RESUMO
The NOAA Deep Space Climate Observatory (DSCOVR) spacecraft was launched on February 11, 2015, and in June 2015 achieved its orbit at the first Lagrange point or L1, 1.5 million km from Earth towards the Sun. There are two NASA Earth observing instruments onboard: the Earth Polychromatic Imaging Camera (EPIC) and the National Institute of Standards and Technology Advanced Radiometer (NISTAR). The purpose of this paper is to describe various capabilities of the DSCOVR/EPIC instrument. EPIC views the entire sunlit Earth from sunrise to sunset at the backscattering direction (scattering angles between 168.5° and 175.5°) with 10 narrowband filters: 317, 325, 340, 388, 443, 552, 680, 688, 764 and 779 nm. We discuss a number of pre-processingsteps necessary for EPIC calibration including the geolocation algorithm and the radiometric calibration for each wavelength channel in terms of EPIC counts/second for conversion to reflectance units. The principal EPIC products are total ozone O3amount, scene reflectivity, erythemal irradiance, UV aerosol properties, sulfur dioxide SO2 for volcanic eruptions, surface spectral reflectance, vegetation properties, and cloud products including cloud height. Finally, we describe the observation of horizontally oriented ice crystals in clouds and the unexpected use of the O2 B-band absorption for vegetation properties.
RESUMO
To evaluate the feasibility of implementing a pulse oximetry screening protocol at a city of mild elevation with a specific focus on the false-positive screening rate. Pulse oximetry screening was performed according to the proposed guidelines endorsed by the American Academy of Pediatrics at a center in Tucson, AZ, at an elevation of 2,643 ft (806 m). During a 10-month period in 2012, 1069 full-term asymptomatic newborns were screened ≥ 24 h after birth. The mean preductal oxygen saturation was 98.5 ± 1.3 % (range 92-100 %), and the mean postductal oxygen saturation was 98.6 ± 1.3 % (range 94-100 %). Of 1,069 patients screened, 7 were excluded secondary to protocol violations, and 1 screened positive. An echocardiogram was performed on the newborn with the positive screen, and it was normal with the exception of right-to-left shunting across a patent foramen ovale. The false-positive rate was 1/1,062 or 0.094 %. The pulse oximetry screening guidelines recommended by the American Academy of Pediatrics are feasible at an elevation of 2,643 ft (806 m) with a low false-positive rate. Adjustments to the protocol are not required for centers at elevations ≤ 2,643 ft. Future studies at greater elevations are warranted.