Electromagnetic Field Effect or Simply Stress? Effects of UMTS Exposure on Hippocampal Longterm Plasticity in the Context of Procedure Related Hormone Release

Harmful effects of electromagnetic fields (EMF) on cognitive and behavioural features of humans and rodents have been controversially discussed and raised persistent concern about adverse effects of EMF on general brain functions. In the present study we applied radio-frequency (RF) signals of the Universal Mobile Telecommunications System (UMTS) to full brain exposed male Wistar rats in order to elaborate putative influences on stress hormone release (corticosteron; CORT and adrenocorticotropic hormone; ACTH) and on hippocampal derived synaptic long-term plasticity (LTP) and depression (LTD) as electrophysiological hallmarks for memory storage and memory consolidation. Exposure was computer controlled providing blind conditions. Nominal brain-averaged specific absorption rates (SAR) as a measure of applied mass-related dissipated RF power were 0, 2, and 10 W/kg over a period of 120 min. Comparison of cage exposed animals revealed, regardless of EMF exposure, significantly increased CORT and ACTH levels which corresponded with generally decreased field potential slopes and amplitudes in hippocampal LTP and LTD. Animals following SAR exposure of 2 W/kg (averaged over the whole brain of 2.3 g tissue mass) did not differ from the sham-exposed group in LTP and LTD experiments. In contrast, a significant reduction in LTP and LTD was observed at the high power rate of SAR (10 W/kg). The results demonstrate that a rate of 2 W/kg displays no adverse impact on LTP and LTD, while 10 W/kg leads to significant effects on the electrophysiological parameters, which can be clearly distinguished from the stress derived background. Our findings suggest that UMTS exposure with SAR in the range of 2 W/kg is not harmful to critical markers for memory storage and memory consolidation, however, an influence of UMTS at high energy absorption rates (10 W/kg) cannot be excluded

Evidence for mantle exhumation along the Arabian margin in the Zagros (Kermanshah area, Iran)

The Kermanshah Crush Zone (Zagros, Iran) comprises elements from the Tethys Ocean and the former ocean-continent transition. Serpentinites and gabbros exposed in this area were formerly interpreted as originated from Tethys ocean and other residual Tethys oceanic domains all situated northeast of the Bisotoun platform. However, the structural relationships between these ultramafic units remained unclear. New field work in the Kermanshah-Harsin area led to the description of detachment faults over serpentinised mantle. ``Mid-Cretaceous'' carbonate ``extensional allochthons'' (pre-rift) and pelagic sediments (syn- to post-rift) dated from the Liassic are exposed above these detachments. Such an age mismatch can be explained by a polyphased mantle exhumation in a narrow basin along the Arabian margin with the assumption that no radiolarite nappe has been thrusted over the Bisotoun. Another detachment has been identified further to the NE on Eocene gabbro. So far, this one is considered as an intra-oceanic detachment from the residual Tethys. A first evolution model is proposed from early Jurassic to late Cretaceous obduction along with how this interpretation may be improved by future field work

Facies analyses, chronostratigraphy and paleoenvironemental reconstructions of jurassic to cetaceous sequence of the Congo basin

International audienceThe Congo Basin is characterized by an extensive and relatively thick (ca. 1 km) succession of Jurassic-Cretaceous sedimentary sequences that preserves a unique record of the tectonic and climatic evolution of central Africa during the main period of break-up of Gondwana and the emergence of the Indian and South Atlantic Oceans. New facies analysis and detailed correlations of these ‘Congo’ sequences are described from field observations in the southwestern Congo Basin and by re-logging cores and well logs from four deep boreholes drilled in the center of the basin in the 1950s and 1970s. The lowermost Upper Jurassic sequence (the Stanleyville Group) records a short marine incursion of the proto-Indian Ocean into the northern Congo Basin, and is in turn overlain to the south by widespread aeolian dune deposits (the Lower Kwango Group), which correlate well with other Upper Jurassic to Lower Cretaceous aeolian sequences in Namibia and eastern Brazil, attesting to a giant ‘Sahara-like’ paleo-desert across central West Gondwana, just before the separation of Africa from South America. U-Pb detrital zircons geochronology from this aeolian sequence in the Congo Basin dates mid-Silurian (ca. 430 Ma), Permian-Triassic (ca. 240 and 290 Ma) and Jurassic (ca. 190 Ma) magmatic zircons, here proposed to have been sourced from abundant volcanic activity along the proto-Andes, in southernmost Gondwana. Two successive middle Cretaceous lacustrine sequences in the center of the Congo Basin (the Loia and Bokungu Groups), first analcime-rich and episodically anoxic, and then more carbonated, are interpreted to record an episode of basin stagnation following the eruption of the Paraná-Etendeka Large Igneous Province and a subsequent hot/humid climate maximum during the opening of the South Atlantic Ocean. Late Cretaceous sedimentation in the Congo Basin terminated with fluvial sediments (the Upper Kwango Group) suggesting marginal uplifts during the Kalahari epeirogeny. The top of these sequences is truncated by a regional Cenozoic peneplanation surface

The diversity of Australian Mesozoic bennettitopsid reproductive organs

Several dispersed reproductive organs of bennettitopsid gymnosperms are described and illustrated from Triassic to Cretaceous strata of Australia: Williamsonia eskensis sp. nov. (Middle Triassic), Williamsonia ipsvicensis sp. nov. (Upper Triassic), Williamsonia durikaiensis sp. nov. (Lower Jurassic), Williamsonia sp. (Lower Jurassic), Williamsonia rugosa sp. nov. (Middle Jurassic), Williamsonia gracilis sp. nov. (Lower Cretaceous), Cycadolepis ferrugineus sp. nov. (Lower Jurassic), Cycadolepis sp. (Lower Cretaceous), and Fredlindia moretonensis Shirley 1898 comb. nov. (Upper Triassic). Among these, W. eskensis appears to represent the oldest bennettitalean reproductive structure yet identified. Although global floras expressed less provincialism during the Mesozoic and many genera are cosmopolitan, Australian bennettopsid species appear to have been endemic based on the morphological characters of the reproductive structures. Bennettopsids have a stratigraphic range of around 210 million years in Australia and are widely and abundantly represented by leaf fossils, but only around 20 specimens of reproductive structures, of which half are attributed to Fredlindia, have been recovered from that continent’s geological archive. The extremely low representation of reproductive organs vis-à-vis foliage is interpreted to reflect a combination of physical disintegration of the seed-bearing units while attached to the host axis and, potentially, extensive vegetative reproduction in bennettopsids growing at high southern latitudes during the Mesozoic.Other funding from:National Science Foundation (project #1636625)German Research Council (DFG KR2125/3)Friends of the Swedish Museum of Natural History (Riksmusei Vänner, Stockholm)SYNTHESYS (AT-TAF 467)</p