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Summary: A new type of silicone rubber (SR)‐based gamma radiation shielding and thermal regulation composite was developed with paraffin (Pn) @lead tungstate (PWO) phase‐change microcapsules as functional fillers. These SR/Pn@PWO composites have a PWO component that not only exhibits excellent photon attenuation but also can provide a barrier to the molten phase‐change material core. The thermal and mechanical properties of the composites were characterized by differential scanning calorimetry, thermal regulation experiment and mechanical tests. Thermal analysis indicated that the SR/Pn@PWO composites not only reveal reliable energy storage performance which can reach to 52.72 J g−1 enthalpy values but also exhibit good thermal durability. In addition, SR/Pn@PWO composites have enhanced mechanical properties and excellent thermoregulation performance. And the more microcapsules content, the more significant enhancement effect is. A high‐purity germanium gamma spectrometer to measure the attenuation coefficient of the composites for gamma radiation showed that the SR/Pn@PWO composites have good γ‐ray‐shielding property, which increased with the increase of the microcapsules content. [ABSTRACT FROM AUTHOR]

Background: Magnetic navigation system (MNS) assisted percutaneous coronary intervention (MPCI) has been demonstrated an advantage over conventional PCI (CPCI) in complex lesions and tortuous vessels. However, the benefits of MNS in clinical unstable and vulnerable lesions were little studied. The aim of this study is to evaluate the feasibility and benefits of MPCI versus CPCI in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS). Methods: Thirty-seven consecutive patients with NSTE-ACS undergoing MPCI were compared with 37 matched CPCI patients selected from the same concurrent database. Time to cross lesion, fluoroscopy time, and contrast usage to cross lesion were used as primary end-points. Results: Of the 37 culprit lesions in MPCI, 36 were crossed successfully giving a success rate of 97.3%. The procedure and the fluoroscopy time to cross the lesion were similar between the magnetic and conventional PCI groups (82.0 ± 67.9 seconds vs. 85.8 ± 59.2 seconds, P = 0.692, and 62.6 ± 57.6 seconds vs. 65.4 ± 49.5 seconds, P = 0.738, respectively). In Type A/B1 lesions, there seemed no difference in contrast use (2.7 ± 0.7 mL vs. 3.3 ± 0.9 mL, P = 0.284). But as lesion complexity increased from type B2 to C, significantly less contrast was needed in type B2 (5.1 ± 2.6 mL vs. 7.9 ± 4.0 mL, P = 0.019) and type C (9.8 ± 5.7 mL vs. 14.7 ± 7.4 mL, P = 0.030). No major adverse cardiac events were observed in either the MPCI or CPCI group. Conclusions: MNS assisted technique appears to be feasible and effective in NSTE-ACS patients with more complex lesions; however, it probably offers little benefit in simple lesions like ACC/AHA type A/B1. (J Interven Cardiol 2011;24:549-554) [ABSTRACT FROM AUTHOR]