245 research outputs found
Zur Europäisierung des Verwaltungsrechts
 Die Europäisierung des Verwaltungsrechts ist ein fortschreitender, nicht endender Prozess. Betroffen sind Kernmaterien der innerstaatlichen Rechtsordnung wie etwa das Allgemeine Verwaltungsrecht, das Verwaltungsverfahrensrecht und das Verwaltungsprozessrecht. Der Beitrag analysiert die Einwirkungen des supranationalen Unionsrechts auf jene Rechtsgebiete und weist nach, dass das systematisch angelegte deutsche Verwaltungsrecht und die gut strukturierte Rechtsdogmatik in der Lage sind, die Europäisierung der innerstaatlichen Rechtsordnung zu bewältigen. Dabei zeigt sich, dass das Europarecht nicht nur Herausforderungen für das nationale Recht und das überkommene Rechtsdenken bereithält, sondern auch Impulse für die Modernisierung des deutschen Verwaltungsrechts setzt. 
Measurement of polarisation observables in photoproduction off the proton
The reaction is studied in the
photon energy range from threshold. Linearly polarised photon beams from
coherent bremsstrahlung enabled the first measurement of photon beam
asymmetries in this reaction up to MeV. In addition, the
recoil hyperon polarisation was determined through the asymmetry in the weak
decay up to MeV. The data are
compared to partial wave analyses, and the possible impact on the
interpretation of a recently observed cusp-like structure near the
thresholds is discussed.Comment: 6 pages, 5 figures. References [8,9,10,11] which were not on the
original submission are now include
Measurement of the Beam Asymmetry in the Forward Direction for pi0 Photoproduction
Photoproduction of neutral pions has been studied with the CBELSA/TAPS
detector for photon energies between 0.92 and 1.68~GeV at the electron
accelerator ELSA. The beam asymmetry~ has been extracted for of the ~meson and for . The new beam asymmetry data improve the world database for
photon energies above 1.5~GeV and, by covering the very forward region, extend
previously published data for the same reaction by our collaboration. The
angular dependence of shows overall good agreement with the SAID
parameterization.Comment: 11 pages, 10 figures, published in Phys. Rev. C, included LEPS data
and MAID 2007 predictions for comparison with our dat
Photoproduction of Neutral Pions off Protons
Photoproduction of neutral pions has been studied with the CBELSA/TAPS
detector in the reaction for photon energies between 0.85
and 2.50 GeV. The mesons are observed in their dominant neutral decay
mode: . For the first time, the differential cross
sections cover the very forward region, . A
partial-wave analysis of these data within the Bonn-Gatchina framework observes
the high-mass resonances (2190), (2080), and (2070).Comment: 12 pages, 9 figures, minor modifications to PWA sectio
Photoproduction of meson pairs: First measurement of the polarization observable I^s
The polarization observable I^s, a feature exclusive to the acoplanar
kinematics of multi-meson final states produced via linearly polarized photons,
has been measured for the first time. Results for the reaction g p -> p pi0 eta
are presented for incoming photon energies between 970 MeV and 1650 MeV along
with the beam asymmetry I^c. The comparably large asymmetries demonstrate a
high sensitivity of I^s to the dynamics of the reaction. Fits using
Bonn-Gatchina partial wave analysis demonstrate that the new polarization
observables carry significant information on the contributing partial waves.Comment: 11 pages, 6 figures, v2 to appear in Phys. Lett.
In-medium mass from the reaction
Data on the photoproduction of mesons on nuclei have been
re-analyzed in a search for in-medium modifications. The data were taken with
the Crystal Barrel(CB)/TAPS detector system at the ELSA accelerator facility in
Bonn. First results from the analysis of the data set were published by D.
Trnka et al. in Phys. Rev. Lett 94 (2005) 192303 \cite{david}, claiming a
lowering of the mass in the nuclear medium by 14 at normal nuclear
matter density. The extracted line shape was found to be sensitive to
the background subtraction. For this reason a re-analysis of the same data set
has been initiated and a new method has been developed to reduce the background
and to determine the shape and absolute magnitude of the background directly
from the data. Details of the re-analysis and of the background determination
are described. The signal on the target, extracted in the
re-analysis, does not show a deviation from the corresponding line shape on a
target, measured as reference. The earlier claim of an in-medium mass
shift is thus not confirmed. The sensitivity of the line shape to
different in-medium modification scenarios is discussed.Comment: 13 pages and 11 figures, submitted for publicatio
Quasi-free photoproduction of eta-mesons of the neutron
Quasi-free photoproduction of eta-mesons off nucleons bound in the deuteron
has been measured with the CBELSA/TAPS detector for incident photon energies up
to 2.5 GeV at the Bonn ELSA accelerator. The eta-mesons have been detected in
coincidence with recoil protons and recoil neutrons, which allows a detailed
comparison of the quasi-free n(gamma,eta)n and p(gamma,eta)p reactions. The
excitation function for eta-production off the neutron shows a pronounced
bump-like structure at W=1.68 GeV (E_g ~ 1 GeV), which is absent for the
proton.Comment: accepted for publication in Phys. Rev. Let
K^0 pi^0 Sigma^+ and K^*0 Sigma^+ photoproduction off the proton
The exclusive reactions and , leading to the p 4 final state, have
been measured with a tagged photon beam for incident energies from threshold up
to 2.5 GeV. The experiment has been performed at the tagged photon facility of
the ELSA accelerator (Bonn). The Crystal Barrel and TAPS detectors were
combined to a photon detector system of almost 4 geometrical acceptance.
Differential and total cross sections are reported. At energies close to the
threshold, a flat angular distribution has been observed for the reaction
suggesting dominant s-channel production.
and higher lying hyperon states have been observed. An
enhancement in the forward direction in the angular distributions of the
reaction indicates a -channel exchange
contribution to the reaction mechanism. The experimental data are in reasonable
agreement with recent theoretical predictions.Comment: 11 pages, 13 figures, submitted to EPJ
Determination of caspase-3 activation fails to predict chemosensitivity in primary acute myeloid leukemia blasts
BACKGROUND: Ex-vivo chemosensitivity tests that measure cell death induction may predict treatment outcome and, therefore, represent a powerful instrument for clinical decision making in cancer therapy. Such tests are, however, work intensive and, in the case of the DiSC-assay, require at least four days. Induction of apoptosis is the mode of action of anticancer drugs and should, therefore, result in the induction of caspase activation in cells targeted by anticancer therapy. METHODS: To determine, whether caspase activation can predict the chemosensitivity, we investigated enzyme activation of caspase-3, a key executioner caspase and correlated these data with chemosensitivity profiles of acute myeloid leukemia (AML) blasts. RESULTS: There was, however, no correlation between the ex-vivo chemosensitivity assessed by measuring the overall rates of cell death by use of the DiSC-assay and caspase-3 activation. CONCLUSION: Thus, despite a significant reduction of duration of the assay from four to one day, induction of apoptosis evaluated by capase-3 activity does not seem to be a valid surrogate marker for chemosensitivity
Linearly polarised photon beams at ELSA and measurement of the beam asymmetry in pi^0-photoproduction off the proton
At the electron accelerator ELSA a linearly polarised tagged photon beam is
produced by coherent bremsstrahlung off a diamond crystal. Orientation and
energy range of the linear polarisation can be deliberately chosen by accurate
positioning of the crystal with a goniometer. The degree of polarisation is
determined by the form of the scattered electron spectrum. Good agreement
between experiment and expectations on basis of the experimental conditions is
obtained. Polarisation degrees of P = 40% are typically achieved at half of the
primary electron energy. The determination of P is confirmed by measuring the
beam asymmetry, \Sigma, in pi^0 photoproduction and a comparison of the results
to independent measurements using laser backscattering.Comment: 9 pages, 10 figures, submitted to EPJ
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