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Full-Text Articles in Engineering
Development Of High-Speed Photoacoustic Imaging Technology And Its Applications In Biomedical Research, Yun He
McKelvey School of Engineering Theses & Dissertations
Photoacoustic (PA) tomography (PAT) is a novel imaging modality that combines the fine lateral resolution from optical imaging and the deep penetration from ultrasonic imaging, and provides rich optical-absorption–based images. PAT has been widely used in extracting structural and functional information from both ex vivo tissue samples to in vivo animals and humans with different length scales by imaging various endogenous and exogenous contrasts at the ultraviolet to infrared spectrum. For example, hemoglobin in red blood cells is of particular interest in PAT since it is one of the dominant absorbers in tissue at the visible wavelength.The main focus of …
In Vivo Metabolic And Vascular Response To Hypoxia In Twist Knockdown Murine Breast Cancer, Brandon Sturgill
In Vivo Metabolic And Vascular Response To Hypoxia In Twist Knockdown Murine Breast Cancer, Brandon Sturgill
Graduate Theses and Dissertations
Twist transcription factor is often overexpressed in aggressive tumors. Although needed in early embryonic development for organogenesis, Twist is known to induce an epithelial to mesenchymal transition in cells. In cancer, epithelial to mesenchymal transitions can lead to increased motility and invasiveness. It has also been linked to metabolic reprogramming and increased metastatic risk. Furthermore, metabolic preferences can increase proliferation, enhance metastatic potential, and influence the site of metastasis. We hypothesize that Twist directly affects the metabolism of cancer cells. We expect to see in vivo what we have seen in vitro; Twist overexpression should promote a shift away from …
Modeling And Validation Of Tissue Optical Properties In The Photon Transport Regime, Katelyn Heath
Modeling And Validation Of Tissue Optical Properties In The Photon Transport Regime, Katelyn Heath
Biomedical Engineering Undergraduate Honors Theses
Early detection of changes in epithelial cells, such as the development of neoplastic formations seen in epithelial dysplasia, can indicate regions of the epithelial tissue that are at a high risk for cancerous formation. Using concepts from diffuse reflectance spectroscopy, a Monte Carlo model was developed to predict the reflectance measured by a detector at a small source-detector separation on a microendoscope. The Monte Carlo results were then used to calculate a mathematical relationship between the reflectance and distance that can be used to determine optical properties in a tissue sample. This model was validated with liquid phantoms of specified …
Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue
Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue
Biomedical Engineering Undergraduate Honors Theses
In the field of bedside cardiac diagnostic imaging, Doppler Ultrasound (DU) is the gold standard for diagnosing heart conditions. The largest benefit of DU is its ability to noninvasively image cardiac flow and allow the estimation of blood velocity and quantification of anatomical disease. However, to get correct velocity estimation, the position of the transducer in relation to the flow field needs to be known. This is the problem of angle/direction dependency and limits DUs accuracy when imaging in areas where perfect alignment or exact position of the transducer in relation to flow field is not possible or known, such …
Optical Vortex And Poincaré Analysis For Biophysical Dynamics, Anindya Majumdar
Optical Vortex And Poincaré Analysis For Biophysical Dynamics, Anindya Majumdar
Dissertations, Master's Theses and Master's Reports
Coherent light - such as that from a laser - on interaction with biological tissues, undergoes scattering. This scattered light undergoes interference and the resultant field has randomly added phases and amplitudes. This random interference pattern is known as speckles, and has been the subject of multiple applications, including imaging techniques. These speckle fields inherently contain optical vortices, or phase singularities. These are locations where the intensity (or amplitude) of the interference pattern is zero, and the phase is undefined.
In the research presented in this dissertation, dynamic speckle patterns were obtained through computer simulations as well as laboratory setups …