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著者人数: 227名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 東谷, 千比呂), Number of authors: 227 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Tokoku, Chihiro), Accepted: 2017-11-21, 資料番号: SA1170370000

We report the results of a new experimental setup to measure the mechanical loss of coating layers on a thin sapphire disk at cryogenic temperatures. Some of the authors previously reported that there was no temperature dependence of the mechanical loss from a multilayer tantala/silica coating on a sapphire disk, both before and after heat treatment, although some reports indicate that Ta2O5 and SiO2 layers annealed at 600 °C have loss peaks near 20 K. Since KAGRA—the Japanese gravitational-wave detector, currently under construction—will be operated at 20 K and have coated sapphire mirrors, it is very important to clarify the mechanical loss behavior of tantala/silica coatings around this temperature. We carefully investigate a tantala/silica-coated sapphire disk with the new setup, anneal the disk, and then investigate the annealed disk. We find that there is no distinct loss peak both before and after annealing under particular conditions. The mechanical loss for the unannealed disk at 20 K is about 5×10−4, as previously reported, while that for the annealed disk is approximately 6.4×10−4.

Fully-depleted 20-nm SOI complementary metal-oxide-semiconductor field effect transistors (CMOSFETs) were successfully fabricated without a raised source/drain (S/D) structure, instead using low-temperature selective tungsten CVD (SWCVD) technology that can reduce the S/D series resistance. The thickness of the residual SOI layer under the W-clad layer in the S/D region was 6 nm for an nMOSFET and 9 nm for a pMOSFET. For 0.15-/spl mu/m-gate CMOSFETs, the subthreshold swings were 70 and 75 mV/dec for the nMOSFET and pMOSFET, respectively. The effectiveness of SWCVD technology when applied to ultrathin SOI devices was confirmed by small Si consumption and good continuity between the W and SOI layers. We expect that the S/D series resistance can be reduced to less than 1 k/spl Omega/-/spl mu/m by optimizing the S/D implantation conditions.

A rapid-scanning spectrometer was developed for versatile use in atomic emission spectroscopy. The sine bar was removed and a laser rotary encoder was fitted to the grating shaft for wavelength synchronization. The pulses produced by the encoder when the grating shaft was driven back and forth in sector movements were counted to detect the grating angle and the wavelength. The wavelength accuracy and precision obtained were ±0.26 and ±0.013 nm, respectively. The maximum scanning speed was limited below 4000 nm/s by a malfunction in wavelength synchronization. The rapid-scanning spectrometer was successfully used for multielement determinations, correction of background emission, and characterization of an inductively coupled plasma.

The mechanism of the oscillatory phenomena of an underexpanded jet impinging on a flat plate is studied numerically. Pressure changes generated in the flow field near the plate propagate radially in the surrounding region of the jet. The configuration of the jet boundary is changed by them and so, the waves forming the underexpanded jet are displaced when they are reflected from the jet boundary. And then, the pressure disturbances return to the region near the plate. Unsteady flow with repetition of growth and decay of the separation bubble on the plate is also found under certain conditions.

KAGRA is the cryogenic interferometric gravitational wave telescope designed for the direct detection of gravitational waves from the astronomical sources. To achieve the best sensitivity, one of the most difficult challenges is cooling the mirrors to 20K to reduce the thermal noise. We developed four cryostats and sixteen very-low-vibration cryocooler units to accomplish our purpose. In this paper, we describe the outline of the cryogenic design and fabrication, and the results of the cryogenic performance test of the cryostats and cryocooler units.

Maldistribution of multidose blood cardioplegia (BCP) continues to be a problem causing perioperative subendocardial damage. However, it is not known whether alpha-adrenergic stimulation contributes to the maldistribution of multidose BCP. We have evaluated the effects of phenoxybenzamine (POB) on multidose BCP distribution, with a right heart bypass model in 14 dogs. Although gradual increases in coronary vascular resistance (CVR) were noted in the control group (CP-1: 0.53 +/- 0.08, CP-2: 0.57 +/- 0.07, CP-3: 0.78 +/- 0.10 mm Hg/ml/min/100 g), there was no significant rise in CVR in the POB group (CP-1: 0.36 +/- 0.03, CP-2: 0.37 +/- 0.04, CP-3: 0.42 +/- 0.04 mm Hg/ml/min/100 g). Improved delivery of BCP was observed in the POB group during CP-3 (endo/epicardial flow ratio 1.72 +/- 0.07 vs. 1.21 +/- 0.18 in the control group; p < 0.05). These data indicate that improved delivery of BCP can be obtained by alpha-adrenergic blockade, if multiple injections of BCP are used for cardiac surgery.

We propose a standard stepped sample and specify a procedure for determining the step height for height‐scale calibration of atomic force microscopy (AFM) instruments on the order of sub‐nm to nm. The stepped Si(111) surface structure was confirmed to be the most appropriate for the standard sample by a series of round‐robin measurements carried out by a group comprising AFM instrument manufacturers and user organizations. By specifying a standard measurement procedure, the mean standard deviation of the step heights is decreased by 50%. It is also confirmed that the measured Si step height is accurate to ±5%, which is consistent with the accuracy obtained for higher step standard samples. A prototype common data processing software program containing the algorithm of the specified procedure was used to allow direct comparison of the untreated measurement data from each organization.

In interferometric cryogenic gravitational wave detectors, there are plans to cool mirrors and their suspension systems (payloads) in order to reduce thermal noise, that is, one of the fundamental noise sources. Because of the large payload masses (several hundred kg in total) and their thermal isolation, a cooling time of several months is required. Our calculation shows that a high-emissivity coating (e.g. a diamond-like carbon (DLC) coating) can reduce the cooling time effectively by enhancing radiation heat transfer. Here, we have experimentally verified the effect of the DLC coating on the reduction of the cooling time., Comment: 8 pages, 9 figures, Proceedings of CEC/ICMC 2013

KAGRA is a large scale cryogenic gravitational wave telescope currently under construction in Japan. The detector is located 200 m underground in the Kamioka mine and will employ cryogenic technologies to achieve high sensitivity. The mirrors of the interferometer will be in the form of multiple pendulums and the final stages will employ cryogenic sapphire suspension system operating at 20 Kelvin. In this paper we report the ongoing activities of the cryogenic payload group involved in the design and fabrication of the cryogenic payload system for the KAGRA detector

This paper reports on the optical properties, outgassing rate, and cryogenic performance of surface finishing we have adopted for large optical baffles absorbing stray light in KAGRA, an advanced interferometer for detecting gravitational waves. The surface finishing is based on an electroless nickel-phosphorus-tungsten (NiPW) plating, applicable to large surface area up to ~ 800 mm in diameter, and achieves less than 3% total reflectance against a light beam at 1064 nm with a reasonable scattering distribution ~ 0.05/sr. The outgassing rate from the black coating meets our requirements of 3×10−7 Pa · m3 s−1 m−2. The black coating can tolerate low temperature down to 12 K, and can be installed close to cold mirrors indispensable for the future interferometers.

Background : Examination of decayed cavities by means of dental probes has been suggested to destroy decalcified enamel that still may be re-calcified, ultimately causing the development of dental caries. In the present study, we utilized the DIAGNO-DENT caries detector for examination of dental caries. Materials and methods : A total number of 193 teeth of children from eight nursery schools in the Azabu-Akasaka area of Tokyo was examined. The examination procedures consisted of visual observation, data recording, reexamination of teeth diagnosed as C0 and C1, recording of the numerical results, examining the restored teeth and data collection. Results : Dental cavities visually diagnosed as C0 or C1 showed high counting by DIAGNO-DENT examination. The degree of infection was in contrast with DIAGNO-DENT detection. Specifically, there were 12 visually diagnosed C2 that indicated DIAGNO-DENT counting under 18, suggesting that the reference counting 18–25 may not be a definitive indication of cavity preparation. Conclusion : It is possible to conclude that DIAGNO-DENT is noninvasive, easy to use and a reproductive diagnostic method. The use of DIAGNO-DENT for dental cavity detection gives more accurate diagnostic data than the traditional technique.

P-substrate buried crescent (PCB) laser diodes whose wavelength ranged from 1.2 to 1.55 mu m have been fabricated. The threshold currents as low as 10 mA have been obtained in this wavelength range experimentally. The calculated threshold currents of 13, 13, and 14 mA at 1.2, 1.3, and 1.55 mu m almost coincide with the measured values. >

We carried out feedback chirp compensation using a two-dimension spatial light modulator operating in a wavelength range from 260 to 1100 nm, which is useful for the application to ultrabroadband and high-powered optical pulses.

We fabricated a new liquid-crystal spatial light modulator for amplitude modulation of 315–1100 nm spectrum. Applied voltage and pulse width dependent transmission was characterized, which paves the way for monocycle-pulse shaping and attosecond pulse measurement.

The feasibility of synchrotron radiation lithography for the fabrication of deep-submicrometer devices has been demonstrated through the test application to the small geometry NMOS device process at all exposure levels. Excellent exposure latitude for the linewidth control was confirmed. However, improvement in overlay accuracy is still needed.

Harmonic distortion of distributed feedback laser diodes (DFB-LDs) for analog transmission systems is investigated. It is shown that, under a modulation frequency of less than 1 GHz, the harmonic distortion depends on the nonlinearity of the light output power-current (P-I) curve under the continuous wave (CW) condition, which is determined by the coupling constant kappa L, and that the distortion can be minimized at kappa L approximately 1. A 1.3 mu m wavelength InGaAsP DFB-PPIBH (p-substrate partially inverted buried heterostructure) LD and its module, with low distortion by the control of a coupling constant, have been developed. >

The low threshold current of 9 mA, the high side-mode suppression ratio of more than 45 dB, the extremely narrow spectral linewidth of 1.1 MHz, and the low chirping of 2.8 AA at -20 dB at 2 Gb/s nonreturn to zero (NRZ) modulation have been achieved in the multiple quantum well (MQW) distributed feedback (DFB) p-substrate partially inverted buried heterostructure (PPIBH) laser diode. The spectral linewidth of 1.1 MHz is the narrowest value among 300- mu m-length solitary laser diodes. These results suggest that the MQW-DFB laser diodes are a promising light source for longer distance and higher bit-rate optical communication systems and coherent optical communication systems. >

One of the most important challenges in cryogenic interferometric gravitational wave detectors is to reduce the undesirable thermal radiation coming through holes in the radiation shield, which are necessary for the laser beam to pass through. For this purpose, pipe-shaped radiation shields called duct shields are used. Here, we have manufactured duct shields for KAGRA in Japan, one of the cryogenic interferometric gravitational wave detectors, and measured the thermal radiation coming through the duct shields. The measured result was found to be consistent with the calculation result that the duct shield can reduce the thermal radiation to less than 1%. This fact confirmed that the amount of thermal radiation coming through the duct shields was smaller than KAGRA?s requirement.

An experiment to distinguish between diffusive and specular surfaces for thermal radiation in cryogenic gravitational-wave detectors Yusuke Sakakibara1,∗, Nobuhiro Kimura2, Toshikazu Suzuki2, Kazuhiro Yamamoto1, Chihiro Tokoku3, Takashi Uchiyama1, and Kazuaki Kuroda1 1Institute for Cosmic Ray Research (ICRR), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582, Japan 2High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan 3Research Center for Electron Photon Science, Tohoku University, 1-2-1 Mikamine, Taihaku-ku, Sendai, Miyagi 982-0826, Japan ∗E-mail: ysakaki@icrr.u-tokyo.ac.jp

We have been developing roll-to-roll production technologies of amorphous-silicon solar cell on plastic-film substrates. In this paper, newly developed deposition methods of (1) excitation-frequency controlled plasma-enhanced chemical vapor deposition of amorphous silicon, (2) selective reactive sputtering of metal electrode with low substrate temperature and (3) deposition of large-area uniform transparent conductive oxide are described. The solar cells were applied to 4 m-long light-weight and large-area building-integrated modules.

In development of an artificial heart, thrombus formation is still serious problem. However, there is no effective means to detect a thrombus. An optical measurement method is one of the best approaches which realize noninvasive thrombus detection. The purpose of this research is to develop the noninvasive thrombus detection method using NIR (Near Infra-Red) laser, and to apply the method to clinical use. By considering the optical characteristic of a thrombus and blood, we have developed the new thrombus detection system. By using this measurement system, the mockup experiment and the animal experiment were performed to detect a fake thrombus such as plastic beads (r=0.2 mm) and celite powder (0.1/spl times/0.02 mm) in the artificial heart circulatory system. The thrombus detection performance and safety of this method have been confirmed as the result of these experiments. After obtaining informed consent, the measurement examination was performed to the artificial heart (LVAS: Left Ventricular Assist System) use patient as the clinical application, and similar signals (LMES; Laser-detected Micro-Embolus Signals) corresponding to the animal experiment were detected. The proposed noninvasive thrombus detection method using NIR laser would be regarded as effective in the surveillance of the thrombus formation at the time of clinical artificial heart use.

Silicon-on-insulator (SOI) devices have several advantages. Small parasitic capacitances make them useful for high-speed, low-power and low-voltage LSIs. SOI devices are soft-error free, latchup free, and have a high-density layout due to complete isolation. In this paper, we report a 0.25 /spl mu/m CMOS/SIMOX 300 kG gate array LSI using fully-depleted MOSFETs fabricated on a low-dose high-quality SIMOX substrate.

Dynamic performance and leakage current characteristics of fully-depleted quarter-micron-gate CMOS/SIMOX devices are examined using a new test structure built on a 1.4-/spl mu/m-pitch gate array. High speed and low power characteristics of various loaded CMOS/SIMOX logic gates have been verified with the test structure. Furthermore, we have found that the NMOS subthreshold leakage current due to the parasitic bipolar action varies with the off-state period of input pulses during switching operation. >

A new technique is described that can effectively suppress the parasitic bipolar action in ultra-thin-film nMOSFETs/SIMOX without body contacts. Recombination centers are created in the source and drain regions by deep Ar/sup +/ implantation and these centers increase the hole current flowing from the body into the source, thereby reducing the emitter efficiency of parasitic bipolar transistors. An Ar-implanted 0.25-/spl mu/m-gate nMOSFET/SIMOX exhibited excellent improvements in characteristics: reduction in off-leakage current of over two orders of magnitude and increase in drain-to-source breakdown voltage beyond 0.6 V.

The ultra flexible lot-low management method was developed for Si wafer R&D lines. The system used comprises a scheduler and a flexible human machine interface. The scheduler is responsible for the many lots with fixed "Standard" process flows, while the "Advanced" lots with non-fixed flows are scheduled manually using the interface. This approach enhances both flexibility and efficiency of lot-flow scheduling in an R&D line consisting of the minimum amount of equipment.

KAGRA is a project to construct a cryogenic interferometric gravitational wave detector in Japan. Its mirrors and the lower parts of the suspension systems will be cooled to 20 K in order to reduce thermal noise, one of the fundamental noise sources. One of the key features of KAGRAʼs cooling system is that it will keep the mirrors cooled without introducing vibration. This paper describes the current status of the design, manufacture and testing of the KAGRA cooling system.

A 3.7-year-old girl presented with an anterior neck injury followed by progressive subcutaneous emphysema and loss of consciousness. After resuscitation, a laceration on the first tracheal cartilage was closed surgically. As she was extubated one week later, she was found to have right hemiplegia and muteness. MRI showed a T2-bright lesion on the tegmentum of the left midbrain down to the upper pons. Right vertebral angiography disclosed an intimal flap with stenosis at the C3 vertebral level presumably caused by a fracture of the right C3 transverse process later confirmed in a cervical 3D-CT scan. Her muteness lasted for 10 days, after which she began to utter some comprehensible words in a dysarthric fashion. Her neurological deficits showed improvement within 3 months of her admission. Transient mutism after brain stem infarction has not been reported previously. We discuss the anatomical bases for this unusual reversible disorder in the light of previous observations and conclude that bilateral damage to the dentatothalamocortical fibers at the decussation of the superior cerebellar peduncle may have been responsible for her transient mutism.

An effective way to reduce the power consumption of a high-speed LSI is to use two supply voltages. Most circuit parts off the critical path can then operate at a supply voltage lower than that of parts in the critical path. Rows of logic-cell blocks for example, can be assigned to circuits for either a high or low supply voltage, and this approach has been used to reduce the power consumption of a 75-MHz 0.3-/spl mu/m bulk CMOS media processor using both 3.3-V and 1.9-V supply voltage. Here we use a fully depleted CMOS/SIMOX device and 2-V/1-V supply voltages to enhance the low-power characteristics of the two-supply-voltage technique with a little area penalty.

Many studies worldwide are currently developing interferometric methods for detecting gravitational waves and one of the challenges in such methods has been to sufficiently cool the mirror in interferometric detectors in order to reduce thermal noise. Although the mirror is surrounded by a radiation shield, a hole in the shield is necessary to allow the laser beam to pass. To reduce the thermal radiation caused by the presence of the hole, we will install a duct shield with baffles. To calculate the heat input through the duct shield, we applied a ray trace model whose results were consistent with those of an experiment without baffles. As an application of our model, the heat input in the case of KAGRA (a Japanese cryogenic gravitational wave detector project) was calculated. Our analysis suggests that baffles in the duct shield can considerably reduce the heat input in KAGRA.

We analyzed the spectral components of RR interval variability under controlled respiration (15 breaths/min) in 56 patients (age range, 35-73 years) referred for coronary angiography; 14 patients had multivessel disease (group M), 21 had one-vessel disease (group S), and 21 had nonsignificant disease or normal coronary artery (group N). There were 43 healthy controls (age range, 36-71 years) (group C). The patients had no clinical evidence of heart failure, hypertension, diabetes mellitus, or acute stage of infarction and had taken no medication for 3 days. The autoregressive power spectral density of RR interval variability contains two major components, respiratory sinus arrhythmia (RSA) (0.25 Hz) and Mayer wave-like sinus arrhythmia (MWSA) (0.04-0.15 Hz), which have magnitudes that are quantitative markers of cardiac vagal activity and sympathetic activity with vagal modulation, respectively. We represented the magnitudes by the coefficient of component variance (CCV), which provided the amplitude relative to the mean RR interval. The age- and sex-adjusted mean of CCVRSA significantly decreased with advancing angiographic severity (1.64 +/- 0.09%, 1.66 +/- 0.12%, 1.22 +/- 0.13%, and 0.81 +/- 0.16% for groups C, N, S, and M, respectively) (p = 0.0001). The CCVRSA was unrelated to left ventricular function, previous myocardial infarction, or stenosis of any specific artery including the sinoatrial and atrioventricular node arteries. The CCVMWSA decreased only in group M (p = 0.0462). These results indicate that coronary artery disease is associated with vagal dominant impairment in autonomic cardiac function and that reduction in the vagal cardiac function correlates with the angiographic severity.

To investigate the diurnal variation in autonomic cardiac control, the magnitudes of the power spectral components of supine and standing heart rate variability were measured during controlled respiration (15 breaths/min). Examination was performed hourly between 0700 and 2300 h in eight male subjects whose activities and food intake were controlled for 24 h in the laboratory. The respiratory component (0.25 Hz) was greater in the morning than in the late afternoon (P less than 0.05) and decreased 30 min after food intake (P less than 0.01) in the supine position, but it was unaffected by the time of day or food intake while in the standing position. The Mayer wave component (0.03-0.15 Hz) did not change with the time of day, but it increased 90 min after food intake in both supine and standing positions (P less than 0.01 and P less than 0.05, respectively). These data suggest that supine vagal cardiac control during the waking period increases in the morning and decreases 30 min after food intake and that sympathetic cardiac control increases 90 min after food intake.

The coupling constant KL is the most important parameter of the DFB-LDs. However there have been very few reports so far on the relation between the characteristics of the DFB-LDs and KL because of the difficulty of the control of K L. We have investigated the dependences of the slope efficiency/the s pectral linewidth/the relative intensity noise/the harmonic distortion of the DFB-LDs on K L systematically, using Buried Grating structure. The experimental results have shown good agreement with theoretical ones. These may provide useful guiding principle for t he designing of DFB-LDs. The devices studied in this work were 1.3pm Buried Grating Type Distributed Feedback P-substrate Partially Inverted Buried Heterostructure Laser Diode (BG-DFB PPIBH LD)[ll(see Fig.l), whose K L can be accurately controlled. The rear and front facet reflectivities were 80% and 1%. The cavity length was 300pm. Fig.2, Fig.3, Fig.4 and Fig.5 show the dependences of slope efficiency from the front f acet 7 f, spectral linewidth A v, relative intensity noise (RIN), and second order harmonic distortion H2 on K L, respectively. The theoretical curves (averaged value and standard deviations by the grating phase at the facets) are shown in the f igures. The calculated lines explain the measured results very well except for the H2. Note that the theoretical curves in Fig.5 are the standard deviation of the optical intensity aOPT along the laser cavity. High slope efficiency is obtained with small K L due to weak feedback by the grating which brings a strong photon emission from the cavity. Narrow linewidth is attained with large K L due to strong feedback which results in the increase of the optical intensity in the c avity. Low noise is achieved by large KL due to strong feedback which increases t he stimulated emission photon number, against the spontaneous emission photon number. H2 is defined by the intensity ratio of 2f to f, where f is the modulation frequency. H2 is minimized at K f, -1, which correlates the behavior of COPT. The large aOPT may cause the spatial hole burning[2] which generates non-linearity of P-I curves at low frequency region.

A case of orbital emphysema as a sequel of a snowboard related head injury is reported. It is believed that a fracture of the medial orbital wall was caused by the increased intraorbital pressure when the patient hit his forehead on the snowy ground, allowing air to enter the orbit when he blew his nose. Wearing goggles may prevent this type of sports related injury.

A microcavity structure has been fabricated in which a polyimide layer with thickness on the order of the wavelength of light was sandwiched in between dielectric mirrors by using vacuum deposition polymerization (VDP). We deposited a 330-nm-thick polyimide layer through a polymerization reaction between two mutually reactive monomers evaporated onto a dielectric mirror consisting of TiO2/SiO2 multistacks. In the middle of the VDP process we deposited tris(8-hydroxyquinoline) aluminum (ALQ) so that a sublayer 30%-doped with ALQ was inserted within the polyimide layer. Upon the polyimide layer we coated a dielectric mirror consisting of Ta2O5/SiO2 multistacks. The mirrors were designed to have a broad high reflection band (stop band) with a reflectivity maximum of ∼90% at 530 nm. Fabrication of a microcavity was considered to be successful based on its optical properties. Within the stop band a sharp transmission band with a width of 8 nm appeared due to Fabry–Perot resonance. Correspondingly, ALQ photolum...

Leakage current in p-substrate 1.3 μm InGaAsP/InP Buried Crescent (PBC) lasers has been examinedcompared with n-substrate Buried Crescent (BC) lasers. It has been found that the value of the leakage currentcan be estimated by dV/dI-I (differential resistance vs. current) curve above threshold. The leakage current intypical PBC laser is about one order of magnitude smaller than that in BC laser, in which the leakage currentbecomes a few 10 mA at high temperature (70-80°C) and degrades remarkably the P-I (light output power vs.current) characteristics. In order to achieve excellent characteristics at high temperature and high power levels, it is important to minimize the current flowing into p-blocking layer adjacent to the active region.

A 1-µm 256K MOS RAM has been fabricated using a variable-shaped electron-beam (EB) direct writing technology. EB drawing data are prepared using a new program, PEBL, which includes a new algorithm for shot division. PEBL plays an important role in obtaining high EB system throughput and high quality patterns. A new proximity correction technique, DCA, has also been proposed. This technique is simple and very effective in fabricating 1-µm VLSI patterns. Negative resist CMS or positive resist FPM are used appropriately, according to process levels. In fabrication of a 1-µm 256K MOS RAM, ±0.2-µm overlay accuracy and ±0.1-µm linewidth accuracy were achieved.

High performance of newly developed InGaAsP P-substrate buried crescent (PBC) laser diodes is described. It is shown that the PBC laser has superior characteristics to the conventional buried crescent (BC) laser with n-InP substrate. The maximum output power of 140 mW under a CW condition is realized at room temperature. CW light output power of 10 mW up to 110°C is achieved. A maximum CW temperature of 135°C is obtained. Stable CW operations have been confirmed in 70°C 5-mW and 70°C 20-mW aging tests. The reason for the high performance is discussed in relation to the leakage current which flows through the current blocking layers.

Laser diodes with the p-substrate buried-crescent structure have been fabricated for the 1.2-1.55- mu m wavelength region. The dependence of laser characteristics on wavelength has been measured. Up to 70 degrees C, the increasing rates of the threshold current with temperature are similar, while, above 70 degrees C, a shorter-wavelength laser shows a larger increasing rate. At the same full width at half maximum of the far-field pattern perpendicular to the junction plane, the external differential quantum efficiency of the 1.55- mu m laser diode is only 10% smaller than that of the 1.3- mu m laser. The absorption loss coefficients in the active layer of the 1.2-, 1.3-, and 1.55- mu m laser are estimated to be 26, 34, and 73 cm/sup -1/, respectively. >

1. 1. The H 1 receptor blocking agents (H 1 blockers) (promethazine, diphenhydramine, chlorpheniramine and tripelennamine) but not H 2 blockers (burimamide and metiamide) were able to relax the rabbit cerebral, coronary and mesenteric arteries which were contracted with potassium (30 mM). However, these agents failed to decrease the active tension of rabbit aortic strips. 2. 2. Promethazine was the most potent vascular relaxants among the agents tested. In addition, the potencies of the H 1 blockers were higher in cerebral arteries than in the coronary and mesenteric arteries. 3. 3. H 2 blockers also did not alter either the relaxing response to H 1 blockers or the contractile effect of histamine on the cerebral arteries. Propranolol did not inhibit the relaxing effect of H 1 blockers. 4. 4. Although the mode of relaxing action of H 1 blockers is not clear it may be due to the direct action on the vascular smooth muscle.

Stable high-power CW operation of 1.3-μm InGaAsP/InP p-substrate buried crescent laser diodes (PBC-LD'S) has been realized, by controlling the front and rear facet reflectivities of the laser diode chips. The front facet reflectivity is reduced to 17 percent and the rear facet reflectivity is increased to 90 percent, by evaporating multilayer dielectric films (Si/Al 2 O 3 SiO 2 :17 percent, SiO 2 /Si/SiO 2 /Si/SiO 2 :90 percent) on each facet. CW light output power of 50 mW is achieved up to 60°C. Aging tests have been carried out under automatic power control (APC) mode conditions of 50°C-30 mW, 40 mW, 50 mW, and 30°C-50 mW. All samples are operating stably in spite of junction-up configuration. The lifetimes are estimated to be more than 2 \times 10^{4} h for all conditions.