Context-Prediction models to identify healthy individuals at high risk of cardiovascular disease have limited accuracy. A low ankle brachial index is an indicator of atherosclerosis and has the potential to improve prediction.Objective-To determine if the ankle brachial index provides information on the risk of cardiovascular events and mortality independently of the Framingham Risk Score and can improve risk prediction.
In this population-based study, PVT was found to be more common than indicated by previous clinical series. The markedly excess risk in cirrhosis and hepatic carcinoma should warrant an increased awareness in these patients for whom prospective studies of directed intervention might be considered.
Between 1971 to 1986 and 2000 to 2004, the incidence of rAAA increased significantly, despite a 100% increase in elective repairs and notwithstanding a potential for bias towards underestimation due to lower autopsy rates in recent years. The reason behind this increase is unclear, and further studies are needed to identify risk groups for direction of effective prevention and screening.
We analyze atom-atom correlations in the s-wave scattering halo of two colliding condensates. By developing a simple perturbative approach, we obtain explicit analytic results for the collinear ͑CL͒ and back-toback ͑BB͒ correlations corresponding to realistic density profiles of the colliding condensates with interactions. The results in the short-time limit are in agreement with the first-principles simulations using the positive-P representation and provide analytic insights into the experimental observations of Perrin et al. ͓Phys Experiments with colliding Bose-Einstein condensates ͑BECs͒ ͓1,2͔ are currently attracting considerable attention in the field of ultracold quantum gases ͓3-11͔. A recent breakthrough in this area is the direct detection ͓2͔ of atomatom pair correlations in the s-wave scattering halo formed in the collision of metastable helium ͑ 4 He * ͒ condensates. Experimental advances like this pose increasingly demanding challenges to theory due to the need to provide quantitatively accurate descriptions in realistic parameter regimes.Theoretical developments are taking place on two fronts, using ͑i͒ numerical techniques based on stochastic phasespace methods ͑such as the first-principles simulations in the positive-P representation ͓9,11͔ or approximate simulations based on the truncated Wigner-function expansion ͓8͔͒, and ͑ii͒ analytic methods such as the Bogoliubov theory ͓5-7͔, undepleted source approximation ͓4,11͔, and a simple Gaussian ansatz ͓10͔. ͑The analytic methods often represent extensions of quantum optics approaches describing closely related systems of parametric down-conversion and four-wave mixing ͓12͔.͒ Despite these developments, the existing numerical techniques still fall short of fully describing the experimental measurements of Ref. ͓2͔, whereas the approximations of the analytic methods are usually too severe to lead to full quantitative agreement with the experiments.In this Rapid Communication, we develop an alternative analytic scheme to obtain explicit results for atom-atom correlations in condensate collisions. The scheme is rather simple, yet it compares surprisingly well with the exact positive-P simulations in the short-time limit. The main advantages of the method are the analytic transparency and the fact that it can model realistic density profiles of the colliding condensates with interactions. This is important for addressing the role of mode mixing due to the inhomogeneity of trapped atomic clouds, which is the strongest effect that influences the strengths and the width of atom-atom correlations. Our results may also have implications for future experiments aimed at producing relative atom number squeezing ͓11,13-15͔ and Einstein-Podolsky-Rosen correlations ͓16,17͔.Additionally, we perform first-principles positive-P simulations of the collision dynamics and analyze the widths of the collinear ͑CL͒ and back-to-back ͑BB͒ correlations as per measurements of Ref. ͓2͔. These characterize, respectively, the pair correlations between the scattered atoms propa...
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