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Direct communication among vehicles, namely vehicle-to-vehicle (V2V), as part of vehicle-to-everything (V2X) system, will enable most of the upcoming Connected and Autonomous Vehicles (CAVs) applications. Nevertheless, the challenging requirements imposed by the vehicular environment necessitate advanced control mechanisms. Traditional Radio Access Networks (RANs) lack the necessary flexibility to address these control needs. The emerging Open RAN (O-RAN) concept offers a promising solution for orchestrating the V2X network. However, the seamless integration of these ecosystems remains an unresolved challenge. This article promotes a novel integration architecture that ensures the V2X control within O-RAN. We propose a novel architecture that establishes a low frequencies O-RAN-based control plane to ensure reliable and efficient multi-hops connectivity among CAVs at millimeter wave (mmWave). To examine and test the technological feasibility of this integrated architecture, we extend current Network Simulator 3 (ns-3) modules, leading to a simulation framework for experimenting with O-RAN-empowered V2X system. Such an integrated framework is used to show the benefits in a specific V2V challenge: link and relays selection. This case study serves as a practical example of a new O-RAN solution that effectively addresses the challenges of V2X communications. Numerical results showcase the improved reliability up to 60% of the proposed xApp-controlled V2V network, with low latency and negligible overhead, when compared to distributed and unmanaged solutions, supporting the viability of the proposed architecture.

Edge computing has been recently introduced to bring computational capabilities closer to end-users of modern network-based services, supporting existing and future delay-sensitive applications by effectively addressing the high propagation delay issue that affects cloud computing. However, the problem of efficiently and fairly managing the system resources presents particular challenges due to the limited capacity of both edge nodes and wireless access networks and the heterogeneity of resources and services’ requirements. To this end, we propose a techno-economic market where service providers act as buyers, securing both radio and computing resources to execute their associated end-users’ jobs while being constrained by a budget limit. We design an allocation mechanism that employs convex programming to find the unique market equilibrium point that maximizes fairness while ensuring that all buyers receive their preferred resource bundle. Additionally, we derive theoretical properties that confirm how the market equilibrium approach strikes a balance between fairness and efficiency. We also propose alternative allocation mechanisms and give a comparison with the market-based mechanism. Finally, we conduct simulations to numerically analyze and compare the performance of the mechanisms and confirm the market model's theoretical properties.

Doppler echocardiographic variables were sought for predicting the third and fourth heart sounds, as documented by phonocardiography. Phonocardiographic recordings of gallop sounds and Doppler echocardiographic investigations of mitral inflow and pulmonary venous flow were evaluated in 85 subjects by discriminant and multiple regression analysis. Of 85 subjects 47% had a third sound and 72% a fourth sound, evaluated by phonocardiography. A correct identification of 85% subjects with, and 82% without, the third sound was possible by discriminant analysis using the ratio of peak early diastolic to peak atrial mitral flow velocity (FV), the interval from peak ECG R wave to peak early diastolic mitral FV, and the early diastolic mitral FV deceleration time. At the observed prevalence of the third heart sound (47%), the predictive positive value was 81% and the predictive negative value was 86%. A correct identification of 72% of the subjects with, and 83% without, a fourth sound was possible by discriminant analysis using the ratio of peak early diastolic to peak atrial mitral FV, the interval between the end of atrial mitral FV and the peak ECG R wave, and the duration of pulmonary venous reverse FV at atrial systole. At the observed prevalence of the fourth heart sound (72%) the predictive positive value was 92% and the predictive negative value was 54%. By multiple regression analysis, up to 50% of the amplitude of both gallop sounds was predictable by a combination of Doppler echocardiographic variables.

Echocardiographic demonstration of systolic anterior motion of the mitral valve was seen in a 17 year old patient after the Mustard operation for d-transposition of the great arteries with intact ventricular septum. An increased Row velocity was measured by continuous wave Doppler echocardiography in the left ventricular outflow tract corresponding to an estimated peak gradient of 46 mm Hg. The presence of such a gradient had been shown earlier by the postoperative cardiac catheterization.