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Recently, hybrid supercapacitors (HSCs), which combine the use of battery and supercapacitor, have been extensively studied in order to satisfy increasing demands for large energy density and high power capability in energy-storage devices. For this purpose, the requirement for anode materials that provide enhanced charge storage sites (high capacity) and accommodate fast charge transport (high rate capability) has increased. Herein, therefore, a preparation of nanocomposite as anode material is presented and an advanced HSC using it is thoroughly analyzed. The HSC comprises a mesoporous Nb2O5/carbon (m-Nb2O5-C) nanocomposite anode synthesized by a simple one-pot method using a block copolymer assisted self-assembly and commercial activated carbon (MSP-20) cathode under organic electrolyte. The m-Nb2O5-C anode provides high specific capacity with outstanding rate performance and cyclability, mainly stemming from its enhanced pseudocapacitive behavior through introduction of a carbon-coated mesostructure within a voltage range from 3.0 to 1.1 V (vs Li/Li(+)). The HSC using the m-Nb2O5-C anode and MSP-20 cathode exhibits excellent energy and power densities (74 W h kg(-1) and 18,510 W kg(-1)), with advanced cycle life (capacity retention: ∼90% at 1000 mA g(-1) after 1000 cycles) within potential range from 1.0 to 3.5 V. In particular, we note that the highest power density (18,510 W kg(-1)) of HSC is achieved at 15 W h kg(-1), which is the highest level among similar HSC systems previously reported. With further study, the HSCs developed in this work could be a next-generation energy-storage device, bridging the performance gap between conventional batteries and supercapacitors.

Soma-germline interactions control fertility at many levels, including stem cell proliferation, meiosis and gametogenesis, yet the nature of these fundamental signaling mechanisms and their potential evolutionary conservation are incompletely understood. In C. elegans, a sperm-sensing mechanism regulates oocyte meiotic maturation and ovulation, tightly coordinating sperm availability and fertilization. Sperm release the major sperm protein (MSP) signal to trigger meiotic resumption (meiotic maturation) and to promote contraction of the follicle-like gonadal sheath cells that surround oocytes. Using genetic mosaic analysis, we show that all known MSP-dependent meiotic maturation events in the germline require Gα s -adenylate cyclase signaling in the gonadal sheath cells. We show that the MSP hormone promotes the sustained actomyosin-dependent cytoplasmic streaming that drives oocyte growth. Furthermore, we demonstrate that efficient oocyte production and cytoplasmic streaming require Gα s -adenylate cyclase signaling in the gonadal sheath cells, thereby providing a somatic mechanism that coordinates oocyte growth and meiotic maturation with sperm availability. We present genetic evidence that MSP and Gα s -adenylate cyclase signaling regulate oocyte growth and meiotic maturation in part by antagonizing gap-junctional communication between sheath cells and oocytes. In the absence of MSP or Gα s -adenylate cyclase signaling, MSP binding sites are enriched and appear clustered on sheath cells. We discuss these results in the context of a model in which the sheath cells function as the major initial sensor of MSP, potentially via multiple classes of G-protein-coupled receptors. Our findings highlight a remarkable similarity between the regulation of meiotic resumption by soma-germline interactions in C. elegans and mammals.

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