留学生语伴互助对外语学习自我效能感的影响研究

류군 ( Liu¸ Jun ) 한국중국언어학회 2021 중국언어연구 Vol.- No.96

Based on the S-O-R theoretical model, this study analyzed the effect of language partnership on self-efficacy by selecting international students’ subjects. The following conclusions were drawn from descriptive statistics, relevant analyses, structural equation model verification and brokerage effect analysis of the research data: First, the cooperation in acquiring foreign language knowledge in the cooperation process of international students’ language partners has a great effect on helping them to increase their sense of learning effectiveness when learning a foreign language. Second, the cooperation of foreign language applications in the cooperation process of international language partners helps international students use the foreign language knowledge they have learned in real-life relationships, and greatly affects the effectiveness of learning foreign language learning. Third, foreign language emotional cooperation in the cooperation process of foreign language partners is relatively special, and research shows that it helps students learn foreign languages and experience emotions in studying abroad, and increases in their foreign language learning efficacy. Fourth, in the course of cooperation with foreign language partners, students learn foreign language easily through cooperation, and experience experience, language application practice, and emotion, and this synesthesia emotional experience affects the effectiveness of foreign language learning. The results of the research data show that the mutual assistance between the language partners of foreign students produces a sense of identification such as ease of foreign language learning, practical foreign language application and emotional experience. The model constructed in the final research process is verified: the mutual assistance between foreign students’ foreign language partners Self-efficacy in foreign language learning has a positive effect.

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.

5-Aza-2'-deoxycytidine Induces Hepatoma Cell Apoptosis via Enhancing Methionine Adenosyltransferase 1A Expression and Inducing S-Adenosylmethionine Production

Liu, Wei-Jun,Ren, Jian-Guo,Li, Ting,Yu, Guo-Zheng,Zhang, Jin,Li, Chang-Sheng,Liu, Zhi-Su,Liu, Quan-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2'-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza-CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.

De novo assembly of the transcriptome for Greenbug (Schizaphis graminum Rondani) and analysis on insecticide resistance-related genes

Jun-Jie LIU,Liu-Yang LU,Hui-Hui LIU,Ya-She LI,Xu SU,Bai-Zhong ZHANG,Xi-Ling CHEN 한국곤충학회 2019 Entomological Research Vol.49 No.8

The greenbug, Schizaphis graminum Rondani is a major pest species of wheat crops. In this study, a transcriptome sequencing, and the expression of the 12 genes related to insecticide resistance were conducted in S. graminum. The sequencing and subsequent bioinformatics analysis outputed 46,593 unigenes, among which 28,289 unigenes were annotated to corresponding functions by blasting with high homologous genes in database, giving annotation rate of 60.72%. To gain insight into the mechanism of insecticide resistance, the expression of the 12 genes related to insecticide resistance for S. graminum was investigated. The expression level of aminopeptidase N (AN), cytochrome P450 (CYP), acetylcholinesterase 1 (AC), catalase (CAT), cytochrome c oxidas (CCC), GABA receptor (GABA), glutathione S-transferase (GST) were highest in the apterous nymphs among different developmental stages; The expression level of AN, CBL, CYP, CA, SD, and GST were relatively more abundant in the abdomen compared to head and throax. The results could give out the key information about the relationship between the expression of these genes in different developmental stages, tissues, treatments and metabolism of insecticides. These genes that were co-up-regulated significantly in third instar nymphs of S. graminum induced by imidacloprid, were consistent with their putative involvement in insecticide resistance. This provides most comprehensive transcriptome data for S. graminum to further study and managenment.

Piezoelectric 6-dimensional accelerometer cross coupling compensation algorithm based on two-stage calibration

Jun Liu,Dengzhuo Zhang,Min Liu,Tongbao Zhu,Lan Qin,Jingcheng Liu 국제구조공학회 2023 Smart Structures and Systems, An International Jou Vol.32 No.2

In order to improve the measurement accuracy of the 6-dimensional accelerometer, the cross coupling compensation method of the accelerometer needs to be studied. In this paper, the non-linear error caused by cross coupling of piezoelectric sixdimensional accelerometer is compensated online. The cross coupling filter is obtained by analyzing the cross coupling principle of a piezoelectric six-dimensional accelerometer. Linear and non-linear fitting methods are designed. A two-level calibration hybrid compensation algorithm is proposed. An experimental prototype of a piezoelectric six-dimensional accelerometer is fabricated. Calibration and test experiments of accelerometer were carried out. The measured results show that the average nonlinearity of the proposed algorithm is 2.2628% lower than that of the least square method, the solution time is 0.019382 seconds, and the proposed algorithm can realize the real-time measurement in six dimensions while improving the measurement accuracy. The proposed algorithm combines real-time and high precision. The research results provide theoretical and technical support for the calibration method and online compensation technology of the 6-dimensional accelerometer.

Identification of QTLs associated with the anaerobic germination potential using a set of Oryza nivara introgression lines

Licheng Liu,Xiaoxiang Li,Sanxiong Liu,Jun Min,Wenqiang Liu,Xiaowu Pan,Baohua Fang,Min Hu,Zhongqi Liu,Yongchao Li,Haiqing Zhang 한국유전학회 2021 Genes & Genomics Vol.43 No.4

Background Rice (Oryza sativa L.) is an important crop and a staple food for half of the population around the world. The recent water and labor shortages are encouraging farmers to shift from traditional transplanting to direct-seeding. However, poor germination and slow elongation of the coleoptile constrains large-scale application of direct-seeding. Objective Thisstudy was aimed to investigate the genetic basis of the anaerobic germination(AG) potential using a set of Oryza nivara (O. nivara) introgressionlines (ILs). Methods Inthis study, a total of 131 ILs were developed by introducing O. nivara chromosomesegments into the elite indica rice variety 93-11 through advanced backcrossingand repeated selfng. A high-density genetic map has been previouslyconstructed with 1,070 bin-markers. The seeds of ILs were germinated and usedto measure coleoptile length under normal and anaerobic conditions. QTLsassociated with AG potential were determined in rice. Results Basedon the high-density genetic map of the IL population, two QTLs, qAGP1 and qAGP3 associated with AG tolerance were characterized and locatedon chromosomes 1 and 3, respectively. Each QTL explained 15% of the phenotypic variance.Specifcally, the O. nivara-derived chromosomesegments of the two QTLs were positively tolerance to anaerobic condition byincreasing coleoptile length. In a further analysis of public transcriptomedata, a total of 26 and 36 genes within qAGP1 and qAGP3 were transcriptionallyinduced by anaerobic stress, respectively. Conclusions Utilizationof O. nivara-derived alleles at qAGP1 and qAGP3 can potentially enhance tolerance to anaerobic stress at thegermination stage in rice, thereby accelerating breeding of rice varieties tobe more adaptative for direct-seeding.

Macrophages Promote Coal Tar Pitch Extract-induced Tumorigenesis of BEAS-2B Cells and Tumor Metastasis in Nude Mice Mediated by AP-1

Zhang, Peng,Jin, Yue-Fei,Zhang, Qiao,Wu, Yi-Ming,Wu, Wei-Dong,Yao, Wu,Wu, Yong-Jun,Li, Zhi-Tao,Zhao, Yong,Liu, Yu,Feng, Fei-Fei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

Background: We sought to evaluate the role of tumor associated macrophages (TAMs) on the promotion of coal tar pitch extract (CTPE)-induced tumorigenesis of human bronchial epithelial cells (BEAS-2B) and tumor metastasis in nude mice, and related mechanisms. Materials and Methods: BEAS-2B cells were first treated with 2.4 mg/mL CTPE for 72 hours. After removal of CTPE, the cells were continuously cultured and passaged using trypsin-EDTA. THP-1 cells were used as macrophage-like cells. BEAS-2B cells under different conditions (n=6/group) were injected into the back necks of nude mice, and alterations of tumor xenograft growth, indicative of tumorigenicity, and tumor metastasis were determined. Pathological changes (tumor nests and microvascular lesions) of HE-stained tumor tissues were also evaluated. The expression of AP-1(c-Jun) in xenografts and metastatic tumors was determined using immunohistochemistry. Results: Tumor size and weight in nude mice transplanted with the mixture of CTPE-induced passage 30 BEAS-2B and THP-1 cells (2:1) were increased compared to those from the CTPE-treated BEAS-2B cells at passage 30 alone at different observation time points. Tumor metastasis to lymph nodes and liver was only detected after transplantation of a mixture the two kinds of cells. The numbers of tumor nests and microvascular lesions, and the expression levels of AP-1 (c-Jun) in tumors from the mixture of two kinds of cells were increased apparently in contrast to those in tumor from the CTPE-treated BEAS-2B cells of passage 30 alone. In addition, there was positive correlation between AP-1 (c-Jun) expression level and the number of microvascular lesions, or between AP-1 (c-Jun) expression level and tumor metastasis in these two groups. Conclusions: TAMs not only facilitate tumorigenesis transformation of CTPE-induced BEAS-2B cells, but also promote tumor growth, angiogenesis and metastasis in nude mice in vivo, which may be mediated by AP-1.

Investigate the Effect of Potassium on Nodule Symbiosis and Uncover an HAK/KUP/KT Member, GmHAK5, Strongly Responsive to Root Nodulation in Soybean

Liu Jianjian,Liu Jinhui,Cui Miaomiao,Chen Xiao,Liu Junli,Chen Jiadong,Chen Aiqun,Xu Guohua 한국식물학회 2022 Journal of Plant Biology Vol.65 No.6

Leguminous plants form root nodule organs with soil rhizobia bacteria, which can fix atmospheric nitrogen (N2) and supply ammonia to the host plant. It is established that the symbiotic N fixation efficiency is substantially influenced by plant nutrients, such as molybdenum (Mo), phosphorus (P), copper (Cu), and zinc (Zn). Potassium (K+) is the most abundant cation in plant cells; however, little evidence regarding the potential link between K nutrition and symbiotic N fixation efficiency is available to date. Here, we showed that K+ deficiency reduced the efficiency of symbiotic nitrogen fixation, and inoculated with rhizobia strain USDA110 could improve plant K+ acquisition. Furthermore, we identified a potassium transporter gene (GmHAK5) that was highly expressed in the root steles and in the vasculature cells of nodules. The GmHAK5 protein was localized at the plasma membrane and could rescue the growth phenotype of yeast K+ uptake-defective mutant. The results obtained from this study provides new insights for the understanding of the potential role of K+ nutrition in modulating symbiotic N fixation in soybean.

Exosomes derived from regulatory T cells attenuates MPP+-induced inflammatory response and oxidative stress in BV-2 cells by inhibiting the TLR4/NF-κB signaling

Liu Jun,Zhang Junqing,Ao Yuanyuan 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.2

Background Parkinson’s disease (PD) is a common neurodegenerative disorder associated with microglia-mediated neuroinfl ammation in pathogenesis. Regulatory T cells (Treg cells) are involved in the regulation of microglia activation and neuroinfl ammation. However, it is yet to be established whether exosomes derived from Treg cells (Treg-Exos) possess protective eff ect against MPP + -induced infl ammation and oxidative stress in microglia. Objective In our study, we examined the function of Treg cells in the in vitro PD model. MTT assay was used to assess the viability of BV2 cells. ROS, MDA, and SOD activity were detected, and ELISA was performed to estimate the infl ammatory response and oxidative stress of BV-2 cells. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were applied to detect the level changes of genes involved in the TLR4/NF-κB signaling pathway. Results The results showed that Treg-Exos improved the cell viability of MPP + -treated BV2 cells. MPP + -induced increase in ROS and MDA production, as well as decrease in SOD activity in BV2 cells were attenuated by Treg-Exos. The increased levels of infl ammatory cytokines IL-β, IL-6, and TNF-α in MPP + -induced BV2 cells were also prevented by the treatment of Treg-Exos. Treg-Exos inhibited MPP + -induced activation of the TLR4/NF-κB signaling, indicated by decreased protein level of TLR4 and p-p65/p65 ratio in BV2 cells. Further, we also found that upregulation of TLR4 blocks the protective eff ect of Treg-Exos on MPP + -treated BV2 cells. Conclusions Collectively, Treg-Exos attenuated MPP + -induced oxidative stress and infl ammatory injury in BV-2 cells by inhibiting the TLR4/NF-κB signaling.

SUMMABILITY IN MUSIELAK-ORLICZ HARDY SPACES

Jun Liu,Haonan Xia Korean Mathematical Society 2023 대한수학회지 Vol.60 No.5

Let 𝜑 : ℝⁿ × [0, ∞) → [0, ∞) be a growth function and H^𝜑(ℝⁿ) the Musielak-Orlicz Hardy space defined via the non-tangential grand maximal function. A general summability method, the so-called 𝜃-summability is considered for multi-dimensional Fourier transforms in H^𝜑(ℝⁿ). Precisely, with some assumptions on 𝜃, the authors first prove that the maximal operator of the 𝜃-means is bounded from H^𝜑(ℝⁿ) to L^𝜑(ℝⁿ). As consequences, some norm and almost everywhere convergence results of the 𝜃-means, which generalizes the well-known Lebesgue's theorem, are then obtained. Finally, the corresponding conclusions of some specific summability methods, such as Bochner-Riesz, Weierstrass and Picard-Bessel summations, are also presented.