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The sigma-1 receptor (σ1R) is a unique intracellular protein. σ1R plays a major role in various pathological conditions in the central nervous system (CNS), implicated in several neuropsychiatric disorders. Imaging of σ1R in the brain using positron emission tomography (PET) could serve as a noninvasively tool for enhancing the understanding of the disease's pathophysiology. Moreover, σ1R PET tracers can be used for target validation and quantification in diagnosis. Herein, we describe the radiosynthesis, in vivo PET/CT imaging of novel σ1R 11C-labeled radioligands based on 6-hydroxypyridazinone, [11C]HCC0923 and [11C]HCC0929. Two radioligands have high affinities to σ1R, with good selectivity. In mice PET/CT imaging, both radioligands showed appropriate kinetics and distributions. Additionally, the specific interactions of two radioligands were reduced by compounds 13 and 15 (self-blocking). Of the two, [11C]HCC0929 was further investigated in positive ligands blocking studies, using classic σ1R agonist SA 4503 and σ1R antagonist PD 144418. Both σ1R ligands could extensively decreased the uptake of [11C]HCC0929 in mice brain. Besides, the biodistribution of major brain regions and organs of mice were determined in vivo. These studies demonstrated that two radioligands, especially [11C]HCC0929, possessed ideal imaging properties and might be valuable tools for non-invasive quantification of σ1R in brain. KEY WORDS: σ1R, PET, Brain imaging, 6-Hydroxypyridazinone, 11C-labeled radioligand

In this study, two randomly packed beds with small tube-to-particle diameter (D/d) ratios of D/d = 4 (PB-4) and D/d = 5 (PB-5) are constructed using the discrete element method (DEM). The pore-scale heat transfer characteristics of hydrogen flow at low pore Reynolds numbers (Rep

In HSCW (Hot Summer and Cold Winter) climate zone of China, the building heat load is usually less than the cooling load which caused the problem of thermal accumulation of underground soil to damaged the COP of the heat pump system. PV/T-GCHPs (Photovoltaic/photothermal - Ground-coupled heat pump system) is a system that realizes the complementary utilization of geothermal energy and solar energy to solve the problem. The experimental platform of the system was designed and built, and the effect of the temperature of the outlet water from the ground buried pipes on the photoelectric efficiency of the PV panel was analyzed through experiments and simulations under the heating conditions of the PV/T-GCHPs system, and the heating performance coefficients of PV/T-GCHPs and GCHPs were compared. The results show that the PV plate temperature reaches the lowest when the heat pump load is 75% and the circulating water flow is 0.28 kg/s, when the outlet temperature of buried pipe is 8℃. The maximum photoelectric efficiency increased by 6.4% under above conditions, the average heating performance coefficient of PV/T-GCHPs is increased by 2.2% compared with GCHPs. The daily average comprehensive efficiency is 63.32%, the maximum comprehensive efficiency of the system is 74.67%. The maximum heat collection efficiency of PV/T collector is 48.33%. This paper hopes to provide a theoretical basis for the promotion of PV/T-GCHPs in HSCW climate zone of China.