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Krill are filter feeders that consume algae, plankton and detritus, indicating that krill possess an adequate cellulose digesting system. However, less is known about the enzymatic properties of crustacean cellulases compared to termite cellulases. In the present study, 48 kDa-cellulase was highly purified from krill (Euphausia pacifica) in an effort to determine the cleavage specificity of the enzyme. The most notable characteristic of the enzyme was its high activity against both lichenan and carboxymethyl cellulose. The enzyme hydrolyzed internal β-1,4 glycosidic bonds within lichenan as well as carboxymethyl cellulose to release oligosaccharides and glucose. The effects of pH and temperature on the activity and stability of both enzyme activities were almost identical. Cello-oligosaccharides with a degree of polymerization of 4-6 were hydrolyzed by the enzyme, and the same endo-products, cellotriose, cellobiose and glucose, were produced from these oligosaccharides. Neither cellotriose nor cellobiose was hydrolyzed by the enzyme. The enzyme digested filter paper and sea lettuce to produce cellobiose, cellotriose and glucose as major products. Although amino acid sequence homology of the enzyme with termite cellulases and the presence of oligosaccharides in the enzyme suggested that the enzyme is produced by krill itself, further analysis is necessary., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This study sought to compare sickness absence and early retirement at two workplaces in Sweden before and after they had received financial support from the Working Life Fund and implemented vocational rehabilitation activities. Two paper and pulp manufacturing plants were compared and a cohort study was set up. The cohort included everyone born in 1934 or later who was employed in December 1988 (918 employees at Plant A and 1543 at Plant B). For 10 years (1989-98), sick leave and disability pensions were monitored. The periods before and after the intervention (1989-93 and 1994-98, respectively) were compared. Cumulative incidence was calculated for short-, long-term and very long-term sick leave, company pension and early retirement. There was no difference between the plants in terms of the three different outcomes when sick leave was measured before and after the intervention. Sick leave in Period 1 was strongly correlated with an elevated risk of sick leave in Period 2. The cumulative incidence of short-term sick leave decreased from 0.92 (95% CI, 0.91-0.93) in Period 1 to 0.79 (95% CI, 0.77-0.80) in Period 2. For employees in the upper age groups, relative risk for long-term and very long-term sick leave was elevated in both periods. The incidence of early retirement and company pension differed between the companies. We conclude that the size of financial investments in rehabilitation programmes has no significant impact on sickness absence or disability pension, based on a comparison between two paper and pulp manufacturing plants in Sweden during the early 1990s.