108 resultados para Philadelphia


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High soil acidity influences the availability of mineral nutrients and increases that of toxic aluminium (Al), which has a jeopardizing effect on plant growth. The objective of this research was to evaluate the effects of soil liming on the development of guava (Psidium guajava L.) plants, on soil chemical characteristics, and on fruit yield. The experiment was carried out at the Bebedouro Citrus Experimental Station, state of São Paulo, Brazil, in a Typic Hapludox soil, from August 1999 to March 2003. The treatments consisted of limestone dose: D0 = zero; D1 = half dose; D2 = total dose; D3 = 1.5 times the dose, and D4 = 2 times the dose to raise the V value to 70%. The doses corresponded to zero, 1.85, 3.71, 5.56, and 7.41tha(-1) applied to the upper soil layer (0-30cm deep) before planting. The results showed that liming caused an improvement in the evaluated soil chemical characteristics up to a depth of 60cm in soil samples both in the line and between lines. The highest fruit yields were obtained when the base saturation reached a value of 55% in the line and 62% between the lines. Foliar levels of calcium (Ca) and magnesium (Mg) were 8.8 and 2.5gkg-1, respectively. The highest limestone dose maintained the soil base saturation (at the layer of 0-20cm) in the line close to 55% during at least 40 months after the incorporation of limestone.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Citrus cultures have a fundamental importance to the Brazilian economy; certain aspects such as plant nutrition, yield, and fruit quality are vital for the citrus industry sustainability. The present study evaluated the nutritional status of manganese in adult Pear orange trees using different lime rates topically applied to the soil. The direct evaluation of lime rates effects on leaf manganese (Mn) levels revealed a decrease of the nutrient correlated to its increased, as well as passage of time between application and measurement. Foliar sampling 30 months after surface lime application evidenced a high correlation of foliar manganese levels with soil base saturation of 10-20 cm. Leaf manganese levels which showed a great probability of high productivity were between 33 and 70 mg kg-1.

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The objective was to study the effects of phosphorous (P) fertilization on nutritional and developmental aspects of growing mango plants. The mango plants were evaluated by soil chemical analyses, leaf chemical analyses, biological examination of plant growth, and the starting point of fruit production. Having this in view, an experiment was set up on 2 January 2003, at Flora, a farm in Uberlandia, state of Minas Gerais, Brazil. The soil was a clayish Oxisol. The doses at planting were: D0 = zero, D1 = 40, D2 = 100, D3 = 200, and D4 = 300 g of P2O5 plant-1. These doses at the beginning of the second year were multiplied by 1.5 and at the beginning of the third year by 2.0 and applied to the plants. The fertilizer used in this experiment was triple superphosphate (44% of P2O5.). During August of 2004, 2005, and 2006, soil samples were taken at a depth of 20 cm in between the plant rows. Leaf samples were taken during August of 2004 and 2005 to determine macro- and micronutrient contents in the leaves. Plant stem diameter was measured during January of 2004 and 2005. Plant height and crown radius were measured during January of 2005 and fruit production in 2005 and 2006. Fertilizer applications increased the level of P in the soil but significantly influenced plant performance only after the second year. The effects of phosphorus on mango plants take place slowly leading to increments in plant stem diameter only at the third year. Fruit set was not influenced by phosphorous fertilization.

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Potassium (K) leaching is affected by soil texture and available K, among other factors. In this experiment, effects of soil texture and K availability on K distribution were studied in the presence of roots, with no excess water. Soils from two 6-year field experiments on a sandy clay loam and a clay soil fertilized yearly with 0, 60, 120, and 180 kg ha-1 of K2O were accommodated in pots that received 90 kg ha-1 of K2O. Soybean was grown up to its full bloom (R2). Under field conditions, K leaching below the arable layer increased with K rates, but the effect was less noticeable in the clay soil. Potassium leaching in a sandy clay loam soil was related to soil K contents from prior fertilizations. With no excess water, in the presence of soybean roots, K distribution in the profile was significant in the lighter textured soil but was not apparent on the heavier textured soil.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Cation mobility in acidic soils with low organic-matter contents depends not only on sorption intensity but also on the solubility of the species present in soil solution. In general, the following leaching gradient is observed: potassium (K+) magnesium (Mg2+) calcium (Ca2+) aluminum (Al3+). To minimize nutrient losses and ameliorate the subsoil, soil solution must be changed, favoring higher mobility of M2+ (metal ions) forms. This would be theoretically possible if plant residues were kept on the soil surface. An experiment was conducted in pots containing a Distroferric Red Latosol, with soil solution extractors installed at two depths. Pearl millet, black oat, and oilseed radish residues were laid on the soil surface, and nitrogen (as ammonium nitrate) was applied at rates ranging from 0 to 150mgkg-1. Corn was grown for 52 days. Except for K+ and ammonium (NH4 +), nitrogen rates and plant residues had little effect upon the concentrations and forms of the elements in the soil solution. Presence of cover crop residues on soil surface decreased the effect of nitrogen fertilizer on Ca leaching. More than 90% of the Ca2+, Mg2+, and K+ were found as free ions. The Al3+ was almost totally complexed as Al(OH3)0. Nitrogen application increased the concentrations of almost all the ions in soil solution, including Al3+, although there was no modification in the leaching gradient.

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The literature widely recognizes that shift workers have more health complaints than the general population. The objective of this study was to describe the prevalence of sleep complaints and verify the polysomnographic (PSG) variables of shift workers in two Brazilian nuclear power plants. We carried out a subjective evaluation with a sleep questionnaire. Based on these results, the interviewees that reported sleep-related complaints were referred for polysomnographic evaluation. of the 327 volunteers initially evaluated by the sleep questionnaire, 113 (35%) reported sleep complaints; they were significantly older, had higher body mass index (BMI), and worked more years on shifts than those without sleep complaints. of these 113, 90 met criteria for various sleep disorders: 30 (9%) showed obstructive sleep apnea (OSA), 18 (5.5%) showed limb movement, and 42 (13%) evidenced both sleep problems and had a significantly higher proportion of sleep stage 1 and arousals compared with the 23 shift workers that had no indices of sleep problems. The present study found that 90 (27.5%) of the evaluated participants met the PSG criteria of some type of clinical sleep disorder. This high proportion should be investigated for associations with other aspects of work, such as working hours, working schedule, years performing shift work, and access to health services. Due to the strong association between sleep disorders and the incidence of fatigue and sleepiness, the evaluation of the sleep patterns and complaints of shift workers is essential and should be considered to be one of the basic strategies of industry to prevent accidents.

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A general view of the electroanalytical applications of metal-salen complexes is discussed in this review. The family of Schiff bases derived from ethylenediamine and ortho-phenolic aldehydes (N,N'-ethylenebis(salicylideneiminato) - salen) and their complexes of various transition metals, such as Al, Ce, Co, Cu, Cr, Fe, Ga, Hg, Mn, Mo, Ni, and V have been used in many fields of chemical research for a wide range of applications such as catalysts for the oxygenation of organic molecules, epoxidation of alkenes, oxidation of hydrocarbons and many other catalyzed reactions; as electrocatalyst for novel sensors development; and mimicking the catalytic functions of enzymes. A brief history of the synthesis and reactivity of metal-salen complexes will be presented. The potentialities and possibilities of metal-Salen complexes modified electrodes in the development of electrochemical sensors as well as other types of sensors, their construction and methods of fabrication, and the potential application of these modified electrodes will be illustrated and discussed.

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Objective: HIV infection is exacerbated through additional pro-atherogenic mechanisms related to the processes of immune activation, inflammation, coagulation, and the modification of lipoproteins (e.g., particles of high density lipoprotein), contributing to increased cardiovascular risk. The aim of this study was to analyze the serum concentrations of myeloperoxidase (MPO) and other laboratory parameters in HIV-infected patients treated or not with antiretroviral drugs compared to non-infected individuals.Materials/Methods: The study included 154 volunteers: 47 non-infected individuals (control group - CON), 27 infected and untreated individuals (NTARv group) and 80 treated individuals (TARV group). We analyzed the counts of CD4+ lymphocytes and the viral load of the infected patients, along with the blood count, fasting glucose, total serum cholesterol (CHOL), HDL cholesterol, LDL cholesterol, triglycerides, MPO and high-sensitivity C-reactive protein (CRP) of all study participants.Results: There were significant increases in glucose, CHOL, LDL cholesterol, and triglycerides in the TARV group and significant reductions in the levels of HDL cholesterol for the TARV and NTARV groups. Significantly elevated levels of Hs-CRP were observed only in the TARV group, while levels of MPO were significantly higher in the TARV and NTARV groups compared to the control group. A correlation of MPO with Hs-CRP (r = 0.21, p = 0.032) was observed for HIV-infected patients, but MPO did not correlate significantly with the other analyzed parameters.Conclusions: The investigation of early biomarkers for cardiovascular risk evaluation, such as MPO, contributes to the clinical monitoring of HIV-infected individuals. The serum levels of MPO correlated with Hs-CRP and were high in HIV-infected individuals, indicating a possible predictor of cardiovascular events in these patients. (c) 2012 Elsevier B.V. All rights reserved.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Bucioli, SA, de Abreu, LC, Valenti, VE, and Vannucchi, H. Carnitine supplementation effects on nonenzymatic antioxidants in young rats submitted to exhaustive exercise stress. J Strength Cond Res 26(6): 1695-1700, 2012-Previous studies have demonstrated that exercise stress increases oxidative stress in rats. However, antioxidant supplement therapy effects on reactive oxygen substances are conflicting. We evaluated the effects of carnitine on renal nonenzymatic antioxidants in young rats submitted to exhaustive exercise stress. Wistar rats were divided into 3 groups: (a) control group (not submitted to exercise stress), (b) exercise stress group, and (c) exercise stress and carnitine group. The rats from group 3 were treated with gavage administration of 1 ml of carnitine (5 mg.kg(-1)) for 7 consecutive days. The animals from groups 2 and 3 were submitted to a bout of swimming exhaustive exercise stress. Kidney samples were analyzed for reactive substances to thiobarbituric acid by malondialdehyde (MDA), reduced glutathione (GSH), and vitamin-E levels. Carnitine treatment attenuated MDA increase caused by exercise stress (1:0.16 +/- 0.02 vs. 2:0.34 +/- 0.07 vs. 3:0.1 +/- 0.01 mmmol per milligram of protein; p < 0.0001). It also increased the renal levels of GSH (1:23 +/- 4 vs. 2:23 +/- 2 vs. 3:58 +/- 9 mu mol per gram of protein; p, 0.0001); however, it did not change renal vitamin E (1:24 +/- 5 vs. 2:27 +/- 1 vs. 3:28 +/- 5 mu M per gram of tissue; p < 0.001). In conclusion, carnitine improved oxidative stress and partially improved the nonenzymatic antioxidant activity in young rats submitted to exhaustive exercise stress.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)