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The optical propagation loss of rib waveguides fabricated on magnetic garnet films increased upon annealing in H2 ambient during wafer direct bonding. The heat treatment in wafer direct bonding between InP and Gd3Ga5O12 was investigated with the aim of circumventing the loss increase. The bonding was achieved by heat treatment in H2 ambient at temperatures of ≦330° C or in N2 ambient.

Rib waveguides, which are made of magnetic garnet films of composition (GdBi)3Fe5O12 and are fabricated by Ar sputter etching, have large optical propagation loss when Ti is used as the etch mask. The loss increase is alleviated by using a SiO2 mask. X-ray photoelectron spectroscopy analysis reveals that Fe chemical shift due to Ar+ ion bombardment causes increase in the optical absorption loss, and hence the propagation loss.

Rib waveguides, which are made of magnetic garnet films of composition (LuNdBi)3(FeAl)5O12 (LNB), fabricated by Ar sputter etching have large propagation loss in comparison with LNB slab waveguides. X-ray photoelectron spectroscopy (XPS) is used to investigate chemical states of constituent elements existing in the surface layer where a Ti mask has been deposited during the etching process. The analysis shows that Fe chemical shift due to Ar+ ion bombardment can cause increase in the optical absorption loss, and hence the propagation loss. It is effective for suppressing the loss increase to employ a SiO2 mask deposited onto LNB film instead of a Ti mask.

This paper reports the results of crystal growth of InP on a Gd3Ga5O12 (GGG) substrate. Effectiveness of the In-P/GaInAsP superlattice is shown. Substrate orientations of (100) and (111) are compared. By using the GGG(100) substrate and introducing the superlattice, the best result was obtained for growing an InP layer. From X-ray diffraction analysis, it was found that the grown InP layer was preferentially (111) oriented along the film normal. SEM and RHEED observation revealed that the grown layer was composed of polycrystalline grains with random orientation in the film plane.

Ferrite is a non-reciprocal material which is used in non-reciprocal devices such as isolators or circulators for the microwave and optical bands. Waveguides containing ferrite, are usually analyzed by 2-dimensional approximations but not by 3-dimensional analysis. This paper utilizes a mode-matching method to analyze ferrite image lines, and the analysis is compared with experiment. First, the mode-matching method is applied to the mode analysis of a ferrite slab and we find its dispersion and field distribution. These modes are then used to analyze the image waveguide, especially its field patterns, which are quite different from those for the dielectric case; finally its validity is confirmed by experiment.

Twelve patients with mechanical infertility in the in vitro fertilization program were studied. Seven of them received halothane anaesthesia and the other five received neuroleptanaesthesia. Higher plasma prolactin levels and lower plasma progesterone levels were observed in the neuroleptanaesthesia group than in the halothane group during and after transvaginal ultrasound-guided oocyte pick-up. Plasma adrenocorticotropic hormone and cortisol levels of the patients suggested that surgical stress was minimal in both groups. It is likely that droperidol and fentanyl, both used in neuroleptanaesthesia, were responsible for the hyperprolactinaemia which was followed by inhibition of progesterone production. These agents, therefore, are not recommended as anaesthetic agents for transvaginal ultrasound-guided oocyte pick-up.

When ferrites are used for electromagnetic wave absorbers in the VHF and UHF bands we note their excellent properties such as their wider dynamic frequency bandwidth and their thinner thickness than that of lossy dielectric absorbers, which are due to their magnetic losses. However, there exists an upper frequency limit beyond which the frequency bandwidth of ferrite absorbers becomes narrower than that of lossy dielectric absorbers. In this paper we added ferrites to carbon-rubbers and examined their characteristics as electromagnetic wave absorbers. We found through experiments that the relative bandwidth is widened more than twice by adding ferrites of only relative weight ratio 0.2 to rubber when the relative weight ratio of carbon to rubber is 1.1. Although we made measurements in the frequency range of 5 to 6 GHz, we expect the same effectiveness at higher frequencies.

Birefringent material in a thin film dielectric waveguide is used to realize phase matching of the waves with different polarizations. However, this method cannot be used exclusively due to lattice mismatch as happens in a mode conversion type isolator. This paper proposes an artificial anisotropic waveguide realizing phase matching with isotropic dielectric materials only. the structure is a slab waveguide loaded with dielectric strips parallel to the wave propagation direction. This structure can equalize the phase velocities of the Ex and Ey modes. A numerical analysis based on the mode matching technique is used to obtain the phase match condition. the effect of an artificial anisotropy is confirmed in a waveguide fabricated in experiments. A waveguide is realized in which difference of the propagation constants of the Ex and Ey modes is extremely small. It is believed possible that a thin film optical isolator can be reproduced with this waveguide.

The characteristics of an optical nonreciprocal phase shifter, with which optical circulators can be constructed, are investigated. We have measured the nonreciprocal phase shift of an appropriately magnetized yttrium iron garnet (YIG) thin film and thus confirmed experimentally that an AIR/YIG/GGG structure can function as an optical nonreciprocal phase shifter.

To obtain a mode converting optical isolator it is necessary to achieve phase matching of the TE and TM modes propagating through the magnetic film, such as a rare-earth garnet, etc. One of the methods of phase matching employs the birefringence induced by a lattice parameter mismatch between film and substrate. This paper presents measurement of the birefringence in YIC and Bi:YIG films grown on a GGG substrate using liquid phase epitaxy. Moreover, birefringence evaluated from the optoelastic effect and the stress calculated using a bimetal model agree well with the measured values. From these results, the birefringence induced in YIG and Bi:YIG films can be obtained theoretically. It is established that a phase-matched magnetic waveguide can be obtained using Bi:YIG thin film. Further, by using such films nonreciprocal mode convertors and isolators can be realized.

Although a number of components for millimeter-wave integrated circuits based on an open dielectric waveguide have been proposed, little has been reported on nonreciprocal devices and no significant results have been obtained. In this paper we discuss experimental verification of nonreciprocal propagation phenomena in an open ferrite waveguide and their application to open nonreciprocal devices. Based on the results, we propose a circulator of directional coupler type which makes use of nonreciprocal propagation phenomena in an open ferrite waveguide. We also propose a pillbox resonator type circulator and a junction type circulator using the nonreciprocal resonance of an open cylindrical ferrite. Circulators of the directional coupler type and the pillbox type do not need any conductor in principle. The radiation loss can be reduced without significant increase of the conductor loss if a conductor shield is used in the E-plane of the junction circulator. A junction circulator with practical characteristics is developed for millimeter-wave integrated circuits.

Previously, one of the authors proposed a ferrite strip as a non reciprocal waveguide for millimeter and optical waves. It has many features, e.g., it does not require metal conductors and optical anisotropic material (NbO3), and it generates large field displacement for small anisotropy. This type of waveguide is analyzed by a generalized transmission equation and variational method. These methods, however, are time-consuming and cumbersome. This paper proposes a simple analysis method using effective permittivity. The field distribution for weakly guiding waves and the radiation characteristics are discussed in detail. It is clear that the occurrence of large field displacement is attributable to weakly guiding waves. The cut-off condition for the fundamental wave, the condition of edge guide wave generation, the radiation loss and the asymptotic value of the field displacement, are clarified.

We compared adrenocorticotropin-releasing activities of several interleukins in a homologous or heterologous in vivo system. Intravenous injection of rat interleukin-1 α significantly increased plasma adrenocorticotropin in conscious, freely-moving rats 30 min after the injection, and the effect was 10 times greater than that of human interleukin-1 α. Rat interleukin-2 affected plasma adrenocorticotropin in a much slower manner and increased its levels significantly 120 min after the injection. Human interleukin-2 had no effect on plasma adrenocorticotropin. Thus, species difference in the experimental system should be considered to assess the physiological significance of cytokines in the neuroendocrine system.

The frequency characteristics for the power dividers with ferrite toroids, which are extensively used in CATV and/or MATV systems, are analyzed. The analytical optimum design method for the weakly-coupled power divider by the simplified model and the numerical optimum design method for the tightly-coupled power divider by the exact model are proposed, and the designed power dividers with ferrite toroids by the proposed methods have much improved frequency characteristics compared with the original power dividers. Thus, the useful bandwiths of all the power dividers have been extended from 5 to 500 MHz. Practical measurements show very good agreements with theoretical results, and, hence, the validity of the analyses and design methods for the power dividers with ferrite toroids are confirmed. Furthermore, the relations between the optimum circuit and ferrite constants have been clarified in reference to L0(i)Kfm.

Therapeutic applications of hypothalamic hypophysiotropic hormones were discussed. Pulsatile administration of gonadotropin-releasing hormone (Gn RH) is effective to maintain menstrual cycles and ovulation in female patients with hypothalamic gonadal dysfunction and testicular function in male patients. On the other hand, continuous administration of Gn-RH or its analog is able to suppress gonadal function and thereby gonadal hormonedependent activities effectively. Application of this medical gonadectomy includes treatments for excessive menstrual bleeding, endometriosis, prostatic cancer and benign prostatic hypertrophy. Thyrotropin-releasing hormone has been applied in patients with spinocerebellar degeneration or some kinds of consciousness disturbance and somatostatin analog has benn tried to treat acromegaly. Corticotropin-releasing hormone and growth hormone-releasing hormone have also therapeutic potentials. We believe that many-sided research trials, which include development of new potent analogs, new effective drug delivery systems and further elucidation of physiology and pathophysiology about the functions of the hypothalamic hormones, are inevitable to materialize therapeutic potentials of these hormones.

Ferrite, a ferromagnetic material in the form of sintered ferrite and rubber ferrite, is used for electromagnetic-wave absorbers. However, there is a certain limit to reducing the thickness of the electromagnetic wave absorber using ferrite. For obtaining thin rubber-ferrite electromagnetic-wave absorbers, carbon is added to them and their electromagnetic-wave absorbing characteristics are examined. The results show that the thickness can be reduced to about 30 percent by adding the order of 1 to 10 percent (volume ratio) of carbon to ferrite. The reduction of the thickness of the absorber also reduces its weight. The mixing of carbon is highly effective in reducing the weight of the absorber, since the specific gravity of carbon is smaller than ferrite. This paper presents the electromagnetic-wave absorption characteristics of carbon-added rubber ferrite.

This paper describes the performance characteristics of a waveguide-type optical attenuator effectual not only for Ey but Ex modes. Attenuation of more than 150 dB/mm for both modes is experimentally demonstrated.

Proposing a canonical representation, valid for analysis and synthesis, of circulator, the paper also attempts to prove the circulator's figure of merit to be invariant under an arbitrary lossless reciprocal and cyclic-symetry imbedding.

A case of juvenile angina pectoris probably due to congenital syphilis was reported. Both coronary ostial narrowing could be only presumed in usual physical and laboratory examination. And then aortitis and both coronary ostial stenosis demonstrated in vivo by aortography and selective coronary arteriography. The progress of this case has been observed at present with internal treatments, but surgical repair will be necessary in the near future.

The gap between ferrite tiles degrades the characteristics of ferrite electromagnetic wave absorbers at low frequency. In order to circumvent this, the authors investigated the effect of inserting ferrite powder or rubber ferrite into the gap. Both numerical calculations and experimental studies show that, when the gap is filled with the ferrite powder or the rubber ferrite, the degradation of reflectivity due to the presence of the gap can be reduced compared to the case of the air gap. It is shown that the higher the permeability of the ferrite powder, the less the degradation of the reflectivity becomes. Also, it becomes clear that the degradation of reflectivity due to the air gap in a ferrite grid absorber is less compared to the conventional ferrite tile absorber.

Experirnents on a new edge-guided mode isolator are reported. In this isolator, one edge of a wide strip is shorted to the ground, and no lossy electrical materials are used. Large isolation and small insertion losses were obtained.