Driven quadrature and spin squeezing in a cavity-coupled ensemble of two-level states

The generated magnitude of quadrature squeezing in a cavity-coupled ensemble, which is continuously driven using a coherent off-axis field, is theoretically explored. Using a truncated set of equations of motion derived from a Dicke Hamiltonian, steady-state quadrature squeezing of the cavity field is numerically calculated to approach a limit of -3dB, while frequency-modulated quadrature squeezing approaches a limit of -14dB, in the absence of pure dephasing and as a function of the ensemble's size and detuning. The impact of pure dephasing on steady-state quadrature squeezing is shown to be mitigated by increased detuning of the driving field, while frequency-modulated squeezing is only shielded in a regime where the cumulative coupling and driving rates are in excess of the pure-dephasing rate. Spin-squeezed entanglement is also calculated to occur simultaneously with weakly driven frequency-modulated quadrature squeezing

Validation of the 6-Month GRACE Score in Predicting 1-Year Mortality of Patients With Acute Coronary Syndrome Admitted to the Arabian Gulf Hospitals

Acute coronary syndromes (ACS) are the most common cardiovascular diseases and are associated with a significant risk of mortality and morbidity. The Global Registry of Acute Coronary Events (GRACE) risk score postdischarge is a widely used ACS prediction model for risk of mortality (low, intermediate, and high); however, it has not yet been validated in patients from the Arabian Gulf. This prospective multicenter study (second Gulf Registry of Acute Coronary Events) provides detailed information of the GRACE risk score postdischarge in patients from the Arabian Gulf. Its prognostic utility was validated at 1-year follow-up in over 5000 patients with ACS from 65 hospitals in 6 Arabian Gulf countries (Bahrain, Saudi Arabia, Qatar, Oman, United Arab Emirates, and Yemen). Overall, the goodness of fit (Hosmer and Lemeshow statistic P value = .826), calibration, and discrimination (area under the receiver operating characteristic curve = 0.695; 95% confidence interval: 0.668-0.722) were good. The GRACE risk score postdischarge can be used to stratify 1 year mortality risk in the Arabian Gulf population; it does not require further calibration and has a good discriminatory ability.Gulf RACE-2 is a Gulf Heart Association (GHA) project and was financially supported by the GHA, Sanofi-Aventis, and the Deanship of Scientific Research at King Saud University, Riyadh, Saudi Arabia (Research group number: RG-1436-013). L.F.K. is funded by an Endeavour Postgraduate Scholarship (#3781_2014), an Australian National University Higher Degree Scholarship, and a Fondo para la Innovacio´n, Ciencia y Tecnologı´a Scholarship (#095-FINCyTBDE-2014)