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Trimetal Fe0.8CoMnO4 (FCMO) nanocrystals with a diameter of about 50 nm perfectly embedded in N doped‐carbon composite nanofibers (denoted as FCMO@C) are successfully prepared through integrating double‐nozzle electrospinning with a drying and calcination process. The as‐prepared FCMO@C nanofibers maintain a high reversible capacity of 420 mAh g−1 and about 90% capacity retention after 200 cycles at 0.1 A g−1. For a long‐term cycle, the FCMO@C electrode exhibits excellent cycling stability (87% high capacity retention at 1 A g−1 after 950 cycles). Kinetic analysis demonstrates that the electrochemical characteristics of the FCMO@C corresponds to the pseudocapacitive approach in charge storage as an anode for sodium ion batteries, which dominantly attributes the credit to FCMO nanocrystals to shorten the migration distance of Na+ ions and the nitrogen‐doped carbon skeleton to enhance the electronic transmission and favorably depress the volume expansion during the repeated insertion/extraction of Na+ ions. More significantly, a self‐supported mechanism via continuous electrochemical redox reaction of Fe, Co, and Mn can effectively relieve the volume change during charge and discharge. Therefore, this work can provide a new avenue to improve the sodium storage performance of the oxide anode materials. [ABSTRACT FROM AUTHOR]

The brain mechanisms by which animals deal with multiple experiences to predict outcomes are not yet fully understood. We explored the choice strategies that flies use to assess degrees of disadvantage, as well as how flies weigh past and recent experiences to guide decisions. Drosophila were exposed to two conditioning events in a T-maze: an odor paired with an electric shock followed by a second odor paired with an electric shock of a different intensity. Subsequently, flies were forced to choose between the two odors. We found that flies chose to avoid the more ‘dangerous’ odor by a linear subtraction mechanism that was based on two coexisting memories. We also found that flies weighed experiences of the same danger level (60 V electric shocks) according to the times when the experiences had occurred. More recent experiences had a greater impact and past experiences gradually became ‘overlooked’ during decisions as the time delay between the two events lengthened. However, the past memory was not so much disrupted as it was overshadowed by recent memories during decisions. Finally, when a past experience was more disadvantageous, wild-type flies were able to coordinate both the temporal factor and the degree of disadvantage into their decisions. By contrast, amnesiac mutant flies made choices completely according to the temporal factor, ignoring the degree of disadvantage. Taken together, wild-type flies are able to store multiple olfactory memories and can coherently evaluate learned experiences to guide their decisions according to the degree of disadvantage and/or the temporal factor. [ABSTRACT FROM AUTHOR]