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Rapid evolution of porcine reproductive and respiratory syndrome virus (PRRSV) is the bottleneck for effective prevention and control of PRRS. Thus, understanding the prevalence and genetic background of PRRSV strains in swine-producing regions is important for disease prevention and control. However, there is only limited information about the epizootiological situation of PRRS in the Xinjiang Uygur Autonomous Region, China. In this study, blood or lung tissue samples were collected from 1,411 PRRS-suspected weaned pigs from 9 pig farms in Changji, Shihezi, and Wujiaqu cities between 2020 and 2022. The samples were first tested by RT-quantitative PCR, yielding a PRRSV-2 positive rate of 53.6%. Subsequently, 36 PRRSV strains were isolated through initial adaptation in bone marrow-derived macrophages followed by propagation in grivet monkey Marc-145 cells. Furthermore, 28 PRRSV-positive samples and 20 cell-adapted viruses were selected for high-throughput sequencing (HTS) to obtain the entire PRRSV genome sequences. Phylogenetic analysis based on the nucleotide sequences of the ORF5 gene of the PRRSV strains identified in this study grouped into sub-lineages 1.8 and 8.7 the former being the dominant strain currently circulating in Xinjiang. However, the NSP2 proteins of the Xinjiang PRRSV strains shared the same deletion patterns as sub-lineage 1.8 prototype strain NADC30 with the exception of 4 strains carrying 2-3 additional amino acid deletions. Further analysis confirmed that recombination events had occurred in 27 of 37 PRRSVs obtained here with the parental strains belonging to sub-lineages 1.8 and 8.7, lineages 3 and 5, with the recombination events having occurred most frequently in the 5' and 3' termini of ORF1a and 5' terminus of ORF1b.

In recent years, education has been the focus of attention from all walks of life, and the education curriculum of colleges and universities is the key to cultivating students’ comprehensive quality and ability. College education needs to optimize the design of higher education courses to achieve the goal of talent training and to design a teaching content recommendation system based on students’ cognitive level. On the one hand, this study uses the support vector machine algorithm to quantitatively analyze students’ qualitative comments on the course to extract useful teaching feedback for course design optimization, and on the other hand, designs a teaching content recommendation system based on deep learning algorithm as an adjustment tool to jointly improve the teaching quality of higher education and improve the learning effect of students. The CBOW model and SVM algorithm model were used to analyze a large number of qualitative texts, and the cosine similarity of related words was calculated, such as “recommended” 0.98416, “sufficient” 0.9986 and “good” 0.99762, and the word heat map was drawn according to the word frequency. In addition, an empirical study was conducted on the teaching content recommendation system in school A. The accuracy of the recommendation results and the impact of the system on students’ academic performance were analyzed. The average accuracy of the learning resource recommendation results was 91.65%. The student’s scores were significantly improved after using the system, which proved that the design of the system was effective.

Cement is an important building material with high energy consumption and high emission, while energy conservation and emission reduction has been the consensus over the world in the background of the global climate warming. Aiming at the problems of large cement consumption and long construction period of deep mixing column, a double-liquid curing agent composed of low thickness cement slurry and sodium silicate solution is proposed to replace cement slurry in deep mixing columns. The installation equipment is modified to adapt to the double-liquid curing agent. The effect of the double-liquid curing agent is researched through field​ tests, which verify the environmental and economic benefits in cement saving and construction accelerating. The double-liquid curing agent for deep mixing columns has great promotion potential.

Purpose: Taichi Chuan was previously shown to benefit physical health, but the results were inconsistent. The main reason is that the mechanism is not clear and may be interpreted differently. In this systematic review, we analyzed the data obtained from various randomized controlled trials to identify the effectiveness of Taichi Chuan and the mechanism by which it improves the physical health of adults. Methods: We systematically searched various databases, including PubMed, Web of Science, Scopus, Embase, EBSCO Host, Science Direct, CNKI, Wan-Fang, and VPCS, and obtained 1448 articles for review. The articles were selected following the PICO eligibility criteria. We performed a systematic review and meta-analysis to interpret the results of the different studies. Results: We included 16 studies in the systematic review. Six of them were of very high quality, ten were of acceptable quality. Overall, the results showed that Taichi Chuan is beneficial to physical fitness, but not all indices supported this statement. Specifically, the effects were significant on Balance (ES = − 0.33; P = 0.02), BMI (ES = − 0.83; P

Abstract Background Allergic diseases are highly prevalent in the women of childbearing age. As we know, the immune system could change when pregnancy, which may affect the course of allergic diseases. Meanwhile, they also can affect the course and outcome of pregnancy. The data on incidence of allergies during pregnancy is lacking and conducting clinical trials in pregnant women was limited, therefore, we observed a prebirth cohort to supplement the relevant data and strengthen concerned research conductions. Objective We aim to obtain the incidence of allergies in urban pregnancy and explore the relevant factors of allergic diseases in urban pregnancy. Methods We design a multicenter and prospective cohort in 20 institutions above municipal level which were eligible according to the study design from 14 provinces covering all-side of China. This cohort was conducted from 13+6 weeks of gestation to 12 months postpartum and in our study, we chose the prenatal part to analyze. The outcome was developing allergies during pregnancy, which were diagnosed by clinicians according to the uniform criterion from National Health Commission. All the data was collected by electronic questionnaires through tablet computers. Results The incidence of allergic diseases in urban pregnant women was 21.0% (95%CI 20.0% ~ 22.0%). From social demography data, the history of allergies of pregnant women and their parents had statistical significance(p

Abstract Pregnant women infected with HCV should be given attention due to their special physiological stage and the effect on offspring health. To examine the prevalence of HCV infection among pregnant women in part of China and explore relevant factors during pregnancy, a cross-sectional study was conducted in four maternal and children health care institutions (MCHC) in Guangdong, Hunan and Chongqing. Pregnant women who were delivered, induced or spontaneous abortion were included and relevant information was collected through the Hospital Information System. Results showed that the prevalence of HCV among pregnant women in four MCHCs was 0.11% (95% CI 0.09–0.13%). Age, occupations, regions, syphilis-infection, intrahepatic cholestasis of pregnancy (ICP), and placenta previa were significant factors (all P

Abstract Background Brucella spp. is an important zoonotic pathogen responsible for brucellosis in humans and animals. Brucella abortus A19 strain is a widespread vaccine in China. However, it has a drawback of residual virulence in animals and humans. Methods In this study, the BALB/c mice were inoculated with either 100 μL PBS(control group, C group), 109 CFU/mL inactivated B. abortus A19 strain (I group), 105 CFU/mL (low-dose group, L group) 106 CFU/mL live B. abortus A19 strain (high-dose group, H group), or 105 CFU/mL live B. abortus A19 strain combined with 109 CFU/mL inactivated B. abortus A19 strain (LI group). Mice were challenged with B. abortus strain 2308 at 7 week post vaccination. Subsequently, the immune and protective efficacy of the vaccines were evaluated by measuring splenic bacterial burden, spleen weight, serum IgG, interferon-gamma (IFN-γ), interleukin-4 (IL-4) percentage of CD4 + and CD8 + T cells of mice via bacterial isolation, weighing, ELISA and flow cytometry, respectively. Results The splenic bacterial burden and spleen weight of the mice in group LI were mostly equivalent to the mice of group H. Moreover, Brucella-specific serum IgG, IFN-γ, IL-4, and the percentage of CD4+ and CD8+ T cells of the LI group mice were similar to those of the H group. In the subsequent challenge test, both vaccines conferred protective immunity to wild-type (WT) 2308 strain. In addition, the levels of IL-4 and IFN-γ, CD4+ and CD8+ T cells in these mice were similar to those of the mice in the H group. Conclusions Combined immunization with low dose live vaccine and inactivated vaccine allowed to reduce the live B. abortus A19 vaccine, dose with an equivalent protection of the high-dose live vaccine.

Infrared dim small target detection has received a lot of attention, because it is a crucial component of the IR search and track systems (IRST). The robust principal component analysis (RPCA) is a common detection framework, which works with poor performance with complex background edges and sparse clutters due to the inappropriate approximation of sparse items. A nonconvex constraint detection method based on the difference between the L1 and L2 (L1–L2) norm and total variation (TV) is presented. The L1–L2 norm is a more accurate sparse item approximation of L0 norm, which can achieve a better description of the sparse item to separate the target from the complex backgrounds. Then, the total variation norm is conducted on the target image to suppress the sparse clutters. The new model is solved using the alternating direction method of multipliers (ADMM) method. Then, the subproblems in the model are tackled by the difference of convex algorithm (DCA) and the Newton conjugate gradient (Newton-CG) solving L1–L2 norm and TV norm, respectively. In the experiment, we conducted experiments on multiple and single target datasets, and the proposed model outperforms the state-of-the-art (SOTA) methods in terms of background suppression and robustness to accurately detect the target. It can achieve a higher true position rate (TPR) with a low false position rate (FPR).

High field-strength elements have been regarded as one of the most important discriminations in subduction zone magma. However, the spatial distribution of Nb and Ta in subduction zone-related rocks has been rarely studied; it is still unclear whether there is a quantitative relationship between the Nb–Ta concentrations and their subduction distance. In this paper, the Nb–Ta concentrations of mafic rocks in arc tectonic systems were calculated from a statistical perspective based on the combined geophysical model and geochemical database. The results showed a typical spatial distribution pattern. The threshold value of Nb (12.20 ppm) and Ta (0.796 ppm) in arc settings was estimated by a cumulative distribution function, which can be used to determine whether the rock is generated in arc tectonic environment. A probability density function of Nb–Ta contents and related subduction distance has been obtained using kernel function estimation. The Nb–Ta concentrations are exponentially correlated with the subduction distance (

Brucellosis is an important zoonotic disease that causes great economic losses. Vaccine immunisation is the main strategy for the prevention and control of brucellosis. Although live attenuated vaccines play important roles in the prevention of this disease, they also have several limitations, such as residual virulence and difficulty in the differentiation of immunisation and infection. We developed and evaluated a new bacterial ghost vaccine of Brucella abortus A19 by a new double inactivation method. The results showed that the bacterial ghost vaccine of Brucella represents a more safe and efficient vaccine for brucellosis. We further characterised the antigenic components and signatures of the vaccine candidate A19BG. Here, we utilised a mass spectrometry-based label-free relative quantitative proteomics approach to investigate the global proteomics changes in A19BGs compared to its parental A19. The proteomic analysis identified 2014 proteins, 1116 of which were differentially expressed compared with those in A19. The common immunological proteins of OMPs (Bcsp31, Omp25, Omp10, Omp19, Omp28, and Omp2a), HSPs (DnaK, GroS, and GroL), and SodC were enriched in the proteome of A19BG. By protein micro array-based antibody profiling, significant differences were observed between A19BG and A19 immune response, and a number of signature immunogenic proteins were identified. Two of these proteins, the BMEII0032 and BMEI0892 proteins were significantly different (P < 0.01) in distinguishing between A19 and A19BG immune sera and were identified as differential diagnostic antigens for the A19BG vaccine candidate. In conclusion, using comparative proteomics and antibody profiling, protein components and signature antigens were identified for the ghost vaccine candidate A19BG, which are valuable for further developing the vaccine and its monitoring assays.

Brucella abortus is an important zoonotic pathogen that causes severe economic loss to husbandry and poses a threat to human health. The B. abortus A19 live vaccine has been extensively used to prevent bovine brucellosis in China. However, it is difficult to distinguish the serological response induced by A19 from that induced by natural infection. In this study, a novel genetically marked vaccine, A19ΔvirB12, was generated and evaluated. The results indicated that A19ΔvirB12 was able to provide effective protection against B. abortus 2308 (S2308) challenge in mice. Furthermore, the safety and protective efficacy of A19ΔvirB12 have been confirmed in natural host cattle. Additionally, the VirB12 protein allowed for serological differentiation between the S2308 challenge/natural infection and A19ΔvirB12 vaccination. However, previous studies have found that the accuracy of the serological detection based on VirB12 needs to be improved. Therefore, we attempted to identify potential supplementary antigens with differential diagnostic functions by combining label-free quantitative proteomics and protein chip technology. Twenty-six proteins identified only in S2308 were screened; among them, five proteins were considered as potential supplementary antigens. Thus, the accuracy of the differential diagnosis between A19ΔvirB12 immunization and field infection may be improved through multi-antigen detection. In addition, we explored the possible attenuation factors of Brucella vaccine strain. Nine virulence factors were downregulated in A19ΔvirB12. The downregulation pathways of A19ΔvirB12 were significantly enriched in quorum sensing, ATP-binding cassette transporter, and metabolism. Several proteins related to cell division were significantly downregulated, while some proteins involved in transcription were upregulated in S2308. In conclusion, our results contribute to the control and eradication of brucellosis and provide insights into the mechanisms underlying the attenuation of A19ΔvirB12.

Obstacle detection, as an important part of intelligent auxiliary driving, has received extensive attention. Among them, manhole cover detection plays an irreplaceable role in subsequent manhole cover location and defect detection. This paper starts from a macro perspective, and proposes a classification method of multi feature fusion. It sets trapezoidal region as the region of interest with prior knowledge, locks candidate region through the connectivity of edge, and extracts well cover position from the background through multi feature decision quickly and accurately. The method is implemented on the TMS320DM6437 platform, and the feasibility of the scheme is verified.

Cu-MoS2 self-lubricating coatings were prepared on high speed steel by electro-spark deposition (ESD) by electrode with drilled holes at the end of faces. The holes were filled with MoS2. The composition and micro morphology of the coatings were analysed. The effects of capacitance and deposition time on coating thickness were studied, and also the friction performance and wear mechanism were studied. The results show that there is nothing but MoS2 and Cu exist in the coating fabricated by this way. The micrographs show that the coating surface is uneven and many pores existing on the surface, showing typical characteristics of ESD; the surface quality is the best when it was prepared in the 3rd grade capacitance. Coating thickness firstly increases and then decreases with the increase of capacitance and deposition time. The self-lubricating coating prepared in the 3rd-grade capacitance has the lowest friction coefficient. The friction coefficients of the self-lubricating coatings prepared in the 1st and the 3rd grades stay almost constant with the increase of friction time. The friction coefficient of self-lubricating coatings prepared in the 5th grade show a clear upward trend when friction time increases. Scanning electron microscope images show shear-slip phenomenon on the wear surface.

The objectives of this study were to (1) investigate the efficiency of blended teaching online according to the Super Star Learning Pass model on Basic computer application for Shunde Technical Vocational College, (2) compare students' achievements before and after learning through blended teaching online according to the Super Star Learning Pass model on Basic computer application, and (3) examine students' satisfaction with of using blended teaching online according to the Super Star Learning Pass model on Basic computer application. The sample comprised 30 students at Shunde Technical Vocational College in China, derived through purposive sampling. The instruments used to collect the data were (1) blended teaching online according to the Super Star Learning Pass model on Basic computer application for enhancing learning achievement, a student's pretest and a posttest, and a teacher's satisfaction form. The data analysis statistics were percentage, mean, standard deviation, and the t-test for the dependent sample. The research findings revealed that applying blended teaching online according to the Super Star Learning Pass model on Basic computer applications for enhanced learning achievement was efficient by E1/E2 (81.40/81.23). The evaluation of content blended teaching online according to the Super Star Learning Pass model on Basic computer application teaching by the experts was appropriate at the excellent level ([x-bar]=4.78, SD. = 0.58). The evaluation of students' satisfaction with blended teaching online according to the Super Star Learning Pass model on Basic computer applications in China by 30 students. The overall students' satisfaction was a strongly agreeing level ([x-bar]=4.51, SD. = 0.50). When considering each item, it was found that blended teaching online according to the Super Star Learning Pass model on Basic computer application methods was strongly agreeing level ([x-bar]=4.67, SD. = 0.48) and combined teaching online according to the Super Star Learning Pass model on Basic computer application was strongly agree level ([x-bar]= 4.60, SD. = 0.50), respectively. According to Shunde Technical Vocational College, teachers' satisfaction with blended teaching online according to the Super Star Learning Pass model on Basic computer applications for enhanced learning achievement was high, with a mean of 4.51.

The Yellow River Basin is a major economic development area in China, and the high quality development of the basin still has great room for improvement. The coordinated development of energy, environment, economy and ecology is one of the keys to high quality development of the watershed. Aiming at the problem of energy, environment, economy and ecology restricting and promoting, this paper takes the nine provinces of the Yellow River as the research object, based on data from 2004 to 2017, through establishing the coupling coordination system of ecology, environment, economy and energy, using CRITIC method to study the characteristics of each subsystem of the basin in time and space. The results show that the score of energy, environment, economy and ecology is phased in time, and the level of compound coupling coordination is increasing year by year and the growth rate is obvious. The coupling coordination degree of the Yellow River basin has significant stage and regional characteristics in time and space, the coordination degree of the upper and middle reaches is higher than the coordination degree of the downstream coupling, but the difference between the three is gradually reduced with time.