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Additional file 1. Calculation of torsional shear angle from basal and apical slices.

The dissertation consists of three studies concerning the research fields of evaluating volatility and correlation forecasts as well as modeling of tail dependence. Based on theoretical discussions and empirical studies the methods for modeling the time-varying volatilities and dependence for the financial market data are evaluated. The first study evaluates the volatility forecasts with the basic generalized conditional autoregressive heteroskedasticity (GARCH) model and its asymmetric extensions. The concepts of loss function and model confidence set (MCS) are introduced. The realized volatility is used as benchmark. The main results of Brownlees et al. (2011) can be confirmed and extended. In particular, the one-step forecasts achieve significantly lower average losses than the multi-step forecasts in times of crises. The difference between the one-step and the multi-step forecasts in pre-crisis times is relatively small. The evaluation results demonstrate the strong forecasting performance of the asymmetric model variants. The second study evaluates the multivariate correlation forecasts. The Baba-Engle-Kraft-Kroner (BEKK) model of Engle and Kroner (1995) is compared with the dynamic conditional correlation (DCC) model of Engle (2002). Using a two-stage estimation method, the DCC model is well suited for large correlation matrices. In contrast, the more flexible BEKK model suffers from the curse of dimensionality. The evaluation is based on the class of asymmetric loss functions proposed by Komunjer and Owyang (2012). The results show that the BEKK model cannot better predict the correlations than the simpler DCC model in the trivariate system. Therefore, the application of the DCC model appears to be superior. The third study leads to a flexible approach which separates the univariate marginal distributions from the joint distribution. The different copula functions are presented and the corresponding tail dependence is calculated. The empirical analysis compares different copula functions with a non-parametric approach and three time-dependent approaches. The results show noticeable reactions of tail dependence to the major financial market events. In addition, the lower tail dependence dominates over time. This can be interpreted in a way that joint losses occur more frequently than joint gains.

Aims To evaluate the efficacy and safety of transcatheter closure of very large secundum atrial septal defects (ASD) with long-term follow-up results. Methods and results From June, 2001 to June, 2008, 74 patients diagnosed as secundum atrial septal defect with a diameter more than 30 mm were enrolled in the study. Percutaneous closure of ASDs were attempted by using the Domestic Shanghai ASD-O guided by transthoracic echocardiography (TTE). For the group of the 74 patients, 68 of them are adults. The closure was successful in 71/74 patients (96%). The mean diameter of the device was 38.2±2.73 mm. During the follow-up, complete closure could be achieved in 100% of patients. 7 adverse events (9.9%) were reported. Most adverse events were categorised as minor and there was one major adverse events (1.4%). Conclusion Transcatheter device closure is an effective management option for patients with very large ASD. Serious complications were rare.