Blaming the Refugees? Experimental Evidence On Responsibility Attribution

Do people blame refugees for negative events? We propose a novel experimental paradigm to measure discrimination in responsibility attribution towards Arabic refugees. Participants in the laboratory experience a positive or negative income shock, which is with equal probability caused by a random draw or another participant's performance in a real effort task. Responsibility attribution is measured by beliefs about whether the shock is due to the other participant's performance or the random draw. We find evidence for reverse discrimination: Natives attribute responsibility more favorably to refugees than to other natives. In particular, refugees are less often held responsible for negative income shocks. Moreover, natives with negative implicit associations towards Arabic names attribute responsibility less favorably to refugees than natives with positive associations. Since neither actual performance differences nor beliefs about natives' and refugees' performance can explain our finding of reverse discrimination, we rule out statistical discrimination as the driving force. We discuss explanations based on theories of self-image and identity concerns

Low-Order Reactor Network Based Prediction of Pollutant Emissions Applied to FLOX Combustion

Prediction of pollutant emissions is a key aspect of modern combustor design in energy conversion systems. In the presented work, a simple and robust model based on low-order reaction networks is applied to a FLOX® laboratory combustor at atmospheric conditions. The applied approach is computationally cheap and therefore highly suited for design studies. Steady-state CFD RANS simulations are carried out, serving as a basis for the network generation algorithm. CFD results are validated with experimental data for flow field and combustion. Different degrees of fidelity of reactor network models are taken into consideration and findings are opposed to measurements, evaluating the quality of the low-fidelity models. Validation of CO and NOx emission results of reactor network modeling provides accurate qualitative and quantitative reproduction of experimental findings, depending on the degree of heat loss applied on the combustion system. The introduced approach is therefore readily applicable to large-scale, industrial, and gas turbine combustion

Effiziente, stochastische Vorhersage von turbulentem Brennkammerlärm

Breitbandlärm spielt heutzutage in vielen technischen Anwendungen eine große Rolle. Dessen akkurate numerische Simulation im Bereich der turbulenten Verbrennung ist das Ziel der vorliegenden Arbeit. Lärm kann mithilfe direkter, kompressibler Methoden und Modelle bereits vorhergesagt werden. Allerdings sind solche Verfahren sehr rechenzeitintensiv und nach wie vor wenig validiert. Daher wird hier ein hybrides, stochastisches Verfahren zur Bestimmung turbulenten Verbrennungslärms weiterentwickelt und validiert, um diesen Lärm in komplexen und technisch relevanten Problemstellungen effizient und zuverlässig vorhersagen zu können. Das neue Verfahren FRPM-CN (Fast Random Particle Method for Combustion Noise Prediction) wird zunächst anhand eines generischen Testfalls verifiziert. Die anschließende Modellvalidierung erfolgt mit offenen und eingehausten Strahlflammen. Experimentell ermittelte Druckspektren dienen als Referenz. Im Zuge der Validierungsstudien wird die Erweiterung auf volle räumliche und zeitliche Auflösung sowie die Vorhersagequalität absoluter Schalldruckpegel getestet. Ein im Rahmen dieser Arbeit entwickeltes, semi-analytisches Modell zur Bestimmung der Strahlflammenspektren dient als Kontrollinstanz und Analysetool. 3D FRPM-CN mit der Modellierung physikalischer Schallausbreitung und dreidimensionaler Schall- quellen sagt absolute Schalldruckpegel der Strahlflammenkonfigurationen für unterschiedliche Richtcharakteristiken des turbulenten Lärms voraus. Hierfür ist praktisch keine künstliche Amplitudenskalierung notwendig. Die Validierung der Methode für komplexe Fragestellungen erfolgt durch die Simulation zweier drallstabilisierter Brenner im Labormaßstab unter atmosphärischen Bedingungen. Der Doppeldrallbrenner sowie der PRECCINSTA Brenner werden mithilfe einer Variation unterschiedlicher Modell- und Simulationsparameter untersucht. In beiden Fällen werden absolute Schalldruckpegel mit 3D FRPM-CN allein auf Grundlage integraler Turbulenzstatistiken und einer Verteilung der Temperaturvarianz in einem definierten Quellgebiet genau wiedergegeben

Kettenfahrzeug mit automatischem Lichtnachführungssystem

Im Rahmen des Projektseminars Elektrotechnik/Informationstechnik soll ein Fahrzeug mit automatischer, sensorgesteuerter, zweiachsiger Nachführung konstruiert werden, dass sich damit selbständig in Richtung der Sonne ausrichten kann. Dies ermöglicht einer Photovoltaikanlage, beispielsweise auf einem Rover, eine möglichst effiziente Stromerzeugung. In dieser Arbeit wird die Idee zur Umsetzung eines solchen Systems sowie die Realisierung mit Hilfe eines über MATLAB angesteuerten LEGO-Mindstorms-Sets beschrieben. Dabei ein Kettenfahrzeug entstanden, das sich sowohl auf der Stelle in die hellste Richtung ausrichten als auch den hellsten Ort auf einer Ebene selbständig ausfindig machen kann

Flow cytometry analysis of the effect of allopurinol and the dinitroaniline compound (Chloralin) on the viability and proliferation of Leishmania infantum promastigotes

BACKGROUND: Leishmaniasis is a major parasitic disease in the tropical regions. However, Leishmania infantum has recently emerged as a very important cause of opportunistic infections for individuals positive for human immunodeficiency virus (HIV). However, there is a lack of in vitro tests for assessing the effect of anti-parasitic drugs on the viability and proliferation of Leishmania infantum. The aim of this study is to assess the efficacy of anti-parasitic drugs like allopurinol and Chloralin on the viability and proliferation of L. infantum promastigotes by utilizing two complementary flow cytometric approaches after exposure of the promastigotes to various concentrations of the drugs. RESULTS: The density of the cultures in the presence and absence of allopurinol was determined by haemocytometer enumeration. The two flow cytometric approaches used to monitor the drug effect were: (i) a quantitative method to measure cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining and (ii) evaluation of cell viability by dual-staining with the membrane-permeable nuclear stain, SBRY-14 and propidium iodide. It was found that concentrations of allopurinol above 50 μg/ml yielded a clear decrease in the proliferation rate of the promastigotes. However, the viability results showed that about 46.8% of the promastigotes incubated in the presence of 800 μg/ml of allopurinol were still alive after 96 hours. In sharp contrast, more than 90% of promastigotes treated with Chloralin 10 μM (2.7 μg/ml) were dead after 48 hours of treatment. These flow cytometric findings suggest that allopurinol has a leishmaniostatic effect while the dinitroaniline compound (Chloralin) has a leishmaniocidal effect against promastigotes. CONCLUSIONS: The flow cytometric data on proliferation and viability were consistent with results obtained from haemocytometer counts and allowed us to develop a model for assessing in vitro the effects of medicaments like allopurinol and chloralin on L. infantum promastigotes on a cellular level

Sweet cherry flesh cells burst in non-random clusters along minor veins

Main conclusion: Sweet cherry flesh cells burst when exposed to water but they do so in clusters indicating heterogeneity with respect to osmotic concentration, which depends on proximity to a minor vein. Abstract: Water plays a key role in cracking in sweet cherry fruit. Magnetic resonance imaging has previously indicated preferential partitioning of water along veins. A more negative osmotic potential along veins seems the likely explanation. Here we establish if cell bursting in mature sweet cherry fruit is also associated with the veins. Cell bursting was identified by a novel light microscope technique involving exposure of a cut fruit surface to water or to sucrose solutions. Upon exposure to water there was no bursting of skin cells but for cells of the flesh (mesocarp) bursting increased with time. When the cut surface was exposed to sucrose solutions of decreasing osmotic concentrations (increasing water potentials) the incidence of cell bursting increased from hypertonic (no bursting), to isotonic, to hypotonic. Cell bursting in the outer mesocarp occurred primarily in the vicinity of minor veins that in the inner mesocarp was primarily between radial veins. The median distance between a minor vein and a bursting cell (mean diameter 0.129 mm) was about 0.318 mm that between a radial vein and a bursting cell was about 0.497 mm. In contrast, the distance between adjacent minor veins averaged 2.57 mm, that between adjacent radial veins averaged 0.83 mm. Cell bursting tends to occur in clusters. Mapping of cell bursting indicates (1) that a seemingly uniform population of mesocarp cells actually represents a heterogeneous population with regard to their cell osmotic potentials and (2) cell bursting afflicts clusters of neighbouring cells in the vicinities of minor veins

Accurate Quantification of Anthocyanin in Red Flesh Apples Using Digital Photography and Image Analysis

Red fleshed apples (Malus × domestica Borkh.) differ in colour intensity between cultivars, seasons and sites. The objective of this study was to develop a procedure for predicting anthocyanin content from digital images of flesh discs. Flesh cylinders of uniform colour were excised, scanned and their colours determined in the R, G and B and the L*a*b* colour spaces. Anthocyanin content was also quantified chemically. A calibration line was constructed to predict anthocyanin content of flesh discs of varying colour from a scan or a photograph in the studio or outdoors. Anthocyanin concentration was linearly related to the logarithms of G, B and L*. From these relationships, the anthocyanin content of a flesh disc was predicted, pixel by pixel. Colour corrections were applied using a reference colour chart included in all images. The Finlayson algorithm was most effective for correcting the G parameter obtained by a flatbed scanner. For variable imaging methods (scanning or photography), the Vandermonde algorithm for correcting the L* parameter and the Finlayson algorithm for correcting the G parameter were most effective in predicting anthocyanin content. The procedure allows accurate prediction of anthocyanin content of red fleshed apples from simple colour scans or photographs