7 research outputs found

    Laser ranging application to time transfer using geodetic satellite and to other Japanese space programs

    Get PDF
    Communications Research Laboratory (CRL) has been developing a laser time transfer system using a satellite laser ranging (SLR) system. We propose Japanese geodetic satellite 'AJISAI', launched in 1986 as a target satellite. The surface is covered not only with corner cube reflectors but also with mirrors. The mirrors are originally designed for observation of flushing solar light reflected by the separate mirrors while the satellite is spinning. In the experiment, synchronized laser pulses are transferred via specified mirror from one station to another while the satellite is up on the horizon to both stations. The system is based on the epoch timing ranging system with 40 ps ranging precision, connected together with UTC(CRL). Simulation study indicates that two stations at thousands of km distance from each other can be linked with signal strength of more than 10 photons and the distributed images of laser beam from AJISAI mirrors give many chances for two stations to link each other during a single AJISAI pass. Retro-reflector In Space for Advanced Earth Observation Satellite (ADEOS) and RendDezVous docking mission of Experimental Technology Satellite-7 (ETS-7) are briefly presented

    Surgical outcomes in cases of postoperative recurrence of primary oral cancer that required reconstruction

    Get PDF
    [Purpose] In order to clarify prognostic factors of recurrent oral cancer,[Patients and Methods] In 17 oral cancer patients with their age ranging from 28 to 86 years old, who underwent extensiveresection accompanied by reconstruction for recurrence of a primary oral cancer, correlations between survival rate after salvage surgery and subsite, T classification and N classification of their initial and recurrent tumors, and time of recurrence were analyzed by using Kaplan-Meier method and kai-square analysis. [Results] Tongue cancer (10 patients) was found to have the poorest prognosis among all the subsites, and especially those whohad recurrence within 3 months after previous surgery had extremely poor prognoses; 30% (3/10) of them died without being discharged from the hospital after salvage surgery, and in 40% of them QOL was remarkably impaired losing their voice andchance of peroral food intake, etc. While T classification and N classification of initial and recurrent tumors were found to have no correlations with the prognosis. [Conclusion] More appropriate and realistic information should be provided to those patients to assist them to make a fully informed decision prior to surgery

    Effects of a tongue-holding maneuver during swallowing evaluated by high-resolution manometry.

    Get PDF
    OBJECTIVE: This study aimed to investigate the effects of a tongue-holding maneuver (THM) during swallowing using a novel high-resolution manometry (HRM) system. STUDY DESIGN: Case series with planned data collection. MATERIALS AND METHODS: Thirty-three asymptomatic Japanese adults were studied. A solid-state HRM assembly with 36 circumferential sensors spaced 1-cm apart was positioned to record pressures from the velopharynx to the upper esophagus at rest and during swallowing. The maximum values of the dry swallowing pressures at the velopharynx, mesohypopharynx, upper esophageal sphincter (UES), and distance from the nostril to each point of maximum values with and without the THM were measured. RESULTS: The distance from the nostril to the UES was statistically shorter when swallowing with the THM than without the THM (paired t test, P=0.009). The maximum pressure at UES was greater when swallowing with the THM than without the THM, although there was no statistically significant difference (paired t test, P=0.051). There was no difference in the pressures and the distance between swallowing with or without the THM at any other site. CONCLUSIONS: These findings suggest that the THM may not have a potential to facilitate compensatory swallowing power when swallowing

    <Session 4: Biomedical Application>UWB Body Area Network to Medical Vital Sensing in hospital, homes and combined Satellite Communication

    Get PDF
    19–22 May 2022 Kyoto, JapanWe investigated advantages and drawbacks of wireless BAN (Body Area network) systems using UWB(Ultra Wide Band) wireless technology that are expected robustness against interference, low power consumption, and little interference to a body for healthcare. Two types of low and high frequency bands for UWB were examined using various vital sensors for hospital and home bedside monitoring. The high band UWB BAN system with TDMA protocol in MAC worked well to prevent interference. The most important drawbacks was shadowing problem when changing the position of body on the bed. We confirmed by experiments that shadowing can be prevented by selecting proper antenna and setting a coordinator near the ceiling and another coordinator under the bed. We also examined the combined high band prototype of UWB-BAN with WINDS satellite communication link to perform real transmission of UWB-BAN vital data and DICOM CT slice image, assuming the case of disaster when the land communication is damaged. No packet loss was experienced during two hours. Round trip time from KASHIMA to YRP (Yokosuka) was 610msec with processing delay that is allowable for vital data

    Investigation of pharyngeal swallowing function using high-resolution manometry.

    Get PDF
    OBJECTIVES/HYPOTHESIS: This study aimed to demonstrate the feasibility of a novel high-resolution manometry system, and to establish normal values of swallowing pressures along the velopharynx and upper esophagus. STUDY DESIGN: Prospective study. METHODS: Thirty-three asymptomatic adult Japanese controls were studied. A solid-state high-resolution manometry assembly with 36 circumferential sensors spaced 1 cm apart was positioned to record pressures during swallowing from the velopharynx to the upper esophagus. The maximum values of the swallowing (dry and 5 mL of water) pressures at velopharynx, meso-hypopharynx, and at the upper esophageal sphincter (UES) were measured. The resting UES pressure, the length of the part in the cervical esophagus showing the resting UES pressure, and the distances from the nostril to the above-mentioned points of pressure measurement were also measured. RESULTS: The maximum value of dry and water swallowing pressures at the velopharynx, meso-hypopharynx and UES, and the distances from the nasal vestibulum to each point in men were 141.1 +/- 73.5 (mm Hg, mean +/- standard deviation) and 162.7 +/- 94.9, 175.3 +/- 59.7 and 182.9 +/- 83.6, 172.7 +/- 73.8 and 236.1 +/- 78.9, and 10.0 +/- 1.3 (cm) and 10.1 +/- 1.4, 14.1 +/- 1.5 and 14.4 +/- 1.3, 17.9 +/- 1.7 and 18.0 +/- 1.4, respectively. Those in women were 118.9 +/- 38.0 (mm Hg) and 124.7 +/- 43.4, 165.9 +/- 41.5 and 167.3 +/- 65.0, 149.2 +/- 68.7 and 243.7 +/- 87.4, and 9.5 +/- 1.2 (cm) and 9.4 +/- 1.2, 13.0 +/- 1.5 and 12.8 +/- 1.4, 15.8 +/- 1.5 and 16.0 +/- 1.3, respectively. The maximum value of resting UES pressure, the length of the part in the cervical esophagus showing the resting UES pressure and the distance from the nostril to the mid-point of the width of the resting UES pressure in men and in women were 70.2 +/- 30.0 mm Hg, 4.0 +/- 0.7 cm, 19.1 +/- 1.3 cm, and 61.8 +/- 26.7 mm Hg, 3.6 +/- 0.6 cm, 17.0 +/- 1.2 cm, respectively. CONCLUSION: The present study provides anatomical and physiological information about normal swallowing along the velopharynx and upper esophagus, which will be an aid to the future clinical and investigative studies

    Amplitude and area ratios of summating potential/action potential (SP/AP) in Meniere\u27s disease.

    Get PDF
    CONCLUSIONS: Our results suggest that summating potential/action potential (SP/AP) area ratio may not necessarily have higher sensitivity in the diagnosis of endolymphatic hydrops of Meniere\u27s disease (MD) than SP/AP amplitude ratio in transtympanic electrocochleography (ECochG). OBJECTIVE: Recent studies suggested that SP/AP area curve ratio was more sensitive to endolymphatic hydrops in comparison with SP/AP amplitude ratio in extratympanic ECochG. The purpose of the present study was to evaluate the utility of the SP/AP area curve ratio in transtympanic ECochG for the diagnosis of MD. PATIENTS AND METHODS: A retrospective chart review of 198 patients (209 ears) was conducted in cases of MD. RESULTS: With regard to SP/AP amplitude ratio, 57.1% in definite cases of MD (group 1), 39.6% in probable cases of MD (group 2), and 50.0% in the cases who had transformed from probable MD to definite MD (group 3) showed abnormally high values, respectively. Abnormally high values were observed in 43.9%, 27.7%, and 30.0% in SP/AP area ratio in groups 1, 2, and 3, respectively, indicating that abnormal values were observed more frequently in the amplitude ratio than in the area ratio in all three groups
    corecore