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Background and Purpose: Source-based morphometry(SBM) has been used in multicenter studies pooling magnetic resonance imaging data across different scanners to advance the reproducibility of neuroscience research. In the present study, we developed an analysis strategy for Scanner-Specific Detection (SS-Detect) of SBPs in multiscanner studies, and evaluated its performance relative to a conventional strategy.Methods: In the first experiment, the SimTB toolbox was used to generate simulated datasets mimicking 20 different scanners with common and scanner-specific SBPs. In the second experiment, we generated one simulated SBP from empirical gray matter volume (GMV) datasets from two different scanners. Moreover, we applied two strategies to compare SBPs between schizophrenia patients' and healthy controls' GMV from two scanners.Results: The outputs of the conventional strategy were limited to whole-sample-level results across all scanners; the outputs of SS-Detect included whole-sample-level and scanner-specific results. In the first simulation experiment, SS-Detect successfully estimated all simulated SBPs, including the common and scanner-specific SBPs, whereas the conventional strategy detected only some of the whole-sample SBPs. The second simulation experiment showed that both strategies could detect the simulated SBP. Quantitative evaluations of both experiments demonstrated greater accuracy of the SS-Detect in estimating spatial SBPs and subject-specific loading parameters. In the third experiment, SS-Detect detected more significant between-group SBPs, and these SBPs corresponded with the results from voxel-based morphometry analysis, suggesting that SS-Detect has higher sensitivity in detecting between-group differences.Conclusions: SS-Detect outperformed the conventional strategy and can be considered advantageous when SBM is applied to a multiscanner study. [ABSTRACT FROM AUTHOR]

Atomically dispersed catalysts have attracted attention in energy conversion applications because their efficiency and chemoselectivity for special catalysis are superior to those of traditional catalysts. However, they have limitations owing to the extremely low metal-loading content on supports, difficulty in the precise control of the metal location and amount as well as low stability at high temperatures. We prepared a highly doped single metal atom hybrid via a single-step thermal pyrolysis of glucose, dicyandiamide, and inorganic metal salts. High-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption fine structure spectroscopy (XAFS) revealed that nitrogen atoms doped into the graphene matrix were pivotal for metal atom stabilization by generating a metal-Nx coordination structure. Due to the strong anchoring effect of the graphene matrix, the metal loading content was over 4 wt.% in the isolated atomic hybrid (the Pt content was as high as 9.26 wt.% in the Pt-doped hybrid). Furthermore, the single iron-doped hybrid (Fe@N-doped graphene) showed a remarkable electrocatalytic performance for the oxygen reduction reaction. The peak power density was ∼199 mW·cm−2 at a current density of 310 mA·cm−2 and superior to that of a commercial Pt/C catalyst when it was used as a cathode catalyst in assembled zinc-air batteries. This work offered a feasible approach to design and fabricate highly doped single metal atoms (SMAs) catalysts for potential energy applications. [ABSTRACT FROM AUTHOR]

Rationally designing cheap and efficient electrocatalysts at the atomic level is highly desirable for the hydrogen evolution reaction (HER). Here, we demonstrate a metallic MoS 2 electrocatalyst decorated with platinum single atoms. When combined with electron microscopy observations, our synchrotron X-ray characterizations and theoretical calculations clearly reveal that the doped Pt atoms bond to S atoms on the surface of MoS 2 . Notably, these Pt single atoms serve as critical active centers for the HER through capturing H + from the solution. The optimized Pt-MoS 2 catalysts achieve significantly enhanced HER performance due to the single-atom coordination effect. This finding is expected to facilitate further realization of hybridized catalysts through the monatomic riveting strategy.