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Piezoelectricity offers an electromechanical coupling that is widely utilized in transducer applications. There has been a consistent demand for transparent piezoelectric materials for optoelectrical applications. Therefore, despite the inherent tradeoff between the transparency and the piezoelectricity, numerous strategies have been explored to develop the transparent piezoelectric materials. Nonetheless, the most transparent piezoelectric materials developed to date is either a single crystal or materials that achieve transparency via hot-press sintering, limiting its industrial applicability. Therefore, we introduce a novel piezoelectric material that ensures transparency through co-doping and pressureless sintering of polycrystalline ceramics. In this study, we employed a compositional optimization approach to enhance the synergistic effect between the transparency and the piezoelectric properties of 0.71Pb(Mg1/3Nb2/3)O3–0.29PbTiO3 (PMN–0.29PT) ceramics. By utilizing the tape casting process for mass production and large-area manufacturing, our Pb0.913La0.0145Sm0.0145(Mg1/3Nb2/3)0.71Ti0.29O3 (TP2.9) ceramics exhibited over 60% transparency and large piezoelectric coefficient (d33) of 1104 pC/N. This material holds considerable promise for a wide range of industrial applications in both the optical and electronic domains.

The adult hippocampal neurogenesis plays a vital role in the function of the central nervous system (CNS), including memory consolidation, cognitive flexibility, emotional function, and social behavior. The deficiency of adult neural stem cells (aNSCs) in maintaining the quiescence and entering cell cycle, self-renewal and differentiation capacity is detrimental to the functional integrity of neurons and cognition of the adult brain. Histone acetyltransferase (HAT) and histone deacetylase (HDAC) have been shown to modulate brain functionality and are important for embryonic neurogenesis via regulation of gene transcription. We showed previously that Trrap, an adapter for several HAT complexes, is required for Sp1 transcriptional control of the microtubule dynamics in neuronal cells. Here, we find that Trrap deletion compromises self-renewal and differentiation of aNSCs in mice and in cultures. We find that the acetylation status of lysine residues K16, K19, K703 and K639 all fail to overcome Trrap-deficiency-incurred instability of Sp1, indicating a scaffold role of Trrap. Interestingly, the deacetylation of Sp1 at K639 and K703 greatly increases Sp1 binding to the promoter of target genes, which antagonizes Trrap binding, and thereby elevates Sp1 activity. However, only deacetylated K639 is refractory to Trrap deficiency and corrects the differentiation defects of Trrap-deleted aNSCs. We demonstrate that the acetylation pattern at K639 by HATs dictates the role of Sp1 in the regulation of adult neurogenesis.

The members of the phosphatidylinositol 3-kinase-related kinase (PIKK) family play vital roles in multiple biological processes, including DNA damage response, metabolism, cell growth, mRNA decay, and transcription. TRRAP, as the only member lacking the enzymatic activity in this family, is an adaptor protein for several histone acetyltransferase (HAT) complexes and a scaffold protein for multiple transcription factors. TRRAP has been demonstrated to regulate various cellular functions in cell cycle progression, cell stemness maintenance and differentiation, as well as neural homeostasis. TRRAP is known to be an important orchestrator of many molecular machineries in gene transcription by modulating the activity of some key transcription factors, including E2F1, c-Myc, p53, and recently, Sp1. This review summarizes the biological and biochemical studies on the action mode of TRRAP together with the transcription factors, focusing on how TRRAP-HAT mediates the transactivation of Sp1-governing biological processes, including neurodegeneration.

In this study, an acoustic emission (AE) sensor was fabricated using lead-free Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BZT–BCT) ceramics. The acoustic and electromechanical properties of the AE sensor were determined by the shapes of the piezoelectric ceramics. To optimize the AE sensor performance, the shapes of the ceramics were designed according to various diameter/thickness ratios (D/T) = 0.5, 1.0, 1.5, 2.0, 2.5, 3.0. The BZT–BCT ceramic with D/T = 1.0 exhibited excellent values of a piezoelectric charge coefficient (d33), piezoelectric voltage coefficient (g33), and electromechanical coupling factor (kp), which were 370 (pC/N), 11.3 (10−3 Vm/N), and 0.58, respectively. Optimum values of resonant frequency (fr) = 172.724 (kHz), anti-resonant frequency (fa) = 196.067 (kHz), and effective electromechanical coupling factor (keff) = 0.473 were obtained for the manufactured BZT–BCT ceramic with D/T = 1.0. The maximum sensitivity and frequency of the AE sensor made of the BZT–BCT ceramic with a D/T ratio of 1.0 were 65 dB and 30 kHz, respectively.