Reduced marine biogenic sulphate flux in East Antarctica during glacial periods - Based on ion chemistry records from Dome Fuji ice core -

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / 2F Auditorium, National Institute of Polar Researc

Glacial-cycle scale variability of dust flux during the past 720 k-years in the Dome Fuji ice core, Antarctica

第2回極域科学シンポジウム　氷床コアセッション 11月16日（水） 国立極地研究所 2階大会議室前フロ

Chemical Compounds of Water-Soluble Impurities in Dome Fuji Ice Core

The amounts of water-soluble impurities in ice cores have been widely discussed in past research on prehistoric climates; in those studies, the analysis of the soluble-aerosol signals of several ion concentrations took place after the ice cores were melted. However, the chemical compounds of the impurities being studied were unclear, due to the ionization of the impurities being caused by the melting of the ice cores. In this paper, the chemical compounds of water-soluble impurities in Dome Fuji ice core are discussed and analyzed using micro-Raman spectroscopy and ion chromatography. Raman spectroscopy helped identify micro-inclusions within ice grains as water-soluble impurities made up primarily of sodium sulfate formed in warm periods and calcium sulfate in cold periods. The major chemical compounds of the water-soluble impurities (sodium sulfate and calcium sulfate) were deduced by examining ion concentrations and the stability of chemical compounds. The amounts of impurities reflect the differences in climatic time periods, as the environment was acidic during warm times and reductive during cold.IV. Chemical properties and isotope

The chemical forms of water-soluble microparticles preserved in the Antarctic ice sheet during Termination I

This study clarifies changes in the chemical forms of microparticles during Termination I, the period of drastic climate change between the Last Glacial Maximum (LGM) and the Holocene. We determine the chemical forms of individual water-soluble microparticles through micro-Raman spectroscopy and compare the relative frequencies of different types with the ion concentrations in melted ice. Micro-Raman spectroscopy shows that Na2SO4・10H2O and MgSO4・11H2O are abundant in Holocene ice, while CaSO4・2H2O and other salts are abundant in LGM ice. Further, the number of CaSO4・2H2O particles is strongly correlated with the concentration of Ca2+ during Termination I. Taken together, the evidence strongly suggests that most of the Ca2+ exists as CaSO4・2H2O. The different compositions of microparticles from the Holocene and LGM can be explained by ion balance arguments

A Technique for Measuring Microparticles in Polar Ice Using Micro-Raman Spectroscopy

We describe in detail our method of measuring the chemical forms of microparticles in polar ice samples through micro-Raman spectroscopy. The method is intended for solid ice samples, an important point because melting the ice can result in dissociation, contamination, and chemical reactions prior to or during a measurement. We demonstrate the technique of measuring the chemical forms of these microparticles and show that the reference spectra of those salts expected to be common in polar ice are unambiguously detected. From our measurements, Raman intensity of sulfate salts is relatively higher than insoluble dust due to the specific Raman scattering cross-section of chemical forms of microparticles in ice

Influence of Restrictive Ventilation Impairment on Physical Function and Activities of Homebound Elderly Persons

Background: Examinations of respiratory function and respiratory muscle strength are evaluation methods for stamina factors, but instantaneous ability evaluation is disproportionately emphasized in evaluations of elderly persons. Methods: The participants were 290 persons who were capable of undergoing respiratory examinations. The participants were firstly divided into two groups; 42 persons in a normal group (percentage of forced vital capacity ≥80%) and 42 patients in a restrictive group (percentage of forced vital capacity <80%). The participants were then subcategorized into three groups; 21 participants were randomly selected from the normal group (normal-1), 20 regularly exercising restrictive participants were assigned to a restrictive training group (RTG), and 22 participants who did not exercise were assigned to a restrictive nontraining group (RNTG). The measured parameters were respiratory function, cognitive function, spinal alignment, muscle strength, skeletal muscle volume, gait evaluation, subjective feelings of life, and active ability. Results: Six-minute walk test was significantly lower in the restrictive group compared with the normal group (p<0.05). Walking time of the 10-m obstruction course in the normal-1 group differed significantly from the RTG (p<0.05) and RNTG (p<0.01). Highest walking speed, Timed Up and Go test, and 6-minute walk test did not significantly differ between the normal-1 group and RTG, but significant differences were observed between the normal-1 group and RNTG (p<0.01, p<0.05, and p<0.05, respectively). Conclusions: Although patients with restrictive ventilation impairment were unlikely to be aware of their disorder, degradation in systemic stamina had already commenced. It appears that maintaining exercise habits prevented degradation of not only instantaneous walking ability but also of systemic stamina