Abstract Vigorous training increases the production of reactive oxygen species (ROS) from skeletal muscle, which can contribute to impairing athletic performance and health. Mitochondrial antioxidant such as MitoQ may contribute to protecting against training-induced oxidative stress such as mitochondrial ROS, but the effects on athletic performance are unknown. The purpose of this study was to determine the effects of MitoQ to exercise training (EX) on VO2max, miRNA expression involved in inflammation and oxidative stress. In this double-blind clinical trial, 32 professional cyclists (25.6±3.8yr) were randomly divided into 4 groups (n=8); 1) Placebo, 2) EX (cycle ergometer, 75% of VO2max, 90 minutes, 3 sessions/week, and 4 weeks), 3) MitoQ (20 mg.day-1 for 4 weeks), and 4) EX+MitoQ (combined EX with MitoQ for 4 weeks). V˙O2max and gene expression of MicroRNAs (miRNAs)-19b, -181b, -155, and -146a and Serum levels of ROS (peroxides, superoxide, hydroxyl radical, singlet oxygen, and alpha oxygen), glutathione peroxidase (GPx), and superoxide dismutase (SOD) were measured by the gas analyzer, real-time polymerase chain reaction (2-ΔΔCt) and ELISA, respectively. Both EX+MitoQ and MitoQ reduced serum levels of ROS (P < 0.05), but there was no change in EX group. Serum GPx levels were increased in EX, MitoQ, and EX+MitoQ (P < 0.05), but there was no difference between groups. Serum SOD remained unchanged in all groups. miRNA-155 and miRNA-19b expressions were decreased in EX+MitoQ compared to EX, whereas miRNA-146a was increased in EX+MitoQ compared to EX (P < 0.05). Placebo-controlled intervention (tapioca powder) had no effects on all outcomes (P < 0.05). MitoQ supplementation and EX reduced ROS levels and altered expression of key miRNAs mediating ROS generation and vascular endothelial inflammation could contribute to improving vascular function.

Abstract Out of rachis and stem of palm tree from grooves in humid and dry zones, test materials were randomly collected and chipped for slow pyrolysis process. Chemical constituents of a set of pyrolysis derived vinegar were identified in their aqueous phase by gas chromatograph and quantitatively compared in sampled parts of sampled tree and grooves. Another set of vinegar was dewatered by dichloromethane, then their constituents were identified by gas chromatograph coupled with mass spectrometer, chemical constituents in aqueous state in both sampled grooves were the same but with different percentage values. In the organic phase, common chemical constituents of sampled parts and grooves were quantitatively compared. In humid zone rachis was 2,22 times richer in acetic acid and 2,37 times in phenol, but in dry zone stem is richer in acetic acid by 15,35 %. In their organic phases dominant and comparable chemicals of stem and rachis from sampled zone were furfural, phenol, benzic acid, 5-methyl-2- furancarboraldehyde, butanic acid and 2-methyl-phenol. Stem from dry zone was richer in these chemicals by 36,55 %; 96,93 %; 6,37 times, 62,05; 49; 32,57 % respectively. Rachis of humid zone contained more furfural, 63,95 %, 22,08 %, 2-methyl-phenol, but that of dry zone was richer in phenol by 46,20 %, 2,5 times in benzoic acid. Results from both phases of vinegar indicate that ecological impacts on the chemical constituents of palm from the same species are evident.

Lead is environmental pollutant that even in low trace is harmful for human health and wildlife. In this study we presented a colorimetric method for determination of Pb2+ in water by aggregation of silver nanoparticles capped citrate in the presence of deferoxamine as chelating agent. Silver nanoparticles were prepared by reduction of AgNO3 with NaBH4. In the presence of Pb2+, mixture of silver nanoparticles capped citrate and deferoxamine aggregated and color of solution changed from light yellow to violet that depends on Pb2+ concentration. As a result of aggregation, local surface plasmon resonance (LSPR) band of silver nanoparticles around 440 nm decreases and a new band appears at 580 nm that depend on Pb2+ concentration. Under optimized conditions, linear relation of concentration of Pb2+ and absorbance ratio (A580/A440), was from 0.19 to 1.29 µmol L-1 and limit of detection of 0.056 µmol L-1 was found. Control experiments with the addition of 10 other metal ions (Ni2+, Cu2+, Ca2+, Al3+, Co2+, K+, Ba2+, Zn2+, Mg2+, Hg2+) did not result in a distinct change in the color or in the absorption spectra. This approach was successfully tested for determination of Pb2+ in well and tap water.

A simple, inexpensive, reliable and environmentally friendly method based on ultrasound assisted extraction (UAE) combined with dispersive liquid-liquid microextraction with solidification of floating organic drop (DLLME-SFO) was developed for the simultaneous determination of four triazines in fruit and vegetable samples. Parameters affecting the extraction process were studied and optimized. Under the optimum conditions (sonication time: 15 min; extraction solvent: 30.0 µL 1-undecanol; disperser solvent: 1.0 mL acetonitrile; pH: 7; and extraction time: 0 min), extraction recoveries for different fruit and vegetables are in the range of 65-86%. The calibration graphs are linear in the range of 5-800 µg kg-1, with the correlation coefficient (r2) higher than 0.9985. The limits of detection (LODs) are in the range of 1-2 µg kg-1, which are lower than the maximum residue levels (MRLs) established by various official organizations. Repeatability (intra-day) and reproducibility (inter-day) of the method based on five replicate measurements of 100 µg kg-1 of herbicides were in the range of 3.6-5.4% and 4.5-6.3%, respectively.

Abstract The stress intensity factor (SIF) and the degree of bending (DoB) are among the crucial parameters in evaluating the fatigue reliability of offshore tubular joints based on the fracture mechanics (FM) approach. The value of SIF is a function of the crack size, nominal stress, and two modifying coefficients known as the crack shape factor (Yc) and geometric factor (Yg). The value of the DoB is mainly determined by the joint geometry. These three parameters exhibit considerable scatter which calls for greater emphasis in accurate determination of their governing probability distributions. As far as the authors are aware, no comprehensive research has been carried out on the probability distribution of the DoB and geometric and crack shape factors in tubular joints. What has been used so far as the probability distribution of these factors in the FM-based reliability analysis of offshore structures is mainly based on assumptions and limited observations, especially in terms of distribution parameters. In the present paper, results of parametric equations available for the computation of the DoB, Yc, and Yg have been used to propose probability distribution models for these parameters in tubular K-joints under balanced axial loads. Based on a parametric study, a set of samples were prepared for the DoB, Yc, and Yg; and the density histograms were generated for these samples using Freedman-Diaconis method. Ten different probability density functions (PDFs) were fitted to these histograms. The maximum likelihood (ML) method was used to determine the parameters of fitted distributions. In each case, Kolmogorov-Smirnov test was used to evaluate the goodness of fit. Finally, after substituting the values of estimated parameters for each distribution, a set of fully defined PDFs were proposed for the DoB, crack shape factor (Yc), and geometric factor (Yg) in tubular K-joints subjected to balanced axial loads.

A simple and sensitive on-line flow injection system for determination of zinc with FAAS has been described. The method is based on the separation and preconcentration of zinc on a microcolumn of immobilized Alizarin Red S on alumina. The adsorbed analyte is then eluted with 250 µL of nitric acid (1 mol L-1) and is transported to flame atomic absorption spectrometer for quantification. The effect of pH, sample and eluent flow rates and presence of various cations and anions on the retention of zinc was investigated. The sorption of zinc was quantitative in the pH range of 5.5-8.5. For a sample volume of 25 mL an enrichment factor of 144 and a detection limit (3S) of 0.2 µg L-1 was obtained. The precision (RSD, n=7) was 3.0% at the 20 µg L-1 level. The developed system was successfully applied to the determination of zinc in water samples, hair, urine and saliva.