X-Ray Scanner for Atlas Barrel TRT Modules

X-ray scanners for gain mapping of ATLAS Barrel Transition Radiation Tracker (TRT) modules were developed at Hampton University for quality assurance purposes. Gas gain variations for each straw of the TRT modules were used to decide whether wires should be removed or restrung, and to evaluate overall module quality.Comment: Conference proceeding in the XXIV Physics in Collisions Conference (PIC04), Boston, USA, June 2004, 3 pages, LaTeX, 6 eps figures. MONP0

Knockdown of piRNA pathway proteins results in enhanced Semliki forest virus production in mosquito cells

The exogenous siRNA pathway is important in restricting arbovirus infection in mosquitoes. Less is known about the role of the PIWI-interacting RNA pathway, or piRNA pathway, in antiviral responses. Viral piRNA-like molecules have recently been described following infection of mosquitoes and derived cell lines with several arboviruses. The piRNA pathway has thus been suggested to function as an additional small RNA-mediated antiviral response to the known infection-induced siRNA response. Here we show that piRNA-like molecules are produced following infection with the naturally mosquito-borne Semliki Forest virus in mosquito cell lines. We show that knockdown of piRNA pathway proteins enhances the replication of this arbovirus and defines the contribution of piRNA pathway effectors, thus characterizing the antiviral properties of the piRNA pathway. In conclusion, arbovirus infection can trigger the piRNA pathway in mosquito cells, and knockdown of piRNA proteins enhances virus production

Excited-state absorption in Er:BaY2F8 and Cs3Er2Br9 and comparison with Er:LiYF4

The influence of Excited-State Absorption (ESA) on the green laser transition and the overlap of Ground-State Absorption (GSA) and ESA for 970 nm upconversion pumping in erbium is investigated in Er3+:BaY2F8 and Cs3Er2Br9. Results are compared to Er3+:LiYF4. In Er3+:BaY2F8, a good overlap between GSA and ESA is found at 969 nm in one polarization direction. The emission cross section at 550 nm is a factor of two smaller than in LiYF4. In Cs3Er2Br9, the smaller Stark splitting of the levels shifts the wavelengths of the green emission and ESA from 4I13/2 off resonance. It enhances, however, ground-state reabsorption. The emission cross section at 550 nm is comparable to LiYF4. Upconversion leads to significant green fluorescence from 2H9/2. A significant population of the 4111/2 level and ESA at 970 nm are not present under 800 nm pumping

Thin liquid water clouds: their importance and our challenge

Many clouds important to the Earth’s energy balance contain small amounts of liquid water, yet despite many improvements, large differences in retrievals of their liquid water amount and particle size still must be resolved

Generalized Fock Spaces, New Forms of Quantum Statistics and their Algebras

We formulate a theory of generalized Fock spaces which underlies the different forms of quantum statistics such as ``infinite'', Bose-Einstein and Fermi-Dirac statistics. Single-indexed systems as well as multi-indexed systems that cannot be mapped into single-indexed systems are studied. Our theory is based on a three-tiered structure consisting of Fock space, statistics and algebra. This general formalism not only unifies the various forms of statistics and algebras, but also allows us to construct many new forms of quantum statistics as well as many algebras of creation and destruction operators. Some of these are : new algebras for infinite statistics, q-statistics and its many avatars, a consistent algebra for fractional statistics, null statistics or statistics of frozen order, ``doubly-infinite'' statistics, many representations of orthostatistics, Hubbard statistics and its variations.Comment: This is a revised version of the earlier preprint: mp_arc 94-43. Published versio