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The rotation of magnetostrictive wires under excitation of an alternating axial magnetic field is a phenomenon discovered few years ago. Previous results and a recent mechanical experiment indicate that the appearance of these rotations is related to the sample vibrations associated to magnetoelastic resonance. This surprising behavior is here experimentally reported in polycrystalline FeNi levitating wires. An introductory analysis considering the balance of gravitational, magnetic gradient, and eddy-current forces is additionally carried out. Index Terms--Magnetic forces, magnetic levitation, magnetoelastic resonance, magnetostriction.

Aims: Little is known about the potential health impact of police encounters despite a ubiquitous police presence in many disadvantaged urban environments. In this paper, we assess whether persistent or aggressive interactions with the police are associated with poor mental health outcomes in a sample of primarily low-income communities of colour in Chicago. Methods: Between March 2015 and September 2016, we surveyed 1543 adults in ten diverse Chicago communities using a multistage probability design. The survey had over 350 questions on health and social factors, including police exposure and mental health status. We use sex-stratified logistic regression to examine associations between persistent police exposure (defined as a high number of lifetime police stops) or aggressive police exposure (defined as threat or use of police force during the respondent's most recent police stop) and the presence of post-traumatic stress disorder (PTSD) or depressive symptoms. Results: Men reporting a high number of lifetime police stops have three times greater odds of current PTSD symptoms compared with men who did not report high lifetime police stops (OR 3.1, 95% CI 1.3–7.6), after adjusting for respondent age, race/ethnicity, education, history of homelessness, prior diagnosis of PTSD and neighbourhood violent crime rate. Women reporting a high number of lifetime police stops have two times greater odds of current PTSD symptoms, although the results are not statistically significant after adjustment (OR 2.0, 95% CI 0.9–4.2). Neither persistent nor aggressive police exposure is significantly associated with current depressive symptoms in our sample. Conclusions: Our findings support existing preliminary evidence of an association between high lifetime police stops and PTSD symptoms. If future research can confirm as causal, these results have considerable public health implications given the frequent interaction between police and residents in disadvantaged communities in large urban areas. [ABSTRACT FROM AUTHOR]

Phytophthora infestans, the causal agent of late blight, threatens potato production worldwide. An important tool in the management of the disease is the use of resistant varieties. Eleven major resistance genes have been identified and introgressed from Solanum demissum. However, new sources of resistance are continually sought. Here, we report the characterization and refined genetic localization of a resistance gene previously identified as Rber in a backcross progeny of Solanum tuberosum and Solanum berthaultii. In order to further characterize Rber, we developed a set of P. infestans isolates capable of identifying each of the 11 R-genes known to confer resistance to late blight in potato. Our results indicate that Rber is a new resistance gene, different from those recognized in S. demissum, and therefore, it has been named R Pi-ber according to the current system of nomenclature. In order to add new molecular markers around R Pi-ber , we used a PCR-based mapping technique, named MASP-map, which located R Pi-ber in a 3.9 cM interval between markers CT240 and TG63 on potato chromosome X. The location of R Pi-ber coincides with an area involved in resistance to different pathogens of potato and tomato. [ABSTRACT FROM AUTHOR]