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Mesh-Based Fourier Imaging For Biological And Security Applications, Danielle Justine Hayden
Mesh-Based Fourier Imaging For Biological And Security Applications, Danielle Justine Hayden
Legacy Theses & Dissertations (2009 - 2024)
Traditional x-ray imaging provides only low contrast from low atomic number materials, like soft tissue, due to the small attenuation variations producing very small intensity changes. Higher contrast can be achieved through phase information. The phase change is obtained from the x-ray refracting in a sample, or phase object, due to the difference in refractive indexes. This causes a small angular deviation from the original path. Phase contrast imaging has not been realized in everyday practice due to the requirement for large spatial coherence width of the x-ray beam which typically requires sources on the order of 10-50 m, the …
Dna Aptamer-Based Smart Mri Contrast Agent For Dopamine, Angel D. Thompson
Dna Aptamer-Based Smart Mri Contrast Agent For Dopamine, Angel D. Thompson
Legacy Theses & Dissertations (2009 - 2024)
A smart contrast agent is a molecule whose relaxivity changes in response to a biological trigger such as a biomolecule, enzymatic activity, or pH. The focus of my graduate project was to develop a DNA aptamer-based smart MRI contrast agent capable of sensing dopamine. Aptamers are single-stranded oligonucleotides that form stable three-dimensional structures efficient in binding with high affinity and specificity for a range of targets. The DNA aptamer has an attached lanthanide-based probe, consisting of a metal ion Gd(III) and a macrocyclic DOTA ligand. The aptamer was assembled using solid phase oligonucleotide synthesis. Nuclear magnetic resonance was used to …
Coherent Scatter And Grid-Based Phase Imaging For Materials Discrimination, Sean Niccholas Starr-Baier
Coherent Scatter And Grid-Based Phase Imaging For Materials Discrimination, Sean Niccholas Starr-Baier
Legacy Theses & Dissertations (2009 - 2024)
Traditional X-Ray images provide a meaningful way to differentiate between materials with differing attenuation coefficients. The low contrast provided by this method for materials of low electron density or similar attenuation is a limitation of traditional radiography. Two alternatives have presented themselves as viable candidates for widening the viability of X-Ray imaging, Coherent scatter, and phase contrast imaging provide a means to distinguish between objects of both low absorption and similar attenuation.