Usage of statistical modeling of lightning leader advancement process in the last stroke phase for determination of lightning protection system parameters

In the paper, the experimental data on the electrical physical characteristics of long spark gaps and lightning are used to create a lightning leader development model in the last stroke phase. The model is verified by comparison of the calculated probabilities of lightning attachments to air terminals and protected objects with normalized level. In order to determine the influence of ground system resistance on protection ability for lightning air terminals, lightning attachments with different ground system resistances have been modeled. The proposed method has been implemented for the calculation of lightning strokes probability to objects of an extended facility with oil storage tanks

Potential of Macrostomum lignano to recover from γ-ray irradiation

Stem cells are the only proliferating cells in flatworms and can be eliminated by irradiation with no damage to differentiated cells. We investigated the effect of fractionated irradiation schemes on Macrostomum lignano, namely, on survival, gene expression, morphology and regeneration. Proliferating cells were almost undetectable during the first week post-treatment. Cell proliferation and gene expression were restored within 1 month in a dose-dependent manner following exposure to up to 150 Gy irradiation. During recovery, stem cells did not cross the midline but were restricted within lateral compartments. An accumulated dose of 210 Gy resulted in a lethal phenotype. Our findings demonstrate that M. lignano represents a suitable model system for elucidating the effect of irradiation on the stem cell system in flatworms and for improving our understanding of the recovery potential of severely damaged stem-cell systems