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Zinc manganese oxide (ZMO) system represents a notable family of mixed transition metal oxides (MTMOs) because of their superiority of the high theoretical capacity, adequacy of natural content, and low cost. However, the methods to match both the reliable synthesis and the designable construction of large-sized two-dimensional (2D) ZMO nanosheets are still considered grand challenges. Herein, we have successfully realized the preparation of 2D ZMO nanosheets with large lateral sizes up to ∼20 μm by simple pyrolysis of 2D metal-organic framework (MOF) nanosheets precursor. The growth mechanism of 2D MOF is proposed to be based on the lamellar micelles formed by polyvinyl pyrrolidone (PVP). The obtained 2D and porous ZMO nanosheets exhibit high specific capacity as well as good rate capability. More importantly, the as-prepared ZMO electrode shows a remarkable capacity increment upon cycling (from 832 mAh g-1 at the 2nd cycle to 1418 mAh g-1 at the 700th cycle, at 1 A g-1). Through simple adjustment of the calcination temperature, the valence state of Mn species in the yielding ZMO samples can be fine-tuned. Through systematic investigation towards these ZMOs containing different Mn species, the extra specific capacity is revealed to be chiefly on account of the arising of the valence state of Mn upon the cycling process. Moreover, it is disclosed that the higher-valent Mn the pristine ZMO contains, the more additional capacity it gains upon cycling. We believe that this work will inspire more detailed analysis on the relationship between the valence state of Mn and extra capacity.

A validated and sensitive 1H NMR method was developed for the qualitative and quantitative analysis of the two main components of “xinnaoxin” prescriptions, salidroside and betaine. For the quantitative analysis, the characteristic signals for H-3 and H-5 of salidroside at δ 7.08 ppm (2H, J = 8.58 Hz), as well as the equivalent methyl groups of betaine at δ 3.12 ppm, were selected. The verification of the analytical method was accurate and in conformity with the guidance of the Chinese Pharmacopoeia. Furthermore, it has been applied to the quality assurance of products from different pharmaceutical companies. The results show that the content of salidroside in different products was satisfactory consistent with the results determined by high-performance liquid chromatography. This work implied that 1H NMR represents a feasible alternative to liquid chromatography for quantitation of salidroside and was suitable for the more comprehensive quality control of “xinnaoxin” commercial products by the simultaneous quantification of salidroside and betaine.

This study investigated the effect of fermentation by Lactobacillus plantarum CGMCC 14177 strain on physicochemical properties and morphological characteristics of potato starch. The maximum total amylase and α-amylase production of L. plantarum CGMCC 14177 were 286.8 and 208.1 U/g, respectively. Fermented granules clearly exhibited pocked and dimpled surfaces. The granule properties changed to have a 1.9% increase in relative crystallinity. Overall the starch changed to have slight increases in onset and peak temperature, but resulted decreases of conclusion temperature and enthalpy. Fermentation decreased peak viscosity and breakdown value, while increased trough viscosity, final viscosity, and setback. Further analysis showed that fermentation increased the gel hardness and chewiness of the potato starch, but made little differences in the springiness, cohesiveness and resilience. Collectively, these results provide insight on how Lactobacillus strains can be used to modify the physicochemical properties of potato starch in ways that extend its use in industrial applications.

The oncogenic fusion protein AML1-ETO retains the ability of AML1 to interact with the enhancer core DNA sequences, but blocks AML1-dependent transcription. Previous studies have shown that post-translational modification of AML1-ETO may play a role in its regulation. Here we report that AML1-ETO-positive patients, with high histone lysine methyltransferase Enhancer of zeste homolog 1 (EZH1) expression, show a worse overall survival than those with lower EZH1 expression. EZH1 knockdown impairs survival and proliferation of AML1-ETO-expressing cells in vitro and in vivo. We find that EZH1 WD domain binds to the AML1-ETO NHR1 domain and methylates AML1-ETO at lysine 43 (Lys43). This requires the EZH1 SET domain, which augments AML1-ETO-dependent repression of tumor suppressor genes. Loss of Lys43 methylation by point mutation or domain deletion impairs AML1-ETO-repressive activity. These findings highlight the role of EZH1 in non-histone lysine methylation, indicating that cooperation between AML1-ETO and EZH1 and AML1-ETO site-specific lysine methylation promote AML1-ETO transcriptional repression in leukemia., The oncogenic fusion protein AML1-ETO has the ability of AML1 to interact with DNA but blocks AML1-dependent transcription. Here the authors report that histone lysine methyltransferase EZH1 interacts with AML1-ETO and methylates AML1-ETO at lysine 43, promoting AML1-ETO transcriptional repression in leukemia.

Full atomistic molecular dynamics simulations are performed on tetra-sulfides and undoped conjugated polymers pernigraniline base polyaniline (PNB), leucoemeraldine base polyaniline (LEB), poly (3,4-ethylenedioxythiophene) (PEDOT) and polypyrrole (PPY) to investigate the binding effectiveness between polysulfides and polymer binders. The weight ratio between sulfur and binder in lithium–sulfur cells is considered in 1:1 v/v mixture of dioxolane/dimethoxyethane. The simulations reveal that the end group 2 of PNB can effectively bind a lithium tetra-sulfide (i.e. Li2S4) cluster or 2 out of 43 Li2S4 molecules with the effect of solvent. However, repeat units of PNB, LEB, PEDOT and PPY seem ineffective in binding solvated Li2S4 through non-bonded interaction, especially when the concentration of tetra-sulfide/binder in a local domain of the cathode is low. Therefore, polymers with this specific functional group (i.e. the end group 2 of PNB) are suggested to be further studied as potential effective binders to inhibit the shuttle effect of solvated lithium polysulfides. Also, since the solvent has considerable impact on the binding effectiveness between tetra-sulfides and binder, it is suggested to take advantage of the explicit solvation models, such as those built in this work, to predict how other influencing factors affect binding between polysulfides and polymers.

Evolution of domestic wastes into competitive battery materials at less expense is a rational strategy of "killing two birds with one stone", and never better for grid-scale energy-storage utilizations wherein achieving great energy density is less crucial than environmental friendliness and cost. To checkout this concept, we herein select Fe2N, a conductive conversion-type anode for Li-/Na-ion batteries (LIBs/SIBs), as a paradigm study. Rusty/plastic wastes-evolved anodes with a proper tap density of 1.74 g cm−3 are composed of numerous nanoparticles where each Fe2N unit is evenly configured in robust carbon sheath. Such electrodes demonstrate impressive specific capacities under varied areal mass loading ratios of 3∼15 mg cm-2, outstanding rate capabilities and cyclic stability. To judge their promise in practical usage, we successively choose economical LiFePO4 and phase-stable Na3V2(PO4)3 as pairing cathodes to build full-cell LIBs/SIBs. This wastes-to-battery protocol may pave a way to advance practical techniques for sustainable usage beyond.

Poly (lactic-co-glycolic acid) (PLGA) copolymers have been broadly used in controlled drug release applications. Because these polymers are biodegradable, they provide an attractive option for drug delivery vehicles. There are a variety of material, processing, and physiological factors that impact the degradation rates of PLGA polymers and concurrent drug release kinetics. This work is intended to provide a comprehensive and collective review of the physicochemical and physiological factors that dictate the degradation behavior of PLGA polymers and drug release from contemporary PLGA-based drug-polymer products. In conjunction with the existing experimental results, analytical and numerical theories developed to predict drug release from PLGA-based polymers are summarized and correlated with the experimental observations. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1692-1716, 2017.

The oncoprotein RUNX1-ETO is the fusion product of t(8;21)(q22;q22) and constitutes one of the most common genetic alterations in acute myeloid leukemia (AML). Abnormal c-KIT overexpression is considered an independent negative prognostic factor for relapse and survival in t(8;21) AML patients. However, the molecular mechanism of high c-KIT expression in t(8;21) AML remains unknown. In this study, we detected RUNX1-ETO and c-KIT gene expression in AML-M2 patients and verified the overexpression of c-KIT in t(8;21) AML patients. We also found that c-KIT overexpression was a poor prognostic indicator in RUNX1-ETO positive AML patients, but not in RUNX1-ETO negative AML patients. We used the dual-luciferase and ChIP assays to demonstrate that the RUNX1-ETO protein epigenetically trans-activates c-KIT by binding to the c-KIT promoter and recruiting the histone acetyltransferase P300 to the c-KIT promoter, elucidating the mechanism of the abnormally increased c-KIT expression in t(8;21) AML patients. Moreover, pharmacological studies revealed that C646, a P300 inhibitor, could inhibit proliferation, induce apoptosis and arrest the cell cycle more effectively in RUNX1-ETO positive cells than in negative ones. The levels of c-KIT and RUNX1-ETO proteins were also decreased with C646 treatment in RUNX1-ETO positive cells. These findings suggested that P300 could be a therapeutic target and that C646 could be used as a potential treatment for RUNX1-ETO positive AML patients. Interestingly, using the dual-luciferase assay, we also found that the binding capacity of RUNX1-ETO9a, a truncated RUNX1-ETO isoform, to the c-KIT promoter was stronger than that of RUNX1-ETO, suggesting RUNX1-ETO9a as another valuable therapeutic target in t(8;21) AML.

In different parts of the gastrointestinal tract, the rate of drug release from polyelectrolyte hydrogel tablets is highly affected by variance of ionic concentration. This research aims at revealing clearly how the drug release from a hydrogel matrix is affected by ionic concentration of external solution through the finite element simulation and triphasic mechanism model. The coupled relationship of the motions including the polyelectrolyte hydrogel swelling, the water flow and the ion diffusion, is illustrated in the present work. In order to simulate the drug controlled release from a swollen polyelectrolyte hydrogel carrier, the mathematical model was built on the basis of the multiphasic theory of polyelectrolyte hydrogels. Finally, the reliability of the simulation method was verified qualitatively by experimental results. The results reveal that when the initial concentration of fixed anions of polymer network is higher than the concentration of free anions in the external solution, the drug release rate increases with increasing the ionic concentration of the external solution. The research is helpful for the optimal design of oral drug release in gastrointestinal tract.

We report the development of a new ultrasensitive approach for label-free DNA detection using [...]

The infrared normal spectral emissivity of the oxidized molybdenum was measured during thermal oxidation process, and the integral emissivity was calculated from the data of spectral emissivity. It is found that the surface oxidation has a remarkable effect on the spectral emissivity of molybdenum, and the spectral emissivity curves become more fluctuant with the increase in oxidation time. The integral emissivity grows exponentially with the oxidation time at 773 K, remains almost constant at 823 K, and fluctuates at 873 and 923 K. The X-ray fluorescence spectrometer, the X-ray diffraction, and the scanning electron microscopy were employed to analyze the changes in surface composition and surface morphology. The results show that the most probable reason for the variation of integral emissivity is the change in surface roughness caused by the variation in the size and shape of oxide particle on specimen surface.

The application of nanofiltration in industrial fields is increasing rapidly in recent years, especially in drinking water treatment. Nevertheless, the mechanism of mass transport through these membranes has not yet been fully understood. And the optimal design of nanofiltration processes still faces challenges. At first, the Donnan Steric Pore Model (DSPM) is described in this paper, which is constructed on the basis of the extended Nernst-Planck equation for the prediction of the nanofiltration process of polymeric membrane. Then the DSPM model is used to characterize three kinds of membranes (AFC40, CA30 and NTR7450) for the nanofiltration of 50 mol/m(3) NaCl solution and NTR7450 membrane for the nanofiltration of NaCl and MgSO4 solution with different concentrations. The simulated results and their comparison with experimental results show that the DSPM model can effectively predict the membrane performance. And then a description of the Pores and Polarization Transport Model (PPTM) is presented, which is developed on the basis of the DSPM model, in order for characterizing cross-flow nanofiltration. The PPTM model combines the convection-diffusion-migration transport in the nanopores with the transport through the concentration polarization layer. To improve the PPTM model in the aspect of using an empirical model to describe the velocity field of solution above the membrane, the velocity profile in solution is solved by Navier-Stokes equation and continuity equation in this paper. The cross-flow nanofiltration of polymeric membrane is simulated using the finite element method, by coupling mass transfer in the membrane with ion concentration and velocity profile in solution above the membrane. By the comparison with experimental results and traditional PPTM results, it can be found that the modified method can reflect the change tendencies of ion concentration and velocity profile in solution, and their values are more in line with the values of experiments. The improved model can provide more reliable theoretical basis for the optimal design of cross-flow nanofiltration processes of polymeric membrane.