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    Efeito do camu-camu (Myrciaria dubia), da creatina e do exercício resistido no desempenho físico, variáveis metabólicas e saúde intestinal de ratos wistar
    (Universidade Federal de Viçosa, 2026-07-03) Abrantes, Lívia Carvalho Sette; Della Lucia, Ceres Mattos; http://lattes.cnpq.br/3001836124836023
    A prática regular de exercício resistido (ER) promove aumento da força e da massa muscular, mas também pode elevar a produção de espécies reativas de oxigênio, modulando o balanço redox e as adaptações metabólicas ao treinamento. Nesse contexto, alimentos ricos em compostos bioativos, como o camu-camu (Myrciaria dubia), e suplementos ergogênicos, como a creatina, podem atuar de forma complementar sobre o desempenho físico, o metabolismo muscular e a saúde intestinal. Assim, esta tese teve como objetivo avaliar o efeito do camu-camu (Myrciaria dubia), da creatina e do exercício resistido sobre o desempenho físico, variáveis metabólicas e a saúde intestinal de ratos Wistar. Inicialmente, foi realizada uma revisão sistemática sobre os efeitos de berries brasileiras na saúde intestinal. No estudo experimental, foram utilizados 64 ratos Wistar machos adultos, distribuídos em oito grupos experimentais, de acordo com a dieta recebida e a realização ou não de treinamento resistido: AIN-93M, camu-camu (200mg/kg), creatina (300 mg/kg peso na primeira semana e 50 mg/kg nas outras sete) e camu- camu associado à creatina, nos grupos treinados e não treinados. O treinamento foi realizado em escada vertical durante oito semanas, sendo a carga máxima carregada avaliada a cada duas semanas. Ao final do experimento, foram coletadas amostras de sangue, fezes, cólon e músculos esqueléticos para análises bioquímicas, histológicas, do balanço oxidativo, da atividade de ATPase, do glicogênio muscular, da composição mineral, de parâmetros fecais, do pH cecal e dos ácidos graxos de cadeia curta. Os dados foram analisados utilizando os softwares GraphPad Prism 10.4.1 e SPSS 23, adotando-se nível de significância de 5%. A revisão sistemática mostrou que berries brasileiras apresentam potencial para modular a microbiota intestinal, favorecer a produção de ácidos graxos de cadeia curta, melhorar marcadores relacionados à integridade da barreira intestinal e reduzir processos inflamatórios e oxidativos. No estudo experimental, a associação entre camu-camu e creatina, especialmente quando combinada ao exercício resistido, promoveu respostas musculares favoráveis, incluindo modulação do balanço oxidativo, aumento da atividade de enzimas antioxidantes, maior atividade de ATPase, maior armazenamento de glicogênio muscular, alterações na composição mineral e melhora progressiva do desempenho físico. No cólon, as intervenções promoveram adaptações funcionais e morfométricas, sem evidências de comprometimento da homeostase intestinal. A associação entre camu-camu e creatina modulou a atividade de enzimas antioxidantes, enquanto o exercício resistido favoreceu a atividade total de ATPase e aumentou a concentração de ácidos graxos de cadeia curta, principalmente butirato. Também foram observadas alterações específicas na composição mineral e em parâmetros histomorfométricos do cólon. Em conjunto, os resultados demonstram que o camu-camu, a creatina e o exercício resistido promovem respostas complementares e dependentes do tecido avaliado, com repercussões sobre o desempenho físico, o metabolismo energético, o balanço redox e a saúde intestinal de ratos Wistar. Palavras-chave: atividade física; força; nutrição; suplementação; berries brasileiras; exercício físico.
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    From agreements to markets: trade integration and agricultural export dynamics in Latin America
    (Universidade Federal de Viçosa, 2026-07-02) Silva, Raphael Gomes da; Silva, Fernanda Aparecida; http://lattes.cnpq.br/5572343001011680
    This thesis examines trade agreements as a policy tool in Latin America and addresses two complementary questions about their effectiveness. Since the 1990s, regional trade agreements have proliferated dramatically as countries turned away from stalled multilateral negotiations, and these agreements have evolved substantially in scope, moving beyond tariff reductions to incorporate provisions on investment, services, environmental standards, labor regulations, and other areas that can influence trade, directly or indirectly. As these agreements have become widely used and vary substantially in scale, scope, and coverage, important questions arise about whether their content matters for their success and whether the heterogeneity across agreements translates into different impacts on trade. This dissertation addresses these questions through two complementary papers focused on Latin America. The first paper asks whether agreement design matters, specifically whether the depth and modernization of negotiated provisions shape their impact on trade. We develop the Depth Index of Trade Agreements (DITA), a new multidimensional measure of agreement depth, constructed via factor analysis with endogenous provision weights, applied to 681 agreements from 1970 to 2019. Our results show that the Pacific Alliance and Central America lag one decade behind North American standards, while South America and the Caribbean lag by two to three decades. Our gravity model estimates confirm that agreement design matters for trade creation: deeper agreements generate substantially larger trade effects, with high-depth agreements producing trade increases of up to 82.6\% in the long run within the Americas, compared to insignificant effects for low-depth agreements. The second paper examines whether regionalism worked in South America, assessing the success of Mercosur and its first wave of agreements with Chile (1996), Bolivia (1997), Peru (2005), and Colombia and Ecuador (2005) in promoting agricultural trade and export diversification in South America. We employ a structural gravity model that incorporates the actual liberalization schedules for each agreement and decomposes trade growth into its intensive and extensive margincomponents, allowing us to identify not only whether these agreements generated trade but also when and through which margin. Mercosur itself produced strong and persistent trade effects across all phases of liberalization, while the associated agreements show more limited and phase-dependent results: Colombia and Ecuador generated positive agricultural trade effects concentrated in specific liberalization stages, whereas Chile, Bolivia, and Peru show little evidence of trade creation. Export diversification occurred across all agreements, with the share of previously undertraded products rising substantially, though trade growth came primarily through the intensive margin, with the only clear exception being Mercosur–Bolivia. Together, the two papers suggest that trade agreements are a more conditional policy tool than often assumed. Their effectiveness depends on both the depth of their commitments and the structural conditions of the partner economies. For Latin America, where heterogeneity in trade policy approaches is substantial, these findings underscore the need to reassess how agreements are designed and what they are expected to achieve. Keywords: trade agreements; international trade. gravity model; Mercosur; agricultural trade;
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    Modelagem computacional de sítios de ligação em proteínas: da comparação estrutural ao aprendizado em grafos
    (Universidade Federal de Viçosa, 2026-03-09) Paiva, Vinícius de Almeida; Silveira, Sabrina de Azevedo; http://lattes.cnpq.br/2889736880174687
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    Effects of plot size on the estimation of genetic parameters in sugarcane families
    (Crop Breeding and Applied Biotechnology, 2006) Leite, Mauro Sérgio de Oliveira; Peternelli, Luiz Alexandre; Barbosa, Márcio Henrique Pereira
    An optimization of the use of resources in sugarcane breeding programs that would not interfere with the genetic evaluations is desirable and of great importance. The costs could be reduced and the chances of success would be higher through the possibility of investing rationally in a larger number of available genetic resources. Our study evaluated the smallest number of rows per plots of sugarcane families for yield traits; the variations in the parameter estimates for different plot sizes were discussed; and the ideal plot size was estimated by the maximum curvature method. Plot reduction leads to gradual CV increases and interferes with the ratio CVg/CVe, which in some cases dropped to values below one unit, indicating experimental inaccuracy. Heritability estimates decrease with plot size. The maximum curvature method showed that 2-row plots are enough to evaluate all characteristics.
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    Genetic diversity among Capsicum accessions using RAPD markers
    (Crop Breeding and Applied Biotechnology, 2006) Costa, Fabiane Rabelo da; Pereira, Telma Nair Santana; Vitória, Angela Pierre; Campos, Karina Pereira de; Rodrigues, Rosana; Silva, Derly Henriques da; Pereira, Messias Gonzaga
    Genus Capsicum has 27 species, being five domesticated and 22 semi-domesticated and wild ones. For an enhanced use of the germplasm in breeding programs it is necessary to know the accessions in the collections, to identify them and evaluate the genetic diversity. Objectives of this research were to quantify the genetic diversity among 70 Capsicum accessions, confirm their identification and verified possible duplicated accessions, using RAPD markers. Results showed that there is genetic diversity within and among species and were in agreement with botanical and morpho-agronomic classifications. The identification of 53 accessions was confirmed (16 C. annuum, 7 C. frutescens, 14 C. baccatum and 16 C. chinense) and among botanically non-identified accessions results suggested that six belong to C. baccatum and five to C. chinense. The most distinct accession was UENF 1620, probably a wild species that is not represented in the collection yet.