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Subtitle Coronary atherosclerosis and hypertension.Background A plethora of evidence showing that there are certain distinctive morphological features of coronary atherosclerosis, includingthin-cap fibroatheroma, focal severe stenosis, superficial calcified nodules, diffuse non-stenotic plaques, and so forth. However, it is still not certain whether hypertension, a well-established coronary risk factor, is associated with all these different features.Methods This study included 224 consecutive patients underwent multidetector computed tomography before diagnostic coronary angiography. 5 atherosclerotic parameters, including severity score, extent score, calcium volume score, number of coronary arteries with !50% luminal stenosis, and number of plaques with !70% luminal stenosisof the entire coronary tree and individual coronary arteries were assessed. Hypertension was defined as patients being treated for hypertension or having a seated systolic blood pressure of !140 mm Hg or a diastolic blood pressure of !90 mm Hg.Results Among the 5 atherosclerotic parameters, hypertension was independently associated with the severity score (p ¼ 0.026) and the extent score (p ¼ 0.004) after adjustments for conventional risk factors, body-mass index, waist circumference, C-reactive protein, and intra-abdominal visceral fat area. Among the three coronary arteries, hypertension was significantly correlated with both the severity and extent scores of each individual coronary artery, except the severity score of the right coronary artery. However, systolic, diastolic, pulse pressure and heart rate measured at admission were not associated with all 5 parameters of coronary atherosclerosis.Conclusions Hypertension is more closely associated with less advanced and less vulnerable features of coronary atherosclerosis. This observation is consistent with the concept that hypertension is a risk factor for coronary atherosclerosis, rather than a trigger for myocardial infarction.

In this paper, we use the replica method originally developed in statistical physics to investigate the asymptotic sumrate of a Gaussian antenna-array-based multiple-input multipleoutput (MIMO) multiple-access wireless channel having spatial correlations at both the transmitters and the receiver. The asymptotic solution is not only rigorously valid for systems with large array sizes, but it also produces highly accurate ergodic results for systems with only a few antenna elements at each transmitter and receiver. Furthermore, with the asymptotic solution, we provide an efficient iterative water-filling algorithm to determine the optimum transmit signal covariance matrices when only the slow-varying channel spatial covariance information is available.