Felix J Hartmann

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Granulocyte-macrophage colony-stimulating factor (GM-CSF) has emerged as a crucial cytokine produced by auto-reactive T helper (Th) cells that initiate tissue inflammation. Multiple cell types can sense GM-CSF, but the identity of the pathogenic GM-CSF-responsive cells is unclear. By using conditional gene targeting, we systematically deleted the GM-CSF(More)
Genome-wide association studies implicate dysregulation of immune mechanisms in the pathogenesis of multiple sclerosis (MS). Particularly, polymorphisms in genes involved in T helper (TH) cell differentiation are associated with risk of developing MS. However, the underlying mechanism by which these risk alleles influence MS susceptibility has remained(More)
Ever since its invention half a century ago, flow cytometry has been a major tool for single-cell analysis, fueling advances in our understanding of a variety of complex cellular systems, in particular the immune system. The last decade has witnessed significant technical improvements in available cytometry platforms, such that more than 20 parameters can(More)
The neutron-to-proton density ratio at the nuclear periphery was determined for six targets from the yield of nuclei with mass (At21) generated by antiproton annihilation on targets with mass number At . A new setup allowed us to measure this yield for nuclei with half-lives down to 6 s. The experiment confirmed the negative correlation between the(More)
Narcolepsy type 1 is a devastating neurological sleep disorder resulting from the destruction of orexin-producing neurons in the central nervous system (CNS). Despite its striking association with the HLA-DQB1*06:02 allele, the autoimmune etiology of narcolepsy has remained largely hypothetical. Here, we compared peripheral mononucleated cells from(More)
The differences between neutron and proton density distributions at large nuclear radii in stable nuclei were determined. Two experimental methods were applied: nuclear spectroscopy analysis of the antiproton annihilation residues one mass unit lighter than the target mass and the measurements of strong-interaction effects on antiprotonic x rays. Assuming(More)
Autoimmune diseases like multiple sclerosis (MS) develop from the activation and complex interactions of a wide network of immune cells, which penetrate the central nervous system (CNS) and cause tissue damage and neurological deficits. Experimental autoimmune encephalomyelitis (EAE) is a model used to study various aspects of MS, including the infiltration(More)
We have measured the acceleration of neutrons by the material optical potential of solid 2H2. Using a gravitational spectrometer, we find a minimal kinetic energy Ec = (99+/-7) neV of neutrons from a superthermal ultracold neutron (UCN) source with solid 2H2 as an UCN converter. The result is in excellent agreement with theoretical predictions, Ec = 106 neV.
B. Ketzer,1 F. J. Hartmann,1 T. von Egidy,1 C. Maierl,1 R. Pohl,1 J. Eades,2 E. Widmann,2 T. Yamazaki,2 M. Kumakura,3 N. Morita,3 R. S. Hayano,4 M. Hori,4 T. Ishikawa,4 H. A. Torii,4 I. Sugai,5 and D. Horváth6 1Physik-Department, Technische Universität München, D-85747 Garching, Germany 2CERN, CH-1211 Geneva 23, Switzerland 3Institute for Molecular Science,(More)
X rays from the cascade of antiprotonic atoms have been studied by the PS209 Collaboration at LEAR of CERN. In this publication the strong interaction widths and shifts for calcium isotopes are presented. The isotopes Ca,Ca,Ca,Ca, and Ca have been investigated. The measured widths are compared with results from Hartree-Fock-Bogoliubov calculations. As a(More)