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.

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.

ObjectiveTo compare multi-detector computed tomography (MDCT) with cardiac catheterization and transthoracic echocardiography (TTE) in comprehensive evaluation of the global cardiovascular anatomy in patients with pulmonary atresia with ventricular septal defect (PA-VSD).MethodsThe clinical and imaging data of 116 patients with PA-VSD confirmed by surgery were reviewed. Using findings at surgery as the reference standard, data from MDCT, TTE and catheterization were reviewed for assessment of native pulmonary vasculature and intracardiac defects.ResultsMDCT was more accurate than catheterization and TTE in identification of native pulmonary arteries. MDCT is also the most accurate test for delineation of the major aortopulmonary collateral arteries. The inter-modality agreement for evaluation of overriding aorta and VSD were both excellent. In the subgroup with surgical correlation, excellent agreement was found between TTE and surgery, and substantial agreement was also found at MDCT.ConclusionMDCT can correctly delineate the native pulmonary vasculatures and intracardiac defects and may be a reliable method for noninvasive assessment of global cardiovascular abnormalities in patients with PA-VSD.

A 57-year-old man with a long history of frequent chest pain was admitted to our cardiac center. Four years ago, he underwent coronary artery bypass grafting (CABG) with the left internal mammary artery (LIMA) to the distal segment of the left anterior descending coronary artery (LAD) grafting for myocardial bridging (MB) in LAD despite having ␤-blockers and calcium channel blockers. However, the patient still had recurrent angina within 3 months after the operation. ECG showed negative T wave in leads V1 and V2. On echocardiography, left ventricular ejection fraction was 60% with normal regional wall motion. The repeat coronary angiography showed a MB in the proximal LAD about 3 cm in length with 90% systolic narrowing of the LAD, and the LIMA graft was totally occluded ( Figure 1A through 1C). The angiographic manifestation of MB was the same as that of the coronary angiography ( Figure 2A through 2B) before the previous CABG operation.Through a remedian sternotomy, a tight fibrous adhesion was dissected and the anterior wall of the heart was exposed. The location of the LAD was difficultly identified and was carefully confirmed by excising epicardial adipose tissue and epicardium. Surgical myotomy was performed during cardioplegic arrest under cardiopulmonary bypass. The proximal LAD was completely unroofed of MB to eliminate the phasic compression of the coronary vessel ( Figure 1D).The patient had an uneventful postoperative course and is asymptomatic at 22 months of follow-up. Four-months' follow-up catheterization was performed: No systolic narrowing of the LAD could be visualized ( Figure 1E).MB is a congenital anomaly, most common in the middle segment of the LAD, that may cause myocardial ischemia and infarction, cardiac arrhythmias, and sudden cardiac death. 1 The current gold standard for diagnosing MB is coronary angiography with the typical systolic compression of the epicardial coronary vessel (milking effect). Recent studies have shown that coronary narrowing by MB may not only occur in systole but also result in a delayed and incomplete vessel diameter gain during mid-to-late diastole, thereby affecting the predominant phase of the coronary perfusion. 2 In symptomatic MB that is unresponsive to medication, intracoronary stenting and surgical interventions may be adopted as an alternative treatment. However, stenting should not be recommended in MB because of the risk of stent thrombosis and restenosis. 3 Moreover, although CABG is also an effective treatment of MB and LIMA as the first choice of autogenous graft has the best long-term patency rate, the procedure cannot cure the MB and remains the possibility of graft restenosis and spasm resulting in recurrent angina. Surgical myotomy is a radical correction and suitable for every patient with persistent ischemic symptoms despite intensive medication. It can not only treat the physiological abnormality of MB, but also can correct the congenital anatomical defect 4 without the risk of graft restenosis and thrombosis. The key points during the int...

The objective of this study is to evaluate comprehensive performance of high modulus asphalt concrete (HMAC) and propose common values for establishing evaluation system. Three gradations with different modifiers were conducted to study the high and low temperature performance, shearing behavior, and water stability. The laboratory tests for HMAC included static and dynamic modulus tests, rutting test, uniaxial penetration test, bending test, and immersion Marshall test. Dynamic modulus test results showed that modifier can improve the static modulus and the improvements were remarkable at higher temperature. Moreover, modulus of HMAC-20 was better than those of HMAC-16 and HMAC-25. The results of performance test indicated that HMAC has good performance to resist high temperature rutting, and the resistances of the HMAC-20 and HMAC-25 against rutting were better than that of HMAC-16. Then, the common values of dynamic stability were recommended. Furthermore, common values of HMAC performance were established based on pavement performance tests.

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