Extensions of tempered representations

Let $\pi, \pi'$ be irreducible tempered representations of an affine Hecke algebra H with positive parameters. We compute the higher extension groups $Ext_H^n (\pi,\pi')$ explicitly in terms of the representations of analytic R-groups corresponding to $\pi$ and $\pi'$. The result has immediate applications to the computation of the Euler-Poincar\'e pairing $EP(\pi,\pi')$, the alternating sum of the dimensions of the Ext-groups. The resulting formula for $EP(\pi,\pi')$ is equal to Arthur's formula for the elliptic pairing of tempered characters in the setting of reductive p-adic groups. Our proof applies equally well to affine Hecke algebras and to reductive groups over non-archimedean local fields of arbitrary characteristic. This sheds new light on the formula of Arthur and gives a new proof of Kazhdan's orthogonality conjecture for the Euler-Poincar\'e pairing of admissible characters.Comment: This paper grew out of "A formula of Arthur and affine Hecke algebras" (arXiv:1011.0679). In the second version some minor points were improve

Metaproteome analysis reveals that syntrophy, competition, and phage-host interaction shape microbial communities in biogas plants

Background: In biogas plants, complex microbial communities produce methane and carbon dioxide by anaerobic digestion of biomass. For the characterization of the microbial functional networks, samples of 11 reactors were analyzed using a high-resolution metaproteomics pipeline. Results: Examined methanogenesis archaeal communities were either mixotrophic or strictly hydrogenotrophic in syntrophy with bacterial acetate oxidizers. Mapping of identified metaproteins with process steps described by the Anaerobic Digestion Model 1 confirmed its main assumptions and also proposed some extensions such as syntrophic acetate oxidation or fermentation of alcohols. Results indicate that the microbial communities were shaped by syntrophy as well as competition and phage-host interactions causing cell lysis. For the families Bacillaceae, Enterobacteriaceae, and Clostridiaceae, the number of phages exceeded up to 20-fold the number of host cells. Conclusion: Phage-induced cell lysis might slow down the conversion of substrates to biogas, though, it could support the growth of auxotrophic microbes by cycling of nutrients. © 2019 The Author(s)

EU Agro Biogas Project

EU-AGRO-BIOGAS is a European Biogas initiative to improve the yield of agricultural biogas plants in Europe, to optimise biogas technology and processes and to improve the efficiency in all parts of the production chain from feedstock to biogas utilisation. Leading European research institutions and universities are cooperating with key industry partners in order to work towards a sustainable Europe. Fourteen partners from eight European countries are involved. EU-AGRO-BIOGAS aims at the development and optimisation of the entire value chain – to range from the production of raw materials, the production and refining of biogas to the utilisation of heat and electricity

Palladiumkatalysierte Dominoarylierung substituierter und anellierter Cyclopentadiene - eine neue Synthesemethode fuer Pentaarylcyclopentadiene

Cyclopentadiene and metallocenes, typically zirconocene dichloride, are suitable substrates for multiple arylations with aryl bromides in palladium-catalyzed reactions. Thus various aryl bromides bearing either an electron-donating or an electron-withdrawing substituent can react with these substrates to afford the corresponding 1,2,3,4,5-pentaarylcyclopenta-1,3-dienes in a single preparative step. Derivatives of cyclopentadiene, including di- and tri- substituted cyclopentadienes, and azulene are arylated in a similar fashion. Transformations at the functional groups of the pentaarylcyclopentadienes result in pentapodal dendrimer-like systems and sterically demanding stilbenes. The synthesis of conjugated organic oligomers containing pentaarylcyclopentadien units with molecular weights up to 4500 g/mol and electrical conductivities from about 9.6 10E-8 S/cm were achieved by intermolecular McMurry-coupling. (orig.)SIGLEAvailable from: http://www.ub.uni-duisburg.de/diss/diss0104 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Adaptive Computation of the Current-Carrying Plasma in an MPD Rocket Thruster

This paper will present numerical methods and results for the adaptive computation of a hot-anode MPD thruster currently being operated at the Institut fur Raumfahrtsysteme