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Xiaoxue Fan

Publications and source records attributed to Xiaoxue Fan.

4 recordsLinked to original sources

An AI-driven robotic system for two-dimensional hetero-assemblies

Nanomaterials stacked on-demand, such as rotationally assembled two-dimensional (2D) van der Waals (vdW) layered compounds, provides a versatile platform for quantum simulation and the exploration of exotic electronic phases. Currently, however, such nanoassemblies remain largely confined to inefficiency, manually operated process, limiting their potential for probing emergent physical phenomena. There is a pressing need in the field for high-precision, automated assembling techniques, especially for the scalable fabrication of 2D twistronic heterostructures. Here, we present an intelligent automation system dedicated to the fabrication of van der Waals stacks, following the state-of-the-art protocol for dry transfer of exfoliated 2D materials. The system further employs metadata generated from each automated stacking procedure to perform reinforcement learning, thereby continuously bettering its performances. As a concrete demonstration, we fabricate twisted bilayer graphene (TBLG) -- known for its challenging preparation -- and exhibit its unconventional superconductivity near the magic angle. Our work may pave the way for high-throughput fabrication of low-dimensional nanomaterials including twistronic heterostructures, where integrating data mining and artificial intelligence can accelerate the discovery of novel physical phenomena.

cond-mat.mes-hall

Batch-Fabricated PDMS Templates for the Robotic Transfer of 2D Materials

Robotic stacking of van der Waals heterostructures has been at the verge thanks to the convergence between artificial intelligence (AI) and two-dimensional (2D) materials research. Key ingredients to fulfill this pursuit often include algorithms to identify layer compounds on chips, hard-wares to realize sophisticated operations of motion and/or rotation in a microscale, and, as importantly, highly-standardized and uniform transfer stamps that are often used in picking up layered materials under a microscope. Here, we report a hot-casted-droplet batch fabrication method for polydimethylsiloxane (PDMS) templates tailored for dry transfer of 2D materials. Controlled precursor formulation, degassing, and motorized-syringe dispensing produce dome-shaped PDMS templates with ultra-smooth surfaces (root-mean-square roughness about 0.3 nm at relatively low curing temperatures). By tuning the curing temperature, the reproducible and controllable apex curvature allows precisely defined contact area between the organic adhesive film and substrate, via thermal expansion. Our results further reveals thermalmechanical behaviors with different casting parameters of such PDMS domes. This scalable and parameterized fabrication protocol gives rise to uniform transfer-stamps with ultra-smooth surface, which may be beneficial for future AI-driven robotic assembly of 2D material heterostructures.

cond-mat.mtrl-sci

Pharmacokinetic characteristics of Jinhong tablets in normal, chronic superficial gastritis and intestinal microbial disorder rats

Jinhong tablet (JHT), a traditional Chinese medicine made from four herbs, effectively treats chronic superficial gastritis (CSG) by soothing the liver, relieving depression, regulating qi, and promoting blood circulation. However, its pharmacokinetics are underexplored. This study investigates JHT's pharmacokinetics in normal rats and its differences in normal, CSG, and intestinal microbial disorder rats. A quantitative method for seven active ingredients in rat plasma was established using UPLC-TQ-MS/MS. After administering various JHT doses, plasma concentrations were measured to assess pharmacokinetics in normal rats. The pharmacokinetics of four main ingredients were compared in normal, CSG, and fecal microbiota transplantation (FMT) rats. Intestinal microbial changes were evaluated by high-throughput sequencing. Spearman correlation analysis linked ingredient exposure to gut microbiota disturbances. The method showed good linearity, precision, accuracy, extraction recovery, and stability. In normal rats, all seven ingredients were rapidly absorbed. Tetrahydropalmatine, corydaline, costunolide, and rhamnosylvitexin had good exposure, while dehydrocorydaline, allocryptopine, and palmatine hydrochloride had low exposure. Tetrahydropalmatine, corydaline, and costunolide followed linear pharmacokinetics (AUC0-t, Cmax) at doses of 0.7-5.6 g/kg, while rhamnosylvitexin and dehydrocorydaline showed linearity at 0.7-2.8 g/kg. In CSG and FMT rats, pharmacokinetic differences were observed. CSG enhanced costunolide exposure and Cmax, and increased rhamnosylvitexin exposure. FMT raised corydaline exposure and rhamnosylvitexin Cmax, linked to 20 bacterial genera.

q-bio.QM

Integrating network pharmacology, metabolomics, and gut microbiota analysis to explore the effects of Jinhong tablets on chronic superficial gastritis

Chronic superficial gastritis (CSG) severely affects quality of life and can progress to worse gastric pathologies. Traditional Chinese Medicine (TCM) effectively treats CSG, as exemplified by Jinhong Tablets (JHT) with known anti-inflammatory properties, though their mechanism remains unclear. This study integrated network pharmacology, untargeted metabolomics, and gut microbiota analyses to investigate how JHT alleviates CSG. A rat CSG model was established and evaluated via H&E staining. We identified JHT's target profiles and constructed a multi-layer biomolecular network. Differential metabolites in plasma were determined by untargeted metabolomics, and gut microbiota diversity/composition in fecal and cecal samples was assessed via 16S rRNA sequencing. JHT markedly reduced gastric inflammation. Network pharmacology highlighted metabolic pathways, particularly lipid and nitric oxide metabolism, as essential to JHT's therapeutic effect. Metabolomics identified key differential metabolites including betaine (enhancing gut microbiota), phospholipids, and citrulline (indicating severity of CSG). Pathway enrichment supported the gut microbiota's involvement. Further microbiota analysis showed that JHT increased betaine abundance, improved short-chain fatty acid production, and elevated Faecalibaculum and Bifidobacterium, thereby alleviating gastric inflammation. In conclusion, JHT alleviates CSG via diverse metabolic processes, especially lipid and energy metabolism, and influences metabolites like betaine alongside gut microbes such as Faecalibaculum and Bifidobacterium. These findings underscore JHT's therapeutic potential and deepen our understanding of TCM's role in CSG management.

q-bio.MN