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Background: A slight increase in revisions for infected joint arthroplasties has been observed in the Nordic countries since 2000 for which the reasons are unclear. However, in 2007 a Swedish study of the timing for prophylactic antibiotics in a random sample of knee arthroplasties found that only 57% of the patients had received the antibiotic during the optimal time interval 45-15 minutes before

In Responsibility From the Margins, David Shoemaker distinguishes three forms of responsibility: attributability, answerability, and accountability. The introduction of various normative competence requirements lends precision to the contrasts that Shoemaker draws between these forms of responsibility. I argue, however, that these competence requirements are less well motivated than Shoemaker supp

The strongest constraint on Vtb presently comes from the 3 × 3 unitarity of the CKM matrix, which fixes Vtb to be very close to one. If unitarity is relaxed, current information from top production at Tevatron still leaves open the possibility that Vtb is sizably smaller than one. In minimal extensions of the standard model with extra heavy quarks, the unitarity constraints are much weaker, and th

We present the latest developments of the MadGraph/MadEvent Monte Carlo event generator and several applications to hadron collider physics. In the current version events at the parton, hadron and detector level can be generated directly from a web interface, for arbitrary processes in the Standard Model and in several physics scenarios beyond it (HEFT, MSSM, 2HDM). The most important additions ar

The ALICE Collaboration has measured the energy dependence of exclusive photoproduction of J / ψ vector mesons off proton targets in ultra–peripheral p–Pb collisions at a centre-of-mass energy per nucleon pair sNN=5.02 TeV. The e + e - and μ + μ - decay channels are used to measure the cross section as a function of the rapidity of the J / ψ in the range - 2.5 < y< 2.7 , corresponding to an energy

The new version of the MadGraph/MadEvent (MG/ME) MC generator is introduced by emphasizing its easy-to-use way of incorporating new models and generating events. As an application, a study of t t production in various scenarios beyond the standard model is presented.

We explore in detail the physics potential of a measurement of the t invariant mass distribution. First, we assess the accuracy of the best available predictions for this observable and find that in the low invariant mass region, the shape is very well predicted and could be used to perform a top mass measurement. Second, we study the effects of a heavy s-channel resonance on the t invariant mass

We present a consistent analysis of the signal as well as the irreducible background for the search of the SM Higgs boson in the ZZ decay channel at the LHC. Soft-gluons effects are resummed up to next-to-leading logarithmic accuracy, and the results are compared to those obtained with fixed order calculations and the MC@NLO event generator. The soft-gluon effects are typically modest but should b

We present the implementation of the dipole subtraction formalism for the real radiation contributions to any next-to-leading order QCD process in the MadGraph/MadEvent framework. Both massless and massive dipoles are considered. Starting from a specific (n+1)-particle process the package provides a Fortran code for all possible dipoles to all Born processes that constitute the subtraction term to

We here present some recent developments of MadGraph/MadEvent since the latest published version, 4.0. These developments include: Jet matching with Pythia parton showers for both Standard Model and Beyond the Standard Model processes, decay chain functionality, decay width calculation and decay simulation, process generation for the Grid, a package for calculation of quarkonium amplitudes, calcul