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Observation of the hadronic final state charge asymmetry in high Q2 deep-inelastic scattering at HERA
(2009)Physics Letters BA first measurement is presented of the charge asymmetry in the hadronic final state from the hard interaction in deep-inelastic ep neutral current scattering at HERA. The measurement is performed in the range of negative squared four momentum transfer 100 < Q 2 < 8000 GeV 2. The difference between the event normalised distributions of the scaled momentum, x p, for positively and negatively charged particles, measured in the current region ...Journal Article -
The CMS barrel calorimeter response to particle beams from 2 to 350 GeV/c
(2009)The European Physical Journal CThe response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c has been measured. To our knowledge, this is the widest range of momenta in which any calorimeter system has been studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. The analysis of the differences in calorimeter ...Journal Article -
Strangeness production at low Q2 in deep-inelastic ep scattering at HERA
(2009)The European Physical Journal CThe production of neutral strange hadrons is investigated using deep-inelastic scattering events measured with the H1 detector at HERA. The measurements are made in the phase space defined by the negative four-momentum transfer squared of the photon 2<Q 2<100 GeV2 and the inelasticity 0.1<y<0.6. The K s 0 and Λ(Λ¯) production cross sections and their ratios are determined. K s 0 production is compared to the production of charged particles ...Journal Article -
Events with isolated leptons and missing transverse momentum and measurement of W production at HERA
(2009)The European Physical Journal CEvents with high energy isolated electrons, muons or tau leptons and missing transverse momentum are studied using the full e ± p data sample collected by the H1 experiment at HERA, corresponding to an integrated luminosity of 474 pb−1. Within the Standard Model, events with isolated leptons and missing transverse momentum mainly originate from the production of single W bosons. The total single W boson production cross section is measured ...Journal Article -
A study of quasi-elastic muon neutrino and antineutrino scattering in the NOMAD experiment
(2009)The European Physical Journal CWe have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions (ν μ n→μ − p and ν¯μp→μ+n ) using a set of experimental data collected by the NOMAD Collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly carbon) normalizing it to the total ν μ ( ν¯μ ) charged-current cross section. The results for the flux-averaged QEL cross sections in the (anti)neutrino ...Journal Article -
Measurement of the inclusive ep scattering cross section at low Q (2) and x at HERA
(2009)The European Physical Journal CA measurement of the inclusive ep scattering cross section is presented in the region of low momentum transfers, 0.2 GeV2 ≤Q 2≤12 GeV2, and low Bjorken x, 5⋅10−6≤x≤0.02. The result is based on two data sets collected in dedicated runs by the H1 Collaboration at HERA at beam energies of 27.6 GeV and 920 GeV for positrons and protons, respectively. A combination with data previously published by H1 leads to a cross section measurement of a ...Journal Article -
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Distinct Roles of Non-Canonical Poly(A) Polymerases in RNA Metabolism
(2009)PLoS GeneticsTrf4p and Trf5p are non-canonical poly(A) polymerases and are part of the heteromeric protein complexes TRAMP4 and TRAMP5 that promote the degradation of aberrant and short-lived RNA substrates by interacting with the nuclear exosome. To assess the level of functional redundancy between the paralogous Trf4 and Trf5 proteins and to investigate the role of the Trf4-dependent polyadenylation in vivo, we used DNA microarrays to compare gene ...Journal Article -
Imprinting of the polycomb group gene MEDEA serves as a ploidy sensor in Arabidopsis
(2009)PLoS GeneticsBalanced maternal and paternal genome contributions are a requirement for successful seed development. Unbalanced contributions often cause seed abortion, a phenomenon that has been termed “triploid block.” Misregulation of imprinted regulatory genes has been proposed to be the underlying cause for abnormalities in growth and structure of the endosperm in seeds with deviating parental contributions. We identified a mutant forming unreduced ...Journal Article -
The Drosophila SH2B family adaptor Lnk acts in parallel to chico in the insulin signaling pathway
(2009)PLoS GeneticsInsulin/insulin-like growth factor signaling (IIS) plays a pivotal role in the regulation of growth at the cellular and the organismal level during animal development. Flies with impaired IIS are developmentally delayed and small due to fewer and smaller cells. In the search for new growth-promoting genes, we identified mutations in the gene encoding Lnk, the single fly member of the SH2B family of adaptor molecules. Flies lacking lnk ...Journal Article