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Full-Text Articles in Engineering
Influence Of Natural Convection During Dendritic Array Growth Of Metal Alloys (Gradient Freeze Directional Solidification), Suyog N. Mahajan
Influence Of Natural Convection During Dendritic Array Growth Of Metal Alloys (Gradient Freeze Directional Solidification), Suyog N. Mahajan
ETD Archive
Purpose of this study was to examine the microstructural evolution of primary dendrites during Gradient Freeze Directional Solidification process in cylindrical Pb-5.8% Sb alloy samples to generate the ground- based research data to support a future microgravity experiment on the Space Station in a convection free environment. Pb-5.8Sb was selected for this study because of its ease of processing and availability of physical property data which will be required for predicting the dendrite morphology parameters, such as, primary dendrite spacing and dendrite trunk diameter. This alloy is also susceptible to thermosolutal convection caused by density inversion of the met in …
A Microfluidic Platform To Quantify Spatio-Temporal Diffusion Of Chemo-Gradients Within 3d Scaffolds: Applications In Axonal Biology, Michael A. Sawonik
A Microfluidic Platform To Quantify Spatio-Temporal Diffusion Of Chemo-Gradients Within 3d Scaffolds: Applications In Axonal Biology, Michael A. Sawonik
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Axonal outgrowth and guidance play an important role in wiring the developing and regenerating nervous system. The critical role of biomolecular gradients in facilitating this axonal sensitivity and directionality along specific trajectories needs to be elucidated for designing effective therapeutic treatments under injury or disease conditions. However, previous in vitro approaches based on micropipette assay or gel-turning assay proved to be unsuitable or inefficient for precise generation and quantification of diffusive gradients. In this study, we utilized a microfluidic device to generate and quantify physiologically-relevant biomolecular gradients in a simple and reliable manner. Using a combination of computational and experimental …
One-Dimensional Radial Diffusion Of Small Molecules (376 Da) In Bone Tissue, Kurt W. Farrell
One-Dimensional Radial Diffusion Of Small Molecules (376 Da) In Bone Tissue, Kurt W. Farrell
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The flow of nutrients through any biological tissue is important to maintain homeostasis. If the transport process is understood, medical research teams can better design medications, prosthetic implants, and tissue scaffolds. Additionally, transport rates help physicians to better understand disease states and wound healing, including minor injuries such as breaks and sprains, which will aid in better diagnoses. We developed a novel method that measures the rate of diffusion in vitro, of fluorescein sodium salt. Samples were incubated at 37°C in a 5 CO2 atmosphere for various periods of time. Samples were sliced and analyzed using Image-Pro Plus and MATLAB …
Investigations Of Anatomical Connectivity In The Internal Capsule Of Macaques With Diffusion Magnetic Resonance Imaging, Kyle Andrew Ignatius Taljan
Investigations Of Anatomical Connectivity In The Internal Capsule Of Macaques With Diffusion Magnetic Resonance Imaging, Kyle Andrew Ignatius Taljan
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Understanding anatomical connectivity is crucial for improving outcomes of deep brain stimulation surgery. Tractography is a promising method for noninvasively investigating anatomical connectivity, but connections between subcortical regions have not been closely examined by this method. As many connections to subcortical regions converge at the internal capsule (IC), we investigate the connectivity through the IC to three subcortical nuclei (caudate, lentiform nucleus, and thalamus) in 6 macaques. We show that a statistical correction for a known distance-related artifact in tractography results in large changes in connectivity patterns. Our results suggest that care should be taken in using tractography to assess …