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Radiofrequency ablation (RFA) has become an accepted alternative for treating intrathoracic malignancies; however, the incidence and characteristics of peri‐ and postprocedural complications are not well described. The purpose of the study was to assess the safety and technical feasibility of percutaneous RFA in unresectable intrathoracic malignancies.Percutaneous RFA was performed in patients with intrathoracic malignancies between June 2001 and December 2004. In total, 366 tumors were treated in 137 patients in 211 sessions. All patients were nonsurgical candidates or had refused surgery. Three hundred and thirty‐six lesions were subjected to RFA for the treatment of metastases and 30 lesions for primary lung carcinoma.Although no procedural mortality occurred, 2 patients died during the course of the study because of intractable pneumothorax and massive hemoptysis (0.9%). The overall major complication rate was 17.1% (pneumothoraces requiring tube drainage in 25, pleuritis in 6, pleural effusion requiring tube drainage in 4, lung abscess in 1, and intrapulmonary hemorrhage with hemothorax in 1). Minor complications included pneumothoraces not requiring tube drainage in 108 sessions, pleural effusion without drainage in 34, hemosputum in 9, nausea and/or vomiting in 3, subcutaneous emphysema in 3, cough in 2, skin burn in 2, atelectasis in 1, and subileus in 1. High fever and/or chest pain were seen in 33.8% and 39.3% of patients, respectively.With over 200 procedures, RFA appears to be a safe and minimally invasive option with negligible mortality and little morbidity in selected patients with unresectable intrathoracic malignancies. Cancer 2007. © 2007 American Cancer Society. [ABSTRACT FROM AUTHOR]

The three-dimensional imaging of threading dislocations in GaN films was demonstrated using two-photon excitation photoluminescence. The threading dislocations were shown as dark lines. The spatial resolutions near the surface were about 0.32 and 3.2 µm for the in-plane and depth directions, respectively. The threading dislocations with a density less than 108 cm−2 were resolved, although the aberration induced by the refractive index mismatch was observed. The decrease in threading dislocation density was clearly observed by increasing the GaN film thickness. This can be considered a novel method for characterizing threading dislocations in GaN films without any destructive preparations. [ABSTRACT FROM AUTHOR]

Halide vapor phase epitaxy of thick GaN films was demonstrated on ScAlMgO4 (SCAM) substrates, and their self-separation was achieved. The 320-µm-thick GaN film was self-separated from the SCAM substrate during the cooling process after the growth. This separation phenomenon occurred because of both the c-plane cleavability of SCAM and the difference in the thermal-expansion coefficients between GaN and SCAM. The dark-spot densities for the GaN films on the SCAM substrates were approximately 30% lower than those on sapphire substrates. These results indicate that SCAM substrates are promising for fabricating a high-quality freestanding GaN wafer at a low cost. [ABSTRACT FROM AUTHOR]

We fabricated high-output-power 255 and 280 nm light-emitting diodes (LEDs) using direct bonding. The LED chips were bonded to sapphire lenses at room temperature using either atomic diffusion bonding or surface-activated bonding. The LEDs with lenses had a higher light extraction efficiency than conventionally structured LEDs. As a result, at a forward current of 350 mA, the output power of the 255 nm LED increased by a factor of 2.8, reaching 73.6 mW, while that of the 280 nm LED increased by a factor of 2.3, reaching 153 mW. [ABSTRACT FROM AUTHOR]

We fabricated three types of high luminous efficacy white light emitting diodes (LEDs). The first was a white LED with a high luminous efficacy (eL) of 249 lm W[?]1 and a high luminous flux (phv) of 14.4 lm at a forward-bias current of 20 mA. This eL was approximately triple that of a tri-phosphor fluorescent lamp (90 lm W[?]1). The blue LED used as the excitation source in this white LED had a high output power (phe) of 47.1 mW and a high external quantum efficiency (eex) of 84.3%. The second was a high-power white LED, fabricated from the above high-power blue LED, and had a high phe of 756 mW at 350 mA. phv and eL of the high-power white LED were 203 lm and 183 lm W[?]1 at 350 mA, respectively. The third was a high-power white LED fabricated from four high-power blue LED dies. phv and eL of the high-power white LED were 1913 lm and 135 lm W[?]1 at 1 A, respectively. The white LED had a higher flux than a 20 W-class fluorescent lamp and 1.5 times the luminous efficacy of a tri-phosphor fluorescent lamp (90 lm W[?]1). [ABSTRACT FROM AUTHOR]