Hardware implementation of artificial synaptic devices that emulate the functions of biological synapses is inspired by the biological neuromorphic system and has drawn considerable interest. Here, a three‐terminal ferrite synaptic device based on a topotactic phase transition between crystalline phases is presented. The electrolyte‐gating‐controlled topotactic phase transformation between brownmillerite SrFeO2.5 and perovskite SrFeO3−δ is confirmed from the examination of the crystal and electronic structure. A synaptic transistor with electrolyte‐gated ferrite films by harnessing gate‐controllable multilevel conduction states, which originate from many distinct oxygen‐deficient perovskite structures of SrFeOx induced by topotactic phase transformation, is successfully constructed. This three‐terminal artificial synapse can mimic important synaptic functions, such as synaptic plasticity and spike‐timing‐dependent plasticity. Simulations of a neural network consisting of ferrite synaptic transistors indicate that the system offers high classification accuracy. These results provide insight into the potential application of advanced topotactic phase transformation materials for designing artificial synapses with high performance.

This paper mainly focuses on the application of nanostructured MoO 3 materials in both energy and environmental catalysis fields. MoO 3 has wide tunability in bandgap, a unique semiconducting structure, and multiple valence states. Due to the natural advantage, it can be used as a high-activity metal oxide catalyst, can serve as an excellent support material, and provide opportunities to replace noble metal catalysts, thus having broad application prospects in catalysis. Herein, we comprehensively summarize the crystal structure and properties of nanostructured MoO 3 and highlight the recent significant research advancements in energy and environmental catalysis. Several current challenges and perspective research directions based on nanostructured MoO 3 are also discussed.Molecules 2020, 25, 18 2 of 26 applications in energy and environmental catalysis on account of their relatively low cost, high activity, and stability [9][10][11][12].Molybdenum oxide (MoO 3 ), a kind of transition metal oxide with a n-type semiconducting, nontoxic nature and high stability, has attracted a lot of attention. In particular, nanostructured MoO 3 has demonstrated superior properties to bulk MoO 3 , which is successfully employed in rechargeable batteries [13], capacitors [14], photocatalysis [15], electrocatalysis [16], gas sensors [17], and other applications [6]. The extended tunnels between the MoO 6 octahedra in MoO 3 are suitable for insert/de-insert mobile ions, such as H + and Li + , and multiple oxidation states can enable rich redox reactions. Moreover, the superiorities of low cost, chemical stability, high theoretical specific capacity (1117 mA·h/g), and the environmentally friendly nature make nanostructured MoO 3 exceptional electrode materials for rechargeable batteries capacitors [13,18]. MoO 3 has been investigated as the photocatalyst in terms of its anisotropic layered structure for absorbing UV, as well as visible light. Introducing a defect band by H + intercalation or oxygen vacancies can create defect state and decrease MoO 3 bandgap, which effectively increase the photocatalytic activity [15]. Each oxygen atom bonds to only one molybdenum atom of MoO 6 octahedra, and oxygen vacancy generates Mo dangling bond. MoO 3 favors the adsorption of water molecules in oxygen vacancies, which act as electron acceptors and consequently reduce the energy barrier make it highly reactive for electrocatalysis [2,19]. As a good gasochromic material, MoO 3 has efficient positive-ion accommodation and good charge transfer, and it can be used as an optical-based gas sensor. Moreover, relying on the change in the conductance of the oxide-on-gas adsorption/reaction, MoO 3 has been used for NO, NO 2 , CO, H 2 , NH 3 , and other gases [17]. The unique structure strongly affects the performances. Large efforts have been made to obtain nanostructured MoO 3 with appealing properties by engineering multiple synthetic strategies for the applications in various fields. A variety of methods have been developed, including hydrothermal met...

Background Clinical studies assessing the feasibility and accuracy of three stone scoring systems’s (SSSs: Guy’s stone score, CROES nomogram and S.T.O.N.E nephrolithometry scoring system) have reported contradictory outcomes. This systematic evaluation was performed to obtain comprehensive evidence with regard to the feasibility and accuracy of three SSSs. Methods A systematic search of Embase, Pubmed, Medline, and the Cochrane Library was conducted to identify studies that compared three SSSs up to Mar 2018. Patients were categorized according to stone free (SF) and no-stone free (NSF), Outcomes of interest included perioperative variables, stone-free rate (SFR), and complications. Results Ten studies estimating three SSSs were included for meta-analysis. The results showed that SF patients had a significantly lower proportion of male (OR = 1.48, P = 0.0007), lower stone burden (WMD = -504.28, P < 0.0001), fewer No of involved calyces (OR = -1.23, P = 0.0007) and lower proportion of staghorn stone (OR = 0.33, P < 0.0001). Moreover, SF patients had significantly lower score of Guy score (WMD = -0.64, P < 0.0001), but, S.T.O.N.E. score (WMD = -1.23, P < 0.0001) and a higher score of CROES nomogram (WMD = 29.48, P = 0.003). However, the comparison of area under curves (AUC) of predicting SFR indicated that there was no remarkable difference between three SSSs. Nonetheless, Guy score was the only stone scoring system that predicted complications after PCNL (WMD = -0.29, 95% CI: − 0.57 to − 0.02, P = 0.03). Conclusions Our meta-analysis indicated that the three SSSs were equally, feasible and accurate for predicting SFR after PCNL. However, Guy score was the only stone scoring system that predicted complications after PCNL.

A novel two-site chemodosimeter (SWJT-4) based on fluorescein skeleton to detect diethyl chlorophosphate (DCP) was designed and synthesized. It is a turn-on fluorescent probe for DCP with good selectivity and obvious color change in aqueous solution. Interestingly, the two oxime groups of SWJT-4 as dual response sites initiated different reactions with DCP to form a cyano group and an isoxazole ring, respectively. The corresponding mechanism was confirmed by 1H NMR, MS and DFT calculation. Moreover, SWJT-4 could be used as a fluorescent test paper to detect DCP vapor.

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Abstract. The response to prescribed burning of plant communities ranging from dry to wet habitats was monitored using permanent plots sampled from 1989 to 1993. Temporal controls for fire effects were provided by matched sets of plots protected from fire by newly constructed fire breaks. Changes in species composition were studied by ordination of strata of trees (> 5 cm DBH), small trees (2–5 cm DBH), large saplings (1–2 cm DBH), and small saplings and seedlings (50–140 cm tall). Results show that changes occurred largely in the small tree stratum, in which xeric species increased in importance. Although there were changes in sapling and seedling strata, no clear direction of change was recognized. Fire had little effect on the tree stratum. Of the seven community types under study, three types, sandhill, upland pine, and upperslope pine‐oak, were most strongly affected, as indicated by post‐fire change in positions of samples representing these communities in ordination space and reduction in understory species abundance. Samples representing the other four mesic and wet communities showed little or no change in their positions. These short‐term results indicate that changes in vegetation resulting from fire were small and were mostly restricted to the dry types in which possible compositional change is expected to occur. This differential effect of fire suggests that the influence of fire is secondary to that of topographical and soil gradients in determining vegetation pattern under current fire regimes. Fire seems to reinforce an overall vegetation gradient controlled by soil in southeastern Texas.

A novel near-infrared (NIR) fluorescent probe (SWJT-9) was designed and synthesized for the detection of hypochlorite anion (ClO−) using a diaminomaleonitrile group as the recognition site. SWJT-9 had large Stokes shift (237 nm) and showed an excellent NIR fluorescence response to ClO− with the color change under the visible light. It showed a low detection limit (24.7 nM), high selectivity, and rapid detection (within 2 min) for ClO−. The new detection mechanism of SWJT-9 on ClO− was confirmed by 1H NMR, MS spectrum, and the density functional theory (DFT) calculations. In addition, the probe was successfully used to detect ClO− in HeLa cells.