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We investigated an optical carrier injection mechanism in an organic semiconductor rubrene crystal. We simultaneously measured exciton photoluminescence (PL) and photocurrent under an electric field higher than 1 kV/cm at room temperature. An anti-correlation between the exciton PL intensity and photocurrent was observed. This directly indicates that carriers are generated through an exciton dissociation induced by the electric field. The estimated exciton dissociation efficiency is on the order of 10−2 for an excitation wavelength of 442 nm under an electric field of 12 kV/cm at room temperature. In addition, we revealed that both carriers and excitons are trapped at oxidation sites at the surface area of the crystal and more efficiently emit a modified luminescence.

We performed photocarrier injection by two-photon excitation in rubrene crystal using laser pulses of nanosecond-duration at various wavelengths under an external electric field. Based on the excitation spectra, it is revealed that photocarriers are injected at excitation energies corresponding to the intrinsic absorption by two-photon process, in contrast to the midgap-states-mediated injection by one-photon process. This result means that the two-photon excitation method is useful to inject photocarriers free from the surface traps.

Introduction/Background Rehabilitation Robots for improvement of gait dysfunction with neurological deficits have been developed to regain the adequate gait control Motor relearning with repetition of assisted motion by robotic devices is assumed to be able to make the efficient motor kinematics and kinetics However, it is not clear what changes with the motor control via motor relearning process with using robot devices occur during walking in this population In general, the nerve system was considered to control the motion using a low-dimensional modular organization of muscle activation We aimed to clarify the effect of the robots for muscle synergy control using non-negative matrix factorization. Material and method Robot Knee Ankle Foot Orthosis (RKAFO) that can control the knee motion during gait was used as robot device to assist to normalize gait kinematics In 8 participants after stroke, EMG signals from ten leg muscles on both sides were measured before and after robot assist walking for 3 minutes at self-selected speed. Results The number of modules on paretic side was less than that on non-paretic side Furthermore, fewer modules were needed to be account for muscle activation in walking before robot assist than after robot assist The number of fractionated synergy from before to after assisted gait related to the increase of gait speed by using RKAFO. Conclusion Our results suggest the muscle synergy coordination during walking was changed with normal motion induced by using robot assist in post-stroke subjects And also, increase in number of fractionated synergy was related with higher gait function.

This paper describes a new inclinometer that compensates for ultralow-frequency acceleration disturbances. This inclinometer consists of a low-cost accelerometer, pendulum, and rotary encoder. The key feature of this inclinometer is the estimation method used to calculate the pendulum's inertial angle. We propose two algorithms to estimate the pendulum's angle. Algorithm I uses time-averaged accelerations and some assumptions. Algorithm II applies the pendulum's equation of motion. The results of simulations and experiments confirm that both algorithms can achieve highly accurate level/angle estimations under acceleration disturbance conditions. We apply this inclinometer to an autotracking antenna system for vessels. Time simulations verify its effectiveness.

There is a significant learning curve for endoscopic submucosal dissection of esophageal neoplasms that has not been fully characterized. This retrospective study included 33 consecutive superficial esophageal neoplasms for analysis of the learning curve for esophageal endoscopic submucosal dissection based on a single, novice endoscopist's experience. The study was divided into three periods (T1, T2, and T3) of 10 endoscopic submucosal dissection procedures in chronological order, with 13 procedures in the last period. Patient factors (age, sex, coexistent esophageal varices, or submucosal fibrosis) and tumor factors (location at upper esophagus, involving3/4 esophageal circumference) for endoscopic submucosal dissection were not statistically different between the periods. The mean procedure time was 74.6 min/cm(2) , 23.4 min/cm(2) , and 10.5 min/cm(2) for T1, T2, and T3, respectively. The procedure time decreased over time (P = 0.02) and post hoc test revealed significant difference was only between T3 and T1 (P = 0.019). The en bloc resection rate was 50%, 100%, and 92.3% for T1, T2, and T3, respectively (P for trend = 0.015). R0 resection rate was 40%, 100%, and 84.6% for T1, T2, and T3, respectively (P for trend = 0.023). Two patients had complications: each one patient in T1 and T3 period experienced major bleeding during the procedure (P for trend = 0.875). None of the patients had esophageal perforation. The results of the study concluded that at least 30 cases of endoscopic submucosal dissection of esophageal neoplasms are needed for a novice endoscopist to gain early proficiency in this technique.

To survey the applicability of existing HTS wires for SMES, five kinds of cryocooler-cooled HTS coils were fabricated and tested to estimate fundamental characteristics of HTS wires. Critical current, run-away current, and ac losses were measured. To confirm the effect of electromagnetic force to the coil performances, critical currents were measured under high magnetic fleld of 14 T with liquid helium cooling. The HTS wires used for the coils are three types of Bi2212 wire and two types of Bi2223 wires. We have wound these wires to little coils of 14 cm outside diameter, 10 cm height with cryocooling. As a result, a difference of critical current characteristic of a Bi2212 wire and a Bi2223 wire was not big at the temperature of 20 K, but a critical current of a Bi2212 wire fell at 50 K greatly, and the HTS-SMES design that utilized a temperature margin by cryocooler-cooled system understood what a Bi2223 wire was suited for.

We report a case of synovial sarcoma in the neck that was initially considered to be a benign soft-tissue tumour. The mass appeared to originate in the perivertebral space, extending to the spinal canal via the C3/4 and C4/5 neural foramina. The mass also encased the right vertebral artery and this suggested a malignant soft-tissue tumour.

Aim Physical growth in neurologically healthy preterm infants affects motor development. This study investigated the separate relationships between muscle and fat in infancy and later motor development and physical growth. Methods Muscle thickness and subcutaneous fat thickness of the anterior thigh were measured using ultrasound images obtained from neurologically healthy preterm infants at birth, 3, 6, 12 and 18 months' corrected age. We also obtained the Pediatric Evaluation of Disability Inventory and Alberta Infant Motor Scale scores at 18 months' corrected age to assess motor ability and motor delay. Results Thirty preterm infants completed the study protocol. There was a significant positive correlation between motor ability and increments in subcutaneous fat thickness during the first 3 and 6 months' corrected age (r = 0.48 and 0.40, p

A unicellular organism, Paramecium, exhibits circadian rhythm activities in many physiological phenomena, i.e., mating reactivity, photoaccumulation in Paramecium bursaria and mating type reversals in Paramecium multimicronucleatum. In this study, we used an image-processing system to analyze swimming activity in a population of Paramecium multimicronucleatum cultured axenically under 12 h-light/12 h-dark cycles (LD 12∶12). Swimming behavior was recorded both under LD 12∶12 and constant darkness and images tracing the tracks of Paramecium were produced every 4 min. Swimming activity was represented by the occupied area by the tracks relative to the total observed area. It is high during daytime and low at night and exhibits a freerunning rhythm in constant darkness. Furthermore, criteria for two major components of swimming behavior, straight and circle swimming, were established and analyzed. The results indicate that swimming behavior alters depending on the time of day: straight swimming increased during the day and circling was dominant around dusk both under LD 12∶12 and constant darkness.

The title reaction initially produced a mixture of three cyclic oligomers, calix[n]resorcinarenes (n= 4, 5, 6), as the major products. Under the conditions of their formation, the pentamer rapidly isomerized to the tetramer and the hexamer, while the hexamer slowly isomerized to the tetramer. A new cyclic oligomer, calix[5]resorcinarene, was isolated and characterized.

Electron, negative ion, and positive ion densities in a capacitively‐coupled radio‐frequency (rf, 13.56 MHz) SF6 plasma have been investigated as functions of the pressure (30–700 mTorr) and rf power. The decay of the charged particle densities in the afterglow has also been studied to obtain information about their kinetics. The electron density was determined by using a microwave cavity resonance technique. Negative ions were detected by measuring the density of photodetached electrons produced by pulsed laser irradiation of the plasma. The positive ion density was obtained from Langmuir probe measurements. At a rf power of 0.13 W/cm2 and at low pressures (≲100 mTorr) the positive ion density, which is virtually equal to the negative ion density, is found to be larger than the electron density by a factor of a few hundred; the ion/electron density ratio increases with increasing pressure to reach a value of a few thousand at high pressures. Wavelength‐dependent photodetachment measurements indicate that...

Human herpesvirus-6 (HHV-6) is a major cause of limbic encephalitis with a dismal prognosis after allogeneic hematopoietic stem cell transplantation (SCT). Because our previous trial of preemptive therapy with foscarnet sodium (phosphonoformic acid; PFA) failed to prevent HHV-6 encephalitis, we conducted a prospective study to examine the safety of prophylactic PFA administration and elucidate the changes in the plasma HHV-6 DNA levels in the early post-SCT period. Plasma HHV-6 DNA was measured thrice weekly from day 6. PFA, 90 mg/kg/day, was administered from days 7 to 21 after bone marrow or peripheral blood SCT and to day 25 after umbilical cord blood transplantation. Of the 10 patients enrolled, 2 dropped out of the study, 1 because of early death, and 1 with a low glomerular filtration rate. Grade 3 or greater adverse events occurred in 9 of the 10 prophylactic PFA patients and in 7 of the 10 control patients who had clinical backgrounds similar to the study subjects and underwent SCT during the same period. Neurological disorders developed in none of the study subjects but in 4 of the 10 control patients, including 2 with HHV-6 encephalitis. HHV-6 reactivation occurred in 3 of the 10 study subjects. The prophylactic PFA regimen was thus safe and it may reduce the risk of limbic encephalitis, but is not considered to be potent enough to prevent HHV-6 reactivation.

The title reaction initially produced a mixture of three cyclic oligomers, calix[n]resorcinarenes (n= 4, 5, 6), as the major products. Under the conditions of their formation, the pentamer rapidly isomerized to the tetramer and the hexamer, while the hexamer slowly isomerized to the tetramer. A new cyclic oligomer, calix[5]resorcinarene, was isolated and characterized.

The crystal structures of YBa2Cu3O7−x thin films deposited on MgO(100) substrates have been investigated by cross-sectional transmission electron microscopy (TEM). At a substrate temperature of 670 °C, Cu–O chains become wavy. Stacking faults are formed between the Cu–O chains. Therefore, the domains with c-axis lattice constants of 15 Å, 27 Å, and 39 Å are observed. By applying a biasing voltage of + 300 V, deviation in the c-axis orientation is reduced compared to that at an unbiased condition; even some grain boundaries remain. Near substrate surfaces, deviation of the c-axis direction from the substrate normal increases with a decreasing substrate temperature from 700 °C to 670 °C. Application of a substrate bias voltage of +300 V improved the heteroepitaxial growth of the c-axis oriented YBa2Cu3O7−x.

Magnetic circular dichroism (MCD) in superconducting and insulating YBa 2 Cu 3 O x thin films is studied. The MCD spectra in superconducting samples exhibit a linearly field dependent structure at 4–5 eV. The field and temperature dependences, the latter seeming to obey the Curie law, suggest that this structure is associated with the intraionic 3d-4p transitions of localized Cu ions at the Cu-O chains. These transitions are thought to be the origin of the peak at 4.1 eV observed in insulating ones. A comparison of the spectra of insulating YBa 2 Cu 3 O x dielectric function studies and this work is also given.

The dependence of the crystal orientation of YBa 2 Cu 3 O 7-x deposited using an ArF pulsed laser on the post-deposition oxygen partial pressure during cooling was studied. The crystal orientation of films deposited in low oxygen partial pressure was found to change depending on the oxygen partial pressure during cooling after deposition, accompanied by solid phase regrowth. In order to investigate this regrowth behavior, films of different thickness were fabricated by an Ar ion beam-thinning technique, and magnetization measurements were performed.

Chemical mediators responsible for the antigen-induced contractions of isolated, passively sensitized human and guinea pig lung parenchymas and bronchi or tracheas were evaluated by several antagonists and enzyme inhibitors, with emphasis on the effects of the potent and selective peptide leukotriene (p-LT) antagonist MCI-826. All of these preparations showed long-lasting contractions in response to an antigen challenge which lasted for more than 60 min. In either the human lung parenchyma and brochus or guinea pig lung parenchyma, pretreatment with 10(6) g/ml (2.4 x 10)-6) M) MCI-826 significantly inhibited the late phase at 10 to 60 min after the challenge of the contraction following slight suppression of the early phase. The early phase contractions of these preparations were moderately antagonized by 10(-6) g/ml mepyramine, but the late phases were not influenced or even rather enhanced. The combination treatment of MCI-826 with mepyramine additionally and markedly inhibited both phases of these preparations. On the other hand, although mepyramine apparently inhibited the early phase of the guinea pig tracheal contraction but not the late phase, no synergistic inhibitions of the contraction were observed when it was combined with MCI-826. The p-LT antagonist FPL 55712, atropine and indomethacin at 10(-6) g/ml either slightly inhibited or enhanced the contractions of human lung parenchymas, guinea pig tracheas and lung parenchymas, but the effects were not significant. From these results, it should be emphasized that p-LTs largely contribute to induction of the anaphylactic contractions of human lung parenchymas as well as human bronchi and guinea pig lung parenchymas but not guinea pig tracheas.

Bias effects on the preparation of superconducting thin films by pulsed laser deposition have been investigated by means of time-of-flight mass spectroscopy. Since a large number of electrons were emitted from the target at the same time as ions during ablation, ions in the plume are shielded from the external electric field by electrons and are not influenced by substrate biasing. Under positively biased conditions, the electron emission was greatly enhanced. Multivalenced ions (Cu/sup 2+/ and Cu/sup 3+/) were also observed in these conditions. It can be understood qualitatively that the rapid extraction of electrons from the target surface by the electric field tends to generate the multivalenced ions. It was also found that the multivalenced ions have an energy of more than 250 eV, which is higher than that of the other atomic ions. Energy differences between the atomic and molecular ions have been observed. While the former have energies of about 200 eV, the latter have energies of a few tens of electronvolt. This indicates that the atomic ions are accelerated in the initial laser ablation process and that the molecular ions are produced in the plasma reactions in the plume. Cluster ions of the mass number of several hundreds were also observed and also had energies of a few electronvolts. It was also found that the laser plume of the YBa/sub 2/Cu/sub 3/O/sub 7- delta /, target is poor in the CuO/sup +/ ion compared to the plasma of other metals.

This paper describes novel rapid thermal annealing for GaAs wafers under vacuum conditions (VRTA) using a three‐zone lamp power control method. The developed RTA technology eliminates generation of crystallographic slip lines and wafer deformation due to the convection effect caused by ambient gas. A three‐zone lamp power control method produced excellent uniformity in the activated layer, presenting the best data ever attained by RTA. Also, numerical simulation demonstrates improved temperature uniformity achieved by a three‐zone lamp power control method which reduces the edge radiation effect. Moreover, we have found that VRTA technology is particularly effective for annealing large‐size GaAs wafers, which are more easily deformed or slip‐lined than 2‐in. wafers. We have applied VRTA to fabricating ion‐implanted n+ contact regions for self‐aligned 0.5‐μm‐gate doped‐channel hetero‐metal‐insulator‐semiconductor field‐effect transistors with a lightly doped drain, and have obtained excellent Vt uniformity...

Oxygen partial pressure during cooling after deposition dependence of crystalline orientation of ArF pulse laser deposited YBa2Cu3O7−x was studied. The crystalline orientation of films deposited in a low oxygen partial pressure was found to change dependent on oxygen partial pressure during cooling after deposition by regrowth in solid phase. In order to investigate the regrowth behavior, magnetization measurements were carried out with respect to films of different thickness fabricated by an Ar ion beamthinning technique.

The magnetic flux behavior in YBa 2 Cu 3 O x specimens under various applied fields was observed at 10K and 77K using the Faraday effect of an iron garnet film with stripe magnetic domains. The magnetic flux distribution was determined by optical observation of the domain structure in the iron garnet film placed on the sample. The magnetic flux gradients in a crystal fabricated by the Melt-Powder-Melt-Growth (MPMG) method and in a thin film were in good agreement with those predicted by the critical state model at both 10K and 77K. On the other hand, in a sintered sample the flux penetrated through the superconducting weak-link regions, and no flux gradient was observed at 77K.

We have developed a new channel allocation algorithm for use with a new Ku-band mobile satellite communication system that is being developed as a separate piece of work. The system enables new Earth stations to use a low cost polarization tracking free antenna. To expand system flexibility, the new Earth stations and conventional earth stations are hoped to share a satellite transponder. However, the problem is that the satellite transponder sharing significantly increases cross polarization interference. Our algorithm overcomes the problem. It takes into account station types and maintains assigned channels so as not to increase cross polarization interference and to reduce wasteful bandwidth gaps in the satellite transponder. We simulated channel allocation under various traffic conditions on a computer in order to test our algorithmpsilas performance. The results showed that our algorithm can increase the accommodation number of stations and achieves a low cross polarization interference.

We proposed a novel in-orbit antenna pattern measurement method. We measured ETS-VIIIpsilas onboard antenna pattern using the proposed method. We confirmed that the measured and calculated patterns were in good agreement. Our method offers high accuracy measurements as well as short measurement times.

A computation method has been developed for predicting the temperature of a tunnel during an arbitrary year (e.g. 30 years hence), taking into account the thermal capacity of the soil and the annual load variation. The results showed that, if the depth of burial of the tunnel is great, the thermal time constant for soil temperature elevation is large, and thus 30 years or more are required to reach saturation. Moreover, if the annual load variation is not taken into account, then a considerable overestimate may occur. In order to ascertain the validity of these theoretical results, measurements along an actual power line were performed, and the results so obtained agree well with the theoretical values for both short (approximately one week) and long (approximately three years) periods. >

New EHV XLPE (extremely high-voltage cross-linked polyethylene) cable technologies have been developed and applied to commercial service. For example, 66/154 kV XLPE cables are currently used in a new underground transmission network. The number of these cables has rapidly increased and their use has proved very satisfactory. A 275 kV XLPE long-distance underground transmission line with straight-through joints is scheduled to go into service in May 1989, while a 500 kV XLPE cable was put into operation in July 1988 as a lead cable in the Imaichi pumped storage power station. Other technologies have been developed for practical application, including 66/154 kV segmental insulated strand conductor XLPE cables for larger capacity and compact-type oil-stop joints between oil-filled (OF) and XLPE cables for partial replacement of deteriorated OF cables. >

Cl2 chemical dry etching for GaAs substrates of {111}A, {111}B, {110} and {100} orientations was accomplished under high vacuum conditions. The etch rate for different substrate orientations was {111}B > {110} = {100} > {111}A for temperatures below 450° C, and was nearly equal for temperatures above 450° C. For {111}B, {110} and {100} substrates, the etch rate depends strongly on the substrate temperature above 450° C and below 150° C. Two activation energies for etching (10.0 kcal/mol below 150° C and 16.0 kcal/mol above 450° C) were obtained. Between 150 and 450° C, the etch rate depends weakly on the substrate temperature. However, for {111}A substrate, the etch rate increased monotonically with increasing substrate temperature above 300° C. The activation energy corresponds to that for the other substrates above 450° C. These results are caused by the surface chemical reaction of GaAs/Cl2. By using these etching properties, a vertical side wall was fabricated without ion bombardment.

We propose an efficient channel control scheme for gathering data from many observation points scattered over an ultra-wide area using a satellite communication system. There are a huge number of observation points, and the data packets to be transmitted are relatively short. To implement the system economically, the proposed scheme is expected to manage tons of channels correctly without large control signal overhead even if there are bit errors on the satellite link. Most of the observation points acquire pre-scheduled (PS) data such as rainfall and temperature measurement, while a few of them acquire event-driven (EV) data such as landslides and earthquake tremors. A pre-assigned channel access scheme will be adequate for the PS-type data. However, it is difficult to assign a channel for EV data before an event because the events to be transmitted are not predictable. Therefore, we propose a channel access scheme that is built on a pre-assigned scheme but also has an immediate and reliable scheme alternation process to accommodate EV data gathering. Performance evaluations showed that the proposed scheme greatly increases accommodation capacity and throughput compared with the conventional schemes in various observation point situations and link error conditions.

We propose a simple configuration, low coupling gap-filler that can re-transmit signals at the same frequency in which they were received to enhance service areas for next-generation satellite communication networks. To suppress coupling between the receiving and transmitting antennas, this gap-filler uses two transmitting antennas that form a null in the direction of the receiving antenna by controlling the amplitude and phase of one transmitting antenna. Results of simulations and field experiments show that the proposed on-frequency gap-filler is feasible and can greatly suppress coupling

We study the behavior of a confined stream made of two immiscible fluids when it reaches a T junction. Two flow patterns are witnessed: the stream is either directed in only one sidearm, yielding a preferential flow pathway for the dispersed phase, or splits between both. We show that the selection of these patterns is not triggered by the shape of the junction nor by capillary effects, but results from confinement. It can be anticipated in terms of the hydrodynamic properties of the flow. A simple model yielding universal behavior in terms of the relevant adimensional parameters of the problem is presented and discussed.

This paper reports a high performance V-band MMIC dielectric resonator oscillator (DRO). The DRO utilizing a 0.15 /spl mu/m gate AlGaAs/InGaAs heterojunction FET has exhibited stabilized oscillation with low phase noise of -88 dBc/Hz at 100 kHz off-carrier and the output power of 3.7 dBm at 55.135 GHz. The oscillation frequency stability of -1.9 ppm//spl deg/C was obtained with a dielectric resonator of +3.3 ppm//spl deg/C temperature coefficient.

A low noise GaAs FET amplifier provided with the noise temperature of less than 140K (NF: 1.71 dB) at -50/spl degree/C over 1 I .7 - 12.2 GHz band was developed using GaAs FET's with a recess structure and MIC technology.

Recently developed LNAs incorporating two dimensional electron gas (2 DEG) FETs for satellite communications earth stations are disclosed, which give epoch-making low noise as FET LNAs to operate. in the 2, 4, 12, and 20 GHz bands at room temperature, especially under cooled state. Typically detailed further is newly developed 4 GHz band LNA with 55 K max. noise temperature at room temperature, noise temperatures of the order of 30 K across 800 MHz bandwidth (3.4 to 4.2 GHz) under thermoelectrically (TE- ) cooled state (about-45°C), which has been adopted in the new earth station conducted by KDD.