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    New Fe II energy levels from stellar spectra

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    The spectra of B-type and early A-type stars show numerous unidentified lines in the whole optical range, especially in the 5100 - 5400 A interval. Because Fe II transitions to high energy levels should be observed in this region, we used semiempirical predicted wavelengths and gf-values of Fe II to identify unknown lines. Semiempirical line data for Fe II computed by Kurucz are used to synthesize the spectrum of the slow-rotating, Fe-overabundant CP star HR 6000. We determined a total of 109 new 4f levels for Fe II with energies ranging from 122324 cm^-1 to 128110 cm^-1. They belong to the Fe II subconfigurations 3d^6(^3P)4f (10 levels), 3d^6(^3H)4f (36 levels), 3d^6(^3F)4f (37 levels), and 3d^6(^3G)4f (26 levels). We also found 14 even levels from 4d (3 levels), 5d (7 levels), and 6d (4 levels) configurations. The new levels have allowed us to identify more than 50% of the previously unidentified lines of HR 6000 in the wavelength region 3800-8000 A. Tables listing the new energy levels are given in the paper; tables listing the spectral lines with loggf>/=-1.5 that are transitions to the 4f energy levels are given in the Online Material. These new levels produce 18000 lines throughout the spectrum from the ultraviolet to the infrared.Comment: Paper accepted by A&A for publicatio

    In vivo detection of lamellocytes in Drosophila melanogaster.

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    Drosophila has recently become a powerful model organism for studies of innate immunity. The cellular elements of innate immunity in Drosophila, the hemocytes, have been characterized by morphological criteria, molecular markers, and cell-type-specific immunological markers. Here we suggest that an MiET1 GFP-reporter element insertion in the untranslated region of a gene (l1-atilla) - expressed in a subset of hemocytes, the lamellocytes - allows in vivo investigations of lamellocyte differentiation and facilitates genetic screens
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