Beta-phase gallium oxide (beta-Ga2O3) has exceptional electronic properties with vast potential in power and radio frequency electronics. Despite the excellent demonstrations of high-performance unipolar devices, the ...
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Beta-phase gallium oxide (beta-Ga2O3) has exceptional electronic properties with vast potential in power and radio frequency electronics. Despite the excellent demonstrations of high-performance unipolar devices, the lack of effective p-type dopants in beta-Ga2O3 has hindered the further development of Ga2O3-based bipolar devices. In this work, we applied the semiconductor grafting approach and fabricated monocrystalline Si/beta-Ga(2)O(3)p-n heterojunctions, of which the characteristics were systematically studied. The heterojunctions demonstrated a diode rectification over 1.3 x 10(7) at +/- 2 V with a diode ideality factor of 1.13. Furthermore, capacitance-voltage (C-V) measurement showed frequency dispersion-free characteristics from 10 to 900 kHz. The interface defect density (D-it) was calculated as 1-3 x 10(12)/cm(2) eV. Scanning transmission electron microscopy (STEM) and x-ray photoelectron spectroscopy (XPS) revealed that an ultrathin oxygen-rich layer existed on the Ga2O3 surface and later formed an ultrathin interfacial layer after bonding with Si. It is speculated that the excessive oxygen at the Ga2O3 surface enhanced the passivation of the Si dangling bonds and thus reduced D-it. This work improved our understanding of interface properties of the semiconductor grafting approach, providing useful guidance on the future development of Si/Ga2O3 heterojunction devices.
Objective: To investigate the placental morphology alterations and identify the clinical characteristics of women with polycystic ovary syndrome (PCOS) and their newborns. Pregnant women with PCOS (n = 12) and pregnan...
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Objective: To investigate the placental morphology alterations and identify the clinical characteristics of women with polycystic ovary syndrome (PCOS) and their newborns. Pregnant women with PCOS (n = 12) and pregnant women without PCOS (n = 11) were recruited. Then, the placenta, maternal blood and cord blood were collected after delivery. Design: Clinical observational study. Setting: Not applicable. Patient(s): In the present study, pregnant women with PCOS and healthy pregnant women were recruited from the clinic of the Department of Obstetrics and Gynecology, First Affiliated Hospital, Heilongjiang University of Chinese Medicine, China, between February 2015 and October 2015. Intervention(s): None. Main Outcome Measure(s): A proteomic analysis was performed on the placenta in women with PCOS and healthy women. Result(s): The maternal testosterone, androstenedione, dehydroepiandrosterone sulfate, free androgen index, cholesterol, apolipoprotein B, and apolipoprotein B/apolipoprotein A-I levels were significantly higher in the PCOS group than in the control group, and the offspring in the PCOS group had higher dehydroepiandrosterone sulfate, high-density lipoprotein, and cholesterol levels, when compared with the control group. The placenta in the PCOS group demonstrated infarction, calcification, and a greater intervillous space, when compared with the control group. A higher level of estrogen receptor-beta protein was observed in the placenta of women with PCOS, when compared with women without PCOS. A total of 258 proteins in the placenta were identified to be significantly different, when the PCOS and control groups were compared, and fibronectin 1 exhibited the closest relationship with other differential proteins. Conclusion(s): The overexposure to hyperandrogenism and hyperlipidemia affects the functions of the placenta, which are associated with the development of metabolic disorders in newborns. ((C) 2020 by American Society for Reproductive Medicine.)
HIV-1 transmembrane protein gp41 plays a crucial role by forming a stable six-helix bundle during HIV entry. Due to highly conserved sequence of gp41, the development of an effective and safe small-molecule compound t...
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HIV-1 transmembrane protein gp41 plays a crucial role by forming a stable six-helix bundle during HIV entry. Due to highly conserved sequence of gp41, the development of an effective and safe small-molecule compound targeting gp41 is a good choice. Currently, natural polyanionic ingredients with anti-HIV activities have aroused concern. Here, we first discovered that a glycosylated dihydrochalcone, trilobatin, exhibited broad anti-HIV-1 activity and low cytotoxicity in vitro. Site-directed mutagenesis analysis suggested that the hydrophobic residue (1564) located in gp41 pocket-forming site is pivotal for anti-HIV activity of trilobatin. Furthermore, trilobatin displayed synergistic anti-HIV activities combined with other antiretroviral agents. Trilobatin has a good potential to be developed as a small-molecule HIV-1 entry inhibitor for clinical combination therapy.
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