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Chen, Jiming

Publications and source records attributed to Chen, Jiming.

Diffusion-assisted growth of periodic patterns on metal surfaces

Periodic patterns formed on various solid surfaces could seriously affect the properties of materials. Understanding the underlying mechanism is a key step to apply and control pattern formation in many fields. In this work, periodic patterns induced by low energy plasma exposures on tungsten surfaces are observed and related new formation mechanisms are developed. Results from experiments and computer simulations demonstrate that atom diffusion accelerated by low energy and high flux exposures is the dominant mechanism for pattern formation. Additionally, a similar pattern formation has been confirmed by plasma exposure experiments on molybdenum. Based on this mechanism, patterns with controllable size and shape have been successfully prepared on tungsten surface by adjusting plasma exposure parameters, which may provide a new understanding of pattern formation and related surface damage in tungsten induced by plasma exposures.

36 MATERIALS SCIENCE↗

The circular RNA circ-ITCH suppresses ovarian carcinoma progression through targeting miR-145/RASA1 signaling

Highlights: • A broad down-regulation of circ-ITCH and a worse prognosis were found in OC patients. • Circ-ITCH inhibits the cell viability and motility by CCK8, cell cycle, wound healing and invasion assay. • Circ-ITCH inhibits the tumorigenesis ability in xenograft NOD mice in vivo. • Circ-TCH acts as a ceRNA role of circ-ITCH through sponging miR-145 and up-regulation of RASA1 expression. As the leading cause of death for gynecological cancers, ovarian cancer (OC) ranks fifth overall for cancer-related death among women. Emerging evidence has indicated that circular RNA (circRNA), recognized as functional non-coding transcripts in eukaryotic cells, may be involved in many physiological or pathological processes. It was reported that circ-ITCH is downregulated in multi cancers and serves as a powerful tumor suppressor among through a competing endogenous RNA (ceRNA) pathway. However, the existence and the role of circ-ITCH in OC was not reported. Here, we found a broad down-regulation of circ-ITCH in OC tissues and cells, which correlates with a worse prognosis in OC patients. Functional studies suggest that circ-ITCH overexpression inhibits the cell viability and motility by CCK8, cell cycle, wound healing assay and invasion assay. It also inhibits the tumorigenesis ability in xenograft NOD mice in vivo. Mechanically, we demonstrated that circ-TCH acts as a ceRNA to sponge miR-145, increases the level of RASA1, and inhibits the malignant progression of OC cells via the circ-ITCH-miR-145-RASA1 axis in vitro and in vivo. Taken together, our findings provide a novel tumor suppressive role regarding circ-ITCH function in the malignant progression of OC.

60 APPLIED LIFE SCIENCES↗

Matminer: An open source toolkit for materials data mining

As materials data sets grow in size and scope, the role of data mining and statistical learning methods to analyze these materials data sets and build predictive models is becoming more important. This manuscript introduces matminer, an open-source, Python-based software platform to facilitate data-driven methods of analyzing and predicting materials properties. Matminer provides modules for retrieving large data sets from external databases such as the Materials Project, Citrination, Materials Data Facility, and Materials Platform for Data Science. It also provides implementations for an extensive library of feature extraction routines developed by the materials community, with 47 featurization classes that can generate thousands of individual descriptors and combine them into mathematical functions. Finally, matminer provides a visualization module for producing interactive, shareable plots. These functions are designed in a way that integrates closely with machine learning and data analysis packages already developed and in use by the Python data science community. We explain the structure and logic of matminer, provide a description of its various modules, and showcase several examples of how matminer can be used to collect data, reproduce data mining studies reported in the literature, and test new methodologies.

97 MATHEMATICS AND COMPUTING↗