支援の輪はどのようにして形成されるのか?

Open House, ISM in Tachikawa, 2011.7.14統計数理研究所オープンハウス（立川）、H23.7.14ポスター発

[11C]Doxepin binding to histamine H1 receptors in living human brain: reproducibility during attentive waking and circadian rhythm

Molecular imaging in neuroscience is a new research field that enables visualization of the impact of molecular events on brain structure and function in humans. While magnetic resonance-based imaging techniques can provide complex information at the level of system, positron emission tomography (PET) enables determination of the distribution and density of receptor and enzyme in the human brain. Previous studies using [11C]raclopride and [11C]FLB457 revealed that the release of neuronal dopamine was increased in human brain by psychostimulants or reward stimuli. Following on from these previous [11C]raclopride studies, we examined whether the levels of neuronal release of histamine might change [11C]doxepin binding to the H1 receptors under the influence of physiological stimuli. The purpose of the present study was to evaluate the test–retest reliability of quantitative measurement of [11C]doxepin binding between morning and afternoon and between resting and attentive waking conditions in healthy human subjects. There was a trend for a decrease in [11C]doxepin binding during attentive calculation tasks compared with that in resting conditions, but the difference (less than 10%) was not significant. Similarly, the binding potential of [11C]doxepin in the cerebral cortex was slightly higher in the morning than that in the afternoon, but it was also insignificant. These data suggest that higher histamine release during wakefulness could not decrease the [11C]doxepin binding in the brain. This study confirmed the reproducibility and reliability of [11C]doxepin in the previous imaging studies to measure the H1 receptor

A Conversation Analysis Study of Speaking Rate Control by a Dysarthric Patient : A Case in which Dysarthria Improved in Conversation Continuity and Length of Utterances through Using a Pacing Board

ペーシングボードの使用により発話明瞭度が向上したdysarthria例に対して,会話分析の立場から「会話の伝達率」と「1発話の長さ」を検討し,主に以下の結果を得た.(1)ペーシングボード非使用時の会話伝達率は54.0%であったのに比し,使用時では98.1%と向上していた.(2)1発話の長さに関しては,モーラ数による比較ではペーシングボード非使用時の平均モーラ数は5.9,使用時は11.9であった.また平均文節数は非使用時1.4,使用時2.8と両指標とも約2倍に延長していた.以上の結果に基づいて,dysarthriaにおける発話速度調節訓練について会話分析から検討を加えた.Conversational transmissibility and length of utterances were studied in a　dysarthric patient who improved in intelligibility　because of use of a pacing board.The following results were obtained : (1)Conversational transmissibility was 54% when the pacing board was not used, whereas　transmissibility improved to 98.1 % when the board was used. (2) Comparison of the utterance length was made based on the number of mora, in which the average mora was 5.9 without use of the pacing board and 11.9 with use of the board. The number of average segments was 1.4 without　the board as opposed to 2.8 with the board. In both cases the indices increased by　nearly twofold when the pacing board was used. Based on these results, discussion　was held on the training of speaking rate control by the dysarthric speaker based on　conversation analysis

Reassessing the atmospheric oxidation mechanism of toluene

Photochemical oxidation of aromatic hydrocarbons leads to tropospheric ozone and secondary organic aerosol (SOA) formation, with profound implications for air quality, human health, and climate. Toluene is the most abundant aromatic compound under urban environments, but its detailed chemical oxidation mechanism remains uncertain. From combined laboratory experiments and quantum chemical calculations, we show a toluene oxidation mechanism that is different from the one adopted in current atmospheric models. Our experimental work indicates a larger-than-expected branching ratio for cresols, but a negligible formation of ring-opening products (e.g., methylglyoxal). Quantum chemical calculations also demonstrate that cresols are much more stable than their corresponding peroxy radicals, and, for the most favorable OH (ortho) addition, the pathway of H extraction by O_2 to form the cresol proceeds with a smaller barrier than O_2 addition to form the peroxy radical. Our results reveal that phenolic (rather than peroxy radical) formation represents the dominant pathway for toluene oxidation, highlighting the necessity to reassess its role in ozone and SOA formation in the atmosphere

Exploring indoor and outdoor dust as a potential tool for detection and monitoring of COVID-19 transmission

This study investigated the potential of using SARS-CoV-2 viral concentrations in dust as an additional surveillance tool for early detection and monitoring of COVID-19 transmission. Dust samples were collected from 8 public locations in 16 districts of Bangkok, Thailand, from June to August 2021. SARS-CoV-2 RNA concentrations in dust were quantified, and their correlation with community case incidence was assessed. Our findings revealed a positive correlation between viral concentrations detected in dust and the relative risk of COVID-19. The highest risk was observed with no delay (0-day lag), and this risk gradually decreased as the lag time increased. We observed an overall decline in viral concentrations in public places during lockdown, closely associated with reduced human mobility. The effective reproduction number for COVID-19 transmission remained above one throughout the study period, suggesting that transmission may persist in locations beyond public areas even after the lockdown measures were in place