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Part 2 of this paper presents an analysis of variance (ANOVA) for investigating the precedence of the various parameters, and the effects of varying these parameters, in assessment of burn injury resulting from the exposure of skin surface to heat sources. A one-dimensional model based on the finite difference method (FDM), as implemented in a spreadsheet software application, is applied to the assessment of burn injury. Henriques' theory of skin burns is used for determining the spatial and temporal extent of tissue damage. The ranks of the effects of various factors were obtained. It was found that the highest ranked factor is the initial tissue temperature followed by the thermal conductivity of the epidermal layer. The effect of blood perfusion rate is ranked much below the combinations of other factors. The results from the present numerical experiment agree well with the results obtained by Palla. Sensitivity analysis of the critical exposure levels was also carried out and results are discussed. In this study, the effects of the various parameters on injury threshold were investigated. Again, the results indicate that the four parameters: thermal conductivity of the epidermis and dermis, convective heat transfer coefficient and initial tissue temperature, have a pronounced influence on assessing the burn injury threshold. It was also found that fat thermal conductivity and blood perfusion rate have no obvious effect on injury threshold. A two-dimensional analysis was further conducted to determine the sensitivity of the predicted injury to the values of frequency factor, P, and apparent activation energy, deltaE, used in the models. Part 1 of this study details the development of the computer models based on the one- and two-dimensional bioheat equations. [ABSTRACT FROM AUTHOR]

The structural response of a large artery is characteristically complex and includes the highly non-linear, history-dependent response of a nonhomogeneous anisotropic structure undergoing finite deformations. The mechanics of the arterial wall has been studied for nearly two centuries. The goals of such research range from the desire to have a basic knowledge and understanding of the mechanics and physiology of this complex structure to the need for data and methods for the design of arterial prostheses. In this paper, the models for arterial wall behaviour are critically reviewed. Firstly, the structure and general characteristics of the arterial wall are discussed. This is followed by a comprehensive review of the constitutive laws. Finally, structural analyses of the arterial wall by mathematical and numerical methods are discussed. Predictions using the authors' preferred models give focus to important issues, and in Part 2 the review and predictions are extended to the fluid solid coupled situation. [ABSTRACT FROM AUTHOR]