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The structure of glasses in the systems (100 - x)B2O3-xPbF2 (x = 30, 40, and 50) and 50B2O3-(50 - x)PbO-xPbF2 (x = 5, 10, 15, 20, 25, 30, 35, 40, and 45) has been studied by solid state NMR and EPR spectroscopies. On the basis of 11B and 19F high resolution solid state NMR as well as on 11B/19F double resonance results, we develop a quantitative structural description on the atomic scale. 19F NMR results indicate a systematic dependence of the fluoride speciation on PbF2 content: At low x-values, F- ions are predominantly found on BO3/2F- units, whereas, at higher x-values, fluoride tends to be sequestrated into amorphous domains rich in PbF2. In addition, both pulsed EPR studies of Yb3+ doped glasses and photophysical studies of Eu3+ doped samples indicate a mixed fluoride/borate coordination of the rare-earth ions and the absence of nanophase segregation effects. [ABSTRACT FROM AUTHOR]

Encapsulating nanomaterials in carbon is one of the main ways to increase the cathode stability, but it is difficult to simultaneously optimize the rate capacity and enhance durability derived from the insufficient ion transport channels and deficient ion adsorption sites that constipate the ion transport and pseudocapacitive reaction. Herein, we develop the ligand-confined growth strategy to encapsulate the nano-Na 3 V 2 (PO 4 ) 3 cathode material in various carbon channels (microporous, mesoporous, and macroporous) to discriminate the optimal carbon channels for synchronously improving rate capacity and holding the high-rate cycle stability. Benefiting from the unobstructed ion/charge transport channels and flexible maskant created by the interconnected mesoporous carbon channels, the prepared Na 3 V 2 (PO 4 ) 3 nanoparticles confined in mesoporous carbon channel (Mes-NVP/C) achieve a discharge-specific capacity of 70 mAh g -1 even at the ultrahigh rate of 100 C, higher than those of the Na 3 V 2 (PO 4 ) 3 nanoparticles confined in microporous and macroporous carbon channel (Micr-NVP/C and Macr-NVP/C), respectively. Significantly, the capacity retention rate of Mes-NVP/C after 5000 cycles at 20 C is as high as 90.48%, exceeding most of the reported work. These findings hold great promise for traditional cathode materials to synergistically realize fast charging ability and long cycle life.

This study applies in situ production of hypochlorous acid (HOCl) to improve the therapeutic efficacy of platinum drugs. The phagocytic enzyme myeloperoxidase (MPO) is coated with two functional polyphenol derivatives (platinum prodrug polyphenols and PEG polyphenols) and ferric ion by metal phenolic coordination, which can shield MPO from degradation by other compounds in the blood. Moreover, the platinum prodrug can be reduced to cisplatin in cells and produce hydrogen peroxide (H 2 O 2 ). The MPO catalyzes the conversion of H 2 O 2 to HOCl in the intercellular environment. The as-prepared MPO Pt PEG nanoparticles (MPP NPs) can be employed as a reactive oxygen species cascade bioreaction to enhance platinum drug therapy. The MPP NPs show prolonged blood circulation and high tumor accumulation as evidenced by 89 Zr-based positron emission tomography imaging. The MPP NPs effectively inhibit tumor growth in vivo. As a first-in-class platform to harness the highly toxic HOCl in nanomedicine for cancer therapy, this strategy may open doors for further development of progressive therapeutic systems.

Messenger RNA plays a pivotal role in regulating cellular activities. The expression dynamics of specific mRNA contains substantial information on the intracellular milieu. Unlike the imaging of stationary mRNAs, real-time intracellular imaging of the dynamics of mRNA expression is of great value for investigating mRNA biology and exploring specific cellular cascades. In addition to advanced imaging methods, timely extracellular stimulation is another key factor in regulating the mRNA expression repertoire. The integration of effective stimulation and imaging into a single robust system would significantly improve stimulation efficiency and imaging accuracy, producing fewer unwanted artifacts. In this study, we developed a multifunctional nanocomplex to enable self-activating and spatiotemporal imaging of the dynamics of mRNA sequential expression during the neural stem cell differentiation process. This nanocomplex showed improved enzymatic stability, fast recognition kinetics, and high specificity. With a mechanism regulated by endogenous cell machinery, this nanocomplex realized the successive stimulating motif release and the dynamic imaging of chronological mRNA expression during neural stem cell differentiation without the use of transgenetic manipulation. The dynamic imaging montage of mRNA expression ultimately facilitated genetic heterogeneity analysis. In vivo lateral ventricle injection of this nanocomplex enabled endogenous neural stem cell activation and labeling at their specific differentiation stages. This nanocomplex is highly amenable as an alternative tool to explore the dynamics of intricate mRNA activities in various physiological and pathological conditions.

We show that simply designed amphiphilic 4-helix bundle peptides can be utilized to vectorially orient a linearly extended donor-bridge-acceptor (D-br-A) electron transfer (ET) chromophore within its core. The bundle's interior is shown to provide a unique solvation environment for the D-br-A assembly not accessible in conventional solvents and thereby control the magnitudes of both light-induced ET and thermal charge recombination rate constants. The amphiphilicity of the bundle's exterior was employed to vectorially orient the peptide-chromophore complex at a liquid-gas interface, and its ends were tailored for subsequent covalent attachment to an inorganic surface, via a "directed assembly" approach. Structural data, combined with evaluation of the excited state dynamics exhibited by these peptide-chromophore complexes, demonstrate that densely packed, acentrically ordered 2-D monolayer ensembles of such complexes at high in-plane chromophore densities approaching 1/200 Å(2) offer unique potential as active layers in binary heterojunction photovoltaic devices.

By taking advantage of the features of ferrocene as a redox-active electron donor unit and perylene diimide as a fluorescence unit, a new redox fluorescence switch can be constructed on the basis of this triad.