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2D materials, specifically MoS2 semiconductors, have received tremendous attention for photo‐sensing applications due to their tunable bandgap and low noise levels. A unique photodetector using multilayer MoS2 as the semiconductor channel, in which the gate electrode of the device is permanently connected to the grounded source electrode to introduce rectification, is reported. The proposed grounded‐gate photodiode exhibits high photoresponsivity of 1.031 A W−1, excellent photodetectivity (>6 × 1010 jones), and highly stable rise/fall time response (100–200 ms) under illumination of visible light (at the wavelengths of 405, 532, and 638 nm). Numerical device simulations using quantum transport methods and photoconductive effects are used to explain the device operation. It is also suggested that the gate metal work function can be carefully chosen to increase the sensitivity of the grounded‐gate photodetector by suppressing the dark current. The grounded‐gate device proposed, owing to the properties of rectifying behavior, low contact resistance, consistent photoresponsivity, and linear sensitivity, provides a new platform for next‐generation applications in the field of electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

Partially purified paeoniflorin (PF), a new cosmetic ingredient from roots of Paeoniae lactiflora, has been developed. Its paeoniflorin content is about 64%, far higher than that of conventional, cosmetic-grade peony root extracts (approximately 10%). In this report, we studied the effects of PF on UV-induced DNA damage in both cultured human keratinocytes and hairless mouse skin. We also investigated the anti-wrinkle effects of PF-containing cosmetic preparations on human skin. From the in vitro and in vivo comet assay, it was revealed that PF protected cells from DNA damage induced by ultraviolet B (UVB) irradiation in both cultured normal human keratinocytes (19.4% decrease at 0.001%) and hairless mouse skin keratinocytes (41% decrease at 0.01%). An eight-week clinical trial using 0.5% PF-containing formulation with 20 volunteers resulted in a statistically significant reduction in facial wrinkles (p < 0.05). These results suggest that the partially purified paeoniflorin has potent anti-aging and anti-wrinkle activities and should be a useful ingredient for these purposes.