Biomedical subjects

Masaharu Kumashiro

Publications and source records attributed to Masaharu Kumashiro.

7 recordsLinked to original sources

PubMed2006

Occupational low back pain among workers in some small-sized factories in Ardabil, Iran.

The main purpose of this study was to assess some of the individual and occupational risk factors contributing to induction or intensification of LBP among the employees suffering from this problem in four small size factories in Ardabil, Iran. This study was a cross-sectional study that was conducted among the personnel of four industrial companies. Interview, questionnaire survey, medical examination (Lasegue test), radiographic evaluation, and ergonomic survey (using the NIOSH checklist) were the methods to collect data. The result of the study was divided into two parts: individual factors and work-related factors. The highest frequency of low back pain was observed in the age of 30-34 years old, medium height and heavy weight with 34.4, 84.4, and 33.0 percent, respectively. With regard to work-related factors, load lifting with 44.7 and body posture with 18.4 percent contributed to low back pain as the most important occupational causes among the patients. Observing recommended regulations and limitations of load lifting, modifying and optimizing ergonomic conditions in the workplace, selecting workers with suitable body strength on the basis of a pre-employment examination and implementing a continuous educational program for employees were the most important methods recommended to prevent low back pain.

Adult↗

PubMed2006

Prevalence of respiratory symptoms among workers in industries of south Tehran, Iran.

OBJECTIVE: The aim of the present study was to determine the prevalence of respiratory symptoms from occupational lung hazards among workers in industries of south Tehran, IRAN. METHODOLOGY: This was a cross-sectional study in which by multistage random sampling items on demographic characteristics, cigarette smoking, occupational history and respiratory symptoms were collected of workers. RESULTS: The mean age of the workers was 38.5 (SD = 10.2) yr: age ranged from 19 to 70 yr. Of 880 workers under study, 252 (28.7%) were smoking. Also, it has been observed that workers exposed in the workplace with occupational chemical exposures such as dust, gas and fume pollutants. The prevalence of respiratory symptoms was cough (20.7%), phlegm (41.6%), dyspnea (41.7%), feel tightness (27.4%) and nose irritation (23.5%). CONCLUSIONS: Occupational exposures among workers in industries of south Tehran may cause respiratory symptoms and respiratory disorders, engineering controls and industrial hygiene is recommended.

Adult↗

PubMed2004

[Intermodal timing cues for audio-visual speech recognition].

The purpose of this study was to investigate the limitations of lip-reading advantages for Japanese young adults by desynchronizing visual and auditory information in speech. In the experiment, audio-visual speech stimuli were presented under the six test conditions: audio-alone, and audio-visually with either 0, 60, 120, 240 or 480 ms of audio delay. The stimuli were the video recordings of a face of a female Japanese speaking long and short Japanese sentences. The intelligibility of the audio-visual stimuli was measured as a function of audio delays in sixteen untrained young subjects. Speech intelligibility under the audio-delay condition of less than 120 ms was significantly better than that under the audio-alone condition. On the other hand, the delay of 120 ms corresponded to the mean mora duration measured for the audio stimuli. The results implied that audio delays of up to 120 ms would not disrupt lip-reading advantage, because visual and auditory information in speech seemed to be integrated on a syllabic time scale. Potential applications of this research include noisy workplace in which a worker must extract relevant speech from all the other competing noises.

Acoustic Stimulation↗

PubMed2004

[Comparison of Work Ability Index and cognitive function tests].

The purpose of this study was to evaluate the effect of aging with regard to scores for certain cognitive function tests and WAI (Work Ability Index), and to examine the relationship between cognitive function test scores and work ability as measured by WAI. The subjects were 139 male employees of a factory producing steel plate, and their average age was 48.1 yr (SD 16.4). The WAI and cognitive function tests were conducted and valid scores were obtained from 134 subjects as to WAI, and from 88 subjects as to cognitive function tests. The subjects were divided into two groups: young workers (under 45 yr) and middle-aged to elderly workers (45 yr and over). The WAI scores of the two groups were compared, but no significant differences were observed. Nevertheless, for two WAI items, WAI-2 and WAI-7, the scores of the middle-aged to elderly worker group were significantly higher than those of the young worker group. In contrast, the scores for WAI-3 of the middle-aged to elderly group were significantly lower than those of the young worker group. The cognitive function test scores for the two groups were also compared. The scores for Working Memory test, Tracking test, and Sentence-to-sentence Comparison test of the middle-aged to elderly worker group were significantly lower than those of the younger group. Moreover, for the middle-aged to elderly worker group, the average WAI-3 scores for those with good cognitive function test results and those with poor cognitive function test results were compared, but there were no significant differences. This result shows that deterioration of physical function caused by aging is not related to deterioration of cognitive function caused by aging in the subjects of this study. The reason for this may be that the subjects are blue-collar workers, and thus cognitive functions are less important for their work.

Adult↗

PubMed2004

[Association of working postures and some lifestyles with low back pain in a manufactory].

The aim of this study was to determine the relationship between work and low back pain (LBP) by examining both working postures and the workers' everyday lifestyle. Subjects were 118 male workers in a small-to-medium-sized factory having three kinds of workplaces: the slit line, the packing line, and the crane unit. Working posture analysis with OWAS and interviews were carried out. The result of posture analysis showed that the standing posture with both legs straight and back bent appeared most frequently in all three workplaces. Meanwhile, the prevalence of LBP was almost equal among these groups, with 70% of workers having experienced LBP in each group. But the main cause of LBP differed among the three groups. On the slit line, the result of regression analysis and interview suggested that exercises in the past affected the prevalence of LBP, and that aging and work made LBP worse. On the packing line, many workers were transferred to other positions after a few years, and thus might affect the prevalence of LBP in other workplaces. For the crane unit, it appeared that work in previous positions might affect the occurrence of LBP. Moreover, it seemed that activities in the workplace, rather than lifestyles, contribute to the occurrence of LBP in this factory.

Adult↗

PubMed2003

Effects of screen size and task difficulty on vigilance performance of older adults.

This paper describes an experiment to elucidate the effects of aging on vigilance performance with VDTs. In addition, the experiment was undertaken to evaluate whether the aging effects are affected by the degree of task difficulty and by the screen size of the VDTs. Forty healthy male volunteers were studied in two age groups of 20 participants. In the experiment, the participants were required to perform vigilance tasks, which were presented either on a conventional 17-inch display or a large-sized 110-inch display. The 60-minute task period was divided into three 20-minute phases assigning the tasks with two scenarios of different degrees of difficulty. Performance was measured using reaction time for detection and number of detection errors. The results pointed out three effects: (1) the performance of the vigilance tasks deteriorated more markedly among the older adults than among the younger adults; (2) the between-screen differences on the vigilance performance were significant for the older adults, but not for the younger adults; (3) the effect of screen size was amplified by increasing the degree of task difficulty. These data indicate that screen size and task difficulty have an effect on vigilance performance with VDTs of older adult.

Adult↗

PubMed2002

[How many ergonomics interventions do we have in the field of occupational stress?].

This paper describes handling stress in the workplace from the viewpoint of work conditions and ergonomics. The term expressed in Japanese as "sagyokanri" corresponds to the term "work conditions and ergonomics" in English, which is used internationally in the field. Therefore, "sagyokanri" means considering how to handle work and stress by using ergonomics. The Japanese Journal of Ergonomics is quoted in this discussion of the definition of stress and the lack of countermeasures taken with respect to work conditions and ergonomics as they relate to stress. Finally, it touches on the SACL (Stress Arousal Checklist), one method of evaluating stress which is not very familiar to those in the occupational health field in Japan.

Ergonomics↗