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Developing new materials for anhydrous proton conduction under high‐temperature conditions is significant and challenging. Herein, we create a series of highly crystalline covalent organic frameworks (COFs) via a pore engineering approach. We simultaneously engineer the pore geometry (generating concave dodecagonal nanopores) and pore surface (installing multiple functional groups such as −C=N−, −OH, −N=N− and −CF3) to improve the utilization efficiency and host–guest interaction of proton carriers, hence benefiting the enhancement of anhydrous proton conduction. Upon loading with H3PO4, COFs can realize a proton conductivity of 2.33×10−2 S cm−1 under anhydrous conditions, among the highest values of all COF materials. These materials demonstrate good stability and maintain high proton conductivity over a wide temperature range (80–160 °C). This work paves a new way for designing COFs for anhydrous proton conduction applications, which shows great potential as high‐temperature proton exchange membranes. [ABSTRACT FROM AUTHOR]

Author(s): David Z. Z. He (corresponding author) [1, 2]; Shuping Jia [1]; Peter Dallos [3] Sensory receptor cells of the mammalian cochlea are morphologically and functionally dichotomized. Inner hair cells [...]

Author(s): M. Charles Liberman [1, 2]; Jiangang Gao [2, 3]; David Z. Z. He [4]; Xudong Wu [3, 5]; Shuping Jia [4]; Jian Zuo (corresponding author) [3] Hearing sensitivity in [...]

The remarkable sensitivity and frequency selectivity of the mammalian cochlea is attributed to a unique amplification process that resides in outer hair cells (OHCs). Although the mammalian-specific somatic motility is considered a substrate of cochlear amplification, it has also been proposed that somatic motility in mammals simply acts as an operating-point adjustment for the ubiquitous stereocilia-based amplifier. To address this issue, we created a mouse model in which a mutation (Cl) was introduced into the OHC motor protein prestin, based on previous results in transfected cells. In Cl/Cl knockin mice, localization of Ci-prestin, as well as the length and number of OHCs, were all normal. In OHCs isolated from Cl/Cl mice, nonlinear capacitance and somatic motility were both shifted toward hyperpolarization, so that, compared with WT controls, the amplitude of cycle-by- cycle (alternating, or AC) somatic motility remained the same, but the unidirectional (DC) component reversed polarity near the OHC's presumed in vivo resting membrane potential. No physiological defects in cochlear sensitivity or frequency selectivity were detected in Cl/Cl or C1/+ mice. Hence, our results do not support the idea that OHC somatic motility adjusts the operating point of a stereocilia-based amplifier. However, they are consistent with the notion that the AC component of OHC somatic motility plays a dominant role in mammalian cochlear amplification. [ABSTRACT FROM AUTHOR]

Two C 2 H 6 -selective metal-organic framework (MOF) adsorbents with ultrahigh stability, high surface areas, and suitable pore size have been designed and synthesized for one-step separation of ethane/ethylene (C 2 H 6 /C 2 H 4 ) under humid conditions to produce polymer-grade pure C 2 H 4 . Experimental results reveal that these two MOFs not only adsorb a high amount of C 2 H 6 but also display good C 2 H 6 /C 2 H 4 selectivity verified by fixed bed column breakthrough experiments. Most importantly, the good water stability and hydrophobic pore environments make these two MOFs capable of efficiently separating C 2 H 6 /C 2 H 4 under humid conditions, exhibiting the benchmark performance among all reported adsorbents for separation of C 2 H 6 /C 2 H 4 under humid conditions. Moreover, the affinity sites and their static adsorption energies were successfully revealed by single crystal data and computation studies. Adsorbents described in this work can be used to address major chemical industrial challenges., (© 2022 Wiley-VCH GmbH.)

Cochlear hair cells transduce mechanical stimuli into electrical activity. The site of hair cell transduction is the hair bundle, an array of stereocilia with different height arranged in a staircase. Tip links connect the apex of each stereocilium to the side of its taller neighbor. The hair bundle and tip links of hair cells are susceptible to acoustic trauma and ototoxic drugs. It has been shown that hair cells in lower vertebrates and in the mammalian vestibular system may survive bundle loss and undergo self-repair of the stereocilia. Our goals were to determine whether cochlear hair cells could survive the trauma and whether the tip link and/or the hair bundle could be regenerated. We simulated the acoustic trauma-induced tip link damage or stereociliary loss by disrupting tip links or ablating the hair bundles in the cultured organ of Corti from neonatal gerbils. Hair-cell fate and stereociliary morphology and function were examined using confocal and scanning electron microscopies and electrophysiology. Most bundleless hair cells survived and developed for approximately 2 weeks. However, no spontaneous hair-bundle regeneration was observed. When tip links were ruptured, repair of tip links and restoration of mechanotransduction were observed in <24 h. Our study suggests that the dynamic nature of the hair cell's transduction apparatus is retained despite the fact that regeneration of the hair bundle is lost in mammalian cochlear hair cells.