Identification of a conservative site in the African swine fever virus p54 protein and its preliminary application in a serological assay

Lingyu Xu,Chenfu Cao,Zhiyi Yang,Weixin Jia 대한수의학회 2022 Journal of Veterinary Science Vol.23 No.4

Background: ASF was first reported in Kenya in 1910 in 1921. In China, ASF spread to 31 provinces including Henan and Jiangsu within six months after it was first reported on August 3, 2018. The epidemic almost affected the whole China, causing direct economic losses of tens of billions of yuan. Cause great loss to our pig industry. As ELISA is cheap and easy to operate, OIE regards it as the preferred serological method for ASF detection. P54 protein has good antigenicity and is an ideal antigen for detection. Objective: To identify a conservative site in the African swine fever virus (ASFV) p54 protein and perform a Cloth-enzyme-linked immunosorbent assay (ELISA) for detecting the ASFV antibody in order to reduce risks posed by using the live virus in diagnostic assays. Method: We used bioinformatics methods to predict the antigen epitope of the ASFV p54 protein in combination with the antigenic index and artificially synthesized the predicted antigen epitope peptides. Using ASFV-positive serum and specific monoclonal antibodies (mAbs), we performed indirect ELISA and blocking ELISA to verify the immunological properties of the predicted epitope polypeptide. Results: The results of our prediction revealed that the possible antigen epitope regions were A23–29, A36–45, A72–94, A114–120, A124–130, and A137–150. The indirect ELISA showed that the peptides A23–29, A36–45, A72–94, A114–120, and A137–150 have good antigenicity. Moreover, the A36–45 polypeptide can react specifically with the mAb secreted by hybridoma cells, and its binding site contains a minimum number of essential amino acids in the sequence 37DIQFINPY44. Conclusions: Our study confirmed a conservative antigenic site in the ASFV p54 protein and its amino acid sequence. A competitive ELISA method for detecting ASFV antibodies was established based on recombinant p54 and matching mAb. Moreover, testing the protein sequence alignment verified that the method can theoretically detect antibodies produced by pigs affected by nearly all ASFVs worldwide.

Tight Focusing Characteristics of Circularly Polarized Bessel-Gauss Beams with Fractional-order Vortex Modulation

Lingyu Wang,Yu Miao,Mingzhu Xu,Xiumin Gao 한국광학회 2023 Current Optics and Photonics Vol.7 No.2

Radially polarized beams with the ability to generate a sub-wavelength sized spot in a longitudinal field provides significant applications in microscopic imaging, optical tweezers, lithography and so on. However, this excellent property can also be achieved based on conventional circularly polarized beams. Here, we demonstrate its ability to create a strong longitudinal field by comparing the tight focusing characteristics of fractional-order vortex modulated radial polarized and left-handed circular polarized Bessel-Gauss beams. Additionally, the possibility of generating arbitrary fractional-order vortex modulated Bessel-Gauss beams with a strong longitudinal field is demonstrated. A special modulation method of left-handed circularly polarized Bessel-Gauss beams modulated by a fractional-order vortex is adopted creatively and a series of regulation laws are obtained. Specifically, the fractional-order phase modulation parameter n can accurately control the number of optical lobes. The ratio of the pupil radius to the incident beam waist β 1 can control the radius of the optical lobes. The first-order Bessel function amplitude modulation parameter β 2 can control the number of layers of optical lobes. This work not only adds a new modulation method for optical micromanipulation and optical communication, but also enriches the research on fractional vortex beams which has very important academic significance.

Attentional Connectivity-based Prediction of Autism Using Heterogeneous rs-fMRI Data from CC200 Atlas

Yaya Liu,Lingyu Xu,Jun Li,Jie Yu,Xuan Yu 한국뇌신경과학회 2020 Experimental Neurobiology Vol.29 No.1

Autism spectrum disorder (ASD) is a developmental syndrome characterized by obvious drawbacks in sociality and communication. It has crucial significance to exactly discern the individuals with ASD and typical controls (TC). Previous imaging studies on ASD/TC identification have made remarkable progress in the exploration of objective as well as crucial biomarkers associated with ASD. However, glaring deficiency is manifested by the investigation on solely homogeneous and small datasets. Thus, we attempted to unveil some replicable and robust neural patterns of autism using a heterogeneous multi-site brain imaging dataset from ABIDE (Autism Brain Imaging Data Exchange). Experiments were carried out with an attention mechanism based on Extra-Trees algorithm, taking the study object of brain connectivity measured with the resting-state functional magnetic resonance imaging (fMRI) data of CC200 atlas. With cross-validation strategy, our proposed method resulted in a mean classification accuracy of 72.2% (sensitivity=68.6%, specificity=75.4%). It raised the precision of ASD prediction by about 2% and specificity by 3.2% in comparison with the most competitive reported effort. Connectivity analysis on the optimal model highlighted informative regions strongly involved in the social cognition as well as interaction, and manifested lower correlation between the anterior and posterior default mode network (DMN) in autistic individuals than controls. This observation is concordant with previous studies, which enables our proposed method to effectively identify the individuals with risk of ASD.

Experimental Study and Constitutive Model on Complete Stress-strain Relations of Plain Concrete in Uniaxial Cyclic Tension

Xudong Chen,Lingyu Xu,Jingwu Bu 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.5

Due to the difficulties of testing concrete in direct uniaxial tension, only limited data are available. In this paper, the cyclic tensile test on the plain concrete was carried out. Based on the experimental data, the plasticity and damage evolution can be formulated with respect to elastic strain. A constitutive model for cyclic tensile behavior of concrete is proposed. The proposed model can describe the nonlinear post-peak performance of concrete in direct tension including hysteresis loops. Finally, a statistical damage model is derived to describe the microcrack growth of concrete under monotonic and cyclic tension loading. Results demonstrated that the microcracks growth of concrete under cyclic tension loading can be formulated by the Weibull cumulative distribution function.

Mechanical Behavior and Damage Evolution for Concrete Subjected to Multiple Impact Loading

Xudong Chen,Lingyu Xu,Qiao Zhu 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.6

In order to explore the dynamic mechanical properties and damage evolution for concrete under the repeated impact loading, the large-diameter (74 mm) Split Hopkinson Pressure Bar (SHPB) was used to conduct the dynamic compression test. The damage was calculated by the Weibull statistical damage model, and the stress-strain curves of concrete were analyzed to study the repeated impact loading effects on the damage of concrete. Meanwhile, the fracture process of the concrete was simulated with the finite element software (LS-DYNA) and Johnson Holmquist Concrete (*MAT_JOHNSON_HOLMQUIST_CONCRETE) constitutive model. The results showed that the dynamic elastic modulus and the peak stress of the specimens decreased with the increased number of repeated impacts, while the peak strain increased. The damage of concrete increased with the increased strain, and the damage increased sharply after the “inflection point”. In addition, the results obtained by finite element simulation agree with the experimental results.

Influence of chlorinated disinfection by-products on transmission of antibiotic resistance genes in biofilms and water of a simulated drinking water distribution system

Minglu Zhang,Lingyue Zhang,Kaizong Lin,Yue Wang,Shaofeng Xu,Miao Bai,Hairong Jiang,Shuangling Wang,Yongjing Wang,Can Zhang 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.4

The spread of antibiotic resistance genes (ARGs) caused by biofilm growth in drinking water distribution systems (DWDSs) poses a serious threat to human health. The influence of disinfection by-products (DBPs) on the distribution of ARGs and mobile genetic elements (MGEs) in different phases (biofilms and water) of DWDSs is unclear. In this study, the characteristics of microbial indices, trihalomethanes (THMs), haloacetic acids (HAAs), ARGs and MGEs in biofilms and effluents of simulated DWDS reactors were detected during 150 d of operation. During the mature biofilm periods of 90 d or 120 d, for both biofilms and effluents, seven categories of ARGs (except tetracycline) and MGEs were at their highest and lowest relative abundance in the entire operation cycle, respectively. The influence of DBPs on ARGs and MGEs in the DWDS was different in different phases. In effluents, DBPs showed a stronger relationship with ARGs compared with MGEs. THMs and HAAs had positive correlations with various ARGs, which indicated that DBPs affected the distribution of resistance genes. In biofilms, the influence of MGEs on ARGs was stronger than that of DBPs on ARGs. Thus, DBPs might be an important contributor to the enrichment and spread of ARGs in water.

Impact of Grafting Density on the Self-Assembly and Hydrophilicity of Succinylated Collagen

Wenxin Wang,Feiyi Shu,Lingyu Pan,Shanshan Huang,Xiao Tu,Ping Li,Siman Li,Yuanyuan Li,Chengzhi Xu,Yang Sun,Juntao Zhang,Haibo Wang 한국고분자학회 2020 Macromolecular Research Vol.28 No.6

Modification of protein could give their new functionality but would affect their intrinsic property and activity. In this paper, a series of succinylated collagen (SCol(n/1)) (n≥1) were prepared by modification of collagen with succinic anhydride at different molar ratio to amino groups amount of collagen. The impact of grafting density on the intrinsic self-assembly and additional hydrophilicity of succinylated collagen was explored. The results revealed that excessive grafting density of succinylated collagen would improve their hydrophilicity but weaken their self-assembly property, although the triple helix of collagen could be reserved after succinylation. SCol(1/1) (grafting density of 17%) with self-assembly property and good hydrophilicity was chosen to compare with native collagen. Compared to native collagen, thermostability of SCol(1/1) decreased slightly, however, SCol(1/1) could form softer hydrogel, which was more favorable for the proliferation of NIH/3 T3. The present work would help us to further understand the importance of grafting density for the design of modified collagen with intrinsic self-assembly property and additional new functionality.

The Influence of Regional Intellectual Capital on Regional Economic Development-Evidence from China

Liu Chao,Li Xiao,Xu Lingyu 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.6

The aim of this paper is to examine the relationship between regional intellectual capital and economic performance in China. Using the methods of factor analysis and ridge regression, this paper makes an empirical study on the function of regional intellectual capital (RIC) on regional economic development by evaluating the RIC of 17 cities in Shandong Province in 2012. It is found that RIC and the development of regional economy are positively correlated and regional intellectual capital explains 29.9 percent of the growth of GDP. But there exists some differences in the degree of their contribution to the economic development. In the four elements of intellectual capital, the regional innovation capital and structure capital have larger contribution on regional economic development than relational capital and human capital. And there also exists some differences in the level of RIC in different areas. Based on the results of such research, it will then be possible to recommend appropriate comments and suggestions of promoting balanced development of regional economy through the development of RIC.

Study on the Tensile and Shear Behaviors of Selective Laser Melting Manufactured Ti6Al4V

Hao Zhang,Tao Gao,Chang Xu,Lingyu Zhao,Haipeng Song,Ganyun Huang 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.10

The deformation and failure of Ti6Al4V produced by Selective Laser Melting (SLM) under tensile and shear stress states have been experimentally investigated with different types of the samples. The digital image correlation (DIC) method was applied to observe the deformation, crack initiation and propagation behavior. The effects of building direction on the mechanical behavior were studied. The experimental results show that the yield strength and tensile strength of SLM manufactured Ti6Al4V along the build direction is slightly lower than the horizontal one, but the vertical samples have a higher ductility than horizontal samples. Fractographic analyses were conducted to investigate the damage mechanism and fracture mode of Ti6Al4V under different loading conditions. The defects and stress states have a significant influence on damage and failure behaviors of addictively manufactured Ti6Al4V alloy. The tensile stress tends to open up the defects in the vertically built specimen while the defects tend to be closed in the horizontally built specimen due to the building orientation. The nucleation, growth and coalescence of micro voids are the main damage mechanism of SLM fabricated Ti6Al4V alloy under tensile loading condition, and the void shearing mechanism dominates the failure of shear samples.