Wie die nordischen Götter und Helden bis heute fortleben : ein Blick in die Edda-Sammlung des Instituts für Skandinavistik

Edda – diesen Namen tragen zwei isländische Werke aus dem 13. Jahrhundert. Gemeinsam überliefern sie, das eine in Liedern, das andere in Prosa, den größten erhaltenen Schatz an nordischer Mythologie und Heldensage. Gern für »germanisch« gehalten sind diese Stoffe seit dem 18. Jahrhundert weit über Island hinaus bekannt. Das spiegelt sich auch in den mehr als 1200 Objekten der Frankfurter Edda-Sammlung, die zeigen, wie die Mythen buchstäblich in jeden Winkel der Kultur vordringen können

African swine fever in wild boar: evaluation of its epidemiology, surveillance and control integrating participatory epidemiology.

African swine fever (ASF) has been a concern for 100 years. However, after the disease reached Georgia in 2007 and spread rapidly, researchers worldwide became even more interested. The role of wild boar in the current epidemic is prominent. The epidemiology of ASF in wild boar was therefore examined in detail and existing knowledge gaps closed. The enclosed participatory studies with hunters helped to identify starting points whose inclusion could help to improve ASF surveillance, make it more effective and thus increase the chance of its successful application.Die Afrikanische Schweinepest (ASP) ist bereits seit 100 Jahren ein Problem. Nachdem die Seuche 2007 Georgien erreichte und sich rasch ausbreitete, wurde das Interesse der Forscher weltweit noch größer. Die Rolle der Wildschweine bei der aktuellen Epidemie ist von großer Bedeutung. Die Epidemiologie der ASP bei Wildschweinen wurde eingehend untersucht und bestehende Wissenslücken geschlossen. Partizipative Studien mit Jägern halfen, Ansatzpunkte zu identifizieren, um die ASP-Überwachung zu verbessern, sie effektiver zu gestalten und damit die Chance auf eine erfolgreiche Anwendung zu erhöhen

"Can we agree on that"? Plurality, power and language in participatory research

Participatory epidemiology (PE) is a method that gathers data from groups through focus group interviews and participatory visual and scoring exercises. The method is often used in poor communities in low-income countries where it is hard to obtain conventional epidemiological data. This paper draws on research on the public sphere and democratic deliberation, along with research on language and interpretation, to suggest how PE research could be better equipped to account for diversity in local knowledge, include minority views and acknowledge power dynamics. These aspects are discussed under the three themes of 'plurality', 'power' and 'language'. A review of highly-cited PE literature suggests that PE research engages with plurality and power to a very limited extent, and only marginally more so with language and translation. Examples are taken from the authors' own PE research on African swine fever in -Uganda, classical swine fever in Germany, peste des petits ruminants (PPR) in Eastern Europe, and Ugandan pastoralists' understanding of cattle disease to provide more detail as to why conventional PE studies might fail to record issues of plurality, power and language, and also to suggest how this can be addressed. With reference to the literature on the public sphere and democratic deliberation, and on language and interpretation, this paper concludes with some suggestions as to how to take plurality, power and language into greater consideration in PE studies in future, thus improving the validity and reliability of PE data

Spectroscopy of the stellar wind in the Cygnus X-1 system

The X-ray luminosity of black holes is produced through the accretion of material from their companion stars. Depending on the mass of the donor star, accretion of the material falling onto the black hole through the inner Lagrange point of the system or accretion by the strong stellar wind can occur. Cygnus X-1 is a high mass X-ray binary system, where the black hole is powered by accretion of the stellar wind of its supergiant companion star HDE226868. As the companion is close to filling its Roche lobe, the wind is not symmetric, but strongly focused towards the black hole. Chandra-HETGS observations allow for an investigation of this focused stellar wind, which is essential to understand the physics of the accretion flow. We compare observations at the distinct orbital phases of 0.0, 0.2, 0.5 and 0.75. These correspond to different lines of sights towards the source, allowing us to probe the structure and the dynamics of the wind.Comment: conference proceeding from Integral/Bart Workshop Karlsbad, CZ, 14.4-18.4 201

Chandra X-ray spectroscopy of the focused wind in the Cygnus X-1 system. I. The non-dip spectrum in the low/hard state

We present analyses of a 50 ks observation of the supergiant X-ray binary system Cygnus X-1/HDE 226868 taken with the Chandra High Energy Transmission Grating Spectrometer (HETGS). Cyg X-1 was in its spectrally hard state and the observation was performed during superior conjunction of the black hole, allowing for the spectroscopic analysis of the accreted stellar wind along the line of sight. A significant part of the observation covers X-ray dips as commonly observed for Cyg X-1 at this orbital phase, however, here we only analyze the high count rate non-dip spectrum. The full 0.5-10 keV continuum can be described by a single model consisting of a disk, a narrow and a relativistically broadened Fe Kalpha line, and a power law component, which is consistent with simultaneous RXTE broad band data. We detect absorption edges from overabundant neutral O, Ne and Fe, and absorption line series from highly ionized ions and infer column densities and Doppler shifts. With emission lines of He-like Mg XI, we detect two plasma components with velocities and densities consistent with the base of the spherical wind and a focused wind. A simple simulation of the photoionization zone suggests that large parts of the spherical wind outside of the focused stream are completely ionized, which is consistent with the low velocities (<200 km/s) observed in the absorption lines, as the position of absorbers in a spherical wind at low projected velocity is well constrained. Our observations provide input for models that couple the wind activity of HDE 226868 to the properties of the accretion flow onto the black hole.Comment: 16 pages, 15 figures, uses emulateapj, published as ApJ 690:330-346, 2009 January

Multi-Satellite Observations of Cygnus X-1 to Study the Focused Wind and Absorption Dips

High-mass X-ray binary systems are powered by the stellar wind of their donor stars. The X-ray state of Cygnus X-1 is correlated with the properties of the wind which defines the environment of mass accretion. Chandra-HETGS observations close to orbital phase 0 allow for an analysis of the photoionzed stellar wind at high resolution, but because of the strong variability due to soft X-ray absorption dips, simultaneous multi-satellite observations are required to track and understand the continuum, too. Besides an earlier joint Chandra and RXTE observation, we present first results from a recent campaign which represents the best broad-band spectrum of Cyg X-1 ever achieved: On 2008 April 18/19 we observed this source with XMM-Newton, Chandra, Suzaku, RXTE, INTEGRAL, Swift, and AGILE in X- and gamma-rays, as well as with VLA in the radio. After superior conjunction of the black hole, we detect soft X-ray absorption dips likely due to clumps in the focused wind covering >95 % of the X-ray source, with column densities likely to be of several 10^23 cm^-2, which also affect photon energies above 20 keV via Compton scattering.Comment: 10 pages, contributed talk at the 7th Microquasar Workshop, Foca, Turkey, Sept. 1-5, 200

Identifying and understanding long-distance travel demand by combining official transport statistics and survey data

While much is known about everyday travel of the German population, long-distance travel is still underreported. The main data source, the national travel survey “Mobility in Germany (MiD)”, cannot simply be used to describe the demand: complex extrapolations and complementary data are necessary to obtain a consistent picture. The presented approach of ‘data fusion’ integrates different data sources to provide the overall long-distance travel demand. The result reveals that almost half of the total transport performance of the residential population in Germany (46 % of passenger kilometers) is accounted for by trips of at least 100 km (one-way distance)

Suzaku Observations of 4U 1957+11: Potentially the Most Rapidly Spinning Black Hole in (the Halo of) the Galaxy

We present three Suzaku observations of the black hole candidate 4U 1957+11 (V1408 Aql) --- a source that exhibits some of the simplest and cleanest examples of soft, disk-dominated spectra. 4U 1957+11 also presents among the highest peak temperatures found from disk-dominated spectra. Such temperatures may be associated with rapid black hole spin. The 4U 1957+11 spectra also require a very low normalization, which can be explained by a combination of small inner disk radius and a large distance (>10 kpc) which places 4U 1957+11 well into the Galactic halo. We perform joint fits to the Suzaku spectra with both relativistic and Comptonized disk models. Assuming a low mass black hole and the nearest distance (3 M_sun, 10 kpc), the dimensionless spin parameter a* = Jc/GM^2 >~ 0.9. Higher masses and farther distances yield a*~1. Similar conclusions are reached with Comptonization models; they imply a combination of small inner disk radii (or, equivalently, rapid spin) and large distance. Low spin cannot be recovered unless 4U 1957+11 is a low mass black hole that is at the unusually large distance of >~ 40 kpc. We speculate whether the suggested maximal spin is related to how the system came to reside in the halo.Comment: To be published in the Astrophysical Journa