CORRIGENDUM: Phase transition in the two-dimensional frustrated x-y model: scaling equations
The author establishes scaling equations for the two-dimensional x-y model with weak frustration using the electrostatic analogy of Kosterlitz and Thouless. In the limit of small disorder he finds a shift in the critical temperature Tc(x)-Tc(0)=-(Jx/kB)(2 pi 2- pi /2 ln 2x) and the exponents are unchanged from the pure values.
Two-level systems in a spin-glass model. I. General formalism and two-dimensional model
A spin-glass model with two-dimensional, isotropic spins (XY model) is studied. The model exhibits two-level systems (TLS) which are related to the sense of rotation of the spin direction. The two-dimensional version of the model is equivalent at low temperature to an Ising model with Coulomb interactions (which are logarithmic in two dimensions). However, this long-range effective interaction between TLS may be a special feature of two-dimensional spins. The model depends on a continuous parameter x and can reproduce, in particular, the 'Edwards-Anderson model', the 'Mattis model', and the 'odd model'.
The costs of identifying undiagnosed prostate cancer in asymptomatic men in New Zealand general practice
Background. Screening for prostate cancer (PCa) using the prostate-specific antigen (PSA) test is widespread in New Zealand. 3 informed testing history in 2007–09 were NZ$8887 compared to NZ$13 870 if the men had PSA tests in 2007–09. If we assumed a PSA test involved a full 15-minute general practice consultation, the estimated costs increased to NZ$26 877 per PCa identified. Conclusions. Screening of asymptomatic men for PCa is widely practiced. Most of the costs of screening were incurred in general practice. Calls for men to receive increased information on the harms and benefits of screening will substantially increase the costs. The current costs could be reduced by better targeting of screening.