Static Analysis of Aspect Interaction and Composition in Component Models

International audienceComponent based software engineering and aspect orientation are claimed to be two complementary approaches. While the former ensures the modularity and the reusability of software entities, the latter enables the modularity of crosscutting concerns that cannot be modularized by regular components. Nowadays, several approaches and frameworks are dedicated to integrate aspects into component models. However, when several aspects are woven, interferences may appear which results on undesirable behaviors. The contribution of this paper is twofold. First, we show how aspectualized component models can be formally modeled in Uppaal model checker in order to detect potential interferences among aspects. Second, we provide an extendible catalog of composition operators used for aspect composition. We illustrate our general approach with an airport Internet service example

Managing the Context Interaction Problem: A Classification and Design Space of Conflict Resolution Techniques in Dynamically Adaptive Software Systems

The context interaction problem occurs in dynamically adaptive software systems whenever adaptations to different contexts provide incompatible behaviour, as they were not foreseen to occur simultaneously. Several strategies have been proposed to resolve such conflicts when they occur. This paper surveys a number of such conflict resolution strategies, and proposes a design space in which to classify, compare, and explain the differences between them

Inhibition of cyclooxygenase-2 impacts chondrocyte hypertrophic differentiation during endochondral ossification

Skeletogenesis and bone fracture healing involve endochondral ossification, a process during which cartilaginous primordia are gradually replaced by bone tissue. In line with a role for cyclooxygenase-2 (COX-2) in the endochondral ossification process, non-steroidal anti-inflammatory drugs (NSAIDs) were reported to negatively affect bone fracture healing due to impaired osteogenesis. However, a role for COX-2 activity in the chondrogenic phase of endochondral ossification has not been addressed before. We show that COX-2 activity fulfils an important regulatory function in chondrocyte hypertrophic differentiation. Our data reveal essential cross-talk between COX-2 and bone morphogenic protein-2 (BMP-2) during chondrocyte hypertrophic differentiation. BMP-2 mediated chondrocyte hypertrophy is associated with increased COX-2 expression and pharmacological inhibition of COX-2 activity by NSAIDs (e.g., Celecoxib) decreases hypertrophic differentiation in various chondrogenic models in vitro and in vivo, while leaving early chondrogenic development unaltered. Our findings demonstrate that COX-2 activity is a novel factor partaking in chondrocyte hypertrophy in the context of endochondral ossification and these observations provide a novel etiological perspective on the adverse effects of NSAIDs on bone fracture healing and have important implications for the use of NSAIDs during endochondral skeletal development