Emer Gallagher

Multislice CT virtual intravascular endoscopy for abdominal aortic aneurysm stent grafts

PURPOSE To investigate the optimal scanning protocols of multislice computed tomographic (CT) angiography in aortic stent graft placement observed on virtual intravascular endoscopy (VIE). MATERIALS AND METHODS A human aorta phantom was built with a commercial aortic stent graft placed in situ. The phantom was housed in a perspex container and filled with contrast medium with CT attenuation similar to that used in the patients abdominal scanning. CT was performed with a four-slice multislice CT scanner with section thickness of 1.3 mm, 2 mm, and 3.2 mm, pitch of 0.75, 1, and 1.5, and reconstruction interval of 50% overlap and no overlap. Stair-step artifacts were quantified by measuring the SD of signal intensity on surfaced shaded VIE images in three different locations: superior mesenteric artery (SMA), renal ostium, and aortic aneurysm. RESULTS Image quality of VIE images was independent of section thickness and pitch values in the level of renal ostium and aortic aneurysm (P >.05), whereas it was determined by the section thickness and pitch in the level of SMA (P <.05). Aortic branch origin became irregular or distorted when section thickness increased to 3.2 mm or pitch reached 1.5. CONCLUSION A scanning protocol of section thickness of 2 mm, pitch 1, and reconstruction interval of 1 mm is recommended in aortic stent graft placement because it allows fewer stair-step artifacts and better visualization of the aortic stent wires observed on VIE.

Northern Ireland’s property market bubble: a preliminary analysis

This article applies a recursive regression technique developed by Phillips and Yu (2011) to examine recent property market movements in both the Republic of Ireland and Northern Ireland in the context of an asset market bubble. This technique, which interprets explosiveness in the price series as evidence of the existence of a bubble, provides a method for identifying not only bubble behaviour but also a dating mechanism. Statistically significant bubble characteristics are identified in both series. For the Republic of Ireland, a prolonged period of explosiveness is detected ranging from 1996Q2 to 2007Q2. Interestingly, the explosiveness is stronger in the late 1990s and early 2000s. For Northern Ireland, the analysis identifies a short yet intense bubble when the market in the Republic had matured, extending from 2005Q3 to 2009Q1 and reaching a peak in 2007Q2. These results taken together indicate the possibility of a spillover effect between the two regions; however, further research to investigate this possibility is necessary.

Encouraging technology transfer among SMEs in the northern periphery of Europe

Central to the EU regional development strategy is the idea that cohesion funding will allow lagging regions to develop their capacity so that they can develop their R&D to levels that can be funded by Framework. Using a European funded (ERDF) NPP project – MicrE as a case study, this paper considers how, through a transnational programme, this might work in practice. MicrEs main aim was to provide a service to develop and promote innovative small-scale renewable energy solutions for rural small and medium-sized enterprises (SMEs) in the northern periphery of Europe. Concentrating on Northern Ireland, this paper provides a micro and macro-level assessment of the key challenges associated with adopting renewable energy technologies by SMEs; and the future development of public policy aimed at developing SME capacity by encouraging knowledge transfer and supporting their R&D efforts.