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Tianbo Xu

Publications and source records attributed to Tianbo Xu.

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Individualized prescriptive inference in ischaemic stroke

The gold standard in the treatment of ischaemic stroke is set by evidence from randomized controlled trials, based on simple descriptions of presumptively homogeneous populations. Yet the manifest complexity of the brain's functional, connective, and vascular architectures introduces heterogeneities that violate the underlying statistical premisses, potentially leading to substantial errors at both individual and population levels. The counterfactual nature of interventional inference renders quantifying the impact of this defect difficult. Here we conduct a comprehensive series of semi-synthetic, biologically plausible, virtual interventional trials across 100M+ distinct simulations. We generate empirically grounded virtual trial data from large-scale meta-analytic connective, functional, genetic expression, and receptor distribution data, with high-resolution maps of 4K+ acute ischaemic lesions. Within each trial, we estimate treatment effects using models varying in complexity, in the presence of increasingly confounded outcomes and noisy treatment responses. Individualized prescriptions inferred from simple models, fitted to unconfounded data, were less accurate than those from complex models, fitted to confounded data. Our results indicate that complex modelling with richly represented lesion data is critical to individualized prescriptive inference in ischaemic stroke.

q-bio.QM

Generalizable automated ischaemic stroke lesion segmentation with vision transformers

Ischaemic stroke, a leading cause of death and disability, critically relies on neuroimaging for characterising the anatomical pattern of injury. Diffusion-weighted imaging (DWI) provides the highest expressivity in ischemic stroke but poses substantial challenges for automated lesion segmentation: susceptibility artefacts, morphological heterogeneity, age-related comorbidities, time-dependent signal dynamics, instrumental variability, and limited labelled data. Current U-Net-based models therefore underperform, a problem accentuated by inadequate evaluation metrics that focus on mean performance, neglecting anatomical, subpopulation, and acquisition-dependent variability. Here, we present a high-performance DWI lesion segmentation tool addressing these challenges through optimized vision transformer-based architectures, integration of 3563 annotated lesions from multi-site data, and algorithmic enhancements, achieving state-of-the-art results. We further propose a novel evaluative framework assessing model fidelity, equity (across demographics and lesion subtypes), anatomical precision, and robustness to instrumental variability, promoting clinical and research utility. This work advances stroke imaging by reconciling model expressivity with domain-specific challenges and redefining performance benchmarks to prioritize equity and generalizability, critical for personalized medicine and mechanistic research.

eess.IV

I2C Management Based on IPbus

CBM (Compressed Baryonic Matter) is mainly used to study QCD phase diagram of strong interactions in high and moderate temperature region. Before the next generation GBTx based CBM DAQ system is built up, the DPB (Data Processing Board) layer is used in data readout and data pre-processing, where a general FPGA FMC carrier board named AFCK is used. This paper mainly describes the management of the Inter-integrated Circuit (I2C) devices on AFCK and the FMCs it carries via IPBus, an FPGA-based slow control bus used in CBM DAQ system. On AFCK, the connection of IPBus depends on the correct initialization of a set of I2C devices, including the I2C-bus multiplexer (choosing correct I2C bus), the clock crosspoint switch (providing the 125MHz needed by 1000BASE-X/SGMII), the serial EEPROM with a EUI-48 address (providing the AFCK MAC address). An independent initial module can execute an I2C command sequence stored in a ROM, through which the FPGA can write to/read from the I2C devices without IPBus, so that the related I2C devices are correctly initialized and the necessary preparation for the IPBus start-up is fulfilled. After the initialization, a Wishbone I2C master core is used as an IPbus slave and all other I2C devices can be configured directly via IPBus. All the design has been fully tested in the CBM DPB design.

physics.ins-det

The Electronics Design of Error Field Feedback Control System in KTX

KTX (Keda Tours eXperiment) is a new RFP (reversed field pinch) device at the University of Science and Technology of China. The unique double-C design of the KTX makes modifications and investigations of power and particle control easy, but the error field of slit zone in the new design should not be neglected. The objective of this paper is to introduce a new active feedback control system which can change the voltage between the unique double-C structures to make the toroidal field better. FPGA is the central part of the whole system to control all the process, because it can manipulate and transmit the data from coils in real time. There are 2 high-speed 8-channels ADCs in the system to convert the analog signal from 16 Rogowski coils which can detect dynamic eddy current of copper shells near the vertical gap. FPGA also control the external power amplifier to change the voltage between the unique double-C structures by commanding 16 high-speed DACs to give the RFP device a feedback. Result indicated that the error field in KTX device was reduced, and the system could successfully achieve fast matrix calculation with lower delay.

eess.SP