Performance of the optimized Post-Zel'dovich approximation for CDM models in arbitrary FLRW cosmologies

We investigate the performance of the optimized Post-Zel'dovich approximation in three cold dark matter cosmologies. We consider two flat models with $\Omega_0=1$ (SCDM) and with $\Omega_0=0.3$ ($\Lambda$CDM) and an open model with $\Omega_0=0.3$ (OCDM). We find that the optimization scheme proposed by Wei{\ss}, Gottl\"ober & Buchert (1996), in which the performance of the Lagrangian perturbation theory was optimized only for the Einstein-de Sitter cosmology, shows the excellent performances not only for SCDM model but also for both OCDM and $\Lambda$CDM models. This universality of the excellent performance of the optimized Post-Zel'dovich approximation is explained by the fact that a relation between the Post-Zel'dovich order's growth factor $E(a)$ and Zel'dovich order's one $D(a)$, $E(a)/D^2(a)$, is insensitive to the background cosmologies.Comment: 8 pages, 3 figures, LaTex using aaspp4.sty and epsf.sty, Accepted for publication in ApJ Letter

The summertime Boreal forest field measurement intensive (HUMPPA-COPEC-2010): an overview of meteorological and chemical influences

This paper describes the background, instrumentation, goals, and the regional influences on the HUMPPA-COPEC intensive field measurement campaign, conducted at the Boreal forest research station SMEAR II (Station for Measuring Ecosystem-Atmosphere Relation) in Hyytiälä, Finland from 12 July–12 August 2010. The prevailing meteorological conditions during the campaign are examined and contrasted with those of the past six years. Back trajectory analyses show that meteorological conditions at the site in 2010 were characterized by a higher proportion of southerly flow than in the other years studied. As a result the summer of 2010 was anomalously warm and high in ozone making the campaign relevant for the analysis of possible future climates. A comprehensive land use analysis, provided on both 5 and 50 km scales, shows that the main vegetation types surrounding the site on both the regional and local scales are: coniferous forest (Scots pine and/or Norway spruce); mixed forest (Birch and conifers); and woodland scrub (e.g. Willows, Aspen); indicating that the campaign results can be taken as representative of the Boreal forest ecosystem. In addition to the influence of biogenic emissions, the measurement site was occasionally impacted by sources other than vegetation. Specific tracers have been used here to identify the time periods when such sources have impacted the site namely: biomass burning (acetonitrile and CO), urban anthropogenic pollution (pentane and SO<sub>2</sub>) and the nearby Korkeakoski sawmill (enantiomeric ratio of chiral monoterpenes). None of these sources dominated the study period, allowing the Boreal forest summertime emissions to be assessed and contrasted with various other source signatures

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Data expansion: the potential of grey literature for understanding floods

Sophisticated methods have been developed and become standard in analysing floods as well as for assessing flood risk. However, increasingly critique of the current standards and scientific practice can be found both in the flood hydrology community as well as in the risk community who argue that the considerable amount of information already available on natural disasters has not been adequately deployed and brought to effective use. We describe this phenomenon as a failure to synthesize knowledge that results from barriers and ignorance in awareness, use and management of the entire spectrum of relevant content, that is, data, information and knowledge. In this paper we argue that the scientific community in flood risk research ignores event-specific analysis and documentations as another source of data. We present results from a systematic search that includes an intensive study on sources and ways of information dissemination of flood-relevant publications. We obtain 186 documents that contain information on the sources, pathways, receptors and/or consequences for any of the 40 strongest trans-basin floods in Germany in the period 1952–2002. This study therefore provides the most comprehensive metadata collection of flood documentations for the considered geographical space and period. A total of 87.5% of all events have been documented, and especially the most severe floods have received extensive coverage. Only 30% of the material has been produced in the scientific/academic environment, and the majority of all documents (about 80%) can be considered grey literature (i.e. literature not controlled by commercial publishers). Therefore, ignoring grey sources in flood research also means ignoring the largest part of knowledge available on single flood events (in Germany). Further, the results of this study underpin the rapid changes in information dissemination of flood event literature over the last decade. We discuss the options and obstacles of incorporating this data into the knowledge-building process in light of the current technological developments and international, interdisciplinary debates for data curation

Efficiency of cytokine gene transfer in corneal endothelial cells and organ-cultured corneas mediated by liposomal vehicles and recombinant adenovirus

Purpose: Gene transfer of immunoregulatory cytokines could contribute to reduce rejection of corneal grafts. The aim of our study was to examine the gene transfer efficiency of liposomal vehicles compared to adenoviral vectors for transferring the Epstein-Barr-virus-derived interleukin 10 homologue (viral IL-10, vIL-10) into corneal endothelial cells and organ-cultured human corneas (HC) in vitro. Method: To test liposomal efficiency, 2 lipid formulations (SP-Chol/DOPE 20/80 and DDAB/DOPE 30/70 in various concentrations) were complexed with a plasmid containing the vIL-10 cDNA in an eukaryotic expression vector (pcDSRα-BCRF-I). The complexes were transferred to (1) subconfluent bovine corneal endothelial cells (BCEC) after 1 passage and to (2) HC stored in organ culture. In addition, BCEC and HC were transduced with the recombinant adenoviral vector encoding for vIL-10 (AdvIL-10). Secretion of vIL-10 in the supernatants from both transfected BCEC and HC was measured by specific ELISA. Results: For gene transfer in BCEC, both transfection methods (liposomes and adenovirus) led to high secretion of vIL-10 [>2 ng/ml (liposomes) and <150 ng/ml (adenovirus) per 5,000 initially planted BCEC]. Expression levels in BCEC were dependent on the concentration of applied liposomes. For gene transfer in HC, only the adenoviral transduction technique achieved a high production of vIL-10, whereas liposomal transfection led only to low vIL-10 secretion (4.8 μg/ml vs. 95 pg/ml per quarter of cornea). Conclusion: For transfection of corneal endothelial cells in culture, liposomes can be considered as a safe and useful alternative method of gene transfer avoiding side-effects of viral vectors. However, for transfection of organ-cultured HC, adenoviral vectors are superior to liposomal vehicles