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Background Vascular graft infection with anastomotic dehiscence requires immediate surgical intervention to preserve life and limb. We present our experience of using the Omniflow® II biosynthetic vascular prosthesis (LeMaitre Vascular) in the emergency repair of vascular graft dehiscence at the femoral anastomosis. Methods A retrospective review of consecutive patients presenting with femoral anastomotic dehiscence in a single centre was conducted. All patients were revascularized using an in situ Omniflow II graft. Patient demographics, affected graft type, microbiology, and antibiotic regimes were documented. Primary outcome measures were limb salvage, patency rates, and mortality. Results Five patients presented with acute femoral false aneurysm and four of five with significant hemorrhage. Infected grafts included one aortobifemoral, two femoral crossover, one axillobifemoral, and one infrainguinal reversed vein graft. All were revascularized with an in situ Omniflow II graft following the excision of the infected graft material. The median followup was 50 months. Limb salvage was achieved in 8 of 9 threatened limbs, and none required further intervention for re-infection. One graft occluded at 5 months. Two of five patients died during followup (one at 12 months, one at 50 months). Conclusions Omniflow II provides a useful “off-the-shelf” conduit for the urgent revascularization of infected femoral dehiscence.

The damage of a Hadfield steel crossing in a railway turnout due to wheel rolling impact passages is investigated numerically. A three dimensional elastic–plastic finite element model has been developed by taking into account non-linear material properties, dynamic wheel impact and wheel–crossing contact. The effects of wheel velocity on the damage and deformation of the crossing is analysed. In the present study, four rolling velocities of the wheel, i.e., 50 km/h, 100 km/h, 150 km/h, and 200 km/h were chosen. The wheel exhibits elastic material behaviour, whereas the crossing exhibits elastic–plastic material behaviour. To represent the damage and deformation behaviours of the crossing, non-linear dynamic work hardening is further included in the calculation. Dynamic stress and strain in the crossing were obtained by the explicit finite element method, including the maximum von Mises stress, the maximum strain, the maximum horizontal stress, perpendicular stress and parallel stress. The snake-like motion of the wheel rolling on the crossing was verified by the simulation; in the meantime, there is a significant impact load on the nose rail, which caused a big von Mises stress in the nose rail. The big von Mises stress is the main reason for the nose rail fatigue spalling. The maximum von Mises stress and maximum strain in the nose rail increase with the train speed increasing. The study provides a method for the further research on the fatigue and the wear behaviours of railway crossings.

Highway construction has been played an important role in Chinese economic development. A good design was a key factor to a successful project, and at the same time, the geometric parameters and mechanical parameters of asphalt pavement both were of great weight. In this paper, a model of semi-rigid base and asphalt pavement was established, and load response was calculated with BISAR on base of three-layer system, comparison of impact of different parameters on the response was carried out to get the discipline, and this will help the designers to optimize design.

An open-ended dielectric resonator method and experimental apparatus for measuring microwave surface resistance of the high Tc superconducting thin films are reported. Making use of two sapphire rods the quality factor related to the losses of the resonator except its superconducting part can be evaluated. The Rs value of an individual superconducting thin film can be determined without any assistance of other superconducting films or calibrators. This measurement provides a convenient and absolute approach for Rs-measurement of high Tc superconducting thin films. Also the error in the Rs-measurement with the method was discussed.

This paper uses the technical of the VPD (Virtual Product Design) with the parallel coordination design, and the problem with the tradition design like in some link has been solved. It is possibly interrupt or brings disaster to the insufficiency which directly the entire design will carry on normally, and it proposed that the hypothesized product development design (VPD) the architecture key technologies, through the hypothesized product development design cycle analysis, confirms the VPD technology sophistication fully.