An upper limit on the electron-neutrino flux from the HiRes detector

Air-fluorescence detectors such as the High Resolution Fly's Eye (HiRes) detector are very sensitive to upward-going, Earth-skimming ultrahigh energy electron-neutrino-induced showers. This is due to the relatively large interaction cross sections of these high-energy neutrinos and to the Landau-Pomeranchuk-Migdal (LPM) effect. The LPM effect causes a significant decrease in the cross sections for bremsstrahlung and pair production, allowing charged-current electron-neutrino-induced showers occurring deep in the Earth's crust to be detectable as they exit the Earth into the atmosphere. A search for upward-going neutrino-induced showers in the HiRes-II monocular dataset has yielded a null result. From an LPM calculation of the energy spectrum of charged particles as a function of primary energy and depth for electron-induced showers in rock, we calculate the shape of the resulting profile of these showers in air. We describe a full detector Monte Carlo simulation to determine the detector response to upward-going electron-neutrino-induced cascades and present an upper limit on the flux of electron-neutrinos.Comment: 13 pages, 3 figures. submitted to Astrophysical Journa

Simultaneous production of lipases and citric acid from crude glycerol by Yarrowia lipolytica

Badano zdolności drożdży Y. lipolytica Wratislavia 1.31 do produkcji enzymów lipolitycznych w hodowlach fed-batch podczas biosyntezy kwasu cytrynowego. Jako jedyne źródło węgla i energii zastosowano glicerol odpadowy oraz glicerol odpadowy z dodatkiem frakcji glicerynowej. W hodowli z glicerolem odpadowym otrzymano lipazy o wysokiej aktywności wobec tributyryny (4,7 UZT mL-1 i maślanu p-nitrofenolu 2.8 10-4 UzpNPB mL-1.A purpose of the study was to determine the ability of yeast Y. lipolyt ca Wratislavia 1.31 to produce lipases in fed-bath cultures in mediui containing raw glycerol and raw glycerol together with glycerol fra< tion.as a carbon sources during citric acid biosynthesis. A higher, enzi matic activity was observed in medium containing only raw glycen 4.7 UZT mL-1 and 2.8 10-4 UzpNPB mL-1with tributyrin and p-n tro-phenyl butyrate, respectively