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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]

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]

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]

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]

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]

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]

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]