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Ensino de ciências e mudanças tecnológicas: do dilema limitante à construção humanizadora no IF Baiano campus Santa Inês
(Universidade Federal de São Carlos, 2025-05-27) Silva, Cleber de Souza; Pierson, Alice Helena Campos; https://lattes.cnpq.br/3749421379531019; https://orcid.org/0000-0002-5418-3418; https://lattes.cnpq.br/6820414738853018; https://orcid.org/0009-0001-4184-6470
The contradictory role made to technology in modern times, of satisfying human needs while simultaneously being a means of reproducing oppression/exclusion, contrasts with the representation of the neutral and evolutiove application of scientific knowledge still present in Brazilian schooling. By defending the humanizing relationship, we seek to answer the question: what are the relationships between science teaching at IF Baiano, Santa Inês campus, and the technological changes in the living space of this community, established by subjects of scientific and technological education? We highlight the scientificist-technicist dilemma as a discursive practice organizing science teaching at the institution, and we discuss its historical roots. The dialogue between the studies of Dussel (1984), Feenberg (2010), and Santos (2002) included decisive elements in reaffirming the importance of a rupture in the meanings of technology shared by the subjects of education. We designed and carried out an ethical-critical curricular exercise based on the principles and guidelines of Freirean Thematic Investigation, the Curricular Restructuring Movements, and Critical Collaborative Research. In the thematic network produced, we observed the feasibility of the humanizing relationship between science teaching and local/global technological changes. Despite the regionalized limit situations, namely, the naturalization of productivism, clientelism and discrimination, bringing together significant statements that articulate the technological dimension, there was no consensus among educators about the contributions of science teaching. Finally, we highlight changes in ethics admitted by the collaborative research group, from an initial consensus to a conflict of positions about the best curricular orientation for science teaching.
Improved parallel algorithm for finding minimum cuts in stochastic flow networks
(Universidade Federal de São Carlos, 2025-05-27) Joshan, Mohammad Sadegh; Pedrino, Emerson Carlos; https://lattes.cnpq.br/6481363465527189; https://orcid.org/0000-0003-3734-3202; https://lattes.cnpq.br/0277215938197917; https://orcid.org/0009-0000-5164-3346
The expansion of information in social networks, bioinformatics, and transportation has resulted in the emergence of enormous graphs with millions or even billions of nodes and edges. Examples include communication networks with stochastic bandwidth, traffic systems with probabilistic congestion, and power grids with uncertain load demand. These scenarios pose unique computational challenges due to their probabilistic nature and dynamic structure. Traditional sequential techniques for identifying minimum cuts in graphs are ineffective in this context, as their time complexity becomes excessively high. This thesis addresses the problem by employing parallel techniques to compute minimum cuts more efficiently on large-scale graphs, leveraging modern parallel computing resources without compromising accuracy. The initial investigation explores state-of-the-art algorithms such as Parallel Push-Relabel and Parallel Karger, which depend on specific hardware and software conditions. The results support the design of the Dynamic Parallel Graph Cuts Algorithm (DPGCA), while also identifying limitations such as inefficient memory usage, limited energy scalability, and poor resource distribution in current parallel implementations.
Desenvolvimento de estratégias para melhorar a disponibilidade de fósforo em solos através da fermentação em estado sólido
(Universidade Federal de São Carlos, 2025-05-27) Rodrigues, Natalia Alvarez; Farinas, Cristiane Sanchez; https://lattes.cnpq.br/9933650905615452; https://orcid.org/0000-0002-9985-190X; https://lattes.cnpq.br/8928436632437953; https://orcid.org/0000-0003-0073-6520
The growing concern over the environmental impacts of intensive agriculture has intensified the search for sustainable alternatives, such as bioinoculants and biofertilizers. Among these strategies, the use of phosphate-solubilizing microorganisms (PSMs) is particularly promising, as they can reduce dependence on conventional phosphate fertilizers, whose production is associated with significant environmental damage. Solid-state fermentation (SSF) has emerged as a favorable cultivation method in this context, enabling the valorization of agro-industrial residues as fermentation substrates, thereby supporting circular economy principles. Given this scenario, this thesis aimed to investigate biotechnological strategies for producing phosphate biofertilizers via the cultivation of PSMs through SSF. Initially, the study focused on improving the solubilization process of phosphate rocks (PRs) through SSF by optimizing oxalic acid production by the fungus Aspergillus niger. Using sequential experimental designs, several variables were assessed, including substrate composition, sucrose supplementation, and methanol addition. A substrate mixture of sugarcane bagasse and soybean bran (1:1 w w-1) was identified as the most effective for stimulating oxalic acid synthesis. Methanol addition proved to be a key factor in this process, increasing acid excretion threefold. Under optimized conditions - 7% methanol and 5 g of sucrose per kg of dry substrate (d.s.) -, substantial solubilization of Bayóvar, Itafós, and Registro PRs was achieved. Furthermore, the SSF process facilitated the release of organic P from the substrate itself, due to the production of enzymes such as phosphatases and cellulases. For Bayóvar PR, a maximum soluble P release of 12.1 g kg-1 d.s. was observed, corresponding to a solubilization efficiency of 63.8%. Based on these promising results, the process was evaluated in bench scale using a multilayer packed-bed bioreactor (PBB). Although the PBB system showed adequate operational behavior, methanol volatilization likely limited the solubilization efficiency to 24.6%. On the other hand, in situ drying of the fermented solids within the PBB successfully preserved both microbial viability and acid phosphatase activity over a 34-day storage period. Furthermore, greenhouse experiments revealed that substituting 50% of chemical fertilizer with the biofertilizers developed on a lab-scale did not compromise plant performance. Additionally, a different approach using the fungus Trichoderma harzianum was also explored, with a focus on optimize sporulation and enhancing the production of metabolites related to increased P acquisition by plants, such as indole derivatives and flavonoids. Cultivation was performed using beer draff and wheat straw as substrates. After optimization of aeration, proportion of substrates and inoculum size in 0.5 L PBBs, high values were achieved: 1.08 × 10¹⁰ spores g⁻¹ dry matter (DM), 511.3 µg g⁻¹ DM of indole derivatives, and 2.2 mg g⁻¹ DM of total flavonoids. At bench scale (22 L PBB), the system still supported good sporulation (1 × 10⁹ spores g⁻¹ DM) and indole derivative production (688 µg g⁻¹ DM). However, overheating of up to 16.5°C above the optimal temperature (25°C) resulted in significant axial and radial thermal gradients, which notably impaired the production of acid phosphatase and flavonoids. Overall, this work provides significant contributions to the development of phosphate biofertilizers through SSF, identifying both promising strategies and key challenges for future advancement.
Controle de Amaranthus spp. utilizando o potencial alelopático de Brassicas
(Universidade Federal de São Carlos, 2025-05-27) Barbosa, Murilo Rafael; Monquero, Patricia Andrea; https://lattes.cnpq.br/2766526793830455; https://lattes.cnpq.br/3752261793713523
The Amaranthus genus has presented biotypes with resistance to different herbicides, making its management increasingly challenging. Alternatively, species of the Brassica genus stand out for their allelopathic potential, due to the release of chemical substances known as allelochemicals, capable of inhibiting the growth of organic plants. The present study aimed to evaluate different concentrations of dry extracts of the aerial part of canola (Brassica napus), mustard (Brassica juncea) and forage radish (Raphanus sativus) in the suppression of purple pigweed (Amaranthus hybridus), creeping pigweed (Amaranthus deflexus) and common pigweed (Amaranthus viridis) and to identify the classes of phytochemical constituents with potential allelopathic activity presented in the aqueous extract of Brassicas. The experimental design was completely randomized, in a 5x3 factorial arrangement, with five concentrations (100%, 50%, 25% and 12% and 0% as control) of dry extracts of the aerial part of Brassica species in the suppression of Amaranthus species, in four replicates. In the germination bioassay, Amaranthus species were sown in petri dishes soaked with 2 mL of each concentration and kept in BOD at 25°C and a 12-hour photoperiod, evaluating the germination percentage (%G) and the germination speed index (IVG). In the initial development bioassay, 5 ml of each extract was used on pre-germinated seeds in a container containing vermiculite, subjected to evaluation regarding hypocotyl and root length, phytotoxicity and fresh mass. A phytochemical test was performed based on qualitative reactions (color change, precipitate formation and physicochemical properties) in 2 ml samples of the crude extract of each Brassica for reducing sugars, alkaloids, anthraquinones, coumarins, steroids, flavonoids, phenols, glycosides, saponins, tannins and terpenes. An inhibitory effect on germination was observed in all concentrations of the extracts used, with greater inhibition at 50% and 100%. However, when the 12% concentration was used, there was a stimulation of the development of the weed species. The species A. deflexus was the most sensitive to the extracts, presenting the highest rate of germination inhibition. As the concentrations of the extracts increased, the IVG of the weed species was negatively affected, with a 100% reduction in the seeds exposed to the highest concentration (100%). There were no statistical differences in relation to the length of the hypocotyl, however, there was a reduction in the development of the root system of the seedlings, leading to poor development of the aerial part. The extracts induced phytotoxicity in the seedlings as the concentrations increased, culminating in necrosis, making it impossible to analyze the fresh mass. The phytochemical analysis of the extracts identified the presence of seven classes of chemical compounds: coumarin, steroid, flavonoid, phenol, glycoside, tannin and terpene. These results suggest that the different extracts used exert an allelopathic function on the germination and development of the weed species.
Propostas de ensino por investigação sobre quantidade de movimento e corrente elétrica para alunos com TDAH
(Universidade Federal de São Carlos, 2025-05-27) Oliveira, Gabriel Rinhel de; Veraszto, Estéfano Vizconde; Colato, Alexandre; https://lattes.cnpq.br/5460973924624757; https://orcid.org/0000-0003-0076-007X
In this work the aim is to discuss Attention Deficit Hyperactivity Disorder (ADHD), the teaching of physics and the impact that limited knowledge on the part of teachers can have on the education of students. As well as an introduction to ADHD, the main characteristics of the condition and the impact it can have on students’ development and learning were presented. Strategies developed by various authors as alternatives to traditional teaching were also presented in order to ensure a better education for students. Based on some of the proposals presented, namely Inquiry Teaching, two lesson plans were developed for secondary school students. The aim is to give students an active role in order to encourage the development of their reasoning and critical thinking skills.
A ontologia indireta de Merleau-Ponty e o vínculo entre arte, ciência e filosofia: Entre van Gogh, Einstein e Heisenberg: a imaginação enquanto capacidade cognitiva e expressiva do real
(Universidade Federal de São Carlos, 2025-05-27) Tonon, Hugo; Moutinho, Luiz Damon Santos; https://lattes.cnpq.br/9475267722538751; https://lattes.cnpq.br/2459404101194228
This thesis investigates the complementarity between art, science, and philosophy, based on Merleau-Ponty's indirect ontology and the analysis of scientific concepts and practices. Starting from van Gogh's work and Kolmogorov's idea of turbulence, we argue that imaginative cognition is a means of expressing and perceiving the world's meaning. Analyzing Merleau-Ponty's great rationalism, which integrates different forms of knowledge, and the practices of scientists like Heisenberg and Einstein, who used imagination to revolutionize physics, we conclude that expressive complementarity enriches our understanding of reality, uniting art, science, and philosophy.