2,066 research outputs found
Kooperation und die Aufteilung des Kooperationsgewinns bei horizontaler Politikverflechtung
Zur Reform des Verbändestaates
Verbände organisieren Interessen, und zwar partikulare Interessen. Zuerst denken wir hierbei selbstverständlich an Interessen, die bereits ihrem Inhalt nach nur eine bestimmte Personengruppe berühren und mit anderen Interessen im Konflikt liegen oder zumindest mit ihnen konkurrieren - etwa an Einkommensinteressen, wie sie vor allem von Verbänden im Bereich der Wirtschaft vertreten werden. --
Towards a quantum-chemical description of crystalline insulators: A Wannier-function-based Hartree-Fock study of Li2O and Na2O
A recently proposed approach for performing electronic-structure calculations
on crystalline insulators in terms of localized orthogonal orbitals is applied
to the oxides of lithium and sodium, Li2O and Na2O. Cohesive energies, lattice
constants and bulk moduli of the aforementioned systems are determined at the
Hartree-Fock level, and the corresponding values are shown to be in excellent
agreement with the values obtained by a traditional Bloch-orbital-based
Hartree-Fock approach. The present Wannier-function-based approach is expected
to be advantageous in the treatment of electron-correlation effects in an
infinite solid by conventional quantum-chemical methods.Comment: 15 Pages, RevTex, 3 postscript figures (included), to appear in the
Journal of Chemical Physics, May 15, 199
Characterisation of the ERF102 to ERF105 genes of Arabidopsis thaliana and their role in the response to cold stress
The ETHYLENE RESPONSE FACTOR (ERF) genes of Arabidopsis thaliana form a large family encoding plant-specific transcription factors. Here, we characterise the four phylogenetically closely related ERF102/ERF5, ERF103/ERF6, ERF104 and ERF105 genes. Expression analyses revealed that these four genes are similarly regulated by different hormones and abiotic stresses. Analyses of tissue-specific expression using promoter:GUS reporter lines revealed their predominant expression in root tissues including the root meristem (ERF103), the quiescent center (ERF104) and the root vasculature (all). All GFP-ERF fusion proteins were nuclear-localised. The analysis of insertional mutants, amiRNA lines and 35S:ERF overexpressing transgenic lines indicated that ERF102 to ERF105 have only a limited impact on regulating shoot and root growth. Previous work had shown a role for ERF105 in the cold stress response. Here, measurement of electrolyte leakage to determine leaf freezing tolerance and expression analyses of cold-responsive genes revealed that the combined activity of ERF102 and ERF103 is also required for a full cold acclimation response likely involving the CBF regulon. These results suggest a common function of these ERF genes in the response to cold stress
Ab initio simulations of liquid NaSn alloys: Zintl anions and network formation
Using the Car-Parrinello technique, ab initio molecular dynamics simulations
are performed for liquid NaSn alloys in five different compositions (20, 40,
50, 57 and 80 % sodium). The obtained structure factors agree well with the
data from neutron scattering experiments. The measured prepeak in the structure
factor is reproduced qualitatively for most compositions. The calculated and
measured positions of all peaks show the same trend as function of the
composition.\\ The dynamic simulations also yield information about the
formation and stability of Sn clusters (Zintl anions) in the liquid. In our
simulations of compositions with 50 and 57 % sodium we observe the formation of
networks of tin atoms. Thus, isolated tin clusters are not stable in such
liquids. For the composition with 20 % tin only isolated atoms or dimers of tin
appear, ``octet compounds'' of one Sn atom surrounded by 4 Na atoms are not
observed.Comment: 12 pages, Latex, 3 Figures on reques
- …
