Estimating the effects of Cry1F Bt-maize pollen on non-target Lepidoptera using a mathematical model of exposure

In farmland biodiversity, a potential risk to the larvae of non-target Lepidoptera from genetically modified (GM) Bt-maize expressing insecticidal Cry1 proteins is the ingestion of harmful amounts of pollen deposited on their host plants. A previous mathematical model of exposure quantified this risk for Cry1Ab protein. We extend this model to quantify the risk for sensitive species exposed to pollen containing Cry1F protein from maize event 1507 and to provide recommendations for management to mitigate this risk.A 14-parameter mathematical model integrating small- and large-scale exposure was used to estimate the larval mortality of hypothetical species with a range of sensitivities, and under a range of simulated mitigation measures consisting of non-Bt maize strips of different widths placed around the field edge.The greatest source of variability in estimated mortality was species sensitivity. Before allowance for effects of large-scale exposure, with moderate within-crop host-plant density and with no mitigation, estimated mortality locally was <10% for species of average sensitivity. For the worst-case extreme sensitivity considered, estimated mortality locally was 99·6% with no mitigation, although this estimate was reduced to below 40% with mitigation of 24-m-wide strips of non-Bt maize. For highly sensitive species, a 12-m-wide strip reduced estimated local mortality under 1·5%, when within-crop host-plant density was zero. Allowance for large-scale exposure effects would reduce these estimates of local mortality by a highly variable amount, but typically of the order of 50-fold.Mitigation efficacy depended critically on assumed within-crop host-plant density; if this could be assumed negligible, then the estimated effect of mitigation would reduce local mortality below 1% even for very highly sensitive species.Synthesis and applications. Mitigation measures of risks of Bt-maize to sensitive larvae of non-target lepidopteran species can be effective, but depend on host-plant densities which are in turn affected by weed-management regimes. We discuss the relevance for management of maize events where cry1F is combined (stacked) with a herbicide-tolerance trait. This exemplifies how interactions between biota may occur when different traits are stacked irrespective of interactions between the proteins themselves and highlights the importance of accounting for crop management in the assessment of the ecological impact of GM plants

Die Organisation territorialer Herrschaft und makroökonomische Performanz in den OECD-Ländern

In der politikwissenschaftlichen Föderalismusforschung spielt die Frage nach der Bedeutung und den Auswirkungen von territorialer Herrschaftsorganisation eine zentrale Rolle. Diese Fragestellung kann weiter in die Analyse der Auswirkungen von territorialer Herrschaft für die Demokratiequalität sowie den Effekten hinsichtlich der makroökonomischen Performanz von politischen Systemen unterteilt werden. In dieser Arbeit steht der letztgenannte Aspekt im Vordergrund: Ich stelle die Behauptung auf, dass für die Untersuchung der Auswirkungen von territorialer Herrschaftsorganisation zwischen den Entscheidungskompetenzen (Föderalismus) und den Implementierungskompetenzen (Dezentralisierung) unterschieden werden muss. Ich entwickele daher eine theoretische Argumentation, mit der die Effekte von unterschiedlichen Kompetenzverteilungen auf der zentralen und der subnationalen Ebene erfasst werden. Die einzelnen theoretischen Argumente werden dann anhand einer quantitativen Analyse für die OECD-Staaten getestet. Dabei ergibt sich eine eindeutige Bestätigung für die vorgeschlagene Abgrenzung von Entscheidungs- und Implementierungskompetenzen. Darüber hinaus macht die Arbeit deutlich, dass neben der Analyse von makroökonomischen Performanzeffekten die Untersuchung einzelner Politikfelder verstärkt in den Blickpunkt der Forschung rücken sollte. Abschließend gebe ich daher einen Ausblick, wie aufbauend auf den Befunden dieser Arbeit weitere Erkenntnisse zu den Auswirkungen territorialer Herrschaft gewonnen werden können

Biological Characterization of Novel Inhibitors of the Gram-Positive DNA Polymerase IIIC Enzyme

Novel N-3-alkylated 6-anilinouracils have been identified as potent and selective inhibitors of bacterial DNA polymerase IIIC, the enzyme essential for the replication of chromosomal DNA in gram-positive bacteria. A nonradioactive assay measuring the enzymatic activity of the DNA polymerase IIIC in gram-positive bacteria has been assembled. The 6-anilinouracils described inhibited the polymerase IIIC enzyme at concentrations in the nanomolar range in this assay and displayed good in vitro activity (according to their MICs) against staphylococci, streptococci, and enterococci. The MICs of the most potent derivatives were about 4 μg/ml for this panel of bacteria. The 50% effective dose of the best compound (6-[(3-ethyl-4-methylphenyl)amino]-3-{[1-(isoxazol-5-ylcarbonyl)piperidin-4-yl]methyl}uracil) was 10 mg/kg of body weight after intravenous application in a staphylococcal sepsis model in mice, from which in vivo pharmacokinetic data were also acquired