Predictors and consequences of unemployment in construction and forest work during a 5-year follow-up.
OBJECTIVES: The study investigated whether indicators of health, work conditions, or life-style predict subsequent unemployment and also the unemployment consequences related to health or life-style. METHODS: A questionnaire was administered to 781 male construction and 877 male forest workers (aged 20-49 years and working at the beginning of the study) in 1989 and 1994. Employment status during follow-up was ranked into the following 4 categories according to the employment status and unemployment time: continuously employed, re-employed, short-term (< or = 24 months) unemployed and long-term (> or =24 months) unemployed. RESULTS: The following base-line factors were associated with long-term unemployment during follow-up among the construction workers: age >40 years, poor subjective health, smoking, frequent heavy use of alcohol, low job satisfaction, marital status (single), and unemployment during the year preceding the initial survey. Among the forest workers, age >40 years, frequent stress symptoms, and preceding unemployment entered the model. In addition smoking predicted unemployment among the forest workers with no preceding unemployment. The proportion of regular smokers decreased among the long-term unemployed. Physical exercise was more frequent at the time of follow-up than it was initially, particularly among the unemployed. Stress symptoms increased among the construction workers, but musculoskeletal symptoms decreased significantly among the long-term unemployed. Among the forest workers stress symptoms decreased among the continuously employed and re-employed persons, but musculoskeletal symptoms decreased significantly for them all. CONCLUSIONS: Unemployment among construction workers is to some extent dependent on life-style, health, and job satisfaction in addition to age, marital status, and unemployment history. For forest workers, unemployment is less determined by individual factors. Changes in distress and musculoskeletal symptoms are dependent on employment, particularly among construction workers. (+info)
Similar non-random processes maintain diversity in two tropical rainforests.
Quadrat-based analysis of two rainforest plots of area 50 ha, one in Panama (Barro Colorado Island, BCI) and the other in Malaysia (Pasoh), shows that in both plots recruitment is in general negatively correlated with both numbers and biomass of adult trees of the same species in the same quadrat. At BCI, this effect is not significantly influenced by treefall gaps. In both plots, recruitment of individual species is negatively correlated with the numbers of trees of all species in the quadrats, but not with overall biomass. These observations suggest, but do not prove, widespread frequency-dependent effects produced by pathogens and seed-predators that act most effectively in quadrats crowded with trees. Within-species correlations of mortality with numbers or biomass are not found in either plot, indicating that most frequency-dependent mortality takes place before the trees reach 1 cm in diameter. Stochastic effects caused by BCI's more rapid tree turnover may contribute to a larger variance in diversity from quadrat to quadrat at BCI, although they are not sufficient to explain why BCI has fewer than half as many tree species as Pasoh. Finally, in both plots quadrats with low diversity show a significant increase in diversity over time, and this increase is stronger at BCI. This process, like the frequency-dependence, will tend to maintain diversity over time. In general, these non-random forces that should lead to the maintenance of diversity are slightly stronger at BCI, even though the BCI plot is less diverse than the Pasoh plot. (+info)
Antibody response to OspC-I synthetic peptide derived from outer surface protein C of Borrelia burgdorferi in sera from Japanese forestry workers.
The prevalence of antibodies against Lyme disease spirochaetes in serum samples from 80 forestry workers at high occupational risk of Lyme disease was surveyed by enzyme-linked immunosorbent assay (ELISA) with the OspC-I synthetic peptide. The peptide is part of the outer surface protein C (OspC) amino acid sequence located in the region conserved among Borrelia burgdorferi sensu stricto or sensu lato. Positivity for antibodies against OspC-I was observed in 25 (313%) of the forestry workers. Of these positive cases, 12 (15.0%) and 19 (23.8%) were positive for immunoglobulin M (IgM) and IgG antibody, respectively. Among 62 workers who were negative for IgG antibody against B. garinii or B. japonica in our previous study, 9 (14.5%) and 4 (6.5%) were positive for IgM and IgG antibody, respectively, in OspC-I ELISA. These results demonstrate for the first time that Lyme disease in forestry workers can be revealed using OspC-I ELISA. We conclude that forestry workers who show positive results for antibodies against OspC-I have very likely been exposed to Lyme disease spirochaetes, and that those who show positivity for IgM antibody against OspC-I may be in the early stage of Lyme disease. (+info)
Short report: simultaneous occurrence of Dobrava, Puumala, and Tula Hantaviruses in Slovakia.
The prevalence of antibody to hantaviruses in Slovakia (serum panel n = 2,133) was lower in the western part (0.54%) and higher in the eastern part (1.91%) of the country and was found to be significantly enhanced in a group of forest workers from eastern Slovakia (5.88%). One-third of the IgM-negative convalescent phase sera from patients with hemorrhagic fever with renal syndrome exhibited antibodies reacting predominantly with Puumala virus antigen, while two-thirds had antibodies directed mainly against Hantaan virus antigen. Fine analysis of two Hantaan virus-reactive sera by a focus reduction neutralization test showed that Dobrava hantavirus was the source of these human infections. Initial results of rodent screening indicated the circulation of Dobrava virus in populations of striped field mice (Apodemus agrarius) in eastern Slovakia. (+info)
Evidence of Rickettsia helvetica infection in humans, eastern France.
A 37-year-old man living in eastern France seroconverted to Rickettsia helvetica in August 1997, 4 weeks after the onset of an unexplained febrile illness. Results of a serosurvey of forest workers from the area where the patient lived showed a 9.2% seroprevalence against R. helvetica. This organism may pose a threat for populations exposed to Ixodes ricinus ticks. (+info)
Contributions of land-use history to carbon accumulation in U.S. forests.
Carbon accumulation in forests has been attributed to historical changes in land use and the enhancement of tree growth by CO2 fertilization, N deposition, and climate change. The relative contribution of land use and growth enhancement is estimated by using inventory data from five states spanning a latitudinal gradient in the eastern United States. Land use is the dominant factor governing the rate of carbon accumulation in these states, with growth enhancement contributing far less than previously reported. The estimated fraction of aboveground net ecosystem production due to growth enhancement is 2.0 +/- 4.4%, with the remainder due to land use. (+info)
Comparison of expert-rater methods for assessing psychosocial job strain.
OBJECTIVES: This study tested the reliability and validity of industry- and mill-level expert methods for measuring psychosocial work conditions in British Columbia sawmills using the demand-control model. METHODS: In the industry-level method 4 sawmill job evaluators estimated psychosocial work conditions at a generic sawmill. In the mill-level method panels of experienced sawmill workers estimated psychosocial work conditions at 3 sawmills. Scores for psychosocial work conditions were developed using both expert methods and applied to job titles in a sawmill worker database containing self-reported health status and heart disease. The interrater reliability and the concurrent and predictive validity of the expert rater methods were assessed. RESULTS: The interrater reliability and concurrent reliability were higher for the mill-level method than for the industry-level method. For all the psychosocial variables the reliability for the mill-level method was greater than 0.90. The predictive validity results were inconclusive. CONCLUSIONS: The greater reliability and concurrent validity of the mill-level method indicates that panels of experienced workers should be considered as potential experts in future studies measuring psychosocial work conditions. (+info)
Longitudinal study on work related and individual risk factors affecting radiating neck pain.
OBJECTIVES: To study the effects of work related and individual factors affecting radiating neck pain. METHODS: A longitudinal study was carried out with repeated measurements. A total of 5180 Finnish forest industry workers replied to a questionnaire survey in 1992 (response rate 75%). Response rates to follow up questionnaires in 1993, 1994, and 1995 were 83%, 77%, and 90%, respectively. The outcome variable was the number of days with radiating neck pain during the preceding 12 months with three levels (<8, 8-30, >30 days). The generalised estimating equations method was used to fit a marginal model and a transition model was used in a predictive analysis. RESULTS: Items showing associations with radiating neck pain in both analyses were sex, age, body mass index, smoking, duration of work with a hand above shoulder level, mental stress, and other musculoskeletal pains. In the transition model, radiating neck pain in a previous questionnaire was included in the model. Although it was a strong predictor, the variables already mentioned retained their significance. CONCLUSION: Programmes targeted to reduce physical load at work, mental stress, being overweight, and smoking could potentially prevent radiating neck pain. (+info)