A temporal distinctiveness theory of contextually cued retrieval from memory is presented and applied to recency and modality effects. According to this theory, one part of the mnemonic trace of an item is a representation of the item's time of presentation. Time of presentation may be encoded with a coarse grain (so that it is consistent with a wide range of times) or with a fine grain (so that it is consistent with a narrow range of times). Retrieval proceeds by constructing temporally defined search sets that include representations of items consistent with the temporal bounds of the search set. The temporal width of the search set increases as the retention interval increases. Recency effects arise from retrieval of recently presented items from narrow search sets that include representations of few items; within the context of the search set, these items are distinctive and recalled well. Superiority in recall of recently presented auditory information in comparison with recently presented visual information is attributed to differences in the grain of time of presentation representations for aurally (fine grain) and visually (coarse grain) presented information. Four experiments confirm qualitative and quantitative predictions of the theory, including the prediction of auditory superiority at the beginning of the list when the initial items are temporally distinct.

This study examined the effects of supplementary rest breaks on musculoskeletal discomfort, eyestrain, mood, and performance in data-entry workers. Two rest break schedules were compared in a within-subjects design. Workers alternated between a 'conventional' and a 'supplementary' schedule in 4-week intervals. The conventional schedule contained a 15-min break during the first half of the work shift and a 15-min break during the second half of the shift. The supplementary schedule contained the same two 15-min breaks, and a 5-min break during each hour which otherwise did not contain a break, for a total of 20 extra minutes of break time. Results are based on data from 42 workers. They indicated that discomfort in several areas of the body, and eyestrain, were significantly lower under the supplementary than under the conventional schedule. While symptoms increased from pre- to post-work periods under both schedules, the magnitude of the increases was significantly less under the supplementary schedule. In addition, increases in discomfort of the right forearm, wrist and hand over the course of the work week under the conventional schedule were eliminated under the supplementary schedule. These beneficial effects were obtained without reductions in data-entry performance.

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These results provide further converging evidence that supplementary breaks reliably minimize discomfort and eyestrain without impairing productivity. Low compliance in performing stretches prevented valid assessment of stretching effects. Further research on stretching exercises and exercise compliance is warranted.

The authors examined the impact of a number of job stressors, including sexual harassment and gender-based discrimination, on female construction workers' level of job satisfaction and psychological and physical health. Results from a telephone survey with 211 female laborers indicated that having responsibility for others' safety and having support from supervisors and male coworkers was related to greater job satisfaction. Increased reported psychological symptoms were also related to increased responsibility, as well as skill underutilization, experiencing sexual harassment and gender-based discrimination from supervisors and coworkers, and having to overcompensate at work. Perceptions of overcompensation at work and job uncertainty were positively associated with self-reports of insomnia. Finally, sexual harassment and gender discrimination were positively related to reports of increased nausea and headaches.

These data point to an independent relationship between psychosocial job stress and self-reported occupational injury in SMEs.

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The Prevalence and Correlates of Occupational Injuries in Small-Scale ManufacturingEnterprises: Akinori NAKATA, et al. National Institute of Occupational Safety and Health-Workers involved in small-scale manufacturing businesses are known to comprise a high-risk population for occupational injury. The present study investigated the prevalence and correlates of occupational injury in this population. A self-administered questionnaire that solicited answers about occupational information including injury, demographic characteristics, health conditions and lifestyle factors was collected from a sample of 1,298 workers in 228 small-scale manufacturing enterprises (defined as fewer than 50 workers) aged 16-78 (mean 46) yr in Yashio city, Saitama, Japan (response rate 65.5%). The enterprises were randomly selected from the 2000 edition of the city commercial directory corresponding to the distribution of types of businesses in the city. Occupational injury was assessed by asking subjects, 'Have you ever been injured during your work, including minor scratches and cuts in the previous 1-yr period?' The possible response was either 'yes' or 'no.' The prevalence of study-defined occupational injury among the workers was 35.6% (male 43.0%, female 17.9%). Among job types, manufacturing (44.2%) and driving (43.5%) had high rates of occupational injuries. Similarly, occupational injuries were high in the papermaking (54.5%) and machinery (47.7%) industries. For males, younger age, current or former smoking, insomnia symptoms, and disease(s) currently under treatment were correlated with injury, whereas for females, being unmarried, higher educational status, and insomnia symptoms were the correlating factors. Occupational injury is common among small-scale manufacturing businesses, and is associated with multiple controllable factors. Countermeasures such as prohibiting smoking during work, sleep health education, job safety training for young/inexperienced workers are appropriate methods for eliminating or reducing injuries. (J Occup Health 2006; 48: 366-376)