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58 V and better stability, which shows the satisfying electrocatalyst for the OWS compared to control materials. This method ensures the tight and uniform growth of the fast nucleating and stable materials on substrate and can be further applied for practical electrochemical reactions. © 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.Single-atom catalysts (SACs) are efficient for maximizing electrocatalytic activity, but have unsatisfactory activity for the oxygen evolution reaction (OER). Herein, the NaCl template synthesis of individual nickel (Ni) SACs is reported, bonded to oxygen sites on graphene-like carbon (denoted as Ni-O-G SACs) with superior activity and stability for OER. A variety of characterizations unveil that the Ni-O-G SACs present 3D porous framework constructed by ultrathin graphene sheets, single Ni atoms, coordinating nickel atoms to oxygen. Consequently, the catalysts are active and robust for OER with extremely low overpotential of 224 mV at current density of 10 mA cm-2, 42 mV dec-1 Tafel slope, oxygen production turn over frequency of 1.44 S-1 at 300 mV, and long-term durability without significant degradation for 50 h at exceptionally high current of 115 mA cm-1, outperforming the state-of-the-art OER SACs. A theoretical simulation further reveals that the bonding between single nickel and oxygen sites results in the extraordinary boosting of OER performance of Ni-O-G SACs. Therefore, this work opens numerous opportunities for creating unconventional SACs via metal-oxygen bonding. © 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.Solid composite electrolytes (SCEs) that combine the advantages of solid polymer electrolytes (SPEs) and inorganic ceramic electrolytes (ICEs) present acceptable ionic conductivity, high mechanical strength, and favorable interfacial contact with electrodes, which greatly improve the electrochemical performance of all-solid-state batteries compared to single SPEs and ICEs. However, there are many challenges to overcome before the practical application of SCEs, including the low ionic conductivity less than 10-3 S cm-1 at ambient temperature, poor interfacial stability, and high interfacial resistance, which greatly restrict the room temperature performance. Herein, the advances of SCEs applied in all-solid-state lithium batteries are presented, including the Li ion migration mechanism of SCEs, the strategies to enhance the ionic conductivity of SCEs by various morphologies of ICEs, and construction methods of the low resistance and stable interfaces of SCEs with both cathode and anode. Finally, some typical applications of SCEs in lithium batteries are summarized and future development directions are prospected. This work presents how it is quite significant to further enhance the ionic conductivity of SCEs by developing the novel SPEs with the special morphology of ICEs for advanced all-solid-state lithium batteries. © 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.Cancer stem cells (CSCs) are the main cause of tumor development, metastasis, and relapse. CSCs are thus considered promising targets for cancer therapy. However, it is hard to eradicate CSCs due to their inherent plasticity and heterogeneity, and the underlying mechanism of the switch between non-CSCs and CSCs remains unclear. Here, it is shown that miR-135a combined with SMYD4 activates Nanog expression and induces the switch of non-CSCs into CSCs. The miR-135a level, once elevated, lowers the methylation level of the CG5 site in the Nanog promoter by directly targeting DNMT1. SMYD4 binds to the unmethylated Nanog promoter to activate Nanog expression in Nanog-negative tumor cells. The in vivo regulation of miR-135a levels could significantly affect both the CSCs proportion and tumor progression. These findings indicate that DNA methylation of the Nanog promoter modulates the switch of non-CSCs into CSCs under the control of the miRNA-135 level. In addition, the related pathways, miR-135a/DNMT1 and SMYD4, involved in these processes are potential targets for CSC-targeted therapy. © 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.As the power conversion efficiency (PCE) of perovskite solar cells (PSCs) is increased to as high over 25%, it becomes pre-eminent to study a scalable process with wide processing window to fabricate large-area uniform perovskite films with good light-trapping performance. A stable and uniform intermediate-state complex film is obtained by using tetramethylene sulfoxide (TMSO), which extends the annealing window to as long as 20 min, promotes the formation of a high-quality perovskite film with larger grains (over 400 nm) and spontaneously forms the surface texture to result in an improved fill factor and open-circuit voltage (V oc). Moreover, the superior surface texture significantly increases the long-wavelength response, leading to an improved short-circuit current density (J sc). As a result, the maximum PCE of 21.14% is achieved based on a simple planar cell structure without any interface passivation. Moreover, a large area module with active area of 6.75 cm2 is assembled using the optimized TMSO process, showing efficiency as high as 16.57%. CB-5339 research buy The study paves the way to the rational design of highly efficient PSCs for potential scaled-up production. © 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.Millions worldwide suffer from arthritis of the hips, and total hip replacement is a clinically successful treatment for end-stage arthritis patients. Typical hip implants incorporate a cobalt alloy (Co-Cr-Mo) femoral head fixed on a titanium alloy (Ti-6Al-4V) femoral stem via a Morse taper junction. However, fretting and corrosion at this junction can cause release of wear particles and metal ions from the metallic implant, leading to local and systemic toxicity in patients. This study is a multiscale structural-chemical investigation, ranging from the micrometer down to the atomic scale, of the underlying mechanisms leading to metal ion release from such taper junctions. Correlative transmission electron microscopy and atom probe tomography reveals microstructural and compositional alterations in the subsurface of the titanium alloy subjected to in vitro gross-slip fretting against the cobalt alloy. Even though the cobalt alloy is comparatively more wear-resistant, changes in the titanium alloy promote tribocorrosion and subsequent degradation of the cobalt alloy.