Current-induced synchronized switching of magnetization

We investigate current-induced magnetization switching for a multilayer structure that allows a reduced switching current while maintaining high thermal stability of the magnetization. The structure consists of a perpendicular polarizer, a perpendicular free-layer, and an additional free-layer having in-plane magnetization. When the current runs perpendicular to the structure, the in-plane free-layer undergoes a precession and supplies an internal rf field to the perpendicular free-layer, resulting in a reduced switching current for one current polarity. For the other polarity, the in-plane free-layer almost saturates perpendicular to the plane and acts as another perpendicular polarizer, which also reduces the switching current.Comment: 18 pages, 4 figure

Magnetization dynamics induced by in-plane currents in ultrathin magnetic nanostructures

Ultrathin magnetic systems have properties qualitatively different from their thicker counterparts, implying that different physics governs their properties. We demonstrate that various such properties can be explained naturally by the Rashba spin-orbit coupling in ultrathin magnetic systems. This work will be valuable for the development of next generation spintronic devices based on ultrathin magnetic systems.Comment: 4+ pages, 3 figure

Fabrication of AlGaN/GaN Fin-Type HEMT Using a Novel T-Gate Process for Improved Radio-Frequency Performance

To increase the radio-frequency (RF) performance of AlGaN/GaN-based fin-type high electron mobility transistors (HEMTs), a novel T-gate process was developed and applied to fabricate a device with high RF performance. In a single lithography process, the applied T-gate process shows a technique for forming a T-gate using the reactivity difference of several photoresists. The fabricated device has a steep fin width (W-fin) of 130 nm, a fin height (H-fin) of 250 nm, and a gate length (L-G) of 190 nm. The device exhibits a low leakage current (I-off) of 6.6 x 10(-10) A/mm and a high I-on/I-off current ratio of 4.7 x 10(8). Moreover, the fabricated device achieved a high cut-off frequency (f(T)) of 9.7 GHz and a very high maximum oscillation frequency (f(max)) of 27.8 GHz. The f(max) value of the proposed device is 138% higher than that of GaN-based fin-type HEMTs without T-gate.1

Malignant ocular melanoma in a dog

A mongrel male dog of three years old was referred to the Seoul National University Veterinary Teaching Hospital following a one month history of glaucoma. On ophthalmic examination, hyphema, glaucoma, uveitis, iridal mass, and loss of vision were noted in the right eye. Ultrasonography and computed tomography revealed a mass with involvement of the entire uvea. Radiographic evaluation did not reveal any evidence of distant metastasis. The right eye was surgically removed because of the high likelihood of neoplasia. A histologic diagnosis of malignant uveal melanoma was made

Recurrent Streptococcus Pneumoniae Meningoencephalitis in a Patient With a Transethmoidal eningoencephalocele

We report a case of recurrent Streptococcus Pneumoniae meningoencephalitis with a transethmoidal meningoencephalocele (TEME) but without cerebrospinal fluid (CSF) leakage

Intra-host competition and interactions between Soybean mosaic virus (SMV) strains in mixed-infected soybean

Abstract Over the past two decades, the dominant Soybean mosaic virus (SMV) strain in South Korea has changed from G5 to G7H. To examine the dominance of G7H, intra-host competition between G7H and G5 was evaluated in soybean plants infected with a mixture of SMV strains. The distribution patterns of the two SMV strains in soybean plants inoculated with G7H, G5 and G7H/G5 were investigated at designated time points by RT-PCR/RFLP analysis, which enables the specific differentiation of low concentrations of SMV strains and the detection of mixed infection at any given time. When leaves of 'Kwangankong' and 'Tawonkong' were infected with both strains, the upper leaves had only the G7H strain in simultaneous infections. In sequential inoculations, the leaves exhibited mosaic symptoms caused by G7H, and the G5 strain was not detected in plants pre-inoculated with the G7H strain before inoculation with the G5 strain. In the reverse treatment, both G5 and G7H were present at every vegetative stage. In addition, interactions between the virulence and dominance of G7H, G5, and G1, a less virulent strain, were investigated. Three landrace soybeans were co-inoculated with G7H/G5, G7H/G1, G5/G1, and G7H/G5/G1 sets. There was no significant difference between virulence and dominance. These results demonstrate the dominance of G7H in mixed infections and could explain the prevalence of G7H in South Korea