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The pandemic SARS‐CoV‐2 has been reported in 123 countries with more than 5,000 patients died from it. However, the original and intermediate hosts of the virus remain unknown. In this study, 1,914 serum samples from 35 animal species were used for detection of SARS‐CoV‐2‐specific antibodies using double‐antigen sandwich ELISA after validating its specificity and sensitivity. The results showed that no SARS‐CoV‐2‐specific antibodies were detected in above samples which excluded the possibility of 35 animal species as intermediate host for SARS‐CoV‐2. More importantly, companion animals including pet dogs (including one dog the SARS‐CoV‐2 patient kept and two dogs which had close contact with it) and cats, street dogs and cats also showed serological negative to SARS‐CoV‐2, which relieved the public concerns for the pets as SARS‐CoV‐2 carriers.

The high percentage of seropositivity of cats in Wuhan, the epicentre of the SARS-CoV-2 epidemic, could be due to the large number of infected human cases (more than 14 folds than that in other cities) (Table 1) where cats may have been more frequently exposed to SARS-CoV-2 patients or contaminated environment. As yet, SARS-CoV-2 serological prevalence of cats in other Chinese cities remains unknown. Therefore, a serological survey including more cities with numbers of SARS-CoV-2 human cases in China will be valuable for elucidating the role of cats in transmission of the viruses and relieve public concerns. In this study, 630 cat serum samples collected before November 2019 and 423 cat serum samples collected during SARS-CoV-2 outbreak (from February 2020 to April 2020) in 20 cities in China for detecting the prevalence of SARS-CoV-2 specific antibodies.

For management of massive data and centralized network, the data security research team has become a central issue. Role-based access control (RBAC) is a common practice to control access to sensitive data. This article uses Flex and C# to develop an RBAC model, which can make data management more flexible. Concentrating on data security, this article presents the layer structure and model design for standardized management of security access. This article also implements detailed approaches for data security by verifying parameters and codes, access control, preventing illegal users and using oracle parameters and stored procedures for database security technology. In addition, an empirical study was conducted to assess effectiveness and usefulness .

The grid marketing and grid dispatching systems store four grid structures: stations, lines, transformers, and households. However, because the standards and functional focus of each system data are not unified, the data becomes isolated and not unified. As a result, there are errors in the relationship between the grid files themselves and the files in a single system, and there are also errors in the consistency and relationship of the cross-system grid files, which ultimately leads to inaccurate grid topology. Data graph technology is a graph technology developed based on big data graph database technology. It can also use multiple data knowledge extraction technology and voice recognition technology to intuitively and efficiently construct a grid topology model to realize automatic identification of grid topology. In order to realize the standardized management of the grid structure, it provides powerful conditions. Based on the investigation of a large number of graph databases, this article integrates factors such as distribution, query language, consistency, availability, fault tolerance, scalability, storage backend, etc., and fully combines some of the characteristics of the graph data itself. Starting from the data map technology, the automatic identification model of the power grid marketing data map is built, and the power grid marketing data map is applied to the real marketing data of a power supply company. It can also realize the difference analysis of the cross-system grid structure and find the data. And accurately locate the cause of the data problem, which improves the efficiency of data management for abnormal network topology.

In the context of modern big data, power grid information technology is a particularly important work for power grid staff. In the process of the in-depth construction of smart power grid, the demand for the integration of monitoring data of marketing operation is also increasing, and the data exchange is developing towards the direction of complexity, which requires the continuous improvement of the real-time performance of data and the risks in performance, security and management risks generated by data integration should be reduced. It is particularly important to create a unified management tool for data interaction. Through the professional R&D team in big data technology, the marketing operation monitoring data sharing can be highlighted, to create an integrated marketing data center. At present, the construction of marketing operation monitoring information is the focus of the work, which can effectively promote the development of big data. Therefore, this paper analyzes the data architecture of the marketing operation monitoring platform under the smart grid for the reference of relevant research.

Minks are raised in many countries and have transmitted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to humans. However, the biologic properties of SARS-CoV-2 in minks are largely unknown. Here, we investigated and found that SARS-CoV-2 replicates efficiently in both the upper and lower respiratory tracts, and transmits efficiently in minks via respiratory droplets; pulmonary lesions caused by SARS-CoV-2 in minks are similar to those seen in humans with COVID-19. We further found that a spike protein-based subunit vaccine largely prevented SARS-CoV-2 replication and lung damage caused by SARS-CoV-2 infection in minks. Our study indicates that minks are a useful animal model for evaluating the efficacy of drugs or vaccines against COVID-19 and that vaccination is a potential strategy to prevent minks from transmitting SARS-CoV-2.

Access control plays an important role in restricting the access of key resources, preventing from invasion of illegal users or the damages caused by legal users’ unintended operations. However, most of approaches for extending the semantic description of RBAC failed to seamlessly integrate knowledge representation of RBAC and domain specific rules together. In this paper, we present a semantic rules based RBAC extension model for flexible data access and resource allocation. We first give the formal concept of the extension model. Then we discuss how to describe RBAC permission for the seamless integration in the OWL semantic description and the SWRL semantic rule description. At last, we generate the uniform authorization views based on SPARQL query, which include views authorized by both explicit and implicit manners.

Five canine distemper virus monoclonal antibodies were developed by immunizing BALB/c mice with a traditional vaccine strain Snyder Hill. Among these monoclonal antibodies, four antibodies recognized both field and vaccine strains of canine distemper virus without neutralizing ability. One monoclonal antibody, 1A4, against hemagglutinin protein of canine distemper virus was found to react only with vaccine strain virus but not field isolates, and showed neutralizing activity to vaccine strain virus. These monoclonal antibodies could be very useful tools in the study of the pathogenesis of canine distemper virus and the development of diagnostic reagents.

Background: Canine parvovirus (CPV) emerged in 1970s as a highly infectious disease. CPV modified live vaccines have been widely used to control the disease. It is urgent to develop specific monoclonal antibodies to differentiate field virus from vaccine virus in vaccinated dogs.

A canine parainfluenza virus type 5 strain was isolated from a lung sample from a diseased dog. The genome sequene of this isolate, named HeN0718, was determined and compared tho those of other previously reported canine parainfluenza viruses. Unlike previously reported viruses, the HeN0718 strain contained several nucleotide mutations in the SH gene that led to a frame shift in the open reading frame. Phylogenetic analysis based on the complete virus genome and the P, F, and HN genes showed that HeN0718 was genetically closest to D277, a Korean strain that was isolated in 2008.

Supplemental material, DS1_JVDI_10.1177_1040638719841096 for Multiplex detection of six swine viruses on an integrated centrifugal disk using loop-mediated isothermal amplification by Xiangfen Yuan, Jizhou Lv, Xiangmei Lin, Chunyan Zhang, Junhua Deng, Caixia Wang, Xiaopan Fan, Yonggui Wang, Hui Xu and Shaoqiang Wu in Journal of Veterinary Diagnostic Investigation

Under the current network economy and e-commerce environment, the market competition is increasingly fierce, and the customer demand is increasingly diversified. The traditional enterprise project management system digital business center is difficult to achieve efficient enterprise project management. Therefore, this paper proposes the digital business center design of enterprise project management system based on information technology. The data processing structure of project management business center is designed, and the overall framework of enterprise level project management system is constructed. The enterprise digital management mode and decision-making steps are optimized through the division of enterprise level project information management level, and the enterprise level project management business category level is classified. Finally, the design of enterprise level project management system digital business center is realized. Experimental results show that the proposed method can solve the problem of information transmission between enterprises, and make corresponding linkage adjustment quickly according to the changes of market environment, ensure the smooth, flexible and rapid response of enterprise supply chain, and can timely and quickly find and meet customer needs, and achieve efficient project management.

The construction time of the distribution network is long and the lines are complex. It is an important component of the power supply enterprise’s business of reducing losses and increasing efficiency. Through the data u mining processing method, based on the big data of the power grid, the use of computer automatic calculation, manual verification and other methods not only realizes accurate positioning of the crux, but also greatly saves analysis and processing time; and solves the line loss problem while completing the redundant and disordered files. The clean-up and repair of power stations and the standardized transformation of the stations with large technical line losses have reduced the power losses in the stations, improved the economic benefits of the power supply bureau and achieved remarkable results. The comprehensive management of the line loss in the station area requires the full cooperation of all relevant departments to effectively control and reduce the line loss rate, which can improve the utilization rate of electric energy, analyze the abnormal phenomenon of the line loss in the station area and further standardize the line loss management measures of the enterprise, so that the company Responding to various special situations becomes stronger.

This paper develops a CAN communication multi-way valve measurement and control system. This paper elaborates on the introduction of hydraulic circuit, the construction of measurement and control system. In the LabVIEW platform, the author designs the application program through the CAN communication card, writes the signal generator to control the multi-way valve, and then draws the flow characteristic curves of the multi-way valve.

Porcine cirvovirus type 3 (PCV3) is a newly emerging swine virus with worldwide distribution. The pathogenesis of PCV3 remains unknown due to failures in propagating and isolating the virus on successive cell lines. The virus cap protein is the only structural protein of PCV3 and no monoclonal antibodies against it are available. Although antisera are available from PCV3-infected pigs, they are not suitable for immunoassays such as immunohistochemical staining of infected tissues due to high non-specific background. Developing monoclonal antibodies against the cap protein is indispensable for elucidating PCV3 biological properties. In this study, a monoclonal antibody (mAb 1H1) with a titer of 1/25,600 that recognized the PCV3 cap protein was developed. Western-blot results showed that mAb 1H1 reacted strongly with the recombinant PCV3 cap protein preparation but not with the PCV2 cap protein. MAb 1H1 was also applied successfully for the detection of the cap protein in PCV3-infected pig tissues using immunochemistry staining. In conclusion, mAb 1H1 has significant potential uses in PCV3 diagnosis as well as the study of PCV3 biology.

Pseudorabies virus (PRV) belongs to the Herpesviridae family, and is an important veterinary pathogen. Highly pathogenic PRV variants have caused severe epidemics in China since 2011, causing huge economic losses. To tackle the epidemics, we identified a panel of mouse monoclonal antibodies (mAbs) against PRV glycoprotein B (gB) that effectively block PRV infection. Among these 15 mAbs, fourteen of them block PRV entry in a complement-dependent manner. The remaining one, 1H1 mAb, however can directly neutralize the virus independent of complement and displays broad-spectrum neutralizing activities. We further determined the crystal structure of PRV gB and mapped the epitopes of these antibodies on the structure. Interestingly, all the complement-dependent neutralizing antibodies bind gB at the crown region (domain IV). In contrast, the epitope of 1H1 mAb is located at the bottom of domain I, which includes the fusion loops, indicating 1H1 mAb might neutralize the virus by interfering with the membrane fusion process. Our studies demonstrate that gB contains multiple B-cell epitopes in its crown and base regions and that antibodies targeting different epitopes block virus infection through different mechanisms. These findings would provide important clues for antiviral drug design and vaccine development., Author summary Pseudorabies virus (PRV) is an emerging veterinary pathogen that infects many domestic animals. Since 2011, highly pathogenic PRV variants have emerged in many farms in China and posed great economic burdens to the animal industry. However, the current marketed vaccines cannot provide effective protection against these emerging strains. The envelope glycoprotein B (gB) is a major viral antigen known to play a crucial role in PRV entry. In order to control PRV epidemics and treat associated diseases, we combined structural and immunological approaches to generate potential neutralizing antibodies targeting PRV gB and investigate their working mechanisms. A total of 15 monoclonal antibodies (mAbs) were identified with good neutralizing activity. Among them, fourteen mAbs target the domain IV of PRV gB and block virus entry though complement effect. In contrast, the remaining 1H1 mAb recognizes domain I of PRV gB, which can neutralize virus entry independent of complement and probably by interfering with the membrane fusion process. Our work reveals the structural details and immunogenic properties of PRV gB and may offer important guidance for developing antiviral therapeutics and vaccines against PRV infections.

We introduce and investigate the concept of conformable fractional Nabla-Hukuhara derivative of fuzzy-valued functions on time scales. By using the theory of time scales, we show some basic properties of conformable fractional Nabla-Hukuhara derivative. Our results extend and improve the related ones in [5,7,13].

Porcine circovirus type 3 (PCV3) was initially reported in 2016 in the United States of America. Since then, the virus has been detected on swine farms in Poland, South Korea, and China using PCR. However, a serological survey of PCV3 in pig populations has never been conducted. In this study, for the first time, we established an indirect enzyme-linked immunosorbent (ELISA) assay and performed a national retrospective serological survey for PCV3. Our results showed that the PCV3-postive rate increased from 22.35% to 51.88% between 2015 and 2017. The above results suggest PCV3 has spread widely in China with increased positive rates since 2015.

Postweaning multisystemic wasting disease (PMWS) in piglets caused by porcine circovirus type 2 (PCV2) is one of the major threats to most pig farms worldwide. Among all the PCV types, PCV2 is the dominant genotype causing PMWS and associated diseases. Considerable efforts were made to study the virus-like-particle (VLP) assembly and the specific PCV2-associated epitope(s) in order to establish the solid foundation for engineered PCV2 vaccine development. Although the N-terminal fragment including Nuclear Localization Signal (NLS) sequence seems important for recombinant PCV2 capsid protein expression and VLP assembly, the detailed structural and functional information regarding this important fragment are largely unknown. In this study, we report crystal structure of PCV2 VLP assembled from N-terminal NLS truncated PCV2 capsid protein at 2.8 Å resolution and cryo-EM structure of PCV2 VLP assembled from full-length PCV2 capsid protein at 4.1Å resolution. Our in vitro PCV2 VLP assembly results show that NLS-truncated PCV2 capsid protein only forms instable VLPs which were easily disassembled in solution, whereas full-length PCV2 capsid protein forms stable VLPs due to interaction between 15PRSHLGQILRRRP27 (α-helix) and 33RHRYRWRRKN42 (NLS-B) in a repeated manner. In addition, our results also showed that N-terminal truncation of PCV2 capsid protein up to 27 residues still forms PCV2 particles in solution with similar size and immunogenicity, while N-terminal truncation of PCV2 capsid protein with more than 30 residues is not able to form stable PCV2 particles in solution, demonstrating the importance of interaction between the α-helix at N-terminal and NLS-B in PCV2 VLP formation. Moreover, we also report the cryo-EM structure of PCV2 VLP in complex with 3H11-Fab, a PCV2 type-specific neutralizing antibody, at 15 Å resolution. MAb-3H11 specifically recognizes one exposed epitope located on the VLP surface EF-loop (residues 128–143), which is further confirmed by PCV1-PCV2 epitope swapping assay. Hence, our results have revealed the structural roles of N-terminal fragment of PCV2 capsid protein in PCV2 particle assembly and pinpointed one PCV2 type-specific neutralizing epitope for the first time, which could provide clear clue for next generation PCV2 vaccine and diagnostic kits development., Author summary Porcine circovirus type 2 (PCV2) is considered as one of the most wide-spread pathogens threatening swine production by causing postweaning multisystemic wasting disease (PMWS) in piglets worldwide. Several VLP-based PCV2 vaccines are commercially available which significantly reduce the viral burden and virally induced lesions. However, prophylactic efficacy of VLP-based PCV2 vaccine largely relies on the correct VLP assembly from the individual PCV2 capsid protein. Notably, limited structural information of PCV2 N-terminal fragment containing arginine-rich patches significantly delays our understanding of PCV2 assembly at the molecular level, and the lack of solid evidence in identification of PCV2 type-specific epitope delays the development of PCV2 type-specific diagnosis kits. In this study, through the combination of structural and immunological approaches, we are able, for the first time, to disclose the structural details of the N-terminal Nuclear Localization Signal (NLS) region of PCV2 capsid protein. We show that the interaction between the α-helix from one capsid protein and the NLS-B from an adjacent capsid protein within the pentamer stabilizes the assembled PCV2 VLP in solution. Moreover, by the combination of structural determination and biochemical mapping, we have identified that a short linear sequence (134KATALT139) located within PCV2 EF-loop is a unique PCV2 type-specific neutralizing epitope. Therefore, our work has revealed the detailed structural information of PCV2 particle assembly and a PCV2 type-specific neutralizing epitope, which should provide insightful information for virus-host interaction studies and next-generation PCV2 vaccine and type-specific diagnostic kits development.

Background Porcine cirovirus type 1 (PCV1) and type 2 (PCV2) are circulating in Chinese pig herds and the infected pigs develop antibodies to both viruses. Current commercial available ELISA kits cannot differentiate PCV2-specific antibodies from the mixtures of PCV1 and PCV2 antibodies in PCV1/2-infected or PCV2-vaccinated pigs. Therefore, the need for developing PCV2-specific ELISA methods is urgent to evaluate PCV2 antibody level in exclusion of PCV1 antibody interference after PCV2 vaccination. Results Virus-like particles (VLPs) of PCV2 based on the recombinant Cap protein were expressed in Escherichia coli. A competing ELISA was established by using the VLPs as coating antigen and a PCV2-specific monoclonal antibody as the competing antibody. The competing ELISA was compared with the results obtained by using an immunoperoxidase monolayer assay on 160 serum samples. The sensitivity and specificity of this competing ELISA were determined as 96.5 and 96.0 %, at 2 standard deviation from the mean or 91.8 and 100 % at 3 standard deviations from the mean. Next, a serological survey of 1297 vaccinated serum samples collected from commercial pig herds in Beijing, Hunan and Henan provinces in China was conducted. The results showed that 85.9 % of sera having positive PCV2 antibodies. Conclusions The competing ELISA we developed in this study was both sensitive and specific to PCV2 and was suitable for large-scale PCV2 antibody monitoring in exclusion of PCV1 antibody interference after PCV2 vaccination.

Female BALB/c mice were immunized with a commercial PCV2 vaccine, and a monoclonal antibody (MAb) designated as 3H11 was achieved by hybridoma techniques. The MAb specifically reacted with Cap protein of PCV2, which has been identified by western blot. Immunoperoxidase monolayer assay results showed that 3H11 did not cross-react with PCV1-infected cells. Therefore, this work suggested that 3H11 could be a useful tool as a specific diagnostic reagent for PCV2 research.

In a previous study, we performed serial brain-to-brain passages of swine Japanese encephalitis virus in mice and sequenced the complete genomes of the F5 and F20 passaged mouse-adapted variants. In the current study, we analyzed the differences between their genome sequences and found 12 amino acid substitutions in the nonstructural proteins. We also assessed the growth characteristics of these two variants in mammalian cells in vitro and in vivo. Our investigations revealed that the F20 variant had enhanced growth characteristics and modified virulence compared with the F5 variant. We therefore conclude that multiple amino acid substitutions in the nonstructural proteins of swine Japanese encephalitis virus alter its virulence in mice.

An improved PSO is proposed to tune Energy Storage System (ESS) PI controllers' parameters. The performance of ESS active and reactive power PI controllers is very important in applying ESS to improve power systems stability in smart grid in which the ESS is required to adjust its active and reactive power quickly. Therefore, an improved PSO algorithm with the idea of the simulated annealing algorithm is applied to optimize the ESS active and reactive power PI controllers' parameters. On the basis of PSO with chaotic initialization, iteration by adding chaos disturbance and adaptive inertia weight factor, the algorithm becomes more efficient because of both location limits and step out locally optimal solution by adding the idea of the simulated annealing. The non linear simulation results test and verify the effectiveness of optimization by a 4-machine power system installed an ESS with optimization PI controllers.

A project with the goal to minimize the blast damage to the remaining pit walls has been carried out at the Aitik open pit mine in North Sweden. Factors like confinement during the blast, blast direction and size of blast holes in the contour were systematically changed. During the blasts VOD in the blast holes plus PPV and gas pressure in gauge holes behind the contour were monitored. The VOD measurements were used to check the explosive performance, to obtain the real initiation sequence and to identify the sources of the PPV pulses in the composite acceleration records. The PPV levels were used to establish a scaling law for the test area which later was used for blast damage assessments. The gas pressure measurements show that the ordinary rounds don't force any significant amounts of high pressure blast fumes into the walls, probably because the unstemmed blast holes allow venting of the fumes. In all gauge holes behind ordinary rounds, only subatmospheric pressures were recorded. This is pr...

The dead-pressing phenomenon or pressure desensitization in ANFO as well as in other civil explosives is well-known. However, to our knowledge, the detailed study of this phenomenon in ANFO has not been carried out or reported. Therefore, such a study was planned in a SveDeFo research program. Blasting experiments in iron pipes were performed. Mainly, the density of dead-pressing and the transmission distance of detonation in the dead-pressed ANFO were studied. The results show that the dead-pressing density of the tested ANFO, Prillit A (a trademark of Nitro Nobel AB in Sweden), in diameters 45 mm, 60 mm and 75 mm of steel pipes is respectively 1.35, 1.39 and 1.43 [g/cm3]. The dependence of the detonation transmission distance on the density of the ANFO has also been outlined.

Background Actinobacillus pleuropneumoniae is the causative agent of porcine contagious pleuropneumonia, a highly contagious respiratory infection in pigs, and all the 15 serotypes are able to cause disease. Current vaccines including subunit vaccines could not provide satisfactory protection against A. pleuropneumoniae. In this study, the immunoproteomic approach was applied to the analysis of extracellular and outer membrane proteins of A. pleuropneumoniae JL03 serotype 3 for the identification of novel immunogenic proteins for A. pleuropneumoniae. Results A total of 30 immunogenic proteins were identified from outer membrane and extracellular proteins of JL03 serotype 3, of which 6 were known antigens and 24 were novel immunogenic proteins for A. pleuropneumoniae. Conclusion These data provide information about novel immunogenic proteins for A. pleuropneumoniae serotype 3, and are expected to aid in development of novel vaccines against A. pleuropneumoniae.

A framework for the tool, MUIP (Management of User Interface Patterns), has been developed based on the relevant literature and a survey of existing pattern tools. The framework supports the following features: pattern authoring, manipulating forces, browsing patterns, searching patterns, versioning and customising patterns, relating patterns, manipulating collections and importing or exporting patterns. Patterns are described using the standard pattern form (PLML). An enhanced version of PLML, called PLML vl.2, has been developed so that pattern contents can be organised more effectively. Guided by this framework, a specification of a comprehensive pattern management system for manipulating dissimilar pattern collections was developed and a prototype implemented accordingly. A formal evaluation confirmed the usefulness of the prototype.

A large number of user interface (UI) pattern collections have been developed by different researchers. This paper discusses the main requirements for a tool to be used by researchers and user interface designers that can manage a repository of possibly disparate pattern collections. An analysis of the main requirements and specifications for such a tool has been carried out. Pattern tools have been surveyed to identify the functionality they provide. A framework for a UI pattern management tool has been developed in the light of the analysis and the survey.