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Amelotin (AMTN) as a matrix protein exerts a direct effect on biomineralization by modulating apatite (HAP) formation during the dental enamel maturation stage through the specific interaction of a potentially phosphorylated Ser-Ser-Glu-Glu-Leu (SSEEL) peptide fragment with calcium phosphate (Ca-P) surfaces. However, the roles of (non)phosphorylation of this evolutionarily conserved subdomain within AMTN remain poorly understood. Here, we show, by time-resolved atomic force microscopy (AFM) imaging of in situ HAP crystallization via the HPO42--rich amorphous calcium phosphate (acidic ACP), the on/off switching of the phase transformation process through a nonphosphorylation-to-phosphorylation transition of the SSEEL motif. Using high-resolution transmission electron microscopy (HRTEM), we observed that the acidic ACP phase is stabilized by the phosphorylated SSEEL motif, delaying its transformation to HAP, whereas the nonphosphorylated counterpart promotes HAP formation by accelerating the dissolution-recrystallization of the acidic ACP substrate. Dynamic force spectroscopy measurements demonstrate greater binding energies of nonphosphorylated SSEEL to the acidic ACP substrate by the formation of molecular peptide-ACP bonding, explaining the enhanced dissolution of the acidic ACP substrate by stronger complexion with surface Ca2+ ions. Our findings demonstrate direct evidence for the switching role of (non)phosphorylation of an evolutionarily conserved subdomain within AMTN in controlling the phase transition of growing enamel and designing tissue regeneration biomaterials.Hierarchically porous materials have attracted great attention because of their potential applications in the fields of adsorption, catalysis, and biomedical systems. The art of manipulating different templates that are used for pore construction is the key to fabricating desired hierarchically porous structures. In this feature article, the polyelectrolyte-surfactant mesomorphous complex templating (PSMCT) approach, which was first developed by our group, is elaborated on. During the organic-inorganic self-assembly, the mesomorphous complex of the polyelectrolyte and oppositely charged surfactants would undergo in situ phase separation, which is the key to fabricating hierarchically porous materials. The recent progress in the utilization of the PSMCT method for the synthesis of hierarchically porous materials with tunable morphologies, mesophases, pore structures, and compositions is reviewed. Meanwhile, the functions of the hierarchically porous materials synthesized by the PSMCT method and their applications in adsorption, catalysis, drug delivery, and nanocasting are also briefly summarized.Density functional theory (DFT) study of ozone adsorption on dehydrated nanocrystalline TiO2 is presented. Singlet and triplet binding modes of ozone to the oxide's titanium cations are considered. In both the modes, monodentate and bidentate ozone complexes are formed. According to DFT, the triplet monodentates are the most stable species. The formation of monodentate ozone adsorption complexes is in-line with an earlier interpretation of infrared (IR) spectroscopic data on ozone adsorption on an anatase surface. However, the computed difference in the fundamental vibrational frequencies (ν1 - ν3) of ozone in the triplet monodentates is significantly larger than the corresponding IR value. This discrepancy is resolved by demonstrating that the triplet monodentates readily decompose, realizing molecular oxygen that is consistent with published experimental data. The predicted energy barrier of the dissociative adsorption is less than 2 kcal/mol. In contrast, the computed difference in the fundamental vibrational frequencies (ν1 - ν3) of adsorbed ozone in the singlet bidentates perfectly agrees with the experiment.The encapsulation of catalytically active noble metal nanoparticles (NM NPs) into metal-organic frameworks (MOFs) represents an effective strategy for enhancing their catalytic performance. Despite a myriad of reports on the nanocomposites consisting of NM NPs and MOFs, it remains challenging to develop a sustainable and convenient method for realizing confined integration of NM NPs within a porous and hollow zinc-based MOF. Herein, a simple and well-designed approach is reported to the fabrication of Pd@ZIF-8 hollow microspheres with a number of Pd nanoparticles immobilized on the inner surface. SB505124 TGF-beta inhibitor This method capitalized on the use of polyvinylpyrrolidone (PVP)-stabilized polystyrene (PS) microspheres as templates, to harness the dual functions of PVP for reducing PdCl2 to generate Pd NPs and coordinating with zinc ions to grow ZIF-8 shells. Consequently, it avoids the complicated protocols involving surface treatment of template microspheres that conventionally adopts hazardous or costly agents. The obtained Pd@ZIF-8 hollow microspheres exhibit outstanding catalytic activity, size selectivity, and stability in the hydrogenation of alkenes. This study presents both the advances in the green synthesis and great potential of Pd@ZIF-8 hollow microspheres for catalytic applications.Silicon anodes have attracted much attention owing to their high theoretical capacity. Nonetheless, an inevitable and enormous volumetric expansion of silicon in the lithiated state restrained the development of the silicon anode for lithium-ion batteries. Fortunately, the utilization of the high-performance binder is a promising and effective way to overcome such obstacles. Herein, a polymer of intrinsic microporosity (PIM) is applied as the binder for the silicon anode, which is composed of a rigid polymer backbone, an intrinsic porous structure, and active carboxyl groups (PIM-COOH). Compared to the traditional binder, both the long-term stability and rate performance of the electrode using PIM-COOH as the binder are significantly improved. The mechanism responsible for the enhanced performance is investigated. The PIM-COOH binder provides stronger adhesion toward the current collector than the conventional binders. The unique rigid polymer backbone and porous structure of the PIM-COOH binder enable a good capability to withstand the volume change and external stress generated by the Si anode.