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A morphing wing is designed to morph to different wing profiles required for different flight regimes. Such a design is based on modules, and discretization of different wing profiles will yield different sets of modules. In this paper, a novel wing module consolidation methodology is developed to consolidate different sets of modules to a common set of modules for a unified modular morphing wing design. Initial wing profiles are created for different flight regimes using an optimization algorithm coupled with a fluid solver. These wing profiles are then smoothened, and used as reference geometries for module discretization. The results of discretized wings are then consolidated using a sensitivity analysis and a weighting function that allows the designer to assign a higher priority to a specific flight regime. A case study, showing the implementation of this methodology for climb, cruise, and descent flight regimes, reveals that the consolidated wing can be morphed to approximate the original wing profiles within reasonable errors. In climb, maximizing the inverse of drag as a performance index showed a 5.4% decrease by obtaining higher drag values, which is not desirable. In cruise, maximizing lift to drag ratio as a performance index, showed a 2.9% increase. Finally, in descent, maximizing C3/2L/CD as a performance index showed a 1.6% decrease. [ABSTRACT FROM AUTHOR]

Summary: We performed a systematic review of the literature to establish whether revascularisation of the left subclavian territory is necessary when this artery is covered by a stent. We retrieved data from 99 studies incorporating 4906 patients. Incidences of left-arm ischaemia (0.0% vs 9.2%, p =0.002) and stroke (4.7% vs 7.2%, p <0.001) were significantly less following revascularisation, although mortality (10.5% vs 3.4%, p =0.032) and endoleak incidence (25.8% vs 12.6%, p =0.008) were increased. No significant differences in spinal-cord ischaemia were seen. Revascularisation may reduce downstream ischaemic complications but can cause significant risk. Indications must be carefully considered on an individual patient basis. [ABSTRACT FROM AUTHOR]

Objective: Free-floating thrombus (FFT) of the carotid artery is a rare condition of currently unknown etiology. Less than 150 cases have been described in the published world literature to date. Design and Setting: We present 6 consecutive cases of carotid FFT, identified prospectively from 5000 carotid duplex scans over a 34-month period in a single tertiary center for vascular surgery. Results: All 6 cases involved the left carotid bifurcation in neurologically symptomatic individuals. In 5 of the 6 cases, FFT occurred in the absence of a significantly stenosing atheromatous plaque and was not associated with an elevation in velocity on duplex. The patients were all treated with surgical thromboendarterectomy, with good result. Conclusions: Duplex imaging can underestimate the degree of stenosis. Free-floating thrombus presents a challenge in diagnosis due to its rapidly evolving nature. The management of FFT by acute thromboendarterectomy appears to be safe and effective in limiting further focal neurological sequelae. [ABSTRACT FROM AUTHOR]