Persistent biliary leaks, whether iatrogenic or secondary to malignancy, often present a difficult management problem. Recent reports have suggested a role for covered metallic stents in this context. We describe the successful use of a covered stent to seal a persistent biliary leak following radiofrequency ablation of colorectal liver metastases.

An oil-immersed power transformer in a hydro power station has the potential for fire, explosion and oil leakage that can cause serious damage to equipment and the environment, because they are generally located in underground vaults or adjacent to watersheds. Many power stations have aged oilimmersed power transformers which have higher potential risks of failure and transformer owners must pay careful attention to the aged transformer. A SF 6 gas insulated and cooled transformer (GIT) is nonexplosive, non-flammable and oil-free. This technology can provide an effective solution to eliminate the risks of fire, explosions, water pollution due to oil leakage.

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The authors report on the design, characterization, and performance of silicon-rich SiGe waveguide photodetectors grown directly on silicon without virtual buffer relaxation layers. The type-II band offsets of the SiGe system is used to engineer a "W-structure" for absorption at 1.3 m. Multimode waveguide devices are found to have a responsivity of 13.2 mA/ W and a specific detectivity of 1.8ϫ 10 8 cm Hz 1/2 W −1 at 1.3 m. Variation in the responsivity versus length of single-mode waveguide devices was used to characterize the material, yielding an optical absorption coefficient of 11.21 cm −1 for a single active region that is 25 Å thick. The 500 m long single-mode devices exhibit a 3 dB bandwidth of 1.54 GHz.

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