7 research outputs found

    Selectivity of Herbicide 2,4-D, Isolated and In Association, In Pre-Emergency in Culture of Açaí

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    With the growth of acai planted areas, further studies on herbicides are needed in this palm tree of great potential. Thus, the present work aimed to evaluate the selectivity of the 2,4-D herbicide applied in pre-emergence, isolated, and in association, with acai seedlings. The experimental design was randomized blocks with 4 replications. Increasing doses of 2,4-D isolated (502.5, 1,005 and 2,010 g e a ha) and associated with picloram (960 g e. a ha), triclopyr (960 g e. a ha) were applied as treatments. and glyphosate (1,110 g e. a ha), one more control without application. At 3,7,14,21,28 and 35 DAA, the percentage of phytointoxication, height (cm), and the number of leaves of the acai seedlings were determined. At the end of the evaluations (35 DAA), the 2,4-D isolated applications obtained the best results, with low phytointoxication visual percentage, higher plants, and a larger number of leaves, showing selective culture. However, the association of the 2,4-D herbicides with picloram, in all doses used, had negative effects on the evaluated parameters, evidencing the non-selectivity of the acai berry crop

    Impact of rearing systems in the Eastern Amazon on cholesterol, β-carotene and vitamin E homologues in steer

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    IntroductionThe quality of meat, with a focus on compounds important for human health, is directly related to the rearing systems in which the animals are produced. The search for a balanced diet, with an emphasis on low cholesterol and adequate levels of vitamins, aligns with society’s emphasis on healthy eating, directly correlated with the importance of the offer made by producers for the cattle’s diet.Objective and methodologyThe objective was to verify the impact of different rearing systems, in the Eastern Amazon, during the rainy season, on the concentrations of vitamins (A, E) and cholesterol in the muscle (Longissimus lumborum) of crossbred Nelore cattle, castrated, aged between 24 and 36 months, and weighing between 410 and 628 kg. Twelve animals, from each of the three pasture rearing systems: native pasture in flooded areas of Monte Alegre; native pasture in a flooded area of Santa Cruz do Arari; and pasture cultivated on dry land in São Miguel do Guamá, all located in Pará, Brazil—were sampled in commercial slaughterhouses.ResultsA notable influence was observed in the concentrations of β-carotene (p < 0.01), α-Tocopherol (p = 0.02), β-Tocopherol (p < 0.01) and the combined sum of β-Tocotrienol and γ-Tocopherol (p < 0.01), as well as δ-Tocopherol (p < 0.01) when contrasting extensive with intensive systems (confinement). However, there was a difference in the content of vitamins and cholesterol between the isolated extensive systems, or between the four rearing systems (p > 0.05). Extensive systems, mainly in Monte Alegre, demonstrated greater amounts of α-Tocopherol and δ-Tocopherol.ConclusionOn the other hand, the intensive system exhibited higher levels of other investigated compounds, clarifying the nutritional variations generated by different livestock rearing practices in the region. Therefore, the results obtained are innovative in the Eastern Amazon, Brazil, in addition to inspiring the development of new research to meet other demands in this field, and achieve additional results, such as determining which meat, coming from cattle in production systems in the country, presents the better compositional quality of vitamins and lipids

    Características morfogênicas, estruturais, acúmulo de forragem e composição química de capim-massai, submetido à adubação nitrogenada

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    The objective of this study was to evaluate the morphogenic, structural, biomass accumulation and chemical composition of plants of Massai grass submitted to six nitrogen doses (0, 100, 200, 300, 400 and 600 kg of N / ha / year) in a completely randomized design, with six replications in plots of 12 m². Urea was used as the Nitrogen source, whose doses were divided in six applications during the rainy season, according to the treatments. Forage harvesting was done at a residue height of 15 cm, when the canopy intercepted 95% of the incident light at an average of five internal points on the plot with the Accupar model LP-80® canopy analyzer. Data were submitted to variance analysis and regression, the significance level was 0.05 of the linear and quadratic coefficient and the coefficient of determination. There was (p0,05) para os teores de fibra insolúvel em detergente neutro, ácido e hemicelulose, componentes esses que limitam a digestão. A adubação nitrogenada favorece a morfogênese, produção de forragem e as características qualitativas de capim-Massai

    Structure and productivity of tanzania grass subjected to different defoliation frequencies

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    The objective of the present study was to evaluate the effect of different frequencies of defoliation at fixed periods on the structural and productive characteristics of Tanzania grass (Panicum maximum) under Am climate conditions in 2014. The experimental design was in complete randomized blocks with six treatments corresponding to six frequencies of defoliation (14, 21, 28, 35, 42, and 49 days) and five repetitions. The data was submitted to regression analysis. The light interception (LI) increased (P <0.05) in an asymptotic way with increasing rest periods. The maximum light interception was 98% and occurred at 42 days of regrowth. The leaf area index (LAI) and the dry matter accumulation increased (P <0.05) linearly varying from 3.6 to 7.1 and from 880.3 to 4051.7 kg.ha-1 of forage dry matter in the frequencies 14-49 days, respectively. The height ranged 44-119 cm at frequencies 14-49 days, respectively. The frequency of defoliation at 95% LI is related to the rest period of 29 days, where the Tanzania grass canopy presented around 63 cm height, critical LAI of 5.1, and forage dry matter accumulation of 2,160 kg ha-1.Objetivou-se com este trabalho avaliar o efeito de diferentes frequências de desfolhação em períodos fixos sob as características estruturais e produtivas do dossel de capim-Tanzânia (Panicum maximum Jacq) em condições climáticas Am no ano de 2014. O delineamento experimental foi em blocos casualizados com seis tratamentos correspondentes a seis frequências de desfolhação (14; 21; 28; 35; 42 e 49 dias) e cinco repetições e os dados foram submetidos a análise de regressão. A interceptação luminosa (IL) aumentou (P<0,05) de maneira assintótica com o aumento dos períodos de descanso, no qual a máxima interceptação de luz foi de 98% e ocorreu aos 42 dias de rebrotação. O índice de área foliar (IAF) e o acúmulo de matéria seca, aumentaram (P<0,05) linearmente variando de 3,6 a 7,1 e de 880,3 a 4051,7 kg.ha-1 de matéria seca de forragem, nas frequências de 14 a 49 dias, respectivamente. A altura variou de 44 a 119 cm nas frequências de 14 a 49 dias, respectivamente. A frequência de desfolhação que representa uma IL de 95% está relacionada ao período de descanso de 29 dias, em que o dossel de capim-Tanzânia apresentou altura em torno de 63 cm, IAF crítico de 5,1 e acúmulo de matéria seca de forragem de 2.160 kg.ha-1

    Da ética ambiental à bioética ambiental: antecedentes, trajetórias e perspectivas

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    Health-status outcomes with invasive or conservative care in coronary disease

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    BACKGROUND In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline

    Initial invasive or conservative strategy for stable coronary disease

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    BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used
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