HABITAT USE OF AGE - 0 TWAITE SHAD (ALOSA FALLAX LACÉPÈDE, 1803) IN THE TIDAL FRESHWATER REGION OF THE ELBE RIVER, GERMANY.

Between April and August 1997 the distribution of twaite shad larvae in the lower Elbe River downstream the city of Hamburg was examined by ring net, lift net and pop net sampling. During each haul six environmental parameters - water depth, water temperature, conductivity, oxygen concentration, distance from shore line and distance from river channel - were estimated. Twaite shad larvae were found from 26 May to 10 July. Yolk sac larvae were present from 26 May to 25 June. High abundances of twaite shad larvae were found in the side channels and main channels. A canonical correspondence analysis was calculated to evaluate the importance of measured environmental parameters for the distribution of age - 0 fishes. Water depth, distance from shore line and distance from river channel were identified as main parameters for the distribution of species. Twaite shad larvae preferred maximum water depth and distance from shore line and short distances to the river channel. An upstream displacement of the spawning grounds of twaite shad was observed, following a trend first noticed in the early 90th. Nowadays, the location of spawning grounds corresponds to the situation at the beginning of the 19th century. Reduced water pollution is believed to be the main reason for this phenomenon

Productivité des peuplements d'Acacia auriculiformis sur le plateau des Bateke au Zaïre

Productivity of Acacia auriculiformis plantation on the Bateke plateau in Zaire. This paper presents the global results obtained with large scale reforestation made with Acacia auriculiformis on the Bateke Plateau in Zaire. The results show a leguminous species that accept to grow on very poor and very acid soil with a mean annual increment of 12 m3/ha/y of first class fuelwood. The available informations show that the productivity can be improve through better supervision of the plantations and by using selected seeds. In these conditions 15 m3/ha/y could be obtained over 5 years

The role of informal learning in enhancing employability

Paper presented at the 15th biennal EARLI conference for research on Learning and instructio

HABITAT USE OF AGE - 0 TWAITE SHAD (ALOSA FALLAX LACÉPÈDE, 1803) IN THE TIDAL FRESHWATER REGION OF THE ELBE RIVER, GERMANY.

Between April and August 1997 the distribution of twaite shad larvae in the lower Elbe River downstream the city of Hamburg was examined by ring net, lift net and pop net sampling. During each haul six environmental parameters - water depth, water temperature, conductivity, oxygen concentration, distance from shore line and distance from river channel - were estimated. Twaite shad larvae were found from 26 May to 10 July. Yolk sac larvae were present from 26 May to 25 June. High abundances of twaite shad larvae were found in the side channels and main channels. A canonical correspondence analysis was calculated to evaluate the importance of measured environmental parameters for the distribution of age - 0 fishes. Water depth, distance from shore line and distance from river channel were identified as main parameters for the distribution of species. Twaite shad larvae preferred maximum water depth and distance from shore line and short distances to the river channel. An upstream displacement of the spawning grounds of twaite shad was observed, following a trend first noticed in the early 90th. Nowadays, the location of spawning grounds corresponds to the situation at the beginning of the 19th century. Reduced water pollution is believed to be the main reason for this phenomenon

The role of informal learning in enhancing employability

Paper presented at the biennal EARLI conference for research on Learning and instructio

A health economic model to assess the cost-effectiveness of PEG IFN alpha-2a and ribavirin in patients with mild chronic hepatitis C.

According to the current guidelines, it is advised not to treat patients with mild chronic hepatitis C. However, discussions as to giving immediately a treatment (direct treatment) to these patients have started and the incremental cost-effectiveness ratio (ICER) of such strategy is still unknown. The aim of this study was to estimate, in the health care payer perspective, the ICER of a direct treatment of patients with mild chronic hepatitis C in comparison with the strategy of monitoring these patients and treat them when the disease will progress to the state of moderate chronic hepatitis. The treatment assessed was the current standard treatment composed of pegylated interferon alpha-2a and ribavirin. At the beginning of the study, patients were aged 45. Long-term economic and clinical outcomes over a 30-year period were predicted using a Markov simulation model. Data were obtained from published literature. Monte Carlo simulations were used to determine 95% confidence intervals of results. The ICER of a direct treatment with PEG IFN alpha-2a and ribavirin is 23,046 euro/QALY (CI 95% 3,882 euro-42,392 euro) for genotypes 1-4-5-6 and 4,631 euro/QALY (CI 95% 797 euro-7,881 euro) for genotypes 2-3. Sensitivity analysis shows that it is only in extreme circumstances related to the utilities that the ICER for genotypes 1-4-5-6 is unacceptably high for the society (>50,000 euro). Even though a direct treatment is more expensive, it gives the advantage of curing greater number of patients and of increasing quality-adjusted life-years (QALYs), implying that such strategy is generally cost-effective at a threshold of 50,000 euro/QALY