Monitor of All-sky X-ray Image (MAXI)

Abstract. Monitor of All-sky X-ray Image (MAXI) is the first astrophysical payload which will be mounted on the Japanese Experiment Module (JEM) Exposed Facility in 2004. It is an X-ray all-sky monitor with unprecedented sensitivity to watch the activities of the X-ray sources in the whole sky in every 90 minutes. MAXI is boxshaped in 0.8 x 1.0 x 1.85 m with the weight of 500 kg. The mission life will be at least 2 years. MAXI has two fan-like field of views (FOV), 160 x 1.5 degree each. The X-ray instruments are Gas Slit Camera (GSC) and Solid-state Slit Camera (SSC). The GSC uses gas one-dimensional position sensitive proportional counters with 5340 cm 2 effective area in total and the SSC uses CCDs with 200 cm 2 . Both are capable to detect one-dimensional image, which is used to obtain the locations of the X-ray sources in the FOV along the long direction. Together with the scan which determine the other direction, MAXI can scan almost all sky with a precision of better than 1 degree in the energy range of 0.5-30 keV. The CCD is electrically cooled to -60°C and the camera body is radiatively cooled to -20°C. The CCD chip itself and the radiators may suffer contamination problem. The continuous Ethernet down link will enable us to alert the astronomers in all over the world to the appearance of X-ray transients, novae, bursts, flares etc. We made a test counter and test chips in 1998. Those are being tested in RIKEN, NASDA and Osaka-university. In this paper the test results will be presented, as well as the general description of the MAXI mission

Underweight body mass index is a risk factor of mortality in outpatients with nocturia in Japan

Background: Although nocturia has been reported to increase mortality in elderly individuals, the particular risk factors that are associated with this event are unclear. Therefore, we evaluated risk factors for death in outpatients with nocturia. Methods: Between October 2002 and December 2009, 250 consecutive patients with nocturia were enrolled in two general hospitals in Japan. Among them, 193 patients were able to be followed for at least 1 year and up to 9 years (median 4.8 years) if the patients did not die. Mortality rates and risk factors were evaluated in the nocturic outpatients. Results: Two- and 5-year survival of the nocturic outpatients was 94.6 % [95 % confidence interval (CI) = 92.2-97.1] and 82.6 % (95 % CI = 75.4-87.8), respectively. Higher Charlson Comorbidity Score, lower body mass index (BMI) and lower Physical Component Summary of Short Form-36 item scores were significantly correlated with mortality (p < 0.0001, p < 0.005 and p < 0.05, respectively) in multivariate analysis. The International Prostate Symptom Score, Pittsburgh Sleep Quality Index, Mental or Role/Social Component Summary of Short Form-36 item scores and Nocturnal Polyuria index were not significantly correlated with mortality. The mortality rate was significantly higher in subjects with an underweight BMI (<18.50) compared with a normal range (18.50-24.99) or overweight (≥25.00) BMI [p < 0.00005, hazard ratio (HR) = 5.84, 95 % CI = 2.03-16.8; p < 0.0005, HR = 5.92, 95 % CI = 1.94-18.0]. Conclusions: Additional attention is required for nocturic outpatients with not only a high Charlson Comorbidity Score but also an underweight BMI because of their high mortality. Large prospective studies are warranted to validate this finding and extend more

Collection of patient-generated health data with a mobile application and transfer to hospital information system via QR codes

Background and Objective: The collection of patient-generated health data (PGHD) is important for understanding a patient's daily status for efficient treatment. Mobile applications are effective for continuously collecting patient data, and it is desirable to promptly integrate such data into electronic medical records. However, most hospital information systems have limited connections with external mobile applications. Therefore, in this study, we developed a simple system that can collect data from patients with inflammatory bowel disease (IBD) and transfer the data to electronic medical records without a direct connection to a hospital information system. Methods: We developed patient-facing mobile applications and physician-facing user-defined form templates for the hospital information system. The PGHD were transferred via QR codes using a two-way linkage. The persistence rates were measured and analyzed to clarify the factors affecting the continuous usage of the application. Results: A mobile application connected to a hospital information system was implemented and used in on-site operations. Among patients with IBD using this application, 84.6%–91.7% continued to use it over six months and 72.2%–84.5% continued for over one year. Particularly, patients who used the application during the first two visits tended to be significantly frequent users. Conclusions: We developed a mobile application connected to a hospital information system using a QR code, which is a simple way to continuously collect data from patients and enables physicians to use the data efficiently for patient-centered medical care