| 1. |
|
|
| 2. |
|
|
| 3. |
- Burström, Lage, 1954-, et al.
(författare)
-
Acute effects of vibration on thermal perception thresholds
- 2006
-
Ingår i: Diagnosis of injuries caused by hand-transmitted vibration - 2nd International workshop, Göteborg, 2006. - : Springer Science and Business Media LLC.
-
Konferensbidrag (refereegranskat)abstract
- Objective This study focuses on the acute effects of vibration and how vibrations influence the measures of the thermal perception thresholds during different vibration magnitudes, frequencies, and durations.Methods The fingers of ten healthy subjects, five males and five females, were exposed to vibration under 16 conditions with a combination of different frequency, intensity and exposure time. The vibration frequency was 31.5 and 125 Hz and exposure lasted between 2 and 16 min. The energy-equivalent frequency weighted acceleration, according to ISO 5349-1, for the experimental time of 16 min was 2.5 or 5.0 m/s(2) (r.m.s.), corresponding to a 8-h equivalent acceleration, A(8) of 0.46 and 0.92 m/s(2), respectively. A measure of the thermal perception of cold and warmth was conducted before the different exposures to vibration. Immediately after the vibration exposure the acute effect was measured continuously on the exposed index finger for the first 75 s, followed by 30 s of measures at every minute for a maximum of 10 min. If the subject's thermal thresholds had not recovered, the measures continued for a maximum of 30 min with measurements taken every 5 min.Results For all experimental conditions and 30 s after exposure, the mean changes of the thresholds compared with the pre-test were found to be 0.05 and -0.67C for the warmth and cold thresholds, respectively. The effect of the vibration exposure was only significant on the cold threshold and only for the first minute after exposure when the threshold was decreased. The warmth threshold was not significantly affected at all. The frequency and the exposure time of the vibration stimuli had no significant influence on the perception thresholds for the sensation of cold or warmth. Increased equivalent frequency weighted acceleration resulted in a significant decrease of the subjects' cold threshold, not the warmth. The thresholds were unaffected when changes in the vibration magnitude were expressed as the frequency weighted acceleration or the unweighted acceleration.Conclusion When testing for the thermotactile thresholds, exposure to vibration on the day of a test might influence the results. Until further knowledge is obtained the previous praxis of 2 h avoidance of vibration exposure before assessment is recommended.
|
|
| 4. |
- Burström, Lage, 1954-, et al.
(författare)
-
Influence of vibration exposure on tactile and thermal perception thresholds
- 2009
-
Ingår i: Occup Med (Lond). - : Oxford University Press (OUP). - 1471-8405 .- 0962-7480. ; 59:3, s. 174-9
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS: To establish if intermittent exposure to hand-transmitted vibration had the same effect as continuous exposure on the temporary response of finger tactile and thermal perception thresholds. METHODS: Two laboratory experiments were conducted. In each, 10 healthy subjects, five males and five females, participated. The subjects' fingers were exposed to vibration under four conditions with a combination of different periods of exposure and rest periods. The vibration frequency was 125 Hz and the frequency-weighted acceleration was 5 m/s(2). A measure of the tactile or thermal perception was conducted before the different exposures to vibration. Immediately after the vibration exposure, the acute effect was measured continuously for the first 75 s. This was followed by regular measures for a maximum of 30 min. RESULTS: The results showed that combinations of vibration with different periods of exposure and rest periods significantly influenced vibrotactile perception, but not thermal perception. CONCLUSIONS: These findings suggest that intermittent exposure to hand-transmitted vibration might be more beneficial for the response of the finger vibrotactile sensation than continuous exposure. This finding is inconsistent with the evaluation methods in ISO 5349-1 for vibrotactile sensation, but accurate for thermal perception.
|
|
| 5. |
- Burström, Lage, 1954-, et al.
(författare)
-
Vibrotactile perception and effects of short-term exposure to hand-arm vibration
- 2009
-
Ingår i: The Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 1475-3162 .- 0003-4878. ; 53:5, s. 539-47
-
Tidskriftsartikel (refereegranskat)abstract
- This study clarifies whether the established frequency weighting procedure for evaluating exposure to hand-transmitted vibration can effectively evaluate the temporary changes in vibrotactile perception thresholds due to pre-exposure to vibration. In addition, this study investigates the relationship between changes of the vibrotactile perception thresholds and the normalized energy-equivalent frequency-weighted acceleration. The fingers of 10 healthy subjects, five male and five female, were exposed to vibration under 16 conditions with a combination of different frequencies, intensities, and exposure times. The vibration frequencies were 31.5 and 125 Hz and exposure lasted between 2 and 16 min. According to International Organization for Standardization (ISO) 5349-1, the energy-equivalent frequency-weighted acceleration for the experimental time of 16 min is 2.5 or 5.0 m s(-2) root-mean-square, corresponding to a 8-h equivalent acceleration, A(8), of approximately 0.5 and 0.9 m s(-2), respectively. A measure of the vibrotactile perception thresholds was conducted before the different exposures to vibration. Immediately after the vibration exposure, the acute effect was measured continuously on the exposed index finger for the first 75 s, followed by 30 s of measures every minute for a maximum of 10 min. If the subject's thresholds had not recovered, the measures continued for a maximum of 30 min with measurements taken every 5 min. Pre-exposure to vibration significantly influenced vibrotactile thresholds. This study concludes that the influence on the thresholds depends on the frequency of the vibration stimuli. Increased equivalent frequency-weighted acceleration resulted in a significant change in threshold, but the thresholds were unaffected when changes in the vibration magnitude were expressed as the frequency-weighted acceleration or the unweighted acceleration. Moreover, the frequency of the pre-vibration exposure significantly influenced (up to 25 min after exposure) recovery time of the vibrotactile thresholds. This study shows that the frequency weighting procedure in ISO 5349-1 is unable to predict the produced acute changes in the vibrotactile perception. Moreover, the results imply that the calculation of the 'energy-equivalent' frequency-weighted acceleration does not reflect the acute changes of the vibration perception thresholds due to pre-exposure to vibration. Furthermore, when testing for the vibrotactile thresholds, exposure to vibration on the day of a test might influence the results. Until further knowledge is obtained, the previous practice of 3 h avoidance of vibration exposure before assessment is recommended.
|
|
| 6. |
- Eklöf, Mats, 1953, et al.
(författare)
-
Are simple feedback interventions involving workplace data associated with better working environment and health? A cluster randomized controlled study among Swedish VDU workers
- 2006
-
Ingår i: Appl Ergon. - : Elsevier BV. - 0003-6870. ; 37:2, s. 201-10
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To test whether feedback and discussion of ergonomic and psychosocial working environment data during 1 short session with individual, groups, or supervisors of VDU workers had effects on (1) the quality of implemented modifications in workplace design, working technique, or psychosocial aspects; (2) psychological demands, decision latitude, and social support; (3) comfort during computer work, emotional stress, and prevalence of musculoskeletal symptoms or eye discomfort. METHODS: Thirty-six workgroups from 9 organizations were randomized to 3 feedback conditions (individual, workgroup, supervisor) or control. Follow-up was 6 months after intervention. Questionnaire data aggregated on the workgroup level were used. RESULTS: Effect (positive) on social support was indicated from feedback to supervisors. Conclusion: Feedback and discussion of ergonomic and psychosocial working environment data with supervisors of white-collar VDU workers may have positive effect on social support measured as a group characteristic. Sources of potential bias are discussed.
|
|
| 7. |
- Eklöf, Mats, 1953, et al.
(författare)
-
Feedback of workplace data to individual workers, workgroups or supervisors as a way to stimulate working environment activity: a cluster randomized controlled study.
- 2004
-
Ingår i: International archives of occupational and environmental health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 77:7, s. 505-14
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To test whether feedback and discussion of ergonomic and psychosocial working-environment data during one short session with individual, groups or supervisors of white-collar computer workers had an effect on activity to modify workplace design, working technique and psychosocial aspects of work. METHODS: A total of 36 workgroups from nine organizations representing different trades was randomized (stratified for organization) to three feedback conditions or control with no feedback. Data were collected 1 month before and 6 months after feedback sessions. The effects studied were: (1) change in the proportion of workgroup members who reported any modification regarding workplace design or working technique; (2) change in the proportion of workgroup members who reported any modification regarding psychosocial aspects; (3) average number of modification types regarding workplace design or working technique per individual in a workgroup; (4) average number of modification types regarding psychosocial aspects per individual in a workgroup. RESULTS: All feedback conditions differed positively from controls regarding change in the proportion of workgroup members who reported any modification in workplace design or working technique. No such effect was found for psychosocial aspects. For change in average number of psychosocial modification types per individual in a workgroup an effect was observed for feedback to supervisors. No intervention effect was observed for the average number of modifications in workplace design or working technique per individual in a workgroup. CONCLUSION: Feedback and discussion of ergonomic and psychosocial working-environment data during one short session with individual, groups or supervisors of white-collar computer workers may have a positive effect on how many people in a workgroup modify (or have modifications done regarding) workplace design and working technique. Feedback to supervisors may have an effect on the average number of psychosocial modification types per individual in a workgroup. Feedback to group supervisors appeared to be the most cost-effective variant.
|
|
| 8. |
|
|
| 9. |
- Eriksson, Jesper, 1974, et al.
(författare)
-
Early inequalities in excellent health and performance among young adult women and men in Sweden.
- 2007
-
Ingår i: Gender medicine : official journal of the Partnership for Gender-Specific Medicine at Columbia University. - : Excerpta Medica, Inc.. - 1550-8579 .- 1878-7398. ; 4:2, s. 170-82
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Although health inequality between young adult women and men has been strikingly evident in symptoms of ill health, we found no studies examining these inequalities with a focus on positive health and performance. OBJECTIVE: The aim of the present study was to examine possible inequalities between young adult women and men in a combined assessment of positive health and health-related performance. METHODS: Women and men aged 18 to 25 years studying medicine or computer science at 6 colleges/universities in 5 cities in Sweden were recruited for this study. All respondents answered a Web-based questionnaire regarding health, health-related performance, information and communication technology exposure, mood, and individual factors. A combined assessment of excellent health and health-related performance (EHHP) was defined and tested. Prevalence ratios (PRs) with 95% CIs of EHHP were calculated separately for female and male respondents. To assess potential determinants of EHHP, differences in the relationships between EHHP and the explanatory factors were compared for both sexes. Results: In a study group of young adult students consisting of 1046 women and 1312 men, women were less likely than men to have EHHP (PR 0.90 [95% CI, 0.83-0.98]). This inequality was even stronger within each course of study (medicine or computer science). Health-related factors showed similar patterns of relationship to EHHP for women and men; however, the strength of these relationships differed between the sexes. Logical relationships were observed between EHHP and almost all of the symptoms as well as between EHHP, the mood index, and health-related behavior. CONCLUSIONS: The well-known inequality in symptoms of ill health between young adult women and men was prevalent even in a combined assessment of positive health and health-related performance. That this inequality was prevalent in a relatively homogeneous sample of young adults indicates the importance of gender-based psychological and psychosocial factors beyond the more well-known structural gender-differentiating factors of vertical and horizontal segregation and disproportional responsibilities for domestic work. It may therefore be essential to emphasize these gender-based psychological and psychosocial factors when designing future studies and health promotion programs.
|
|
| 10. |
- Löve, Jesper, 1974, et al.
(författare)
-
Inequalities in maintenance of health and performance between young adult women and men in higher education.
- 2009
-
Ingår i: European journal of public health. - : Oxford University Press (OUP). - 1464-360X .- 1101-1262. ; 19:2, s. 168-74
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Because of ageing populations, most high-income countries are facing an imminent scarcity of labour. Maintenance of health and performance in young adults therefore becomes a crucial prerequisite for sustainable societies. One major obstruction to this accomplishment is the striking health inequalities between young women and young men. Previously these inequalities have mainly been studied in a cross-sectional way, focusing on ill-health. In this study, we compared the prevalence of maintained health and performance between young adult women and men and the predictors for this outcome. METHODS: The cohort consisted of 1266 participants from a homogenous sample of university students in Sweden. A combined assessment of self-rated 'very good' health and un-impaired performance took place at three time points (i.e. maintained health and performance). Potential predictors covered stable conditions in health-related behaviours, conditions at work/school and work-home interference. RESULTS: Young women had less maintained health and performance than young men. No major differences in predictors were found. However, there was a tendency for psychosocial factors to be the most important predictors, especially in women. CONCLUSIONS: That young women had less maintained health and performance in a homogenous sample beyond well-known differentiating factors suggests explanations other than observable structural differences between the sexes. This was also indicated by the importance attached to perceived demands, and work-home interference, especially in women. The combination of less scheduled, and more unscheduled, schoolwork (i.e. time-flexibility) negatively affected the maintenance of health and performance in our study population, suggesting a focus for future studies.
|
|
