Analysis of ethoxyquin residues in animal feed using QuEChERS and gas chromatography tandem mass spectrometry and its results from Catalonian production 2018-2019.

Ethoxyquin (EQ) is a quinolone commonly used as an antioxidant additive and a fungicide. However, Regulation (EU) 2017/962 suspended its authorisation as a feed additive for all animal species and categories. The aim of this study is thus to ensure compliance with this regulation by developing a method of analysing EQ in animal feed. For analysis, EQ was extracted from animal feed by using a modified QuEChERS protocol that used an ascorbic acid buffer to minimise its degradation. The extracts were analysed by gas chromatography coupled to triple quadrupole mass spectrometry (GC-QQQ), obtaining two chromatographic peaks corresponding to EQ and its transformation products. A study of these peaks was subsequently carried out using different standards, evincing that EQ had indeed been converted into several different transformation products. Quantification required the sum of the areas of the different peaks. The method was validated according to European Commission guidelines, namely SANTE/12682/2019. The obtainment of pesticide-free samples for carrying out the validation process was a critical achievement, as EQ residues were detected in 90% of the analysed samples. This was made possible by manufacturing 20 different feed samples from a mixture of several cereals used in animal feed in the laboratory. Method validation yielded excellent results in terms of accuracy (recoveries 70-120%), precision (RSD < 20%) and linearity (r2≥ 0.99) at the studied levels, as well as excellent sensitivity and selectivity (retention time ±0.1 min; ratio < 30%) to the LoQ. Over the course of 2018 and 2019, 70 samples of various feed matrices from agricultural production in Catalonia were analysed, garnering positive results 43% of the time.

Clinical usefulness of hemoencephalography beyond the neurofeedback.

AIM: Hemoencephalography (HEG) is an emerging procedure for clinical application in attention-deficit hyperactivity disorder and other disorders, regardless of age. It is available to any research group for its relative simplicity and low cost and is a useful tool for assessing prefrontal-dependent functions. Older teenagers pose peculiarities in the prefrontal maturation, and we aim to establish HEG patterns that might have clinical applicability. METHODS: The HEG patterns of 70 university students (56 women and 14 men, 21-48 years old, mean 31.84, SD 10.65, standard error of mean 0.31) were compared with those of 59 adolescents - 13-14-year-old secondary education students, 28 females and 31 males. The HEG patterns were obtained in response to the observation of shocking, unpleasant, and pleasant pictures. We use one-way and two-way analysis of variance to disentangle the differences between groups. All effects were analyzed with F-tests. RESULTS: In all cases, university students and adolescents showed a decrease in prefrontal activity, indicative of differences in the emotional inner networks between groups, which are responsible for security-insecurity processing. Compared with university students, adolescents showed statistically significant differences in decreased activity in very unpleasant (shocking) tests that demand increased security-insecurity processing. Adolescents showed lower decrease. In addition, adolescents, compared with university subjects, did not show statistically significantly decreased HEG activity compared with the baseline in very unpleasant tests. CONCLUSION: Teens showed distinguishable patterns of HEG, which were consistent with the cognitive emotional dysregulation in cognition and emotion interaction, that is, exterior network versus internal network interactions. Disability in regulation (modulation) of emotional response to negative emotional stimuli (fear of insecurity) in adolescence is an indicator of possible future clinical and psychiatric disorders such as depression and anxiety with high incidence of onset at this critical age and frequent comorbidity in attention-deficit hyperactivity disorder. HEG pattern might be a useful marker to define maturation and future possible mental dysfunctions.

Lenguaje y adopción internacional / Language and international adoption

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Photoassisted Electrochemical Treatment of Azo and Phtalocyanine Reactive Dyes in the Presence of Surfactants.

An electrochemical treatment (EC) was applied at different intensities to degrade the chromophoric groups of dyes C.I. Reactive Black 5 (RB5) and C.I. Reactive Blue 7 (Rb7) until uncolored species were obtained. Decolorization rate constants of the azo dye RB5 were higher than the phtalocyanine Rb7 ones. In addition, the EC treatment was more efficient at higher intensities, but these conditions significantly increased the generation of undesirable by-products such as chloroform. The combination of EC with UV irradiation (UVEC) drastically minimized the generation of chloroform. The photo-assisted electrochemical treatment was also able to achieve decolorization values of 99%. Finally, mixtures of dyes and surfactants were treated by EC and UVEC. In the presence of surfactants, the decolorization kinetic of dyes was slowed due to the competitive reactions of surfactants degradation. Both methods achieved total decolorization and in both cases, the generation of haloforms was negligible.

Photo-Electrochemical Treatment of Reactive Dyes in Wastewater and Reuse of the Effluent: Method Optimization.

In this work, the efficiency of a photo-electrochemical method to remove color in textile dyeing effluents is discussed. The decolorization of a synthetic effluent containing a bi-functional reactive dye was carried out by applying an electrochemical treatment at different intensities (2 A, 5 A and 10 A), followed by ultraviolet irradiation. The combination of both treatments was optimized. The final percentage of effluent decolorization, the reduction of halogenated organic volatile compound and the total organic carbon removal were the determinant factors in the selection of the best treatment conditions. The optimized method was applied to the treatment of nine simulated dyeing effluents prepared with different reactive dyes in order to compare the behavior of mono, bi, and tri-reactive dyes. Finally, the nine treated effluents were reused in new dyeing processes and the color differences (DECMC (2:1)) with respect to a reference were evaluated. The influence of the effluent organic matter removal on the color differences was also studied. The reuse of the treated effluents provides satisfactory dyeing results, and an important reduction in water consumption and salt discharge is achieved.