New U(1) Gauge Symmetry of Quarks and Leptons

Instead of anchoring the seesaw mechanism with the conventional heavy right-handed neutrino singlet, a small Majorana neutrino mass may be obtained just as well with the addition of a heavy triplet of leptons per family to the minimal standard model of particle interactions. The resulting model is shown to have the remarkable property of accommodating a new U(1) symmetry which is anomaly-free and may thus be gauged. There are many possible phenomenological consequences of this proposal which may be already relevant in explaining one or two recent potential experimental discrepancies.Comment: minor word changes, to appear in MPL

Regularizing the quark-level σ\sigma model

We show that the finite difference, $-i\pi^2 m^2$, between quadratic and logarithmic divergent integrals $\int d^4p[m^2(p^2-m^2)^{-2}-(p^2-m^2)^{-1}]$, as encountered in the linear $\sigma$ model, is in fact regularization independent.Comment: 9 pages, 2 figures, Latex, to appear in Mod. Phys. Lett.

The impact of diabetes-related complications on healthcare costs: results from the United Kingdom Prospective Diabetes Study (UKPDS Study No. 65)

<b>Aims</b> To develop a model for estimating the immediate and long-term healthcare costs associated with seven diabetes-related complications in patients with Type 2 diabetes participating in the UK Prospective Diabetes Study (UKPDS). <b>Methods</b> The costs associated with some major complications were estimated using data on 5102 UKPDS patients (mean age 52.4 years at diagnosis). In-patient and out-patient costs were estimated using multiple regression analysis based on costs calculated from the length of admission multiplied by the average specialty cost and a survey of 3488 UKPDS patients’ healthcare usage conducted in 1996–1997. <b>Results</b> Using the model, the estimate of the cost of first complications were as follows: amputation £8459 (95% confidence interval £5295, £13 200); non-fatal myocardial infarction £4070 (£3580, £4722); fatal myocardial infarction £1152 (£941, £1396); fatal stroke £3383 (£1935, £5431); non-fatal stroke £2367 (£1599, £3274); ischaemic heart disease £1959 (£1467, £2541); heart failure £2221 (£1690, £2896); cataract extraction £1553 (£1320, £1855); and blindness in one eye £872 (£526, £1299). The annual average in-patient cost of events in subsequent years ranged from £631 (£403, £896) for heart failure to £105 (£80, £142) for cataract extraction. Non-in-patient costs for macrovascular complications were £315 (£247, £394) and for microvascular complications were £273 (£215, £343) in the year of the event. In each subsequent year the costs were, respectively, £258 (£228, £297) and £204 (£181, £255). <b>Conclusions</b> These results provide estimates of the immediate and long-term healthcare costs associated with seven diabetes-related complications

Jets associated with Z^0 boson production in heavy-ion collisions at the LHC

The heavy ion program at the LHC will present unprecedented opportunities to probe hot QCD matter, that is, the quark gluon plasma (QGP). Among these exciting new probes are high energy partons associated with the production of a Z^0 boson, or Z^0 tagged jets. Once produced, Z^0 bosons are essentially unaffected by the strongly interacting medium produced in heavy-ion collisions, and therefore provide a powerful signal of the initial partonic energy and subsequent medium induced partonic energy loss. When compared with theory, experimental measurements of Z^0 tagged jets will help quantify the jet quenching properties of the QGP and discriminate between different partonic energy loss formalisms. In what follows, I discuss the advantages of tagged jets over leading particles, and present preliminary results of the production and suppression of Z^0 tagged jets in relativistic heavy-ion collisions at LHC energies using the Guylassy-Levai-Vitev (GLV) partonic energy loss formalism.Comment: To appear in the proceedings of the 2010 Winter Workshop on Nuclear Dynamics, which was held in Ocho Rios, Jamaica, mon