積雪融解に伴う花粉濃度ピークの変化

We have investigated the changes in Cryptomeria japonica pollen concentrations in a melting snow cover at different time points in order to understand the alterations in their concentration peaks. Recent studies have revealed that the pollen concentration peaks in mountain snow covers in temperate regions are useful for distinguishing between annual and several seasonal layers. Moreover, a dating method was applicable to a melting ice core. However, the manner in which pollen grains and their concentration peak values get influenced by melt water needs to be clarified. The present study intends to clarify this issue. Snow samples were collected from the Norikura Highland in central Japan during two snow-melting seasons: (1) from March to April in 2005 and (2) from March to May in 2006. The analysis of the C. japonica pollens was carried out because the pollen release reaches a high level from March to April in Japan when the winter seasonal snow still remains at the site; further, the pollen grains are commonly found within a typical size range. The results showed that the snow depth from the ground surface decreased because of snow melting during April and May, and the pollen concentration peak was consistently observed at the surface of the snow cover during the melting process. This indicated that the pollen concentration peak was not redistributed to the lower layers because of melting and the pollen grains present in the melted snow were concentrated at the surface. However, when the snow cover was about to disappear, the peak value decreased. This might account for the horizontal relocation of the pollen grains at the surface. Additionally, the peaks persisted at the surface even in the regions of the snow cover where water channels were formed. This indicated that the pollen peaks in the snow cover did not move toward the lower layers because of significant melting, although the peak values themselves may be changed due to the horizontal relocation of pollen grains.ArticleBulletin of Glaciological Research. 25:1-7 (2008)journal articl

Recent spatial distribution of Tritium concentration in surface snow over East Antarctica

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc

Spatial variation of surface mass balance and seasonal variation of dust deposition at EGRIP, Greenland

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / Entrance Hall (1st floor) , National Institute of Polar Researc

Atmospheric sea-salt and halogen chemistry in the Antarctic region

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc

Perfluorooctane Sulfonate (PFOS) and Related Perfluorinated Compounds in Human Maternal and Cord Blood Samples: Assessment of PFOS Exposure in a Susceptible Population during Pregnancy

Fluorinated organic compounds (FOCs), such as perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorooctane sulfonylamide (PFOSA), are widely used in the manufacture of plastic, electronics, textile, and construction material in the apparel, leather, and upholstery industries. FOCs have been detected in human blood samples. Studies have indicated that FOCs may be detrimental to rodent development possibly by affecting thyroid hormone levels. In the present study, we determined the concentrations of FOCs in maternal and cord blood samples. Pregnant women 17–37 years of age were enrolled as subjects. FOCs in 15 pairs of maternal and cord blood samples were analyzed by liquid chromatography–electrospray mass spectrometry coupled with online extraction. The limits of quantification of PFOS, PFOA, and PFOSA in human plasma or serum were 0.5, 0.5, and 1.0 ng/mL, respectively. The method enables the precise determination of FOCs and can be applied to the detection of FOCs in human blood samples for monitoring human exposure. PFOS concentrations in maternal samples ranged from 4.9 to 17.6 ng/mL, whereas those in fetal samples ranged from 1.6 to 5.3 ng/mL. In contrast, PFOSA was not detected in fetal or maternal samples, whereas PFOA was detected only in maternal samples (range, < 0.5 to 2.3 ng/mL, 4 of 15). Our results revealed a high correlation between PFOS concentrations in maternal and cord blood (r(2) = 0.876). However, we did not find any significant correlations between PFOS concentration in maternal and cord blood samples and age bracket, birth weight, or levels of thyroid-stimulating hormone or free thyroxine. Our study revealed that human fetuses in Japan may be exposed to relatively high levels of FOCs. Further investigation is required to determine the postnatal effects of fetal exposure to FOCs

Seasonal variations of snow chemistry at EGRIP, Greenland

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc

A rare benign genitourinary tumor in a Japanese male: urinary retention owing to aggressive angiomyxoma of the prostate

Close examination of a 67-year-old Japanese man, who complained of persistent nocturia, revealed that a semitransparent polypoid tumor had developed from the bladder neck to the prostatic urethra obstructing the internal urethral meatus, which resulted in excessive urinary retention and post-renal dysfunction. The tumor was resected by a transurethral procedure and a pathological examination of specimens revealed aggressive angiomyxoma (AAM) of the prostate. AAM usually develops in the intrapelvic and perineal organs of females. So far as we know, this is the second case of primary prostatic AAM reported in the English literature, and is the first case where the patient encountered urethral obstruction

Location, morphology and size distribution of solid particles in an ice core retrieved from NEEM, Greenland

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc