Two Cases of Cardiac Arteriovenous Malformation Complicated by a Local Angioproliferative Process

Vascular malformations of the heart are extremely rare with only a few cases of the arteriovenous type of vascular malformation (AVM) reported. We investigated the pathology of two additional cases, which were complicated by the occurrence of a local vasoproliferative response of immature but benign vessels. We suppose that the mass forming effect of this vasoproliferative response, which has also been reported recently as a complication of congenital AVM elsewhere in the body, has significantly contributed to the onset of symptoms and ultimate death of both patients

Distributed database management systems : Architectural design choices for the cloud

Cloud computing has changed the way we used to exploit software and systems. The two decades’ practice of architecting solutions and services over the Internet has just revolved within the past few years. End users are now relying more on paying for what they use instead of purchasing a full-phase license. System owners are also in rapid hunt for business profits by deploying their services in the Cloud and thus maximising global outreach and minimising overall management costs. However, deploying and scaling Cloud applications regionally and globally are highly challenging. In this context, distributed data management systems in the Cloud promise rapid elasticity and horizontal scalability so that Cloud applications can sustain enormous growth in data volume, velocity, and value. Besides, distributed data replication and rapid partitioning are the two fundamental hammers to nail down these challenges. While replication ensures database read scalability and georeachability, data partitioning favours database write scalability and system-level load balance. System architects and administrators often face difficulties in managing a multi-tenant distributed database system in Cloud scale as the underlying workload characteristics change frequently. In this chapter, the inherent challenges of such phenomena are discussed in detail alongside their historical backgrounds. Finally, potential way outs to overcome such architectural barriers are presented under the light of recent research and development in this area