Successful management of chemical sites: A challenge for management theory and practice:Comments on the article: “The future of German chemical sites: Potential pathways and organizational readiness.” by Clara Hiemer and Carsten Suntrop

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The offshore branch of the East African Rift System: crustal fabric across the Kerimbas Graben region

The Davie Fracture Zone (DFZ) evolved during the Jurassic and Cretaceous breakup and subsequent drift of Gondwana off East Africa. This old weak zone has been reactivated during the evolution of the East African Rift System. Recent faulting of Cenozoic sediments in the Kerimbas Basin off northern Mozambique shows that they are affected by the neotectonics. The question is if and howthe crustal fabric in our research area has been modified by the rifting process. We present two seismic refraction profiles acquired offshore northern Mozambique to investigate its regional crustal structure and tectonic history. The profiles show a continent– ocean transition zone that widens from around 40 km at 13◦S to more than 100 km at 11◦S. In the west the transitional crust is up to 12 km thick. To the east, around 150 km off the Mozambique coast lies oceanic crust whose thickness varies from 4.9 to 6.5 km along the northern line and from 6.5 to 7.5 km along the southern one. The latter presents an unusual high-velocity lower crustal body (7.0–7.2 km s−1), about 40 km wide and 3.8 km thick, underlying the oceanic crust. The body may consist of underplated melt with the same source as the nearby Paisley Seamount, which has not yet reached its isostatic equilibrium. Despite well documented recent seismicity along the margin, neither of the profiles reveal significant crustal modifications or reduced crustal seismic velocities that might be related to ongoing extensional tectonics as part of of the East African Rift System. Neither profile reveals seismic evidence for the presence of a major fracture zone or sheared continental margin parallel to the margin. Instead, the profiles’ broad continent–ocean transitions are consistent with their formation during an early Jurassic stage of plate divergence oblique to the margin. Later, after 157 Ma, the azimuth of relative plate motion between East andWest Gondwana changed to be parallel to the margin, and parts of the continent–ocean transitions may have been locally reactivated in a strike-slip sense. However, details on the plate movements during the directional change of the seafloor spreading between 157 and 144 Ma are not available. The oceanic crust formed by the initial divergent oblique extension became faulted/modified by the strike-slip movements between both plates. Instead of a narrow deformation zone, the DFZ is charcaterized by a broad, diffuse zone of transtensional deformation

Activation of Na+/Mg2+ antiport in thymocytes by cAMP

AbstractMg2+ efflux from Mg2+-loaded rat thymocytes was stimulated by 0.1 mM dibutyryl cAMP (db cAMP). The activation of Mg2+ efflux by db cAMP was more expressed at lower Mg2+-loading, cAMP induced only a very small increase in the concentration of intracellular free Mg2+ which cannot explain the activation of Na+/Mg2+ antiport. From these results it was concluded that cAMP increases the affinity of the Na+/Mg2+ antiporter for intracellular Mg2+, probably by phosphorylation

Crustal variability along the rifted/sheared East African margin

The East African margin between the Somali Basin in the north and the Natal Basin in the south formed as a result of the Jurassic/ Cretaceous dispersal of Gondwana. While the initial movements between East and West Gondwana left (oblique) rifted margins behind, the subsequent southward drift of East Gondwana from 157 Ma onwards created a major shear zone, the Davie Fracture Zone (DFZ), along East Africa. To document the structural variability of the DFZ, several deep seismic lines were acquired off northern Mozambique. The profiles clearly indicate the structural changes along the shear zone from an elevated continental block in the south (14°–20°S) to non-elevated basement covered by up to 6-km-thick sediments in the north (9°–13°S). Here, we compile the geological/geophysical knowledge of five profiles along East Africa and interpret them in the context of one of the latest kinematic reconstructions. A pre-rift position of the detached continental sliver of the Davie Ridge between Tanzania/ Kenya and southeastern Madagascar fits to this kinematic reconstruction without general changes of the rotation pole

Characterization of Mg2+ efflux from human, rat and chicken erythrocytes

AbstractNet Mg2+ efflux from Mg2+-loaded human, rat and chicken erythrocytes was measured in sucrose, NaCl and choline Cl medium. Thus, Na+-dependent (NaCl minus choline Cl) and Na+-independent Mg2+ efflux (in sucrose) were determined. Na+-dependent Mg2+ efflux amounted to 0.16, 8.9 and 1.57 mmol/l cells × 30 min, Na+-independent Mg2+ efflux amounted to 0.89, 1.55 and 0.37 mmol/l cells × 30 min for human, rat and chicken erythrocytes. Na+-dependent Mg2+ efflux was inhibited by quinidine. Na+-independent Mg2+ efflux was inhibited by SITS and Cl−. A small fraction of Na+-independent Mg2+ efflux (in choline Cl) was resistant to SITS and Cl−. Ca2+ loading increased Mg2+ efflux similar to K+ efflux (Gardos effect). This effect was differently expressed in human and chicken erythrocytes

Rotating system for four-dimensional transverse rms-emittance measurements

Knowledge of the transverse four-dimensional beam rms-parameters is essential for applications that involve lattice elements that couple the two transverse degrees of freedom (planes). Of special interest is the removal of inter-plane correlations to reduce the projected emittances. A dedicated ROtating System for Emittance measurements (ROSE) has been proposed, developed, and successfully commissioned to fully determine the four-dimensional beam matrix. This device has been used at the High Charge injector (HLI) at GSI using a beam line which is composed of a skew quadrupole triplet, a normal quadrupole doublet, and ROSE. Mathematical algorithms, measurements, and results for ion beams of 83Kr13+ at 1.4 MeV/u are reported in this paper.Comment: 11 pages, 10 figure

Foetal and Maternal Magnesium Metabolism: Effect of Magnesium Deficiency and Isoproterenol

Peer Reviewe

Bewertung von Pflanzenbeständen und Milchleistung in Ökobetrieben Nordwestdeutschlands

In order to produce high quality forages, the species composition of the grass sward is of special importance. A good measure for estimating the quality of grass swards is the so-called mean Futterwertzahl of the sward by Klapp (1965) which is further referred to as Sward Quality Index (SQI). On 56 organic farms the average SQI of the farm has been calculated and the yield proportion of different species of the sward has been calculated for different regions of Northwest Germany. Within 22 organic farms with grassland farming exclusively, a comparison of the milk yields (kg ECM/cow and year) and the mean SQI of the grassland has been calculated with special regard to the concentrate rates fed to the cows. In tendency the results show lower SQI in farms with lower milk yields in comparison to farms with higher SQI. However, the evaluations show high variations, indicating, that other factors (management, animal health problems, cutting dates and forage quality factors) might have influenced the result

Kraftfuttergaben und Milchleistung bei Weidegang von Milchviehherden im ökologischen Landbau

During grazing, the efficiency of concentrate feeding on milk yields is low, especially when white clover is present in the sward (Wilkens et al., 1994). Clover in animal feed enhances forage intake; feeding trials have shown increased intake rates by 15-30 % (Paul, 2003). These results are of special interest for organic farms, where clover has a higher impact on the farming system. In the experimental organic farm of the Landwirtschaftskammer Nordrhein-Westfalen (Haus Riswick) the concentrate rate fed during grazing time showed no influence upon milk yields (2,6 resp.4,7 kg DM concentrate/ animal/day). In agreement with these results a three years investigation on 89 organic farms in Northwest Germany showed no effect of concentrate feeding on milk yield during the grazing season. Furthermore, a reduction or increase of concentrate rates during the grazing season did not show any differences in animal health so far