Comparative transcriptome analysis to identify genes involved in terpenoid biosynthesis in Agriophyllum squarrosum, a folk medicinal herb native to Asian temperature deserts

Yin Xiaoyue,Yan-Xia Liu,Qian Chaoju,Zhou Shanshan,Fang Tingzhou,Fan Xingke,Gao yuan,Chang Yuxiao,Yang Jian,Ma Xiao-Fei 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.3

Agriophyllum squarrosum is a folk Mongolian medicine with pleiotropic pharmacological and ecological economic importance endemic to Asian temperature deserts. Terpenoids play critical roles in biotic and abiotic stresses due to their antioxidative activities. Based on non-targeted metabolomic analysis, we detected eight terpenoids enriched in the above-ground tissues of A. squarrosum, however, the molecular mechanism underlying terpenoids biosynthesis in this desert medicinal plant is rarely understood. Here, a comparative transcriptome analysis of diferent tissues in A. squarrosum was conducted to identify 84 unigenes encoding key enzymes in the upstream backbone biosynthesis and 53 unigenes encoding the downstream enzymes for terpenoid diversifcation. Most of the upstream genes exhibited signifcant high expression levels in leaf, and some of which were validated by qRT-PCR. Phylogenetic analysis showed that two downstream gene families OSCs (oxidosqualene cyclases) and TPSs (mainly in terpene synthases -g subfamily) had undergone notable gene expansions in A. squarrosum comparing with the other Amaranthaceae plant species and Arabidopsis. Nevertheless, most members from these two gene families showed the tissue-specifc expression in A. squarrosum, which supported the diversifcation and tissue-specifc enrichment of terpenoids across above-ground tissues. Considering to the habitat characteristics of A. squarrosum, we proposed that the enrichment of terpenoids and the functional diversifcation of terpenoids biosynthesis enzymes were more or less involved into its adaptation to stressful environments of deserts. These results expand the available genetic information underlying terpenoid biosynthesis in A. squarrosum, and contribute to deeper researches on pharmaceutical and eco-agricultural applications in this desert medicinal plant.

Complete loss distribution model of GaN HEMTs considering the influence of parasitic parameters

Shengwei Gao,Jinrui Tian,Xiaoyu Fu,Yongxiao Li,Bo Wang,Lixia Zhao 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.1

When compared with Si-based devices, Gallium Nitride High Electron Mobility Transistors (GaN HEMTs) possess the advantages of lower junction-to-case thermal resistance, smaller on-state resistance, faster switching velocity, and higher switching frequency. These advantages make them a promising power semiconductor device. However, with the enhancement of switching frequencies, the influence of parasitic parameters on switching ringing and the losses of GaN HEMTs are increasingly severe. Thus, it is necessary to predict the loss distribution by establishing an accurate loss model of the switching process. On the premise of considering parasitic inductance, nonlinear junction capacitance, and reverse transfer characteristics, this article proposes a precise switching loss model of GaN HEMTs to predict the loss distribution in the switching process. In addition, it verifies results based on the double pulse test (DPT) circuit, which validates the accuracy of the proposed model. Ultimately, based on the above-mentioned loss model, this article discussed the influence of parasitic capacitance and inductance on the output capacitance loss (Eqoss), the reverse conduction loss (ESD), the opening V-I overlap loss (Eopen), the closing V-I overlap loss (Eclose), and the total loss (Etotal). Then, this article produces an optimizing method to enhance the conversion efficiency of GaN HEMTs in accordance with laboratory findings.

Study on the Impact of Chatbot Characteristics of Online Shopping Mall on Customer Satisfaction and Reuse Intention in China: Hedonic Motivation and Utilitarian Motivation as Moderating Variables

Qi Gao,Xiaoyu Xing 한국무역연구원 2023 무역연구 Vol.19 No.1

Purpose – The purpose of this paper is to analyze the impact of chatbot characteristics on customer satisfaction and reuse intention. Design/Methodology/Approach – The study collected data from 259 customers with experience using chatbots on online shopping malls. Statistical programs SPSS 27.0 and AMOS 26.0 were used for data analysis in this study. The empirical analysis consisted of frequency analysis, reliability analysis, confirmatory factor analysis, and hypothesis testing, in that respective order. Findings – The results showed that chatbot characteristics (empathy, intimacy, accuracy, ease of use, social presence) and the relationship between customer satisfaction had a positive effect, and customer satisfaction had a positive effect on chatbot reuse intention. In addition, hedonic motivation showed a moderating effect on the relationship between accuracy, ease of use, and customer satisfaction, and utilitarian motivation showed a moderating effect on the relationship between accuracy and customer satisfaction. Research Implications – This paper divided the characteristics of chatbots into empathy, intimacy, accuracy, ease of use, and social presence, which provides a theoretical framework for future research on chatbots, and has certain reference value. The importance of consumer psychological variables is confirmed by analyzing hedonic motivation and utilitarian motivation as moderating variables. In addition, the results of this study are of great significance to the application and improvement of chatbots utilized by online shopping mall companies. In the online shopping mall environment, retailers can use chatbots as a communication supplementary strategy to participate in customer service and improve the efficiency of the customer shopping experience.

NOVEL SEMI-SUPERVISED FAULT DIAGNOSIS METHOD COMBINING TRI-TRAINING AND DEEP BELIEF NETWORK FOR CHARGING EQUIPMENT OF ELECTRIC VEHICLE

Dexin Gao,Xihao Lin,Xiaoyu Zheng,Qing Yang 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.6

It is of great significance to make fault diagnosis for charging equipment of electric vehicle (EV) accurately and timely. The methods based on deep learning are promising because they can extract fault features and conduct fault diagnosis effectively. However, deep learning networks require a large number of labeled samples for model training, and in practical conditions, the labeled samples available of charging equipment are quite limited. To address these problems, we, inspired by semi-supervised learning, proposed a semi-supervised charging equipment fault diagnosis method combining Tri-training and deep belief network (DBN). The proposed method adopts Tri-training to enable full utilization of unlabeled data of charging equipment, and obtain a large amount of valid pseudo-labeled data, which will be used for the training of Tri-DBN model. Subsequently, the fault features of charging equipment are input into Tri-DBN, which is used for the classification and identification of charging equipment faults. The experimental results show that the proposed method effectively improves the faults classification accuracy of charging equipment and show more than 90 % accuracy at all fault types. In addition, this method still performs well in the presence of less labeled data.

A comprehensive gene network for fine tuning floral development in poplar

Zhong Chen,Xiaoyu Yang,Xiaoxing Su,Kai Gao,Pian Rao,Xinmin An 한국유전학회 2017 Genes & Genomics Vol.39 No.7

Herbaceous model species, especially Arabidopsis has provided a wealth of information about the genes involved in floral induction and development of inflorescences and flowers. While the genus Populus is an important model system for the molecular biology of woody plant. These two genuses differ in many ways. This study was designed to improve understanding of flower development in poplar at a system level, as its regulatory pathway to a large extent remains poorly known, owing to the presently limited mutant pool. To address this issue, a poplar GeneChip was employed to detect genes expressed during the whole floral developmental process. Using the expressed floral genes, a systematic gene network was constructed with the aid of functional association with Arabidopsis. The results suggested that autonomous, gibberellin, vernalization, photoperiod, ethylene, brassinosteroid, stress-induced and floral suppression pathways are involved in poplar flowering. Modularity analysis revealed several pathways in common with Arabidopsis, such as autonomous, gibberellin, vernalization and photoperiod pathways. In addition, brassinosteroid, stress-induced and floral suppression pathways were implicated as additional novel pathways. Notably, a difference in vernalization between Arabidopsis and poplar was revealed. Autonomous, gibberellin, vernalization, photoperiod, ethylene, brassinosteroid, stress-induced and floral suppression pathways integrated into a systematic gene network in floral development of poplar. Compared to Arabidopsis, brassinosteroid, stressinduced and floral suppression pathways are additional in poplar, and FLC is absent in vernalization pathway in poplar. Preliminary conclusions drawn here provide a basis for both identification of key genes and elucidation of molecular mechanisms involved in poplar floral development.

Experimental Study on Seismic Behavior of Roof Joint

Yao Cui,Xiaoyu Gao,Hongtao Liu,Satoshi Yamada 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.4

Experimental study was conducted to investigate the seismic behavior of roof joint. Eight full-scale specimens were tested considering the eff ects of axial force, joint height, hole shape of base plate and edge distance of concrete on the failure mode and resistance capacity of roof joint. With the increase of axial force, the hysteretic curves were fuller. The mechanical model of roof joint change from bending to shear. With the increase of joint height, the ultimate strength of roof joint decreased. If the hole shape of base plate changed from circle to loose, the slip behavior of roof joint appeared and the ultimate strength of roof joint decreased. The damage of edge concrete may occur if the edge distance of concrete was not big enough.

Preparation, characterization, and properties of lutein block polyethylene glycol copolymer loading with lutein nanoparticles

Peng Liu,Xiaoyu Bai,Xingtong Gao,Kai Liu,Aixiang Li,Zijian Lyu,Qiuhong Li 한국고분자학회 2023 Macromolecular Research Vol.31 No.3

In this paper, lutein block polyethylene glycol (lutein-b-PEG) copolymers were synthesized by hydrophilic modification of lutein with carboxylated polyethylene glycol (CT-PEG). The unreacted lutein was loaded into micelles formed by self-assembly of block copolymers to prepare composite nanoparticles. The results of FT-IR, 1H NMR, gel permeation chromatography (GPC), UV–vis and critical micellar concentration (CMC) showed that the double terminal carboxyl group ratio of CT-PEG reached 50.31%, and lutein-b-PEG was successfully synthesized without destroying the structure of lutein. Compared with lutein, the retention rate of lutein composite nanoparticles increased from 4.32 to 81.3% after 30 days of storage in the dark. In addition, the saturation solubility and bioaccessibility of lutein nanoparticles were increased 35 times and 5.2 times, respectively, due to micellar formation and improved water solubility. These findings indicated that the lutein composite nanoparticles modified with PEG significantly improved the chemical stability, water solubility, and bioaccessibility of lutein.

Genomic characterization and pathogenic study of two porcine reproductive and respiratory syndrome viruses with different virulence in Fujian, China

Xiukun Sui,Ting Xin,Xiaoyu Guo,Hong Jia,Ming Li,Xintao Gao,Jing Wu,Yitong Jiang,L.Willems2,Hongfei Zhu,Shaohua Hou 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.3

Two strains of porcine reproductive and respiratory syndrome virus (PRRSV) were isolated in 2006 and 2016 and designated as FZ06A and FZ16A, respectively. Inoculation experiments showed that FZ06A caused 100% morbidity and 60% mortality, while FZ16A caused 100% morbidity without death. By using genomic sequence and phylogenetic analyses, close relationships between a Chinese highly pathogenic PRRSV strain and the FZ06A and FZ16A strains were observed. Based on the achieved results, multiple genomic variations in Nsp2, a unique N-glycosylation site (N33→K33), and a K151 amino acid (AA) substitution for virulence in the GP5 of FZ16A were detected; except the 30 AA deletion in the Nsp2-coding region. Inoculation experiments were conducted and weaker virulence of FZ16A than FZ06A was observed. Based on our results, a 30 AA deletion in the Nsp2-coding region is an unreliable genomic indicator of a high virulence PRRSV strain. The Nsp2 and GP5 differences, in addition to the virulence difference between these two highly pathogenic PRRSV strains, have the potential to be used to establish a basis for further study of PRRSV virulence determinants and to provide data useful in the development of vaccines against this economically devastating disease.

Surface Modification with Pluronic P123 Enhances Transfection Efficiency of PAMAM Dendrimer

Xiang Wang,Shen Gao,Xin Wu,Wei Fan,Baoyue Ding,Xiaoyu Wang,Wei Zhang,Xueying Ding,Jing Gao,Quangang Zhu,Jiyong Liu,Zhen Cai 한국고분자학회 2012 Macromolecular Research Vol.20 No.2

To improve gene delivery efficiency and decrease cytotoxicity of polyamidoamine (PAMAM) polymers,P123-g-PAMAM was synthesized by modifying PAMAM with pluronic P123. The structure of the synthesized polymers was analyzed using proton nuclear magnetic resonance. The polymers were able to self-assemble with DNA,forming nanometer-scale complexes. Particle size measurement confirmed that the mean diameter of the polyplexes was 100-250 nm. The cytotoxicity and transfer efficiency were measured and compared with those of PEI and PAMAM. All of the polyplexes showed significantly low cytotoxicity in the MCF-7, HepG2, and 293T cell lines. In addition, the low level of P123 grafting to PAMAM showed significantly higher transfection efficiency than unmodified PAMAM at the optimal N/P ratio. These results suggest that P123-ylated PAMAM may prove as a useful carrier for gene delivery.

Preparation of Heparin-Functionalized Microspheres and Study on Their Adsorption Characteristic for Basic Protein Lysozyme

Jiying Men,Ruixin Wang,Xiaoyu Hu,Hongyu Zhao,Hongwei Wei,Cong Hu,Baojiao Gao 한국고분자학회 2016 Macromolecular Research Vol.24 No.2

In suspension polymerization system, poly(glycidyl methacrylate) (PGMA) microspheres are firstly prepared. Then, ring opening reaction takes place when heparin is bonded on PGMA microspheres to obtain functional PGMA-heparin microspheres. The chemical structure and physicochemical characters of PGMA-heparin microspheres are fully characterized with infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and zeta potential determination. The adsorption properties of PGMA-heparin for lysozyme are mainly investigated. The effects of the main factors on the adsorption properties are explored, furthermore the adsorption mechanism is analyzed in depth, and the adsorption thermodynamics is also researched. The experimental results show that the strong electrostatic interaction is formed between high density of negative charge coming from the carboxyl groups or sulfonic acid groups of heparin and the positive charge of basic protein lysozyme. The adsorption of PGMA-heparin for lysozyme is dependent on the pH value of the medium, and the saturated adsorption amount of PGMA-heparin for lysozyme possesses a maximum at pH 8, which reaches up to 654 mg/g. The adsorption of PGMA-heparin for lysozyme is an exothermic process which is driven by entropy, and the adsorption amount decreases with increasing the temperature.