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Cereal Research Communications
Authors: V. Zecevic, D. Knezevic, J. Boskovic, D. Micanovic, and G. Dozet

A field experiment was conducted to investigate the effect of nitrogen fertilizer applications on some quality components of wheat. For winter wheat genotypes (Ana Morava, Vizija, L-3027 and Perla) were grown at Small Grains Research Centre Kragujevac in three years (2005–2007) at three levels of nitrogen fertilization (N 1 = 60 kg N ha −1 , N 2 = 90 kg N ha −1 and N 3 = 120 kg N ha −1 ). Zeleny sedimentation value and wet gluten content in divergent wheat genotypes were analyzed in depending on the nitrogen nutrition and years. Nitrogen fertilization significantly increased sedimentation value and wet gluten content. The highest increasing of both traits established in N 3 variant when applied 120 kg ha −1 of nitrogen. Genotypes reacted differently to N level increasing. Cultivar Perla had the highest value of sedimentation and wet gluten content and this cultivar the best reacted to increasing N levels. Statistically significant differences for sedimentation value and wet gluten content were found among cultivars, years, N-doses and for all their interactions. The results have shown that the best quality of wheat was with nitrogen applied of 120 kg N ha −1 . Correlation between nitrogen applications and sedimentation value was significant (r = 0.208*), while between N-doses and wet gluten content was high significant (r = 0.290**). Sedimentation value and wet gluten content positively correlated (r = 0.783**).

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Abstract  

The extraction of trivalent iron in the ionic and colloidal states from diluted nitric acid solutions with di-n-butylphosphoric acid in cyclohexane has been studied. Depending on the concentration of di-n-butylphosphoric and nitric acid, the ionic and colloidal trivalent iron can be distributed between the solvent, aqueous phase and solvent-aqueous interface.

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Recently secondary cattle selection traits have been given more attention in developed cattle breeding countries in establishing a selection index. In this way, milking traits have acquired a prominent place. This paper aimed to determine coefficients of correlation and regression between a number of milking traits, that could be helpful in establishing a selection index for breeding bulls and their dams. A further goal was to determine the distribution of milking parameters. The data of 303 Holstein Friesian and 235 Simmental cows were analysed.  The results showed that in both cow breeds correlations existed between milk yield and average milk flow (0.39 and 0.49), as well as between milk yield and milking time (0.53 and 0.35). Negative correlations were found between average milk flow and milking time (-0.49 and -0.56). For the Holstein Friesian breed, 67.0% of the cows had a total milk flow in the range of 1.61 to 3.60 kg/min, whereas in the Simmental breed 72.2% of the cows had a total milk flow of 2.40 kg/min.  The milk flow rate can be indirectly affected by selecting cows with higher milk production. The definition of an optimal milk flow rate and the determination of breeding goals for milking traits will lead to faster progress in milking trait improvement and an easier choice of quality breeding bulls and dams.

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Abstract

A new and rapid hydrophilic interaction liquid chromatographic method has been developed for the quantitative analysis of amlodipine besylate and its specific impurities (D, E, and F). For development of this method, a systematic approach which includes Design of Experiments methodology was applied. For the method optimization, Box–Behnken design and specific way Derringer's desirability function were applied. They provided identification of the optimal chromatographic conditions on the basis of obtained mathematical models and graphical procedures (three D graphs). The optimal chromatographic conditions were the analytical column ZORBAX NH2 (250 × 4.6 mm, 5 µm particle size); mobile phase consisted of acetonitrile-water phase (50 mM ammonium acetate, pH adjusted to 4.0 with glacial acetic acid) (90.5:9.5 v/v); column temperature 30 °C, mobile phase flow rate 1 mL min−1, wavelength of detection 230 nm. As other validation parameters were also found to be suitable, the possibility to apply the proposed method for the determination of amlodipine besylate and its impurities in any laboratory under different circumstances has been proven.

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Acta Biologica Hungarica
Authors: D. Đikić, Snježana Židovec-Lepej, Anica Remenar, Anica Horvat-Knežević, Vesna Benković, D. Lisičić, Lana Sajli, and O. Springer

Prometryne is a methylthio-s-triazine herbicide used to control annual broadleaf and grass weeds in many cultivated plants. Significant traces are documented in environment, mainly water, soil and plants used for human and domestic animal nutrition. Data on the toxic effects of prometryne and other methylthios-triazine have scorcely been published. The goal of this study was to investigate if prometryne, applied orally, could induce DNA damage in mouse leukocytes, in subchronical in vivo experimental design. Three different doses of prometryne were applied per os repeatedly every 48 hours. After the 7th dose (day 14) and the 14th dose (day 28) blood leucocytes were analyzed by alkaline Single Cell Gel Electrophoresis (Comet) assay. The results of three different comet parameters showed general increase in Olive tail moment, tail length and tail intensity values in treated groups of animals. The increase in measured values was almost proportional to the dose received and the time of exposure. We conclude that prometryne or its metabolic residues have the potential to induce processes that cause genotoxic effects on leukocytes on mice in in vivo repeated exposure.

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