This paper analytically investigates a bit error rate (BER) performance of radio over free space optical (FSO) systems considering laser phase noise under Gamma-Gamma turbulence channels. An external modulation using a dual drive Mach-Zehnder modulator (DD-MZM) and a phase shifter is employed because a DD-MZM is robust against a laser chirp and provides high spectral efficiency. We derive a closed form average BER as a function of different turbulence strengths and laser diode (LD) linewidth, and investigate its analytical behavior under practical scenario. As a result, for a given average SNR with normalized perturbation, it is shown that the difference of average BER corresponding to two LDs (with linewidth of 624 MHz and 10 MHz) under weak turbulence is almost 3 times larger than that under strong turbulence.
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http://dx.doi.org/10.1364/oe.17.004479 | DOI Listing |
Sci Rep
December 2024
Kahn Sagol Maccabi Research & Innovation Center, Maccabi Healthcare Services, Tel Aviv, Israel.
Identifying which patients should undergo serologic screening for celiac disease (CD) may help diagnose patients who otherwise often experience diagnostic delays or remain undiagnosed. Using anonymized outpatient data from the electronic medical records of Maccabi Healthcare Services, we developed and evaluated five machine learning models to classify patients as at-risk for CD autoimmunity prior to first documented diagnosis or positive serum tissue transglutaminase (tTG-IgA). A train set of highly seropositive (tTG-IgA > 10X ULN) cases (n = 677) with likely CD and controls (n = 176,293) with no evidence of CD autoimmunity was used for model development.
View Article and Find Full Text PDFJ Neuroendocrinol
December 2024
Department of Poultry Science, University of Arkansas, Fayetteville, Arkansas, USA.
Poultry production is confronting real challenges, including a lofty projected high demand for animal proteins to feed the future, and the need to adapt to planetary boundaries (global warming) with limited natural resources (land, energy, water). Among the most challenging stressors to poultry production sustainability are heat stress (HS) and water uncertainty, that need extensive fundamental and applied research to identify effective strategies. In that regard, our group has recently developed a high-water-efficient broiler (meat-type) chicken line using water conversion ratio (WCR) as a phenotypic trait and defined the hypothalamic molecular mechanisms controlling drinking water under heat stress conditions.
View Article and Find Full Text PDFSince visible light communication (VLC) uses light-emitting diode (LED) as transmitters, it has dual functions of illumination and communication. To meet flexible lighting and energy-saving needs, we propose a novel, to the best of our knowledge, dimming control scheme for spectrally efficient clipping-free multilayer optical orthogonal frequency division multiplexing (CFMO-OFDM)-based VLC systems. In order to achieve high dynamic-range dimming control for LEDs, the time-domain CFMO-OFDM signals are first grouped based on frequency-domain subcarrier distribution.
View Article and Find Full Text PDFJ Shoulder Elbow Surg
December 2024
Department of Orthopaedics and Rehabilitation, Oregon Health & Science University, Portland, OR, USA. Electronic address:
Background: The Centers for Medicare & Medicaid Services (CMS) implemented the Bundled Payments for Care Improvement Advanced (BPCIA) Model that covers 90-day care episodes after select orthopedic procedures including anatomic or reverse ball-and-socket total shoulder arthroplasty (TSA/rTSA). This study investigated whether patients undergoing TSA/rTSA for non-degenerative processes incur higher costs than patients undergoing arthroplasty for degenerative processes.
Methods: A retrospective review was conducted of all patients at a single academic medical center enrolled in the BPCIA model for TSA/rTSA from October 1, 2018, through December 31, 2022.
Sensors (Basel)
December 2024
School of Computing, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si 13120, Republic of Korea.
In the dynamic landscape of the tech industry, the escalating requirement for swift and secure data transmission has catalyzed innovation in integrated communication systems. Free-Space Optics (FSOs) has emerged as a promising contender in optical communications. While conventional optical fiber systems can achieve bit rates of up to 40 Gbps with proper design, they are limited primarily by electronics rather than semiconductor laser capabilities.
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