Influences of Bridge Group on Thermal and Mechanical Properties of Epoxy Resins

Liu Yuan,Zhao Jun,Liu Ai-Qin,Liu Xiao-Qing,Luo Jun 한국고분자학회 2020 폴리머 Vol.44 No.4

In order to obtain thermosetting epoxy resin, it is the prerequisite condition that the epoxy precursor must contain at least two epoxy groups. Thus, bridge group is needed to link the epoxy groups, and naturally, the chemical structure of the bridge group may also influence the thermomechanical performances of the cured epoxy resin. However, literature about the effects of bridge group on properties of cured epoxy is seldom published. To fill the gap, three model epoxy monomers containing different bridge groups have been synthesized from 4,4"-dihydroxydiphenyl, 1,1-bis(4- hydroxyphenyl)cyclohexane and bisphenol A in this work. After chemical structure confirmation, all of the monomers are cured by methylhexahydrophthalic anhydride (HMMPA), and the properties of the obtained cured network are evaluated by differential scanning calorimetry (DSC), dynamic thermomechanical analysis (DMA), tensile test and scanning electron microscope (SEM). The results show that bulky bridge group can effectively increase the glass transition temperature, enhance the tensile strength, and enlarge elongation at break of the cured epoxy resin.

Research on data augmentation algorithm for time series based on deep learning

Shiyu Liu,Hongyan Qiao,Lianhong Yuan,Yuan Yuan,Jun Liu 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.6

Data monitoring is an important foundation of modern science. In most cases, the monitoring data is time-series data, which has high application value. The deep learning algorithm has a strong nonlinear fitting capability, which enables the recognition of time series by capturing anomalous information in time series. At present, the research of time series recognition based on deep learning is especially important for data monitoring. Deep learning algorithms require a large amount of data for training. However, abnormal sample is a small sample in time series, which means the number of abnormal time series can seriously affect the accuracy of recognition algorithm because of class imbalance. In order to increase the number of abnormal sample, a data augmentation method called GANBATS (GAN-based Bi-LSTM and Attention for Time Series) is proposed. In GANBATS, Bi-LSTM is introduced to extract the timing features and then transfer features to the generator network of GANBATS.GANBATS also modifies the discriminator network by adding an attention mechanism to achieve global attention for time series. At the end of discriminator, GANBATS is adding averagepooling layer, which merges temporal features to boost the operational efficiency. In this paper, four time series datasets and five data augmentation algorithms are used for comparison experiments. The generated data are measured by PRD(Percent Root Mean Square Difference) and DTW(Dynamic Time Warping). The experimental results show that GANBATS reduces up to 26.22 in PRD metric and 9.45 in DTW metric. In addition, this paper uses different algorithms to reconstruct the datasets and compare them by classification accuracy. The classification accuracy is improved by 6.44%-12.96% on four time series datasets.

Compressed Magnetic Field in the Magnetically Regulated Global Collapsing Clump of G9.62+0.19

Liu, Tie,Kim, Kee-Tae,Liu, Sheng-Yuan,Juvela, Mika,Zhang, Qizhou,Wu, Yuefang,Li, Pak Shing,Parsons, Harriet,Soam, Archana,Goldsmith, Paul F.,Su, Yu-Nung,Tatematsu, Ken’ichi,Qin, Sheng-Li,Garay, Guido American Astronomical Society 2018 ASTROPHYSICAL JOURNAL LETTERS - Vol.869 No.1

A Novel Self-Healing Polyurethane with High Transparency and Strength: Effects of Multiple Supermolecular Forces

Yuan Liu,Yanmei Liao,Yintao Long,Yuxiang Qian,Shengqiang Nie,Yi Wang,Jia Zeng,Chunmei Zhang,Linbo Tian,Jun Luo 한국고분자학회 2022 폴리머 Vol.46 No.3

It is a considerable challenge for expanding the applications of self-healing polyurethane because of the dilemma in balancing its mechanical and self-healing properties. Herein, a series of self-healing polyurethane systems (PUT-x) with short-range ordered rigid aromatic structures were synthesized by simply adjusting two kinds of diisocyanates, and by ingenious addition of aromatic chain extender. We hope to regulate the π-π interactions and further to manipulate the properties of obtained polyurethanes via adjusting the amount of the benzene rings in the molecular chains of the PUT-x systems. The PUT-5 with decent self-healing ability, optimal mechanical properties, acceptable thermal stability and favorable transparency was selected to incorporate liquid metal and fluorescent powder to fabricate conductive wire and anti-counterfeiting film. Significantly, the liquid metal could be recycled from the conductive wire conveniently without using strong acids or strong bases. Moreover, PUT-5 exemplarily withstood long-term soaking in normal saline, and no deformation could be identified.

C₂H <i>N</i> = 1 − 0 and N₂H⁺<i>J</i> = 1 − 0 observations of <i>Planck</i> Galactic cold clumps

Liu, X.-C.,Wu, Y.,Zhang, C.,Liu, T.,Yuan, J.,Qin, S.-L.,Ju, B.-G.,Li, L.-X. EDP Sciences 2019 Astronomy and astrophysics Vol.622 No.-

<P>A survey of C2H <I>N</I> = 1 − 0 and N2H<SUP>+</SUP><I>J</I> = 1 − 0 toward <I>Planck</I> Galactic cold clumps (PGCCs) was performed using the Purple Mountain Observatory’s 13.7 m telescope. C2H and N2H<SUP>+</SUP> were chosen to study the chemical evolutionary states of PGCCs. Among 121 observed molecular cores associated with PGCCs, 71 and 58 are detected with C2H <I>N</I> = 1 − 0 and N2H<SUP>+</SUP><I>J</I> = 1 − 0, respectively. The detected lines of most sources can be fitted with a single component with compatible <I>V</I>LSR and line widths, which confirms that these PGCC cores are very cold (with gas temperatures 9-21 K) and quiescent while still dominanted by turbulence. The ratio between the column densities of C2H and N2H<SUP>+</SUP> (<I>N</I>(C2H)/<I>N</I>(N2H<SUP>+</SUP>)) is found to be a good tracer for the evolutionary states of PGCC cores. Gas-grain chemical model can reproduce the decreasing trend of <I>N</I>(C2H)/<I>N</I>(N2H<SUP>+</SUP>) as a function of time. The cores with the lowest abundances of N2H<SUP>+</SUP> (<I>X</I>[N2H<SUP>+</SUP>] < 10<SUP>−10</SUP>) are the youngest, and have nearly constant abundances of C2H. In evolved cores with <I>X</I>[N2H<SUP>+</SUP>] ~10<SUP>−9</SUP>, abundances of C2H drop quickly as the exhaustion of carbon atoms. Although these PGCC cores are in different evolutionary states, they are all quite young (< 5 × 10<SUP>5</SUP> yr) with <I>N</I>(C2H) > <I>N</I>(N2H<SUP>+</SUP>). Mapping observations are carried out toward 20 PGCC cores. The PGCC cores in Cepheus have lower <I>N</I>(C2H)/<I>N</I>(N2H<SUP>+</SUP>) and larger line widths compared with those in Taurus. This implies that PGCC cores in Taurus are less chemically evolved than those in Cepheus.</P>

Expression of Codon Optimized β₂-Adrenergic Receptor in Sf9 Insect Cells for Multianalyte Detection of β-Agonist Residues in Pork

( Yuan Liu ),( Jian Wang ),( Yang Liu ),( Liting Yang ),( Xuran Zhu ),( Wei Wang ),( Jiaxiao Zhang ),( Dong Wei ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.9

β₂-adrenergic receptor (β₂-AR) was expressed efficiently using Bac-to-Bac Baculovirus Expression System in Sf9 cells as a bio-recognition element for multianalyte screening of β-agonist residues in pork. Sf9 cells were selected as the expression system, and codon optimization of wild-type nucleic acid sequence and time-dependent screening of expression conditions were then carried out for enhancing expression level and biological activity. Under optimum conditions of multiplicity of infection (MOI) = 5 and 48 h post transfection, the protein yield was up to 1.23 mg/ml. After purification by chromatographic techniques, the purified recombinant protein was applied to develop a direct competitive enzyme-linked receptor assay (ELRA) and the efficiency and reliability of the assay was determined. The IC50 values of clenbuterol, salbutamol, and ractopamine were 28.36, 50.70, and 59.57 μg/l, and clenbuterol showed 47.61% and 55.94% cross-reactivities with ractopamine and salbutamol, respectively. The limit of detection (LOD) was 3.2 μg/l and the relevant recoveries in pork samples were in the range of 73.0-91.2%, 69.4-84.6%, and 63.7-80.2%, respectively. The results showed that it had better performance compared with other present nonradioactive receptor-based assays, indicating that the genetically modified β₂-AR would have great application potential in detection of β-agonist residues.

Long non-coding RNA H19X promotes tumorigenesis and metastasis of colorectal cancer through regulating the miR-503-5p/KANK1 axis

Yuan Zihan,Zhao Haizhou,Zhi Qiaoming,Wang Sentai,Liu Chao,Han Ye,Xu Zhihua,Liu Fei,Liu Xingyi,Zan Xinquan,Wang Qiang,Wan Daiwei 한국유전학회 2022 Genes & Genomics Vol.44 No.12

Background: It has been well established that the long non-coding RNAs (lncRNAs) plays a critical role in tumor progression. However, the function of these transcripts and mechanisms responsible for their deregulation in colorectal cancer (CRC) remain to be investigated. Objective: To explore the potential effect and regulation mechanism of lncRNA H19X in colorectal cancer. Methods: We predicted and validated long non-coding RNA H19X from microarray data of colorectal cancer tissues. In addition, the biological behaviors of H19X and miR-503-5p on CRC were examined in vitro and in vivo, including MTT, colony formation assay, Hoechst33342 and transwell assay. The mRNA and protein levels of KN Motif and Ankyrin Repeat Domains 1 (KANK1) were analyzed by Quantitative real-time PCR (qRT-PCR), western blotting (WB) assay. Moreover, bioinformatics tools and dual-luciferase reporter assay were applied to demonstrate the relationship between KANK1 and miR-503-5p. Results: H19X was remarkably up-regulated in CRC tissues. Its expression related to tumor size (p = 0.041), lymph node metastasis (p = 0.037), distal metastasis (p = 0.028), advanced TNM stage (p = 0.034) and poor survival in CRC. H19X acted as an oncogenic lncRNA that induced CRC cell proliferation, invasion and metastasis. Through a number of functional studies, we found that H19X silencing inhibited the malignance phenotype of cancer cells through loss of miR-503-5p. Further studies demonstrated that miR-503-5p was involved in the progression of CRC by directly regulating the downstream target KANK1. Conclusion: Collectively, the findings of the present study indicate H19X/miR-503-5p/KANK1 axis has critical role in the progression of colorectal cancer, providing an effective prognostic indicator and promising target in treatment of colorectal cancer.

Coffin-Siris syndrome in two chinese patients with novel pathogenic variants of ARID1A and SMARCA4

Liu Mingjie,Wan Linlin,Wang Chunrong,Yuan Hongyu,Peng Yun,Wan Na,Tang Zhichao,Yuan Xinrong,Chen Daji,Long Zhe,Shi Yuting,Qiu Rong,Tang Beisha,Tang Beisha,Chen Zhao 한국유전학회 2022 Genes & Genomics Vol.44 No.9

Background: Coffin-Siris syndrome (CSS) is a rare congenital syndrome characterized by developmental delay, intellectual disability, microcephaly, coarse face and hypoplastic nail of the fifth digits. Heterozygous variants of different BAF complex-related genes were reported to cause CSS, including ARID1A and SMARCA4. So far, no CSS patients with ARID1A and SMARCA4 variants have been reported in China. Objective: The aim of the current study was to identify the causes of two Chinese patients with congenital growth deficiency and intellectual disability. Methods: Genomic DNA was extracted from the peripheral venous blood of patients and their family members. Genetic analysis included whole-exome and Sanger sequencing. Pathogenicity assessments of variants were performed according to the guideline of the American College of Medical Genetics and Genomics. The phenotypic characteristics of all CSS subtypes were summarized through literature review. Results: We identified two Chinese CSS patients carrying novel variants of ARID1A and SMARCA4 respectively. The cases presented most core symptoms of CSS except for the digits involvement. Additionally, we performed a review of the phenotypic characteristics in CSS, highlighting phenotypic varieties and related potential causes. Conclusions: We reported the first Chinese CSS2 and CSS4 patients with novel variants of ARID1A and SMARCA4. Our study expanded the genetic and phenotypic spectrum of CSS, providing a comprehensive overview of genotype-phenotype correlations of CSS.

Numerical Simulations of Pull-In Voltage in Wave-Bar NEMS Switches for Nonvolatile Memory Application

Yuan Liu,WenFeng Xiang,JiaQi Zhang,MingHao Hu,Kun Zhao,ShouXian Zhong 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.8

Chlorophyll Fluorescence Characteristics and Rapid Light Response Curves of Alpine Rhododendron

Yuan-Huan Liu,Fang-Li Liu,Bo Long,Xiong-Li Zhou,Xue Zhang,Yue Zhang,Wen-Li Wang,Shi-Kang Shen 한국원예학회 2019 원예과학기술지 Vol.37 No.4

The aim of this study was to determine the photosynthetic adaptability of Rhododendron species toalpine environments. The chlorophyll fluorescence parameters and rapid light response curves ofeight Rhododendron species were determined under field conditions across elevation gradients (atelevations of 2,950, 3,560, 3,660, 3,770, and 4,030 m) in the Jiaozi Mountain National NaturalReserve, Yunnan Province, southwestern China. The effect of different elevations, species, and theirinteractions significantly affected most of the chlorophyll fluorescence and rapid light response curveparameters. The variable to maximum fluorescence ratio (Fv/Fm) ranged from 0.78 to 0.81 at the fiveelevation gradients. This result indicated that the studied species were well grown and adapted to thecurrent environment. The correlation analysis indicated that the elevation was positively significantlycorrelated with the photochemical efficiency of photosystem II, electron transport rate, maximumelectron transport rate, light saturation coefficient (Ek), and chlorophyll relative content (SPAD: leafchlorophyll content index) and was negatively significantly correlated with photochemicalquenching, nonphotochemical quenching, and linear initial slope values. Although no significantrelationship was observed between the elevations and Fv/Fm, the apparent difference in Fv/Fm both atelevation gradients and elevation × species levels indicated that the Rhododendron speciesdemonstrated species-specific adaptation to the environment at different elevations. Our resultsprovided evidence that Rhododendron species exhibit variations in photosynthetic activities in analpine environment at different elevations. These differences may improve the understanding of thephysiological adaptation variations of Rhododendron species across elevation gradients in associationwith climate change in the mountains of southwestern China.