Production of events with hadronic and leptonic final states has been measured in e + e − collisions at centre-of-mass energies of 130–172 GeV, using the OPAL detector at LEP. Cross-sections and leptonic forward-backward asymmetries are presented, both including and excluding the dominant production of radiative Zγ events, and compared to Standard Model… (More)
We have developed a simple, fast, and efficient procedure to detect enteroviruses in water samples. Aliquots of water are subjected to two-step filtration, with the second filter containing a positively charged nylon membrane that holds back virus particles. Viruses thus adsorbed are directly lysed, and RNA is isolated by hybridization to specific… (More)
The cross-section of the ep → e p γ reaction has been measured at Q 2 = 0.33 (GeV/c) 2. The experiment was performed using the electron beam of the MAMI accelerator and the standard detector setup of the A1 Collaboration. The cross-section is analyzed using the low-energy theorem for virtual Compton scattering, yielding a new determination of the two… (More)
One contribution to the time resolution of a scintillation detector is the signal time spread due to path length variations of the detected photons from a point source. In an experimental study a rectangular scintillator was excited by means of a fast pulsed ultraviolet laser at different positions along its longitudinal axis. Timing measurements with a… (More)
6 e pick−up − photo− multpl.
Helicity density matrix elements for inclusive K * (892) 0 mesons from hadronic Z 0 decays have been measured over the full range of K * 0 momentum using data taken with the OPAL experiment at LEP. A preference for occupation of the helicity zero state is observed at all scaled momentum x p values above 0.3, with the matrix element ρ 00 rising to 0.66 ±… (More)
'Patch-clamp' experiments in the cell-attached configuration have shown the existence of three distinct types of ion channels in the plasma membrane of Dictyostelium discoideum. Channels DI (slope conductance 11 pS) and DII (slope conductance 6 pS) promote an outward current at depolarizing voltages. A third ion channel (HI, slope conductance 3 pS) opens… (More)