Photon Sieve Design and Fabrication for Imaging Characteristics Using UAV Flight

The Photon Sieve (PS) team at NASA Langley Research Center (LaRC) began receiving support for the development and characterization of PS devices through the NASA Internal Research & Development Program (IRAD) in 2015. The project involves ascertaining the imaging characteristics of various PS devices. These devices hold the potential to significantly reduce mission costs and improve imaging quality by replacing traditional reflector telescopes. The photon sieve essentially acts as a lens to diffract light to a concentrated point on the focal plane like a Fresnel Zone Plate (FZP). PSs have the potential to focus light to a very small spot which is not limited by the width of the outermost zone as for the FZP and offers a promising solution for high resolution imaging. In the fields of astronomy, remote sensing, and other applications that require imaging of distant objects both on the ground and in the sky, it is often necessary to perform post-process filtering in order to separate noise signals that arise from multiple scattering events near the collection optic. The PS exhibits a novel filtering technique that rejects the unwanted noise without the need for time consuming post processing of the images. This project leverages key Langley resources to design, manufacture, and characterize a series of photon sieve specimens. After a prototype was developed and characterized in the Langley ISO5 optical cleanroom and laboratory, outside testing was conducted via the capture of images of the moon by using a telescopic setup. This next goal of the project is to design and develop a telescope and image capture system as a drone-based instrument payload. The vehicle utilized for the initial demonstration was a NASA hive model 1200 XE-8 research Unmanned Aerial Vehicle (UAV), capable of handling a 20-pound maximum payload with a 25-minute flight time. This NASA Technical Memorandum (NASA-TM) introduces preliminary results obtained using a PS-based imaging system on the UAV. The next version of the telescope structure will be designed around diffractive optical components and commercially available camera electronics to create a lightweight payload

MacDonnell_Cardiomyocyte AJP_supplemental_07Jun22_clean.docx

Supplemental figures to be published with    Activin A Directly Impairs Excitation–Contraction Coupling In Human Cardiomyocytes submitted to AJP Heart and Circulatory Physiology</p

Abstract 14803: Activin A Directly Impaired Human IPSC-cardiomyocyte Contractility and Electrophysiology

Activin A is a homo-dimeric TGF-β family member involved in embryonic development, tissue morphogenesis, and cellular differentiation. Levels of activin A correlate with NYHA functional classification and age dependent cardiac dysfunction; however, no data are available to demonstrate a direct role for activin A in regulating human cardiomyocyte dysfunction. The purpose of this study was to characterize the functional impact of chronic activin A on human cardiomyocyte electrophysiology, contractility, calcium handling, and gene expression. Methods: Human iPSC-cardiomyocytes (iPSC-CM) were supplied by Fujifilm Cellular Dynamics. Calcium transients were captured using the FLIPR Tetra imager and impedance/electrophysiology by the Nanion CardioExcyte96. Cells were plated (50k/well), allowed to reach a stable synchronous monolayer, and dosed with 1nM of activin A (A) at each media change alongside a media control (C) or in the presence of inhibitory anti-activin A antibodies. Gene expression was determined using Taqman. Results: Activin A reduced contractile impedance amplitude (C=9.82±0.30, A=6.82±0.21 Ohms, p&lt;0.01) and slowed relaxation velocity kinetics (C=48.78±2.65, A=35.07±1.07 Ohms/sec, p&lt;0.01). Elongated extracellular field potential durations were observed with activin A treatment compared to control (C=0.49±0.02, A=0.56±0.01 sec, p&lt;0.01). Impaired calcium handling peak amplitude (C=609±99, A= C=447±33 RFU, p&lt;0.05) was also observed alongside slower calcium flux falling times (C=0.52±0.05, A=0.70±0.04 sec, p&lt;0.01). An inhibitory activin-A antibody restored all parameters to control values. Chronic exposure of iPSC-CM to activin A reduced expression of calcium handling genes RYR2 (C=1.01±0.07, A=0.75±0.03, p&lt;0.01) and ATP2A2 (C=1.00±0.05, A=0.89±0.05, p&lt;0.05). Conclusions: Chronic activin A treatment reduced cardiomyocyte contractile amplitude, slowed contractile kinetics, impaired cardiomyocyte calcium handling, elongated the action potential, and reduced expression of genes regulating key calcium handling proteins. These data demonstrate that elevated levels of activin A can directly act on cardiomyocytes and therefore may contribute to cardiac dysfunction in heart failure and aged populations. </jats:p