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Introdução à eletromigração controlada em materiais cerâmicos: uma revisão bibliográfica
(Universidade Federal de São Carlos, 2026-09-21)
Piazzi, Gabriel
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Motta, Maycon
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http://lattes.cnpq.br/8340540626164812
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https://orcid.org/0000-0002-5494-7705
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http://lattes.cnpq.br/7711406174484567
Electromigration became established in the early days of microelectronics as a failure mechanism in metallic interconnects, but electrically driven mass transport can also be employed to enable controlled post-fabrication modification of devices. This work presents a literature review of the historical development, physical foundations, and controlled use of electromigration, with emphasis on ceramic materials, particularly complex oxides, with a primary focus on YBa2Cu3O7−δ (YBCO). It is organized into four thematic areas: classical studies of metals, mass-flux and reliability models, fabrication and control techniques, and studies of oxygen migration in functional oxides. In metals, the discussion addresses how effective force, Joule heating, microstructure, flux divergence, and mechanical stresses lead to the formation of voids and hillocks, which are classical outcomes of electromigration. In ceramics, the analysis is extended through electrochemical potential and defect chemistry, since the displacement of ions and vacancies alters stoichiometry, oxidation states, and electronic properties. YBCO is adopted as the central case because oxygen occupancy and ordering in the CuO chains regulate hole doping in the CuO2 planes, allowing its resistance and superconducting critical temperature to be modified. The fabrication of constrictions and nanogaps, resistance- or conductance-based feedback, electropulsing, and polarity reversal are also examined as strategies for controlling electromigration. Taken together, the literature review and analyses conducted show that the same mass transport process that limits interconnect reliability can, when controlled, be employed as a nanofabrication technique for defect nanoengineering and the localized tuning of material and device properties.
Estudo computacional da estabilidade termodinâmica de complexos de nanopartículas quirais e proteínas
(Universidade Federal de São Carlos, 2026-09-22)
Bolli, Julia
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Moura, André Farias de
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http://lattes.cnpq.br/0746428641961163
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http://lattes.cnpq.br/9285996540081055
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https://orcid.org/0000-0003-4041-6433
Molecular recognition at the interface between nanoparticles (NPs) and biomolecules depends on the structural and stereochemical organization of the interacting surfaces. However, the molecular mechanisms by which surface chirality modulates protein interactions remain only partially understood. This study investigated the influence of the chirality of trimanganese tetroxide nanoparticles functionalized with mannonic acid (Mn3O4-man) on their interaction with human serum albumin (HSA). Molecular dynamics simulations were performed to investigate systems containing apo-HSA and NPs with L- and D-chiral configurations. The trajectories were analyzed in terms of interaction energies, hydrogen bonds, intermolecular contacts, and structural and conformational parameters of the protein. The results showed that the interaction with HSA strongly depends on the chiral configuration of the nanoparticle surface, as only the L-NPs were able to establish stable and energetically favorable interactions with the protein. The D-NPs exhibited only transient contacts and interaction energy profiles close to zero, without the formation of persistent bound states. Spatial analysis of the interactions revealed that chiral recognition occurred locally, with Domain III of HSA, particularly the region corresponding to the Sudlow II site, being the only region capable of sustaining a stable interface with the L-NPs, mainly involving residues Lys538, Ala539, Lys541, and Glu542. The interaction energies and contact maps suggest that interface stabilization depends on the formation of a cooperative network of spatially complementary interactions, consistent with the concept of an interfacial “chiral footprint.” Conformational analyses indicated that persistent interaction with the L-NP induces localized dynamic changes, particularly in Domain III, without compromising the overall structural stability of HSA. The RMSD, RMSF, and radius of gyration results are consistent with a two-step recognition mechanism involving initial recognition driven by stereochemical compatibility between the surfaces, followed by local conformational adaptations consistent with an induced-fit mechanism. Overall, the results demonstrate that surface chirality acts as a selective structural factor in biomolecular recognition, influencing the affinity, temporal persistence, and spatial organization of protein-nanoparticle interactions. These findings contribute to the mechanistic understanding of nano-biomolecular interactions and provide a basis for the rational design of nanomaterials with enhanced biomolecular selectivity.
Restauração florestal como processo multidimensional: variação espacial da estrutura e efeitos de traços funcionais ao longo de 17 anos
(Universidade Federal de São Carlos, 2026-09-22)
Nakasato, Marcus Vinicius
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Souza, Andrea Lúcia Teixeira de
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http://lattes.cnpq.br/5216112068627151
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https://orcid.org/0000-0002-8715-0591
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http://lattes.cnpq.br/0626499191472864
Forest restoration should be understood as a long-term process of ecological reorganization in which vegetation components and species respond at different rates to environmental changes following intervention. This thesis evaluated the development of a restoring tropical forest over 17 years around the reservoir of the Anhanguera Small Hydroelectric Power Plant in northeastern São Paulo State, Brazil. The restoration covered 70.33 ha and was established in 2008 with approximately 156,000 seedlings of 105 native tree species. The study was based on annual monitoring of 56 permanent 100 m² plots between 2008 and 2025 and, at the end of the period, comparison with 16 plots located in a local forest remnant. The thesis was based on the premise that time since planting alone does not adequately represent forest recovery because ecosystem development depends on temporal changes, spatial variation in environmental conditions, and functional differences among species. The first chapter investigated trajectories of aboveground dry tree biomass, canopy height, tree density, and vertical forest stratification. Gompertz models were used to describe and compare the trajectories of biomass, canopy height, and stratification, whereas density was analyzed directly because its dynamics were not compatible with a simple sigmoidal curve. Results showed strong asynchrony among structural components. Stratification reached its maximum rate of increase at approximately 1.2 years, followed by canopy height, with maximum growth at about 2.5 years. Biomass increased more gradually and reached its maximum increment at approximately 10.4 years. Mean biomass increased from 0.04 Mg/ha at the beginning of monitoring to 230.18 Mg/ha in year 17, accompanied by a marked increase in variation among plots. Density declined after planting because of initial mortality and later increased through the recruitment of naturally regenerating individuals, reaching 4,425 individuals/ha in 2025. At the end of monitoring, 54.9% of all individuals were recruits, although they accounted for only about 1% of total biomass, indicating that biomass accumulation remained concentrated in surviving planted trees. Spatial variation became progressively more evident during forest development, particularly for biomass. In year 17, a structural equation model showed that understory light intensity was positively associated with biomass and canopy height, whereas soil moisture was positively associated with biomass, density, and stratification. Light and moisture were negatively correlated, revealing a local environmental gradient associated with the structural organization of the forest. Because these variables were measured only at the end of the monitoring period, the relationships were interpreted as spatial associations describing the final state of the forest rather than as causal evidence for trajectories accumulated over 17 years. Comparison with the local remnant indicated partial structural convergence: stratification had reached values similar to the reference forest, but biomass corresponded to approximately 75% of that observed in the remnant, canopy height remained about 1 m lower, and density represented approximately 63% of the reference value. Thus, different attributes indicated distinct stages of recovery within the same forest. The second chapter examined whether functional traits measured at the seedling stage could anticipate differences in species performance over nearly two decades. A total of 1,161 individuals belonging to 32 tree species were followed. Specific leaf area, stem specific density, leaf and root mass fractions, and seed mass were summarized into three functional axes that explained 80.14% of total trait variation. The first axis mainly represented a gradient of biomass allocation between roots and leaves; the second was associated with stem specific density and seed mass; and the third was dominated by specific leaf area. Discrete-time hazard models were used to investigate annual mortality, and a structural equation model assessed direct and indirect effects of functional dimensions on biomass in the first and seventeenth years. At the end of monitoring, 871 individuals remained alive, corresponding to 75% of the initial cohort. Mortality risk followed a nonlinear trajectory, with a first peak between years 1 and 2, a prolonged period of lower mortality, and a second increase between years 13 and 15. Local plot biomass and the root-leaf allocation axis were not detectably associated with annual mortality risk. The axis dominated by specific leaf area was associated with a 35.4% reduction in mortality risk per unit increase, with no evidence that this relationship changed through time. In contrast, the axis related to stem specific density and seed mass showed a time-varying association: species with higher scores had greater mortality risk during part of the early and intermediate periods but lower risk during a later stage of forest development. For biomass, both the root-leaf allocation axis and the specific-leaf-area-dominated axis were positively associated with biomass in the first year. Initial biomass was the main predictor of biomass in year 17, and the specific-leaf-area-dominated axis also had a direct effect on final biomass. Therefore, differences established shortly after planting persisted for many years, but functional traits did not influence growth and mortality in the same way. Together, the two chapters demonstrate that restoration followed a multidimensional trajectory characterized by structural asynchrony, increasing spatial variation, and interspecific responses that depended on the performance component and, in some cases, on the stage of forest development. The results do not support a simple opposition between acquisitive and conservative strategies and do not allow the late increase in mortality to be attributed to a single environmental filter. From an applied perspective, restoration assessments should integrate multiple structural indicators, local environmental conditions, and complementary functional dimensions, using long-term monitoring to guide adaptive decisions. After 17 years, the forest shows a consolidated vertical structure, active natural recruitment, and substantial biomass accumulation, but it still differs from the local forest remnant and leaves open questions regarding functional replacement of planted species. Restoration therefore remains an ecological process under construction, in which growth, survival, recruitment, and functionality advance at different rates.
The music sector in the Industry 4.0 era: digital innovation solutions in the supply chain and consumer behavioral intention
(Universidade Federal de São Carlos, 2026-09-24)
Palhares, Rafael de Azevedo
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Ganga, Gilberto Miller Devós
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http://lattes.cnpq.br/9062191157466610
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https://orcid.org/0000-0001-9328-5727
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http://lattes.cnpq.br/4214557658243154
Research on Industry 4.0 in supply chains has developed mainly in traditional manufacturing and service contexts. Creative industries, however, differ substantially from these sectors in the nature of the product, the logic of value creation and market dynamics. Consequently, little is known about how these technologies are transforming the music sector. What is missing, in particular, is a systematic mapping of the technological solutions available and evidence on consumers' willingness to take part in the experiences they enable. To address this gap, this thesis investigated how Industry 4.0 technologies are transforming the Music Industry Supply Chain (MISC) and how live music consumers form the intention to participate in experiences mediated by these technologies. A mixed methods approach with an exploratory sequential design was adopted, organized into three studies. The first combined a systematic literature review, a grey literature survey, content analysis and expert validation, resulting in a framework of 37 Digital Innovation Solutions (DISs) distributed across the five MISC processes, each assigned a readiness level: 18 commercially available, 13 experimental and 6 still conceptual. Once the supply side had been mapped, the empirical investigation was delimited to the exhibition and consumption process, where the interface between technology and the consumer materializes. Within it, two formats were selected in which technology plays opposite roles: in Virtual Reality concerts, it substitutes physical co-presence with a simulated environment; in Digitally Enhanced Live Music Events (DELMEs), it retains physical co-presence and augments it through a subset of the mapped DISs. The two subsequent studies tested behavioral intention models on the same sample of 1,242 Brazilian consumers, analyzed through partial least squares structural equation modeling. The second integrated the Unified Theory of Acceptance and Use of Technology with the Diffusion of Innovations theory to explain the intention to attend Virtual Reality concerts, incorporating three original constructs: immersive experiential value, physical discomfort risk and perceived rapid adaptability. The third integrated the same acceptance theory with the Theory of Consumption Values to explain participation in DELMEs, specifying instrumental value as a formative construct and proposing multisensory experiential value. The models, specified according to the nature of each format, explained 58.9% and 70.7% of the variance in intention. In both, the strongest predictors were social and experiential rather than technical: in virtual concerts, social influence and immersive experiential value, with facilitating conditions acting indirectly through perceived rapid adaptability; in DELMEs, instrumental value and multisensory experiential value, with technological feasibility operating as an enabling condition. Relative advantage was not supported, suggesting that the two formats constitute distinct modes of music consumption, more complementary than substitutive.
A anatomia da mentira: uma análise semântico-pragmática
(Universidade Federal de São Carlos, 2026-09-25)
Colosso, Carolina Peternela
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Basso, Renato Miguel
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http://lattes.cnpq.br/6984826176670527
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https://orcid.org/0000-0003-2580-0365
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http://lattes.cnpq.br/6468140086178773
Lying is a complex phenomenon, present in various situations of human interaction and traditionally associated with the utterance of a false statement with the intention of deceiving the interlocutor. However, the diversity of communicative situations in which lying may occur highlights the difficulties in defining it on the basis of strict and necessary criteria. In this context, this dissertation aims to investigate the notion of lying in Brazilian Portuguese (BP) from a perspective grounded in the philosophy of language and Prototype Theory, seeking to understand its gradual organisation and to identify the relevance of the elements that contribute to its categorisation. The research takes as its starting point the model proposed by Coleman and Kay (1981), according to which the prototypical lie involves three features: (A) factual falsity of the proposition, (B) intention to speak falsely, and (C) intention to deceive. Methodologically, the study revisits and expands on previous experiments conducted with speakers of Brazilian Portuguese (Colosso, 2024), through the use of different questionnaires comprising stories representing the possible combinations of the three features. Participants rated each situation on judgement scales, enabling the observation of different degrees of lie attribution and a comparison of the organisation of the features across different experimental conditions. The results show that the simultaneous presence of all three traits constitutes the prototypical core of the category, associated with the highest ratings and the greatest consensus amongst participants. The intermediate conditions, in turn, show that the traits carry different weights in the categorisation: the intention to speak falsely (B) proved to be the most relevant element, followed by the intention to deceive (C), whilst the factual falsity of the proposition (A) had the least influence on the judgements. A comparison with previous findings also reveals a reorganisation in the hierarchy of features, indicating that the categorisation of lies in Brazilian Portuguese does not depend exclusively on the correspondence between the proposition and reality, but primarily involves aspects related to the speaker’s intentions and mental states. It is concluded that, in Brazilian Portuguese, lying does not constitute a category rigidly defined by necessary and sufficient conditions, but rather a gradual category, organised around a prototype and peripheral cases. The results thus reinforce the relevance of the prototypical approach to the study of lying and contribute to an understanding of the interface between Semantics, Pragmatics and Cognition.
Silicato de prata sintetizado por micro-ondas: correlação entre estrutura, propriedades eletrônicas e atividade biológica
(Universidade Federal de São Carlos, 2026-09-25)
Doimo, Ana Luiza de Camargo
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Assis, Marcelo de
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http://lattes.cnpq.br/3449316915846364
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https://orcid.org/0000-0003-0355-5565
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Silva, Elson Longo da
MICROWAVE-SYNTHESIZED SILVER SILICATE: CORRELATION BETWEEN STRUCTURE, ELECTRONIC PROPERTIES, AND BIOLOGICAL ACTIVITY. Infectious diseases and the increasing resistance of microorganisms to antimicrobial treatments remain among the major challenges to global public health. The COVID-19 pandemic highlighted the vulnerability of healthcare systems to emerging pathogens, reinforcing the need for new strategies for the prevention and control of infectious diseases. Within this context, nanomaterials and, particularly, silver-based semiconductors have attracted considerable attention due to their broad antimicrobial activity and their potential to act through multiple mechanisms, such as the generation of reactive oxygen species and disruption of cell membranes. In this context, silver silicate stands out as a promising material for antimicrobial applications due to its physicochemical properties and potential for reactive oxygen species generation. In this work, silver silicate was synthesized by coprecipitation followed by microwave-assisted hydrothermal treatment, with irradiation times ranging from 0 to 64 min. Although all samples exhibited an amorphous character by X-ray diffraction, spectroscopic and electron diffraction analyses revealed progressive changes in structural organization and the development of semicrystalline regions with increasing synthesis time. Microscopic analyses showed a reduction in particle size associated with dissolution and recrystallization dynamics during microwave irradiation. Elemental analyses revealed a progressive increase in silver incorporation. The antimicrobial activity of the materials increased with synthesis time, with the sample obtained after 64 min exhibiting the highest performance against Staphylococcus aureus, Escherichia coli, and Candida albicans. The effective concentrations against these microorganisms remained below the toxicity levels observed in NIH/3T3 fibroblasts. The generation of reactive oxygen species was experimentally confirmed and increased with irradiation time. Therefore, microwave-assisted synthesis proved to be an effective strategy for controlling the structure, composition, and defects of silver silicate, resulting in a material with high antimicrobial activity and favorable biological compatibility.
“O Tempo e a Constância”: reflexão sobre uma trajetória acadêmica na medicina
(Universidade Federal de São Carlos, 2026-09-30)
Zanatta, Ricardo Patrezi
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Ferreira, Esther Angélica Luiz
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http://lattes.cnpq.br/4054544728456101
This work is a reflective portfolio documenting the author's journey through the Medicine program at the Federal University of São Carlos (UFSCar), aiming to answer the question: "Did I manage to contribute to the UFSCar Medicine program being in a better state when I left than when I started?" The introduction outlines a career choice born not of an early calling, but of curiosity and gradual discovery, following the decision to abandon plans to pursue other fields of study. Upon admission, the ambition to leave the UFSCar program at a higher level than he found it became the guiding principle of his university experience. The results describe—in descending order of time commitment—the author's main areas of involvement: the Athletic Association (*Atlética*), where he held various roles over six years, developing skills in organization, leadership, communication, and problem-solving; over 20 extension projects, viewed as a way to give back to society for the investment received; four undergraduate research projects, collaborations on other studies, and conference presentations, resulting in two awards; a research internship in Toledo, Spain, in 2024—the fulfillment of a long-held dream; and elective internships, which marked the transition from curiosity to professional practice. The text also highlights human capital—comprising faculty, staff, and students—as UFSCar’s greatest asset, acknowledging the individuals who shaped the author's education. The discussion reveals that non-technical skills, teamwork, and giving back to the university are central elements of medical training. The conclusion notes that it is impossible to state definitively whether the goal of elevating the program's standing was actually achieved; that assessment will be left to time and future generations. However, the author concludes his undergraduate studies satisfied with the effort dedicated to this endeavor and grateful for the relationships built.
Produção de mudas cítricas e perspectivas para citricultura brasileira
(Universidade Federal de São Carlos, 2026-12-01)
Oliveira, Mateus Borges de
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Conceição, Patrícia Marluci da
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https://lattes.cnpq.br/6623193710607120
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https://orcid.org/0000-0002-9966-3191
The citrus industry is one of the main activities of Brazilian agribusiness, playing an essential role in generating income, employment, and foreign exchange for the country. This study aimed to analyze the technical and legal aspects involved in the production of citrus nursery plants, as well as to discuss the perspectives and challenges of the Brazilian citrus sector, in order to inform production practices that ensure phytosanitary quality and sector sustainability. Through an integrative literature review, information was gathered from scientific publications, legislation, and technical reports issued by institutions such as MAPA, Embrapa, and Fundecitrus. It was observed that the mandatory use of screened nurseries for citrus seedling production initially established in the state of São Paulo and later extended Nationwide represented a milestone in the modernization of the sector, reducing the spread of diseases such as Citrus Variegated Chlorosis (CVC) and huanglongbing (HLB). The importance of using certified mother plants, implementing sanitary indexing, and applying improved grafting techniques and protected-environment management was also verified. The adoption of rootstocks such as citrandarins and Swingle citrumelo has contributed to greater disease resistance and better adaptation to different edaphoclimatic conditions. Furthermore, the expansion of citrus cultivation into new regions such as Goiás, Mato Grosso do Sul, Bahia, and Paraná reflects not only the search for areas with lower HLB incidence but also economic and structural factors that influence the productive reorganization of the sector. It is concluded that the integration of technology, legislation, and sustainable management is fundamental to ensuring seedling health, competitiveness, and the long-term sustainability of the Brazilian citrus industry.
Análise genética de vacas em relação à sua idade no último parto através de modelos de sobrevivência
(Universidade Federal de São Carlos, 2026-12-03)
Afonso, Eduarda Godoy
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Caetano, Sabrina Luzia
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https://lattes.cnpq.br/2340330162391128
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Zuanetti, Daiane Aparecida
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https://lattes.cnpq.br/8352484284929824
In Brazil, the study of bovine longevity is extremely important due to the country’s position in the export and production of this sector and, for this reason, there is a strong interest in achieving maximum profitability in this activity. The economic longevity of cows is totally related to reproductive performance, with the trait known as the age of the cow at last calving (ACLC) being a very important variable in this context. Since this variable cannot always be perfectly measured in some scenarios, a censoring criterion is generally applied to this characteristic, which is based on the difference between the date of the cow’s last observed calving and the date of the last calving on the farm. If this difference is greater than or equal to 36 months, the cow failed, as she has gone too long without calving and will be discarded. Otherwise, the cow is still considered reproductive and her age at last calving is censored, since there is still a possibility of her having another pregnancy. Therefore, one of the objectives of this study is to genetically analyze the IVUP variable using frailty models applied to survival analysis. The use of this type of model is justified by the inclusion of random effects, allowing the prediction of genetic factors associated with each animal and also considering associations between them. Another objective of the study is to identify genetic variables that influence bovine longevity, and this will be done through a Genome-Wide Association Study (GWAS). The analysis is done using a sample of 862 cows, daughters of 47 different bulls. For confidentiality reasons, the origin of the data is kept secret.