TianQin is a planned space-based gravitational wave (GW) observatory consisting of three Earth-orbiting satellites with an orbital radius of about $10^5 \, {\rm km}$. The satellites will form an equilateral triangle constellation the plane of which is nearly perpendicular to the ecliptic plane. TianQin aims to detect GWs between $10^{-4} \, {\rm Hz}$ and $1 \, {\rm Hz}$ that can be generated by a wide variety of important astrophysical and cosmological sources, including the inspiral of Galactic ultra-compact binaries, the inspiral of stellar-mass black hole binaries, extreme mass ratio inspirals, the merger of massive black hole binaries, and possibly the energetic processes in the very early universe and exotic sources such as cosmic strings. In order to start science operations around 2035, a roadmap called the 0123 plan is being used to bring the key technologies of TianQin to maturity, supported by the construction of a series of research facilities on the ground. Two major projects of the 0123 plan are being carried out. In this process, the team has created a new-generation $17 \, {\rm cm}$ single-body hollow corner-cube retro-reflector which was launched with the QueQiao satellite on 21 May 2018; a new laser-ranging station equipped with a $1.2 \, {\rm m}$ telescope has been constructed and the station has successfully ranged to all five retro-reflectors on the Moon; and the TianQin-1 experimental satellite was launched on 20 December 2019—the first-round result shows that the satellite has exceeded all of its mission requirements.

Background: Circulating asprosin is a newly discovered adipokine that triggers the release of hepatic glucose stores and increases appetite. Asprosin levels are elevated in adult obese men as well as in mice, and reductions in asprosin protect against the hyperinsulinism associated with metabolic syndrome in mice with diet-induced obesity, which indicates a potential therapeutic role of asprosin in obesity and type 2 diabetes. Objectives: Few data on asprosin in children are available, which is why this study aimed to assess concentrations of fasting asprosin, as well as its relationship to parameters of glucose and lipid metabolism, in children. Methods: Data on clinical and metabolic parameters were collected from 40 healthy normal-weight and 47 obese children. Circulating asprosin levels were measured using an ELISA. Results: The concentrations of fasting asprosin were lower in the obese children (9.24 ± 4.11 ng/mL) than in the normal-weight controls (12.33 ± 4.18 ng/mL, p < 0.001). When comparing the two groups by sex, both the boys and the girls showed similar trends. In within-group comparison, the asprosin levels were lower in boys than in girls only in the obese group (8.13 ± 4.10 vs. 10.61 ± 3.78 ng/mL, p = 0.013) but not in the control group. Interestingly, asprosin was correlated with ALT after adjusting for age and sex in all participants; in boys, asprosin was correlated with BMI, HOMA-IR, insulin, and HDL after adjusting for age. Conclusions: Concentrations of asprosin were significantly lower in obese children than in normal-weight children, and there was a gender difference in asprosin concentration. Our results suggest a complex role for asprosin in energy metabolism.

The TianQin-1 satellite (TQ-1), which is the first technology demonstration satellite for the TianQin project, was launched on

High-precision electrostatic accelerometers have achieved remarkable success in satellite Earth gravity field recovery missions. Ultralow-noise inertial sensors play important roles in space gravitational wave detection missions such as the Laser Interferometer Space Antenna (LISA) mission, and key technologies have been verified in the LISA Pathfinder mission. Meanwhile, at Huazhong University of Science and Technology (HUST, China), a space accelerometer and inertial sensor based on capacitive sensors and the electrostatic control technique have also been studied and developed independently for more than 16 years. In this paper, we review the operational principle, application, and requirements of the electrostatic accelerometer and inertial sensor in different space missions. The development and progress of a space electrostatic accelerometer at HUST, including ground investigation and space verification are presented.