著者

Ryojiro Minato Shigeru Tanaka

出版者

Japan Explosives Society

雑誌

Science and Technology of Energetic Materials (ISSN:13479466)

巻号頁・発行日

vol.83, no.4, pp.111-116, 2022 (Released:2022-09-09)

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The present study explores the explosion risk of nitromethane in fluid hammer phenomena. Nitromethane flowed through the flowpath by the gas-pressurized feed method in this test. The tank pressure conditions are 0.4, 0.6, 0.8 and 0.95 MPaG. No explosion occurred in any case in the present study. The fluid hammer test of water is also conducted to compare with nitromethane. The experimental peak pressure is 5.15 MPaG, and the fluid hammer pressure rise is 4.59 MPaG in the tank pressure condition of 0.95 MPaG. The experimental pressure rise of nitromethane is close to the theoretical prediction given by the Joukowsky equation in the flow velocity condition of more than 3.0 m・s-1 if the pressure propagation velocity is equal to the sonic speed. The peak pressure of the fluid hammer effect for water is the same with or higher than nitromethane. The other experimental fluid hammer test data indicates that nitromethane has similar fluid dynamic behaviors to water. Thus, the present investigation recommends using water for the fluid hammer test of the nitromethane feed system.

著者

Hiroto Hiyamuta Shigeru Tanaka Masatomo Taniguchi Masanori Tokumoto Kiichiro Fujisaki Toshiaki Nakano Kazuhiko Tsuruya Takanari Kitazono

出版者

Japan Atherosclerosis Society

雑誌

Journal of Atherosclerosis and Thrombosis (ISSN:13403478)

巻号頁・発行日

pp.49833, (Released:2019-08-22)

参考文献数

51

被引用文献数

19

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Aim: The incidence of sudden death and its risk factors in patients on hemodialysis remain unclear. This study aimed to clarify the incidence of sudden death and its risk factors in Japanese patients on hemodialysis. Methods: A total of 3505 patients on hemodialysis aged ≥ 18 years were followed for 10 years. Multivariate-adjusted hazard ratio (HR) with 95% confidence interval (95% CI) of each risk factor of sudden death were calculated using a Cox proportional hazards model. Results: During the 10-year follow-up, 1735 patients died, including 227 (13%) sudden deaths. The incidence rate of sudden death was 9.13 per 1000 person-years. In multivariable-adjusted Cox analysis, male sex (HR 1.67; 95% CI 1.20–2.33), age (HR 1.44; 95% CI 1.26–1.65 per 10-year higher), the presence of diabetes (HR 2.45; 95% CI 1.82–3.29), history of cardiovascular disease (HR 1.85; 95% CI 1.38–2.46), cardiothoracic ratio (HR 1.21; 95% CI 1.07–1.39 per 5% higher), serum C-reactive protein (HR 1.11; 95% CI 1.03–1.20 per 1-mg/dL higher), and serum phosphate (HR 1.15; 95% CI 1.03–1.30 per 1-mg/dL higher) were independent predictors of sudden death. A subgroup analysis stratified by sex or age showed that lower serum corrected calcium levels, not using vitamin D receptor activators in women, and a shorter dialysis session length in men or older people (≥ 65 years) increased the risk for sudden death. Conclusions: This study clarified the incidence of sudden death and its specific predictors in Japanese patients on hemodialysis.

著者

Masatoshi Hara Shigeru Tanaka Masatomo Taniguchi Kiichiro Fujisaki Kumiko Torisu Toshiaki Nakano Kazuhiko Tsuruya Takanari Kitazono

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

pp.4027-19, (Released:2020-02-12)

参考文献数

33

被引用文献数

3

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Objective Uremic toxins are known risk factors for cancer in patients undergoing hemodialysis (HD). Although adequate removal of uremic toxins might reduce the cancer risk by improving subclinical uremia, the relationship between the dialysis dose and risk of cancer death in patients undergoing HD remains unclear. Methods In this prospective observational study, 3,450 patients undergoing HD were followed up for 4 years. The primary outcome was cancer death. Patients were divided into quartiles according to their baseline Kt/V levels. The association between the Kt/V levels and risk of cancer death was estimated using the Kaplan-Meier method and Cox proportional-hazards model. Results A total of 111 patients (3.2%) died from cancer during the 4-year observational period. The 4-year survival rate decreased linearly with decreasing Kt/V. The multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer death were 2.23 (95% CI, 1.13-4.56), 1.77 (0.88-3.63), and 1.89 (1.04-3.56) in quartile (Q) 1, Q2, and Q3, respectively, compared with patients in the highest Kt/V category (Q4) (P for trend = 0.06). Every 0.1 increase in Kt/V was associated with a reduction of 8% in cancer death (HR 0.92, 95% CI 0.85-0.99). Conclusion A lower dialysis dose might be associated with a higher risk of cancer death in patients undergoing HD. Kt/V is a simple indicator of dialysis dose used in clinical practice and might be a useful modifiable factor for predicting the risk of cancer death. Further basic and interventional studies are needed to confirm the apparent reduction in cancer death associated with increasing the dialysis dose.

著者

Makiko Nakano Kazuyuki Omae Toru Takebayashi Shigeru Tanaka and Shigeki Koda

出版者

Japan Society for Occupational Health

雑誌

Journal of Occupational Health (ISSN:13419145)

巻号頁・発行日

pp.2017-0220-OA, (Released:2018-05-09)

被引用文献数

22

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Background: ortho-Toluidine (OT) was listed as a Group 1 carcinogen by the International Agency for Research on Cancer in 2012 based on epidemiological observations of workers co-exposed to OT and aromatic amines. From 2014 to 2017, several cases of bladder cancer (BCa) secondary to occupational exposure, primarily to OT, were detected in Japan.Objective: To describe 10 cases of BCa in male Japanese workers exposed primarily to OT at two plants that produce organic dye and pigment intermediates.Methods: Details of the 10 cases were obtained from company records and through a questionnaire and interview. The surrogate level of exposure to each aromatic amine was calculated as the total job-weight/month for each process for each job-year.Results: No quantitative exposure data were available. In most cases the surrogate level of exposure to OT was higher than to other amines. All 10 cases were exposed primarily to OT and co-exposed to para-toluidine, ortho-anisidine, aniline, 2,4-xylidine or ortho-chloroaniline. The age range at diagnosis was 41–71 years (mean 56). The duration of OT exposure was 7–28 years (mean 16.5). Disease latency was 16–28 years (mean 21.9). Eight patients were smokers. The main symptom at diagnosis was hematuria (70%).Conclusions: The characteristics of BCa cases were associated with a high surrogate level of OT exposure and a disease latency of more than 20 years from the initial OT exposure. The main route of OT exposure was likely through the skin. It is necessary to continue health examinations in these target groups.