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  • Author: J. Weres x
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Summary

Data sets of wood thermal properties differing in their complexity are presented and discussed. A number of numerical experiments of the heat transfer in wood are performed, and the predicted temperatures are compared to the experimental data obtained for European beech and Scots pine wood. The analysis of similarity of the heat transfer model together with the different empirical data of wood thermal properties to the results of the experiments showed that the lowest accuracy of temperature prediction was obtained for the constant data. Application of advanced models of the thermal conductivity required a large amount of input data and sometimes gave relatively low accuracy in temperature prediction. Application of the thermal conductivity models developed by the authors with the use of the Inverse Heat Transfer Problem approach produced the best temperature prediction accuracy.

Abstract

Glutathione S-transferase (GST) and arylamine N-acetyltransferase 2 (NAT2) metabolise many environmental and chemotherapeutic agents, which influence susceptibility to disease. Polymorphisms in these enzymes result in different host phenotypes and contribute to different disease profiles or responses to toxic or chemotherapeutic agents, depending on their frequency in different populations. GST and NAT2 polymorphisms were investigated in different population groups, including African populations, and a range of allelic frequencies have been observed. The GSTM1 null genotype frequency, reported in this paper in two South African ethnic groups, is the lowest reported (0.19–0.21). In contrast, these same groups have a high GSTT1 null frequency (0.41–0.54), which is considerably higher than in African-Americans, or other Africans. The GSTT1 null frequency is comparable to the Chinese, a population with a very high oesophageal cancer incidence, similar to that in the African group. The frequency of the GSTPi Val105 variant in the South African Xhosas was also high (0.53), differing significantly from the low frequency in other Africans. These variants could therefore be associated with high cancer susceptibility. In addition, the high proportion of NAT2 “fast” alleles may partially explain the high tuberculosis prevalence in South Africans, due to reduced isoniazid efficacy in the presence of rapid acetylation.