781 resultados para application of pesticides


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Successive applications of pig slurry and pig deep litter may lead to an accumulation of copper (Cu) and zinc (Zn) fractions in the soil profile. The objective of this study was to evaluate the Cu and Zn forms and accumulation in a Sandy Typic Hapludalf soil after long-term application of pig slurry and deep litter. In March 2010, eight years after initiating an experiment in Braço do Norte, Santa Catarina (SC), Brazil, on a Sandy Typic Hapludalf soil, soil samples were collected from the 0-2.5, 2.5-5.0, 5-10 and 10-15 cm layers in treatments consisting of no manure application (control) and with applications of pig slurry and deep litter at two levels: the single and double rate of N requirement for maize and black oat succession. The soil was dried, ground in an agate mortar and analyzed for Cu and Zn contents by 0.01 mol L-1 EDTA and chemically fractionated to determine Cu and Zn. The applications of Pig deep litter and slurry at doses equivalent to 90 kg ha-1 N increased the contents of available Cu and Zn in the surface soil layer, if the double of this dose was applied in pig deep litter or double this dose in pig slurry, Cu and Zn migrated to a depth of 15 cm. Copper is accumulated mainly in the organic and residual fractions, and zinc preferentially in the fraction linked to clay minerals, especially in the surface soil layers.

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BACKGROUND AND OBJECTIVE: Theoretically myocardial angiogenesis of laser injury can be further enhanced by the addition of angiogenic growth factors. The influence of the way of administration of these factors on vascular growth around the channels is still unclear. MATERIALS AND METHODS: 18 pigs (mean weight 72 +/- 5.2 kg) were randomized to either triads of transmyocardial laser revascularization (TMLR) channels (group 1, n = 6) or isolated channels (group 2, n = 6), or a control group (n = 6). The animals had injections of bovine bone derived growth factor mixture either in the center of the triads in group 1 or within the channels themselves in group 2. Animals were sacrificed one month later for histological analysis. RESULTS: The vascular densities of myocardial areas within the triads of group 1 and around the channels in group 2 were significantly larger than in the control group: 15.2 +/- 3.7/mm2 and 14.2 +/- 3.5/mm2 respectively vs 5.3 +/- 1.6/mm2 (p < 0.001 for both differences). Differences of densities between group 1 and 2 were not statistically significant (p = 0.6). CONCLUSIONS: In this porcine model, the addition of a bovine bone derived growth factor mixture to TMLR significantly stimulates angiogenesis in the areas adjacent to the channels. The place of injection does not influence the angiogenesis intensity.

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One of the most important problems in optical pattern recognition by correlation is the appearance of sidelobes in the correlation plane, which causes false alarms. We present a method that eliminate sidelobes of up to a given height if certain conditions are satisfied. The method can be applied to any generalized synthetic discriminant function filter and is capable of rejecting lateral peaks that are even higher than the central correlation. Satisfactory results were obtained in both computer simulations and optical implementation.

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Selostus: Typen ja fosforin kulkeutuminen pinta- ja salaojavalunnassa lietelannalla ja NKP-lannoitteella lannoitetulta nurmelta

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A form of increasing the efficiency of N fertilizer is by coating urea with polymers to reduce ammonia volatilization. The aim of this study was to evaluate the effect of polymer-coated urea on the control of ammonia volatilization, yield and nutritional characteristics of maize. The experiment was carried out during one maize growing cycle in 2009/10 on a Geric Ferralsol, inUberlândia, MG, Brazil. Nitrogen fertilizers were applied as topdressing on the soil surface in the following urea treatments: polymer-coated urea at rates of 45, 67.5 and 90 kg ha-1 N and one control treatment (no N), in randomized blocks with four replications. Nitrogen application had a favorable effect on N concentrations in leaves and grains, Soil Plant Analysis Development (SPAD) chlorophyll meter readings and on grain yield, where as coated urea had no effect on the volatilization rates, SPAD readings and N leaf and grain concentration, nor on grain yield in comparison to conventional fertilization.

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It has been suggested that Ménière's disease is part of a polyganglionitis in which symptoms result from the reactivation of neurotropic virus within the internal auditory canal, and that intratympanic applications of an antiviral agent might be an efficient therapy. In 2002, we performed a pilot study ending with encouraging results. Control of vertigo was achieved in 80% of the 17 patients included. We present here a prospective, double-blind study, with a 2-year follow-up, in 29 patients referred by ENT practitioners for a surgical treatment after failure of a medical therapy. The participation in the study was offered to patients prior to surgery. A solution of ganciclovir 50 mg/ml or of NaCl 9% was delivered for 10 consecutive days via a microwick inserted into the tympanic membrane in the direction of the round window or through a ventilation tube. One patient was withdrawn from the study immediately after the end of the injections. He could not complete the follow-up period, because of persisting vertigo. As he had received the placebo, he was then treated with the solution of ganciclovir. Symptoms persisted and he underwent a vestibular neurectomy. Among the remaining 28 patients, surgery could be postponed in 22 (81%). Surgery remained necessary to control vertigo in 3 patients from the group that received the antiviral agent, and in 3 from the control group. Using an analogical scale, patients of both groups indicated a similar improvement of their health immediately after the intratympanic injections. The scores obtained with a 36-item short-form health survey quality of life questionnaire and the Dizziness Handicap Inventory were also similar for both groups. In conclusion, most patients were improved after the intratympanic injections, but there was no obvious difference between the treated and control groups. The benefit might be due to the middle ear ventilation or reflect an improvement in the patients' emotional state.

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Lime application recommendations for amendment of soil acidity in sugarcane were developed with a burnt cane harvesting system in mind. Sugarcane is now harvested in most areas without burning, and lime application for amendment of soil acidity in this system in which the sugarcane crop residue remains on the ground has been carried out without a scientific basis. The aim of this study was to evaluate the changes in soil acidity and stalk and sugar yield with different rates of surface application of calcium, magnesium silicate, and gypsum in ratoon cane. The experiment was performed after the 3rd harvest of the variety SP 81-3250 in a commercial green sugarcane plantation of the São Luiz Sugar Mill (47º 25' 33" W; 21º 59' 46" S), located in Pirassununga, São Paulo, in southeast Brazil. A factorial arrangement of four Ca-Mg silicate rates (0, 850, 1700, and 3400 kg ha-1) and two gypsum rates (0 and 1700 kg ha-1) was used in the experiment. After 12 months, the experiment was harvested and technological measurements of stalk and sugar yield were made. After harvest, soil samples were taken at the depths of 0.00-0.05, 0.05-0.10, 0.10-0.20, 0.20-0.40, and 0.40-0.60 m in all plots, and the following determinations were made: soil pH in CaCl2, organic matter, P, S, K, Ca, Mg, H+Al, Al, Si, and base saturation. The results show that the application of gypsum reduced the exchangeable Al3+ content and Al saturation below 0.05 m, and increased the Ca2+ concentration in the whole profile, the Mg2+ content below 0.10 m, K+ below 0.4 m, and base saturation below 0.20 m. This contributed to the effect of surface application of silicate on amendment of soil acidity reaching deeper layers. From the results of this study, it may be concluded that the silicate rate recommended may be too low, since the greater rates used in this experiment showed greater reduction in soil acidity, higher levels of nutrients at greater depths and an increase in stalk and sugar yield.

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The use of organic fertilizers and the inoculation of mycorrhizal fungi in the cultivation of oil crops is essential to reduce production costs and minimize negative impacts on natural resources. A field experiment was conducted in an Argissolo Amarelo (Ultisol) with the aim of evaluating the effects of fertilizer application and inoculation of arbuscular mycorrhizal fungi on the growth attributes of sunflower (Helianthus annuus L.) and on soil chemical properties. The experiment was conducted at the Federal University of Rio Grande do Norte, Brazil, using a randomized block design with three replicates in a 4 × 2 factorial arrangement consisting of four treatments in regard to application of organic fertilizer (liquid biofertilizer, cow urine, mineral fertilizer, and unfertilized control) and two treatments in regard to arbuscular mycorrhizal fungi (with and without mycorrhizal fungi). The results showed that the physiological attributes of relative growth rate and leaf weight ratio were positively influenced by fertilization, compared to the control treatment, likely brought about by the supply of nutrients from the fertilizers applied. The growth and productivity attributes were positively affected by mycorrhization.

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The design of appropriate multifractal analysis algorithms, able to correctly characterize the scaling properties of multifractal systems from experimental, discretized data, is a major challenge in the study of such scale invariant systems. In the recent years, a growing interest for the application of the microcanonical formalism has taken place, as it allows a precise localization of the fractal components as well as a statistical characterization of the system. In this paper, we deal with the specific problems arising when systems that are strictly monofractal are analyzed using some standard microcanonical multifractal methods. We discuss the adaptations of these methods needed to give an appropriate treatment of monofractal systems.

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BACKGROUND: Direct-infusion ESI-MS/MS is a powerful approach for the identification of substances in complex mixtures. The aim of this work was to investigate its applicability to the toxicological screening of blood samples. A simple protein precipitation was used, followed by a 15 min infusion of the extract in the mass spectrometer. RESULTS: The application of the procedure to commercial quality controls and authentic post-mortem blood samples demonstrated that the direct-infusion ESI-MS/MS approach enables the simultaneous identification of substances that require different chromatographic conditions. However, poor sensitivity was observed for benzodiazepine, amphetamines and opiate compounds. CONCLUSION: Considering the facile implementation and positive performance of direct-infusion ESI-MS/MS, this approach may to be a valuable complementary technique for systematic toxicological analysis procedures.

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A novel and simple procedure for concentrating adenoviruses from seawater samples is described. The technique entails the adsorption of viruses to pre-flocculated skimmed milk proteins, allowing the flocs to sediment by gravity, and dissolving the separated sediment in phosphate buffer. Concentrated virus may be detected by PCR techniques following nucleic acid extraction. The method requires no specialized equipment other than that usually available in routine public health laboratories, and due to its straightforwardness it allows the processing of a larger number of water samples simultaneously. The usefulness of the method was demonstrated in concentration of virus in multiple seawater samples during a survey of adenoviruses in coastal waters.

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Any transportation infrastructure system is inherently concerned with durability and performance issues. The proportioning and uniformity control of concrete mixtures are critical factors that directly affect the longevity and performance of the portland cement concrete pavement systems. At present, the only means available to monitor mix proportions of any given batch are to track batch tickets created at the batch plant. However, this does not take into account potential errors in loading materials into storage silos, calibration errors, and addition of water after dispatch. Therefore, there is a need for a rapid, cost-effective, and reliable field test that estimates the proportions of as-delivered concrete mixtures. In addition, performance based specifications will be more easily implemented if there is a way to readily demonstrate whether any given batch is similar to the proportions already accepted based on laboratory performance testing. The goal of the present research project is to investigate the potential use of a portable x-ray fluorescence (XRF) technique to assess the proportions of concrete mixtures as they are delivered. Tests were conducted on the raw materials, paste and mortar samples using a portable XRF device. There is a reasonable correlation between the actual and calculated mix proportions of the paste samples, but data on mortar samples was less reliable.