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Mark White

Publications and source records attributed to Mark White.

3 recordsLinked to original sources

Ultrasound-based Control of Micro-Bubbles for Exosome Delivery in Treating COVID-19 Lung Damage

The recent COVID-19 pandemic has resulted in high fatality rates, especially for patients who suffer from underlying health issues. One of the more serious symptoms exhibited from patients suffering from an acute COVID-19 infection is breathing difficulties and shortness of breath, which is largely due to the excessive fluid (cellular leakage and cytokine storm) and mucoid debris that have filled lung alveoli, and reduced the surfactant tension resulting in heavy and stiff lungs. In this paper, we propose the use of micro-bubbles filled with exosomes that can be released upon exposure to ultrasound signals as possible rescue therapy in deteriorating COVID-19 patients. Recent studies have shown that exosomes can be used to repair and treat lung damage for patients who have suffered from viral infection. We have conducted simulations to show the efficacy of the ultrasound signals that will penetrate through layers of tissues reaching the alveoli that contain the micro-bubbles. Our results have shown that ultrasound signals with low frequencies are required to oscillate and rupture the polymer-based micro-bubbles. Our proposed system can be used for patients who require immediate rescue treatments for lung damage, as well as for recovered patients who may suffer from viral relapse infection, where the micro-bubbles will remain dormant for a temporary therapeutic window until they are exposed to the ultrasound signals.

physics.med-ph

Near-Infrared Scanning Cavity Ringdown for Optical Loss Characterization of Supermirrors

A cavity ringdown system for probing the spatial variation of optical loss across high-reflectivity mirrors is described. This system is employed to examine substrate-transferred crystalline supermirrors and quantify the effect of manufacturing process imperfections. Excellent agreement is observed between the ringdown-generated spatial measurements and differential interference contrast microscopy images. A 2 mm diameter ringdown scan in the center of a crystalline supermirror reveals highly uniform coating properties with excess loss variations below 1 ppm.

physics.ins-det

The G-Ball, a New Icon for Codon Symmetry and the Genetic Code

A codon table is a useful tool for mapping codons to amino acids as they have been assigned by nature. It has become a scientific icon because of the way it embodies our understanding of this natural process and the way it immediately communicates this understanding. However, advancements in molecular biology over the past several decades must lead to a realization that our basic understanding of genetic translation is fundamentally flawed and incomplete, and, therefore, our icon is inadequate. A better understanding of symmetry and an appreciation for the essential role it has played in codon formation will improve our understanding of nature's coding processes. Incorporation of that symmetry into our icon will facilitate that improvement.

q-bio.OT