著者

Naṣīr al-Din al-Ṭūsī a critical edition translated and introduced by Daniel L. Newman

出版者

Saqi

巻号頁・発行日

2014

著者

Yuki Hara Kenta Adachi Shunsuke Kagohashi Kazuo Yamagata Hideyuki Tanabe Shinji Kikuchi Sei-Ichi Okumura Akatsuki Kimura

出版者

THE SOCIETY OF CHROMOSOME RESEARCH

雑誌

Chromosome Science (ISSN:13441051)

巻号頁・発行日

vol.19, no.1-4, pp.43-49, 2016 (Released:2017-06-26)

参考文献数

22

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Across species, eukaryotic chromosomes share common features at the molecular level. However, common features at the cellular level are not well investigated. A correlation has been suggested between the linear packing ratio of mitotic chromosomes and the intra-nuclear DNA density, by comparing these values in the nematode Caenorhabditis elegans. In this study, these values were measured and compared among several metazoan and plant species. The obtained values corroborated the correlation proposed in the previous study, supporting the theory that intra-nuclear DNA density is a common regulator of chromosome condensation. Moreover, the comparison among different species suggested a correlation between the length of a mitotic chromosome and the nuclear volume to the power of 2/3. Given this observation, we speculate that: (i) a rate-limiting component defines the length of a mitotic chromosome that is proportional to the nuclear surface area, and (ii) such regulation of the mitotic chromosomal length may play a role in maintaining the ratio between the cell size and the metaphase plate.

著者

橋本 健一 Ken-ichi HASHIMOTO 千葉県立衛生短期大学(生物学) Chiba College of Health Science

雑誌

千葉県立衛生短期大学紀要 = Bulletin of Chiba College of Health Science (ISSN:02885034)

巻号頁・発行日

vol.13, no.2, pp.3-9, 1994

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In the velvet swallowtail butterfly, Papilio bianor dehaanii, there is a seasonal morph such as the spring-and summer-forms. When larvae were reared under a short photoperiod (less than LD 8 : 16hr.), all of them entered into pupal diapause and subsequently developed into small adults of the spring-form. On the other hand, under a long one (under room conditions), they all averted diapause and developed into large summer-form adults. The front wing length and size of the pupae were significantly different between diapause and non-diapause groups. It thus appears that a seasonal morph reflected in the size was deter-mined simultaneously by photoperiod during the larval period. When diapausing pupae were kept under various periods of chilling at 4℃, the longer the chilling brought the earlier onset of adult emergence and a narrower range of emergence. A well synchronized emergence from diapausing pupae was brought about by chilling for 140 days. In the Japanese swallowtail butterfly, Papilio xuthus, when larvae were reared under natural conditions in autumn, all of them entered into the pupal diapause. Three groups of diapausing pupae, that had overwintered from late autumn under natural conditions, were transfered to 20℃ conditions on Jan. 14, Mar. 2 and Apr. 4 respectively. In most of the diapausing pupae which had been transfered on Mar. 2 or Apr. 4, adult emergence occured within 20 days after the onset of incubation at 20℃. It thus seems that pupal diapause of them had terminated during their overwintering period.

著者

橋本 健一 Ken-ichi HASHIMOTO 千葉県立衛生短期大学

雑誌

千葉県立衛生短期大学紀要 = Bulletin of Chiba College of Health Science (ISSN:02885034)

巻号頁・発行日

vol.26, no.2, pp.1-7, 2008

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ナガサキアゲハPapilio memnon thunbergii SieboldおよびクロアゲハPapilio protenor demetrius Stollの千葉県鴨川市個体群(35°07'N)の20℃での蛹休眠誘起の臨界日長はナガサキアゲハでは約12時間40分,クロアゲハでは14時間以上であり,ナガサキアゲハの臨界日長は同所的に生息するクロアゲハより1時間以上短かった。ナガサキアゲハ鴨川市個体群の臨界日長は既に報告されている鹿児島市,和歌山市,箕面市,清水市および三浦市の各個体群での値(Yoshio and Ishii 1998, 2004)とほぼ同様であるので,本種は休眠性の変化を伴わずに北方へ分布を拡大しているものと思われる。このような分布の拡大は,秋季の気温の上昇により休眠世代の幼虫が蛹化に至るまでの温量が得られるようになったことが要因の1つであると考えられる。

著者

Young-Ran Yeun

出版者

理学療法科学学会

雑誌

Journal of Physical Therapy Science (ISSN:09155287)

巻号頁・発行日

vol.29, no.5, pp.936-940, 2017 (Released:2017-05-16)

参考文献数

12

被引用文献数

8

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[Purpose] This study performed an effect-size analysis of massage therapy for shoulder pain. [Subjects and Methods] The database search was conducted using PubMed, CINAHL, Embase, PsycINFO, RISS, NDSL, NANET, DBpia, and KoreaMed. The meta-analysis was based on 15 studies, covering a total of 635 participants, and used a random effects model. [Results] The effect size estimate showed that massage therapy had a significant effect on reducing shoulder pain for short-term efficacy (SMD: −1.08, 95% CI: −1.51 to −0.65) and for long-term efficacy (SMD: −0.47, 95% CI: −0.71 to −0.23). [Conclusion] The findings from this review suggest that massage therapy is effective at improving shoulder pain. However, further research is needed, especially a randomized controlled trial design or a large sample size, to provide evidence-based recommendations.

著者

Bernard Pignon Marie-Antoinette Sevestre Lukshe Kanagaratnam Gilles Pernod Dominique Stephan Joseph Emmerich Claude Clement Gabrielle Sarlon Carine Boulon Claire Tournois Philippe Nguyen

出版者

日本循環器学会

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-17-0045, (Released:2017-06-10)

参考文献数

47

被引用文献数

35

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Background:Cell therapy is a therapeutic option for patients presenting with nonrevascularizable critical limb ischemia (CLI). However there is a lack of firm evidence on its efficacy because of the paucity of randomized controlled trials.Methods and Results:The BALI trial was a multicenter, randomized, controlled, double-blind clinical trial that included 38 patients. For all of them, 500 mL of bone marrow were collected for preparation of a BM-MNC product that was implanted in patients assigned to active treatment. For the placebo group, a placebo cell-free product was implanted. Within 6 months after inclusion, major amputations had to be performed in 5 of the 19 placebo-treated patients and in 3 of the 17 BM-MNC-treated patients. According to a classical logistic regression analysis there was no significant difference. However, when using the jackknife analysis, 6 months after inclusion BM-MNC implantation was associated with a lower risk of major amputation (odds ratio (OR): 0.55; 95% confidence interval (CI): 0.52–0.58; P<0.0001) and of occurrence of any event (major or minor amputation, or revascularization) (OR: 0.30; 95% CI: 0.29–0.31; P<0.0001). The secondary endpoints (i.e., pain, ulcers, TcPO2, and ankle-brachial index value) were not statistically different between groups.Conclusions:Our results suggested that cell therapy reduced the risk of major amputation in patients presenting with nonrevascularizable CLI.

著者

Hayato Tada Masa-aki Kawashiri Masakazu Yamagishi

出版者

日本循環器学会

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-17-0586, (Released:2017-07-01)

参考文献数

11

被引用文献数

1

著者

Masayoshi Yamamoto Yoshihiro Seo Tomoko Ishizu Isao Nishi Yoshie Hamada-Harimura Tomoko Machino-Ohtsuka Kimi Sato Seika Sai Akinori Sugano Kenichi Obara Kazutaka Aonuma

出版者

日本循環器学会

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-17-0240, (Released:2017-06-06)

参考文献数

27

被引用文献数

9

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Background:Although experimental animal studies report many pleiotropic effects of dipeptidyl peptidase-4 inhibitors (DPP-4i), their prognostic value has not been demonstrated in clinical trials.Methods and Results:Among 838 prospectively enrolled heart failure (HF) patients hospitalized for acute decompensated HF, 79 treated with DPP-4i were compared with 79 propensity score-matched non-DPP-4i diabetes mellitus (DM) patients. The primary endpoint was all-cause mortality; the secondary endpoint was a composite of cardiovascular death and hospitalization. During follow-up (423±260 days), 8 patients (10.1%) in the DPP-4i group and 13 (16.5%) in the non-DPP-4i group died (log-rank, P=0.283). The DPP-4i group did not have a significantly higher rate of all-cause mortality (log-rank, P=0.283), or cardiovascular death or hospitalization (log-rank, P=0.425). In a subgroup analysis of HF with preserved ejection fraction (HFpEF; n=75), the DPP-4i group had a significantly better prognosis than the non-DPP-4i group regarding the primary endpoint (log-rank, P=0.021) and a tendency to have better prognosis regarding the secondary endpoint (log-rank, P=0.119). In patients with HF with reduced EF (n=83), DPP-4i did not result in better prognosis.Conclusions:DPP-4i did not increase the risk of adverse clinical outcomes in patients with DM and HF. DPP-4i may be beneficial in HFpEF.

著者

Yun-Shan Li Ming-Fen Song Hiroshi Kasai Kazuaki Kawai

出版者

日本環境変異原学会

雑誌

Genes and Environment (ISSN:18807046)

巻号頁・発行日

vol.35, no.3, pp.88-92, 2013 (Released:2013-09-03)

参考文献数

16

被引用文献数

1 10

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Human epidemiological studies have revealed significant increases in the cancer incidence rates by exposure to 100 mSv or higher doses of ionizing radiation. However, the relationship between lower doses of ionizing radiation and cancer incidence is still unclear. In general, oxidative DNA damage is closely related to cancer generation. We studied the oxidative DNA damage elicited by low dose ionizing irradiation. The γ-ray irradiation of a deoxyguanosine solution caused a linear increase in the 8-hydroxydeoxyguanosine (8-OHdG) levels, in the range of 20-300 mGy. Thus, 8-OHdG seems to be a good marker of the oxidative DNA damage caused by ionizing radiation. In contrast, in the case of the whole body X-ray irradiation of mice, the 8-OHdG levels in liver DNA and urine increased from about 500 and 200 mGy, respectively. These results indicate that living organisms have a defense mechanism against the oxidative damage caused by ionizing radiation. Considering the 8-OHdG levels as an ionizing radiation effect marker for living organisms, a threshold level of irradiation seems to exist for oxidative damage and tumorigenesis. Furthermore, diet imbalances increased radiation damage. Lifestyle may affect the radiation hazard.

著者

François Desmeules Jennifer Boudreault Clermont E. Dionne Pierre Frémont Véronique Lowry Joy C. MacDermid Jean-Sébastien Roy

出版者

(公社)日本産業衛生学会

雑誌

Journal of Occupational Health (ISSN:13419145)

巻号頁・発行日

vol.58, no.5, pp.389-403, 2016-09-20 (Released:2016-09-30)

参考文献数

43

被引用文献数

59

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Objective: To perform a systematic review of randomized controlled trials (RCTs) on the efficacy of therapeutic exercises for workers suffering from rotator cuff (RC) tendinopathy. Methods: A literature search in four bibliographical databases (Pubmed, CINAHL, EMBASE, and PEDro) was conducted from inception up to February 2015. RCTs were included if participants were workers suffering from RC tendinopathy, the outcome measures included work-related outcomes, and at least one of the interventions under study included exercises. The methodological quality of the studies was evaluated with the Cochrane Risk of Bias Assessment tool. Results: The mean methodological score of the ten included studies was 54.4%±17.2%. Types of workers included were often not defined, and work-related outcome measures were heterogeneous and often not validated. Three RCTs of moderate methodological quality concluded that exercises were superior to a placebo or no intervention in terms of function and return-to-work outcomes. No significant difference was found between surgery and exercises based on the results of two studies of low to moderate methodological quality. One study of low methodological quality, comparing a workplace-based exercise program focusing on the participants' work demands to an exercise program delivered in a clinical setting, concluded that the work-based intervention was superior in terms of function and return-to-work outcomes. Conclusion: There is low to moderate-grade evidence that therapeutic exercises provided in a clinical setting are an effective modality to treat workers suffering from RC tendinopathy and to promote return-to-work. Further high quality studies comparing different rehabilitation programs including exercises in different settings with defined workers populations are needed to draw firm conclusions on the optimal program to treat workers.

著者

Mafumi Owa Kazunori Aizawa Nobuyuki Urasawa Hiroyuki Ichinose Kazuya Yamamoto Koji Karasawa Mitsuru Kagoshima Jun Koyama Shu-ichi Ikeda

出版者

日本循環器学会

雑誌

JAPANESE CIRCULATION JOURNAL (ISSN:00471828)

巻号頁・発行日

vol.65, no.4, pp.349-352, 2001 (Released:2001-06-01)

参考文献数

13

被引用文献数

66 105

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Four patients had the clinical features of `ampulla cardiomyopathy', consisting of acute-onset transient left ventricular apical akinesis with basal normokinesis, normal coronary angiogram, ST-segment elevation and subsequent giant T wave inversion, which mimicked acute coronary syndrome, the onset of which occurred shortly after extreme mental stress. Myocardial necrosis was minimal, although 2 patients showed elevated serum catecholamine levels in the acute phase. Each patient underwent serial cardiac radionuclide single-photon emission computed tomography of myocardial functional sympathetic innervation, fatty acid metabolism and perfusion using I-123-metaiodobenzyl-guanidine (MIBG), I-123-β-metyl-iodophenyl pentadecanoic acid (BMIPP) and thallium-201 (201Tl), respectively. In the acute phase, MIBG and BMIPP imaging showed an uptake defect in the apical region, whereas 201Tl uptake was mildly decreased. When assessed semi-quantitatively, the MIBG images had higher defect scores from the acute phase throughout the year of observation compared with BMIPP, and 201Tl. These observations suggest that the primary cause of ampulla cardiomyopathy is related to a disturbance of the cardiac sympathetic innervation. (Jpn Circ J 2001; 65: 349 - 352)

著者

Amari Shun-ichi

出版者

物性研究刊行会

雑誌

物性研究 (ISSN:07272997)

巻号頁・発行日

vol.70, no.3, pp.426-432, 1998-06-20

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この論文は国立情報学研究所の電子図書館事業により電子化されました。

著者

Jong-Ho Koh Kyung-Mi Kim Jin-Man Kim Jae-Chul Song Hyung-Joo Suh

出版者

公益社団法人日本薬学会

雑誌

Biological and Pharmaceutical Bulletin (ISSN:09186158)

巻号頁・発行日

vol.26, no.5, pp.691-694, 2003 (Released:2003-05-01)

参考文献数

24

被引用文献数

29 54

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This study was conducted to investigate the chemical component of the hot water (HW) fraction of mycelia of Cordyceps sinensis and its antifatigue and antistress effect against a stimulus in vivo using rats and mice. The growth of mycelia reached a maximum level of 31.6 g/l after 120 h of incubation. The main chemical composition of the HW fraction of mycelia of C. sinensis was found to be carbohydrate (78.9%) with 5% moisture. The swimming endurance capacity of mice orally administered with the HW fraction (150 and 300 mg/kg/d, respectively) was significantly prolonged from 75 to 90 min with a lessening of fatigue. When the HW fraction (150 mg/kg/d) was given to rats for 8 d including a 48 h stress period, the weight changes of the adrenal gland, spleen, thymus, and thyroid, which is an index of stress, were suppressed. The HW fraction also significantly inhibited the increase in total cholesterol and the decrease in alkaline phosphatase levels as biochemical parameters of immobilization stress in rats.

著者

Yuko Wada Yukie Takaoka Mitsuru Nozawa Miho Goto Ken-ichi Shimokawa Fumiyoshi Ishii

出版者

バイオ&ソーシャル・サイエンス推進国際研究交流会

雑誌

Drug Discoveries & Therapeutics (ISSN:18817831)

巻号頁・発行日

pp.2016.01053, (Released:2016-10-04)

参考文献数

16

被引用文献数

6

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We measured the pH, water-vapor permeability, adhesive force, peeling-force, elongation rate, support flexibility, and peeling time of medicinal and over-the-counter (OTC) tape preparations containing felbinac. When measuring the pH of each preparation, Felnabion (pH 4.5) was weakly acidic, and EMEC and Tokuon (pH 7.0) were neutral. When measuring the water-vapor permeability of each preparation, that of a generic product, EMEC (380 g/m2/24h), was twice as high as that of a brand-name product, Seltouch (189 g/m2/24 h). The adhesive force was measured using the ball tack test. The adhesive forces of OTC drugs, Salomethyl, Homepass, and Tokuhon (1.04 g), were higher than that of Seltouch (0.06 g). Concerning peeling-force measurement, the peeling-forces of a generic product, Falzy (4.15 N), and an OTC drug, Omuneed (4.89 N), were higher than that of Seltouch (0.91 N). The elongation rates of a generic product, Sumilu (319%), and OTC drugs, Nabolin (298%) and Homepass (299%), were higher than that of Seltouch (251%), but that of Tokuhon (72%) was lower. The support flexibilities of EMEC (150 degrees) and Tokuhon (131 degrees) were higher than that of Seltouch (96 degrees). In addition, the peeling time of Seltouch was 120 min or more, whereas those of EMEC and Nabolin were 1.4 and 0.2 min, respectively. These results suggest that the differences in pharmaceutical properties, such as the pH, water-vapor permeability, adhesive force, peeling-force, elongation rate, support flexibility, and peeling time, among the preparations markedly influence patients' subjective comfortableness. The results of this study facilitated individuals’ comfortableness-matched drug selection.

著者

Shigeatsu Hashimoto Masato Nagai Shingo Fukuma Tetsuya Ohira Mitsuaki Hosoya Seiji Yasumura Hiroaki Satoh Hitoshi Suzuki Akira Sakai Akira Ohtsuru Yukihiko Kawasaki Atsushi Takahashi Kotaro Ozasa Gen Kobashi Kenji Kamiya Shunichi Yamashita Shun-ichi Fukuhara Hitoshi Ohto Masafumi Abe the Fukushima Health Management Survey Group

出版者

一般社団法人 日本動脈硬化学会

雑誌

Journal of Atherosclerosis and Thrombosis (ISSN:13403478)

巻号頁・発行日

pp.35824, (Released:2016-09-13)

参考文献数

50

被引用文献数

44

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Aim: After the Great East Japan Earthquake, over 160,000 residents near the Fukushima Daiichi Nuclear Power Plant were forced to evacuate due to a nuclear accident. Health problems in these evacuees have since become major issues. We examined the association between evacuation and incidence of metabolic syndrome (METS) among residents in Fukushima.Methods: We conducted a cohort study among residents aged 40-74 years without METS at the time of the disaster in Fukushima. Among 20,269 residents who met the inclusion criteria before the disaster, 8,547 residents (3,697 men and 4,850 women; follow-up proportion: 42.2%) remained available for follow-up examinations after the disaster by the end of March 2013. The main outcome was incidence of METS, defined by guidelines from the Japanese committee, using data from the Comprehensive Health Check before and after the disaster. We divided participants by evacuation status and compared outcomes between groups. Using a logistic regression model, we estimated the odds ratio for incidence of METS, adjusting for potential confounders, age, gender, waist circumference, exercise habit, and alcohol consumption.Results: Incidence of METS was higher in evacuees (men 19.2%, women 6.6%) than in non-evacuees (men 11.0%, women 4.6%). Evacuees had higher body mass index, waist circumference, triglycerides, and fasting plasma glucose after the disaster than non-evacuees. We found a significant association between evacuation and incidence of METS (adjusted odds ratio 1.72, 95% confidence interval; 1.46-2.02).Conclusion: This is the first study to demonstrate that evacuation after a disaster is associated with increased incidence of METS.

著者

Franck Dumeignil Mickaël Capron Benjamin Katryniok Robert Wojcieszak Axel Löfberg Jean-Sébastien Girardon Simon Desset Marcia Araque-Marin Louise Jalowiecki-Duhamel Sébastien Paul

出版者

公益社団法人 石油学会

雑誌

Journal of the Japan Petroleum Institute (ISSN:13468804)

巻号頁・発行日

vol.58, no.5, pp.257-273, 2015-09-01 (Released:2015-11-01)

参考文献数

189

被引用文献数

2 28

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Biomass valorization is a booming field. Especially, the valorization of platform molecules by catalytic processes has driven a large interest in the recent years, and many groups are actively working on the transformation of biosourced substrates to a variety of upgraded chemicals. In this context, in the present paper we put in perspectives the scientific works of our research team. We first classified catalytic transformations of industrial interest according to the number of carbons of the starting material, from C1 to C6. They involve, among others, acid catalysts (e.g., for glycerol dehydration), redox catalysts (e.g., for 5-HMF conversion to diformylfuran), acid and redox catalysts (e.g., for direct acetalization of alcohols), or complex multifunctional catalysts, especially for the Guerbet reaction. Further, we also developed what we called ‘toolboxes,’ which are general concepts or technologies with a broader field of applications. For example, we adapted the two zones fluidized bed reactor (TZFBR) concept to the single reactor continuous regeneration of coking catalysts. Further, we designed a completely new high throughput platform enabling synthetizing, characterizing and testing the performances of many catalysts for considerably accelerating the catalysts discovery/optimization loop.

著者

Demián García Violini Ricardo S. Sánchez-Peña Ariel Velis Carlos Posse

出版者

一般社団法人 日本音響学会

雑誌

Acoustical Science and Technology (ISSN:13463969)

巻号頁・発行日

vol.37, no.1, pp.21-29, 2016-01-01 (Released:2016-01-01)

参考文献数

31

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In this work, three experiments are conducted. In a realistic environment (freeway), a database for the noise dynamics versus velocity in a motorcycle helmet is computed. Next, under the controlled conditions of an anechoic chamber, the models for the feedback (FB) and feedforward (FF) paths in the helmet are obtained by a filtering and identification process. Finally, in the same chamber, a hybrid (FB+FF) robust controller is tested against the actual noise measured in the freeway, and it achieves attenuations between 20 and 30 dB.

著者

Soo-Young CHOI Yu-Mi SONG Young-Won LEE Ho-Jung CHOI

出版者

公益社団法人 日本獣医学会

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.15-0695, (Released:2016-07-14)

被引用文献数

9

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Persistent left cranial vena cava (PLCVC) is an uncommon congenital thoracic venous anomaly in dogs. This study examines the clinical and CT findings of dogs diagnosed with PLCVC incidentally. In this study, complete type of PLCVC was diagnosed in 26 dogs with CT angiography. Shih tzu (17 cases) and Pekingese dogs (3 cases) were overrepresented. There was no gender predisposition, and the average age at presentation was 10.3 years. Of 26 dogs, one dog had a bridging vein connecting right and left cranial vena cavae, and another dog showed azygos vein terminating PLCVC. On the thoracic CT images in the third dog, the right cranial vena cava was absent so that right brachiocephalic vein ended to PLCVC. However, the right costocervical vein drained another vein coursing caudally to the right atrium with azygos vein. In conclusion, CT angiography is a very useful method to diagnose PLCVC and variations of related thoracic vein anomalies in dogs.

著者

Joo-Hyun Lee In-Gyu Yoo

出版者

理学療法科学学会

雑誌

Journal of Physical Therapy Science (ISSN:09155287)

巻号頁・発行日

vol.28, no.5, pp.1493-1495, 2016 (Released:2016-05-31)

参考文献数

19

被引用文献数

1

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[Purpose] The purpose of this study was to investigate the effects of the thickness of a wheelchair backrest provided for support and comfort on upper arm and trunk muscle load during wheelchair propulsion by using accelerometers. [Subjects and Methods] The Fourteen healthy participants were enrolled in this study. The study compared effects of three backrest conditions including no pad, a 3-cm-thick lumbar pad, and a 6-cm-thick lumbar pad. The instruments used for measurement were used two accelerometers. The participants were asked to propel their wheelchairs, which had been equipped with two accelerometers, 30 times. [Results] The intensity of muscle movement with the 3-cm-thick lumbar pad was significantly lower than the intensities with no lumbar pad and the 6-cm-thick lumbar pad. The muscle intensity did not differ significantly between the no pad and 6-cm-thick lumbar pad conditions. [Conclusion] An appropriately thick backrest has good effects on upper arm and trunk muscles during wheelchair propulsion. In the future, we must consider the appropriate backrest thickness for providing wheelchair users with a comfortable wheelchair.

著者

Vilma Ratia Kati Valtonen Anu Kemppainen Veli-Tapani Kuokkala

出版者

(社)日本トライボロジー学会

雑誌

Tribology Online (ISSN:18812198)

巻号頁・発行日

vol.11, no.2, pp.410-416, 2016-04-30 (Released:2016-04-30)

参考文献数

10

被引用文献数

7

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The role of edge wear was studied in impact-abrasion testing conditions with an impeller-tumbler type test device. Three steels with different mechanical properties were tested at 30° and 90° sample angles using natural granite stone as abrasive particles. The edge and planar (inner) areas were carefully exposed to the same conditions by using tightly fitted two-part samples to obtain relevant information about the differences in their wear behavior. The role of edge-concentrated wear was dominant in all materials, and the edge wear rate was several times higher than the wear rate of the inner parts of the specimens. The difference in wear rate was particularly large in short tests and with the 90° sample angle. However, the dominance of the edge-concentrated wear decreased as the test duration became longer. The wear mechanism was largely microfatigue in all materials, but the samples tested at the 30° sample angle showed more microcutting in comparison to the 90° samples. Moreover, the role of microcutting was higher in the wear of the edge parts than in the inner parts.