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Abstract: In this study, regulated and unregulated gaseous emissions and fuel consumption with five different fuels were tested in a 4-cylinder, light-duty diesel EURO IV typically used for the automotive vehicles in Europe. Three different biodiesel fuels obtained from soybean oil, rapeseed oil and palm oil, a Fischer Tropsch fuel and an ultra low sulphur diesel were studied. The test used was the New European Driving Cycle (NEDC), this allowed tests to be carried out on an engine warmed up beforehand to avoid the effect of cold starts and several tests a day. Regulated emissions of NOX, CO, HC and CO2 were measured for each fuel. Unburned Hydrocarbon Speciation and formaldehyde were also measured in order to determine the maximum incremental reactivity (MIR) of the gaseous emissions. Pollutants were measured without the diesel oxidation catalyst (DOC) to gather data about raw emissions. When biodiesel was used, increases in regulated and unregulated emissions were observed and also significant increases in engine fuel consumption. The use of Fischer Tropsch fuel, however, caused lower regulated and unregulated emissions and fuel consumption than diesel. [ABSTRACT FROM AUTHOR]

Abstract: Ragweed is one of the most important pollen allergens in North America and parts of Europe. Although the major allergen Amb a 1 was isolated and cloned in 1991, recombinant Amb a 1 was not explored further to improve diagnosis and specific immunotherapy of ragweed-pollen allergy. In the present study the immunological properties of natural Amb a 1 and its proteolytical cleavage products was investigated in detail and compared with recombinant produced Amb a 1 variants. Characterization of natural Amb a 1 and the identification of its proteolytic fragments, designated Amb a 1α and Amb a 1β, was performed by N-terminal sequencing and mass spectroscopy. Amb a 1 and fragments were further produced in Escherichia coli, purified, and immunologically characterized. Amb a 1-specific T-cell cultures were used to compare the T-cell response to the different Amb a 1 variants. Divergent immunological properties of Amb a 1α (aa 181–396) and Amb a 1β (aa 26–180) were revealed. Amb a 1β contained important IgE epitopes, whereas Amb a 1α showed low IgE binding. When compared to natural Amb a 1, all recombinant variants possessed >100-fold reduced IgE-mediated mediator release activity. At the T-cell level recombinant and natural Amb a 1 stimulated comparable T-cell responses and the T-cell reactivity was largely directed to the C-terminal part. The results demonstrated that recombinant Amb a 1α behaves as hypoallergen with reduced IgE binding but preservation of the major T-cell reactivity. In addition, recombinant Amb a 1α can be easily purified to homogeneity in large quantity and therefore represents an ideal candidate for specific immunotherapy. [Copyright &y& Elsevier]

Field and laboratory investigations of the exchange of the short-chain organic acids - formic acid and acetic acid - as well as their homologous aldehydes are discussed. Both acids are substantially released from several plant species. Emission measurements under field conditions are compiled to give an overview of three years of measurements. Emission rates from several tree species were found in the range between zero and 60 nmoles m-2 min-1 for acetic acid and between zero and 90 nmoles m-2 min-1 for formic acid though also a deposition has been observed to orange trees. Investigations under laboratory conditions showed an order of magnitude lower emission rates with significant differences under lightand dark conditions, and a deposition was observed under certain conditions. Hence, low emission rates or even a bi-directional exchange,emission as well as deposition have to be taken into account. Further differences between field and laboratory studies are discussed considering age of trees, stress effects and a potential production of acids by photochemical conversion of precursors inside enclosures during sampling. Field data on the exchange of form- and acetaldehyde showa complex behavior. We found emission as well as uptake. The bi-directional exchange is significantly triggered by the ambient mixing ratios of both aldehyde species and exhibits a compensation point. Further studies are needed for generalization of the exchange of these andpotentially also for other compounds. [ABSTRACT FROM AUTHOR]

This paper analyses the impact of the design of the UNECE Conventionon Long-Range Transboundary Air Pollution (CLRTAP) on the control oftransboundary air pollution in Europe. The history of CLTRAP is reviewed briefly: its origin as part of the East-West detente process of the 1970's has had considerable influence on its design. Germany's shift from environmental laggard to environmental leader in 1982 had a crucial impact on the effectiveness of the regime. Although transboundary air pollution in Europe has been reduced considerably, it is considered that the CLTRAP regime was only moderately effective in promoting this: much of it would have happened anyway. It has, however, been very effective in raising awareness of air pollution issues and providing a negotiating forum. [ABSTRACT FROM AUTHOR]

Digested sludge was applied to plowed arable and pasture grassland plots and losses of specific volatile organic compounds (VOCs), poly-chlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and chlorophenols (CPS) monitored over 260 d. Sludge addition increased soil concentrations of all compounds in the plowed plot. VOCs, PCBs, and Cps concentrations declined to control plot values within 128 d of sludge amendment. Volatilization and biodegradation were considered important loss processes for these compounds. However, PCDD/ F and of non-o-PCB 77 concentrations did not change consistently and remained elevated above controlplot concentrations throughout the monitoring period. At Day 260 410+/- 53 ng Sigma PCDD kg-1 and 250 - 10 ng Sigma PCDF kg-1 was detected in the sludged plot compared to 68 - 9 ng Sigma PCDD kg-1 and 170 - 7 ng Sigma PCDF kg-1 inthe control plot. Data from the pasture plot has highly variable anddifferences between most contaminant concentrations in the sludged and control plots were insignificant. This was attributed to adherenceof much of the applied sludge to vegetation rather than direct application to the soil surface and has important implications for elevated dietry intake of certain persistent organic compounds such as the PCDD/Fs. Further research is needed to evaluate the importance of sludge adherence to vegetation for human exposure to a range of contaminants detected in sludge. Contaminant movement to depth (20 cm) was notdetected within 260 d for compounds monitored (VOCs and PCDD/Fs). [ABSTRACT FROM AUTHOR]