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L L Cole

Publications and source records attributed to L L Cole.

6 recordsLinked to original sources

Work schedule and task factors in upper-extremity fatigue.

We tested the combined effects of work schedule and task factors on upper-extremity fatigue in the laboratory during 8-h and 12-h shift schedules. Participants performed a simulated manual assembly task at three repetition rates and three torque loads and self-adjusted their work cycle duration to maintain fatigue at moderate levels. Work cycle durations decreased with increases in both load level and repetition rate. Fatigue was observed more quickly with increasing time on shifts and during night shifts compared with day shifts. Work schedule effects were most apparent at lighter workloads, with minimal differences at higher workloads. The highest fatigue levels were observed during 12-h night shifts, with similar levels reached by the end of both the week of 8-h night shifts and the week of 12-h day shifts. Overall durations were 20%-30% shorter than in previous short-term studies, which was likely a result of the more realistic work schedules used in this study. Results from this study could be applied to the design of work-rest schedules for manual tasks involving the upper extremities.

Adult↗

The impact of keyboard design on comfort and productivity in a text-entry task.

Concerns have arisen that the keyboard is a causal factor in the development of work-related musculoskeletal disorders (WRMDs) among video display terminal (VDT) operators. A number of alternative keyboard designs have been developed with altered geometry in an effort to improve comfort in keyboard operation. However, few data are available to substantiate whether these new keyboard designs are actually effective in reducing discomfort and musculoskeletal problems in users. The purpose of this study was to provide data on the efficacy of certain alternative keyboard design features (e.g. splitting the keyboard in half, and laterally inclining the keyboard halves) in reducing fatigue and musculoskeletal discomfort among keyboard operators. The study also explored the effects of these design features on performance. Fifty subjects performed a text-entry task for one day on a standard keyboard, then were assigned to one of five keyboard conditions for an evaluation period of two days (i.e. 10 subjects/condition). Outcome measures included performance (i.e. keystrokes/h, errors/h) and self-report measures of discomfort and fatigue. The results indicated an initial decline in productivity when subjects began typing on two of the alternative keyboards, but these productivity losses were recovered within the two-day evaluation period. The results also indicated no significant differences between keyboard conditions in discomfort and fatigue. These results suggest a minimal impact of the keyboard design features examined in this study on productivity, comfort and fatigue, at least after two days of exposure.

Adult↗

Psychosocial correlates of harassment, threats and fear of violence in the workplace.

OBJECTIVES: The purpose of this study was to investigate work climate factors and structural job aspects as predictors of workplace violence, with particular attention to the relative influence of both sets of factors. METHODS: Telephone survey data collected by a large midwestern insurance company were analyzed. Interviewers asked 598 full-time workers about their work climate, structural job aspects, and subject and workplace demographics, all of which were used as predictor variables in regression analyses. The participants were also asked about incidents of threats, harassment, physical attacks, and fear of becoming a victim of workplace violence, all of which were used as outcome measures. RESULTS: Separate logistic regressions were carried out for each of the outcome measures. The study identified a variety of factors which appear to place workers at risk of nonfatal occupational violence. Work climate variables, such as co-worker support and work group harmony, were predictive of threats, harassment, and fear of becoming a victim of violence. Structural aspects of the job, such as work schedule, were also significant in predicting threats and fear of becoming a victim of violence, but they were not predictive of harassment. CONCLUSIONS: This is the first study which suggests that both work climate and structural aspects of work may be important in promoting workplace violence. This finding suggests that intervention strategies should consider organizational and climate issues in addition to basic security measures.

Adult↗

Experimental influenza B virus toxicity in mice. A possible model for Reye's syndrome.

Mice intravenously injected with concentrated infectious influenza B/Lee/40 virus (LD50 = 6400 hemagglutinin units) developed lethargy, seizures, coma, and death 1 to 3 days later. The cerebrospinal fluid cell count was normal. Serum glutamic oxaloacetic transaminase levels increased 19-fold and plasma ammonia levels elevated 2.6-fold over control values. Serum bilirubin levels remained normal. Microvesicular fatty metamorphosis developed in the liver, whereas the brain showed mild cerebral edema without inflammatory changes. Viral propagation did not occur in liver or brain, but viral hemagglutinin, neuraminidase, and probably nucleoprotein antigens were produced in hepatocytes. Many of the clinical, biochemical, and pathologic features of the mouse illness are similar to those seen in Reye's syndrome.

Animals↗

Drug addiction.

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Humans↗