171 research outputs found

    Flutuação populacional de artrópodes no milho em áreas de transição para produção orgânica.

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    Com o objetivo de construir um modelo de desenvolvimento agrícola sustentável em um assentamento no Estado de Goiás, procurou-se viabilizar o processo de transição de um sistema convencional de produção de grãos para um sistema sustentável, que recupere o solo, preserve os recursos naturais e o capital social. Neste trabalho, estudou-se o efeito de diferentes coberturas vegetais (adubos verdes) semeadas no mês de abril sobre a população de artropódes da parte aérea do milho semeado nas águas (outubro-novembro)

    The link between Terra Preta de Índio and the use of charcoal to improve soil quality.

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    Amazonian Dark Earth ? Terra Preta de Índio. Characterization The Amazonian Dark Earth (ADE) or Terra Preta de Índio shows normally a plaggic, terric or hortic horizons. These horizons are identified by the dark matrix colors of the top layers, and presence of ceramics and charcoal pieces. The more widely accepted theory about the origin of these epipedons is that they were improved by Amerindian populations in Pre Colombian Indian settlements. The tophorizons on ADE sites show some differences on soil chemical, physical and hydraulic properties compared to the adjacent soils in the region. The tophorizon shows typically high amounts of P, calcium (Ca), magnesium (Mg) relative to the surrounding soils. The high amounts of soil organic matter (SOM) and black carbon strongly influence the color, the structure and the hydraulic properties. The texture is lighter and the workability of the ADE is easier, and the drainage is, habitually, very good. Because of their easy workability and longer lasting in relation to surrounding soils, the local population intensively uses those sites. ADE sites seem to be a very resilient soil type to keep their good soil physical qualities as when submitted to an intensive soil management. In this paper we discuss some investigations concerning a better characterization and expansion of the knowledge of ADE sites. Moreover the approach to reproduce those soils using as key component charcoal residues are also reviewed and discussed. Terra Preta reproduction Many experiment, monitoring and modeling of the dynamic of the water, nutrients and soil organic matter in soil with addition of charcoal are on ongoing research in Manaus. The first experiment at field conditions, investigating the effect of a combination of mineral fertilizers and charcoal as a mean of reducing nutrient leaching tested anual crops in a randomized complete block design with 15 treatments with five replication including organic amendment combinations with and without fertilization (compost, chicken manure, litter and charcoal). Plots fertilized with NPK and lime + charcoal application showed better plant growth as plots fertilized alone. Our first experiment with Banana showed some better mineral nutrition for N in the plants growing on plots were charcoal were applied

    Strong magneto-elastic coupling and polar properties in orthorhombic Eu1-xYxMnO3 manganite

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    This work reports an experimental investigation of the magneto-elastic coupling and polarization character of magnetic phases of the orthorhombic Eu1-xYxMnO3 system at low temperatures. The temperature dependence of the polarization reversal curves clearly reveals the existence of a reentrant improper ferroelectric phase for x = 0.2 and 0.3. Although a ferroelectric phase is also stable for x = 0.4, we have no experimental evidence that it vanishing at finite temperatures. From these results and those obtained from other experimental techniques, the corresponding (x,T) phase diagram was traced, yet yielding significant differences with regard to previous reports. An expressive magneto-elastic coupling is revealed by changes observed in both Mn-O bond lengths and Mn-O1-Mn bond angle at the magnetic phase transitions, obtained by temperature dependence of synchrotron x-ray diffraction experiments. Furthermore, signatures of the lattice deformations across the magnetic phase transitions were evidenced by anomalies in the temperature dependence of the lattice mode involving rotations of the MnO6 octahedra. These anomalies confirm the important role of the spin-phonon coupling in these materials.Comment: 12 Figures, 2 Table

    Obese rats are more vulnerable to inflammation, genotoxicity and oxidative stress induced by coal dust inhalation than non-obese rats

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    Obesity is an important nutritional disorder worldwide. Its association with environmental pollution may trigger an increase in oxidative stress and inflammatory parameters. Coal is a resource used throughout the world as an important fuel source for generating electricity. The ashes released by the coal combustion cause serious problems for human health due to their high toxicity and their capacity to bioaccumulate. The aim of this work was to investigate the effects of coal dust inhalation in the organs of obese and non-obese Wistar rats. Pro-inflammatory cytokines, oxidative stress, oxidative damage, histological analysis, comet assay, and micronuclei were investigated. Both obesity and coal dust inhalation increased the pro-inflammatory cytokines IL-1β and TNF-α and decreased HSP70 levels in serum, however, in obese animals that inhaled coal dust these changes were more pronounced. Liver histological analysis showed severe microvesicular steatosis in obese animals that inhaled coal dust. Lung histologic investigation showed abnormalities in lung structure of animals exposed to coal dust and showed severe lung distensibility in obese animals exposed to coal dust

    Host life-history traits predict haemosporidian parasite prevalence in tanagers (Aves: Thraupidae)

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    Vector-borne parasites are important ecological drivers influencing life-history evolution in birds by increasing host mortality or susceptibility to new diseases. Therefore, understanding why vulnerability to infection varies within a host clade is a crucial task for conservation biology and for understanding macroecological life-history patterns. Here, we studied the relationship of avian life-history traits and climate on the prevalence of Plasmodium and Parahaemoproteus parasites. We sampled 3569 individual birds belonging to 53 species of the family Thraupidae. Individuals were captured from 2007 to 2018 at 92 locations. We created 2 phylogenetic generalized least-squares models with Plasmodium and Parahaemoproteus prevalence as our response variables, and with the following predictor variables: climate PC1, climate PC2, body size, mixed-species flock participation, incubation period, migration, nest height, foraging height, forest cover, and diet. We found that Parahaemoproteus and Plasmodium prevalence was higher in species inhabiting open habitats. Tanager species with longer incubation periods had higher Parahaemoproteus prevalence as well, and we hypothesize that these longer incubation periods overlap with maximum vector abundances, resulting in a higher probability of infection among adult hosts during their incubation period and among chicks. Lastly, we found that Plasmodium prevalence was higher in species without migratory behaviour, with mixed-species flock participation, and with an omnivorous or animal-derived diet. We discuss the consequences of higher infection prevalence in relation to life-history traits in tanagers.Fil: Aguiar de Souza Penha, Victor. Universidade Federal do Paraná; BrasilFil: Maia Chaves Bicalho Domingos, Fabricius. Universidade Federal do Paraná; BrasilFil: Fecchio, Alan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Bell, Jeffrey A.. University of South Dakota; Estados UnidosFil: Weckstein, Jason D.. No especifíca;Fil: Ricklefs, Robert E.. University of Missouri; Estados UnidosFil: Martins Braga, Erika. Universidade Federal de Minas Gerais; BrasilFil: de Abreu Moreira, Patrícia. Universidade Federal de Ouro Preto; BrasilFil: Soares, Leticia. University of Western Australia; AustraliaFil: Latta, Steven. No especifíca;Fil: Tolesano Pascoli, Graziela. Universidade do Brasília; BrasilFil: Alquezar, Renata Duarte. Universidade do Brasília; BrasilFil: Del Claro, Kleber. Universidade Federal de Uberlandia; BrasilFil: Tonelli Manica, Lilian. Universidade Federal do Paraná; Brasi

    Monitoring Adherence to Asthma Inhalers Using the InspirerMundi App: Analysis of Real-World, Medium-Term Feasibility Studies

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    Background: Poor medication adherence is a major challenge in asthma and objective assessment of inhaler adherence is needed. InspirerMundi app aims to monitor inhaler adherence while turning it into a positive experience through gamification and social support. Objective: We assessed the medium-term feasibility of the InspirerMundi app to monitor inhaler adherence in real-world patients with persistent asthma (treated with daily inhaled medication). In addition, we attempted to identify the characteristics of the patients related to higher app use. Methods: Two real-world multicenter observational studies, with one initial face-to-face visit and a 4-month telephone interview, were conducted in 29 secondary care centers from Portugal. During an initial face-to-face visit, patients were invited to use the app daily to register their asthma medication intakes. A scheduled intake was considered taken when patients took a photo of the medication (inhaler, blister, or others) using the image-based medication detection tool. Medication adherence was calculated as the number of doses taken as a percentage of the number scheduled. Interacting with the app ≥30 days was used as the cut-off for higher app use. Results: A total of 114 patients {median 20 [percentile 25 to percentile 75 (P25-P75) 16-36] years, 62% adults} were invited, 107 (94%) installed the app and 83 (73%) completed the 4-month interview. Patients interacted with the app for a median of 18 [3-45] days, translated on a median use rate of 15 [3-38]%. Median inhaler adherence assessed through the app was 34 [4-73]% when considering all scheduled inhalations for the study period. Inhaler adherence assessed was not significantly correlated with self-reported estimates. Median adherence for oral and other medication was 41 [6-83]% and 43 [3-73]%, respectively. Patients with higher app use were slightly older (p = 0.012), more frequently taking medication for other health conditions (p = 0.040), and more frequently prescribed long-acting muscarinic antagonists (LAMA, p = 0.024). After 4 months, Control of Allergic Rhinitis and Asthma Test (CARAT) scores improved (p < 0.001), but no differences between patients interacting with the app for 30 days or less were seen. Conclusions: The InspirerMundi app was feasible to monitor inhaler adherence in patients with persistent asthma. The persistent use of this mHealth technology varies widely. A better understanding of characteristics related to higher app use is still needed before effectiveness studies are undertaken.info:eu-repo/semantics/publishedVersio

    Prevention of hypertension in patients with pre-hypertension: protocol for the PREVER-prevention trial

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    <p>Abstract</p> <p>Background</p> <p>Blood pressure (BP) within pre-hypertensive levels confers higher cardiovascular risk and is an intermediate stage for full hypertension, which develops in an annual rate of 7 out of 100 individuals with 40 to 50 years of age. Non-drug interventions to prevent hypertension have had low effectiveness. In individuals with previous cardiovascular disease or diabetes, the use of BP-lowering agents reduces the incidence of major cardiovascular events. In the absence of higher baseline risk, the use of BP agents reduces the incidence of hypertension. The PREVER-prevention trial aims to investigate the efficacy, safety and feasibility of a population-based intervention to prevent the incidence of hypertension and the development of target-organ damage.</p> <p>Methods</p> <p>This is a randomized, double-blind, placebo-controlled clinical trial, with participants aged 30 to 70 years, with pre-hypertension. The trial arms will be chlorthalidone 12.5 mg plus amiloride 2.5 mg or identical placebo. The primary outcomes will be the incidence of hypertension, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new sub-clinical atherosclerosis, and sudden death. The study will last 18 months. The sample size was calculated on the basis of an incidence of hypertension of 14% in the control group, a size effect of 40%, power of 85% and P alpha of 5%, resulting in 625 participants per group. The project was approved by the Ethics committee of each participating institution.</p> <p>Discussion</p> <p>The early use of blood pressure-lowering drugs, particularly diuretics, which act on the main mechanism of blood pressure rising with age, may prevent cardiovascular events and the incidence of hypertension in individuals with hypertension. If this intervention shows to be effective and safe in a population-based perspective, it could be the basis for an innovative public health program to prevent hypertension in Brazil.</p> <p>Trial Registration</p> <p>Clinical Trials <a href="http://www.clinicaltrials.gov/ct2/show/NCT00970931">NCT00970931</a>.</p
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