Witterungsextreme und ihre Bedeutung für die jährlichen Ertragsabweichungen von Winterweize

KlimafolgenFür die Landwirtschaft stellen Witterungsereignisse mit signifikanten Abweichungen von langjährigen Mittel eine große Herausforderung dar. Witterungsextreme wie Starkregen, Hitzeperioden während kritischer phänologischer Phasen wie beispielsweise der Blüte oder längere niederschlagsfreie Zeiten haben oftmals direkte Auswirkungen auf den Ertrag und die Qualität der Ernteprodukte. Durch den Klimawandel werden zudem die Wiederkehr von Extremereignissen und die Intensität von Witterungsereignissen beeinflusst. Die Bedeutung der Witterungsextreme für die jährlichen Ertragsschwankungen von Winterweizen wurde durch die Auswertung der Langzeitversuche des JKI in Dahnsdorf, Brandenburg untersucht. Die Klimadaten entstammen der Wetterstation auf dem Versuchsfeld und fehlende Daten sind durch Interpolation von umliegenden Klimastationen auf diesen Standort für die Zeit von 1993-2013 erzeugt worden. Während des Untersuchungszeitraums betrug die jährliche Durchschnittstemperatur 9.6°C und der Jahresniederschlag lag bei 587 mm. Die Anzahl aufeinanderfolgender Tage ohne Niederschlag (NCDWP) von April-September und die Temperatur >25°C (NHD) zur Blüte von Winterweizen im Zeitraum vom 1.-21.Juni in Kombination mit unterschiedlichen Pflanzenschutzstrategien wurde hinsichtlich der Bedeutung für die jährlichen Ertragsschwankungen analysiert. Sowohl bei den NCDWP als auch bei den NHD konnte für den Betrachtungszeitraum für die Werte oberhalb des 80%-igen Perzentils eine leichte Zunahme beider Extrema für diesen Standort gefunden werden (Zunahme von 5 auf 6 bei NHD und 14 auf 15 bei NCDWP). Eine Regressionsanalyse für den Zeitraum von 1996-2007 ergab für beide Extrema ertragsrelevante Auswirkungen auf die jährlichen Ertragsschwankungen. Hierbei zeigten die NHD eine deutlich stärkere ertragsrelevante Auswirkung als die NCDWP bei Winterweizen, abhängig von den jeweiligen Pflanzenschutzstrategien

Confirmation of the cardiac safety of nolasiban in a randomised cohort of healthy female volunteers.

Nolasiban is an orally active oxytocin receptor antagonist being developed to increase the efficiency of assisted reproductive technologies. This study evaluated the pharmacokinetics, pharmacodynamics, and cardiac safety of nolasiban in 45 healthy women of child-bearing age. Nolasiban was administered in a fasted state with a standardised lunch served 4.5 h post-dose. Concentration-effect modelling was used to assess the effect of two dosages of nolasiban (900 mg and 1800 mg) on QTc following single-dose administration. We found no significant change in QTc at all tested dosages. Two-sided 90% confidence intervals of geometric mean Cmax for estimated QTc effects of nolasiban were below the threshold of regulatory concern. The sensitivity of the assay to detect small changes in QTc was confirmed by a significant shortening of QTc between 2 and 4 h after consumption of a meal, which served to validate the model. Independent of the nolasiban assessment, this study also explored the effects of sex hormones on ECG parameters, especially QT subintervals. We found a significant relationship between JTpc and oestradiol. Heart rate was negatively correlated with progesterone. This study confirms the cardiovascular safety of nolasiban and describes relationships of sex hormones and ECG parameters

Concentration-QT modelling of the novel DHFR inhibitor P218 in healthy male volunteers.

AIMS: Given the increasing emergence of drug resistance in Plasmodium, new antimalarials are urgently required. P218 is an aminopyridine that inhibits dihydrofolate reductase being developed as a malaria chemoprotective drug. Assessing the effect of new compounds on cardiac intervals is key during early drug development to determine their cardiac safety. METHODS: This double-blind, randomized, placebo-controlled, parallel group study evaluated the effect of P218 on electrocardiographic parameters following oral administration of seven single-ascending doses up to 1000 mg in 56 healthy volunteers. Participants were randomized to treatment or placebo at a 3:1 ratio. P218 was administered in the fasted state with standardized lunch served 4 hours after dosing. 12-lead ECGs were recorded in triplicate at regular intervals on the test day, and at 48, 72, 120, 168, 192 and 240 hours thereafter. Blood samples for pharmacokinetic evaluations were collected at similar time points. Concentration-effect modelling was used to assess the effect of P218 and its metabolites on cardiac intervals. RESULTS: Concentration-effect analysis showed that P218 does not prolong the QTcF, J-Tpeak or TpTe interval at all doses tested. No significant changes in QRS or PR intervals were observed. Two-sided 90% confidence intervals of subinterval effects of P218 and its metabolites were consistently below the regulatory concern threshold for all doses. Study sensitivity was confirmed by significant shortening of QTcF after a meal. CONCLUSION: Oral administration of P218 up to 1000 mg does not prolong QTcF and does not significantly change QRS or PR intervals, suggesting low risk for drug-induced proarrhythmia

Do Parties Matter? Estimating the Effect of Political Power in Multi-Party Systems

This paper estimates the effect of political power on tax policies in municipal councils under a proportional election system. The main challenge in estimating the causal effect of parties on policy is to isolate the effect of power from underlying voter preferences and the selection effect of parties. We use an instrumental variable approach where close elections provide the exogenous variation in our variable of interest: voting power. Using data from German municipalities in the state of Bavaria, our estimation results suggest that power does matter. Somewhat surprisingly, the center-left party SPD is found to lower all three locally controlled taxes, whereas The Greens increase both property taxes considerably. These results remain robust across a range of specifications. What is more, the effect of the SPD is confirmed by a simple regression discontinuity estimation of mayors in these local governments

Overlapping political budget cycle

We advance the literature on political budget cycles by testing for cycles in expenditures for elections to the legislative and the executive branches. Using municipal data, we identify cycles independently for the two branches, evaluate the effects of overlaps, and account for general year effects. We find sizable effects on expenditures before legislative elections and even larger effects before joint elections to the legislature and the office of mayor. In the case of coincident elections, we show that it is important whether the incumbent chief executive seeks reelection. To account for the potential endogeneity of that decision, we apply an IV approach using age and pension eligibility rules

Antarctic pack ice algal distribution: Floe-scale spatial variability and predictability from physical parameters

©2017. Commonwealth of Australia. Antarctic pack ice serves as habitat for microalgae which contribute to Southern Ocean primary production and serve as important food source for pelagic herbivores. Ice algal biomass is highly patchy and remains severely undersampled by classical methods such as spatially restricted ice coring surveys. Here we provide an unprecedented view of ice algal biomass distribution, mapped (as chlorophyll a) in a 100 m by 100 m area of a Weddell Sea pack ice floe, using under-ice irradiance measurements taken with an instrumented remotely operated vehicle. We identified significant correlations (p < 0.001) between algal biomass and concomitant in situ surface measurements of snow depth, ice thickness, and estimated sea ice freeboard levels using a statistical model. The model's explanatory power (r2 = 0.30) indicates that these parameters alone may provide a first basis for spatial prediction of ice algal biomass, but parameterization of additional determinants is needed to inform more robust upscaling efforts

The inhibitory effect of an RGD-human chitin-binding domain fusion protein on the adhesion of fibroblasts to reacetylated chitosan films

Biomaterials used for tissue engineering applications must provide a structural support for the tissue development and also actively interact with cells, promoting adhesion, proliferation, and differentiation. To achieve this goal, adhesion molecules may be used, such as the tripeptide Arg-Gly-Asp (RGD). A method based on the use of a carbohydrate-binding module, with affinity for chitin, was tested as an alternative approach to the chemical grafting of bioactive peptides. This approach would simultaneously allow the production of recombinant peptides (alternatively to peptide synthesis) and provide a simple way for the specific and strong adsorption of the peptides to the biomaterial. A fusion recombinant protein, containing the RGD sequence fused to a human chitin-binding module (ChBM), was expressed in E. coli. The adhesion of fibroblasts to reacetylated chitosan (RC) films was the model system selected to analyze the properties of the obtained proteins. Thus, the evaluation of cell attachment and proliferation on polystyrene surfaces and reacetylated chitosan films, coated with the recombinant proteins, was performed using mouse embryo fibroblasts 3T3. The results show that the recombinant proteins affect negatively fibroblasts anchorage to the materials surface, inhibiting its adhesion and proliferation. We also conclude that this negative effect is fundamentally due to the human chitin-binding domain.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/27359/2006, POCTI/BIO/45356/200

Does It Pay To Be a Woman? Labour Demand Effects of Maternity-Related Job Protection and Replacement Incomes

In countries with strong employment protection laws it is often considered to be unwise to hire a woman in childbearing age because she might get pregnant. However, such labour demand e ects of job protection measures related to maternity leave are often rather anecdotal. To provide analytical evidence, this paper studies the impact of changes in maternity-related job protection in Germany on employment opportunities for women in childbearing age without children for whom the observed e ects should be largely demand-related. Exogenous, discrete policy changes in the German labour market of the 1980s and 1990s constitute the setting for a difference-in-differences analysis of the transition into employment as well as wages. The data for this study are taken from the German Socio-Economic Panel and from the German Microcensus. Doubling the job-protected leave period from 6 months to 12 months between 1986 and 1988 led to an approximately 6% lower probability of being hired for women in childbearing age without a university degree.In addition, I nd a 5-10% increase in wages for women in childbearing age associated with the latter reform. Since this effect disappears when controlling for having a child in the future, this may indicate an increased need to signal commitment by increased effort after the reform