Biology subjects

Xi, M.

Publications and source records attributed to Xi, M..

3 recordsLinked to original sources

bioRxiv2024

A method for recognizing motor imagery EEG signals based on high-quality lead selection

In the application of motor imagery brain-computer interface system, high-density leads bring redundant noise, which leads to time-consuming system operation and poor performance. A channel selection strategy based on brain function network is proposed. This method introduces Synchronization likelihood was used as a connection index to construct a motor imagery brain functional network, and the centrality analysis of the constructed network was used to select the combination of strong motor-related leads. Experiments were carried out on the EEG datasets dataset IVa of the 3rd International Brain-Computer Interface Competition and dataset I of the 4th International Brain-Computer Interface Competition, and 27 high-quality channels were selected from the 118 channels of dataset IVa, as well as 16 high-quality channels were selected from the 59 channels of dataset I. Finally, the CSP algorithm and support vector machine are used to extract features and classify. The experimental results show that the proposed channel selection strategy can greatly reduce the number of channels while obtaining higher recognition accuracy, which verifies the practicability and effectiveness of the proposed method.

bioengineering↗

bioRxiv2023

Linking root-associated fungal and bacterial functions to root economics

Tree roots form symbioses with soil microbes to acquire nutrients, but the relationships between root nutrient acquisition strategies and microbial community composition remain poorly understood. Here, we measured root traits and root-associated fungal and bacterial guilds in 336 trees of 52 species from a subtropical forest. We found a fungal gradient from ectomycorrhizal to saprotrophic dominance, which corresponded with a shift from organic to mineral nutrient economics. This fungal gradient was aligned with the increase of root nitrogen concentration, suggesting a linkage from simple root trait to fungal-mediated carbon-nutrient cycling. We also found that the functional composition of fungal and bacterial communities was closely correlated with host root-zone pH, which often varied among coexisting trees. Root-zone pH was independent of the common root traits, underpinning a potential new gradient in the root trait space. Our findings integrate microbial functions into the root economics framework, thereby advancing the understanding of diversity of nutrient acquisition strategies across forest trees.

ecology↗

bioRxiv2022

Arbuscular mycorrhizal fungal composition across US citrus orchards, management strategies, and disease severity spectrum

Arbuscular mycorrhizal fungi (AMF) remain understudied in perennial cropping systems. Citrus is a globally grown fruit tree and under threat by the pandemic Huanglongbing (HLB) disease. Here, we assessed in what capacity geographical location, management strategies and disease affect AMF citrus root communities. Root samples were collected from 88 trees in ten orchards located in the two major citrus producing states in the US. Orchards were selected based on conventional or organic practices in California and based on HLB symptom severity in Florida. We used AMF-specific amplicon sequencing primers to capture community composition and diversity. Taxa names were assigned based on a phylogenetic analysis that comprised a backbone of AMF references sequences from Mycobank and virtual taxa from the MaarjAM database. AMF were detected in 78% of citrus root samples with taxa belonging to six known (Dominikia, Funneliformis, Glomus, Rhizophagus, Sclerocystis, Septoglomus) and unknown Glomeraceae genera. Geographical location affected AMF community composition but not richness, whereas management practice and disease influenced both richness and composition. Our approach indicated that perennial agroecosystems share a set of AMF generalist and specialist taxa. Some taxa could improve environmental fitness and be exploited for agricultural purposes.

microbiology↗