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To engineer tissue restoration, it is necessary to provide a bioactive, mechanically robust scaffold. Electrospun poly(ε‐caprolactone) (PCL) nanofiber is a promising biomaterial candidate with excellent mechanical properties, but PCL scaffolds are inert and lack natural cell recognition sites. To overcome this problem we investigated the incorporation of Antheraea pernyi silk fibroin (ASF) containing inherent RGD tripeptides with PCL in electrospinning process. The mixing ratios showed remarkable impact on the properties of hybrid nanofibers. Increasing PCL content significantly enhanced the mechanical properties of nanofibers. In particular, the mechanical properties were remarkably enhanced when PCL content increased from 50 wt% to 70 wt%. Moreover, the biological assays based on endothelial cells showed promoted cell viability when ASF content reached to 30 wt%. The data demonstrated that the nanofiber containing 70% of PCL and 30% of ASF achieved the most balanced performances for integrating the mechanical properties of PCL and the bioactivity of ASF. Furthermore, biomimetic alignment of 70PCL/30ASF nanofibers was achieved, which could support PC12 neuron‐like cell growth and guide neurite outgrowth, providing a potentially useful option for the engineering of oriented tissues. The results show that the PCL/ASF hybrid nanofibers can be considered as a promising candidate for tissue engineering scaffolds. POLYM. ENG. SCI., 57:206–213, 2017. © 2016 Society of Plastics Engineers

We experimentally demonstrate a dynamical classification approach for investigation of topological quantum phases using a solid-state spin system through nitrogen-vacancy (NV) center in diamond. Similar to the bulkboundary correspondence in real space at equilibrium, we observe a dynamical bulk-surface correspondence in the momentum space from a dynamical quench process. An emergent dynamical topological invariant is precisely measured in experiment by imaging the dynamical spin-textures on the recently defined band-inversion surfaces, with high topological numbers being implemented. Importantly, the dynamical classification approach is shown to be independent of quench ways and robust to the decoherence effects, offering a novel and practical strategy for dynamical topology characterization, especially for high dimensional gapped topological phases.The topology of quantum systems has been developed into a major focus of research in physics since the discovery of quantum Hall effect [1,2]. Beyond the states of quantum matter characterized by Landau symmetry-breaking theory, the topological quantum phases bear a myriad of properties depending only on the topology [3-5], with the most celebrated paradigms discovered recently including the topological insulators [6][7][8][9][10][11] and semimetals [12,13]. Among the many exotic features emerging in a topological matter, the bulk-boundary correspondence is the most fundamental phenomenon showing that on the boundary gapless states can be obtained corresponding to and protected by the nontrivial topology in the bulk [14,15].At equilibrium, the number of topologically protected surface (edge) states is uniquely related to the bulk topological invariants [14,15]. This allows to detect topological insulators [8][9][10][11] and semimetals [12,13] by resolving the surface states from transport measurement or angle resolved photoemission spectroscopy. Apart from the direct measurement in condensed matter physics, quantum simulation may provide new strategies for the characterization [16][17][18][19][20][21][22][23][24][25][26][27][28][29]. For example, the band topology of 1D Su-Schrieffer-Heeger (SSH) chain can be determined by measuring the Zak phase [19,20], the bulk topology of a 2D Chern insulator can be observed by Hall transport studies [21,22], by Berry curvature mapping [27], or by a minimal measurement strategy [28] of imaging the spin texture at symmetric Bloch space [29]. In addition, these systems naturally offer powerful probes and controllability in comparison with their condensed matter counterpart, which enables the study of non-equilibrium physics across topological phase transitions. A generic protocol in state-of-the-art experiments is to prepare a topologically trivial initial state and then observe the non-equilibrium dynamics after the Hamiltonian has been quenched into a topological regime. For such non-equilibrium process, the bulk-boundary correspondence, however, is no-longer valid [30][31][32][33]. A natural challenge is to find a generic method ...

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Although Fe3O4 has high capacity, the low conductivity and poor cycle stability have limited its application in supercapacitor. To address this issue, the core-shell structured Fe3O4@polypyrrole (Fe3O4@PPy) composite materials could...

Two Wells–Dawson arsenotungstate coordination polymers, [{CuII(bim)2}3(As2W18O62)] (1) and [(CuI 10pz10Cl4)­(As2W18O62)] (bim = 2,2′-biimidazole; pz = pyrazine), have been assembled via a hydrothermal method and fully characterized. Compound 1 exhibits a 2,6-connected two-dimensional hybrid layer based on asymmetrically modified {As2W18} anions and {Cu­(bim)2} linkers, which is extended to a three-dimensional network with a special interlayer structure and a one-dimensional tunnel. Compound 2 is a host–guest framework that consists of a Cu-pz-Cl network with 20-member square rings, 16-member irregular rings, and embedded eight-node {As2W18} guest molecules. Compounds 1 and 2 show uncommon specific capacitance (834.8 and 960.1 F g–1, respectively, at a current density of 2.4 A g–1), enduring cycling stability (capacitance retention rates of 89.3% and 91.9%, respectively, after 5000 cycles), and good electrical conductivity, which are superior to those of the unmodified zero-dimensional Dawson arsenotungstate compound and most reported electrode materials in terms of their stable structure, special layer spacing, and orderly channels. Moreover, the title compounds exhibit excellent electrocatalytic activity for oxidizing ascorbic acid and reducing nitrite.

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Benign prostatic hyperplasia (BPH) is a chronic condition which mainly affects elderly males. Existing scientific evidences have not completely revealed the pathogenesis of BPH. Glucose-regulated protein 78 (GRP78) is a member of the heat shock protein 70 superfamily, which serves as an important regulator in many diseases. This study aims at elucidating the role of GRP78 in the BPH process. Human prostate tissues, cultured human prostate cell lines (BPH-1 and WPMY-1) and clinical data from BPH patients were utilized. The expression and localization of GRP78 were determined with quantitative real time PCR (qRT-PCR), Western blotting and immunofluorescence staining. GRP78 knockdown and overexpression cell models were created with GRP78 siRNA and GRP78 plasmid transfection. With these models, cell viability, apoptosis rate, as well as marker levels for epithelial-mesenchymal transition (EMT) and oxidative stress (OS) were detected by CCK8 assay, flow cytometry analysis and Western blotting respectively. AKT/mTOR and MAPK/ERK pathways were also evaluated. Results showed GRP78 was localized in the epithelium and stroma of the prostate, with higher expression in BPH tissues. There was no significant difference in GRP78 expression between BPH-1 and WPMY-1 cell lines. In addition, GRP78 knockdown (KD) slowed cell growth and induced apoptosis, without effects on the cell cycle stage of both cell lines. Lack of GRP78 affected expression levels of markers for EMT and OS. Consistently, overexpression of GRP78 completely reversed all effects of knocking down GRP78. We further found that GRP78 modulated cell growth and OS via AKT/mTOR signaling, rather than the MAPK/ERK pathway. Overall, our novel data demonstrates that GRP78 plays a significant role in the development of BPH and suggests that GRP78 might be rediscovered as a new target for treatment of BPH.