Mn Zn ferrite films deposited on (100) MgO substrates by rf sputtering technique with different thicknesses ξ in the range of 30-450 nm were studied. AFM images show grain size increase as film thickness increases. Grains with diameters between L ∼ 70 and 700 nm were observed. The mono and multidomain regime in MnZn ferrite films and their effect on the pinning energy of domain walls are observed via Magneto-optical Kerr Effect, MOKE. At ξ ∼ 300 nm, the coercive field, H c , reaches a maximum value of 80 Oe. This result indicates the existence of a multidomain regime associated to a critical grain size, L c . We used the Jiles-Atherton model (JAM) to discuss the experimental hysteresis loops. The k pinning parameter obtained from JAM shows a maximum value of k/µ o = 67 Am 2 for grains with L c ∼ 529 nm. The total energy per unit area E was correlated with k and D. We found a simple phenomenological relationship given by E α kD; where D is the magnetic domain width.

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On a planet experiencing constant human population growth, it is necessary to explore the anthropogenic effects on the genetic diversity of species, and specifically invasive species. Using an analysis that integrates comparative phylogeography, urban landscape genetics, macrogenetics and a systematic review, we explore the worldwide genetic diversity of the human commensal and anthropogenic species Rattus rattus and Rattus norvegicus. Based on metadata obtained considering 35 selected studies related to observed heterozygosity, measured by nuclear molecular markers (microsatellites, Single Nucleotide Polymorphisms—SNPs-, restrictition site-associated DNA sequencing -RAD-Seq-), socioeconomic and mobility anthropogenic factors were used as predictors of genetic diversity of R. rattus and R. norvegicus, using the Gini index, principal component analysis and Random Forest Regression as analysis methodology. Population density was on average the best predictor of genetic diversity in the Rattus species analyzed, indicating that the species respond in a particular way to the characteristics present in urban environments because of a combination of life history characteristics and human-mediated migration and colonization processes. To create better management and control strategies for these rodents and their associated diseases, it is necessary to fill the existing information gap in urban landscape genetics studies with more metadata repositories, with emphasis on tropical and subtropical regions of the world.