1.5 ?m phase-shifted DFB lasers for single-mode operation

Fabrication and single-mode laser oscillation were demonstrated for modified DFB lasers where the phase of the corrugations was shifted at the centre by a quarter guided-wavelength and which, in principle, provided a resonance at the Bragg wavelength and stable single-mode oscillation. Phase-shifted corrugations were fabricated using electron-beam lithography.     

The role of interferon-alpha in the treatment of multiple myeloma

Interferon-alpha (IFN-alpha) is an active therapeutic agent in multiple myeloma. IFN-alpha alone may induce complete or partial responses in approximately 20% of previously untreated patients. However, it remains less effective than conventional chemotherapy. Recently, it proved to be beneficial in some but not all studies, in combination with conventional chemotherapy, to improve the overall response rate and prolong the plateau phase in patients in remission. The Hanshin Hematological Neoplasia Study Group developed a regimen consisting of DMVM (dexamethasone, MCNU, VCR, melphalan) with IFN-alpha. This regimen yields an 69% response rate, including 26% complete remissions defined by disappearance of M-protein and morphological normalization of the bone marrow. The most effective strategy of administration has yet to be established.     

A novel GaInNAs-GaAs quantum-well structure for long-wavelengthsemiconductor lasers

We propose a novel quantum-well (QW) structure for GaInNAs-GaAs lasers that can emit 1.3 μm or longer wavelength light. The idea is insertion of lattice-matched GaInNAs intermediate layers between well and barrier, which is effective for elongating the emission wavelength and reducing well thickness. It is shown that 1.3-μm emission is achievable by using the proposed GaInNAs-GaAs QW with a well thickness thinner than that of conventional rectangular GaInNAs QWs. This structure will relax the design limitation of strained GaInNAs layers     

C-Mode Scan and Resolution Improvement Techniques for Ultrasonic Diagnosis

This paper presents a new method for obtaining plane images perpendicular to the axis of the transducer and discusses some resolution improvement techniques utilizing a computer. The method, called C-mode scan, is carried out by successive application of a conventional B-mode scan, and supplies more information such as the outline, size, and extent of a lesion such as a breast tumor. To improve the resolution of a transducer, a deconvolution technique together with non-linear filtering are employed from a spectral point of view. Several clinical images produced by C-mode and the computer improvement of resolution are demonstrated.     

Receptor-mediated and receptor-independent activation of G-proteins in rat brain membranes

High-affinity GTPase activity intrinsic to G-proteins, which serves as an index of G-protein activation elicited through agonist-stimulated receptors as well as by receptor-independent direct G-protein activators like mastoparan, was measured in rat brain membranes. Receptor-mediated high-affinity GTPase activity was detectable preferentially for the Gi subfamily associated with adenylyl cyclase inhibition mediated by group II metabotropic glutamate, pirenzepine-insensitive muscarinic acetylcholine, GABA(B), adenosine A1, dopamine D2-like (striatum), and serotonin 5-HT1A (hippocampus) receptors. The pharmacological characteristics of such receptor-mediated high-affinity GTPase activities were presented. Mastoparan, a tetradecapeptide from wasp venom which has been shown to directly activate Gi and Go, inhibited low-affinity GTP hydrolyzing activity, probably due to its activating effect on nucleoside diphosphokinase (NDPK). When NDPK activity was inhibited completely by UDP, mastoparan stimulated high-affinity GTPase activity in a concentration-dependent manner. There are many compounds other than mastoparan with apparently diverse structural properties which have been shown to directly activate G-proteins. The relevance and possible participation of receptor-independent mode of G-protein activation for some neuropeptides were discussed.     

Comments on "Determination of matrix transfer function in the form of matrix fraction from input-output observations"

-Furuta and Paquet have proposed an algorithm for determining coefficients of an input-output relation from input-output observations. The purpose of this note is to point out that these coefficients can be obtaiined by a simpler algorithm which requires less computation and that there are other algorithms for minimal realization from these coefficients.     

A case report of incomplete endocardial cushion defect with mitral stenosis in an elderly patient

The following paper describes a mitral valve replacement (SJM 27 mm), the patch closure (EPTFE) of an ostium primum atrial septal defect and tricuspid annuloplasty (De Vega's method) in a 64-year-old female patient with an incomplete endocardial cushion defect and mitral stenosis. Surgery revealed thickened, mitral valve leaflets and the presence of a cleft, findings similar to those observed in case of rheumatic degeneration. Investigation of patient hemodynamics confirmed a diagnosis of Lutembacher syndrome and a lower with left ventricle volume. After surgery, the volume of left ventricle increased and the patients clinical course was uneventful.     

Early construction and operation of the highly contaminated water treatment system in Fukushima Daiichi Nuclear Power Station (III) – a unique simulation code to evaluate time-dependent Cs adsorption/desorption behavior in column system

A simulation code was developed to evaluate the performance of the cesium adsorption instrument operating in Fukushima Daiichi Nuclear Power Station. Since contaminated water contains seawater whose salinity is not constant, a new model was introduced to the conventional zeolite column simulation code to deal with the variable salinity of the seawater. Another feature of the cesium adsorption instrument is that it consists of several columns arranged in both series and parallel. The spent columns are replaced in a unique manner using a merry-go-round system. The code is designed by taking those factors into account. Consequently, it enables the evaluation of the performance characteristics of the cesium adsorption instrument, such as the time history of the decontamination factor, the cesium adsorption amount in each column, and the axial distribution of the adsorbed cesium in the spent columns. The simulation is conducted for different operation patterns and its results are given to Tokyo Electric Power Company (TEPCO) to support the optimization of the operation schedule. The code is also used to investigate the cause of some events that actually occurred in the operation of the cesium adsorption instrument.