Gauge-invariant nonlocal quark condensates in QCD: a new interpretation of the lattice results

We study the asymptotic short-distance behaviour as well as the asymptotic large-distance behaviour of the gauge-invariant quark-antiquark nonlocal condensates in QCD. A comparison of some analytical results with the available lattice data is performed.Comment: Talk given at the ``XVIIth International Symposium on Lattice Field Theory'', Pisa (Italy), June 29th - July 3rd, 1999 (LATTICE 99); 3 pages, LaTeX file, uses ``espcrc2.sty''; a mistake in Eq. (17) corrected plus other minor change

Real-time in vivo imaging of the beating mouse heart at microscopic resolution.

Real-time imaging of moving organs and tissues at microscopic resolutions represents a major challenge in studying the complex biology of live animals. Here we present a technique based on a novel stabilizer setup combined with a gating acquisition algorithm for the imaging of a beating murine heart at the single-cell level. The method allows serial in vivo fluorescence imaging of the beating heart in live mice in both confocal and nonlinear modes over the course of several hours. We demonstrate the utility of this technique for in vivo optical sectioning and dual-channel time-lapse fluorescence imaging of cardiac ischaemia. The generic method could be adapted to other moving organs and thus broadly facilitate in vivo microscopic investigations