136 resultados para Technological interaction


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The objectives of this work were to identify parents resistant to Asian soybean rust using diallel crosses, obtain information on the genetic control of soybean resistance to the pathogen and verify whether the combining ability estimates interact with the environment (year or time of assessment). The F1 generation was obtained in a greenhouse from crosses between five contrasting parents for the trait resistance to soybean rust, in a complete diallel without reciprocals. Two rust-severity assessments were carried out on individual soybean plants of 25 treatments (parents and F2 and F3 populations) in 2006/2007 and 2007/2008, in an experimental field at Embrapa Soja, Londrina, PR, Brazil. Additive effects predominated in the genetic control of soybean resistance to Asian rust, and the interaction of the segregant populations with the environment, although significant, did not alter the genetic parameter's general combining ability (GCA) and specific combining ability estimates, indicating that estimates obtained in one year and one assessment can be extrapolated to others. BR01-18437 inbred line is resistant to Asian rust and showed high GCA effects. This line should be used as parent if the objective is the resistance to Phakopsora pachyrhizi.

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The objective of this study was to assess genotype by environment interaction for seed yield per plant in rapeseed cultivars grown in Northern Serbia by the AMMI (additive main effects and multiplicative interaction) model. The study comprised 19 rapeseed genotypes, analyzed in seven years through field trials arranged in a randomized complete block design, with three replicates. Seed yield per plant of the tested cultivars varied from 1.82 to 19.47 g throughout the seven seasons, with an average of 7.41 g. In the variance analysis, 72.49% of the total yield variation was explained by environment, 7.71% by differences between genotypes, and 19.09% by genotype by environment interaction. On the biplot, cultivars with high yield genetic potential had positive correlation with the seasons with optimal growing conditions, while the cultivars with lower yield potential were correlated to the years with unfavorable conditions. Seed yield per plant is highly influenced by environmental factors, which indicates the adaptability of specific genotypes to specific seasons.

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The objective of this work was to evaluate an estimation system for rice yield in Brazil, based on simple agrometeorological models and on the technological level of production systems. This estimation system incorporates the conceptual basis proposed by Doorenbos & Kassam for potential and attainable yields with empirical adjusts for maximum yield and crop sensitivity to water deficit, considering five categories of rice yield. Rice yield was estimated from 2000/2001 to 2007/2008, and compared to IBGE yield data. Regression analyses between model estimates and data from IBGE surveys resulted in significant coefficients of determination, with less dispersion in the South than in the North and Northeast regions of the country. Index of model efficiency (E1') ranged from 0.01 in the lower yield classes to 0.45 in higher ones, and mean absolute error ranged from 58 to 250 kg ha‑1, respectively.

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In this work we report the obtention of a tetrabutylammonium hydroxide (TBAOH) solution in acetonitrile in a one pot process in order to study the interaction ironporphyrinOH- in non-aqueous systems. All the reactions were carried out under dry argon atmosphere to prevent the contamination of the solution with CO2, which leads to the formation of (TBA)2CO3.

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The interaction of mercury(II) with sulfathiazole has been analyzed. IR and NMR spectral studies suggest a coordination of Hg(II) with the Nthiazolic atom, unlike related Hg-sulfadrugs compounds. The complex was screened for its activity against Escherichia coli, showing an appreciable antimicrobial activity compared with the ligand.

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Potentiometric studies of sulfathiazole (HST) in the presence and absence of cobalt(II) were performed. Equilibrium constants for the formation of the detected species, [Co(ST)]+ and [Co(ST)(OH)], are reported. UV-Vis spectrophotometric measurements suggest that the coordination Co(II)-sulfathiazole might be through a N atom, which, in agreement with MO calculations, could be a thiazolic one. In spite of sulfonamides being better ligands at pH >7, [Co(ST)]+ was found at pH » 3.

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The electrochemical behavior of the interaction of amodiaquine with DNA on a carbon paste electrode was studied using voltametric techniques. In an acid medium, an electroactive adduct is formed when amodiaquine interacts with DNA. The anodic peak is dependent on pH, scan rate and the concentration of the pharmaceutical. Adduct formation is irreversible in nature, and preferentially occurs by interaction of the amodiaquine with the guanine group. Theoretical calculations for optimization of geometry, and DFT analyses and on the electrostatic potential map (EPM), were used in the investigation of adduct formation between amodiaquine and DNA.

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Mixed micellization and surface properties of cationic and nonionic surfactants dimethyl decyl-, tetradecyl- and hexadecyl phosphineoxide mixtures are studied using conductivity and surface tension measurements. The models of Rubingh, Rosen, and Clint, are used to obtain the interaction parameter, minimum area per molecule, mixed micelle composition, free energies of mixing and activity coefficients. The micellar mole fractions were always higher than ideal values indicating high contributions of cationics in mixed micelles. Activity coefficients were less than unity indicating synergism in micelles. The negative free energies of mixing showed the stability of the surfactants in the mixed micelles.

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Interaction and physicochemical characterization of dispersions of naproxen in calcium carbonate after freeze-drying the wet-state equilibrated mixture have been investigated by analytical methods. The FT-IR study revealed the acid-base reaction between naproxen and calcium carbonate. The DSC study indicated physical interaction and significantly diminished crystallinity of naproxen in the formulation containing higher quantities of calcium carbonate. Furthermore, the SEM study showed the reduced particle size and loss of crystalline morphology in the same sample. Drug release increased with the increase of calcium carbonate in the formulations. Formulation of naproxen with calcium carbonate in 1:2 ratio allowed its dissolution to the greatest extent (94.96%) while other compositions, 1:0.5 and 1:1, showed 80.86% and 78.30% release, respectively.

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In this work, a novel device based on polyacrylamide (PAAm) hydrogels and KL - DeOH - H2O lyotropic liquid crystal (LLC), with potential for application as Polymer Dispersed Liquid Crystals (PDLC), was proposed and its properties characterized. The confinement of LLC promoted significant changes in spectroscopic, morphological, optical, hydrophilic, structural and mechanical properties due to the interaction between the LLC-PAAm matrix and entropic parameter changes. The mechanical and structural properties can be controlled by adjusting AAm, temperature and presence of LLC, which can be useful for technological applications of these systems in optical devices.

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On the basis of theoretical B3LYP calculations, Yáñez and co-workers (J. Chem. Theory Comput. 2012, 8, 2293) illustrated that beryllium ions are capable of significantly modulating (changing) the electronic structures of imidazole. In this computational organic chemistry study, the interaction of this β-amino acid and five model Lewis acids (BeF1+, Be2+, AlF2(1+), AlF2+, and Al3+) were investigated. Several aspects were addressed: natural bond orbitals, including second order perturbation analysis of intra-molecular charge delocalization and the natural population analysis atomic charges; molecular geometries; selected infrared stretching frequencies (C-N, C-O, and N-H), and selected ¹H-NMR chemical shifts. The data illustrate that this interaction can weaken the H-O bond and goes beyond strengthening the intra-molecular hydrogen bond (N...H-O) to cause a spontaneous transfer of the proton to the nitrogen atom in five cases generating zwitterion structures. Many new features are observed. Most importantly, the zwitterion structures include a stabilizing hydrogen bond (N-H...O) that varies in relative strength according to the Lewis acid. These findings explain the experimental observations of α-amino acids (for example: J. Am. Chem. Soc. 2001, 123, 3577) and are the first reported fundamental electronic structure characterization of β-amino acids in zwitterion form.

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This work presents an electroanalytical method for the determination of moxifloxacin (MOXI) in tablets by its interaction with Cu(II) ion and subsequent electrochemical reduction at hanging mercury drop electrode (HMDE). A well-defined reduction peak at -0.21 V vs. Ag/AgCl in Phosphate buffer 0.04 mol L-1 pH 8.0 was observed for the complex reduction MOXI-Cu(II), using square-wave voltammetry (SWV). Using a 10 s of accumulation time at -0.40 V was found a limit detection of 3.60x10-8 mol l-1. The obtained results have shown good agreement with those obtained by spectrophotometric method.

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This work aimed to evaluate root colonization and interaction among isolates of rhizobacteria and eucalypt species. The method used to evaluate "in vitro" root colonization was able to indicate if the effect was benefic or deleterious allowing to pre-select isolates as potential growth promoter. There was interaction among isolates of rhizobacteria and Eucalyptus species for seed germinating and seedling growth. MF2 (Pseudomonas sp.) was the best rhizobacteria isolate for growth promotion of E. cloeziana e E. grandis. S1 (Bacillus subtilis) was the most effective for E. globulus, and Ca (Pseudomonas fulva), MF2 (Pseudomonas sp.), CIIb (Stenotrophomonas maltophilia) and S2 (B. subtilis) were the most promising isolates for the E. urophylla.

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ABSTRACT One of the fastest growing sectors in the domestic industry is the forestry, which has contributed significantly to economic development, job creation, income taxes, putting Brazil in a prominent position in the world market. This paper analyzes the evolution of the technological intensity of 12 main products exported by the sector, from 2000 to 2011. For that, utilizes an indicator called PRODY, which allows classifying different products according to their technological intensity or income content and considers the GDP per capita of exporting countries of each product, weighted by its revealed comparative advantage. It can be seen by the results, a continuous growth in all products' technology indicators and their decomposition into income effects, comparative advantage and joint effects, allowed to verify the main causes of this growth. Products with lower PRODY values are those that presented a higher evolution during the period studied. Products of higher processing, and those from pulp and paper industry, had greater technological advances, thanks to a joint effect, while the ones of lower processing, had a technological improvement due to the increase in GDP per capita in exporting countries. Sawn wood was the standout product, being the only one who proved to be dependent of comparative advantage effect, confirming that this industry has been reinventing itself and incorporating, in fact, more technology. This study revealed the importance of technological intensification to generate comparative advantage and be able to stand against international competition.

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ABSTRACT This study aimed to verify the differences in radiation intensity as a function of distinct relief exposure surfaces and to quantify these effects on the leaf area index (LAI) and other variables expressing eucalyptus forest productivity for simulations in a process-based growth model. The study was carried out at two contrasting edaphoclimatic locations in the Rio Doce basin in Minas Gerais, Brazil. Two stands with 32-year-old plantations were used, allocating fixed plots in locations with northern and southern exposure surfaces. The meteorological data were obtained from two automated weather stations located near the study sites. Solar radiation was corrected for terrain inclination and exposure surfaces, as it is measured based on the plane, perpendicularly to the vertical location. The LAI values collected in the field were used. For the comparative simulations in productivity variation, the mechanistic 3PG model was used, considering the relief exposure surfaces. It was verified that during most of the year, the southern surfaces showed lower availability of incident solar radiation, resulting in up to 66% losses, compared to the same surface considered plane, probably related to its geographical location and higher declivity. Higher values were obtained for the plantings located on the northern surface for the variables LAI, volume and mean annual wood increase, with this tendency being repeated in the 3PG model simulations.