Transition metal–nitrogen–carbon (TM–N–C) nanomaterials are promising platinum-based substitutes for the oxygen reduction reaction (ORR). However, large-scale commercial production of high-efficiency, durable TM–N–C catalysts remains a formidable challenge. In this work, a facile ″ZIF-on-ZIF″ strategy is first adopted to design ZIF-8@ZIF-67 core–shell polyhedral nanocages, and then, ferrocene (Fc) is added to form ZIF-8@ZIF-67@Fc double-layer encapsulating polyhedral nanocages. Finally, Zn, Co, and Fe tridoped N–C nanocages (ZnCoFe–N–C) as the high-efficiency ORR electrocatalyst are prepared through high-temperature annealing. Benefiting from the trimetal, nitrogen and carbon species bond to each other to form highly efficient active sites, and the material exhibits outstanding performance in 0.1 M KOH, onset potential and half-wave potential of up to 0.95 and 0.878 V (vs RHE), respectively, and long-term durability and methanol tolerance. Furthermore, when utilizing as a zinc–air battery (ZAB) air electrode, it exhibits wonderful indicators, reflected in an open circuit voltage of 1.525 V, power density of 350.2 mW cm–2, and specific capacity of 794.7 mAh gzn –1, which outperforms the benchmark Pt/C catalyst. This work provides a facile and effective strategy to obtain a highly efficient and stable TM–N–C electrocatalyst for the ORR in ZABs.

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Repetitive transcranial magnetic stimulation (rTMS) may have the potential to prevent depressive relapse. This assessor-blinded, randomized controlled study was designed to evaluate the efficacy and safety of rTMS as a mono- and combination therapy in the prevention of depressive relapse/recurrence. A total of 281 depressed patients who had achieved stable full or partial remission on a 6-month antidepressant (ADP) run-in treatment were randomly assigned to an rTMS (n = 91), ADP (n = 108), or combined (rTMS + ADP, n = 82) treatment group for 12 months. Monthly clustered rTMS was conducted in 5–10 sessions over a 3–5-day period. Maintenance outcomes were assessed using time to relapse/recurrence and relapse/recurrence rate. Overall, 71.2% (200/281) of the participants completed the treatment per the protocol. rTMS + ADP and rTMS significantly reduced the risk of relapse/recurrence compared with ADP (P = 0.000), with hazard ratios of 0.297 and 0.466, respectively. Both rTMS-containing regimens produced significantly lower relapse/recurrence rates than ADP (15.9% and 24.2% vs. 44.4%, P < 0.001). In the relapsed/recurrent subgroup, first-episode depressed, rTMS-treated patients had a markedly lower relapse/recurrence rate than ADP-treated patients. Five patients on the ADP-containing regimens, but none on rTMS alone, developed acute mania. The rTMS-containing regimens had considerably more certain side effects than did the ADP group. We concluded that TMS, whether as a mono- or additional therapy, is superior to antidepressants in preventing depressive relapse/recurrence, particularly in first-episode depressed patients. The treatment does not increase the risk of manic switch, but may increase the risk of certain side effects.

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A new application of the genuinely entangled six-qubit state introduced recently by Tapiador et al. (J. Phys. A 42:415301, 2009) is investigated for the quantum teleportation of an arbitrary three-qubit state and for quantum information splitting (QIS) of an arbitrary two-qubit state. For QIS, we have shown that it can be completed perfectly with two distinct measurement methods. In our scheme, the joint Bell-state measurement and the joint multi-qubit measurement are needed. This quantum teleportation and QIS schemes are deterministic.

A new scheme for controlled teleportation of an arbitrary two-particle pure or mixed state with the help of a five-qubit cluster state is proposed in detail. In this scheme, a five-particle cluster state is shared by a sender, a controller and a receiver. At first, the sender performs a four-qubit von-Neumann measurement on the qubits at hand, and the controller performs a Hadamard measurement on his qubit. Then the receiver can reconstruct the arbitrary two-particle pure or mixed state by performing some appropriate unitary transformations on his particles after he knows the measure results of the sender and the controller. This controlled teleportation scheme is deterministic.