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The inverted coaxial point contact high purity germanium (ICPC HPGe) detector exhibits the advantages of large volume, low depletion voltage, small capacitance, and excellent pulse shape discrimination (PSD) capability. An ICPC detector prototype with 0.9 pF capacitance was successfully fabricated and tested in this study using two different front-end electronics. The detector weighted approximately 1.5 kg and the depletion voltage was only 1800 V. The optimized operating voltage was found to be 2500 V and the leakage current was 7 pA. The detector was first connected to a homemade JFET based front-end with a pulsed reset design to minimize parallel noise. An energy resolution of 1.72 keV (full width at half maximum) was achieved at 1332 keV, demonstrating the good charge collection efficiency of the detector. An RC feedback front-end circuit was employed to test the PSD properties using a 228Th source. The PSD capability is similar to that of typical broad energy or point contact HPGe detectors, but is notably improved when the charge trapping is corrected using the drift time. [ABSTRACT FROM AUTHOR]

What is the effect of micro-RNA (miR)-21-5p-loaded bone marrow mesenchymal stem cell-derived exosomes (miR-21-Exo) on autoimmune premature ovarian insufficiency (POI)? The Cell Counting Kit 8 (CCK8) assay, fluorescence-activated cell sorting, western blotting, quantitative reverse transcriptase (qRT)-PCR and enzyme-linked immunosorbent assay (ELISA) verified the effect of miR-21-Exo on interferon-γ (IFN-γ)-induced KGN cells. qRT-PCR, western blotting and dual-luciferase reporter gene assays verified that miR-21-Exo mediated Msh homeobox 1 (MSX1) regulation of the Notch signalling pathway and that miR-21 interacted directly with MSX1. The effects of miR-21-Exo on the ovaries were verified by monitoring of the oestrous cycle, haematoxylin and eosin staining, follicle counts, ELISA, immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), western blotting and qRT-PCR. The results showed that miR-21-Exo promoted IFN-γ-induced KGN cell proliferation and hormone synthesis, and inhibited apoptosis. Using dual-luciferase reporter gene assays, miR-21 and MSX1 were shown to have direct interactions. Moreover, the findings elucidated that miR-21-Exo inhibited cell apoptosis and promoted hormone synthesis by mediating MSX1 to regulate the Notch signalling pathway. miR-21-Exo restored the ovarian structure in a mouse model of autoimmune POI, promoted endocrine function and proliferation, and inhibited apoptosis and inflammation in vivo. This study demonstrates that miR-21-Exo regulates the MSX1-mediated Notch signalling pathway to inhibit granulosa cell apoptosis and improve hormone synthesis function, providing insight into a potential mechanism of molecular therapy for the treatment of autoimmune POI. [Display omitted] [ABSTRACT FROM AUTHOR]