Search

Your search keyword '"Zhang, Meidi"' showing total 24 results
Start Over Author "Zhang, Meidi"
24 results on '"Zhang, Meidi"'

15. Single-Cell Transcriptomics Unveils the Dedifferentiation Mechanism of Lung Adenocarcinoma Stem Cells.

Author

Pan, Zhenhua, Zhang, Meidi, Zhang, Fengyu, Pan, Hongli, Li, Yongwen, Shao, Yi, Yuan, Xin, Wang, Ju, and Chen, Jun

Subjects
*CANCER stem cells, *STEM cells, *CELL populations, *THERAPEUTICS, *LUNGS, *PHENOTYPIC plasticity
Abstract

Lung adenocarcinoma (LUAD) is a major subtype of lung cancer, and its prognosis is still poor due to therapy resistance, metastasis, and recurrence. In recent years, increasing evidence has shown that the existence of lung cancer stem cells is responsible for the propagation, metastasis, therapy resistance, and recurrence of the tumor. During their transition to cancer stem cells, tumor cells need to inhibit cell differentiation and acquire invasive characteristics. However, our understanding of the property and role of such lung cancer stem cells is still limited. In this study, lung adenocarcinoma cancer stem cells (LCSCs) were enriched from the PC-9 cell line in a serum-free condition. PC-9 cells grew into spheres and showed higher survival rates when exposed to gefitinib: the drug used for the treatment of LUAD. Additionally, we found that the canonical stemness marker protein CD44 was significantly increased in the enriched LCSCs. Then, LCSCs were inoculated into the groin of nude mice for 1.5 months, and tumors were detected in the animals, indicating the strong stemness of the cells. After that, we performed single-cell RNA sequencing (scRNA-seq) on 7320 LCSCs and explored the changes in their transcriptomic signatures. We identified cell populations with a heterogeneous expression of cancer stem marker genes in LCSCs and subsets with different degrees of differentiation. Further analyses revealed that the activation of the FOXM1 (oncoprotein) transcription factor is a key factor in cell dedifferentiation, which enables tumor cells to acquire an epithelial-mesenchymal transition phenotype and increases the LCSC surface marker CD44. Moreover, we found that the combination of CD44, ABCG2, and ALCAM was a specific marker for LCSCs. In summary, this study identified the potential factors and molecular mechanisms underlying the stemness properties of LUAD cancer cells; it could also provide insight into developing novel and effective therapeutic approaches. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

17. Coordinated DMA: Improving the DRAM Access Efficiency for Matrix Multiplication

Author

Shenggang Chen, Zhang Meidi, Yang Guo, Zhong Liu, Zhiying Wang, Libo Huang, and Sheng Ma

Subjects
Random access memory, Hardware_MEMORYSTRUCTURES, Out-of-order execution, Computer science, Locality, Parallel computing, Memory controller, Partition (database), Matrix multiplication, Bottleneck, Computational Theory and Mathematics, Hardware and Architecture, Signal Processing, Dram, Dram memory
Abstract

High performance implementation of matrix multiplication is essential for scientific computing. The memory access procedure is quite possible to be the bottleneck of matrix multiplication. The widely used GotoBLAS GEMM implementation divides the integral matrix into several partitions to be assigned to different cores for parallelization. Traditionally, each core deploys a DMA transfer to access its own partition in the DRAM memory. However, deploying an independent DMA transfer for each core cannot efficiently exploit the inter-core locality. Also, multiple concurrent DMA transfers interfere with each other, further reducing the DRAM access efficiency. We observe that the same row of neighboring partitions is in the same DRAM page, which means that there is significant locality inherent in the address layout. We propose the coordinated DMA to efficiently exploit the locality. It invokes one transfer to serve all cores and moves data in a row-major manner to improve the DRAM access efficiency. Compared with a baseline design, the coordinated DMA improves the bandwidth by 84.8 percent and reduces DRAM energy consumption by 43.1 percent for micro-benchmarks. It achieves higher performance for the GEMM and Linpack benchmark. With much less hardware costs, the coordinated DMA significantly outperforms an out-of-order memory controller.

Published
2019

24. Geochemical exploration in thick transported overburden, Eastern China

Author

Jin Jun, Hu Zhengqing, Sun Xiangli, Zhang Maozhong, and Zhang Meidi

Subjects
Overburden, Mining engineering, Geochemistry and Petrology, Eastern china, Prospecting, Economic Geology, Extraction methods, Geology
Abstract

Experiments on the effectiveness of geochemical methods of prospecting have been carried out in the thick transported overburden of different environments of Eastern China. Studies have also been made on the partial extraction methods and the formation mechanism of secondary epigenetic geochemical anomalies. In this paper, the authors introduce some experimental results of the different methods and evaluate the effectiveness and the problems of these methods in different environments in Eastern China.

Published
1989

Catalog

Books, media, physical & digital resources
See catalog results