The STF2p Hydrophilin from Saccharomyces cerevisiae Is Required for Dehydration Stress Tolerance

The yeast Saccharomyces cerevisiae is able to overcome cell dehydration; cell metabolic activity is arrested during this period but restarts after rehydration. The yeast genes encoding hydrophilin proteins were characterised to determine their roles in the dehydration-resistant phenotype, and STF2p was found to be a hydrophilin that is essential for survival after the desiccation-rehydration process. Deletion of STF2 promotes the production of reactive oxygen species and apoptotic cell death during stress conditions, whereas the overexpression of STF2, whose gene product localises to the cytoplasm, results in a reduction in ROS production upon oxidative stress as the result of the antioxidant capacity of the STF2p protein

Limits to the muon flux from WIMP annihilation in the center of the Earth with the AMANDA detector

A search for nearly vertical up-going muon-neutrinos from neutralino annihilations in the center of the Earth has been performed with the AMANDA-B10 neutrino detector. The data sample collected in 130.1 days of live-time in 1997, ~10^9 events, has been analyzed for this search. No excess over the expected atmospheric neutrino background is oberved. An upper limit at 90% confidence level on the annihilation rate of neutralinos in the center of the Earth is obtained as a function of the neutralino mass in the range 100 GeV-5000 GeV, as well as the corresponding muon flux limit.Comment: 14 pages, 11 figures. Version accepted for publication in Physical Review

New results from the Antarctic Muon And Neutrino Detector Array

We present recent results from the Antarctic Muon And Neutrino Detector Array (AMANDA) on searches for high-energy neutrinos of extraterrestrial origin. We have searched for a diffuse flux of neutrinos, neutrino point sources and neutrinos from GRBs and from WIMP annihilations in the Sun or the center of the Earth. We also present a preliminary result on the first energy spectrum above a few TeV for atmospheric neutrinos.Comment: 8 pages, 8 figures, to be published in Nuclear Physics B (Proceedings Supplement): Proceedings of the XXIst International Conference on Neutrino Physics and Astrophysics, Paris, June 14-19, 200

Flux limits on ultra high energy neutrinos with AMANDA-B10

Abstract Data taken during 1997 with the AMANDA-B10 detector are searched for a diffuse flux of neutrinos of all flavors with energies above 10 16 eV. At these energies the Earth is opaque to neutrinos, and thus neutrino induced events are concentrated at the horizon. The background are large muon bundles from down-going atmospheric air shower events. No excess events above the background expectation are observed and a neutrino flux following E À2 , with an equal mix of all flavors, is limited to E 2 U(10 15 eV < E < 3 · 10 18 eV) 6 0.99 · 10 À6 GeV cm À2 s À1 sr À1 at 90% confidence level. This is the most restrictive experimental bound placed by any neutrino detector at these energies. Bounds to specific extraterrestrial neutrino flux predictions are also presented. Ó 2004 Elsevier B.V. All rights reserved. PACS: 95.55.Vj; 95.85.Ry; 96.40.T