The radiosity method of radiant interchange analysis of enclosures was used to predict the intensity and the uniformity of thermal radiation within a controlled environment chamber. The chamber was designed for testing the effects of infrared radiation on young broilers. The walls of the chamber were assumed to be grey and separated by a radiatively non-participating medium. Also the black globe thermometer method was used to calculate the incident radiation at different locations in the chamber. Then, the results obtained by the two mentioned methods, were compared. Two separate experiments were designed for different purposes. The first experiment was to study the influence of infrared radiation on poultry. In this experiment, two levels of radiation were tested and the results were compared to those obtained by use of a conventional heat lamp brooding system. The second experiment was to compare a controlled temperature, warm air brooding system, to a conventional heat lamp brooding system. The relative effects in both sets of experiments were measured by use of the weekly growth rate index. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

Bystander effects are traditionally known as a phenomenon whereby unexposed cells exhibit the molecular symptoms of stress exposure when adjacent or nearby cells are traversed by ionizing radiation. However, the realm of bystander effects can be expanded to include any systemic changes to cellular homeostasis in response to a number of biotic or abiotic stresses, in any molecular system. This thesis encompasses three independent experiments looking at bystander and bystander-like responses in both plant and animal models. In plants, an investigation into the regulation of small RNAs has given us some insights into the regulation of the plant hormone auxin in both stress-treated and systemic (bystander) leaves. Another plant model shows that a bystander-like plant-plant signal can be induced upon ionizing radiation to increase the genome instability of neighbouring unexposed (bystander) plants. In animals, it is shown that the microRNAome is largely affected in the bystander cells in a three-dimensional human tissue model. In silico and bioinfomatic analysis of this data provide us with clues as to the nature of bystander signalling in this human ‘in vivo’ model. / xiv, 141 p. : ill. ; 29 cm.