Rhizarthrosis in banknote processing workers: a retrospective cohort study.

BACKGROUND: Rhizarthrosis, or osteoarthritis of the base of the thumb, is a common condition affecting 10-30% of the population over the age of 60. Whether it is an occupational disease has been the subject of debate as epidemiological studies on the correlation between physical stress and the presence of rhizarthrosis have shown conflicting results. AIMS: To study the correlation between the prevalence of rhizarthrosis and the time spent by employees manually processing banknotes at the National Bank of Belgium (NBB). METHODS: We followed NBB employees currently or previously holding job titles involving the manual or automated processing of banknotes. Each participant's job history was carefully reconstructed and the number of months holding certain job titles determined. Each participant was clinically and radiologically examined for the presence of rhizarthrosis in both hands. Its presence was scored by a combination of clinical and radiological criteria. RESULTS: There were 195 participants. The prevalence of rhizarthrosis was 27% in women (mean age: 52.3 ± 4.4 years) and 17% in men (mean age: 53.2). The odds ratio (OR) for rhizarthrosis after 10 years' full-time overall exposure was significantly higher [OR 10 years: 1.53 (1.03-2.28)]. However, one particular job, 'manual counting', described by participants as highly straining and severely taxing on the thumbs, did not show a significantly higher prevalence of rhizarthrosis. CONCLUSIONS: Our study confirmed the correlation between the presence of rhizarthrosis and age, gender and general manual labour, in particular banknote processing, but found no link with one specific job-manual counting.

Epidemiological research of twig scab on pear as basis for a rational and ecological disease management.

Scab is one of the key parasites in fruit growth. In favourable weather conditions for the pathogen, a complete harvest can be destroyed if no control measurements are undertaken. The scab fungi on pear and apple are two distinct species. They have, however, a similar biological cycle. Despite the similarities, there are also clear differences and these differences are significant for the control of the pathogen. Pear scab does not only infect fruit and leaves as apple scab does, but also infects twigs. Especially in organic fruit growing, twig scab is a big problem. Once twig scab occurs, it seems to be impossible to get rid of scab in these orchards. The only possibility for the fruit grower in this case is a strict spraying schedule to ensure no further spread of the infection. The main goal of the project is a thorough study of the pear scab fungi (biology, sensitivity of different plant parts and cultivars, dispersal of the fungi and infection conditions, the pathogenicity and characterization of different biotypes) to unravel the life of the fungi and to develop a better control strategy. A better control strategy means a reduced fungicide use and a reduction of fungicide residue on the fruits at harvest, without a reduction of the quality of the fruits and cost effectiveness for the fruit grower. Special attention in the project goes to the role and the control of twig scab. The first results of this project will be shown.

Combinations of soil fumigants for methyl-bromide replacement.

The development programme synergistically combining dazomet and 1,3-dichloropropene at reduced dose rates for broad spectrum soil disinfestation was continued with the simultaneous application of dazomet and the potential soil fumigant dimethyl disulfide (DMDS). Combinations were compared to the separately applied fumigants in soil column experiments allowing comparison of treatments, soil conditions and dose rates. Efficacy over the depth profile in experimental soil columns was studied with packed soil buried target organisms: fungi, nematodes and seeds. It was shown that the combination of 20 g Basamid (98% dazomet) and 40 ml DMDS/m2, even at short fumigation period (1 week), under well controlled conditions performs very well both on the level of broad activity as on depth activity. Studied factors determining fumigant performance are: soil temperature, soil moisture content and the presence of organic matter. Finally, activity of this dazomet plus DMDS combination at reduced dose rates was tested on different phytopathogenic fungal targets as well as on a Trichoderma fungus. It was shown that weaker performance of full rate separately applied compounds could become compensated by simultaneous application at half of the recommended dose rates of each. Appropriate soil conditions were confirmed as well as the necessity to avoid high organic matter content in soil or to increase dose rate at high content for successful soil disinfestation. It is also emphasized that both methyl isothiocyanate (MITC), that is the active generated in soil from dazomet, and DMDS are naturally occurring compounds similar to the actives generated by 'bio-fumigation' practices. The advantage of synthetic generators is the better control upon effective dose rate.

Muscular activity and perimetric thresholds.

Static and kinetic peripheral luminance thresholds were measured by means of a Goldmann perimeter along oblique meridians in monocular vision. In a main group of 33 young and healthy subjects these measurements and visual reaction time assessments were made successively at rest, when cycling without load, when cycling with load using aerobic energy supply, when cycling with load using anaerobic energy supply and twice again at rest. Another group of subjects did not pedal and served as controls. The results show that peripheral visual sensitivity increases faintly but significantly during muscular exercise. When assessed by static perimetry the sensitivity increase is grossly proportional with load and is thus greatest in anaerobic condition, while kinetic sensitivity differs by a sensitivity decrease when passing from aerobic to anaerobic exercise. The reported modifications in perimetric sensitivity during dynamic muscular exercise seem related to changes in alertness.