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The 28th Japanese Antarctic Research Expedition has installed a NOAA data processing system at Syowa Station (69°00′S, 39°35′E) and has started the operation. This system is used to obtain cloud and sea ice distribution in the broad area under the project of "Antarctic Climate Research (ACR)", which started in 1987. The main part of the system is composed of a FACOM S3300 mini computer, which is used to acquire the received data of satellite at a real time, to make the calibration to obtain the albedo and temperature, to make a map projection, to display the images and to store the data in computer compatible tapes. Moreover, images of brightness temperature difference and histogram are made to discuss the way to discriminate clouds over the snow and ice surfaces.

Sea ice concentrations are determined from the visible and near infrared albedo of the AVHRR imagery. One method uses only one channel data to interpolate the ice concentration between 0 and 100% corresponding to the open water and the snow cover, respectively. This method yieds an uncertainty owing to the variation of albedo by the surface condition change. Another method uses two-channel data to derive not only the ice concentration but also the ice surface condition and can eliminate uncertainties involved in the first method. The ice surface condition is expressed by "snow coverage". Air photographs are compared with the satellite data. They are helpful to discuss the surface condition of sea ice. Time variations of the concentration and surface condition of summer sea ice are discussed.

As part of the Japanese Antarctic Middle Atmosphere Program (Antarctic MAP), columnar amounts of atmospheric minor constituents such as N_2O, CH_4,CFCl_3,CF_2Cl_2 and HNO_3 were determined from measurements of infrared solar spectra for the period 24 March 1983-29 December 1984 at Syowa Station, Antarctica (69°00′S, 39°35′E). A Fourier-transform-infrared spectrometer was used to measure the solar spectra. The highest apodized resolution of the spectrometer is 0.1(cm)^ (full width at half-maximum), but the resolution of 0.8(cm)^ was adopted in routine operation because of an economy of data processing time and of better signal to noise (S/N) ratio. The accuracy of measurements is estimated from S/N ratios of the obtained spectra; typical errors of measured abundances were ±40,±2 and ±6% for CFCl_3 (at 850(cm)^), N_2O (at 2576(cm)^) and CH_4 (at 6004(cm)^), respectively. A MCT detector (cooled at 77 K) is desirable to attain higher resolutions (∿0.1(cm)^) and larger S/N ratios.

The Japanese Antarctic Research Expedition (JARE) has started the 5-year project of "Antarctic Climate Research (ACR)" from JARE-28 in 1987. This project covers the field of Antarctica among the "World Climate Research Program (WCRP)", and aims at knowing the climate change in the Antarctic and clarifying the role of Antarctica in the global climate. Interannual variation of Antarctic atmosphere and air-sea ice interaction are set as the main subjects. In JARE-28,3 major items of observation were carried out under the subject of interannual variation of Antarctic atmosphere. 1) Cloud-radiation climatology : Cloud and sea ice distributions were observed by the NOAA satellite. Radiation measurements were made at the surface to obtain cloud information and to know the effect of clouds on the surface radiation budget. The surface radiation measurements are compared with satellite data to interpret the meanings of the satellite data. 2) Extention of meteorological observing area : The surface synoptic observation was started the newly established Asuka Camp and automatic weather stations were tested at Mizuho Station. 3) Monitoring of minor constituents : Continuous measurements of atmospheric CO_2 content and ozone observations were made.

The Japanese Antarctic Research Expedition operated a three-year project, Polar Experiment South (POLEX-South), from 1979 when the project was limited mainly to the meteorological program, especially the measurements of radiation and vertical profile of temperature and wind in the lowest 30m layer at Mizuho Station (70°42′S, 44°20′E, 2230m above sea level) where katabatic wind blew continuously at a velocity of 12-13 m/s and caused drifting snow. A 30m tower was erected and instrumented in January 1979 and the meteorological program was operational through 1979 and will continue until 1981. The radiation measurements of global shortwave, reflected shortwave, and outgoing and incident longwave were made at the snow surface and at the top of the tower. Direct solar radiation and net radiation were measured only at the snow surface. Temperatures were measured at 15 different levels (7 heights, surface, 7 subsurfaces). Wind velocities and wind directions were measured at 7 levels and 2 levels, respectively. Drifting snow flux, thermal flux in snow, dew point temperature and pressure were also measured. The recording system included a micro-computer, a data logger, transducers, magnetic tape recorders, analog recorders and printing instruments. The measured values were sampled every minute and recorded by magnetic tape recorder and analog recorders. This paper mainly describes the installation and performance of the meteorological system set in a cold katabatic wind area such as Mizuho Station.

A simple regression method is applied to derive the total ozone amount from the TOVS data of TIROS-N/NOAA meteorological satellites received at Syowa Station, Antarctica. Besides channel 9 located in the ozone 9.6μm band, channels 1,2,3 and 8 of HIRS/2 are used. Regression coefficients are determined against Dobson measurements at Syowa Station. Data from 50 orbits of NOAA-6 and -7 are analyzed for 1981-1982. RMS errors of retrieved ozone amounts are 3 to 13 DU ((10)^・atm・cm) at Syowa Station. Horizontal distributions of the total ozone amount are also given and fairly good agreements are seen at the South Pole between the ozone amounts derived from satellites and ground Dobson measurements.

A new apparatus for in situ continuous measurements of atmospheric CO_2 concentration at Syowa Station, Antarctica was developed using a non-dispersive infrared CO_2 analyzer with a precision better than ±0.01ppm. Standard gases employed were CO_2 in air mixtures and their concentrations were determined against special gases with absolute accuracies around ±0.1ppm, which were prepared gravimetrically using an extremely precise balance.

Background Autopsy studies have reported that rupture of a thin-cap fibroatheroma and subsequent thrombus formation is the major mechanism leading to acute coronary syndrome (ACS). However, it is not clear why only some plaque ruptures lead to ACS. Optical coherence tomography (OCT) is a high-resolution imaging modality which is capable of investigating detailed coronary plaque morphology in vivo. The objective of this study was to determine whether ruptured plaque morphology assessed by OCT differs between asymptomatic coronary artery disease (CAD) and non-ST elevation acute coronary syndrome (NSTEACS). Methods We examined ruptured plaque morphology using OCT in 80 patients, 33 with asymptomatic CAD and 47 with NSTEACS. Results The frequency of lipid-rich plaque and intracoronary thrombus was significantly lower in asymptomatic CAD than in NSTEACS (61% vs. 85%, p = 0.013 and 9% vs. 83%, p < 0.001, respectively). Although maximal ruptured cavity cross-sectional area (CSA) was similar in both groups, lumen area at the rupture site and minimal lumen area were significantly larger in asymptomatic CAD than in NSTEACS (3.78 ± 1.50 mm² vs. 2.70 ± 1.55 mm², p = 0.003 and 2.75 ± 0.99 mm² vs. 1.72 ± 0.90 mm², p < 0.001, respectively). Conclusions OCT revealed that the morphology of ruptured plaques differs between asymptomatic CAD and NSTEACS in terms of lumen area and the frequency of lipid-rich plaques and thrombi. These morphological features may be associated with the clinical presentation of CAD. [ABSTRACT FROM AUTHOR]

The relation between albuminuria and coronary microvascular function in patients with chronic kidney disease (CKD) has not been fully investigated. Therefore, we sought to assess whether albuminuria is associated with coronary flow velocity reserve (CFVR) impairment in patients with CKD. Coronary flow study was prospectively performed in 175 patients with CKD. CFVR of the left anterior descending artery was measured to evaluate coronary microvascular function using transthoracic echocardiography. We divided the patients into 5 groups according to the stages of CKD and analyzed the effect of albuminuria. CFVR gradually decreased with an increase in CKD stages. CFVR in patients with albuminuria was lower than those without albuminuria. In groups with CKD stages 2 and 3, the patients with albuminuria showed lower CFVR than those without albuminuria. Multiple logistic regression analysis revealed that albuminuria, age, and gender were independently associated with CFVR impairment. Of these factors, albuminuria was the most powerful predictor with the risk ratio of 12.4 for CFVR impairment. In conclusion, the more the CKD stages progressed, the more severe CFVR was impaired. Albuminuria was associated with CFVR impairment in patients with CKD; even in mild-to-moderate CKD, patients with albuminuria showed further reduced coronary vasodilator capacity. [ABSTRACT FROM AUTHOR]