InGaN/GaN superlattice underlayer for fabricating of red nanocolumnµ-LEDs with (10-11) plane InGaN/AlGaN MQWs.

In this study, the growth behavior of Indium gallium nitride (InGaN)-based nanocolumn arrays was investigated, and red emission nanocolumn micro-light emitting diodes (µ-LEDs) were fabricated. The internal structure of the InGaN/GaN superlattice (SL) layer under the multiple-quantum-well (MQW) active layers was evaluated using scanning transmission electron microscopy (STEM) analysis. It was revealed that the InGaN crystal plane at the top of the nanocolumn changed from the c-plane, (1-102) plane, to the (10-11) plane as the number of SL pairs increased. A semipolar (10-11) plane was completely formed on top of the nanocolumn by growing InGaN/GaN SLs over 15-20 pairs, where the InGaN/GaN SL layers were uniformly piled up, maintaining the (10-11) plane. Therefore, when InGaN/AlGaN MQWs were grown on the (10-11) plane InGaN/GaN SL layer, the growth of the (10-11) plane semipolar InGaN active layers was observed in the high-angle annular dark field (HAADF)-STEM image. Moreover, the acute nanocolumn top of the (10-11) plane of the InGaN/GaN SL underlayer did not contribute to the formation of the c-plane InGaN core region. Red nanocolumnµ-LEDs with anφ12µm emission window were fabricated using the (10-11) plane MQWs to obtain the external quantum efficiency of 1.01% at 51 A cm-2. The process of nanocolumnµ-LEDs suitable for the smaller emission windows was provided, where the flat p-GaN contact layer contributed to forming a fine emission window ofφ5µm.

Conceptual design of the Hybrid Ring with superconducting linac.

The Hybrid Ring with a superconducting-linac injector as a highly flexible synchrotron radiation source to enable new experimental techniques and enhance many existing ones is proposed. It is designed to be operated with the coexistence of the storage (SR) bunches characterized by the performance of the storage ring, and the single-pass (SP) bunches characterized by the performance of the superconducting linac. Unique experiments can be performed by simultaneous use of the SR and SP beams, in addition to research with various experimental techniques utilizing the versatile SR beam and research in the field of ultrafast dynamics utilizing the ultrashort pulse of the SP beam. The extendability of the Hybrid Ring will allow it to be developed into a synchrotron radiation complex.

Diffuse large B-cell lymphoma presenting with hypercalcemia and multiple osteolysis.

Osteolysis and hypercalcemia are observed in 5-15%, and 10%, respectively, of malignant lymphoma patients during their clinical course. However, both osteolysis and hypercalcemia are uncommon at onset of the disease. We encountered a 24-year-old male non-Hodgkin's lymphoma patient who had multiple osteolytic lesion from the onset of the disease and repeated episodes of hypercalcemia during the clinical course. The patient died with refractory disease. We studied the expression of chemokines which might affect bone resorption using the reverse transcriptase-polymerase chain reaction (RT-PCR) method. Increased expressions of MIP-1alpha, MIP-1beta and RANKL, which are osteoclast-activating factors, were observed in the RNA derived from the patient's lymphoma cells. The secretion of osteoclast-activating factors such as MIP-1alpha by the tumor cells (and/or bone marrow stromal cells) might be involved in the etiology of osteolysis and hypercalcemia in some malignant lymphoma cases.