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Electrocorticographic Neural Correlates Of Arm Movements And Associated Goal Orientation In Humans, Nicholas Anderson
Electrocorticographic Neural Correlates Of Arm Movements And Associated Goal Orientation In Humans, Nicholas Anderson
All Theses and Dissertations (ETDs)
This thesis analyzed the cortical representation of arm kinematics, target encoding, and goal encoding using subdural electrocorticographic: ECoG) recordings in humans. Using a joystick-based visuomotor task, subjects performed both a standard, delayed match-to-sample center-out task as well as a circular tracing task. Spectral analyses of the ECoG signals clearly showed significant cosine tuning for hand velocity, direction, position and speed throughout the cortex. In particular, velocity tuning was best represented spectrally in a high gamma band from around 90-150 Hz in the primary motor cortical regions. In dorsolateral prefrontal cortex: DLPFC), cortical activity in the 150-250 Hz band of the …
Development And Implementation Of Fully 3d Statistical Image Reconstruction Algorithms For Helical Ct And Half-Ring Pet Insert System, Daniel Keesing
Development And Implementation Of Fully 3d Statistical Image Reconstruction Algorithms For Helical Ct And Half-Ring Pet Insert System, Daniel Keesing
All Theses and Dissertations (ETDs)
X-ray computed tomography: CT) and positron emission tomography: PET) have become widely used imaging modalities for screening, diagnosis, and image-guided treatment planning. Along with the increased clinical use are increased demands for high image quality with reduced ionizing radiation dose to the patient. Despite their significantly high computational cost, statistical iterative reconstruction algorithms are known to reconstruct high-quality images from noisy tomographic datasets. The overall goal of this work is to design statistical reconstruction software for clinical x-ray CT scanners, and for a novel PET system that utilizes high-resolution detectors within the field of view of a whole-body PET scanner. …
Electrocardiographic Consequences Of Electrical And Anatomical Remodeling In Diabetic And Obese Humans, Shuli Wang
Electrocardiographic Consequences Of Electrical And Anatomical Remodeling In Diabetic And Obese Humans, Shuli Wang
All Theses and Dissertations (ETDs)
Background. Diabetes and obesity are two major risk factors for cardiovascular disease. Both can cause changes due to cardiac sources in body-surface potentials: BSPs), that is, in electrocardiograms: ECGs). By identifying the major effects of diabetes and obesity on BSPs, we hope to reveal the electrical phenotype of diabetes in body-surface ECGs in the presence of obesity. Methods. A Bidomain Platform was constructed to link heart-surface transmembrane potentials: TMPs) and BSPs. The Forward-Problem Module of the platform calculates BSPs from a bidomain-model of myocyte TMPs and torso anatomy. The platform also contains a Cardio-myocyte TMP Estimation Module in which an …
A Framework For Temperature Imaging Using The Change In Backscattered Ultrasonic Signals, Yuzheng Guo
A Framework For Temperature Imaging Using The Change In Backscattered Ultrasonic Signals, Yuzheng Guo
All Theses and Dissertations (ETDs)
Hyperthermia is a cancer treatment that elevates tissue temperature to 40 to 43oC. It would benefit from a non-invasive, safe, inexpensive and convenient thermometry to monitor heating patterns. Ultrasound is a modality that meets these requirements. In our initial work, using both prediction and experimental data, we showed that the change in the backscattered energy: CBE) is a potential parameter for TI. CBE, however, was computed in a straightforward yet ad hoc manner. In this work, we developed and exploited a mathematical representation for our approach to TI to optimize temperature accuracy. Non-thermal effects of noise and motion confound the …