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Xianwen Zhang

Publications and source records attributed to Xianwen Zhang.

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Dual-Correction Physics-Informed Neural Networks for Hemodynamic Reconstruction from Sparse Data

Quantifying hemodynamics in the curved segments of the intracranial internal carotid artery is a core challenge in diagnosing vascular stenosis. Conventional full-field imaging, such as 4D Flow MRI, is costly and difficult to widely promote. Meanwhile, reconstructing full-field fluid information from easily accessible and non-invasive sparse measurement data (such as transcranial Doppler ultrasound/computed tomography angiography) is essentially a highly challenging ill-posed inverse problem. To overcome the severe optimization difficulties and generalization failures of conventional physics-informed neural networks (PINNs) in highly tortuous geometries, we propose a dual-correction physics-informed neural network (DCP-INN) framework taking into account a causal decoupling strategy. The proposed DCP-INN model utilizes a diamond-shaped main network to capture low-frequency trends in physical evolution, and employs a parallel wide-deep correction network to compensate for high-frequency residuals resulting from complex geometric shapes. Furthermore, the framework introduces a high-order physical loss function based on Taylor expansion to enhance local continuity under extremely sparse data constraints. To validate the proposed method, we performed computational evaluations on realistic vascular geometries with significant tortuosity. The results demonstrate that the method effectively mitigates optimization challenges and significantly reduces flow field reconstruction error. This study not only achieves physically credible and robust flow field reconstruction in complex morphologies but also provides a highly promising algorithmic foundation for building low-cost, high-resolution personalized cardiovascular digital twins in future.

physics.med-ph

SOWAHA as a Cancer Suppressor Gene Influence Metabolic Reprogramming

SOWAHA is a protein-coding gene, also known as ANKRD43. Studies have indicated that SOWAHA can serve as a prognostic biomarker in colorectal cancer and pancreatic cancer. However, there are few reports about SOWAHA in other types of cancer and the specific mechanism of action of SOWAHA in cancer is also not clear. Based on National Center for Biotechnology Information (NCBI), The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression Project (GTEx), cBioPortal, Human Protein Atlas (HPA), etc., we adopted bioinformatics methods to uncover the potential tumor genomic features of SOWAHA, including the correlation with prognosis, gene mutation, immune cell infiltration, and DNA methylation in different tumors and evaluated the association with tumor heterogeneity, stemness, chemokines chemokine receptors, and immunomodulators in pan-cancer. Besides, we knocked down SOWAHA in SW620 cells and performed RNA-seq analysis, then we conducted functional enrichment to uncover the biological significance of the gene set. SOWAHA has early diagnostic potential, and low expression of SOWAHA was associated with poor prognosis in was associated with poor prognosis in GBMLGG, PAAD, READ, etc. SOWAHA is associated with most tumor immune-infiltrating cells in pan-cancer. SOWAHA correlates with DNA methylation, tumor heterogeneity, and stemness in many epithelial carcinomas. Furthermore, SOWAHA is involved in many enzyme activity and metabolic pathways, mainly metabolic programming pathways in cancer. Additionally, we identified two potential transcription factors of SOWAHA, TBX4, and FOXP2, which are dysregulated in SW620 cells. Besides, the cell proliferation and viability in siSOWAHA groups are better than in siNC groups.SOWAHA, identified as a suppressor gene, and its role in the progression of colorectal cancer is primarily mediated through metabolic reprogramming mechanisms.

q-bio.QM

Non-uniqueness of the transport equation at high spacial integrability

In this paper, we show the non-uniqueness of the weak solution in the class $ρ\in L^{s}_tL^p_x$ for the transport equation driven by a divergence-free vector field $\boldsymbol{u}\in L^{\tilde{s}}_tW^{1,q}_x\cap L_t^{s'}L_x^{p'}$ happens in the range $1/p+1/q>1-\frac{p-1}{4(p+1)p}$ with some $\tilde{s}>1$, as long as $1\le s<\infty$, $p>1$. As a corollary, $L^{\infty}$ in time of the density $ρ$ is critical in some sense for the uniqueness of weak solution. Our proof is based on the convex integration method developed in [Modena and Sattig, 2020, Ann. Inst. H. Poincaré C Anal. Non Linéaire], [Cheskidov and Luo, 2021, Ann. PDE].

math.AP