Alternativas à agricultura de corte e queima em processos de transição agroecológica: um desafio para a agricultura amazónica

A paisagem agrícola amazônica abriga uma diversidade de situações onde, com frequência, ocorre a prática do corte-e-queima para preparo de área para plantio. A constatação dos impactos adversos dessa prática evidencia a necessidade de promover a sua substituição via sistemas alternativos que viabilizem a produção agrícola, reduzindo ou evitando o uso do fogo. Embora muitas alternativas disponíveis tenham características de passos de processos de transição agroecológica e a ampliação da sua adoção possa ser beneficiada pela implantação de estratégias de transição social agroecológica, este tipo de prática não vem sendo abordado em estudos sobre processos de transição agroecológica. Este artigo se propõe a analisar exemplos de práticas alternativas à derruba-e-queima na Amazônia brasileira, à luz de processos de transição agroecológica e social agroecológica, como subsídio ao avanço no seu desenvolvimento e adoção, e à formulação e implantação de políticas públicas.The Amazonian agricultural landscape is home to a diversity of situations where often occurs the practice of slash-and-burn for land preparation for planting. The observation of the adverse impacts of this practice highlights the need to promote its replacement via alternative systems that enable agricultural production, reducing or avoiding the use of fire. Although many of the available alternatives have characteristics of ecological transition process steps and the expansion of its adoption can be benefited by the implementation of social-ecological transition strategies, this type of practice has not been addressed in studies on agroecological transition processes. This article sets out to analyse examples of alternatives to practices of slash-and-burn in the Brazilian Amazon, in the light of processes of agroeclogical and social-agroecological transitions, as subsidy to the advancement in their development and adoption and to the formulation and implementation of public policies.Eje A1 Sistemas de producción de base agroecológica (Trabajos científicos)Facultad de Ciencias Agrarias y Forestale

Alternativas à agricultura de corte e queima em processos de transição agroecológica: um desafio para a agricultura amazónica

A paisagem agrícola amazônica abriga uma diversidade de situações onde, com frequência, ocorre a prática do corte-e-queima para preparo de área para plantio. A constatação dos impactos adversos dessa prática evidencia a necessidade de promover a sua substituição via sistemas alternativos que viabilizem a produção agrícola, reduzindo ou evitando o uso do fogo. Embora muitas alternativas disponíveis tenham características de passos de processos de transição agroecológica e a ampliação da sua adoção possa ser beneficiada pela implantação de estratégias de transição social agroecológica, este tipo de prática não vem sendo abordado em estudos sobre processos de transição agroecológica. Este artigo se propõe a analisar exemplos de práticas alternativas à derruba-e-queima na Amazônia brasileira, à luz de processos de transição agroecológica e social agroecológica, como subsídio ao avanço no seu desenvolvimento e adoção, e à formulação e implantação de políticas públicas.The Amazonian agricultural landscape is home to a diversity of situations where often occurs the practice of slash-and-burn for land preparation for planting. The observation of the adverse impacts of this practice highlights the need to promote its replacement via alternative systems that enable agricultural production, reducing or avoiding the use of fire. Although many of the available alternatives have characteristics of ecological transition process steps and the expansion of its adoption can be benefited by the implementation of social-ecological transition strategies, this type of practice has not been addressed in studies on agroecological transition processes. This article sets out to analyse examples of alternatives to practices of slash-and-burn in the Brazilian Amazon, in the light of processes of agroeclogical and social-agroecological transitions, as subsidy to the advancement in their development and adoption and to the formulation and implementation of public policies.Eje A1 Sistemas de producción de base agroecológica (Trabajos científicos)Facultad de Ciencias Agrarias y Forestale

Oral delivery of fish oil in oil-in-water nanoemulsion : development, colloidal stability and modulatory effect on in vivo inflammatory induction in mice

To improve the oral absorption of fish oil and test its anti-inflammatory effect, a fish oil nanoemulsion was developed using cis-4,7,10,13,16,19-docosahexaenoic fatty acid as a biomarker for oral administration. The colloidal stability tests of the fish oil nanoemulsion showed an average size of 155.44 nm ± 6.46 (4 °C); 163.04 nm ± 9.97 (25 °C) and polydispersity index 0.22 ± 0.02 (4 °C), 0.21 ± 0.02 (25 °C), indicating systems with low polydispersity and stable droplets. The fish oil nanoemulsion did not alter the cell viability of the RAW 264.7 macrophages and, at a concentration of 0.024 mg/mL, was kinetically incorporated into the cells after 18 h of contact. The nanoemulsion was maintained in the gastrointestinal region for a significantly shorter period of time (p ≤ 0.05) compared to the intake of fish oil in free form. Inflammatory tests demonstrated that nanoemulsion and fish oil showed less (p ≤ 0.05) neutrophil infiltration after 24h of sepsis induction and there was a significant reduction (p ≤ 0.05) in the volume of paw edema in female adult Balb/c mice who received the nanoemulsion diet compared to the other experimental groups (control, formalin, fish oil and sunflower oil). These results indicate that the fish oil nanoemulsion was significantly effective in the dietary conditions tested here, presenting satisfactory responses in the modulation of inflammatory disorders, demonstrating interesting and beneficial nutraceutical effects

Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains

Ruiz JC, D'Afonseca V, Silva A, et al. Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains. PLoS ONE. 2011;6(4): e18551.Background: Corynebacterium pseudotuberculosis, a Gram-positive, facultative intracellular pathogen, is the etiologic agent of the disease known as caseous lymphadenitis (CL). CL mainly affects small ruminants, such as goats and sheep; it also causes infections in humans, though rarely. This species is distributed worldwide, but it has the most serious economic impact in Oceania, Africa and South America. Although C. pseudotuberculosis causes major health and productivity problems for livestock, little is known about the molecular basis of its pathogenicity. Methodology and Findings: We characterized two C. pseudotuberculosis genomes (Cp1002, isolated from goats; and CpC231, isolated from sheep). Analysis of the predicted genomes showed high similarity in genomic architecture, gene content and genetic order. When C. pseudotuberculosis was compared with other Corynebacterium species, it became evident that this pathogenic species has lost numerous genes, resulting in one of the smallest genomes in the genus. Other differences that could be part of the adaptation to pathogenicity include a lower GC content, of about 52%, and a reduced gene repertoire. The C. pseudotuberculosis genome also includes seven putative pathogenicity islands, which contain several classical virulence factors, including genes for fimbrial subunits, adhesion factors, iron uptake and secreted toxins. Additionally, all of the virulence factors in the islands have characteristics that indicate horizontal transfer. Conclusions: These particular genome characteristics of C. pseudotuberculosis, as well as its acquired virulence factors in pathogenicity islands, provide evidence of its lifestyle and of the pathogenicity pathways used by this pathogen in the infection process. All genomes cited in this study are available in the NCBI Genbank database (http://www.ncbi.nlm.nih.gov/genbank/) under accession numbers CP001809 and CP001829

A global experiment on motivating social distancing during the COVID-19 pandemic

Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges