Publications by authors named "A C Faler"

2 Publications

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Optical communications downlink from a low-earth orbiting 1.5U CubeSat.

Opt Express 2019 Aug;27(17):24382-24392

In this article, we present the first demonstration of an optical communications downlink from a low-earth orbiting free-flying CubeSat. Two 1.5U vehicles, AC7-B&C, built under NASA's Optical Communications and Sensors Demonstration (OCSD) program were launched in November 2017 and subsequently placed into a 450-km, 51.6° inc. circular orbit. Pseudorandom data streams using on-off key (OOK) modulation were transmitted from AC-7B to a 40 cm aperture telescope located at sea level in El Segundo, CA. At 200 Mbps, without forward error correction (FEC), we achieved a 115-second link that was ~78% error free, with the remaining portion exhibiting an error rate below 1E-5. At the time of the engagement, the 1064-nm laser transmitter was operating at 2 W (half capacity) with a full width half maximum (FWHM) beam divergence of ~1 mrad, which was approximately double the anticipated pointing accuracy of the vehicle.
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http://dx.doi.org/10.1364/OE.27.024382DOI Listing
August 2019

Depression, post-traumatic stress disorder, and dry eye syndrome: a study utilizing the national United States Veterans Affairs administrative database.

Am J Ophthalmol 2012 Aug 27;154(2):340-346.e2. Epub 2012 Apr 27.

Miami Veterans Administration Medical Center, Miami, Florida; Bascom Palmer Eye Institute, University of Miami, Miami, FL 33136, USA.

Purpose: To study the scope of dry eye syndrome (DES) in veterans on a national level and to evaluate the relationship between psychiatric diagnoses and DES.

Design: Case-control study.

Methods:

Setting: Patients were seen in a Veterans Affairs (VA) eye clinic between 2006 and 2011.

Patient Population: Patients were divided into cases and controls with regard to their dry eye status (cases = ICD-9 code for DES plus dry eye therapy; controls = patients without ICD-9 code plus no therapy).

Main Outcome Measures: The prevalence of DES and the influence of psychiatric diagnoses on the risk of DES.

Results: A total of 2 454 458 patients were identified as either a dry eye case (n = 462 641) or control (n = 1 991 817). Overall, 19% of male patients and 22% of female patients had a diagnosis of DES, with female sex imparting an increased risk of DES at each decade compared to male sex (odds ratio [OR] 1.22-2.09). Several conditions were found to increase DES risk, including post-traumatic stress disorder (OR 1.92, 95% CI 1.91-1.94) and depression (OR 1.92, 95% CI 1.91-1.94) (analyses adjusted for sex and age). The use of several systemic medications was likewise associated with an increased risk of DES, including antidepressant medications (OR 1.97, 95% CI 1.79-2.17) and antianxiety medication (OR 1.74, 95% CI 1.58-1.91). Multivariate analysis (adjusted for age and sex) revealed that for psychiatric diagnoses, both the use of medication and the diagnosis remained significant risk factors when considered concomitantly, although the magnitude of each association decreased.

Conclusions: DES is a disease associated with depression and post-traumatic stress disorder, and is prevalent among male and female veterans receiving eye care services. The association could be driven by underlying disease physiology or medications used to treat psychiatric conditions. Regardless of the causal link, this suggests that individuals with a known psychiatric diagnosis should be questioned about dry eye symptoms and, if applicable, referred to an eye care physician.
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http://dx.doi.org/10.1016/j.ajo.2012.02.009DOI Listing
August 2012
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