The objective of this work was to determine the linear and non-linear viscoelastic behavior of abdominal aortic aneurysm thrombus and to study the changes in mechanical properties throughout the thickness of the thrombus. Samples are gathered from thrombi of seven patients. Linear viscoelastic data from oscillatory shear experiments show that the change of properties throughout the thrombus is different for each thrombus. Furthermore the variations found within one thrombus are of the same order of magnitude as the variation between patients. To study the non-linear regime, stress relaxation experiments are performed. To describe the phenomena observed experimentally, a non-linear multimode model is presented. The parameters for this model are obtained by fitting this model successfully to the experiments. The model cannot only describe the average stress response for all thrombus samples but also the highest and lowest stress responses. To determine the influence on the wall stress of the behavior observed the model proposed needs to implemented in the finite element wall stress analysis.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2813187 | PMC |
http://dx.doi.org/10.1007/s10237-007-0080-3 | DOI Listing |
J Sci Food Agric
January 2025
Department of Animal, Veterinary and Food Sciences, University of Idaho, Moscow, ID, USA.
Background: Determining the optimum water absorption capacity of gluten-free flours for an improved breadmaking process has been a challenge because there is no standard method. In the present study, large amplitude oscillatory shear (LAOS) tests were performed to explore the impact of different levels of added water on non-linear viscoelastic response of soy flour dough in comparison to wheat flour dough at a consistency of 500 BU.
Results: Among the LAOS parameters, large strain modulus (G') and large strain rate viscosity (η') were found to better probe the impact of added water amount on non-linear viscoelastic properties of soy flour dough.
Sensors (Basel)
December 2024
Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602, USA.
Flexible high-deflection strain gauges have been demonstrated to be cost-effective and accessible sensors for capturing human biomechanical deformations. However, the interpretation of these sensors is notably more complex compared to conventional strain gauges, particularly during dynamic motion. In addition to the non-linear viscoelastic behavior of the strain gauge material itself, the dynamic response of the sensors is even more difficult to capture due to spikes in the resistance during strain path changes.
View Article and Find Full Text PDFJBMR Plus
January 2025
Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Boston, MA, 02215, United States.
Costal cartilage plays an important functional role in the rib cage, but its mechanical properties have not been well characterized. The objective of this study is to characterize the properties of human costal cartilage and examine the effects of age, sex, rib level, and degree of calcification. We obtained cadaveric costal cartilage samples of ribs 3-6 with intact perichondrium from 24 donors (12 females and 12 males) evenly distributed by age (range 47-94 yr).
View Article and Find Full Text PDFGels
October 2024
Chair of Microfluidics, Faculty of Mechanical Engineering and Marine Technology, University of Rostock, 18059 Rostock, Germany.
The rubber elasticity theory has been lengthily applied to several polymeric hydrogel substances and upgraded from idealistic models to consider imperfections in the polymer network. The theory relies solely on hyperelastic material models in order to provide a description of the elastic polymer network. While this is also applicable to polymer gels, such hydrogels are rather characterized by their water content and visco-elastic mechanical properties.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
POLYMAT and Department of Advanced Polymers and Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal 3, 20018 Donostia-San Sebastián, Spain; IKERBASQUE, Basque Foundation for Science, Plaza Euskadi 5, 48009 Bilbao, Spain. Electronic address:
The generation of long-chain branches (LCB) in biobased and biodegradable polylactide (PLA) by adding different amounts of a chain extender is studied. The rheological and calorimetric behavior have been used to determine the effect of LCB presence and their topology on PLA melt strength and crystallization behavior. Rheological modeling of linear and non-linear viscoelastic shear and extensional properties identified several possible branched structures.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!