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Multivariate pattern analysis (MVPA) has played an extensive role in interpreting brain activity, which has been applied in studies with modalities such as functional Magnetic Resonance Imaging (fMRI), Magnetoencephalography (MEG) and Electroencephalography (EEG). The advent of wearable MEG systems based on optically pumped magnetometers (OPMs), i.e., OP-MEG, has broadened the application of bio-magnetism in the realm of neuroscience. Nonetheless, it also raises challenges in temporal decoding analysis due to the unique attributes of OP-MEG itself. The efficacy of decoding performance utilizing multimodal fusion, such as MEG-EEG, also remains to be elucidated. In this regard, we investigated the impact of several factors, such as processing methods, models and modalities, on the decoding outcomes of OP-MEG. Our findings indicate that the number of averaged trials, dimensionality reduction (DR) methods, and the number of cross-validation folds significantly affect the decoding performance of OP-MEG data. Additionally, decoding results vary across modalities and fusion strategy. In contrast, decoder type, resampling frequency, and sliding window length exert marginal effects. Furthermore, we introduced mutual information (MI) to investigate how information loss due to OP-MEG data processing affect decoding accuracy. Our study offers insights for linear decoding research using OP-MEG and expand its application in the fields of cognitive neuroscience. [ABSTRACT FROM AUTHOR]

Pd membranes act in an important role in H2 purification and H2 production in membrane reactors. Pd-Ag alloy membranes fabricated by consecutive electroless- and electroplating process on alumina tubes exhibited good stability under stringent heating/cooling cycles at a ramp rate of 10 K/min, imitating practical fast initiation or emergency shutdown conditions. Bilayer Pd-Ag membranes can form dense and uniform alloy after thermal treatment for 24 h at 823 K under H2 atmosphere, despite a porous structure due to the development of liquid-like properties above Tamman temperature to enforce the migrativity. On the contrary, alloying under N2 atmosphere resulted in a Pd-enriched layer. This led to a lower H2 flux but superior thermal stability compared to that alloying under H2 atmosphere. The trilayer approach of electroless-plated Pd, electro-polated Ag and electroless-plated Pd is not suitable to achieve homogeneous Pd-Ag alloys, which, on the other hand, presented the occurrence of a small gap between top Pd layer and middle Ag layer, probably due to insufficient wetting during plating process. An on-site repair treatment in analogous to MOCVD (Metal-organic Chemical Vapor Deposition) process was first proposed to extend the lifetime of Pd-Ag membrane, i.e., by vaporizing, and subsequent decomposition of Ag(OOCC2F5) powders to "preferentially" block the pinholes under vacuum and at working temperature of ca. 473–673 K, which effectively reduced the N2 flux by 57.4% compared to the initial value. The H2 flux, however, declined by 16.7% due to carbon deposition on the membrane surface, which requires further investigation. This approach shows some potential for on-site repair without disassembly or cooling to room temperature. [ABSTRACT FROM AUTHOR]