RESUMO
We have measured the 3dâ2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst) eV and 6463.7±0.3(stat)±0.1(syst) eV, and widths to be 2.5±1.0(stat)±0.4(syst) eV and 1.0±0.6(stat)±0.3(stat) eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.
RESUMO
The usefulness of a covered self-expandable metallic stent for benign esophageal stricture and perforation was well established. In case of benign disease, early stent removal was recommended within 6-8 weeks after placement. A case with severe esophageal stricture caused by incomplete stent removal 7 years after stent placement for spontaneous esophageal rupture was reported. Residual stent fragments could be removed by step-by-step multimodal endoscopic treatment, producing satisfactory luminal diameter of the esophagus. In particular, stent trimming with argon plasma coagulation was safe and effective strategy. The endoscopic stent removal is minimally invasive and should be attempted before surgical intervention; however, it is most important to ensure early stent removal before tissue ingrowth or overgrowth can develop.