Yasuo Shimizu

Dr. Yasuo Shimizu


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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TKTetsuhiro Kidokoro
Tetsuhiro Kidokoro
YSYasuo Shimizu
Yasuo Shimizu
KEKanako Edamoto
Kanako Edamoto
MAMichael Annear
Michael Annear
The purpose of the present study was to examine the effects of height-adjustable standing desks on time-series variation in sedentary behavior (SB) among primary school children. Thirty-eight children aged 11–12 years (22 boys and 16 girls) from two classes at a primary school in Nagano, Japan, participated in this study. One class was allocated as the intervention group and provided with individual standing desks for 6 months, and the other was allocated as the control group. Time spent in SB, light-intensity physical activity (LPA), and moderate-to-vigorous-intensity physical activity (MVPA) was measured using accelerometers (ActiGraph) at baseline and follow-up. Time spent in SB was significantly lower by 18.3 min/day on average in the intervention class at follow-up (interaction effects: F(1, 36) = 4.95, p = 0.035, η2 = 0.082). This was accompanied by a significant increase in time spent in MVPA (+19.9 min/day on average). Our time-series analysis showed significant decreases in SB during school time, while no change in SB was found during non-school time. This result indicates that the use of standing desks promotes an overall reduction in SB with no compensatory increase during non-school time.

MAMichael Annear
Michael Annear
YSYasuo Shimizu
Yasuo Shimizu
TKTetsuhiro Kidokoro
Tetsuhiro Kidokoro
Background and objectives: Health-related expectations regarding aging is a gerontological construct that is potentially predictive of morbidity and mortality in later life. The Expectations Regarding Ageing scale (ERA-12) is a widely used measure of health-related expectations, although it has not previously been administered in Japanese. The present research aimed to elucidate the psychometric properties of the first Japanese translation of the ERA-12 and evaluate health-related expectations among middle-aged and older Japanese. Research design and methods: Repeated online surveys were conducted with representative quota samples of middle-aged and older adults in Tokyo during 2021 (N = 1600). Primary outcome measures included total and subscale scores on a Japanese translation of the ERA-12 (ERA-12-J) addressing perceptions of physical, mental, and cognitive health. Standard measures were also used to gather information regarding respondent demographic details, general health, and health-related behavior. Results: The ERA-12-J and associated subscales showed acceptable test-retest reliability (t(1598) = 0.60, p = 0.63), internal consistency (α > 0.80), inter-item correlation (r = 0.21–0.78) and item-total correlation (r = 0.53–0.73). Confirmatory Factor Analysis verified the hypothesized three-factor structure and construct validity on four common indices of fit (GFI = 0.968; CFI = 0.978; AGFI = 0.950; RMSEA = 0.059). ERA-12-J scores among Japanese respondents revealed prevailing negative sentiments concerning physical and cognitive health, with less negative sentiment regarding mental health. Significant and independent differences emerged concerning gender and age cohort, with middle-aged adults and females holding more negative expectations about their future health. Discussion and implications: The ERA-12-J provides a sound basis for the elucidation of health-related expectations about aging in Japan and a useful tool for international comparative studies. Education and workplace intervention may be required in Japan to address age and gender disparities in health-related expectations.

13 December 2023 in Environments
Verified
Journal Article
Open access
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KTKanoko Takahashi
Kanoko Takahashi
RFRyosuke Fujinuma
Ryosuke Fujinuma
TYTomoyasu Yoshitomi
Tomoyasu Yoshitomi
YSYasuo Shimizu
Yasuo Shimizu
MKMakito Kobayashi
Makito Kobayashi
Various artificial materials and facilities are sources of microplastics, including artificial turf sports fields. In artificial turf fields, polyethylene fibers are attached to a basal cloth with adhesives. In the present study, we investigated whether the fibers in the field were detached from the basal cloth or torn in the field, and whether they moved to the surrounding ditches that were connected to sewage pipes. In the field, we collected fibers shorter in length compared to the original and these were free from basal cloth, indicating the tearing of the fibers due to players’ activities. We also collected fibers from the ditches, which indicated a migration of the fibers from the field into the ditches. These results suggest that the fibers in ditches could enter sewage treatment plants and be released into the aquatic environment as microplastics. We also examined whether goldfish, Carassius auratus, ingested these fibers, and observed that the fish ingested them with feed while the fish did not without feed. These results indicate that the fiber ingestion by the fish occurred unintentionally when they swallowed their feed. The present study demonstrated that artificial turf fibers in sports fields could turn into microplastics that can be ingested by wild fishes.

25 November 2025 in Microplastics
Verified
Journal Article
Open access
PDF file
SMSayaka Manabe
Sayaka Manabe
YSYasuo Shimizu
Yasuo Shimizu
TYTomoyasu Yoshitomi
Tomoyasu Yoshitomi
RFRyosuke Fujinuma
Ryosuke Fujinuma
MKMakito Kobayashi
Makito Kobayashi
The migration of terrestrial microplastics (MPs) into aquatic environments is considered to have negatively affected aquatic ecosystems. However, quantifying terrestrial pathways is challenging because of the diverse sources of MPs. A poorly understood MP source is shoe outsoles. Therefore, this study determined whether shoes released MPs by abrasion and conducted a series of five experiments to study the potential impacts on aquatic life. The first and second experiments examined the relationship between the distance walked or jogged and the weight loss of shoes. The weight of the shoes decreased significantly as the moving distance increased; however, the values did not differ significantly between walking and jogging. The third experiment tested the size and number of MPs originating from shoe outsole under simulated conditions using sandpaper, which imitated the surface of an asphaltic pavement. The number of MPs increased as the number of contacts with the sandpaper increased. The fourth and fifth experiments examined whether goldfish, Carassius auratus, ingested rubber tips (RTs) derived from the shoe outsoles. When goldfish were given sinking RT or floating RT, they ingested both types of RT with or without feed, suggesting that goldfish recognized RTs as feed. The results of this study suggested that shoes released abrasion debris and particles into the environment as MPs. This study is the first to demonstrate the process of MP release from shoe outsoles and the ingestion of MPs from shoe outsoles by fish.