Land-surface modelling in hydrological perspective – a review

The purpose of this paper is to provide a review of the different types of energy-based land-surface models (LSMs) and discuss some of the new possibilities that will arise when energy-based LSMs are combined with distributed hydrological modelling. We choose to focus on energy-based approaches, because in comparison to the traditional potential evapotranspiration models, these approaches allow for a stronger link to remote sensing and atmospheric modelling. New opportunities for evaluation of distributed land-surface models through application of remote sensing are discussed in detail, and the difficulties inherent in various evaluation procedures are presented. Finally, the dynamic coupling of hydrological and atmospheric models is explored, and the perspectives of such efforts are discussed

Effect of misonidazole and hyperthermia on the radiosensitivity of a C3H mouse mammary carcinoma and its surrounding normal tissue.

Both misonidazole (MISO) and hyperthermia are known to enhance the radiation response of hypoxic cells, and to be selectively cytotoxic against cells in a hypoxic and acidic environment. The ability of these conditions to modify the effect of irradiation and their individual relationship was studied in a C3H mammary carcinoma and its surrounding skin. Simultaneous treatment with MISO, hyperthermia and radiation increased the radiation effect, with enhancement ratios (ER) of up to about 15 (1 mg/g MISO and 43.5 degrees C for 60 min.). However, such treatment also caused a smaller hyperthermic radiosensitization of the normal tissue, so that the therapeutic ratio was only increased by a factor of about 3 compared to radiation alone. Simultaneous MISO and radiation followed by hyperthermia 4 h later gave a moderate enhancement, with ER up to 3 in the tumour, but with no enhancement of the normal tissue, so that there is a similar 3-fold increase in therapeutic gain. The mechanism by which MISO and hyperthermia enhanced the radiation response may be explained as an independent action of the hypoxic radiosensitization of MISO and the selective hyperthermic cytotoxicity against acidic and chronic hypoxic cells; simultaneous hyperthermia added a further heat-induced general radiosensitization. Surprisingly, no MISO cytotoxicity could be detected in this tumour system, with or without simultaneous hyperthermia. The results indicate that in the proper treatment schedule, MISO may be a valuable addition to a combined hyperthermia and radiation treatment

Using radiotelemetry to study behavioural thermoregulation in insects under field conditions

This is the author accepted manuscript.The final version is available from Wiley via the DOI in this recordThermoregulation is a central aspect of animal physiology. Mobile ectotherms have the potential to influence their temperature through their location and orientation. Behavioural thermoregulation has been extensively studied in insects, particularly in the migratory locust Locusta migratoria. However, most field studies are confined to daytime observations typically using invasive thermocouples with obvious potential to disrupt natural behaviour. We demonstrate that miniature radiotransmitters represent an alternative and less invasive method to study insect thermoregulation. We discuss how this method can be used to study the thermal behaviour of free-ranging animals for extended periods. Specifically, we show that there is a close correlation between temperature recordings from implanted thermocouples in locusts L. migratoria and externally mounted radiotransmitters on the same animals. Our experiments match earlier observations of locust thermoregulatory behaviour confirming that the locusts with transmitters exhibit ‘normal’ thermoregulatory responses to feeding and to infections (behavioural fever). Finally, we demonstrate the practicality of a radiotransmitter-based system by recording natural thermoregulatory behaviour of locusts in a semi-field setting. Our field study showed locusts actively chose warm microclimates during the day and cold microclimates at night. We conclude that the use of radiotelemetry in studies of behavioural thermoregulation in wild insects could provide unique continuous recordings of body temperature over several days. Such data will provide researchers with a more complete understanding of how insects use behavioural thermoregulation in nature.Danish research council (Det Frie Forskningsråd ǀ Natur og Univers