JAXA and NICT have started the collaborative research for cislunar optical communications. NICT is responsible for research and development some of key technologies for cislunar optical communication systems utilizing GEO relay satellite. NICT has especially focused on research and development of a large-aperture optical antenna, high-sensitivity optical communication system applying adaptive optics and HDR method, which is based on binary phase shift keying scheme, onboard the GEO relay satellite. In this paper, we will present the overview of collaborative research and key technologies for cislunar optical communication systems. We will also describe the current status of our research and development activities.

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Aims Sodium—glucose cotransporter 2 inhibitor (SGLT2i) improves clinical outcomes in patients with heart failure (HF), but has limited evidence of SGLT2i use on early-phase acute coronary syndrome (ACS). We determined association of early SGLT2i use compared with either non-SGLT2i or dipeptidyl peptidase 4 inhibitor (DPP4i) in hospitalized patients with ACS. Methods and Results This retrospective cohort study that used the Japanese nationwide administrative claims database included patients hospitalized with ACS aged ≥ 20 years between April 2014 and March 2021. The primary outcome was a composite of all-cause mortality or HF/ACS rehospitalization. Using 1:1 propensity score matching, the association with outcomes of the early SGLT2i use (≤14 days after admission) compared with non-SGLT2i or DPP4i was determined according to the HF treatment. Among 388 185 patients included, 115 612 and 272 573 with and without severe HF, respectively. Compared to non-SGLT2i users, the SGLT2i users had a lower hazard ratio (HR) with the primary outcome (HR: 0.83, 95% confidence interval [CI]: 0.76–0.91, p < 0.001) in the severe HF group; however, there was no significant difference in the non-severe HF group (HR: 0.92, 95% CI: 0.82–1.03, p = 0.16). SGLT2i use showed a lower risk of the outcome in patients with severe HF and diabetes compared with DPP4i (HR: 0.83, 95% CI: 0.69–1.00, p = 0.049). Conclusion SGLT2i use in patients with early-phase ACS showed a lower risk of primary outcome in patients with severe HF but the effect was not apparent in patients without severe HF.

This paper describes experimental analysis of atmospheric channel model of Geostationary Earth Orbit (GEO) satellite-to-ground optical link by utilizing the Laser Utilizing Communication Systems (LUCAS) onboard the optical data relay GEO satellite. Our research work examines the effect of misalignment fading and various atmospheric turbulence conditions. These analytical results clarify that atmospheric channel model is well fitted to theoretical distributions with misalignment fading under various turbulence regimes. We also evaluate several atmospheric channel characteristics, including coherence time, power spectral density and probability of fade, in various turbulence conditions.