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The rate of supernovae in our local Galactic neighbourhood within a distance of about 100 parsecs from Earth is estimated to be one every 2–4 million years, based on the total rate in the Milky Way (2.0 ± 0.7 per century). Recent massive-star and supernova activity in Earth’s vicinity may be traced by radionuclides with half-lives of up to 100 million years, if trapped in interstellar dust grains that penetrate the Solar System. One such radionuclide is 60Fe (with a half-life of 2.6 million years), which is ejected in supernova explosions and winds from massive stars. Here we report that the 60Fe signal observed previously in deep-sea crusts is global, extended in time and of interstellar origin from multiple events. We analysed deep-sea archives from all major oceans for 60Fe deposition via the accretion of interstellar dust particles. Our results reveal 60Fe interstellar influxes onto Earth at 1.5–3.2 million years ago and at 6.5–8.7 million years ago. The signal measured implies that a few per cent of fresh 60Fe was captured in dust and deposited on Earth. Our findings indicate multiple supernova and massive-star events during the last ten million years at distances of up to 100 parsecs.

The final pulse of the Variscan Orogeny in the northern Bohemian Massif (Saxo-Thuringian Zone) is related to the closure of the Rheic Ocean, which resulted in subduction-related D1-deformation followed by dextral strike-slip activity (D2-deformation, the Elbe Zone). Taken together, these deformation events reflect the amalgamation of Pangaea in central Europe. Lateral extrusion of high-grade metamorphosed rocks from an allochthonous domain (Saxonian Granulitgebirge) and the top–NW-directed transport of these domains (Erzgebirge nappe complex, Saxonian Granulitgebirge) are responsible for these dextral strike-slip movements. Geochronological data presented herein, together with published data, allow the timing of the final pulse of the Variscan Orogeny and related plutonic, volcano-sedimentary and tectonic processes. Marine sedimentation lasted at least until the Tournaisian (357 Ma). Onset of Variscan strike-slip along the Elbe Zone is assumed to be coeval with the beginning of the top–NW-directed lateral extrusion of the Saxonian Granulitgebirge at 342 Ma (D2-deformation). The sigmoidal shape of the Meissen Massif indicates that strike-slip activity was coexistent with intrusion of the pluton at c. 334 Ma into the schist belt of the Elbe Zone. In contrast, the intrusion of the Markersbach Granite provides a minimum age of c. 327 Ma for the termination of D2strike-slip activity, because this undeformed pluton cross-cuts all strike-slip related tectonic structures. Geochronological data of an ash bed from the Permo-Carboniferous Döhlen Basin show clearly that post-orogenic sedimentation of Variscan molasse in that area was already active at 305 Ma. This pull-apart basin is a local example of regional Permo-Carboniferous extension within Pangaea. The uplift and denudation of the Variscan basement in the Saxo-Thuringian Zone occurred between c. 327–305 Ma.

In the male rat the effects of portocaval shunt (PCS) on mineral metabolism (fractional intestinal absorption, minerals in serum, in bone, in kidney, and in urine) and the effects on urinary constituents were studied. PCS induced a degree of hyperparathyroidism and the formation of ammonium acid urate urinary tract stones. These phenomena were associated with elevated uric acid, ammonium, urinary pH, as well as with elevated supersaturation of urine with struvite, and to a lesser degree with ammonium acid urate. It is suggested that in the rat PCS interferes with both parathyroid gland function and urinary nucleation of ammonium acid urate.

The Precambrian of Germany mainly outcrops in the states of Saxony and Thuringia. The Proterozoic units are surrounded by the Palaeozoic of the Saxo-Thuringian, which is one of the Hercynian fold belts. In Thuringia, the sedimentary record from the Neoproterozoic to the Hercynian flysch stage (Lower Carboniferous) is nearly completely developed (Schwarzburg anticline). In contrast, Neoproterozoic sedimentation at least in two cases in Saxony was interrupted by the Cadomian orogenesis that was connected with the intrusion of 699-540 Ma old granodiorites. These Proterozoic complexes are foreign crustal fragments of a former, Cadomian consolidated orogenic belt enclosed in the Palaeozoic and must be classified as terranes (complexes I and II of the Lusatian terrane). The reconstruction of complex II is particulary complicated, because this part is separated into several parts by a dextral strike-slip fault cluster within the Elbe zone that was active during the uplift of the Hercynian orogen. Amphibolite- to granulite-grade metamorphic Precambrian units are probably par-autochthonous crustal derivates of the Hercynian basement (Ore Mountains anticline, Granulite Mountains anticline) and allochthonous Precambrian fragments enclosed in Hercynian nappes (Münchberg unit, Saxonian “Zwischengebirge”). The sedimentary rocks of the Proterozoic terranes and of the autochthonous Proterozoic of the Schwarzburg anticline enclosed in the Palaeozoic of the Saxo-Thuringian were deposited in submarine fans and consist of siliciclastics (predominantly greywackes, but also quartzite, pelitic siliciclastic rocks and other lithologies). The Weesenstein group, part of complex II of the Lusatian terrane, consists of proximal submarine fan-system deposits. The sedimentation regime was regulated by a rapid glacio-eustatically controlled fall of the sea level. By consideration of the glacio-eustatically influenced sedimentation, and by making use of new radiometric data, the sedimentary part of complex II of the Lusatian terrane (Weesenstein group and Clanzschwitz group) is dated as Cryogenian. The terrane-complex II is characterised as a splinter of an early Cadomian part of a former orogenic belt. The siliciclastics of the Leipzig group and the Lusatian group (complex I of the Lusatian terrane) were most probably deposited in Vendian time. The Lusatian terrane was a part of a late Cadomian fold belt. It therefore seems likely that the Cadomian consolidated terranes of Saxony were parts of peri-Gondwana.