Cleavage Furrow Formation for Avascular Tumor Growth based on Finite Element Modeling

Changyu Liu,Dapeng Li,Bin Lu,Tiezhu Zhao 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.3

A number of studies have shown that the prevention and cure of malignant tumors may become much easier if growth mechanisms, such as the role of cleavage furrow formation in tumor cell division, could be discovered and understood in the earlier avascular phase. Although it is well known that metazoan mitotic spindle which is one of the most important substances during the cytokinesis of a cell division determines the position of the cleavage furrow formation, we are still on the verge of solving the puzzle of what molecules and how they control the formation of the cleavage furrow. In this paper, we propose a cleavage furrow formation approach based on finite element method, which combines nodes selection, mesh partition and matrix assembly in a total energy equation, for modeling the mechanisms of avascular tumor growth. We also perform several experiments. Results show that, by using our proposed approach for the avascular tumor growth, the positions of cleavage furrows are decided not only chemically but also physically and tumor cells are not symmetric, which demonstrates the effectiveness of our proposed approach.

Combing Customizable Configuration and Interactive Control to Simulate Juicing and Filling Production Line

Changyu Liu,Dapeng Li,Bin Lu,Tiezhu Zhao 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.5

Both the rapid growth of global economy and the rapid improvement in living conditions have witnessed an explosive requirement of foods that are rich of vitamin. Juice beverage, as one kind of these foods, is very popular among people of all ages due to its higher portability and easier preservability. However, there are many issues, such as a very low device utilization rate, a very long design period and an inflexible manufacturing process, by using the traditional juicing and filling production line. The introduction of virtual reality simulation technologies can not only detect bottlenecks of the production line during design period, but also process fruits according to seasons for improving the total efficiency of one single production line. In this paper, we combine customizable configuration and interactive control to design and implement a simulation system of juicing and filling production line based on the traditional client-server architecture. Practical applications show that the developed simulation system can not only shorten effectively the design period but also improve greatly the design quality.

Dual Focusing Ultrasonic Imaging Algorithm Based on Chirp-Coded and Adaptive Beamforming Combination

WANG Linhong,Gao Yang,Li Na,YU Tiezhu 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.7

According to the inherent deficiency of traditional beamformer on anti-noise and lateral resolution, this paper proposes a method based on the combination of Chirp-coded and adaptive dual focusing beamformer (CARDFB). Firstly, Chirp-coded technology is introduced to improve the transmitting average power, and then the dual focusing beamformer and adaptive beamformer are combined to obtain a higher quality beamforming signal. Finally, the signal filtered with matched filter is used for imaging. Experimental results indicate that the proposed CARDFB algorithm can achieve higher lateral resolution, better main-to-side lobe ratio and are more robust to noise compared with traditional dynamic focusing combined with adaptive focusing beamformer.

Succession of the Nanoplankton Community during a Brown Tide in a Scallop Culture Area in China

Ling Qiao,Jie Yu,Ying Li,Haobing Guo,Yu Zhen,Lingling Zhang,Tiezhu Mi,Fuchong Zhang,Zhenmin Bao 한국해양과학기술원 2019 Ocean science journal Vol.54 No.3

Brown tides caused by Aureococcus anophagefferens have occurred frequently in the coastal waters of Qinhuangdao since 2009. The Changli coast is the area most strongly affected by the brown tides, which result in significant economic losses and serious ecological harm. To understand the effects of brown tides on nanoplankton diversity and biomass, samples were collected from May to July in 2012 at station XKK, which is approximately 0.2 nautical miles off the Changli coast. The V9 region of the 18S rDNA gene was used as a marker and was analyzed by Illumina sequencing to assess the nanoplankton diversity and biomass, and real-time fluorescence quantitative PCR was performed to analyze the temporal variations in the copy concentrations of the 18S rDNA of nanoplankton. The results showed that nanoplankton diversity, as determined by the Shannon index, decreased from May to June and increased in July. Illumina sequencing analysis revealed that the plankton community differed among the samples from May to July, and over this period, the dominant phytoplankton groups changed from pelagophytes to chlorophytes. Sufficient nutrients and low grazing pressure by zooplankton and scallops accelerated the growth of small-celled phytoplankton. A. anophagefferens was the most dominant phytoplankton species, with an 18S rDNA maximum copy concentration detected on 26 June, followed by Micromonas sp. and Bathycoccus prasinos, with maximum copy concentrations observed on 3 July. Ciliophora, Arthropoda and Cercozoa were the dominant taxa of the local zooplankton community. The Ciliophora and Arthropoda biomasses decreased, and the Cercozoa biomass increased when the copy concentration of A. anophagefferens peaked on 26 June. We suspect that A. anophagefferens had a significantly negative effect on the growth of Ciliophora and Arthropoda and could be ingested by Cercozoa to promote its proliferation. The small and low-abundance plankton that are likely missed in microscopic and clone library analyses could be detected using Illumina sequencing and qPCR, which provide an effective method for a comprehensive analysis of the plankton community.

Differences in the methanogen community between the nearshore and offshore sediments of the South Yellow Sea

Chen Ye,Zhen Yu,Wan Jili,Yin Xia,Li Siqi,Liu Jiayin,Zhang Guodong,Mi Tiezhu 한국미생물학회 2022 The journal of microbiology Vol.60 No.8

The differences in methanogen abundance and community composition were investigated between nearshore and offshore sediments in the South Yellow Sea (SYS). Shannon, Simpson, and Chao1 indices revealed a higher diversity of methanogens in the nearshore sediments than in the offshore sediments. The Mann–Whitney U test demonstrated that the relative abundance of Methanococcoides was significantly higher in the offshore sediments, while the relative abundances of Methanogenium, Methanosarcina, Methanosaeta, Methanolinea, and Methanomassiliicoccus were significantly higher in the nearshore sediments (P < 0.05). The abundance of the mcrA gene in the nearshore sediments was significantly higher than that in the offshore sediments. Furthermore, a similar vertical distribution of the methanogen and sulfatereducing bacteria (SRB) abundances was observed in the SYS sediments, implying there is potential cooperation between these two functional microbes in this environment. Finally, total organic carbon (TOC) was significantly correlated with methanogen community composition.

Transferability of a Visible and Near-Infrared Model for Soil Organic Matter Estimation in Riparian Landscapes

Yaolin Liu,Qinghu Jiang,Teng Fei,Junjie Wang,Tiezhu Shi,Kai Guo,Xiran Li,Yiyun Chen 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Computational and experimental characterization of estrogenic activities of 20(S, R)-protopanaxadiol and 20(S, R)-protopanaxatriol

Tiehua Zhang,Shuning Zhong,Ligang Hou,Yongjun Wang,XiaoJia Xing,Tianzhu Guan,Jie Zhang,Tiezhu Li 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.5

Background: As the main metabolites of ginsenosides, 20(S, R)-protopanaxadiol [PPD(S, R)] and 20(S, R)-protopanaxatriol [PPT(S, R)] are the structural basis response to a series of pharmacological effects of their parent components. Although the estrogenicity of several ginsenosides has been confirmed, however, the underlying mechanisms of their estrogenic effects are still largely unclear. In this work, PPD(S, R) and PPT(S, R) were assessed for their ability to bind and activate human estrogen receptor α(hERα) by a combination of in vitro and in silico analysis. Methods: The recombinant hERα ligand-binding domain (hERa-LBD) was expressed in E. coli strain. The direct binding interactions of ginsenosides with hERα-LBD and their ERα agonistic potency were investigated by fluorescence polarization and reporter gene assays, respectively. Then, molecular dynamics simulations were carried out to simulate the binding modes between ginsenosides and hERα-LBD to reveal the structural basis for their agonist activities toward receptor. Results: Fluorescence polarization assay revealed that PPD(S, R) and PPT(S, R) could bind to hERα-LBD with moderate affinities. In the dual luciferase reporter assay using transiently transfected MCF-7 cells, PPD(S, R) and PPT(S, R) acted as agonists of hERα. Molecular docking results showed that these ginsenosides adopted an agonist conformation in the flexible hydrophobic ligand-binding pocket. The stereostructure of C-20 hydroxyl group and the presence of C-6 hydroxyl group exerted significant influence on the hydrogen bond network and steric hindrance, respectively. Conclusion: This work may provide insight into the chemical and pharmacological screening of novel therapeutic agents from ginsenosides.