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On quantum corrections to spinning strings and Bethe equations
(2005)Physics Letters BRecently, it was demonstrated that one-loop energy shifts of spinning superstrings on AdS5 x S5 agree with certain Bethe equations for quantum strings at small effective coupling. However, the string result required artificial regularization by zeta-function. Here we show that this matching is indeed correct up to fourth order in effective coupling; beyond, we find new contributions at odd powers. We show that these are reproduced by ...Journal Article -
Fluctuations and energy shifts in the Bethe ansatz
(2005)Physics Letters BWe study fluctuations and finite size corrections for the ferromagnetic thermodynamic limit in the Bethe ansatz for the Heisenberg WWW 1/2 spin chain, which is the AdS/CFT dual of semiclassical spinning strings. For this system we derive the standard quantum mechanical formula which expresses the energy shift as a sum over fluctuation energies. As an example we apply our results to the simplest, one-cut solution of this system and derive ...Journal Article -
Sicherheit und Verunsicherung im Zeitalter elektronischer Wissenschaftskommunikation
(2005)B.I.T. onlineJournal Article -
Formation of ice supersaturation by mesoscale gravity waves
(2005)Atmospheric Chemistry and PhysicsWe investigate the formation and evolution of an ice-supersaturated region (ISSR) that was detected by means of an operational radiosonde sounding launched from the meteorological station of Lindenberg on 21 March 2000, 00:00 UTC. The supersaturated layer was situated below the local tropopause, between 320 and 408 hPa altitude. Our investigation uses satellite imagery from METEOSAT and the Advanced Very High Resolution Radiometer (AVHRR) ...Journal Article -
Exploitative and Hierarchical Antagonism in a Cooperative Bacterium
(2005)PLoS BiologySocial organisms that cooperate with some members of their own species, such as close relatives, may fail to cooperate with other genotypes of the same species. Such noncooperation may take the form of outright antagonism or social exploitation. Myxococcus xanthus is a highly social prokaryote that cooperatively develops into spore-bearing, multicellular fruiting bodies in response to starvation. Here we have characterized the nature of ...Journal Article -
On the extremality of Hofer's metric on the group of Hamiltonian diffeomorphisms
(2005)International Mathematics Research NoticesLet M be a closed symplectic manifold, and let k · k be a norm on the space of all smooth functions on M, which are zero-mean normalized with respect to the canonical volume form. We show that if k· k ≤ Ck · k∞, and k · k is invariant under the action of Hamiltonian diffeomorphisms, then it is also invariant under all volume preserving diffeomorphisms. We also prove that if k·k is, additionally, not equivalent to k · k∞, then the induced ...Journal Article -
Comparative genomics and disorder prediction identify biologically relevant SH3 protein interactions
(2005)PLoS Computational BiologyProtein interaction networks are an important part of the post-genomic effort to integrate a part-list view of the cell into system-level understanding. Using a set of 11 yeast genomes we show that combining comparative genomics and secondary structure information greatly increases consensus-based prediction of SH3 targets. Benchmarking of our method against positive and negative standards gave 83% accuracy with 26% coverage. The concept ...Journal Article -
Characterization of the rapid expansion of supercritical solutions by Fourier transform infrared spectroscopy in situ
(2005)Review of Scientific InstrumentsA new apparatus for the in situ characterization of the rapid expansion of supercritical solutions (RESS) by Fourier transform infrared spectroscopy is presented. The infrared characterization is complemented by particle sizing with a scanning mobility particle sizer, by three-wavelengths-extinction measurements, and by scanning electron microscopy. Several examples show that a wide range of information about ...Journal Article -
Control of Deep Space Formation Flying Spacecraft; Relative Sensing and Switched Information
(2005)Journal of Guidance, Control, and DynamicsSpacecraft formations in deep space can be specified in terms of the relative spacecraft positions and absolute spacecraft orientations. Accurate absolute position measurements are not available and a formation control design approach, based on relative position information, is presented. This approach exploits the redundancy inherent in a relative position specification to develop a family of equivalent control topologies for optimal ...Journal Article