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This study evaluates the effect of gender, handle size and vibration levels on the ability to perform a precision task and on ratings of discomfort and difficulty. Forty subjects, 20 women and 20 men, performed a task using handles of three different diameters while being exposed to two different vibration levels. The task was to follow a straight line on a computer screen by grasping the handle. After each test round, the subjects rated the perceived difficulty and discomfort according to Borg's category-ratio scale. Anthropometrical measures and assessments of maximum grip strength were also made. The male subjects performed better in all the tests. No gender difference was shown in the ratings of difficulty and discomfort. The ratings of discomfort, but not the performance itself, differed between the vibration levels. Handle size, anthropometric measures, and maximum grip strength influenced the female subjects’ results and ratings more than the male subjects. Fifteen female subjects and ten male subjects were able to rank only one of the handles or did not realize that the handles had been changed between the test rounds. The results indicate that there should be considerations to gender differences in the design of machines and tools. Relevance to industry This paper describes how physical characteristics affect the ability to perform a task more in women than in men. The results contribute to the discussion of the situation of women in male-dominated occupations using machines and tools designed for men.

In 1955, the mountain birch forest in the Abisko valley of northern Sweden was defoliated by caterpillars of the moth Epirrita autumnata with death of stems of the polycormic trees as a result. Since then, some stands have recovered from surviving trees, producing new shoots while other stands became rejuvenated from basal sprouts. Usually, basal sprouting occurs after the death of whole trees or stems. In this case, extensive basal sprouting occurred in spite of only minor stem mortality. Two associated explanations to these differences were explored: (i) the abundant basal sprouting was caused by more top damage (and, hence, a reduced apical dominance) than in stands with less sprouting, (ii) this top damage was caused by a higher caterpillar density in the upper part of trees. Studies made during the outbreak and reported here confirm (i) and reject (ii) by showing that caterpillar densities were lower in the upper part of crowns than in the lower. The more extensive damage in the upper part of crowns may have several explanations. However, a specific sequence of events seemed to produce the rejuvenated stand. The sequence included a severe stress existing before the outbreak (as indicated by a decreased radial stem growth) which was increased by defoliations in two successive years. We, therefore, hypothesize that top dieback was caused by between – and within – stem competition for depleted carbohydrate resources at the expense of tree tops. The contributions of different types of sprouts to the rejuvenation and prerequisites for an outbreak to rejuvenate stands are discussed.

Treatment of deep venous thrombosis with low molecular weight heparin (LMWH-Novo, Logiparin) was carried out with two different doses of Logiparin, 75 XaI U/kg b.w. twice daily and 150 XaI U/kg b.w. once daily subcutaneously for 5 days. Simultaneously warfarin was given from the first day of heparin treatment. Mean age of the twenty patients was 65 years and one third was females. No serious side effects, hematomas, pulmonary emboli or signs of recurrent thrombosis occurred during treatment with either dose regime. Venografic assessment with Marder scoring one week after initiation of Logiparin treatment showed a slight not significant improvement apparent in 40 % of the patients. The activities of F-IIaI and F-XaI in the blood plasma were found to increase after injection of Logiparin. These two parameters seem to be the most suitable for monitoring the effect during treatment. For future studies on the therapeutic effect of Logiparin in deep venous thrombosis a single dose of 150 to 200 F-XaI activity per 24 hours seems to be most suitable.