Nitrogen-Doped Seamless Activated Carbon Electrode with Excellent Durability for Electric Double Layer Capacitor

The electric double layer capacitor (EDLC) using a seamless activated carbon electrode shows an excellent durability against high voltage charging compared to the conventional activated carbon composite electrode. In this study, the authors focused on nitrogen-doping as a surface modification to further improve the electrochemical durability of the seamless electrode. The EDLC using the nitrogen-doped seamless activated carbon electrode achieved the volumetric capacitance of 18 F cm−3 (based on the galvanostatic method, 80 mA g−1, 0–2.5 V, 40 °C) and the capacitance retention of 83% after the float durability test (3.5 V, 70 °C, 100 h) using a typical propylene carbonate electrolyte. The volumetric capacitance is comparable to that (14 F cm−3) of the conventional activated carbon, such as YP50F, and the retention is much higher than that (76%) of the pristine seamless activated carbon. The authors concluded that the extremely excellent durability of the nitrogen-doped seamless activated carbon electrode is due to (i) the stable electric network arising from the binder-less monolithic structure and (ii) nitrogen surface functionalities that suppresses micropore blocking and internal resistance change caused by electrochemical decomposition deposits.This work is partially supported by JSPS KAKENHI Grant. No. JP17H03123 and Gunma University Element Functional Science Project in Japan

Progesterone Is a Sperm-Releasing Factor from the Sperm-Storage Tubules in Birds

Because of the presence of sperm-storage tubules (SST) in the utero-vaginal junction (UVJ) in the oviduct, once ejaculated sperm have entered the female reproductive tract, they can survive for a prolonged time in domestic birds, although the specific mechanisms involved in the sperm uptake into, maintenance within, and controlled release from the SST remain to be elucidated. In this report, we provide evidence that progesterone triggers the release of the resident sperm from the SST in the UVJ. The ultrastructural observation of the SST indicated that the resident sperm are released from the SST around 20 h after oviposition. When laying birds were injected with progesterone, most of the sperm were released from the SST within 1 h of injection. In situ hybridization analyses demonstrated the presence of the transcripts of membrane progestin receptor α in the UVJ, and the translated proteins were detected in the UVJ extracts by Western blotting. Moreover, the number of secretory granules in the SST epithelial cells fluctuates during the ovulatory cycle, and the progesterone administration mimics this phenomena. A binding assay using [(3)H]-progesterone indicated the presence of a high affinity, limited capacity, saturable and single binding site for [(3)H]-progesterone in the membrane fraction of the UVJ, and this receptor did not interact with the synthetic antiprogestin RU486. These results demonstrated for the first time that the progesterone stimulates the release of the resident sperm from the SST and that the release of the sperm might occur via membrane progestin receptor α-mediating signal transduction.autho