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Relative contributions of the solutal natural and Marangoni (thermal and solutal) convective flows to the melting process of a GaSb-InSb-GaSb system under normal and reduced gravity conditions were investigated. Numerical simulation results show that thermal Marangoni convection enhances the melting near the free surface under both normal and zero gravity conditions. The contribution of the solutal Marangoni convection to the flow field is less than that of the thermal Marangoni convection under normal gravity. This is due to the fact the heavier component sinks to the lower part of the melt, and the concentration gradient along the free surface becomes very gentle. Consequently, the intensity of the solutal Marangoni convection is very small in spite of the associated Marangoni number being large. On the other hand, the interface shape is greatly affected by the presence of solutal Marangoni convection under the reduced gravity field although the flow velocity of the solutal Marangoni convection is very small. more...

To report a case of lattice corneal dystrophy (LCD) with Asn544Ser (N544S) mutation of the transforming growth factor beta-induced (TGFBI) gene.A 68-year-old male patient with late-onset, sporadic LCD without corneal erosion. Amyloid deposits showing dot and lattice lines were seen in the mid to deep stroma. After obtaining appropriate informed consent, genomic DNA was amplified by polymerase chain reaction (PCR) and directly sequenced.A heterozygous single base pair transition (AAT --AGT), resulting in substitution of serine for asparagine at codon 544 of the TGFBI gene, was detected.The case was classified as atypical type IV because of the late onset, lack of corneal erosion, and amyloid deposits in the mid to deep stroma. more...

Critical currents and flux pinning were examined in (103)- and (001)-oriented YBa2Cu3O7−x thin films at liquid nitrogen temperature (77.3K) under magnetic fields applied perpendicular to the film surface. Measurements were made in the [010] and [301] transport current directions for the (103)-oriented films. The field-dependent terms of the pinning force density F p were found to be described by the single Kramer scaling law irrespective of crystallographic orientation and transport current direction: F p/F p max ∝ b 1/2(1 − b)2, where F p max is the maximum pinning force density and b is the reduced field defined as b ≡ B/B i (B i: irreversibility field). more...

YBa2Cu3O7+y samples, slowly cooled after annealing, are orthorhombic and exhibit a complete transition at 90 K. On the contrary, rapidly quenched samples are tetragonal and their T c's are 20 K lower than those of the slowly cooled ones. It is found from thermogravimetric analysis that the amount of oxygen deficiency in the tetragonal samples is greater than the orthorhombic ones. This fact indicates that the structural difference is attributed to both the disordering of oxygen vacancies and the difference in oxygen vacancy amount. In addition, YSr2Cu3O7+y samples are tetragonal and exhibit complete transition at 81 K. more...

Microwave-induced high dc voltage of a few millivolts across the unbiased BaPb0.7Bi0.3O3 Josephson tunnel junction array is observed. A nearly rectangular hysteresis loop due to the voltage generation appears in current-voltage curve. The loop depends on load resistance, rf power and length and width of the sample. The induced voltage polarity can be easily switched by an external pulse current input signal of only 50 A/cm2. This voltage switching can probably be exploited in the Josephson junction array as a future element. more...

The microwave-induced, quantized high dc voltage of about 2 mV across the unbiased BaPb0.7Bi0.3O3 Josephson tunnel junction array is observed. The nearly rectangular hysteresis loop due to the voltage generation appears in the current-voltage curve. The induced voltage polarity can easily be switched by an external pulse current input signal of only 50 A/cm2. This voltage switching can probably be exploited in the Josephson junction array as a future logic element. more...