The idea that somemedical procedures are unnecessary and can do more harm than good is as old as medicine itself. In Mesopotamia 38 centuries ago, Hammurabi proclaimed a law threatening overzealous surgeons with the loss of a hand or an eye. In 1915, at the height of a surgical vogue for prophylactic appendicectomy, Ernest Codman offended his Boston colleagues with a cartoon (figure⇓) mocking t...

In November 2007 the international competition DARPA Urban Challenge took place on the former George Airforce Base in Victorville, California to significantly promote the research and development on autonomously driving vehicles for urban environments. In the final race only eleven out of initially 89 competitors participated and “Boss” from Carnegie Mellon University succeeded. This paper summ...

Background: To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS). Methods: Chi-square analysis of weighted data to compare demographic and behavioral data of persons interviewed who provided specimens for anonymous testing with those who did not. Prev...

One of the central questions in theoretical particle physics, since already several decades, has been that of " masses and mixings of the quarks. With the entry of neutrino oscillations into the field, the issue of lepton masses has added a new dimension to the problem. In the literature one finds many models of quark and lepton mass matrices. However, the mass and mixing problems remain unsolv...

We review the present status of QCD corrections to weak decays beyond the leading logarithmic approximation including particle-antiparticle mixing and rare and CP violating decays. After presenting the basic formalism for these calculations we discuss in detail the effective hamiltonians for all decays for which the next-to-leading corrections are known. Subsequently, we present the phenomenolo...

We illustrate the current status of heavy quark physics on the lattice. Special emphasis is paid to the question of systematic uncertainties and to the connection of lattice computations to continuum physics. Latest results are presented and discussed with respect to the progress in methods, statistical accuracy and reliability.

We present a systematic classification of field directions for the string– derived flipped SU(5) model that are D– and F–flat to all orders. Properties of the flipped SU(5) model with field values in these directions are compared to those associated with other flat directions that have been shown to be F–flat to specific finite orders in the superpotential. We discuss the phenomenological Higgs...

Gender has long been recognised as important within environmental issues, but there has been considerable debate over how to conceptualise the gender ^ environment nexus. As feminist theorising around women and gender has changed, so have conceptualisations about gender and environment, leading to a key debate within ecofeminism and related literatures about whether there is an essential or a c...

We calculate the CP–violating effects in the top quark semi–leptonic three body decays induced by the supersymmetric CP–odd phase of the top squark trilinear soft breaking term arg(At). The light top squark mass is assumed to be close to the top quark mass mt̃ ∼ mt. The CP–conserving phase is provided by the χ+ and χ0 cut. We find that the partial rate asymmetry is in the 0.1% level. In the most...