Prediction of the B{c}{*} mass in full lattice QCD.

By using the highly improved staggered quark formalism to handle charm, strange, and light valence quarks in full lattice QCD, and NRQCD to handle bottom valence quarks, we are able to determine accurately ratios of the B meson vector-pseudoscalar mass splittings, in particular, [m(B{c}{*})-m(B{c})]/[m(B{s}{*})-m(B{s})]. We find this ratio to be 1.15(15), showing the "light" quark mass dependence of this splitting to be very small. Hence we predict m(B{c}{*})=6.330(7)(2)(6) GeV, where the first two errors are from the lattice calculation and the third from existing experiment. This is the most accurate prediction of a gold-plated hadron mass from lattice QCD to date.

Semileptonic decays of d mesons in three-flavor lattice QCD.

We present the first three-flavor lattice QCD calculations for D-->pilnu and D-->Klnu semileptonic decays. Simulations are carried out using ensembles of unquenched gauge fields generated by the MILC Collaboration. With an improved staggered action for light quarks, we are able to simulate at light quark masses down to 1/8 of the strange mass. Consequently, the systematic error from the chiral extrapolation is much smaller than in previous calculations with Wilson-type light quarks. Our results for the form factors at q(2)=0 are f(D-->pi)(+)(0)=0.64(3)(6) and f(D-->K)(+)(0)=0.73(3)(7), where the first error is statistical and the second is systematic, added in quadrature. Combining our results with experimental branching ratios, we obtain the Cabibbo-Kobayashi-Maskawa matrix elements |V(cd)|=0.239(10)(24)(20) and |V(cs)|=0.969(39)(94)(24), where the last errors are from experimental uncertainties.

In vivo characteristics of resistance and cross-resistance of an adriamycin-resistant subline of P388 leukemia.

A subline of P388 leukemia resistant to adriamycin (P388/ADR) was developed by exposure to the drug in vivo. Resistance to adriamycin proved to be a stable characteristic of P388/ADR. There was no significant inhibition of nucleic acid synthesis in P388/ADR cells in vivo following a dose of 10 mg/kg of adriamycin in contrast to a prolonged and complete inhibition, particularly of DNA synthesis, observed in parental sensitive P388 leukemia cells. P388/ADR proved to be completely cross-resistant to a spectrum of anthracycline derivatives. Cross-resistance was observed to nonanthracycline DNA intercalating agents (with the exception of anthramycin), to agents which interfere with mitotic spindle function, and to antineoplastic inhibitors of protein biosynthesis (with the exception of bruceantin). P388/ADR was sensitive to antimetabolites and alkylating agents. Cross-resistance was also observed to several agents (ICRF-159, a terephthalanilide, taxol, lymphosarcin, bouvardin, and a crude extract of Ervatamia hyneana) whose mechanisms of action have not yet been clearly defined. This observation has proved useful in providing a lead for determination of mechanism of action of some of these drugs. The pattern of cross-resistance of a subline of P388 leukemia resistant to daunorubicin, though not studied extensively, appears to be similar to that of P388/ADR.

High-precision lattice QCD confronts experiment.

The recently developed Symanzik-improved staggered-quark discretization allows unquenched lattice-QCD simulations with much smaller (and more realistic) quark masses than previously possible. To test this formalism, we compare experiment with a variety of nonperturbative calculations in QCD drawn from a restricted set of "gold-plated" quantities. We find agreement to within statistical and systematic errors of 3% or less. We discuss the implications for phenomenology and, in particular, for heavy-quark physics.