Dan Chen

Prof. Dan Chen


Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 September 2020 in BioData Mining
Verified
Journal Article
Open access
PDF file
DCDan Chen
Dan Chen
JHJun Hu
Jun Hu
MZMei Zhu
Mei Zhu
Niansheng TangNiansheng Tang
Niansheng Tang
YYYang Yang
Yang Yang
YFYuran Feng
Yuran Feng
Background: Various combinations of ultrasonographic (US) characteristics are increasingly utilized to classify thyroid nodules. But they lack theories, and heavily depend on radiologists’ experience, and cannot correctly classify thyroid nodules. Hence, our main purpose of this manuscript is to select the US characteristics significantly associated with malignancy and to develop an efficient scoring system for facilitating ultrasonic clinicians to correctly identify thyroid malignancy.Methods: A logistic regression (LR) model is utilized to identify the potential thyroid malignancy, and the least absolute shrinkage and selection operator (LASSO) method is adopted to simultaneously select US characteristics significantly associated with malignancy and estimate parameters in LR model. Based on the selected US characteristics, we calculate the probability for each of thyroid nodules via random forest (RF) and extreme learning machine (ELM), and develop a scoring system to classify thyroid nodules. For comparison, we also consider eight state-of-the-art methods such as support vector machine (SVM), neural network (NET), etc. The area under the receiver operating characteristic curve (AUC) is employed to measure the accuracy of various classifiers.Results: The US characteristics: nodule size, AP/T≥1, solid component, micro-calcifications, hackly border, hypoechogenicity, presence of halo, unclear border, irregular margin, and central vascularity are selected as the significant predictors associated with thyroid malignancy via the LASSO LR (LLR). Using the developed scoring system, thyroid nodules are classified into the following four categories: benign, low suspicion, intermediate suspicion, and high suspicion, whose rates of malignancy correctly identified for RF (ELM) method on the testing dataset are 0.0% (4.3%), 14.3% (50.0%), 58.1% (59.1%) and 96.1% (97.7%), respectively.Conclusion: LLR together with RF performs better than other methods in identifying malignancy, especially for abnormal nodules, in terms of risk scores. The developed scoring system can well predict the risk of malignancy and guide medical doctors to make management decisions for reducing the number of unnecessary biopsies for benign nodules.

27 March 2025 in Mathematics
Verified
Journal Article
Open access
PDF file
JNJie Niu
Jie Niu
RHRunqi He
Runqi He
QZQiyao Zhou
Qiyao Zhou
WLWenjing Li
Wenjing Li
RJRuxian Jiang
Ruxian Jiang
DCDan Chen
Dan Chen
In the data-driven healthcare sector, balancing privacy protection and model performance is critical. This paper enhances accuracy and reliability in survival analysis by integrating differential privacy, deep learning, and the Cox proportional hazards model within a federated learning framework. Traditionally, differential privacy’s noise injection often degrades model performance. To address this, we propose two adaptive privacy budget allocation strategies considering weight changes across neural network layers. The first, LS-ADP, utilizes layer sensitivity to assess the influence of individual layer weights on model performance and develops an adaptive differential privacy algorithm. The second, ROW-DP, comprehensively assesses weight variations and absolute values to propose a random one-layer weighted differential privacy algorithm. These algorithms provide differentiated privacy protection for various weights, mitigating privacy leakage while ensuring model performance. Experimental results on simulated and clinical datasets demonstrate improved predictive performance and robust privacy protection.

20 December 2012 in HEREDITAS
Verified
Journal Article
Closed access
HLHuimin Li
Huimin Li
DCDan Chen
Dan Chen
Previous studies from oligonucleotides in the ribosomal protein (RP) genes of the yeast and fruitfly indicated that the potential transcriptional regulatory sites are located in the introns of the genes. The transcriptional regulatory sites in introns are still poorly understood. To explore the functional significance of transcriptional regulation of introns, we extracted over-represented oligonucleotides (also known as motifs) in the first introns of the human and mouse ribosomal protein genes by statistical comparative analysis, and found that over 85% of these oligonucleotides were consistent with the known transcriptional factor binding sites, which might be potential transcriptional regulatory elements. By analyzing the base compositions of these elements, we found that a majority (>95%) of the detected motifs were rich in C and G and only a few of them were rich in A and T. Moreover, the oligonucleotides were close to the 5'-ends of the first introns (the distances between the motifs and the transcriptional start sites or upstream regions of genes are short). We speculated that the properties of over-represented motifs in the first introns might be associated with the transcriptional control.