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Analysis of residual stresses in arterial wall
Novák, Kamil ; Fuis, Vladimír (referee) ; Burša, Jiří (advisor)
This thesis deals with computational modeling of the influence of residual stresses in idealized geometry of blood vessels and subsequent application of acquired knowledge to abdominal aortic aneurysm. In the terms of quality of the computational model, we reduced the uncertainties that are included in the computational model without considering the influence of residual stresses. The basic assumption of homogenization significant peaks of the stress between inner and outer vessel wall was met for each level of the computational model Methods that have been used are: deformation method (opening angle method), inverse mechanics of large deformations, fictitious temperature – for linear elastic material and hyperelastic material defined by the constitutive model. Numerical verification was carried out using program ANSYS.
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Stress-strain analysis of anastomosis between artery and artificial vascular graft
Hrubanová, Anna ; Švancara, Pavel (referee) ; Burša, Jiří (advisor)
This bachelor’s thesis deals with anatomy and pathology of arteries and possibilities of their replacement with vascular grafts. The first part of the thesis describes structure and mechanical properties of arterial wall. Furthemore, the biological and mechanical properties of vascular grafts and their influence of healing process are described. The second part of this thesis starts with non-linear calculation of deformation of arterial wall using generalized Hooke’s law. The analytical calculation of connection of artery and vascular graft using cylindrical momentum shell theory was made at the end of this thesis. Description of limitations of this method is also included.
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Analysis of possibilities of analytical approaches suitable for evaluating of stress-strain states of idealized aortic shapes
Turčanová, Michaela ; Burša, Jiří (referee) ; Novák, Kamil (advisor)
The bachelor's thesis deals with possibilities of analytical solution of stress-strain states of arteries. The first part of the thesis gives an information about cardiovascular system and continuum mechanics. The calculation was performed analytically and also numerically using ANSYS program. The analytical calculation was carried out considering non-linear theory of thin and thick-walled vessels involving the residual stress and fictitious temperature approach. Furthermore, the analysis of solutions of abdominal aortic aneurysms was done based on linear theory. Description of other methods of linear theory and techniques of calculating with residual stress are briefly summarized.
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Analysis of impact of direction distribution of collagen fibres in arterial wall on its mechanical properties
Fischer, Jiří ; Návrat, Tomáš (referee) ; Burša, Jiří (advisor)
The aim of this thesis is to analyse literature with focusing on literature about directional distribution of collagen fibres. This knowledge is very important for computational modelling and FEM analysis of arterial wall. Comparison of suitability of different models of directional distribution of collagen fibres is made by fitting of different types of probability density functions. Impact assessment of different collagen fibres distribution on mechanical properties of the arterial wall and impact assessment of wall anisotropy is solved with finite element method. FEM analysis is done on three loading types – uniaxial tension, equibiaxial tension and inflation of artery by internal pressure. Output of this thesis is evaluation of results for various types of collagen fibres arrangement in arterial wall.
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Analysis of impact of direction distribution of collagen fibres in arterial wall on its mechanical properties
Fischer, Jiří ; Návrat, Tomáš (referee) ; Burša, Jiří (advisor)
The aim of this thesis is to analyse literature with focusing on literature about directional distribution of collagen fibres. This knowledge is very important for computational modelling and FEM analysis of arterial wall. Comparison of suitability of different models of directional distribution of collagen fibres is made by fitting of different types of probability density functions. Impact assessment of different collagen fibres distribution on mechanical properties of the arterial wall and impact assessment of wall anisotropy is solved with finite element method. FEM analysis is done on three loading types – uniaxial tension, equibiaxial tension and inflation of artery by internal pressure. Output of this thesis is evaluation of results for various types of collagen fibres arrangement in arterial wall.
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Stress-strain analysis of anastomosis between artery and artificial vascular graft
Hrubanová, Anna ; Švancara, Pavel (referee) ; Burša, Jiří (advisor)
This bachelor’s thesis deals with anatomy and pathology of arteries and possibilities of their replacement with vascular grafts. The first part of the thesis describes structure and mechanical properties of arterial wall. Furthemore, the biological and mechanical properties of vascular grafts and their influence of healing process are described. The second part of this thesis starts with non-linear calculation of deformation of arterial wall using generalized Hooke’s law. The analytical calculation of connection of artery and vascular graft using cylindrical momentum shell theory was made at the end of this thesis. Description of limitations of this method is also included.
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Perivascular adipose tissue in health and disease
Pasáková, Kateřina ; Králová Lesná, Ivana (advisor) ; Janovská, Petra (referee)
Adipose tissue is the biggest endocrine organ in a human body. Its function and composition have been intensively studied due to the rising number of overweight people. The cells of adipose tissue are called adipocytes. The substances that are produced by them are termed adipokines - cytokines secreted by adipocytes. It is possible to distinguish several types of adipose tissue based on its composition - white, brown and transient beige, or based on its location - visceral, subcutaneous and perivascular. Perivascular adipose tissue surrounds most of the blood vessels. Its effect can be inflammatory or anti-inflammatory and it is involved in the process of regulation of vascular tone. Pathology of perivascular adipose tissue can lead to a development of diseases which can directly or indirectly affect the cardiovascular system, and thus it may represent one of the main causes of death in the Western world.
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Analysis of possibilities of analytical approaches suitable for evaluating of stress-strain states of idealized aortic shapes
Turčanová, Michaela ; Burša, Jiří (referee) ; Novák, Kamil (advisor)
The bachelor's thesis deals with possibilities of analytical solution of stress-strain states of arteries. The first part of the thesis gives an information about cardiovascular system and continuum mechanics. The calculation was performed analytically and also numerically using ANSYS program. The analytical calculation was carried out considering non-linear theory of thin and thick-walled vessels involving the residual stress and fictitious temperature approach. Furthermore, the analysis of solutions of abdominal aortic aneurysms was done based on linear theory. Description of other methods of linear theory and techniques of calculating with residual stress are briefly summarized.
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Analysis of residual stresses in arterial wall
Novák, Kamil ; Fuis, Vladimír (referee) ; Burša, Jiří (advisor)
This thesis deals with computational modeling of the influence of residual stresses in idealized geometry of blood vessels and subsequent application of acquired knowledge to abdominal aortic aneurysm. In the terms of quality of the computational model, we reduced the uncertainties that are included in the computational model without considering the influence of residual stresses. The basic assumption of homogenization significant peaks of the stress between inner and outer vessel wall was met for each level of the computational model Methods that have been used are: deformation method (opening angle method), inverse mechanics of large deformations, fictitious temperature – for linear elastic material and hyperelastic material defined by the constitutive model. Numerical verification was carried out using program ANSYS.
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