57 research outputs found
Exposure to dissolved TNT causes multilevel biological effects in Baltic mussels (Mytilus spp.)
Highlights
• Shell closing as simple defence against acute toxicity of TNT.
• Mussels appear to be able to metabolize TNT to 2- and 4-ADNT.Biomarker responses occurred already at the lowest TNT exposure concentrations.
• Biomarker responses occurred already at the lowest TNT exposure concentrations.Baltic mussels (Mytilus spp.) were exposed to the explosive trinitrotoluene (TNT) for 96 h (0.31–10.0 mg/L) and 21 d (0.31–2.5 mg/L). Bioaccumulation of TNT and its degradation products (2- and 4-ADNT) as well as biological effects ranging from the gene and cellular levels to behaviour were investigated. Although no mortality occurred in the concentration range tested, uptake and metabolism of TNT and responses in antioxidant enzymes and histochemical biomarkers were observed already at the lowest concentrations. The characteristic shell closure behaviour of bivalves at trigger concentrations led to complex exposure patterns and non-linear responses to the exposure concentrations. Conclusively, exposure to TNT exerts biomarker reponses in mussels already at 0.31 mg/L while effects are recorded also after a prolonged exposure although no mortality occurs. Finally, more attention should be paid on shell closure of bivalves in exposure studies since it plays a marked role in definining toxicity threshold levels
North Sea Wrecks - An interdisciplinary approach towards understanding the risks posed by wrecks containing munitions in the North Sea
Shipwrecks and dumped munitions continue to be a major hazard in the North Sea. Research within the EU Interreg project North Sea Wrecks (NSW), in cooperation with DLR, is generating new insights into the status of wrecks, the potential leakage of pollutants from munitions loads and the effects of contamination on exposed marine organisms in the North Sea environment. Further, historical documents are compared to models and visual inspections of the wreck. Samples of water, sediment and organisms are being analysed. Combining the results of these different fields of research allows for a better understanding of the environmental risks deriving from these wrecks. The extended article will detail the wreck of the SMS Mainz as a case study
Long-range transport of airborne microbes over the global tropical and subtropical ocean
The atmosphere plays a fundamental role in the transport of microbes across the planet but it is often neglected as a microbial habitat. Although the ocean represents two thirds of the Earth’s surface, there is little information on the atmospheric microbial load over the open ocean. Here we provide a global estimate of microbial loads and air-sea exchanges over the tropical and subtropical oceans based on the data collected along the Malaspina 2010 Circumnavigation Expedition. Total loads of airborne prokaryotes and eukaryotes were estimated at 2.2 × 1021 and 2.1 × 1021 cells, respectively. Overall 33–68% of these microorganisms could be traced to a marine origin, being transported thousands of kilometres before re-entering the ocean. Moreover, our results show a substantial load of terrestrial microbes transported over the oceans, with abundances declining exponentially with
distance from land and indicate that islands may act as stepping stones facilitating the transoceanic transport of terrestrial microbes.En prens
The CMS Phase-1 pixel detector upgrade
The CMS detector at the CERN LHC features a silicon pixel detector as its innermost subdetector. The original CMS pixel detector has been replaced with an upgraded pixel system (CMS Phase-1 pixel detector) in the extended year-end technical stop of the LHC in 2016/2017. The upgraded CMS pixel detector is designed to cope with the higher instantaneous luminosities that have been achieved by the LHC after the upgrades to the accelerator during the first long shutdown in 2013–2014. Compared to the original pixel detector, the upgraded detector has a better tracking performance and lower mass with four barrel layers and three endcap disks on each side to provide hit coverage up to an absolute value of pseudorapidity of 2.5. This paper describes the design and construction of the CMS Phase-1 pixel detector as well as its performance from commissioning to early operation in collision data-taking.Peer reviewe
Alignment of the CMS tracker with LHC and cosmic ray data
© CERN 2014 for the benefit of the CMS collaboration, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl. Any further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation and DOI.The central component of the CMS detector is the largest silicon tracker ever built. The precise alignment of this complex device is a formidable challenge, and only achievable with a significant extension of the technologies routinely used for tracking detectors in the past. This article describes the full-scale alignment procedure as it is used during LHC operations. Among the specific features of the method are the simultaneous determination of up to 200 000 alignment parameters with tracks, the measurement of individual sensor curvature parameters, the control of systematic misalignment effects, and the implementation of the whole procedure in a multi-processor environment for high execution speed. Overall, the achieved statistical accuracy on the module alignment is found to be significantly better than 10μm
Indoor air particles in office buildings with suspected indoor air problems in the Helsinki area
Laboratory and model studies on the influence of biological aerosol particles on drop freezing
Untersuchung der Nukleationsfaehigkeit von biologischen Aerosolpartikeln mittels eines vertikalen Windkanals, einer Kondensationskammer und einer Depositions-Wachstumskammer Endbericht
SIGLEAvailable from TIB Hannover: F02B1782 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman
Cell Penetration, Herbicidal Activity, and in‐vivo‐Toxicity of Oligo‐Arginine Derivatives and of Novel Guanidinium‐Rich Compounds Derived from the Biopolymer Cyanophycin
ISSN:0018-019XISSN:1522-267
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