The Effect of Water Boiled in Aluminum Cookwares on Genomic Abnormalities in the Meristematic Cells of Onion Root

Introduction: One of the ways of human exposure to aluminum (Al) is Al food packaging materials and cookwares. Although many studies have examined the biotic influence of nanoparticles or ionic form of heavy metals, there are limited studies conducted on the possible health risks of metals in the form of alloy used for making utensils. In this study, the effect of water boiled in Al cookwares with defined concentrations of Al on the genomic abnormalities and cell division of meristematic cells of onion root was evaluated using Allium cepa assay. Materials and Methods: The onion roots were treated with water boiled in Al utensils (three pots) with different concentrations of Al (5 and 10 mg/l) for 42 to 43 hours and then analyzed for mitotic index (MI) and mitotic phase aberrations (MPA). Results: The percent of MI in the study groups treated with 5 mg/l of Al from pot 1 and 10 mg/l from all pots increased significantly compared to the control group (P < 0.05). Also, the frequency of total MPA in all Al treated groups significantly increased compared to the control group (P < 0.05). The most significant results were derived by sticky chromosomes, anaphase bridge, going ahead chromosome and disturbed mitosis, respectively. Conclusion: The result of this study confirmed the genotoxic effect of water boiled in Al cookwares containing the examined range of Al concentrations on the meristematic cells of onion root.

INTRACAVITY LARGE-SCALE HETEROGENEITY AND THEIR INFLUENCE ON RADIATION PARAMETERS OF POWERFUL LASERS

Large‑scale inhomogeneities occur in the optical resonator of a high‑power laser due to uneven redistribution of heat and errors in the alignment of the circuit. Such inhomogeneities can significantly affect the characteristics of laser radiation. The paper analyzes the effect of large‑scale phase inhomogeneities associated with the separation and thermal deformation of unstable resonator mirrors on the parameters of the laser radiation – the power and angular divergence. The numerical simulation of the unstable resonator in the di‑fractional approximation is carried out, on the basis of which the quantitative effect of phase aberrations such as optical wedge (separation) and spherical lens (thermodeformation) on the power and divergence of laser radiation depending on the main characteristics of the unstable resonator‑the Fresnel number and the magnification coefficient is determined. The results of experimental studies of the effect of separation on the radiation parameters of a 100‑kilowatt CO2 gas‑dynamic laser are presented. The results of the work should be taken into account in the structural‑parametric optimization of the resonator.

Modeling of the 3D spatio-temporal thermal profile of joule-class -based laser amplifiers

Thermal profile modification of an active material in a laser amplifier via optical pumping results in a change in the material’s refractive index, and causes thermal expansion and stress, eventually leading to spatial phase aberrations, or even permanent material damage. For this purpose, knowledge of the 3D spatio-temporal thermal profile, which can currently only be retrieved via numerical simulations, is critical for joule-class laser amplifiers to reveal potentially dangerous thermal features within the pumped active materials. In this investigation, a detailed, spatio-temporal numerical simulation was constructed and tested for accuracy against surface thermal measurements of various end-pumped $\text{Yb}^{3+}$ -doped laser-active materials. The measurements and simulations show an excellent agreement and the model was successfully applied to a joule-class $\text{Yb}^{3+}$ -based amplifier currently operating in the POLARIS laser system at the Friedrich-Schiller-University and Helmholtz-Institute Jena in Germany.