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ln order to provide a quantitative basis for pretreatment and therapy of intoxications with sulfur mustard the toxicokinetics of this agent as well as its major DNA-adducts are being studied in male hairless guinea pigs for the intravenous, respiratory and percutaneous routes. A highly sensitive method for bioanalysis of the intact agent in blood and tissues was developed, involving gas chromatography with automated thermodesorption injection and mass-spectrometric detection. Deuterated sulfur mustard is used as the internal standard. The absolute detection limit is 700 fg for sulfur mustard, which corresponds with a detection limit in blood of ca. 5 pg/ml. DNA-adducts are measured via the previously developed immuno-slot-blot method, using antibodies directed against the adduct of sulfur mustard to guanine. The intravenous 96-h LD50 of sulfur mustard in the hairless guinea pig was determined and appeared to be 8.2 mg/kg. The intravenous toxicokinetics of this dose in the hairless guinea pig are characterized by a very rapid distribution phase and a very slow elimination phase. A rapid adduct formation occurs in blood and lung, and subsequently in other organs. The adduct levels in lung were remarkably high. A considerable repair of the adducts is observed within 6 h. However, at 2 days after administration of sulfur mustard adducts are still detectable in most of the organs studied. The intravenous toxicokinetics of sulfur mustard were also studied in the marmoset at a dose corresponding with 1 LD50 in the hairless guinea pig. The results obtained sofar will be discussed.

Maintenance and operations of road safety equipment and infrastructure ensure that all safety related elements of the road system are operating as they were designed, tested, and approved. Maintenance of road equipment should not only be considered as the repair of broken or damaged equipment, but also as a potential monitoring system for the road network. This overlooked aspect of maintenance and operations is a central theme for the following sections.

An algorithm for the retrieval of the aerosol optical thickness over land and over water from Global Ozone Monitoring Experiment (GOME) data is presented. The cloud fraction in the GOME pixels is determined using the Fast Retrieval Scheme for Clouds From the Oxygen A Band (FRESCO) algorithm. Surface contributions to the top of atmosphere reflectance are determined from the GOME surface reflectance database. The aerosol retrieval algorithm uses lookup tables that were created using the radiative transfer model 6S. The algorithm allows retrieving the aerosol types characterized by Angstrom coefficients in the range from -0.1 to 2.8; i.e., the range of values observed by the AERONET ground-based measurements. Validation of the algorithm done using the AERONET Sun photometer data for 12 sites in Europe and Africa, for the year 1997, shows very good agreement. The correlation coefficient between the satellite retrieval and AERONET data for the wavelength of 440 nm is 97%, and for 670 nm it is 94%. Validation of the algorithm for the year 2000 was done for a few sites with similar results. The algorithm has been successfully tested over an island influenced by Saharan dust (i.e., Cape Verde, 16oN, 22oW and over a site located near the Saharan desert (i.e., Bondoukoui, 11oN, 3oW). For other sites located near the Saharan desert such as Bidi Bahn (14oN, 2oW) and Banizombou (13oN, 2oE), the agreement was very good at 440 nm. The algorithm has not been tested over other bright surfaces such as ice-covered regions. Examples of the spatial distribution of the aerosol optical thickness over Europe, north Africa, and the North Atlantic for the year 1997 and 2000 are presented.

The European Commission Directorate General for Transportation and Energy (DGTREN) sponsored a research project to investigate the best practice guidelines for roadside infrastructure. The RISER consortium has compiled the following document which is a synthesis of existing practice in Europe with additional information collected from accident and human behaviour studies. Several technical reports developed in the RISER project were the basis for this document and can provide more technical information. The information contained in this document should be used in conjunction with the document 'European Best Practice for Roadside Design: Guidelines for Maintenance and Operations of Roadside Infrastructure'.

Chemical analysis is one of the most important parts within an energetic material lifecycle. It starts with the qualification and quantification of the raw materials and/or the intermediate materials used for the manufacturing of the final product. When the product is finished there is quality control and finally after functioning or demilitarisation components will end-up in the environment.

Laboratory experiments have been carried out to elucidate the role of surfactants on the primary marine aerosol production of submicron marine aerosols. A synthetic surfactant SDS was used in conjunction with artificially generated seawater, and the resultant bubble-mediated aerosol produced was observed. At 23°C, the aerosol distribution resulting from the use of surfactant-free seawater comprised three modes: (1) a dominant accumulation mode at 110 nm; (2) an Aitken mode at 45 nm; and (3) a third mode, at 300 nm, resulting from forced bursting of bubbles. The forced bursting occurs when bubbles fail to burst upon reaching the surface and are later shattered by splashing associated with breaking waves and/or wind pressure at the surface. At 4°C, the accumulation mode diameter was reduced to 85 nm, the Aitken mode diameter was reduced to <30 nm and the 300 nm mode diameter was reduced to 200 nm. With the addition of SDS, the relative importance of the mode resulting from forced bursting increased dramatically. The laboratory results were compared to the observed seasonality of North Atlantic marine aerosol where a progression from mode radii minima in winter to maxima in summer is seen. The bimodality and the seasonality in modal diameter can be mostly explained by a combination of the three modes observed in the laboratory and their variation as a function of sea-surface temperature and seawater surfactant concentration. These results indicate that submicron primary aerosol modes would on a first approximation result from bubble bursting processes, although evidences of additional secondary processes leading, during summer, to a higher amplitude of the Aitken mode and mode 2 smoothed into mode 3 still need to be investigated. Copyright 2006 by the American Geophysical Union.

We present a generic mass spectrometric method to verify exposure to organophosphates, based on the chemical conversion of the phosphylated peptides obtained after pepsin digestion of human butyrylcholinesterase (HuBuChE) to a common precursor peptide. After exposure of plasma to various organophosphates (nerve agents, pesticides), HuBuChE was isolated from plasma by procainamide affinity-based solid-phase extraction. Upon subsequent pepsin digestion, the respective phosphylated nonapeptides could be identified in the digests. After treatment of the pepsin digests with Ba(OH)a in the presence of a nucleophilic tag (a thiol or amine), the phosphylated nonapeptides were transformed into a common tagged nonapeptide that could be analyzed sensitively by means of LC tandem MS. So far, best results were obtained with 2-(3-aminopropylamino)ethanol as nucleophilic tag. By applying the presented method, HuBuChE inhibition can now be monitored accurately by mass spectrometry, without advance knowledge of the structure of the inhibitor. © 2006 American Chemical Society.

In the past years, several text-independent speaker recognition evaluation campaigns have taken place. This paper reports on results of the NIST evaluation of 2004 and the NFI-TNO forensic speaker recognition evaluation held in 2003, and reflects on the history of the evaluation campaigns. The effects of speech duration, training handsets, transmission type, and gender mix show expected behaviour on the DET curves. New results on the influence of language show an interesting dependence of the DET curves on the accent of speakers. We also report on a number of statistical analysis techniques that have recently been introduced in the speaker recognition community, as well as a new application of the analysis of deviance analysis. These techniques are used to determine that the two evaluations held in 2003, by NIST and NFI-TNO, are of statistically different difficulty to the speaker recognition systems.

Achtergrond : De afgelopen jaren is het vraagstuk van maatschappelijke veiligheid door verschillende gebeurtenissen rond radicalisering en terrorisme in een ander daglicht komen te staan. Dit verkennende onderzoek richt zich op een selectie van interventies met als doel radicalisering te voorkomen of tegen te gaan. In dit onderzoek concentreren wij ons op lokale interventies die door eerstelijnswerkers (zoals docenten, politie en jeugdwerkers) uitgevoerd kunnen worden. ---- Doelstelling : Inzicht geven in en structureren van de lokale interventies die er op dit moment voor eerstelijnswerkers in Nederland bestaan om radicalisering te voorkomen en tegen te gaan. ---- Werkwijze : Tijdens dit onderzoek zijn interventies die gericht zijn op het voorkomen en tegengaan van radicalisering verzameld met behulp van een literatuurstudie. Tijdens een clusteranalyse zijn de geïnventariseerde interventies ingedeeld naar werkbare clusters. In twee focusgroepen met experts op het gebied van radicalisering zijn voorwaarden voor de uitvoer van elk van deze clusters verzameld. Ten slotte is in een online vragenlijstonderzoek voor eerstelijnswerkers de perceptie van effectiviteit per cluster van interventies bepaald. ---- Resultaten : Dit onderzoek heeft een vijftiental clusters van preventieve, curatieve en repressieve interventies opgeleverd die zijn gericht op het voorkomen en tegengaan van radicalisering bij rechts en moslims. Naast een beschrijving van de inhoud van deze clusters van interventies zijn voorwaarden voor elk van deze clusters weergegeven die dienen als handvatten voor eerstelijnswerkers bij de uitvoer van hun eigen maatwerk. Ook wordt per cluster van interventies de perceptie van effectiviteit weergegeven. ---- Conclusies : Uit dit onderzoek blijkt dat er meer interventies gericht zijn op het tegengaan van radicalisering bij moslims dan radicalisering bij rechts. Verder blijkt dat er ten opzichte van curatieve en repressieve interventies veel preventieve interventies zijn om radicalisering tegen te gaan. De structuur preventief, curatief, repressief is overigens niet optimaal voor de indeling van de clusters van interventies, omdat veel interventies bij meerdere categorieën ingedeeld kunnen worden. Meer onderscheidend lijkt een indeling naar individueel gerichte versus groepsgerichte interventies. Eerstelijnswerkers zijn over het algemeen vrij positief over de effectiviteit van de clusters van interventies en geven daar een breed scala aan oorzaken voor. Uit de focusgroepen bleek dat de experts minder positief zijn over de effectiviteit van de clusters. Belangrijke algemene voorwaarden voor het slagen van interventies zijn kenmerken en vaardigheden van eerstelijnswerkers, matching tussen eerstelijnswerker en individu of groep, samenwerking van uitvoerders en continuïteit, bereikbaarheid en beschikbaarheid van eerstelijnswerkers. In het ontwikkelen van beleid is het wenselijk dat er rekening gehouden wordt met deze voorwaarden om te komen tot optimale inzet van de beschikbare interventiemethoden.

Simulation-based tactical training can be made more effective by using cognitive software agents to play key roles (e.g. team mate, adversaries, instructor). Due to the dynamic and complex nature of military tactics, it is hard to create agents that behave realistically and support the training leader in keeping control over the scenario. For successful use in training, agents should provide trainees with opportunities to achieve the learning objectives in both simple and complex scenarios. We developed such a cognitive agent, playing the enemy force in a tactical training scenario. The cognitive agent was then integrated in a training simulation and tested with naval officers. Results show that the agent successfully supported achievement of the learning goals.

Ideally, explosion risk is identified and prevented at an early stage of process design, forming a key part of the inherently safer design (ISD) approach. However, in practice, explosion risk often cannot be eliminated completely. Reliable preventive and protective systems must therefore be applied, as part of the now widely applied barrier or independent layer of protection approach (LOPA) to process design. Doing this requires a comprehensive knowledge of available systems. However, such a comprehensive overview of the various systems does not yet exist. This paper provides such an overview. The commercially available explosion prevention and mitigative systems applicable to gas, dust, mist and hybrid (gas-aerosol) explosions are discussed, including basic principles and proper application for single and combined systems, for confined installations. Limitations of the applicability as well as limitations of the research-base of the various systems are also discussed.