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Ingestão de microplásticos por diferentes guildas tróficas em um reservatório tropical
(Universidade Federal de Lavras, 2026-02-13) Rabelo, Luana Carolina da Silva; Bueno, Alessandra Angélica de Pádua; Vieira, Larissa Fonseca Andrade; Herrera, Daphine Ramiro; Salvador, Gilberto Nepomuceno; Pompeu, Paulo dos Santos
Microplastic pollution has emerged as a significant threat to continental aquatic ecosystems, particularly in tropical reservoirs, where substantial knowledge gaps remain. This study assessed microplastic ingestion by fish belonging to different trophic guilds in the Furnas Hydroelectric Reservoir, Minas Gerais, Brazil, investigating patterns of abundance, composition, and associated ecological drivers. A total of 180 individuals representing nine species distributed among piscivorous, invertivorous, omnivorous, detritivorous, and herbivorous guilds were analyzed. Stomach contents were subjected to chemical digestion using hydrogen peroxide, followed by filtration and stereomicroscopic analysis, with particles classified according to type and color. A representative subsample was analyzed using Raman spectroscopy for polymer identification. The results revealed significant differences in microplastic ingestion among trophic guilds, with higher abundances observed in invertivorous species, highlighting the influence of feeding behavior and habitat use on contaminant exposure. Fragments and fibers were the predominant particle categories, mainly black and transparent, suggesting multiple contamination sources and high bioavailability. Raman spectroscopy confirmed the predominance of polyethylene terephthalate, followed by polystyrene and polypropylene, as well as the presence of associated pigments. These findings reinforce the role of tropical reservoirs as important microplastic retention zones and emphasize the relevance of trophic guilds as predictors of susceptibility to ingestion, contributing to the understanding of ecological mechanisms underlying microplastic contamination and supporting the development of monitoring and mitigation strategies in freshwater ecosystems. Keywords: Plastic debris; Raman spectroscopy; Polyethylene terephthalate; Environmental contamination.
Sono, estresse e uso de mídias digitais em universitários brasileiros: perfis comportamentais e impactos na saúde mental e atividade física
(Universidade Federal de Lavras, 2026-02-24) Ferreira, Darlene Isabel; Andrade, Eric Francelino; Rogatto, Priscila Carneiro Valim; Bertolini, Natalia Oliveira
Sleep quality has been widely associated with physical and mental well-being, especially in academic contexts characterized by high levels of stress and constant exposure to digital technologies. This project brings together two independent yet complementary studies that investigate different dimensions of sleep health in university students. This population often experiences irregular sleep patterns, elevated stress, and excessive use of digital media, negatively impacting mental health and promoting sedentary behavior. The first study (n = 757) assessed daytime napping (sociodemographic data), perceived stress (PSS-14), sleep quality (PSQI), and daytime sleepiness (ESS) among university students through an online questionnaire (snowball sampling). Women (68% of the sample) showed a higher frequency of napping (93.5% vs. 86.8%; p = 0.007), greater use of naps for stress relief (60%; p = 0.002), and higher PSS-14 and ESS scores. K-means cluster analysis identified three profiles: “Sleep disturbances” (high latency/stress), “Short naps” (better sleep), and “More naps” (younger/sleepier). The second study (n = 2,205) examined sociodemographic data, short-video dependence (DEVIC), mental health (GHQ-12), sleep (PSQI), and physical activity (IPAQ-SF). Women (61%) exhibited higher DEVIC dependence (mood modification/control), greater anxiety/depression symptoms, and poorer sleep quality, with an average social media use of 180 minutes per day. K-means cluster analysis revealed three profiles: “Higher physical activity” (good sleep/high Metabolic Equivalents of Task), “Higher video addiction” (younger/poorer sleep/sedentary), and “Women with higher education” (poor sleep). Both studies converge in identifying women and young individuals as vulnerable groups, with napping behavior and short-video consumption organizing into adaptive versus risk profiles, highlighting the need for institutional interventions focused on sleep hygiene and the conscious use of digital media. Keywords: Sleep quality; Digital media consumption; Stress; Physical activity
Análise epidemiológica da saúde mental de professores universitários no cenário após pandemia de coronavírus em uma cidade do interior de minas gerais – Brasil
(Universidade Federal de Lavras, 2025-03-28) Sant´Ana, Márcia Carvalho; Graciano, Miriam Monteiro de Castro; Ferreira, Ricardo Barcelos; Moura, Rodrigo Ferreira de; Mati, Vitor Luís Tenório
The COVID-19 pandemic brought about several changes in educational institutions worldwide. Many questions arose from these changes, one of which is whether they could affect professors' mental health. This study aims to determine the prevalence of common, non-psychotic mental disorders in higher education professors from public and private institutions, in different programs after the start of the COVID-19 pandemic in a municipality of the Minas Gerais countryside in Brazil. This is a cross-sectional study, with data collected through self-administered forms and questionnaires, sent by email and social media to the departments through the institutions affiliated with the study. Variables, such as changes in methodology for distance learning, age, gender, years of professional experience, study program, and a self-administered questionnaire for screening common non-psychotic mental disorders (SRQ-20), were analyzed. The study showed that, of the 129 participants, 49.6% are women, 68% are married, and 52% also teach graduate programs; 69% are dedicated exclusively to teaching; 14% reported dissatisfaction with the teaching profession and 61% with remuneration; 92% used remote teaching during the pandemic; and 19% underwent psychiatric treatment before the pandemic and 19% were undergoing treatment at the time the survey was conducted. It was also observed that 100% reported having been vaccinated against COVID-19 and 26% feared returning to on-site classes. Regarding mental health assessment, 37 professors (28.6%) presented a score higher than 7 points on the SRQ-20. The highest scores consisted of positive correlation analyses for dissatisfaction with the profession, remuneration, and past and current treatment for psychiatric disorders. Based on the data collected, a high percentage of professors with probable mental illness after the COVID-19 pandemic was detected. There are few studies on this subject within this group of professionals. Therefore, it is essential to study the process of work-related mental illness to develop intervention strategies that reduce mental disorders by promoting actions on risk and protective factors, improving the quality of life of professors. Keywords: COVID-19; mental health; university professors.
Physicochemical characterization, quantification phenolic compounds, and instrumental sensorial analysis using bionic sensors of cachaça aged in barrels of wood species
(Universidade Federal de Lavras, 2026-01-26) Fernandes, Antonia Isadora; Cardoso, Maria das Graças; Santiago, Wilder Douglas; Teixeira, Maria Luisa; Bonesio, Mariana de Rezende; Ratkovich, Nicolas Rios
Cachaça is a fermented-distilled beverage obtained from the must of raw sugarcane, with an alcohol content between 38 and 48% v/v at 20°C. Throughout its production stages, congeners are formed, which are responsible for its peculiar and distinctive organoleptic characteristics. The storage/aging process of the Beverage, the only non-mandatory stage in the production chain, ensures greater sensory complexity and added value, thanks to molecules extracted from the barrel surface that react with molecules formed during the other stages of the production chain. Although the aging process normally occurs in barrels made of American or European oak, new native Brazilian plant species and exotic species stand out for this purpose. The use of these species help to reduce the cost of importing and maintaining oak barrels and to guarantee greater diversity of products to be marketed. Among these species are amburana, balsam, jequitibá, freijó, and eucalyptus. The physicochemical composition, and quantification of phenolic and volatile compounds present in samples of cachaça aged in fourteen native and exotic plant species were analyzed, as well as the instrumental analysis of sensory characteristics using electronic tongue and nose tests. The analysis of physicochemical parameters was performed according to Normative Instruction No. 24 of November 8, 2005, from the Ministry of Agriculture and Livestock (MAPA). The analyses of phenolic compounds were performed by high-performance liquid chromatography. The instrumental analyses of aromas and flavors were performed according to established methods for electronic tongue and nose tests. As a result, the parameters of all the samples were lower than the maximum limits proposed by current legislation. Liquid chromatography analyses quantified thirteen phenolic compounds, with concentrations ranging from not detected to 75.2 mg L⁻¹. Bionic sensors distinguished 134 distinct aromas, which were classified into categories and subcategories. Perceptions of flavors related to umami, acidity, and aftertastes superior to those of the reference sample (non-aged sample) were identified. Perceptions related to bitterness and astringency were lower than those of the reference. This study highlights the viability of using native Brazilian and exotic woods for aging cachaça to ensure the production of new aged products in accordance with legislation and with high complexity and sensory harmony. The application of bionic sensors in the analysis of aged cachaça has also shown promise for evaluating the sensory characteristics of the final product, as well as throughout the production chain by identifying atypical and/or undesirable characteristics and allowing, when necessary, the rapid implementation of corrective actions to ensure a high-quality product, in addition to assisting the consumer at the time of purchase by enabling the choice of a product that better suits their personal interests. Keywords: Aging. Native woods. Bionic sensors. Volatile compounds. Phenolic compounds.
Relação entre trabalho infantil e resultados escolares: análise dos microdados do ensino fundamental em Minas Gerais no período de 2009 a 2019
(Universidade Federal de Lavras, 2025-12-04) Domingues, Betania da Silva Cunha; Garcias, Marcos de Oliveira; Cabral, Eloisa Helena de Souza; Kawamura, Henrique Coelho
Child labor remains a reality in Brazil, hindering the complete development of the learning process for thousands of children and adolescents and acting as a factor in the intergenerational transmission of poverty. The general objective of this research was to analyze how child labor affected the school performance of students in municipalities of Minas Gerais between 2009 and 2019. To this end, a quantitative research methodology with an exploratory and descriptive approach was used to demonstrate student performance on the tests of the Basic Education Assessment System (Saeb) from 2009 to 2019, employing a multiple linear regression model. In addition, a temporal overview of the different types of children and adolescent labor between 2009 and 2019 was developed to verify the incidence of these types, measuring their growth and reduction over the period, as well as their impact on the learning process. The research revealed that the double burden of work, both domestic and external work, negatively and more markedly affects 5th-grade elementary school students. Keywords: Child Labor, Human Capital, School Performance, SAEB (Basic Education Evaluation System).