Marginal External Costs of Peak and Non Peak Urban Transport in Belgium

This paper discusses intermediate results of an ongoing research project to estimate all external costs from all transport modes in Belgium. It gives estimates of the marginal external costs of air pollution from urban transport. The evaluation of the environmental impacts is based on the European ExternE accounting framework. This methodology uses the impact pathway analysis for the detailed bottom-up assessment of impacts from air pollutants. It integrates state of the art knowledge in the fields of emission modelling, dispersion modelling, dose-response functions and monetary valuation. This paper focuses on the impact of location (rural areas versus cities), regulation, traffic conditions and congestion on environmental externalities. These case studies for Belgium confirm earlier results of the ExternE project that external environmental costs of car transport are significant and that damage to public health is the dominant impact. In addition, it shows that externalities of urban peak traffic are 2 to 4 times higher than for normal urban driving conditions. Finally, it calculates which occupancy rates are required for urban public transport (trams and diesel buses) to have lower external costs compared to passenger cars.Externalities, Urban transport, Air pollution, Congestion, Sustainable mobility

Coastal management and disaster planning on the basis of flood risk calculations

Recent studies showed that one third of the Belgian coastline is not sufficiently protected against severe storm events. Therefore coastal protection plans are set up to assure a minimum safety standard for the entire coastline. Flood risk calculations constitute the main input parameter for the concept and planning phases. Since 100% safety can never be guaranteed, contingency plans are constructed to reduce the remaining flood risks. Flood risk calculations are a powerful communicative and operational instrument to use between engineers and experts on the field, thus forming the link between coastal management and disaster planning

Die Weisen aus dem Wirtschaftsland?:Analyse der Zusammenarbeit von katholischen Diözesen und externen betriebswirtschaftlichen Strategieberatungen

Die Zusammenarbeit verschiedener Bistümer mit strategischen Unternehmensberatungen hat in den letzten Jahren für ein großes Medienecho gesorgt. Mit einer finanziellen Rechtfertigung wurden oftmals tiefe Veränderungen der pastoralen Landschaft beschlossen. Von vielen wurde die Angst geäußert, die Kirche entfremde sich mit den Wirtschaftsberatern von ihren Zielen, andere betonten die Notwendigkeit von soliden Finanzen. Mit dieser Studie werden die Zusammenarbeiten erstmals einer Analyse unterzogen. Durch Interviews mit Beteiligten der Beratungsprozesse und der Auswertung interner Dokumente konnte das Engagement der Berater in den Bistümern Aachen, Berlin, Essen, Köln, Mainz und Osnabrück untersucht werden. Dabei werden die jeweiligen Beratungsprozesse auf die Fragestellung untersucht, wie Theologie und Ökonomie in diesen Wandlungs- und Knappheitssituationen in Dialog gebracht werden konnten und wie nachhaltig die Ergebnisse waren - sowohl pastoral, als auch wirtschaftlich. <br/

When are bacteria dead? A step towards interpreting flow cytometry profiles after chlorine disinfection and membrane integrity staining

Flow cytometry is increasingly employed by drinking water providers. Its use with appropriate fluorescent stains allows the distinction between intact and membrane-damaged bacteria, which makes it ideally suited for assessment of disinfection efficiency. In contrast to plate counting, the technology allows the visualization of the gradual loss of membrane integrity. Although this sensitivity per se is very positive, it creates the problem of how this detailed viability information compares with binary plate counts where a colony is either formed or not. Guidelines are therefore needed to facilitate interpretation of flow cytometry results and to determine a degree of membrane damage where bacteria can be considered ‘dead’. In this study we subjected Escherichia coli and environmental microorganisms in real water to increasing chlorine concentrations. Resulting flow cytometric patterns after membrane integrity staining were compared with culturability and in part with redox activity. For laboratory-grown bacteria, culturability was lost at lower disinfectant concentrations than membrane integrity making the latter a conservative viability parameter. No recovery from chlorine was observed for four days. For real water, loss of membrane integrity had to be much more substantial to completely suppress colony formation, probably due to the heterogenic composition of the natural microbial community with different members having different susceptibilities to the disinfectant

Real-time detection of viable microorganisms by intracellular phototautomerism

BACKGROUND: To date, the detection of live microorganisms present in the environment or involved in infections is carried out by enumeration of colony forming units on agar plates, which is time consuming, laborious and limited to readily cultivable microorganisms. Although cultivation-independent methods are available, they involve multiple incubation steps and do mostly not discriminate between dead or live microorganisms. We present a novel generic method that is able to specifically monitor living microorganisms in a real-time manner. RESULTS: The developed method includes exposure of cells to a weak acid probe at low pH. The neutral probe rapidly permeates the membrane and enters the cytosol. In dead cells no signal is obtained, as the cytosolic pH reflects that of the acidic extracellular environment. In live cells with a neutral internal pH, the probe dissociates into a fluorescent phototautomeric anion. After reaching peak fluorescence, the population of live cells decays. This decay can be followed real-time as cell death coincides with intracellular acidification and return of the probe to its uncharged non-fluorescent state. The rise and decay of the fluorescence signal depends on the probe structure and appears discriminative for bacteria, fungi, and spores. We identified 13 unique probes, which can be applied in the real-time viability method described here. Under the experimental conditions used in a microplate reader, the reported method shows a detection limit of 10(6) bacteria ml(-1), while the frequently used LIVE/DEAD BacLight Syto9 and propidium iodide stains show detection down to 10(6) and 10(7) bacteria ml(-1), respectively. CONCLUSIONS: We present a novel fluorescence-based method for viability assessment, which is applicable to all bacteria and eukaryotic cell types tested so far. The RTV method will have a significant impact in many areas of applied microbiology including research on biocidal activity, improvement of preservation strategies and membrane permeation and stability. The assay allows for high-throughput applications and has great potential for rapid monitoring of microbial content in air, liquids or on surfaces