The behavioural and metabolic responses of the largemouth bass Micropterus salmoides (Lacépède) to temperature were determined to define optimal thermal conditions. The final preferendum of largemouth bass juveniles determined with acute and gravitation methods was independent of the method (29.0–28.1 °C). The displacement velocity in the horizontal thermal gradient of bass juveniles was 22.4 cm h−1 in the light phase and 22.6 cm h−1 in the dark phase. Oxygen consumption rates in the largemouth bass increased significantly (P<0.05) from 48.8 to 69.4 mg O2 Kg−1 h−1 with an increase in the acclimation temperature from 20 to 33 °C. The temperature quotient (Q10) in the juveniles was 1.37–2.00 in the range of acclimation temperatures of 26–29 and 29–32 °C. The optimum temperature range for growth calculated using Jobling's equation was 28.1–28.6 °C and for Q10 values 26–29 °C. The results are discussed in relation to the use of this information in aquaculture.

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The first step in developing travel time and water quality models in streams is to correctly model solute transport mechanisms. In this paper a comparison between two solute transport models is performed. The parameters of the Transient Storage model (TS) and the Aggregated Dead Zone model (ADZ) are estimated using data of thirty seven tracer experiments carried out under different discharges in five mountain streams of Colombian Los Andes. Calibration is performed with the generalized uncertainty estimation method (GLUE) based on Monte-Carlo simulations. Aspects of model parameters identifiability and model parsimony are analyzed and discussed. The TS model with four parameters shows excellent results during calibration but the model parameters present high interaction and poor identifiability. The ADZ model with two independent and clearly identifiable parameters gives sufficiently precise calibration results. As a conclusion, it is stated that the ADZ model with only two parameters is a parsimonious model that is able to represent solute transport mechanisms of advection and longitudinal dispersion in the studied mountain streams. A simple model parameter estimation methodology as a function of discharge is proposed in this work to be used in prediction mode of travel time and solute transport applications along mountain streams.

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52Twenty-fi ve hundred years ago, Hippocrates bequeathed a set of ethical precepts that emphasized the social transcendence of the practice of medicine and the profound commitment of physicians to serve patients and their families selfl essly and with a pure heart. [1]