Effect of Blending Modifications for Phenylethynyl-terminated Polyimides

Ping Yu,Min-zhao Xue,Yan-gang Liu,Xue Yang,Li-jing Pan,Yan-li Zhang,Wei Wang 한국섬유공학회 2020 Fibers and polymers Vol.21 No.2

A reactive diluent (ODA-PEPA) and a flexible phenylethynyl-terminated imide oligomer (PEI-PEPA) were designed and synthesized based on the 2,3,3',4'-diphenyl ether tetracarboxylic acid dianhydride (a-ODPA), 3,4'-oxydianiline(3,4'-ODA), and 4-phenylethynylphthalic anhydride (PEPA). Solution blended systems with the addition of 5, 10, and 15 wt% ODA-PEPA to PEI-PEPA oligomer and their cured resin systems were prepared. Results showed that ODA-PEPA is semi-crystalline in nature. The Tg values of cured resins were improved from 273 oC to 280 oC by the addition of ODA-PEPA, due to the higher crosslink densities. In addition, rheological properties of blends showed lower melt viscosity and wider processing window, revealing improved melt processabilities for potential application in making advanced composites. The isothermal viscosity in 280 oC of PEI-PEPA containing 15 wt% ODA-PEPA reactive diluent decreased by two thirds, due to the low molecular weight of ODA-PEPA. The cured blends demonstrated high thermal stability and heat resistance. 5 wt% thermal decomposition temperatures (Td5) of the cured blends were above 549 oC and 547 oC in N2 and air atmosphere, respectively. The char yield reported at 800 oC in N2 atmosphere increased from 58.8% to 63.7 % with the addition of ODAPEPA. Meanwhile, the cured polyimides blends possessed good bond strength (> 9.3 MPa).

Calcineurin-Responsive Transcription Factor CgCrzA Is Required for Cell Wall Integrity and Infection-Related Morphogenesis in Colletotrichum gloeosporioides

Ping Wang,Bing Li,Yu-Ting Pan,Yun-Zhao Zhang,De-Wei Li,Lin Huang 한국식물병리학회 2020 Plant Pathology Journal Vol.36 No.5

The ascomycete fungus Colletotrichum gloeosporioides infects a wide range of plant hosts and causes enormous economic losses in the world. The transcription factors (TFs) play an important role in development and pathogenicity of many organisms. In this study, we found that the C2H2 TF CgCrzA is localized in both cytoplasm and nucleus under standard condition, and it translocated from cytoplasm to nucleus in a calcineurin- dependent manner. Moreover, the ΔCgCrzA was hypersensitive to cell wall perturbing agents and showed severe cell wall integrity defects. Deletion of the CgCRZA inhibited the development of invasive structures and lost pathogenicity to plant hosts. Our results suggested that calcineurin-responsive TF CgCrzA was not only involved in regulating cell wall integrity, but also in morphogenesis and virulence in C. gloeosporioides.

Multi-method mercury specification from lignite-fired power plants

Ping Lu,Jiang Wu,Wei-ping Pan 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.2

Mercury concentration and speciation partitioning, including total mercury, elemental mercury and oxidized mercury from a lignite-fired power plant under different operating conditions, was studied by Ontario hydro method (OHM), two kinds of continuous mercury monitors (semi-continuous emission monitor (SCEM) and continuous mercury monitor (CMM)), and the sorbent trap method. The effects of boiler load, fuel blending ratio, electrostatic precipitator, flue gas desulphurization, flue gas bypassing the FGD ratio, and mercury measuring methods on mercury emission were analyzed. The results indicated that mercury data from OHM, SCEM and CMM presented a good consistency throughout the entire testing period within ±20% acceptable range; however, the results from Appendix K provided bigger discrepancies than the results of OHM and SCEM due to the interferences of higher selenium content in the flue gas. The particulate-bound mercury removal efficiencies of ESP were determined to be 16-35%. The percentages of elemental mercury emitted from two lignite-fired power plants were in the higher ranges of 43.9-74.2%.

Knockdown of glycogen phosphorylase and glycogen synthase influences expression of chitin synthesis genes of rice brown planthopper Nilaparvata lugens

Dao-Wei Zhang,Hui-Juan Wang,Xing Jin,Bi-Ying Pan,Bo-Ping Zeng,Zhong-Jiu Xiao,Cai-Di Xu,Bin Tang 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

Glycogen synthase (GS) and glycogen phosphorylase (GP) are two key enzymes in the glycogen synthesis pathway, which catalyze trehalose and glucose transformation in insects. GS and GP can be regulated by trehalose metabolism, which plays an important role in insect growth. However, it is not known whether these genes can be targeted for pest control through regulation of chitin metabolism. We studied the function of Nilaparvata lugens GS and GP (NLGS and NLGP, respectively) using RNA interference, and reported that trehalose and the chitin biosynthesis pathways are regulated by GP and GS, especially TPS3, TRE1-1, and G6PI1, which decreased following knockdown of these two genes. The expression levels of TPS1, TPS2, and several chitin synthesis pathway family genes were significantly increased following dsNlGP injection. Additionally, despite there being no apparent change to the chitin content, an abnormal molting phenotype and wing deformity appeared, and close to 25% insects died. These results demonstrate that silencing of NLGP or NLGS can lead to molting deformities and an elevated mortality rate through the regulation of chitin pathway genes and chitinase genes. NLGP may play a key role in chitin synthesis due to the number of genes regulated, and higher deformity and mortality rates resulting from its knockdown.

DICOM-Based Multi-Center Electronic Medical Records Management System

Jui-Hung Kao,Chien-Yeh Hsu,Yu-Ping Sung,Wei-Pan Liao 보안공학연구지원센터 2010 International Journal of Bio-Science and Bio-Techn Vol.2 No.2

In Vitro and In Vivo Study on the Effect of Lysosome-associated Protein Transmembrane 4 Beta on the Progression of Breast Cancer

Deyou Tao,Junqing Liang,Yihong Pan,Yanting Zhou,Ying Feng,Lin Zhang,Jingjing Xu,Hui Wang,Ping He,Jie Yao,Yang Zhao,Qinjie Ning,Wen Wang,Wei Jiang,Jing Zheng,Xia Wu 한국유방암학회 2019 Journal of breast cancer Vol.22 No.3

Purpose: Although the effect of lysosome-associated protein transmembrane 4 beta (LAPTM4B) on the proliferation, migration, and invasion of breast cancer (BC) cells has already been studied, its specific role in BC progression is still elusive. Here, we evaluated the effect of different levels of LAPTM4B expression on the proliferation, invasion, adhesion, and tumor formation abilities of BC cells in vitro, as well as on breast tumor progression in vivo. Methods: We investigated the influence of LAPTM4B expression on MCF-7 cell proliferation, invasion, adhesion, and tube formation abilities in vitro through its overexpression or knockdown and on breast tumor progression in vivo. Results: Cell growth curves and colony formation assays showed that LAPTM4B promoted the proliferation of breast tumor cells. Cell cycle analysis results revealed that LAPTM4B promoted the entry of cells from the G1 into the S phase. Transwell invasion and cell extracellular matrix adhesion assays showed that LAPTM4B overexpression increased the invasion and adhesion capabilities of MCF-7 cells. More branches were observed in MCF-7 cells overexpressing LAPTM4B under an electron microscope. In comparison with LAPTM4B overexpression, LAPTM4B knockdown decreased the expression of vascular endothelial growth factor-A and significantly inhibited the vasculogenic tube formation ability of tumors. These results were also verified with western blot analysis. Conclusion: LAPTM4B promoted the proliferation of MCF-7 cells through the downregulation of p21 (WAF1/CIP1) and caspase-3, and induced cell invasion, adhesion, and angiogenesis through the upregulation of hypoxia-inducible factor 1 alpha, matrix metalloproteinase 2 (MMP2), and MMP9 expression. This specific role deems LAPTM4B as a potential therapeutic target for BC treatment.

Suppression of CDK2 expression by siRNA induces cell cycle arrest and cell proliferation inhibition in human cancer cells

( Xiang E Long ),( Zhao Hui Gong ),( Lin Pan ),( Zhi Wei Zhong ),( Yan Ping Le ),( Qiong Liu ),( Jun Ming Guo ),( Jiu Chang Zhong ) 한국생화학분자생물학회 (구 한국생화학회) 2010 BMB Reports Vol.43 No.4

Cyclin-dependent kinase 2 (CDK2) is a member of serine/threonine protein kinases, which initiates the principal transitions of the eukaryotic cell cycle and is a promising target for cancer therapy. The present study was designed to inhibit cdk2 gene expression to induce cell cycle arrest and cell proliferation suppression. Here, we constructed a series of RNA interference (RNAi) plasmids which can successfully express small interference RNA (siRNA) in the transfected human cells. The results showed that the RNAi plasmids containing the coding sequences for siRNAs down-regulated the cdk2 gene expression in human cancer cells at the mRNA and the protein levels. Furthermore, we found that the cell cycle was arrested at G0G1 phases and the cell proliferation was inhibited by different siRNAs. These results demonstrate that suppression of CDK2 activity by RNAi may be an effective strategy for gene therapy in human cancers. [BMB reports 2010; 43(4): 291-296]

Impurity Behaviors under Wall Conditioning in HL-2A

Zhengying Cui,Chenghe Cui,Mingxu Wang,Ping Sun,Quanming Wang,Wei Li,Yudong Pan,Zeng Cao 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III

Impurities are one of the key issues of tokamak plasma research, as they are directly related to plasma quality and steady-state operation. The HL-2A device with two close divertor is the first divertor tokamak in China. It was successfully constructed in 2002 and has been operated for three 3 years up to now. In the 2004 campaign, siliconization as a wall conditioning was first done on the HL-2A tokamak by using glow discharge cleaning (GDC) with a gas mixture of SiH4 + He. The effects of siliconization on impurities and recycling are investigated, as well as the lifetime of siliconization, in this paper. The intensity of oxygen line is remarkably decreased after siliconization. Radiation of silicon line rapidly decreases shot by shot just after siliconization, but the effect of siliconization on the plasma properties is present all along and decreases gradually for a large amount of discharges. The effect of the siliconization can be maintained to about 180 discharges with similar discharge parameters.

Molecular cloning of novel α-gliadin genes from Crithopsis delileana and the evolution analysis with those from Triticeae

Zhi-Fu Guo,Xiang-Yu Long,Pan Dong,Yu-Ming Wei,Li-Ping Bai,Xiao-Xuan Dang,Hao-Lei Wan,Li-Jun Zhang,You-Liang Zheng 한국유전학회 2011 Genes & Genomics Vol.33 No.2

The α-gliadins from Crithopsis delileana (Schult) Roshev (2n=2x=14, KK) were investigated by Acid polyacrylamide gel electrophoresis (A-PAGE) analysis. It was indicated that the electrophoresis mobility of gliadins from C.delileana had obvious difference with those from common wheat in α, γand ω region. Using primers designed from published sequences of α-gliadin genes, three α-gliadin genes were isolated from C. delileana, which were designated as gli-ka1,gli-ka2 and gli-ka3, respectively. Two in-frame stop codons were found in the coding sequences of gli-ka3, indicating that gli-ka3 could be a pseudogene. The gli-ka2 was a gliadin with an odd number of cysteines, resulting from a non-synonymous mutation. This change might lead to the interactive behavior of gli-ka2. Three α-gliadin genes of C. delileana had the similar but not identical primary structures to the corresponding gene sequences from other wheat related species. By the alignment of α-gliadin genes from Triticeae,phylogenetic analysis indicated that three α-gliadin genes of C. delileana clustered together with all α-gliadin genes from Ee genome of Lophopyrum elongatum by an interior paralleled branch.

Evolution of Multi-temporal Landslides at Luhu, Miaoli County, Taiwan

( Che-ming Yang ),( Keng-hao Kang ),( Kuo-wei Li ),( Hui-jung Wang ),( Ching-ping Hsiao ),( Jyh-jong Liao ),( Yii-wen Pan ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

A deep-seated landslide took place in Luhu, Miao-Li, Taiwan during intermittent rainfall in April 2018; initially, there were successive rock falls and gully erosion then leaded to a deep-seated landslide failure eventually. This study aims to understand the failure mechanism and the process of deep-seated failure. The study site is a steep anaclinal slope consisting of the Miocence Shihti Formation with thick sandstone, interbedded of sandstone and shale. We collected multi-temporal ortho-images and digital elevation (surface) models from 1980 to 2019 for geological investigation, geomorphological interpretation and numerical simulation. The images reveal several slope failures at 1998, 2003, 2005, 2009, 2015, 2017 and 2018 with various volume and failure types. The study area contains three sub-regions: the north, the northwest and the southwest slopes. The slope failure occurred repeatedly inside the north and the northwest slopes in the early stage. Gully erosion in the southwest slope progressed to a landslide on April 5, 2018 first and expanded to cover the deep-seated landslide failure in the northwest slope eventually; the slope failure resulted in a natural dam. After the landslide, several open cracks appeared near to the crown. The estimated maximum thickness, area and volume of the deep-seated landslide are ~60 m, 65,000 m2 and ~2 Mm3, respectively. Based on these results, we also performed a series of numerical simulation using the software RAMMS to interpret the run out and the deposition of this landslide case.