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Highly flexible and foldable supercapacitor devices assembled using biotemplated polyaniline composite electrodes are described for the first time in this paper. This electrode architecture provides a facile fabrication route for creating abundant multiscale structures by using a rose flower design based on natural resources and facilitates designing a hierarchical ordering morphology that improves the redox exchange and ionic diffusion resistance between the electrodes and electrolyte. The polyaniline composite was prepared using a replica technique and synthesized through in situ oxidative polymerization by using aniline with reduced graphene oxide. The biotemplated electrodes show a high electrochemical specific capacitance of 626 F g−1 at a current density of 1 A g−1 in a three-electrode system, an excellent mechanical strength for enduring Z-type folding, and high cycling stability with a capacity retention of 87% (545 F g−1). Furthermore, in cyclic voltammetry analysis, the prototype devices exhibit extraordinary elasticity without side reactions in various bending angles. Regarding electrochemical performance, the device responds with a high energy density of 5.06 W h kg−1 and a high power density of 1685 W kg−1 when based on composite thin film electrodes and maintains 85% cycling retention as well as electrode performance after 1000 cycles. This study clearly reveals that fabricating hierarchical polyaniline composite electrodes through biotemplating yields high electrochemical performance and flexibility, making the electrodes useful in energy storage devices for portable electronic products.

The electrochemical stability of polyaniline (PANI) films is a key issue for their application as electrode materials. This work demonstrates that a low fraction (

Cellular cardiomyoplasty has been limited by poor graft retention after cell transplantation. To ensure good retention of the engrafted cells, a microfluidic device was used to fabricate spherical porous beads of poly(D,L-lactic-co-glycolic acid) as a platform for cell delivery. The beads thus obtained had a relatively uniform size, a highly porous structure, and a favorably interconnected interior architecture, to facilitate the transportation of oxygen and nutrients. These porous beads were loaded with human amniotic fluid stem cells (hAFSCs) to generate cellularized microscaffolds. Live/dead assay demonstrated that most of the cells in the porous constructs were viable. The hAFSCs that were grown in beads formed a complex three-dimensional organization with well-preserved extracellular matrices (ECM) according to their porous structure. Retention of the administered beads was clearly identified at the site of engraftment following an experimentally induced myocardial infarction in a rat model. The results of echocardiography, magnetic resonance imaging, and histological analyses suggest that the transplantation of hAFSC beads into an infarcted heart could effectively maintain its gross morphology, prevent successive ventricular expansion, and thereby improve the post-infarcted cardiac function. Immunofluorescent staining revealed that the microenvironment that was provided by the infarcted myocardium might offer cues for the induction of the engrafted hAFSCs into angiogenic and cardiomyogenic lineages. Our results demonstrate that the cellularized beads with endogenously secreted ECM were of sufficient physical size to be entrapped in the interstitial tissues following transplantation, thereby benefiting the infarcted heart.

Cell transplantation is a promising strategy for therapeutic treatment of ischemic heart diseases. In this study, cord blood mesenchymal stem cells (cbMSCs) and human umbilical vein endothelial cells (HUVECs) in the form of core-shell bodies (cbMSC/HUVEC bodies) were prepared to promote vascularization and restore heart functions in an experimentally-created myocardial infarction (MI) rat model. Saline, cbMSC bodies and HUVEC bodies were used as controls. In vitro results indicated that cbMSC/HUVEC bodies possessed the capability of heterotypic assembly of cbMSCs and HUVECs into robust and durable tubular networks on Matrigel. The up-regulated gene expressions of VEGF and IGF-1 reflected the robust expansion of tubular networks; in addition, the augmented levels of SMA and SM22 suggested smooth muscle differentiation of cbMSCs, possibly helping to improve the durability of networks. Moreover, according to the in vivo echocardiographic, magnetic resonance and computed-tomographic results, transplantation of cbMSC/HUVEC bodies benefited post-MI dysfunction. Furthermore, the vascularization analyses demonstrated the robust vasculogenic potential of cbMSC/HUVEC bodies in vivo, thus contributing to the greater viable myocardium and the less scar region, and ultimately restoring the cardiac function. The concept of core-shell bodies composed of perivascular cells and endothelial cells may serve as an attractive cell delivery vehicle for vasculogenesis, thus improving the cardiac function significantly.

Immigration is common in this increasingly globalized world. Immigration is a psycho-social-geographical transition that involves a series of losses and changes, most of them obvious and expected, but some of them hidden and unexpected. Immigration also involves changes in one’s identity, as inner change tries to match outer change. The original story of immigration—by Abraham in the Bible—highlights some of the issues immigrants typically confront. A survey of Taiwanese immigrants in San Francisco and Vancouver, Canada illustrates some of the most troubling of these issues. Congregations, particularly bicultural congregations, are especially well-equipped to minister to the needs of the newly immigrated. Pastors need to be sensitive to the issues and needs of immigrants in a world where we are all foreigners in one sense or another.

Myocardial infarction is often associated with abnormalities in electrical function due to a massive loss of functioning cardiomyocytes. This work develops a mesh, consisting of aligned composite nanofibers of polyaniline (PANI) and poly(lactic-co-glycolic acid) (PLGA), as an electrically active scaffold for coordinating the beatings of the cultured cardiomyocytes synchronously. Following doping by HCl, the electrospun fibers could be transformed into a conductive form carrying positive charges, which could then attract negatively charged adhesive proteins (i.e. fibronectin and laminin) and enhance cell adhesion. During incubation, the adhered cardiomyocytes became associated with each other and formed isolated cell clusters; the cells within each cluster elongated and aligned their morphology along the major axis of the fibrous mesh. After culture, expression of the gap-junction protein connexin 43 was clearly observed intercellularly in isolated clusters. All of the cardiomyocytes within each cluster beat synchronously, implying that the coupling between the cells was fully developed. Additionally, the beating rates among these isolated cell clusters could be synchronized via an electrical stimulation designed to imitate that generated in a native heart. Importantly, improving the impaired heart function depends on electrical coupling between the engrafted cells and the host myocardium to ensure their synchronized beating.

Polyaniline (PANI)/multi-walled carbon nanotube (MWNT) nanocomposite films with three-dimensional architectures on the surface were prepared using fresh plant leaves as a template through the nanocasting technique. The biomimetic surface morphology of the PANI nanocomposite electrodes, including multiscale papilla-like and nanoscale texture, were successfully replicated from Xanthosoma sagittifolium leaves. The morphology, roughness and dispersed MWNTs of the PANI/MWNT nanocomposites were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and atomic force microscopy. It was found that the well-dispersed MWNTs and the multiscale morphology formed a uniform nanocomposite, with an observed larger surface area, high specific capacitance and good cycling stability during the charge–discharge process. A specific capacitance as high as 535 F g−1 at a current density of 1 A g−1 was achieved for a 5 wt% MWNT loading coupled with the high roughness of the PANI nanocomposite, and the capacitance was maintained with the increment of the current density to 3 A g−1. These easily fabricated PANI nanocomposite electrodes show great potential for energy storage applications.