On the other hand, in the quenched condition similar properties for all alloys was observed regardless of the Cr content, ~1GPa of tensile strength and a hardness of ~270 HV. The abrasive wear tests showed that the quenched condition has higher resistance, and the predominant wear mechanism was micro-grooving. From this work results we conclude that the martensitic microstructure is not so fragile, it is strong, hard, more resistant to abrasive wear and we can remove the chromium while maintaining the same mechanical strength level for lean alloys.
Função vascular e autonômica cardíaca em indivíduos hospitalizados com diagnóstico de exacerbação da doença pulmonar obstrutiva crônica, insuficiência cardíaca ou coexistência das doenças e investigação do efeito agudo vascular da ventilação não-invasiva em doentes com insuficiência cardíaca
(Universidade Federal de São Carlos, 2024-04-24) Schafauser, Nathany Souza; Sampaio, Luciana Maria Malosa; https://lattes.cnpq.br/2970138065407046; https://orcid.org/0000-0002-0110-7710; Mendes, Renata Gonçalves; https://lattes.cnpq.br/9634590922242052; https://orcid.org/0000-0003-4683-2657; https://lattes.cnpq.br/5075933151971198; https://orcid.org/0000-0002-7790-7191
Chronic Obstructive Pulmonary Disease (COPD) and Heart Failure (HF) often coexist in the same individual and independently are associated with systemic inflammation and increased cardiovascular risk, with a worse prognosis when combined. During COPD exacerbations (ECOPD), there is an aggravation of inflammation, oxidative stress, and endothelial dysfunction, contributing to increased vulnerability to cardiovascular complications. Similarly, decompensation of HF is marked by acute deterioration of the clinical condition with intensification of signs and symptoms of pulmonary and/or systemic congestion, associated or not with worsening tissue perfusion. During periods of greater stability, evidence points to impairment in aspects such as arterial stiffness, endothelial function, and cardiac autonomic modulation (CAM) in both diseases, but there is still a gap regarding this more comprehensive cardiovascular approach during exacerbation and hospitalization, as well as the influence of HF comorbidity during ECOPD. Additionally, the use of non-invasive ventilation is indicated in the treatment of decompensated HF (DHF). NIV in patients with HF has been shown to improve ventricular function, increase intrathoracic pressure, and cardiac output. However, it is still unknown whether these hemodynamic improvements translate into improved endothelial function. STUDY 1 - OBJECTIVE: To investigate the cardiovascular profile of hospitalized patients with ECOPD in the presence of HF and compare it with isolated forms of COPD and HF. METHODS: Cross-sectional study including patients diagnosed with ECOPD and decompensated HF (DHF), divided into 3 groups: COPD, COPD-HF, HF. evaluated between 24 and 48 hours after hospital admission. The comprehensive cardiovascular assessment included: 1. Endothelial function: flow-mediated dilation (FMD) methods; 2. Arterial stiffness and hemodynamic variables by pulse wave analysis and carotid-femoral pulse wave velocity (cfPWV); and 3. CAM by heart rate variability analysis. RESULTS: Patients were allocated to groups according to diagnosis as follows: COPD, n = 12; COPD-HF, n = 21; HF, n = 21. In our sample, the mean FMD was 4.45%, indicating endothelial dysfunction. However, in the group with both diseases coexisting, a worse FMD (%) was observed, as presented sequentially for COPD, COPD-HF, and HF. FMD: 5.47 (3.96 – 6.91); 2.66 (0.09 – 3.48); 4.60 (2.30 – 6.43) in % p<0.0005). Augmentation Index (AIx: 29 (19 – 42.6); 34.6 (24.3 – 43.25); 14.5 (8 – 24) p<0.007; cfPWV: (6.5 (5.4 – 7.2); 7.7 (7.0 – 8.5); 6.05 (5.02 – 6.52) in m/s); The COPD-HF group showed greater sympathetic modulation compared to isolated diseases (SNP: -1.32 (-2.53 – -0.62); -2.33 (-2.60 – -2.12); -1.32 (-1.42 – -1.01) p<0.006; SNS: 3.5 (1.40 – 8.55); 7.11 (5.70 – 8.29); 2.32 (1.78 – 5.01) p<0.009). Other indices rMSSD, NN50, pNN50, and TINN also indicate worse CAM in the ECOPD-HF group compared to isolated COPD and HF. CONCLUSION: Vascular function and CAM are more impaired in patients with the comorbidity of HF present in COPD compared to isolated forms of HF and COPD. STUDY II - OBJECTIVE: To investigate the acute effect of NIV on endothelial function in patients hospitalized for DHF. METHODS: Quasi-experimental study including n=20 patients diagnosed with ADHF approached between 24 and 48 hours after hospital admission. The application of NIV lasted between 30 and 60 minutes, using inspiratory pressure between 8 and 12 cmH2O and expiratory pressure between 5 and 7 cmH2O, according to patient tolerance. Before NIV, the following assessments were performed: (1) complete blood count, C-reactive protein, N-terminal pro-B-type natriuretic peptide, and arterial blood gas analysis; and (2) endothelial function, using ultrasound of the brachial artery by the flow-mediated dilation method. Immediately after NIV, the assessments were repeated. The analysis considered the response of flow-mediated dilation after NIV (Δ FMD = FMDpost - FMDpre) and compared the subgroups according to the response in non-responders (ΔFMD < 1.79%) vs. responders (ΔFMD > 1.79%). RESULTS: After NIV, an increase in FMD was observed (4.27 ± 2.51% vs. 6.01 ± 2.80%, P < 0.001), with no significant change in arterial blood gas (p>0.05). In the comparison of non-responders versus responders’ subgroups, patients with lower endothelial response after NIV (ΔFMD < 1.79%) showed higher levels of eosinophils (222 ± 74.8 mm3 vs. 101 ± 24 mm3; p=0.002) and C-reactive protein (7.7 ± 10.17 mg/dl vs. 1.94 ± 2.13 mg/dl; p = 0.021). CONCLUSION: The application of NIV acutely improves endothelial function in patients with DHF. The acute unresponsive effect of NIV on endothelial function in patients with DHF may reflect a negative influence of inflammatory markers.
(Des)controle do imaginário: o regime militar como lastro das ficções de Micheliny Verunschk e Joca Reiners Terron
(Universidade Federal de São Carlos, 2024-04-24) Oliveira, Julia de Mello Silva; Rocha, Rejane Cristina; https://lattes.cnpq.br/5669300635333699; https://orcid.org/0000-0002-5944-6846; https://lattes.cnpq.br/0358215216384521; https://orcid.org/0000-0001-8434-2355
Since the beginning of this second millennium, we have been favoring the improvement of the data-driven way of living. In this improvement, the market is increasingly establishing its logic of speculation and prospecting of demands and agendas by using socially circulating discourses. Through this mechanism, the market can offer to the customers products that fit in their interests until we reach the current peak of the datasphere (BEIGUELMAN, 2021). From the beginning of such improvement until this very moment in which we consolidate it, information is the great driver of profit. The publishing market, which functions as a discursive institution (SALGADO, 2016), utilizes the media-algorithmic rules to speculate and explore the agendas and demands socially in circulation and incorporates them as a basis for the publication, circulation, and sale of books. Indeed, the author is also a result of his time and has a position in this dynamic as a catalyst and prism of culture that appears filtered in his written products. To be published and to the publication have some impact, however, it is necessary to take part in the publishing market dynamics. This is the logic that definitely determines the themes and forms of literature since we began to assume information as an organizational vector of Western thought. In Brazil, we have seen, little by little, a progressive political process that reflects ideologies centralizing issues of equality and social justice. When we had a president who was a former activist against the military dictatorship of 1964 (which coincides with the work of the National Truth Commission and the 50th anniversary of the regime) we were experiencing the peak of information, discourses, and social demands for an inclusive, fair, and diverse democracy, capable of looking at its past, present and future with that very lens. Groups in favor of this ideology and against it are equivalent to groups in favor of historical reparations regarding the various authoritarianism agendas we have experienced since colonization and groups that do not think this should be a value in managing the country's politics. Regardless of the pole - in favor or against it -, the debate was set, and polarized information was in circulation, generating demands to be met by the market and the publishing market. The coincidence between “being in favor of the dictatorship” and “being against such values as guides for State management” or between “being against the dictatorship” and “being in favor of a specific social democracy” had consequences for literature, especially in one of its niches: the 1964 dictatorship literature. In fact, due to the context introduced, this literary segment presented a politicized and referentialized literary representation (which is positive in the sense that literature could be an equalizer of political debate). On the other side, nonetheless, the fiction work was marginalized. This scene - more referentialization, less fiction - made the boom in Brazilian contemporary post-dictatorial novel. This kind of literature has been published since the 2000s and centralizes the 1964 dictatorship in its plot. It also has a tentacular narrative that materializes the aesthetics of insurgency to be put in the form of a literary product (ZOHAR, 2017) which will be neutralized by the need for profit, the end of the entire marketing process. Our work, based on the Theory of Imaginary Control by Luiz Costa Lima (2007; 2009), describes this phenomenon and proves the hypothesis that Noite dentro da noite by Joca Reiners Terron, and Trilogia Infernal, by Micheliny Verunschk, escape such description.
Coexistência e conflitos humano-fauna: percepções da comunidade do Parque Estadual do Jaraguá (SP, São Paulo)
(Universidade Federal de São Carlos, 2024-04-24) Thomaz, Clarice; Silva, Rosana Louro Ferreira; https://lattes.cnpq.br/2635824351245453; https://orcid.org/0000-0002-5787-2331; https://lattes.cnpq.br/9137687470091897; https://orcid.org/0009-0008-3005-9819
Human-wildlife relations can be characterized as interactions that can generate positive or negative impacts on wildlife, people, or both. When positive impacts reach both sides of the interaction, cohabitation is established. However, given the complex reality of human relations with wildlife, coexistence is not always achievable. When negative impacts affect both, human-wildlife conflict arises. These conflicts can be managed by seeking to improve the relationship between people and animals, significantly reducing negative impacts, and striving to establish coexistence. In this sense, environmental education can make important contributions by fostering an alignment between concepts, values, and forms of participation on the subject. This investigation aimed to understand elements indicating the community's perspective (staff and visitors) regarding conflicts and coexistence in Jaraguá State Park. To achieve this, we used data from semi-structured interviews, a mixed questionnaire, and Walking Ethnography. We also analyzed conflicts in the region based on wildlife incidents data provided by an institution that assists wildlife in the municipality. The results reveal conflicts primarily related to feeding animals in the Park and the presence of domestic animals in the area. Several actions, mainly educational, were identified as contributing to conflict management toward coexistence. Wildlife incident data align with the community's perception, indicating primates as one of the groups most involved in incidents, especially marmosets and capuchin monkeys. We understand the need for this management to be collaborative and dialogical, considering the participation of the entire community. At the end of the process and based on our results, we aimed to indicate preferred formats and themes for future production of educational materials contextualized to the area.
Autogestão da dor crônica no processo de retorno ao trabalho: vivência de trabalhadores
(Universidade Federal de São Carlos, 2024-04-24) João, Rosilene de Oliveira Rosa; Hortense, Priscilla; https://lattes.cnpq.br/7153278628783234; https://orcid.org/0000-0003-0554-451X; Mininel, Vivian Aline; https://lattes.cnpq.br/4557060516800427; https://orcid.org/0000-0001-9985-5575; https://lattes.cnpq.br/8075018464038248; https://orcid.org/0009-0005-6754-9318
Introduction: chronic pain has a high prevalence in Brazil and around the world, and exerts significant impact on people’s lives, including the professional and social relationships dimensions. Strategies that promote self-management of pain and maintenance of work activities are useful for health professionals, managers and people with pain themselves, and should be investigated. Objective: to understand the chronic pain self-management strategies used by workers in the process of returning to work. Method: the study design included two stages. The first was a literature review aimed at identifying and synthesizing pain self-management strategies guided by PRISMA recommendations, conducted in the MEDLINE, WoS and Scopus databases, including studies published in Portuguese and English between 2017 and 2022, based on the descriptors “chronic pain” and “return to work”. In the second stage, a field study focusing on understanding the experiences of workers with chronic pain regarding their return to work was developed at the Health School Unit of the Federal University of São Carlos with the target audience: workers over 18 years old, regardless of sex, type of employment or occupation, undergoing rehabilitation care at the unit, with chronic pain for at least three months and who had returned to work after any period of absence. Data were collected through individual interviews guided by semi-structured questions and analyzed using thematic content analysis. Results: in the review, of the 14 studies included, ten indicate strategies for self-management of chronic pain predominantly focused on the individual through multidisciplinary programs, two have the participation of the work supervisor in the process, and two describe actions in the work environment as facilitators for returning to work. The results highlighted organizational weaknesses regarding support strategies and adaptations in the work environment. Participants in the field study were 12 workers, six of which were informal and/or self-employed, predominantly female and diagnosed with fibromyalgia. The analysis resulted in 27 recording units and the following thematic categories: aspects that contributed to pain; repercussions of pain on life and work; pain self-management strategies; facilitators and obstacles to returning to work. The results pointed to environmental and organizational aspects of work as contributing to the emergence or worsening of pain and among pain self-management strategies for returning to work, most were individual-focused and had little involvement of the organization in this process. Conclusion: in view of the pain self-management strategies brought by participants of this study, and the significant eases and difficulties in returning to work, the following are emphasized; individual focus, the absence of programs aimed at returning and maintaining work, lack of involvement of employers in sharing this responsibility, the need for adaptations in the workplace, as well as the lack of preparation of health professionals, in general, to care for workers with chronic pain.
Mineração de texto, inteligência artificial e aplicações em biotecnologia
(Universidade Federal de São Carlos, 2024-04-24) Reis, Vítor Eulálio; Caracelli, Ignez; https://lattes.cnpq.br/8956527354576143; https://orcid.org/0000-0003-4945-7485; Pataxo; https://lattes.cnpq.br/2456364381525767; https://orcid.org/0009-0000-0314-8869
Large Language Models (LLMs) are AI-powered programs that generate and manipulate text, learning to understand and respond in a human-like way by developing their descriptive capabilities and potential. LLMs face challenges such as specific knowledge gaps, factuality issues, and hallucinations. Therefore, Retrieval-Augmented Generation (RAG) aims to address these challenges by connecting models to external and verified knowledge sources. In this context, the RAG approach is used here to analyze and extract responses from scientific texts, investigating the intrinsic relationship within the complex connections and the relationship with current use. The methods and techniques are based on AI for different language processing to retrieve, rationalize, and mobilize the knowledge present in an interdisciplinary technical-scientific knowledge to be validated. Therefore, techniques for text mining generated from relevant documents are integrated, while text generation seems to operate more effectively in complex contexts for specific in-depth analysis. Additionally, the field of Science or Science-Bot studies potential connections and interactions that are imagined or underrepresented in the literature, contributing to the ongoing debate in various ways. As a case study, Sci-Bot was fed scientific texts with existing information on possible directions for future research, public health strategies in the area control and prevention, and even in changing cultural traits. Thus, the RAG approach makes it possible to articulate textual information from the scientific literature, enabling a detailed explanation on an unprecedented scale of all the complex connections or intersections between the key concepts involved in the recent context of the pandemic.
Efeito de diferentes estratégias de fresamento sobre a qualidade de superfícies especulares em aços ferramenta
(Universidade Federal de São Carlos, 2024-04-24) Castanheira, Lucas Cappucio; Xavier, Fábio Antonio; https://lattes.cnpq.br/5972471462669372; Ventura, Carlos Eiji Hirata; https://lattes.cnpq.br/1689198421096127; https://lattes.cnpq.br/4592329983794114
The importance of the plastics industry and the use of this type of material for the most diverse purposes to the development of steel alloys for the manufacturing of injection molds. Mold manufacturing has a direct influence on product delivery time, costs, and quality, and milling is one of the most relevant processes for its production. Given the difficulty in machining hardened steels and the geometries commonly observed in injection molds, besides the necessary surface quality to generate plastic parts without defects, an adequate milling strategy must be chosen, which implies in defining not only the cutting parameters and the tool, but also its trajectory. Thus, the present work focuses on investigating the influence of two different cutting strategies in milling process on the surface quality of convex (constant curvature) surfaces on two types of material. The quality will be evaluated from the different roughness parameters correlated to the quality of the perceived gloss and will be evaluated and be correlated to the characteristics of each material, such as hardness and microstructure. After the tests, in the finishing step it was possible to verify the positive influence of the parallel strategy obtaining the lowest values of average roughness Sa and maximum Sz in both steel alloys VH13IM and VTMPlus in comparison with the zig-zag strategy. Those results were congruent with the generated images from the machined surfaces by the finishing step. The combination of low roughness values with a homogeneous topographic profile of the surface led to a higher brightness and mirror finish.
Equações elípticas com o Laplaciano fracionário e não linearidades indefinidas
(Universidade Federal de São Carlos, 2024-04-24) Gobbi, Ray Santos; Miyagaki, Olimpio Hiroshi; https://lattes.cnpq.br/2646698407526867; https://orcid.org/0000-0002-5608-3760; Paiva, Francisco Odair Vieira de; https://lattes.cnpq.br/2889322093175193; https://orcid.org/0000-0002-6852-4279; https://lattes.cnpq.br/1493756092018784; https://orcid.org/0009-0005-1704-4071
In this work, we investigate the existence, non-existence and multiplicity of positive solutions of the problem below, \begin{equation*}\left\lbrace \begin{array}{rll} (-\Delta)^s u -\lambda u & = f(x)g(u) ,& \textrm{em } Omega\\u & = 0 &\textrm{sobre } \partial \Omega\end{array} light.end{equation*} where $\Omega$ is a bounded smooth domain of $\R^N$, $f$ is a continuous and bounded function that changes sign in $\Omega$, and $g$ is a real function and can be subcritical or critical. The operator $(-\Delta)^s$ is the Fractional Laplacian, $N \geq 2s$, $s \in (0,1)$ e $\lambda \geq \lambda_1$, where $\lambda_1$ is the first eigenvalue of operator $(-\Delta)^s$. Ours results will be obtained through variational sub-super solution methods, mountain pass theorem and linking theorem.
Hops: agroclimatic zoning and favorability for the occurrence of Downy Mildew for the state of Santa Catarina, Brazil
(Universidade Federal de São Carlos, 2024-04-24) Arruda, Marcia Magalhães de; Santos, Alexandre Rosa dos; https://lattes.cnpq.br/7125826645310758; https://orcid.org/0000-0003-2617-9451; Jesus Junior, Waldir Cintra de; https://lattes.cnpq.br/2614953467362376; https://orcid.org/0000-0001-5711-0268; https://lattes.cnpq.br/2502052957759675; https://orcid.org/0000-0003-3964-4818
Hops (Humulus lupulus) is a herbaceous species with significant economic value, primarily used as a fundamental ingredient in the brewing industry, providing bitterness, aroma, and stability to beer. However, its cultivation faces significant challenges, among them downy mildew, a disease caused by the pathogen Pseudoperonospora humuli. To gain a better understanding of this pathogen, we conducted a systematic literature review, employing bibliometric techniques to analyze existing knowledge on the subject. We identified 54 publications focusing on the efficacy and resistance of downy mildew management in hops, as well as the genetic and pathogenic relationships. The analysis also highlighted themes such as disease management, cultivar susceptibility, and the influence of climate on the development of downy mildew. Regarding hop cultivation in Santa Catarina, Brazil, an agroclimatic zoning was carried out using conventional approaches and Fuzzy logic. Based on the results, it was found that the mountainous and southern regions of the state are more favorable for hop cultivation, while areas such as the extreme north and coastal regions present restrictions due to unfavorable climatic conditions. The zoning through the reclassification of variables for downy mildew incidence identified 63.13% of the area of Santa Catarina as favorable for the disease, while the Pseudoperonospora humuli approach indicated a proportion of 92.80%. It was concluded that the combination of these techniques provides a comprehensive view of the favorable climatic conditions for hop cultivation and downy mildew occurrence, highlighting the importance of management and the development of resistant varieties for hop cultivation in Santa Catarina.
Efeitos do ensino sequencial e simultâneo de duas línguas estrangeiras na aquisição de um pequeno vocabulário em crianças
(Universidade Federal de São Carlos, 2024-04-24) Cunha, Mariana Farias da; Cortez, Mariéle Diniz; https://lattes.cnpq.br/7927746584626515; https://orcid.org/0000-0003-3301-8330; https://lattes.cnpq.br/5434810112127377; https://orcid.org/0000-0001-7456-5168; Miguel, Caio Flávio Andriussi; Ribeiro, Daniela Mendonça; https://lattes.cnpq.br/9137388590869969; https://orcid.org/0000-0002-5624-6718; https://orcid.org/0000-0003-4146-5122
The present study investigated the effect of tact instruction (naming pictures) in two foreign languages (English and Spanish), conducted sequentially or simultaneously, on the emergence of bidirectional intraverbal responses (translation) between the two foreign languages (FL1 and FL2) and the native language (NL). Study 1 examined the effect of this instruction when conducted sequentially. Six children participated, three exposed to the FL1-FL2 sequence and three to the FL2-FL1 sequence. All participants were subjected to the following experimental conditions in a multiple baseline design: 1) Intraverbal Response Test (Pre-Instruction), which assessed bidirectional intraverbal responses (FL1-NL; NL-FL1; FL2-NL; NL-FL2; FL1-FL2; FL2-FL1); 2) Tact Test (pre-instruction), which assessed tact responses in the two foreign languages before exposure to the teaching condition; 3) Tact instruction, in which the experimenter presented each stimulus simultaneously with the question "What is this in English?" or "What is this in Spanish?" and then provided echoic prompts using progressive delay (0s; 2s; 4s) and provided differential reinforcement for responses; 4) Probes and Post-Instruction, which assessed the emergence of the six intraverbal relations tested after tact instruction; and 5) Maintenance, which assessed, after 30 days, the maintenance of directly taught tact relations and the six emerging intraverbal relations. In Study 1, there was no effect on the order of language instruction, but a learning set effect was observed in both orders, with high levels of emergence after instruction and during maintenance of taught and emerging relations. Study 2 aimed to investigate the effect of simultaneous tact instruction. Three children participated and were subjected to an adapted alternating treatment design and the same experimental conditions as Study 1. In Study 2, no differences were found in the amount of blocks for FL1 and FL2, and there were also varied levels of maintenance. Both studies were effective in producing emergence of bidirectional intraverbal relations, confirming results from previous studies. In both studies, participants demonstrated greater ease in responding in the native language and encountered more difficulties in relations between the foreign languages. Comparison between the studies should be done cautiously, as there was a relaxation of learning and emergence criteria for Study 2.