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Background Heart rate variability (HRV) has been investigated previously in autonomic nervous system-related clinical settings. In these settings, HRV is determined by the time-series heartbeat peak-to-peak intervals using electrocardiography (ECG). To reduce patient discomfort, we designed a Doppler radar-based autonomic nervous activity monitoring system (ANMS) that allows cardiopulmonary monitoring without using ECG electrodes or spirometry monitoring. Case summary Using our non-contact ANMS, we observed a bedridden 80-year-old female patient with terminal phase sepsis developed the daytime Cheyne-Stokes respiration (CSR) associated with the attenuation of the low frequency (LF) and high frequency (HF) of HRV components 20 days prior to her death. The patient developed a marked linear decrease in the LF and the HF of HRV components for over 3 days in a row. Furthermore, after the decrease both the LF and the HF showed low and linear values. Around the intersection of the two lines, the decreasing LF and HF lines and the constant LF and HF lines, the ANMS automatically detected the daytime CSR pathogenesis. The attenuation rate of HF (1340 ms2/day) was higher than that of LF (956 ms2/day). Heart rate increased by ∼10 b.p.m. during these 3 days. Discussion We detected CSR-associated LF and HF attenuation in a patient with terminal phase sepsis using our ANMS. The proposed system without lead appears promising for future applications in clinical settings, such as remote cardiac monitoring of patients with heart failure at home or in long-term acute care facilities.

There have been many developments in Light Detection And Ranging (LiDAR) sensors used in Autonomous Driving (AD) and Advanced Driver Assistance Systems (ADAS) to measure the precise distance to an object, recognize the shape of an intersection, and classify road types. These LiDAR sensors can achieve fantastic results day and night without any loss of performance. In the past, Time-Correlated Single Photon Counting (TCSPC) and complete digital signal processing (DSP) have been used in to achieve a 100m range Time-of-Flight (ToF) sensor [1]. Background (BG) noise-rejection techniques [2] have been used to improve the signal-to-noise ratio (SNR), leading to detection of objects at a 6km range. Single Photon Avalanche Diode (SPAD)-based architectures implement per-pixel level histogramming, Time-to-Digital Conversion (TDC) and signal processing [3], [4]. Another ToF sensor has been shown that enables significantly higher resolution, $1200 \times 900$ pixels [5]. With the emerging need for a highresolution solid-state LiDAR using a scanning 2D-SPAD array [6], we report a SPAD direct Time-of-Flight (dToF) depth sensor [1] –[5] to realize long-distance 300m range and high resolution over an automotive-grade temperature range of -40 to $125 ^{\circ}{C}$. This microelectromechanical systems (MEMS)-based SPAD LiDAR can measure over ranges up to 150m with 0.1% accuracy for a 10%-reflectivity target and 200m with 0.1% accuracy for a 95%-reflectivity target. This paper presents a back-illuminated stacked SPAD dToF depth sensor deployed with passive quenching and recharge (PQR) frontend circuitry, TCSPC, and on-chip DSP. Under 117klux sunlight conditions, the MEMS-based SPAD LiDAR measures distances up to 200m with $168 \times 63$ resolution at 20 frames/s.

A state of the art Back Illuminated (BI) Single Photon Avalanche Diode (SPAD) array sensor realized via a 90nm CMOS compatible process on a 300 mm silicon platform is reported in the following. The array consists of 10 μm pixels, each using a 7μm thick silicon active layer, which allows to extend the device's optical sensitivity up to the Near-Infrared (NIR) spectrum. Furthermore, buried metal Full Trench Isolation (FTI) was employed to suppress crosstalk (X-talk), a critical feature in a device sensitive enough to be triggered by a single electro-luminescence photon emitted by a neighboring pixel. Finally, in order to maximize the Fill Factor (F.F) and allow a BI structure, a Cu-Cu bonding process was carried out. Through process and device design optimization, not only a Photon Detection Efficiency (PDE) greater than 14% at λ= 940nm and low timing jitter were achieved, but also the best in class Dark Count Rate (DCR) as compared to previously reported SPAD sensors. These combined features pave the way towards efficient, eye-safe and cost-effective time of flight applications.

Downwind turbines have favorable characteristics such as effective energy capture in up-flow wind conditions over complex terrains. They also have reduced risk of severe accidents in the event of disruptions to electrical networks during strong storms due to the free-yaw effect of downwind turbines. These favorable characteristics have been confirmed by wind-towing tank experiments and computational fluid dynamics (CFD) simulations. However, these advantages have not been fully demonstrated in field experiments on actual wind farms. In this study—although the final objective was to demonstrate the potential advantages of downwind turbines through field experiments—field measurements were performed using a vertical-profiling light detection and ranging (LiDAR) system on a wind farm with downwind turbines installed in complex terrains. To deduce the horizontal wind speed, vertical-profiling LiDARs assume that the flow of air is uniform in space and time. However, in complex terrains and/or in wind farms where terrain and/or wind turbines cause flow distortion or disturbances in time and space, this assumption is not valid, resulting in erroneous wind speed estimates. The magnitude of this error was evaluated by comparing LiDAR measurements with those obtained using a cup anemometer mounted on a meteorological mast and detailed analysis of line-of-sight wind speeds. A factor that expresses the nonuniformity of wind speed in the horizontal measurement plane of vertical-profiling LiDAR is proposed to estimate the errors in wind speed. The possibility of measuring and evaluating various wind characteristics such as flow inclination angles, turbulence intensities, wind shear and wind veer, which are important for wind turbine design and for wind farm operation is demonstrated. However, additional evidence of actual field measurements on wind farms in areas with complex terrains is required in order to obtain more universal and objective evaluations.

The multicomponent system of [Fe(dpp)(2)][Ni(mnt)(2)](2).MeNO(2) (1; dpp = 2,6-bis(pyrazol-1-yl)pyridine and mnt = maleonitriledithiolate) was prepared by the reaction of [Fe(dpp)(2)](BF(4))(2) with (Bu(4)N)[Ni(mnt)(2)] in MeNO(2). Variable-temperature X-ray structural analyses, magnetic susceptibility, and heat capacity measurements confirmed that 1 undergoes multiple spin-state conversions in both the cationic and anionic components. The asymmetric unit in the crystal contains one [Fe(dpp)(2)](2+) cation, two [Ni(mnt)(2)](-) anions ([Ni1](-) and [Ni2](-)), and one solvent molecule. Magnetic susceptibility measurements revealed that a paramagnetic state in the high-temperature region (HT phase) was abruptly converted to a diamagnetic low-temperature (LT) phase below 180 K as the temperature was lowered from 270 K. As the temperature was raised from 125 to 270 K, successive phase transitions occurred to the HT phase via intermediate phases (IM1, IM2, and IM3) at 175.5, 186.5, 194.0, and 244.0 K, respectively. In the HT phase [Fe(dpp)(2)](2+) is in the high-spin state, and each [Ni1](-) and [Ni2](-) moiety is arranged in monomeric form with an S = (1)/(2) spin ground state. In the LT phase [Fe(dpp)(2)](2+) is in the low-spin state and the nickel moieties are dimerized and diamagnetic. In the IM1 and IM2 phases the iron(II) sites are partially in the HS state and both [Ni](-) moieties are dimeric, as suggested by (57)Fe Mossbauer measurements. In the IM3 phase, [Fe(dpp)(2)](2+) is in the HS state and the anions exist in both their monomeric ([Ni1](-)) and dimeric ([Ni2](-)) forms. Rapid thermal quenching from 300 to 5 K yielded a metastable HS phase, which relaxed to the LT phase via the IM1 phase as the temperature was raised to 150 K. A partial light induced spin transition on the iron site was observed at 5 K.