Verfahren zur Validierung von Feinstaubausbreitungssimulationen durch Einbringung fluoreszierender Tracerpartikel

Bei der Untersuchung der Ausbreitung von Aerosolen im Außenbereich besteht grundsätzlich die Schwierigkeit, dass es weder möglich ist die Trajektorie einzelner Partikel zu verfolgen, noch einzelne Partikel eindeutig einer Quelle zuzuordnen. Aus diesem Grund ist eine Validierung von Ausbreitungssimulationen nicht ohne Weiteres realisierbar. Deshalb wurde ein Verfahren entwickelt, dass auf einem speziellen Aerosoltracer und einem geeigneten Nachweisverfahren basiert. Bei dem Tracer handelt es sich um BHA Visolite von General Electrics, ein fluoreszierendes Pulver auf Basis von Calciumcarbonat. Zum Nachweis des Tracers war zu Beginn der Arbeit kein automatisiertes Messsystem verfügbar. Aus diesem Grund wurde das "Aerosol Particle Measurement System, kurz APMS, entwickelt. Es handelt sich dabei um ein Messsystem zur Untersuchung von an Oberflächen haftenden Partikeln unter besonderer Berücksichtigung der fluoreszierenden Eigenschaften des Tracers Visolite. Das System besteht aus einer Optik, die mechanisch in drei Dimensionen über eine beliebig geformte Oberfläche geführt werden kann, um die auf der Oberfläche anhaftenden Partikel abzubilden und im Messrechner zu analysieren. Um zwischen dem gesammelten Gesamtstaub und den Tracerpartikeln unterscheiden zu können, wird die Oberfläche abwechselnd mit einer weißen Lichtquelle im Durchlichtverfahren und einer ultravioletten Lichtquelle im Auflichtverfahren beleuchtet und untersucht. Auf diese Weise lassen sich in Feldversuchen die Ergebnisse von Ausbreitungssimulationen mit den experimentellen Daten des APMS vergleichen. Das Validierungsverfahren lässt sich in verschiedene Abschnitte unterteilen. Nach der Dispergierung des Tracers Visolite am Emissionspunkt, werden Konzentrationsmessungen bzw. Depositionsmessungen an verschiedenen Positionen im Ausbreitungsgebiet durchgeführt. Anschließend erfolgt die Auswertung der Messergebnisse sowie deren Vergleich mit den Simulationsergebnissen. Im Rahmen dieser Arbeit wurden insgesamt zwei Messkampagnen an der der Lehr- und Forschungsstation Dikopshof der Universität Bonn durchgeführt. Anhand der Ergebnisse der ersten Messkampagne erfolgte eine Optimierung des gesamten Validierungsverfahrens, einschließlich des APMS, während die Resultate der zweiten Messkampagne zu einererfolgreichen Validierung der Ausbreitungssimulation STAR3D genutzt werden konnten

DYNAMIC DISPERSION MODELLING OF ODOURS AND AEROSOLS

The transmission of dust particles is one of the interesting processes in the dispersion of aerosols. Due to the fact that it is impossible to follow the track of every single particle, a lot of effects and their parameters must be known to simulate the dispersion. At the Harmo 7 conference a dynamic model to simulate the dispersion of odours was presented, before. This model is based on a numerical solution of the Navier-Strokes equation. Building upon this effort the dispersion model was enhanced, so that it is now possible to simulate the dispersion of aerosol particles. Extensive modifications were necessary to consider the aerodynamic and physical characteristics of polydisperse aerosols. Effects as sedimentation, deposition, resuspension and agglomeration of aerosols are or will be integrated into the simulation model. In order to realize a validation of such a complex dispersion model, our research group is developing two independent aerosol tracer systems. Primary attention is paid to the environmental compatibility of the tracer dust. Both procedures are based on fluorescence marked particles, but they differ from each other with regard to their methods of detection. This enables us to practice both procedures at the same time. The dispersion model as well as the validation methods is objects of this paper

The behaviour of political parties and MPs in the parliaments of the Weimar Republic

Copyright @ 2012 The Authors. This is the author's accepted manuscript. The final published article is available from the link below.Analysing the roll-call votes of the MPs of the Weimar Republic we find: (1) that party competition in the Weimar parliaments can be structured along two dimensions: an economic left–right and a pro-/anti-democratic. Remarkably, this is stable throughout the entire lifespan of the Republic and not just in the later years and despite the varying content of votes across the lifespan of the Republic, and (2) that nearly all parties were troubled by intra-party divisions, though, in particular, the national socialists and communists became homogeneous in the final years of the Republic.Zukunftskolleg, University of Konstan

Same Trait, Different Receiver Response: Unlike Females, Male American Goldfinches Do Not Signal Status with Bill Colour

In species in which both sexes have similar ornamentation, the ornaments often function as sexual or social signals in both sexes. However, males and females may use ornaments in different signalling contexts. We previously demonstrated that carotenoid-based bill colour of female American goldfinches, Spinus tristis, functions as a signal of status during intrasexual, but not intersexual, competition. Here we test whether male bill colour functions as a competitive status signal during both intra- and intersexual contests. We tested whether focal males and females avoided feeding adjacent to taxidermic male models as a function of the models’ experimentally altered bill colour. We additionally tested whether male bill colour functions as a mate choice signal by presenting females with a choice of two live males with experimentally altered bill colour. In the status signal experiment, neither focal males nor females avoided male models with more colourful bills, as was predicted by the status-signalling hypothesis. These results indicate that male bill coloration does not function as a signal of competitive status and that the signal function of male bill colour does not parallel that of female bill colour. In our mate choice experiment, females showed no preference for male bill colour, suggesting that male bill colour may have some yet untested signalling function or that male bill colour may no longer be under selection. Our findings suggest that selection can lead to different signalling strategies in males and females, even in species that express mutual ornamentation

Sperm Swimming Velocity Predicts Competitive Fertilization Success in the Green Swordtail Xiphophorus helleri

Sperm competition is expected to favour the evolution of traits that influence the performance of sperm when they compete to fertilize a female's eggs. While there is considerable evidence that selection favours increases in sperm numbers, much less is known about how sperm quality contributes towards competitive fertilization success. Here, we determine whether variation in sperm quality influences competitive fertilization success in the green swordtail Xiphophorus helleri, a highly promiscuous livebearing fish. We use artificial insemination as a method of controlled sperm delivery and show that sperm swimming velocity is the primary determinant of fertilization success when ejaculates from two males compete to fertilize a female's eggs. By contrast, we found no evidence that sperm length had any effect on siring success. We also found no evidence that pre- and postcopulatory sexual traits were phenotypically integrated in this species, suggesting that the previous observation that reproductive skew favours males with high mating rates is unlikely to be due to any direct association between sperm quality and male sexual ornamentation

The effectiveness of mindfulness-based interventions in the perinatal period: a systematic review and meta-analysis

Perinatal mental health difficulties are associated with adverse consequences for parents and infants. However, the potential risks associated with the use of psychotropic medication for pregnant and breastfeeding women and the preferences expressed by women for non-pharmacological interventions mean it is important to ensure that effective psychological interventions are available. It has been argued that mindfulness-based interventions may offer a novel approach to treating perinatal mental health difficulties, but relatively little is known about their effectiveness with perinatal populations. This paper therefore presents a systematic review and meta-analysis of the effectiveness of mindfulness-based interventions for reducing depression, anxiety and stress and improving mindfulness skills in the perinatal period. A systematic review identified seventeen studies of mindfulness-based interventions in the perinatal period, including both controlled trials (n = 9) and pre-post uncontrolled studies (n = 8). Eight of these studies also included qualitative data. Hedge’s g was used to assess uncontrolled and controlled effect sizes in separate meta-analyses, and a narrative synthesis of qualitative data was produced. Pre- to post-analyses showed significant reductions in depression, anxiety and stress and significant increases in mindfulness skills post intervention, each with small to medium effect sizes. Completion of the mindfulness-based interventions was reasonable with around three quarters of participants meeting study-defined criteria for engagement or completion where this was recorded. Qualitative data suggested that participants viewed mindfulness interventions positively. However, between-group analyses failed to find any significant post-intervention benefits for depression, anxiety or stress of mindfulness-based interventions in comparison to control conditions: effect sizes were negligible and it was conspicuous that intervention group participants did not appear to improve significantly more than controls in their mindfulness skills. The interventions offered often deviated from traditional mindfulness-based cognitive therapy or mindfulness-based stress reduction programmes, and there was also a tendency for studies to focus on healthy rather than clinical populations, and on antenatal rather than postnatal populations. It is argued that these and other limitations with the included studies and their interventions may have been partly responsible for the lack of significant between-group effects. The implications of the findings and recommendations for future research are discussed

Detector Structure Development Using Active And Passive Thermography

During the development and production of the mechanical support structures of the PANDA-Micro-Vertex-Detector(MVD)* experiments of passive and active thermography were applied and shown. The combination of mostly carbon-based materials enables the development of lightweight structures, which satisfy the mechanical stability and thermal requirements. The carrier structure of the MVD stripe detector is mainly composed of carbon foams, high fiber content CFC materials and PMI-based foams. This enables to selectively cool areas where heat is generated and to decouple them from the temperature-sensitive areas of the sensor system. Passive thermography is used during our development work mainly to validate the results of thermal simulations, for design optimization and for the functional control of the carrier structure. Additionally active thermography allows us to identify anomalies and thermal disturbances, which remain unnoticed in static processes. Also the investigation and characterization of adhesive layers are possible. For this purpose we developed special software algorithms which are sensitive to small-scale differences in temperature conductivity