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Infectious bursal disease (IBD) is an acute, highly contagious, immunosuppressive, and fatal infectious disease of young chickens caused by infectious bursal disease virus (IBDV). Since 2017, a new trend has been discovered in the IBDV epidemic, with very virulent IBDV (vvIBDV) and novel variant IBDV (nVarIBDV) becoming the two current dominant strains in East Asia including China. In this study, we compared the biological characteristics of the vvIBDV (HLJ0504 strain), nVarIBDV (SHG19 strain), and attenuated IBDV (attIBDV, Gt strain) using specific-pathogen-free (SPF) chicken infection model. The results showed that vvIBDV distributed in multiple tissues, replicated the fastest in lymphoid organs such as bursa of Fabricius, induced significant viremia and virus excretion, and is the most pathogenic virus with a mortality of more than 80%. The nVarIBDV had a weaker replication capability and did not kill the chickens but caused severe damage to the central immune organ bursa of Fabricius and B lymphocytes and induced significant viremia and virus excretion. The attIBDV strain was found not to be pathogenic. Further studies preliminarily suggested that the expression level of inflammatory factors triggered by HLJ0504 was the highest, followed by the SHG19 group. This study is the first to systematically compare the pathogenic characteristics of three IBDVs closely related to poultry industry from the perspectives of clinical signs, micro-pathology, virus replication, and distribution. It is of great importance to obtain an extensive knowledge of epidemiology, pathogenicity, and comprehensive prevention, and control of various IBDV strains. [ABSTRACT FROM AUTHOR]

Functionalizing macrocycle with gas capture and catalytic ability onto covalent organic frameworks (COFs) can generate hierarchical porous materials with enhanced properties, while the challenge is how to improve full utilization of the active sites and maintain the crystallinity of the parent framework. Herein, we developed a "Macrocycle-on-COF" strategy by partial in-situ linker exchange to gain core-shell hybrids containing hierarchical pores. We demonstrated that the macrocycle-on-COF with functionalized pillar[5]arene have a profound effect on highly CO 2 adsorption and abundant active sites. The photoelectrical measurement showed that the macrocycle-on-COF was an excellent photocatalyst with fast photoresponse and superior charge separation efficiency. With the assistance of light, the functionalized OH-P[5]-on-COF achieves efficient photocatalytic CO 2 cycloaddition reaction under ambient conditions (20 °C and 1 atm), in which a 99% conversion can be achieved within 3 h and the performance is superior compared to previously reported COFs. This study presents the first example of using COFs as photocatalysts for photocatalytic CO 2 cycloaddition reaction under ambient conditions. [Display omitted] • A "Macrocycle-on-COF" strategy was developed by in-situ linker exchange to gain core-shell hybrids of P[5]-on-COF. • The functionalized OH-P[5]-on-COF achieves efficient photocatalytic CO2 cycloaddition reaction under ambient conditions. • TThe first example of using COFs as photocatalysts for photocatalytic CO2 cycloaddition reaction. • The multiple intermolecular hydrogen bonds between epoxides and hydroxylated pillararene have been proved. [ABSTRACT FROM AUTHOR]

Chicken anemia virus (CAV) infection has been reported in various poultry industries worldwide. Since CAV infection is becoming increasingly prevalent, especially in local chickens of China, rapid CAV detection has become essential. The conventional diagnostic methods are time consuming and need special expertise. Therefore, in this study, we developed a specific and sensitive loop-mediated isothermal amplification (LAMP) assay for CAV detection by using multiple sequence alignment of VP2. This assay was performed at 61°C for 1 h, and there was no non-specific reaction to common avian disease viruses. The detection limit was 65 copies of viral DNA; thus, this assay showed similar sensitivity to quantitative polymerase chain reaction (qPCR) but it was more sensitive than conventional PCR. Moreover, this assay was performed using clinical samples. The LAMP assay results were 83.6% correlated to the PCR results of the clinical samples, indicating that this method is an effective tool for the rapid detection of CAV. [ABSTRACT FROM AUTHOR]

Connected vehicular cloud computing (CVCC) and the VANET can realize real-time monitoring and intelligent adjustment of traffic conditions. With the data collected by vehicles and the guidance provided by cloud computing platforms, the current traffic is facing new opportunities. CVCC is a mobile computing model, which extends the fixed nodes of traditional cloud infrastructure into mobile nodes composed of vehicles. Thus, compared to the traditional cloud infrastructures, CVCC requires a more complex mechanism to ensure the secure and efficient information transmission in both cloud platform-to-vehicle communication and vehicle-to-vehicle communication. Channel capacity, as the key parameter to measure the channel utilization, plays an important role in ensuring the reliability of CVCC service and the integrity of transmission data. In recent decades, the existing calculation methods could not solve the channel capacities problem in multi-participant VANETs. Different from the traditional calculation methods, we propose a novel calculation method in this article, which combines the core concepts of game theory and information theory, to calculate the channel capacities of multiple vehicular networks. The proposed method refreshes the concept of communication, which has potential applications in different services of CVCC. [ABSTRACT FROM AUTHOR]

To probe the epidemiology of duck circovirus (DuCV) in migrating wild ducks in China, 189 samples collected from 11 species of wild ducks from 2013 to 2016 were analyzed by PCR. Four positive samples were obtained from Mallard (2), Green-winged Teal (1), and Falcated Duck (1), and the positive rate was 2.12%. The homologous alignment of the complete genome shows that the homology of the wild duck strains is 81.6 to 95.1% to each other and 81.4 to 100% to the 32 strains from other origins. Amino acids alignment revealed that the mutable ORF2 gene has six major variable regions and many random mutation points. Phylogenetic analysis showed that the four sequences belong to two genotypes: wd2013017, wd2013046 and AY228555 (representative strain of genotype 1) belong to genotype 1, while wd2014012, wd2015028 and AY394721 (representative strain of genotype 2) belong to genotype 2. The results indicate that both genotypes of DuCV are distributed and common in migrating wild ducks. Further analysis shows that duck circovirus infection is mainly concentrated in the eastern coastal cities of China, which are part of the East Asian-Australian flyway. This suggests that wild ducks with circovirus may be an important factor in the epidemic and spread of DuCV. [ABSTRACT FROM AUTHOR]

Security confrontation is the second cornerstone of the General Theory of Security. And it can be divided into two categories: blind confrontation and nonblind confrontation between attackers and defenders. In this paper, we study the nonblind confrontation by some well-known games. We show the probability of winning and losing between the attackers and defenders from the perspective of channel capacity. We establish channel models and find that the attacker or the defender wining one time is equivalent to one bit transmitted successfully in the channel. This paper also gives unified solutions for all the nonblind confrontations. [ABSTRACT FROM AUTHOR]

This paper first presents a new generally perturbed compressed sensing (CS) model y=(A+E)(x+u)+e, which incorporated a general nonzero perturbation E into sensing matrix A and a noise u into signal x simultaneously based on the standard CS model y=Ax+e and is called noise folding in completely perturbed CS model. Our construction mainly will whiten the new proposed CS model and explore in restricted isometry property (RIP) and coherence of the new CS model under some conditions. Finally, we use OMP to give a numerical simulation which shows that our model is feasible although the recovered value of signal is not exact compared with original signal because of measurement noise e, signal noise u, and perturbation E involved. [ABSTRACT FROM AUTHOR]

Infectious bursal disease is an acute, immunosuppressive infectious disease in chickens caused by the infectious bursal disease virus (IBDV), which causes huge economic losses to the global poultry industry. Persistently circulating very virulent IBDV (vvIBDV) and newly emerging novel variant IBDV (nVarIBDV) are the two dominant epidemic strains of IBDV in East Asian countries such as China. Compared to lethal vvIBDV, nonlethal nVarIBDV has more insidious pathogenicity and can partially escape the immune protection of the existing vvIBDV vaccine, suggesting its potential adaptive survival strategy. However, the underlying molecular mechanism remains unknown. The viral capsid protein VP2 is closely related to cell tropism, virulence, and antigenic variation of IBDV. In this study, for the first time, we demonstrated that residue 279 of VP2 is responsible for the difference in pathogenicity between nVarIBDV and vvIBDV and that the D279N substitution reduces the lethality of vvIBDV from 70% to 0%. Moreover, a significant reduction in the viral load and inflammatory factor levels in the immune organs and blood of infected chickens may be important mechanisms for reducing the lethality of IBDV. Additionally, residue 279 was an important molecular basis for the antigenic differences between nVarIBDV and vvIBDV. D279N substitution reduced the neutralizing ability of vvIBDV antiserum against nVarIBDV by affecting the binding ability of antibodies and antigens. Our results indicate that nVarIBDV has an infection transmission strategy that facilitates its survival by hiding viral pathogenicity and escaping antiserum neutralization, which not only has significant implications for the systemic cognition of viral genetic evolution and pathogenesis but also provides new ideas for the comprehensive prevention and control of IBDV. [ABSTRACT FROM AUTHOR]

Residual Network (ResNet) is a distinguished network structure in deep learning, and its layers can be profound. We theoretically explore the mathematics characteristics of the ResNet, in particular, to pay attention to the gradient information, which is a powerful and straightforward mathematical tool for analysing the properties of ResNet, such as the gradients of the loss function with respect to the input and the weight parameters and the gradient of the entry of the logits with respect to the input. A theorem about the explicit matrix expression of gradients in Resnet is given in this work. A rigorous mathematical and logical derivation of the theorem is obtained in detail by the matrix derivative definition and matrix differentiation. We further provide explicit matrix expressions of some deep learning algorithms in ResNet, including backpropagation, gradient-based adversarial attacks, and gradient-based saliency maps. Furthermore, the reasons why the ResNet network works are analysed. Finally, experimental results are provided to verify the correctness and efficiency of the proposed theorem. [ABSTRACT FROM AUTHOR]

Urea electrolysis is regarded as a prospective method for energy-saving hydrogen production. However, the practical application of this technology is limited by the lack of high-performance bifunctional catalysts for hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). Herein, a heterostructure catalyst composed of NiFe layered double hydroxide (LDH) and sulfides (NiFe LDH-NiFeSx/NF) catalysts is prepared via a simple one-step hydrothermal approach. Remarkably, the prepared NiFe LDH-NiFeSx/NF required 138 mV and 1.34 V to achieve 10 mA cm−2 for HER and UOR in 1 M KOH and 0.33 M urea, respectively. Furthermore, when NiFe LDH-NiFeSx/NF is used as a cathode for urea electrolysis, only 1.44 V is required at 10 mA cm−2, which is much lower than the 1.53 V needed for overall water splitting. [ABSTRACT FROM AUTHOR]

A novel approach for the parameter identification of coupled map lattice (CML) based on compressed sensing is presented in this paper. We establish a meaningful connection between these two seemingly unrelated study topics and identify the weighted parameters using the relevant recovery algorithms in compressed sensing. Specifically, we first transform the parameter identification problem of CML into the sparse recovery problem of underdetermined linear system. In fact, compressed sensing provides a feasible method to solve underdetermined linear system if the sensing matrix satisfies some suitable conditions, such as restricted isometry property (RIP) and mutual coherence. Then we give a low bound on the mutual coherence of the coefficient matrix generated by the observed values of CML and also prove that it satisfies the RIP from a theoretical point of view. If the weighted vector of each element is sparse in the CML system, our proposed approach can recover all the weighted parameters using only about M samplings, which is far less than the number of the lattice elements N. Another important and significant advantage is that if the observed data are contaminated with some types of noises, our approach is still effective. In the simulations, we mainly show the effects of coupling parameter and noise on the recovery rate. [ABSTRACT FROM AUTHOR]

Infectious bursa disease (IBD) is an acute, highly contactable, lethal, immunosuppressive infectious disease caused by the Infectious bursa disease virus (IBDV). Currently, the emerged novel variant IBDV (nVarIBDV) and the sustainedly prevalent very virulent IBDV (vvIBDV) are the two most prevalent strains of IBDV in China. The antigenic properties of the two prevalent strains differed significantly, which led to the escape of nVarIBDV from the immune protection provided by the existing vvIBDV vaccine. However, the molecular basis of the nVarIBDV immune escape remains unclear. In this study, we demonstrated, for the first time, that residues 252, 254, and 256 in the P DE of VP2 are involved in the immune escape of the emerging nVarIBDV. Firstly, the IFA-mediated antigen-antibody affinity assay showed that P BC and P DE of VP2 could affect the affinity of vvIBDV antiserum to VP2, of which P DE was more significant. The key amino acids of P DE influencing the antigen-antibody affinity were also identified, with G254N being the most significant, followed by V252I and I256V. Then the mutated virus with point or combined mutations was rescued by reverse genetics. it was further demonstrated that mutations of V252I, G254N, and I256V in P DE could individually or collaboratively reduce antigen–antibody affinity and interfere with antiserum neutralization, with G254N being the most significant. This study revealed the reasons for the widespread prevalence of nVarIBDV in immunized chicken flocks and provided innovative ideas for designing novel vaccines that match the antigen of the epidemic strain. • P DE and P BC of IBDV VP2 affect the antiserum-VP2 affinity, with P DE being more significant. • Residues 252, 254, and 256 in P DE significantly affect the antiserum-VP2 affinity. • Residues 252, 254, and 256 play vital roles in nVarIBDV escaping antiserum neutralization, and G254N is the most significant. [ABSTRACT FROM AUTHOR]

Constructing sophisticated hollow structure and exposing more metal sites in metal-organic frameworks (MOFs) can not only enhance their catalytic performance but also endow them with new functions. Herein, we present a facile coordinative reconstruction strategy to transform Ti-MOF polyhedron into nanosheet-assembled hollow structure with a large amount of exposed metal sites. Importantly, the reconstruction process relies on the esterification reaction between the organic solvent, i.e. ethanol and the carboxylic acid ligand, allowing the conversion of MOF without the addition of any other modulators and/or surfactants. Moreover, the surface and internal structure of the reconstructed MOF can be well tuned via altering the conversion time. Impressively, the reconstructed MOF exhibits ∼5.1-fold rate constant compared to the pristine one in an important desulfurization reaction for clean fuels production, i.e. the oxidation of dibenzothiophene. [ABSTRACT FROM AUTHOR]

Artificial intelligence is developing rapidly in the direction of intellectualization and humanization. Recent studies have shown the vulnerability of many deep learning models to adversarial examples, but there are fewer studies on adversarial examples attacking facial expression recognition systems. Human–computer interaction requires facial expression recognition, so the security demands of artificial intelligence humanization should be considered. Inspired by facial expression recognition, we want to explore the characteristics of facial expression recognition adversarial examples. In this paper, we are the first to study facial expression adversarial examples (FEAEs) and propose an adversarial attack method on facial expression recognition systems, a novel measurement method on the adversarial hardness of FEAEs, and two evaluation metrics on FEAE transferability. The experimental results illustrate that our approach is superior to other gradient-based attack methods. Finding FEAEs can attack not only facial expression recognition systems but also face recognition systems. The transferability and adversarial hardness of FEAEs can be measured effectively and accurately. [ABSTRACT FROM AUTHOR]

The avian leukosis virus (ALV) strain DL00766 was isolated from a farm in China. The phylogenetic analysis showed that env had the highest homology with the E subgroup reference strain, ranging from 94.5% to 94.9%, whereas gp85 had the highest homology with the B and E subgroups, which were 89.0% to 91.3% and 91.3% to 91.8%. In addition, point mutation analysis of gp85 showed that a 400 bp long fragment in gp85 of DL00766 had the highest homology with subgroup B, ranging from 90.1% to 97.5%, and only 82.7% to 83.1% with E subgroup. These results indicate, DL00766 may be an AVL subgroup E isolate with a subgroup B-like gp85 region. This is also the first finding that the E subgroup is used as a recombinant subject, and the subgroup B provides a recombinant virus of an exogenous gene. [ABSTRACT FROM AUTHOR]

Online social networks (OSNs) suffer from forged messages. Current studies have typically been focused on the detection of forged messages and do not provide the analysis of the behaviors of message publishers and network strategies to suppress forged messages. This paper carries out the analysis by taking a game theoretic approach, where infinitely repeated games are constructed to capture the interactions between a publisher and a network administrator and suppress forged messages in OSNs. Critical conditions, under which the publisher is disincentivized to publish any forged messages, are identified in the absence and presence of misclassification on genuine messages. Closed-form expressions are established for the maximum number of forged messages that a malicious publisher could publish. Confirmed by the numerical results, the proposed infinitely repeated games reveal that forged messages can be suppressed by improving the payoffs for genuine messages, increasing the cost of bots, and/or reducing the payoffs for forged messages. The increasing detection probability of forged messages or decreasing misclassification probability of genuine messages also has a strong impact on the suppression of forged messages. [ABSTRACT FROM AUTHOR]

Abstract Image captioning aims to describe the content of images with a sentence. It is a natural way for people to express their understanding, but a challenging and important task from the view of image understanding. In this paper, we propose two innovations to improve the performance of such a sequence learning problem. First, we give a new attention method named triple attention (TA-LSTM) which can leverage the image context information at every stage of LSTM. Then, we redesign the structure of basic LSTM, in which not only the stacked LSTM but also the paralleled LSTM are adopted, called as PS-LSTM. In this structure, we not only use the stack LSTM but also use the parallel LSTM to achieve the improvement of the performance compared with the normal LSTM. Through this structure, the proposed model can ensemble more parameters on single model and has ensemble ability itself. Through numerical experiments, on the public available MSCOCO dataset, our final TA-PS-LSTM model achieves comparable performance with some state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Machine learning plays an important role in constructing intrusion detection models. However, the information era is an era of data. With the continuous increase in data size and the growth of data dimensions, the ability of a single classifier is becoming limited in predicting samples. In this paper, we present an ensemble method using random subspace in which an extreme learning machine (ELM) is chosen as the base classifier. To optimize the ensemble model, an ensemble pruning method based on the bat algorithm (BA) is proposed. Meanwhile, a fitness function based on the accuracy and diversity of an ensemble is defined in the BA to obtain an improved classifier subset. Three public datasets, the KDD99, NSL and Kyoto datasets, are adopted to assess the robustness of the method. The empirical results indicate that the ensemble method based on random subspace can improve the accuracy and robustness over the use of an individual ELM. The results also show that compared with when all the sub-classifiers are used in the ensemble, the pruning framework can not only achieve comparable or better performance but also save substantial computing resources in an intrusion detection system (IDS). [ABSTRACT FROM AUTHOR]

Attributed-based encryption (ABE) is a promising cryptographic access control mechanism with a rich expressiveness of ABE policies. Due to the high complexities of encryption and decryption, users are burdened with large computation cost. Fortunately, outsourcing technologies can be used to reduce the computation overhead for the ABE schemes. In the recent decade, the achievements of the outsourced ciphertext-policy ABE (CP-ABE) schemes are inspiring. But, the outsourcing encryption algorithms for CP-ABE schemes are not addressed properly since the encryption exponents are dynamic. In this paper, we present an efficient outsourced CP-ABE scheme with checkability, where the number of the exponential operations in the encryption can be reduced to a constant by introducing a blinding algorithm. Meanwhile, the ciphertext size is not increased. Furthermore, to guarantee the correctness of our scheme, we provide the verification mechanism based on a collision-resistance hash function, which allows the users to efficiently check the validity of messages and outsourced computation results. Besides, the proposed scheme is secure against replayable chosen ciphertext attacks based on Green’s outsourcing security model. Intensive experiments are carried out to illustrate the efficiency of the proposed scheme. [ABSTRACT FROM AUTHOR]

In previous work, imbalanced datasets composed of more benign samples (the majority class) than the malicious one (the minority class) have been widely adopted in Android malware detection. These imbalanced datasets bias learning toward the majority class, so that the minority class examples are more likely to be misclassified. To solve the problem, we propose a new oversampling method called fuzzy–synthetic minority oversampling technique, which is based on fuzzy set theory and the synthetic minority oversampling technique method. As the sample size of the majority class increases relative to that of the minority class, fuzzy–synthetic minority oversampling technique generates more synthetic examples for each minority class examples in the fuzzy region, where the minority examples have a low degree of membership to the minority class and are more likely to be misclassified. Using the new synthetic examples, the classifiers build larger decision regions that contain more minority examples, and they are no longer biased to the majority class. Compared with synthetic minority oversampling technique and Borderline–synthetic minority oversampling technique methods, fuzzy–synthetic minority oversampling technique achieves higher accuracy on both the minority class and the entire datasets. [ABSTRACT FROM AUTHOR]

More and more organizations outsource their data to remote cloud servers (RCSs). Data owners rent the cloud service providers (CSPs) infrastructure to store their unlimited resources by paying fees metered in month or gigabyte. For increasing the availability and scalability of data, the data owners store their data replicas on multiple servers across multiple data centers. Data owners should ensure that the CSPs actually store all their copies according to the service contract. In this paper, we present an efficient dynamic multicopies possession checking scheme that has the following properties: (1) the data owner uses fully homomorphic encryption (FHE) algorithm to generate multiple copies; (2) the scheme supports data block dynamic operation; (3) the scheme supports third-party auditor’s public validation. Finally, security analysis and experimental results show that our scheme can resist forgery, replacement, and replay attack and perform better than some other related scheme published recently. [ABSTRACT FROM AUTHOR]

How to verify the integrity of outsourced data is an important problem in cloud storage. Most of previous work focuses on three aspects, which are providing data dynamics, public verifiability, and privacy against verifiers with the help of a third party auditor. In this paper, we propose an identity-based data storage and integrity verification protocol on untrusted cloud. And the proposed protocol can guarantee fair results without any third verifying auditor. The theoretical analysis and simulation results show that our protocols are secure and efficient. [ABSTRACT FROM AUTHOR]

[Display omitted] • A surface functional group regulation strategy was proposed for H 2 O 2 production. • The optimized CoNCF-HNO 3 exhibits satisfactory 2e− ORR selectivity in acid medium. • Positive correlation between C-O-C content and 2e− ORR selectivity was disclosed. • A sterilization system for water disinfection was developed based on CoNCF-HNO 3. Electrochemical synthesis has emerged as a promising alternative method for industrial production of hydrogen peroxide (H 2 O 2). Although transition metal-nitrogen-carbon moieties have been regarded as efficient catalysts for oxygen reduction reaction (ORR), they are generally established for four-electron (4e−) pathway, rather than two-electron (2e−) one for selective generation of H 2 O 2. Herein, we propose a strategy to achieve cobalt-carbon hybrids with high 2e− selectivity for H 2 O 2 production in acidic media via tailoring their surface structure and coordination environment. The correlation between 2e− ORR selectivity of the fabricated monolithic electrodes, i.e. Co nanoparticles embedded in N-doped oxo carbon framework (CoNCF), and their oxygen-containing functional groups is revealed. In particular, an excellent H 2 O 2 selectivity over 91 % in 0.05 M H 2 SO 4 is achieved, which exceeds most of previously reported 2e− ORR electrocatalysts. Moreover, a sterilization system for water disinfection is constructed, demonstrating potential practical applications. The smart design of multi-active sites and porous monolithic architecture opens a new avenue for preparing advanced electrode for H 2 O 2 generation and other environment/energy-related systems. [ABSTRACT FROM AUTHOR]

This paper presents a Bell-dual-basis-based quantum watermarking protocol composed of three major algorithms: watermark embedding and extracting and the intercepting test. The first two are completed by using the entanglement swapping property of Bell dual basis and the test is accomplished through IBF protocol to guarantee its bottom security. The watermarking protocol is mainly designed for the protection of digital copyright in the existence of classical information. This design finds that the quality of digital contents is not damaged with its zero-watermark attributes when embedding watermarks. [ABSTRACT FROM AUTHOR]

• A novel method that facial expression saliency maps are proposed to generate facial expression adversarial examples. • The OMIM is proposed to help facial expression saliency maps accelerate to generate facial expression adversarial examples. • Our method is superior to other attack methods, such as FGSM, PGD, BIM, CW. The security demands in humanization should be considered as important, because artificial intelligence is developing rapidly in this area. Recent studies have shown the vulnerability of many deep learning models to adversarial examples; however, only a few studies on facial expression adversarial examples have been conducted. Thus, in this paper, we propose a novel method for generating facial expression adversarial examples using facial saliency maps and facial masking maps. Extensive numerical experiments demonstrate the outstanding performance of our method in terms of attack accuracy, structural similarity index measure score, and computational time, compared with other leading methods, such as the fast gradient sign method, projected gradient descent method, and Carlini–Wagner attacks. [ABSTRACT FROM AUTHOR]

Message security and the sender's identity authentication for communication in the open channel is a basic and important technology of the internet. For keeping the message confidential and unforgeable, the sender can use a digital signature algorithm with his private key to sign the message, and then encrypts the signature on the message. Signcryption which was proposed by Zheng et. al in 1997 is a novel cryptographic primitive that simultaneously provides the authentication and encryption in a single logic step and at lower computational costs and communication overheads than the above sign-then-encrypt way. Since then, there are many signcryption schemes proposed. Only recently, a formal security proof model is formalized providing security proof for Zheng's signcryption in the random oracle model. In the ID-based cryptography, the complexity of the managing certificate is reduced. In this work, by combining a multisignature with an ID-based signcryption scheme, we build a security model of multi-signcryption to define confidentiality and unforgeability of the ID-based signcryption scheme and have proposed an ID-based multi-signcryption scheme based on the bilinear pairings to adapt to a multi-user setting. Given a message m, a receiver's identity IDB, and n sender's identities IDA1, IDA2, ... , IDAn, for each sender Ai, it executes the followings steps: randomly pick xi ε Zq to compute Ri = xiP and ωi = xiQIDB; send (Ri, ωi) to the other senders by a secure channel; (3)after receiving the other senders (Ri, ωi), Ai computes ω = e(Ppub, Σωj) to set c = H2(ω)≈m and R = ΣRj; compute Si = xiH4(m) + H3(R,ω)SIDAi, where SIDAi is the private key of sender Ai. Then the resulting ciphertext is (c,S,R). To unsigcrypt the ciphertext (c,S,R) in the sender list L = (IDA1, IDA2, ... , IDAn), the receiver with identity IDB can compute the following steps to recover and verify the message validity. compute ω = e(R,SIDB) and m = H2(ω)≈c, where SIDB is private key of the receiver; accept the message if and only if the following equation holds [image omitted] By security analysis, we show that our scheme satisfies the two important properties of signcryption: confidentiality and unforgeability, and is proven to have been secure in the random oracle model. The security of the scheme is closely related to the Decisional Bilinear Diffie-Hellman assumption and the computational Diffie-Hellman assumption. Finally, by analyzing the efficiency of the scheme, we show that our scheme is very efficient, and only one pairing computation is needed in the signcryption phase, three pairing operators are needed in the unsigncrytion phase, and the ciphertext size is about 420 bits. [ABSTRACT FROM AUTHOR]

Infectious bursal disease virus (IBDV) is a non-enveloped, bi-segmented double-stranded RNA virus and the causative agent of a poultry immunosuppressive disease known as infectious bursal disease (IBD). The novel variant IBDV (nVarIBDV) recently posed a great threat to the development of the poultry industry. In this study, we identified a novel segment-reassortant IBDV strain, IBDV-JS19-14701 (Genotype A2dB3). Phylogenic analysis showed that Segments A and B of IBDV-JS19-14701 were derived from emerging nVarIBDV (Genotype A2dB1) and long-prevalent HLJ0504-like strains (Genotype A3B3) in China, respectively. The pathogenicity of IBDV-JS19-14701 was further evaluated via animal experiments. IBDV-JS19-14701 exhibited a similar virulence to chickens with the nVarIBDV. The identification of this reassortment event is beneficial for understanding the epidemiology of nVarIBDV and will contribute to the efficient prevention and control of IBD. [ABSTRACT FROM AUTHOR]

• A mutated IBDV belonging to genotype A8B1 was identified and designated as IBDV-HeN20-7103. > IBDV-HeN20-7103 showed unique mutation H253Q compared to attenuated IBDV. > IBDV-HeN20-7103 could induce severe bursal lesions. Infectious bursal disease virus (IBDV), the causative agent of infectious bursal disease (IBD), mainly damages the bursa of Fabricius, which is a central immune organ of birds. As an RNA virus, IBDV is prone to mutation owing to a combination of factors including natural selection pressure. In this study, a naturally occurring mutated IBDV associated with bursa damage was identified, IBDV-HeN20-7103 strain, in an infected chicken flock in central China. Its full-length genome was cloned, and sequence analysis showed that the IBDV-HeN20-7103 strain was located along with the attenuated IBDV, which corresponds to genotype A8B1 of the recently proposed classification scheme, on the branch of the phylogenetic tree. The amino acid sequence comparisons further highlighted the specific characteristics of IBDV-HeN20-7103 with mutation H253Q compared to the attenuated strain. Animal experiments showed that IBDV-HeN20-7103 could induce serious bursal lesions without mortality, which revealed a unique cause of disease in this flock. The identification of such a strain reaffirms the complexity of IBDV evolution and prevalence. [ABSTRACT FROM AUTHOR]

• A smart safety early warning system based on improved DV-Hop localization algorithm for WSNs. • Choosing anchor nodes and calculating per-hop distance are different from the original DV-Hop. • Using role-reversing weighted distance correction strategy to upgrade the positioning accuracy. • Using multi-equation selection strategy and centroid location algorithm to reduce locating error. Safety is the primary consideration of underground operation. At present, many large mineral countries are committed to using wireless sensors to reduce the accident rate and prevent casualties and major economic losses through early warning. The existing monitoring and early warning system of wired coal mine can only be used in the main tunnel, while the complex underground working area is still the "blind area" of monitoring and early warning. This paper proposes a smart safety monitoring system based on improved DV-Hop localization algorithm for randomly deployed wireless sensor networks (WSNs), which can position accurate personal tracking in industrial fields, such as mines, underground operations, tunnel engineering, and underground engineering. By choosing anchor nodes and calculating the average per-hop distance between anchor nodes are considerably different from the original DV-Hop. Based on the improved DV-Hop positioning algorithm, the critical safety data related to underground coal mining and associated with the location of the staff can be extracted precisely and analyzed quickly. The simulations show that the enhanced algorithms are able to effectively improve localization accuracy for randomly distributed sensor networks and ensure its safety in complex environment and improve the level of safety production. [ABSTRACT FROM AUTHOR]

The concept of public key encryption with equality test was introduced at CT-RSA 2010. It has been used in many fields, especially in cloud storage. However, the previous schemes do not provide an effective authorization mechanism. To fill this gap, Ma et al. presented a public key encryption with equality test supporting flexible authorization based on the bilinear pairings. Recently, Lin et al. presented a pairing-free scheme that employs quadratic curve to perform the equality tests, which can achieve a trade-off between computational cost and storage space. In this article, we show that the equality test can be better performed by using a straight line, rather than a quadratic curve. Moreover, we simplify the encryption algorithm, as well as reduce the ciphertext storage space. [ABSTRACT FROM AUTHOR]