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論文(リポジトリ)

論文(リポジトリ)
Deng, Yange ; Fujinari, Hiroaki ; Yai, Hikari ; Shimada, Kojiro ; Miyazaki, Yuzo ; Tachibana, Eri ; Deshmukh, K. Dhananjay ; Kawamura, Kimitaka ; Nakayama, Tomoki ; Tatsuta, Shiori ; Cai, Mingfu ; Xu, Hanbing ; Li, Fei ; Tan, Haobo ; Ohata, Sho ; Kondo, Yutaka ; Takami, Akinori ; Hatakeyama, Shiro ; Mochida, Michihiro
出版情報: Atmospheric Chemistry and Physics.  22  pp.5515-5533,  2022-05-02.  European Geosciences Union — Copernicus Publications
URL: http://hdl.handle.net/20.500.12000/0002017926
概要: Filter-based offline analysis of atmospheric aerosol hygroscopicity coupled to composition analysis provides information complementary to that obtained from online analysis. However, its application itself and comparison to online analysis have remained limited to date. In this study, daily submicrometer aerosol particles (PM0.95, 50 % cutoff diameter 0.95 µm) were collected onto quartz fiber filters on Okinawa Island, a receptor of East Asian outflow, in the autumn of 2015. The chemical composition of water-soluble matter (WSM) in PM0.95, PM0.95 itself, and their respective hygroscopicities were characterized through the offline use of an aerosol mass spectrometer and a hygroscopicity tandem differential mobility analyzer. Thereafter, results were compared with those obtained from online analyses. Sulfate dominated the WSM mass (59 %), followed by water-soluble organic matter (WSOM, 20 %) and ammonium (13 %). WSOM accounted for most (91 %) of the mass of extracted organic matter (EOM) and the atomic O-to-C ratios (O : C) of WSOM and EOM were high (mean ± standard deviation were 0.84 ± 0.08 and 0.78 ± 0.08, respectively), both of which indicate highly aged characteristics of the observed aerosol. The hygroscopic growth curves showed clear hysteresis for most samples. At 85 % relative humidity (RH), the calculated hygroscopicity parameter κ values of the WSM (κWSM), WSOM, EOM, andPM0.95 (κPM0.95 ) were 0.50 ± 0.03, 0.22 ± 0.12, 0.20 ± 0.11, and 0.47 ± 0.03, respectively. An analysis using the thermodynamic Extended Aerosol Inorganics Model (E-AIM) shows, on average, that inorganic salts and WSOM contributed 88 % and 12 %, respectively, of the κWSM (or κPM0.95 ). High similarities were found between offline and online analysis for chemical compositions that are related to particle hygroscopicity (the mass fractions and O : C of organics and the degree of neutralization) and also for aerosol hygroscopicity. As possible factors governing the variation in κWSM, the influences of WSOM abundance and the neutralization of inorganic salts were assessed. At high RH (70 %–90 %), the hygroscopicity of WSM and PM0.95 was affected considerably by the presence of organic components; at low RH (20 %–50 %), the degree of neutralization could be important.This study not only characterized aerosol hygroscopicity at the receptor site of East Asian outflow but also shows that offline hygroscopicity analysis is an appropriate method, at least for aerosols of the studied type. The results encourage further applications to other environments and to more in-depth hygroscopicity analysis, in particular for organic fractions. 続きを見る
2.

論文(リポジトリ)

論文(リポジトリ)
Cai, Mingfu ; Tan, Haobo ; Chan, K. Chak ; Mochida, Michihiro ; Hatakeyama, Shiro ; Kondo, Yutaka ; Schurman, I. Misha ; Xu, Hanbing ; Li, Fei ; Shimada, Kojiro ; Li, Liu ; Deng, Yange ; Yai, Hikari ; Matsuki, Atsushi ; Qin, Yiming ; Zhao, Jun
出版情報: Aerosol and Air Quality Research.  17  pp.3194-3208,  2017-12.  Taiwan Association for Aerosol Research
URL: http://hdl.handle.net/20.500.12000/0002019360
概要: A suite of advanced instruments were employed to measure aerosol hygroscopicity, volatility and chemical composition at a suburban site in the Pearl River Delta (PRD) Region and at a marine site in Okinawa, respectively. The results showed that the particle number concentration in PRD is approximately ten times higher than that in Okinawa. Organics contributes about one half of the total NR-PM_1 concentration in PRD, while sulfate is the dominant component (about 60%) in Okinawa. Diurnal variation of the chemical species demonstrated that the site in PRD was affected by trafficrelated sources and industrial emissions, while the one in Okinawa is mainly affected by regional emissions. The V-TDMA measurements showed that a large fraction (20-45%) of particles in Okinawa volatilized at about 200°C and nearly all particles volatilized at about 300°C, indicating that the particles were almost volatile in Okinawa. In contrast, a fraction (15-21%) of particles in PRD did not evaporate even when heated to about 300°C, implying that these particles might contain black carbon or low-volatile organics. For 40-200 nm particles in Okinawa, the hygroscopicity parameter κ is around 0.5, significantly higher than that of PRD particles (κ ≈ 0.26). Particles tend to have bimodal distribution in PRD and unimodal in Okinawa, indicating that the former is externally mixed while the latter is internally mixed. 続きを見る
3.

論文(リポジトリ)

論文(リポジトリ)
Sekiguchi, Hiroshi ; Minei, Akira ; Noborikawa, Masako ; Kondo, Yutaka ; Tamaki, Yuichiro ; Fukuda, Tatsuma ; Hanashiro, Kazuhiko ; Kukita, Ichiro
出版情報: Respiratory physiology & neurobiology.  281  Elsevier
URL: http://hdl.handle.net/20.500.12000/50066
概要: The activity of the trapezius muscle is reportedly higher than that of other neck accessory muscles under a condition of increased inspiratory pressure in the standing position. The present study aimed to compare the activity of the trapezius muscle with those of the scalene and sternocleidomastoid muscles under a condition of increased inspiratory pressure in the supine position. This study included 40 subjects, and the muscle activity was measured using surface electromyography. Regarding the results, there was a significant difference in the muscle activity between the trapezius muscle and the scalene and sternocleidomastoid muscles (p = 0.003) in both men and women. Post-hoc analysis showed significant differences between trapezius and the other muscles. Moreover, there was no difference between the scalene and sternocleidomastoid muscles (p = 0.596). The increase in the change in electromyography activity of the muscle is greater in the trapezius muscle than in other muscles when the level of inspiratory pressure increases in the supine position.
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4.

論文(リポジトリ)

論文(リポジトリ)
Kondo, Yutaka ; Fukuda, Tatsuma ; Uchimido, Ryo ; Kashiura, Masahiro ; Kato, Soichiro ; Sekiguchi, Hiroshi ; Zamami, Yoshito ; Hifumi, Toru ; Hayashida, Kei
出版情報: Frontiers in Medicine.  8  Frontiers Media SA
URL: http://hdl.handle.net/20.500.12000/49985
概要: Background: Advanced Life Support (ALS) is regarded to be associated with improved survival in pre-hospital trauma care when compared to Basic Life Support (BLS) irrespective of lack of evidence. The aim of this study is to ascertain ALS improves survival for trauma in prehospital settings when compared to BLS.\nMethods: We searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for published controlled trials (CTs), and observational studies that were published until Aug 2017. The population of interest were adults (>18 years old) trauma patients who were transported by ground transportation and required resuscitation in prehospital settings. We compared outcomes between the ALS and BLS groups. The primary outcome was in-hospital mortality and secondary outcomes were neurological outcome and time spent on scene.\nResults: We identified 2,502 studies from various databases and 10 studies were included in the analysis (two CTs, and eight observational studies). The outcomes were not statistically significant between the ALS and BLS groups (pooled OR 1.14; 95% CI 0.95 to 1.36 for mortality, pooled OR 1.12; 95% CI 0.88 to 1.42 for good neurological outcomes, pooled mean difference −0.96; 95% CI−6.64 to 4.72 for on-scene time) in CTs. In observational studies, ALS prolonged on-scene time and increased mortality (pooled OR 1.56; 95% CI: 1.31 to 1.86 for mortality, and pooled mean difference, 1.26; 95% CI: 0.07 to 2.45 for on-scene time).
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