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Objectives-To investigate the prevalence of neck, shoulder, and arm pain (NSAP) as well as low back pain (LBP) among hospital nurses, and to examine the association of work tasks and self estimated risk factors with NSAP and LBP. Methods-A cross sectional study was carried out in a national university hospital in Japan. Full time registered nurses in the wards (n=314) were selected for analysis. The questionnaire was composed of items on demographic conditions, severity of workloads in actual tasks, self estimated risk factors for fatigue, and musculoskeletal pain in the previous month. Rate ratios (RRs) and 95% confidence intervals (95% CIs) were calculated by the Cox's proportional hazards model to study the association of pain with variables related to work and demographic conditions. Results-The prevalences of low back, shoulder, neck, and arm pain in the previous month were 54.7%, 42.8%, 31.3%, and 18.6%, respectively. The prevalence of musculoskeletal symptoms among hospital nurses was higher than in previous studies. In the Cox's models for LBP and NSAP, there were no significant associations between musculoskeletal pain and the items related to work and demographic conditions. The RRs for LBP tended to be relatively higher for "accepting emergency patients" and some actual tasks. Some items of self estimated risk factors for fatigue tended to have relatively higher RRs for LBP and NSAP. Conclusions-It was suggested that musculoskeletal pain among hospital nurses may have associations with some actual tasks and items related to work postures, work control, and work organisation. Further studies, however, are necessary, as clear evidence of this potential association was not shown in the study.

The conversion of methanol into hydrocarbons over ZSM-5 zeolites has been investigated using a gas-recirculation system. The conversion proceeds autocatalytically. The reaction rate is greatly enhanced by the addition of ethylene or cis-but-2-ene, indicating that the autocatalysis is caused by the reaction of olefin and methanol. Infrared studies have revealed that methoxyl groups (-OCD,) are formed by the reaction of surface hydroxyl groups and methanol molecules (CD,OH), and they decompose to reproduce hydroxyl groups (-OD), giving hydrocarbons. The reaction mechanism in which methyl carbonium ions attack the C-H bond of methanol or dimethyl ether molecules is proposed. Methyl carbonium ions are supposed to be released from extensively polarised methoxyl groups formed by the reaction of methanol molecules and strong Bronsted-acid sites. In fact, strongly acidic materials, Nafion H and heteropolyacids, were found effective for methanol conversion. A semiquantitative analysis of the autocatalytic phenomenon in methanol conversion is also presented.

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The dynamic nature of the protons in H−ZSM-5 was examined by the temperature dependence of 1H MAS NMR in the range 298−473 K. The line width of 1H MAS NMR of acidic protons increased, and through maximum it decreased. The intensity of the spinning sidebands monotonically decreased, and they almost disappeared upon raising the temperature. This temperature dependence of the spectrum was explained by the thermal motion of protons. The correlation times and the activation energies for proton mobility were estimated. The estimated values of the activation energy are 17−20 kJ mol-1.

Objectives-To investigate the prevalence and risk factors of epicondylitis among cooks in nursery schools in a cross sectional study because they are suspected to have strenuous workloads on the hands and arms. Methods-Prevalence of epicondylitis among 209 nursery school cooks and 366 control workers aged 40-59 were studied. Both groups consisted of women workers chosen from 1299 subjects who agreed to participate from 1329 social welfare employees in a city. All workers were interviewed with a questionnaire and had a clinical examination of the tenderness to palpation of epicondyles and epicondylar pain provoked by resisted extension and flexion of the wrist. Results-Nursery school cooks had a significantly higher prevalence of epicondylitis (11.5%) than the controls (2.5%). In a logistic regression model, job title of the cook was also found to have a strong association with epicondylitis (odds ratio (OR) 5.4, 95% confidence interval (95% CI) 2.4 to 11.9) after adjustment for age, body length, and body mass index. Weaker associations were also found between epicondylitis and suspected job stress or workload scores for mechanical workload and psychosocial stressors based on factor analysis. Conclusions-This study supported the hypothesis that nursery school cooks had a higher prevalence of epicondylitis than other workers with less strenuous hand and arm tasks. It was suggested that risk factors of epicondylitis would be multifactorial, including mechanical workload and psychosocial factors. (Occup Environ Med 1998;55:172-179) Keywords: epicondylitis; cooks; cross sectional There have been several studies reporting a higher prevalence of musculoskeletal problems in cooks than in other occupational workers.