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Jun Li

Publications and source records attributed to Jun Li.

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Homogenized Water Vapor Absorption Band Radiances From International Geostationary Satellites

In the past 20+ years, GEO Imagers with infrared 6.5‐μm bands have been observing the Earth's atmosphere, providing useful information of upper tropospheric moisture. Due to the instrumental differences and local viewing angles in GEO satellites, these observations are not consistent for generating climate data records (CDRs). In this study, a methodology has been developed to homogenize the 6.5‐μm radiances from the international GEO satellites, to generate a consistent CDR. Validations with Infrared Atmospheric Sounding Interferometer radiances from Metops for 2015–2017for seven GEO Imager sensors show that the GEO radiances are homogenized well with small standard deviation and biases of the differences (smaller for newer sensors), temporally stable radiometric accuracy, and weak angle dependency (even weaker for sensors with two water vapor bands). The homogenized 20+ years of consistent 6.5‐μm radiance CDR can be used to evaluate reanalysis and climate models, especially the diurnal variation of the model simulation.

Water Vapor↗
NASA NTRSDate not supplied

Monitoring Biomarkers for Muscular Atrophy using an Electronic Chip for Astronaut Health

Skeletal muscle atrophy is a serious health problem for astronauts in long-duration space flight under microgravity conditions. Preventative measures against muscle atrophy require specific exercise and dietary regimens. Preemptive measurements to improve treatment have the potential to streamline these regimens, decreasing their daily footprint and increasing astronaut quality of life. The objective of our proposed project is to (1) develop a fully integrated disposable microelectrode array chip (with the size of a stamp) that can be interfaced with a handheld electronic system for simultaneous detection of the a panel of biomarkers to monitor the progression of skeletal muscle atrophy due to disuse under microgravity in long-duration spaceflights; and (2) use such quantitative information to guide the combined countermeasures of physical exercise and pharmaceuticals (i.e. specific protease inhibitors) so that the intensity, duration and frequency of exercise can be reduced.

Biosensing↗