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In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination.
A piezoelectric biosensor has been developed on the basis of the reversible acetylcholinesterase (AChE) inhibitor propidium. The propidium cation was bound to a 11-mercaptoundecanoic acid monolayer on gold-coated quartz crystals. The immobilization was done via activation of carboxyl groups by 1,3-dicyclohexylcarbodiimide (DCC). Different types of cholinesterases (acetyl- and butyryl-ChE) from different origins were tested for their binding ability towards the immobilized propidium. Binding Studies were performed in a flow system, Furthermore, catalytically active and organophosphate-inhibited enzyme were compared re-aiding their binding capability. The binding constants were derived by using an one to one binding model and a refined model also including rebinding effects. It was shown that organophosphorylation of the active site hardly influences the affinity of AChE towards propidium. Furthermore the propidium-based biosensor provides equal sensitivity as compared with piezolelectric sensors with immobilized paraoxon- an active site ligand of AChE. (c) 2005 Elsevier B.V. All rights reserved
The inhomogeneous partial derivative-equation is an inexhaustible source of locally unsolvable equations, subelliptic estimates and other phenomena in partial differential equations. Loosely speaking, for the analysis on complex manifolds with boundary nonelliptic problems are typical rather than elliptic ones. Using explicit integral representations we assign a Fredholm complex to the Dolbeault complex over an arbitrary bounded domain in C-n. (C) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
The potassium channel AKT2 plays important roles in phloem loading and unloading. It can operate as inward-rectifying channel that allows H+-ATPase-energized K+ uptake. Moreover, through reversible post-translational modifications it can also function as an open, K+-selective channel, which taps a ‘potassium battery’, providing additional energy for transmembrane transport processes. Knowledge about proteins involved in the regulation of the operational mode of AKT2 is very limited. Here, we employed a large-scale yeast two-hybrid screen in combination with fluorescence tagging and null-allele mutant phenotype analysis and identified the plasma membrane localized receptor-like kinase MRH1/MDIS2 (AT4G18640) as interaction partner of AKT2. The phenotype of the mrh1-1 knockout plant mirrors that of akt2 knockout plants in energy limiting conditions. Electrophysiological analyses showed that MRH1/MDIS2 failed to exert any functional regulation on AKT2. Using structural protein modeling approaches, we instead gathered evidence that the putative kinase domain of MRH1/MDIS2 lacks essential sites that are indispensable for a functional kinase suggesting that MRH1/MDIS2 is a pseudokinase. We propose that MRH1/MDIS2 and AKT2 are likely parts of a bigger protein complex. MRH1 might help to recruit other, so far unknown partners, which post-translationally regulate AKT2. Additionally, MRH1 might be involved in the recognition of chemical signals.
In 2013, large floods affected Germany heavily. The natural disaster transcended jurisdictional and organisational boundaries, necessitating a coordinative effort by disaster relief forces and their administrative and political leadership. In the aftermath, politicians and experts praised the improvement of the German system of crisis management, also in direct comparison with the response to the last German “flood of the century” of 2002. This chapter takes a public policy and organisational perspective to analyse the German disaster relief governance throughout all four crisis management phases. By highlighting the central features of the German governance arrangements and the main organisational changes implemented in reaction to the previous flood in 2002, we find that Whole-of-Government approaches are increasingly used by the federal and Länder government.
Seismic wide-angle data were collected along a 40-km-long profile centered at the geothermal research well GrSk 3/90 in the Northeast German Basin. Tomographic inversion of travel time data provided a velocity and a vertical velocity gradient model, indicative of Cenozoic to Pre-Permian sediments. Wide-angle reflections are modeled and interpreted as top Zechstein and top Pre-Permian. Changes in velocity gradients are interpreted as the transition from mechanical to chemical compaction at 2-3 km depth, and localized salt structures are imaged, suggesting a previously unknown salt pillow in the southern part of the seismic profile. The Zechstein salt shows decreased velocities in the adjacent salt pillows compared to the salt lows, which is confirmed by sonic log data. This decrease in velocity could be explained by the mobilization of less dense salt, which moved and formed the salt pillows, whereas the denser salt remained in place at the salt lows. We interpret a narrow subvertical low-velocity zone under the salt pillow at GrSk 3/ 90 as a fault in the deep Permian to Pre-Permian. This WNW-ESE trending fault influenced the location of the salt tectonics and led to the formation of a fault-bounded graben in the Rotliegend sandstones with optimal mechanical conditions for geothermal production. Thermal modeling showed that salt pillows are related to chimney effects, a decrease in temperature, and increasing velocity. The assumed variations in salt lithology, density, and strain must thus be even higher to compensate for the temperature effect.
We prove the existence of a limit in Hm(D) of iterations of a double layer potential constructed from the Hodge parametrix on a smooth compact manifold with boundary, X, and a crack S ⊂ ∂D, D being a domain in X. Using this result we obtain formulas for Sobolev solutions to the Cauchy problem in D with data on S, for an elliptic operator A of order m ≥ 1, whenever these solutions exist. This representation involves the sum of a series whose terms are iterations of the double layer potential. A similar regularisation is constructed also for a mixed problem in D.
An der Universität Potsdam wurden im Rahmen des Qualitätspakt Lehre-Projekts „Qualität etablieren in Lehre und Lernen (QueLL)“ Maßnahmen für eine Verbesserung der Studienbedingungen und eine Weiterentwicklung der Lehre und des Lernens durchgeführt. Die während der neunjährigen Projektlaufzeit thematisierten Fragestellungen, erarbeiteten Lösungsansätze und entsprechenden Erfahrungen werden im vorliegenden Sammelband in Form von wissenschaftlichen Auseinandersetzungen und Werkstattberichten dargestellt und diskutiert.
Die Beiträge spiegeln in ihrer thematischen Vielfalt unterschiedliche universitäre Übergangsphasen wider, wie in diesem Fall den Übergang in die Hochschule, Übergänge innerhalb der Hochschule (im Kontext der Organisationsentwicklung, der Weiterbildung akademischer Statusgruppen oder der Entwicklung einer digitalen Lehr-Lernkultur) und schließlich den Übergang in die Berufspraxis. Denn während der Projektlaufzeit hat sich gezeigt, dass die Gestaltung von Lehre und Lernen letztlich immer eine Gestaltung solcher Übergänge ist: sowohl zwischen den innerinstitutionellen Ebenen und Bereichen als auch zwischen Akteur/innen der Hochschule und schließlich ebenso innerhalb des Student Life Cycle. Weiterhin wird anhand der Beiträge deutlich, dass die Entwicklung von Lehre und Studium nicht als isolierte Aufgabe verstanden werden kann, sondern in die Strukturen und Prozesse der Universität hineinwirken und Formen der Zusammenarbeit etablieren sollte, die es braucht, um Projekte nachhaltig zu gestalten.
Ziel dieses Bandes ist es, zur Diskussion über Gelingensbedingungen einer nachhaltigen Entwicklung von Lehre und Lernen beizutragen. Damit richtet er sich an Akteur/innen aus der Hochschulleitung, an Lehrende und Forschende sowie Mitarbeitende des Third Space.