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Agricultura familiar no contexto da produção sustentável de café orgânico no Brasil e América Latina
(Universidade Federal de São Carlos, 2025-12-19) Araujo, Maria Isabel Rinaldo Pessôa de; Furnival, Ariadne Chloe Mary; https://lattes.cnpq.br/1291482506649810; https://orcid.org/0000-0002-2344-4400; https://lattes.cnpq.br/9243348503899322; https://orcid.org/0009-0001-7969-1734; Furnival, Ariadne Chloe Mary; Redin, Ezequiel; Costa, Luzia Sigoli Fernandes; https://lattes.cnpq.br/1291482506649810; https://lattes.cnpq.br/4594328596786231; https://lattes.cnpq.br/8110248272001369; https://orcid.org/0000-0002-2344-4400; https://orcid.org/0000-0002-3750-8225; https://orcid.org/0000-0001-8530-4000
This dissertation proposes an analysis of the concepts and practices related to family farming and sustainable organic coffee production in Brazil and Latin America. Coffee (Coffea sp.) is a perennial crop of great global importance, with Brazil being one of the world's leading producers and exporters. Historically, Brazilian coffee farming has adopted intensive agricultural practices, characterized by heavy use of chemical fertilizers, pesticides, and herbicides, which causes adverse environmental impacts, soil degradation, and risks to human health. In contrast, organic coffee farming is emerging as an alternative and sustainable agricultural system, based on the non-use of agrochemicals and rational soil management. Organic agriculture is defined by principles of health, ecology, justice, and care, promoting biodiversity, biological cycles, and soil biological activity. This model has gained global recognition, promising benefits for consumers, farmers, and the environment. The objective is to understand the different ways of defining and approaching family farming, taking into account its particularities and challenges, as well as to seek to understand the principles and practices of sustainable organic coffee production, highlighting its benefits for the environment, the economy, and society. We also sought to identify the main obstacles that family farmers face when trying to grow organic coffee in a sustainable manner. The methodological approach employed a systematic review of the literature, covering case studies and data from Brazil (São Paulo, Minas Gerais, Espírito Santo, Chapada Diamantina/Bahia) and Latin America (Mexico, Peru, Costa Rica, Colombia, and Bolivia), which generated a table with 11 studies focused on three themes: family farming, sustainable organic coffee production, and the challenges faced by family farmers in growing organic coffee. Although productivity in organic agriculture tends to be lower (20% to 25%) compared to conventional agriculture, certified Brazilian family farmers had 10% higher income and 30% higher profits, as well as greater market integration. However, the transition involves significant costs and a three-year transition period without a premium price. Diversification of income sources and support from cooperatives and producer organizations are crucial, as they facilitate technical assistance, financing, and marketing, providing a strategy for economic and social survival for family farmers. Organic certification is essential for access to differentiated markets, but marketing, especially for export, faces challenges such as bureaucracy, costs, and price fluctuations, which do not always result in the premium price expected by farmers. Social organization is a pillar for agroecological transition and improved living conditions. The analysis demonstrates the complexity of the transition to organic and sustainable coffee farming, highlighting the need for integrated approaches. Science and technology provide knowledge and socio-technical innovations, while society supports organizations, finances farmers, and ensures access to fair markets to guarantee sustainability and improved livelihoods for family farmers in Brazil and Latin America. Although organic agriculture offers undeniable environmental and social benefits, significant challenges remain that require continued support and effective public policies to fully realize its potential.
Função polinomial de primeiro grau: uma abordagem através de resolução de problemas
(Universidade Federal de São Carlos, 2025-12-19) Silva, Silas Pereira da; Pires, Rogério Fernando; https://lattes.cnpq.br/2795801064535157; https://lattes.cnpq.br/3687511709869880; Lima Junior, Haroldo Aleixo de ; Oliveira, Paulo César; https://lattes.cnpq.br/8361643043765037; https://lattes.cnpq.br/7516513469811353
This study aimed to investigate the implications of Problem Solving, articulated with the Theory of Registers of Semiotic Representation (TRSR), for the learning of the concept of First-Degree Polynomial Function by 10th-grade students from a public high school in the countryside of São Paulo state, Brazil. The investigation was guided by the following research question: What are the implications of using Problem Solving, supported by the Theory of Registers of Semiotic Representation, for the learning of the concept of First-Degree Polynomial Function? The study followed the assumptions of a qualitative approach and was structured according to the four phases of Didactic Engineering: preliminary analysis, a priori analysis, experimentation, and a posteriori analysis. The didactic sequence was organized into six interdependent sessions, grounded in the ten steps of Problem Solving, and composed of problem situations designed to mobilize and coordinate different registers of representation, such as natural language, algebraic, tabular, and graphical registers. This organization fostered the development of cognitive activities of formation, treatment, and conversion, enabling the analysis of transitions between registers and of phenomena of congruence and non-congruence. Sixteen students participated in the study, and the written productions generated throughout the didactic sequence constituted the corpus of analysis. The results indicated that, initially, students mobilized the registers of representation in a fragmented way; however, over the course of the didactic sequence, they showed progress in the coordination between different representations. Data analysis showed that the articulation between Problem Solving and the Theory of Registers of Semiotic Representation constitutes a consistent theoretical-methodological framework for understanding the processes of construction of mathematical knowledge. It is concluded that this articulation fostered the understanding of the First-Degree Polynomial Function as a model of variation and as an instrument for analyzing contextualized situations, promoting the development of more elaborated forms of mathematical thinking.
Coprodução de biodiesel e triacetina por interesterificação enzimática de óleo de babaçu com acetato de etila
(Universidade Federal de São Carlos, 2025-12-19) Nascimento, Camila Santos do; Tardioli, Paulo Waldir; https://lattes.cnpq.br/0808991927126468; https://lattes.cnpq.br/7046463044644622; Guimarães, José Renato; Esteves, Thais Suzane Milessi; https://lattes.cnpq.br/4550733668734212; https://lattes.cnpq.br/7000002745065879
The growing global demand for energy and the environmental impacts associated with the intensive use of fossil fuels have driven the search for more sustainable routes for biofuel production. In this context, biodiesel stands out as a renewable alternative, particularly in Brazil, where its blending with fossil diesel is mandatory and currently corresponds to 15% (v/v). The conventional production route, based on chemical transesterification, generates large amounts of low-value glycerol and requires additional purification steps. As an alternative, this study investigated the co-production of biodiesel and triacetin through the enzymatic interesterification of babassu oil with ethyl acetate, a more sustainable reagent and compatible with en-zymatic catalysis. The process was carried out using the commercial lipase Eversa® Transform 2.0, previously immobilized on a hydrophobic Purolite® C18 support to enhance biocatalyst stability and enable reuse. Initially, babassu oil was character-ized in terms of its physicochemical properties and fatty acid composition. Subse-quently, a Central Composite Rotational Design was applied to evaluate the effects of temperature and the oil-to-ethyl acetate molar ratio on the yield of fatty acid ethyl esters (FAEEs). The optimal conditions were validated in a mechanically stirred re-actor with conventional heating, and the effects of enzyme loading and ethyl acetate addition mode were investigated. Under the optimized conditions: 15% enzyme load-ing (w/w relative to the oil), gradual addition of ethyl acetate, a temperature of 38 °C, and 72 h of reaction, the system with conventional heating achieved yields of 53.83% FAEEs and 2.10% triacetin. The application of microwave-assisted heating enabled comparable yields in a significantly shorter reaction time, reaching 57.58% FAEEs and 3.53% triacetin in only 6 h. These results demonstrate the potential of the enzymatic interesterification of babassu oil with ethyl acetate as a more sustain-able alternative route for biodiesel production, combined with the generation of tri-acetin as a higher value-added coproduct, and highlight the advantages of micro-wave heating for process intensification.
Aspectos morfológicos e clínicos do manguito rotador em indivíduos com ombro congelado - Avaliação e tratamento
(Universidade Federal de São Carlos, 2025-12-19) Policastro, Pablo Oscar; Camargo, Paula Rezende; https://lattes.cnpq.br/7602596349127054; https://orcid.org/0000-0002-8961-4353; https://lattes.cnpq.br/4462600785871860; https://orcid.org/0000-0003-0434-2844; Struyf, Filip; Luque Suarez, Alejandro; Vaz, Marco Aurélio; Serrão, Fábio Viadanna; https://lattes.cnpq.br/2093718148536940; https://lattes.cnpq.br/8137335642635433; https://orcid.org/0000-0002-9128-9684; https://orcid.org/0000-0001-8803-3007; https://orcid.org/0000-0001-6741-3502; https://orcid.org/0000-0003-3655-9933
Frozen shoulder (FS) significantly impacts daily life, leading to pain, disability, anxiety, and sleep disturbances. Diagnosis and treatment focus in FS is mainly delivered to the joint capsule; however, little information is available about the contribution of the rotator cuff in this clinical condition. This thesis integrates a cross-sectional study, a randomized clinical trial and a qualitative study. Study 1: Objective: To assess the pennation angle (PA) and Muscle Thickness (MT) of the supraspinatus, infraspinatus, and teres minor muscles in individuals with FS and compare with healthy controls and to compare the PA and MT of these rotator cuff muscles in individuals with FS under muscle contraction and resting conditions. Methods: a cross-sectional study was conducted. Results: 92 participants were divided into a control group and a FS group. There were no differences in the PA and MT in any of the muscles at rest and under contraction when comparing individuals with FS and healthy controls. All muscles showed increased PA and MT under contraction when compared to rest in individuals with FS. Conclusion: PA and MT of the supraspinatus, infraspinatus, and teres minor muscles did not differ between individuals with FS and healthy controls. PA and MT were higher during contraction than at rest. Study 2: Objective: To compare the effects of adding eccentric exercises to a standardized programme that includes manual therapy, stretching, education, and exercise on shoulder function pain intensity, range of motion, quality of life, fear-avoidance beliefs, pain catastrophizing, satisfaction with the treatment, PA, and MT of the supraspinatus, infraspinatus, and teres minor muscles in individuals with primary FS. Methods: This is a two-arm parallel, single-blinded superiority-controlled clinical trial where 40 individuals were randomized. Results and Conclusion: There was no significant interaction in the shoulder function, pain intensity, range of motion, quality of life, fear-avoidance beliefs, pain catastrophizing, satisfaction with the treatment, PA, and MT of the supraspinatus, infraspinatus, and teres minor muscles. Significant time effects (p < 0.001) were observed across most outcomes. The addition of eccentric exercises was not superior to a standardized programme comprising manual therapy, stretching, education, and exercise in individuals with primary FS. Study 3: Objective: To explore the experiences, beliefs, and perceptions of individuals with primary FS after a physical therapy program. Methods: A qualitative study using thematic analysis was conducted in individuals with primary FS after a physical therapy program. Results and Conclusion: Ten participants were included. Three main themes were generated: (1) “My life before starting the treatment”, (2) “Experiencing the treatment”, and (3) “How I am after the treatment”. This study provided information about the experiences, beliefs, and perceptions of individuals with primary FS after a physical therapy program. Overall, participants focused on the FS condition and its consequences, as well as on treatments received and their clinical impact. These findings may help improve the management of FS, guide therapists in their clinical practice, and enhance patient-therapist interactions.
Integração de Bacillus subtilis e cobre no manejo do cancro cítrico
(Universidade Federal de São Carlos, 2025-12-19) Ramos, Luiz Otávio; Goés, Antonio; https://lattes.cnpq.br/0786750280869349; Jesus Junior, Waldir Cintra de; https://lattes.cnpq.br/2614953467362376; https://lattes.cnpq.br/0524609281948756; Moraes, Simone; Agápto, João; https://lattes.cnpq.br/5042766148748174; https://lattes.cnpq.br/5699962523528931
Brazilian citrus production, which leads the global orange market, is currently threatened by the accelerated spread of citrus canker, now present in 32.71% of orchard blocks and affecting more than 53 million trees. Control of the disease relies exclusively on copper-based compounds, resulting in excessive dependence and frequent applications that increase the risks of phytotoxicity, environmental contamination, and reduced sustainability of commercial orchards. This scenario exposes an urgent scientific gap: identifying alternative strategies capable of maintaining effective disease control while reducing the intensive use of copper, such as biological products formulated with Bacillus subtilis. This quantitative study evaluated the effectiveness of chemical management (copper), biological management (Bacillus subtilis), and integrated management (copper alternated with Bacillus subtilis) in three commercial sweet orange cultivars (Hamlin, Pera, and Valencia) over three consecutive seasons, conducted in commercial orchards located in the municipalities of Itatinga and Avaré, São Paulo, Brazil. The experiment followed a randomized block design with four treatments and one replication per treatment, assessing 30 plants per block. Disease severity was evaluated monthly using the diagrammatic scale proposed by Belasque Júnior et al. (2005), and epidemic progress was quantified using the Area Under the Disease Severity Progress Curve (AUDSPC). Productivity was determined by harvesting each evaluated plant, and all data were analyzed in RStudio using ANOVA and Tukey’s test at a 5% significance level. Results showed that copper was the most effective treatment, with severity ranging from 0 to 5% and AUDSPC values below 550 across all seasons and cultivars. Integrated management achieved control equivalent to biweekly copper applications while reducing the number of copper sprays by half, demonstrating promising potential to decrease dependency on this input. In contrast, Bacillus subtilis alone showed low efficacy, not differing from the untreated control in most evaluations. The cultivars displayed different susceptibility levels, with Hamlin being the most affected and Valencia the most tolerant. Rainfall had a strong influence on disease development, intensifying severity and reducing productivity in wetter years. In conclusion, copper remains the most effective strategy for controlling citrus canker; however, integrated management represents a viable alternative for reducing copper use, particularly in regions with high inoculum pressure. Bacillus subtilis alone showed limited performance, reinforcing the need for advances in sustainable alternatives to the current exclusively copper-based control approach.
Modificação de fibras de bagaço de cevada e uso em compósitos biodegradáveis de amido de milho produzidos por tape casting
(Universidade Federal de São Carlos, 2025-12-19) Castanho, Maria Natalia; Paiva, Jane Maria Faulstich de; https://lattes.cnpq.br/7926832511513537; https://lattes.cnpq.br/2807864150195202; Frollini, Elisabete; Nunes, Andréa Oliveira; Maia, Amanda Alves Domingos; Silva, Maria Lúcia Pereira Antunes; https://lattes.cnpq.br/2615524841845182; https://lattes.cnpq.br/7620659413250570; https://lattes.cnpq.br/7830680455593771; https://lattes.cnpq.br/9040916399114048
The use of starch to obtain biodegradable films of thermoplastic starch (TPS) presents several advantages, such as being derived from a natural, renewable, abundant, and low-cost source. However, starch films generally exhibit low tensile mechanical properties and high hydrophilicity. In this context, the study used brewer’s spent grain (BSG), considered a byproduct of the brewing industry, as reinforcement in corn starch–based composites. For this purpose, TPS composites plasticized with glycerol were developed using Farmal CS3650 corn starch, with an approximate composition of 28% amylose and 72% amylopectin. To produce the films, 10 wt% starch and 5 wt% glycerol were used, with the addition of 1 wt% barley bagasse fibers (unmodified, modified by alkaline treatment in sodium hydroxide (NaOH) solution, or carbonized at 200, 300, 400, and 500 °C). The films were produced using a microwave oven to heat the mixture, with pauses for manual stirring, and molded by tape casting, a technique that allows better thickness uniformity of the films compared to conventional casting. Tensile mechanical tests were performed, as well as Scanning Electron Microscopy (SEM) on fractured samples, Dynamic Mechanical Analysis (DMA), Thermogravimetric Analysis (TG/DTG), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), contact angle measurements, and soil biodegradation and phytotoxicity tests for possible agricultural application of the produced material. Improvements in tensile strength were observed for composites containing fibers carbonized at 400 °C (2.10 ± 0.09 MPa) and fibers modified by alkaline treatment (2.27 ± 0.16 MPa), representing increases of up to 51% compared to the TPS film without fiber incorporation (1.40 ± 0.11 MPa). Thermal analyses did not reveal significant differences in the thermal stability of the composites due to the low fiber content. The addition of modified fibers promoted a reduction in hydrophilicity and water absorption of the films. The incorporation of unmodified or alkali-treated fibers accelerated the biodegradation of the composites, whereas carbonized fibers maintained biodegradability similar to that of TPS. The produced films showed no phytotoxicity. Alkaline treatment and fiber carbonization proved to be promising strategies for obtaining composites with improved properties and sustainability. The developed composites show potential for applications in short-life biodegradable packaging and agricultural films, such as mulching and wraps for seeds and seedlings. Mechanical improvements and reduced hydrophilicity enhance the functional viability of materials developed. The use of agro-industrial waste (byproducts) and low-cost processes reinforces the sustainable character and application potential in environmentally responsible disposable products.
Impulsionamento de uma biblioteca virtual por meio de um plano de marketing: estudo de caso na UFMT
(Universidade Federal de São Carlos, 2025-12-19) Moreno, Olgarita Helena da Silva; Martins, Manoel Fernando; http://lattes.cnpq.br/3921504261628850; https://orcid.org/0000-0003-2787-5977; http://lattes.cnpq.br/3736874780732500; https://orcid.org/0009-0004-0292-6525; Oliveira, Heloá Cristina Camargo de; Rodrigues Netto, Miguel; http://lattes.cnpq.br/1449712413161729; http://lattes.cnpq.br/5892152879005889; https://orcid.org/0000-0003-2466-6678; https://orcid.org/0000-0002-6990-4572
The advancement of telecommunications and information technology has profoundly transformed human relations, impacting work, learning processes, and access to knowledge. In this context, libraries play a strategic role in information dissemination and are challenged to adapt to the dynamics of the digital era. The emergence of virtual libraries and digital books represents a significant innovation, expanding access to documentary records and strengthening remote support for teaching, research, and extension activities in higher education institutions. Despite these potentialities, reports from companies contracted by the Federal University of Mato Grosso (UFMT) indicate a low level of use of virtual platforms compared to the number of available licenses. In contrast, the empirical data of this research, obtained through questionnaires applied to 124 undergraduate students and 55 faculty members (totaling 179 respondents), reveal that most participants are aware of and report using virtual libraries, although in an irregular and uneven manner across courses and campuses. This mismatch indicates that the issue lies not only in lack of awareness but, above all, in the absence of effective institutional strategies for mediation, dissemination, and integration of these resources into academic practices. Based on this diagnosis, the research—characterized as a case study—resulted in the development of a marketing plan aimed at boosting the use of UFMT’s virtual libraries, constituting a technological product of the Professional Master’s Degree in Production Engineering. Among the main results, the study highlights the identification of barriers related to institutional communication, user training, and faculty engagement, as well as the proposal of targeted strategic actions, such as segmented campaigns, continuous training initiatives, integration of platforms into course syllabi, and strengthening of informational mediation. It is concluded that strengthening virtual libraries depends on coordinated action among institutional management, technical staff, and faculty, in order to transform the available informational potential into effective, continuous, and qualified use. By identifying gaps and proposing concrete interventions, this study contributes not only to expanding access to and use of virtual libraries at UFMT but also provides replicable insights for other higher education institutions facing similar challenges in the context of digital culture.