AMIR OSTADI MOGHADDAM
PhD Candidate in Mechanical Engineering
Millions of infants are born before 37 weeks gestational age. This condition is called pre-term birth and can cause life-long health problems and cost the society millions of dollars. Understanding and studying pre-term birth can help to prevent long-term problems and reduce the costs by appropriate medical interventions.
However, researchers are not sure about the causes of pre-term birth and current screening tools are not sensitive enough to predict this condition early.
Therefore, I study the tissues that play a role in maintaining pregnancy. My project is on quantifying the mechanical properties associated with cervix remodeling using nanoindentation. I use experimental results and finite element simulations to obtain the mechanical properties of cervix at multiple gestational stages. I investigate the correlations between nanoindentation results, second-harmonic generation images and quantitative ultrasound measurements of cervical remodeling to better understand cervical mechanobiology.
Research Interests: Tissue Mechanics, Nanoindentation, Simulation
SOFT TISSUE CHARACTERIZATION USING NANOINDENTATION
Characterization of the mechanical properties of tissue can help to understand tissue mechanobiology, disease and disease progression. Indentation is increasingly used to measure the local mechanical properties of tissue in different length scales. I use nanoindentation to study the properties of cervix, tendon, and other soft biological materials.
IMPROVING THE MATERIAL PROPERTIES ESTIMATION FROM NANOINDENTATION OF ROUGH SURFACES
Surface roughness decreases the accuracy of nanoindentation measurements by underestimating the Young’s modulus and increasing variability in the data. Even careful sample preparation like polishing and microtoming cannot always produce a smooth surface suitable for nanoindentation, particularly for complex, soft materials like soft tissue. We aim to improve the accuracy of nanoindentation tests of samples with rough surfaces by using computational simulations and introducing improved experimental methods.
QUANTITATIVE ANALYSIS OF 3D COLLAGEN FIBER ORGANIZATION
Collagen is the most abundant protein in mammals. Changes in tissue microstructure can reveal the physiological condition of tissue and affect the mechanical properties. Accurate quantification of 3D collagen fiber organization is an important step for understanding the tissue behavior and structure-function relationships.
"Investigation of dynamic behavior of bone tissue using vibration signal processing"
Moghaddam, Amir Ostadi, Mohammad J. Mahjoob, and Ara Nazarian. "Assigning Material Properties to Finite Element Models of Bone: A New Approach Based on Dynamic Behavior." The 7th International Conference on Computational Methods (ICCM2016). 2016.
Zand, Mahdi Moghimi, and Amir Ostadi Moghaddam. "Pull-in instability and vibrations of a beam micro-gyroscope." Journal of Computational Applied Mechanics 45 (2014): 29-34.
Moghaddam, Amir Ostadi, and Moosa Ayati. "Application of the extended Kalman filter to parameter identification of a micro gyroscope.", Forth International Conference on Acoustics and Vibration.
Moghaddam, A. Ostadi, M. J. Mahjoob, and A. Nazarian. "Bone Remodeling Under Vibration: A Computational Model of Bone Remodeling Incorporating the Modal Behavior of Bone." Journal of biomechanical engineering 140.12 (2018): 121003.