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Towards the universal defense for query-based audio adversarial attacks on speech recognition system

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Cybersecurity 2024年第1期7卷 53-70页

作者： Feng Guo Zheng Sun Yuxuan Chen Lei Ju School of Cyber Science and Technology Shandong UniversityQingdaoChina Quancheng Laboratory QCLJinanChina

Recently,studies show that deep learning-based automatic speech recognition(ASR)systems are vulnerable to adversarial examples(AEs),which add a small amount of noise to the original audio examples.These AE attacks pose new challenges to deep learning security and have raised significant concerns about deploying ASR systems and devices.The existing defense methods are either limited in application or only defend on results,but not on process.In this work,we propose a novel method to infer the adversary intent and discover audio adversarial examples based on the AEs generation process.The insight of this method is based on the observation:many existing audio AE attacks utilize query-based methods,which means the adversary must send continuous and similar queries to target ASR models during the audio AE generation process.Inspired by this observation,We propose a memory mechanism by adopting audio fingerprint technology to analyze the similarity of the current query with a certain length of memory query.Thus,we can identify when a sequence of queries appears to be suspectable to generate audio AEs.Through extensive evaluation on four state-of-the-art audio AE attacks,we demonstrate that on average our defense identify the adversary’s intent with over 90%accuracy.With careful regard for robustness evaluations,we also analyze our proposed defense and its strength to withstand two adaptive attacks.Finally,our scheme is available out-of-the-box and directly compatible with any ensemble of ASR defense models to uncover audio AE attacks effectively without model retraining.

关键词： Adversarial attacks defense Memory mechanism Query-based

Attacks Against Cross-Chain Systems and defense Approaches:A Contemporary Survey

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IEEE/CAA Journal of Automatica Sinica 2023年第8期10卷 1647-1667页

作者： Li Duan Yangyang Sun Wei Ni Weiping Ding Jiqiang Liu Wei Wang IEEE the Beijing Key Laboratory of Security and Privacy in Intelligent Transportation Beijing Jiaotong UniversityBeijing 100044China the Guangxi Key Laboratory of Cryptography and Information Security Guilin 541004China the Communications and Signal Processing Team Data61 Business UnitCommonwealth Scientific and Industrial Research Organisation(CSIRO)Sydney NSW 2109Australia the School of Information Science and Technology Nantong UniversityNantong 226019China

The blockchain cross-chain is a significant technology for inter-chain interconnection and value transfer among different blockchain networks.Cross-chain overcomes the“information island”problem of the closed blockchain network and is increasingly applied to multiple critical areas such as finance and the internet of things(IoT).Blockchain can be divided into three main categories of blockchain networks:public blockchains,private blockchains,and consortium blockchains.However,there are differences in block structures,consensus mechanisms,and complex working mechanisms among heterogeneous blockchains.The fragility of the cross-chain system itself makes the cross-chain system face some potential security and privacy threats.This paper discusses security defects on the cross-chain implementation mechanism,and discusses the impact of the structural features of blockchain networks on cross-chain security.In terms of cross-chain intercommunication,a cross-chain attack can be divided into a multi-chain combination attack,native chain attack,and inter-chain attack diffusion.Then various security threats and attack paths faced by the cross-chain system are analyzed.At last,the corresponding security defense methods of cross-chain security threats and future research directions for cross-chain applications are put forward.

关键词： Blockchain cross-chain defense distributed private key control hash-locking notary security threats sidechain/relay

Diurnal emission of herbivore-induced(Z)-3-hexenyl acetate and allo-ocimene activates sweet potato defense responses to sweet potato weevils

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Journal of Integrative Agriculture 2023年第6期22卷 1782-1796页

作者： XIAO Yang-yang QIAN Jia-jia HOU Xing-liang ZENG Lan-ting LIU Xu MEI Guo-guo LIAO Yin-yin Guangdong Provincial Key Laboratory of Digital Botanical Garden and Popular Science/Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement South China Botanical GardenChinese Academy of SciencesGuangzhou 510650P.R.China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China Center of Economic Botany Core Botanical GardensChinese Academy of SciencesGuangzhou 510650P.R.China

The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However, no safe and effective methods have been found to protect sweet potato from this pest. Herbivore-induced plant volatiles(HIPVs)promote various defensive bioactivities, but their formation and the defense mechanisms in sweet potato have not been investigated. To identify the defensive HIPVs in sweet potato, the release dynamics of volatiles was monitored.The biosynthetic pathways and regulatory factors of the candidate HIPVs were revealed via stable isotope tracing and analyses at the transcriptional and metabolic levels. Finally, the anti-insect activities and the defense mechanisms of the gaseous candidates were evaluated. The production of(Z)-3-hexenyl acetate(z3HAC) and allo-ocimene was induced by sweet potato weevil feeding, with a distinct circadian rhythm. Ipomoea batatas ocimene synthase(IbOS) is first reported here as a key gene in allo-ocimene synthesis. Insect-induced wounding promoted the production of the substrate,(Z)-3-hexenol, and upregulated the expression of IbOS, which resulted in higher contents of z3HAC and allo-ocimene,respectively. Gaseous z3HAC and allo-ocimene primed nearby plants to defend themselves against sweet potato weevils. These results provide important data regarding the formation, regulation, and signal transduction mechanisms of defensive volatiles in sweet potato, with potential implications for improving sweet potato weevil management strategies.

关键词： sweet potato (Z)-3-hexenyl acetate allo-ocimene defense signaling

Identification of atypical T4SS effector proteins mediating bacterial defense

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mLife 2023年第3期2卷 295-307页

作者： Xi Shen Zixiang Yang Zihan Li Dan Xiong Jinxing Liao Weimei He Danyu Shen Xiaolong Shao Ben Niu Yongxing He Yong-Gui Gao Guoliang Qian State Key Laboratory of Biological Interactions and Crop Health Key Laboratory of Integrated Management of Crop Diseases and PestsCollege of Plant ProtectionNanjing Agricultural UniversityNanjingChina College of Life Science Northeast Forestry UniversityHarbinChina Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations Lanzhou UniversityLanzhouChina School of Biological Sciences Nanyang Technological UniversitySingaporeSingapore

To remain competitive,proteobacteria use various contact-dependent weapon systems to defend against microbial com-petitors.The bacterial-killing type IV secretion system(T4SS)is one such powerful weapon.It commonly controls the killing/competition between species by secreting the lethal T4SS effector(T4E)proteins carrying conserved XVIPCD domains into competing cells.In this study,we sought knowledge to understand whether the bacterial-killing T4SS-producing bacteria encode T4E-like proteins and further explore their biological functions.To achieve this,we designed a T4E-guided approach to discover T4E-like proteins that are designated as atypical T4Es.Initially,this approach required scientists to perform simple BlastP search to identify T4E homologs that lack the XVIPCD domain in the genomes of T4SS-producing bacteria.These homologous genes were then screened in Escherichia coli to identify antibacterial candidates(atypical T4Es)and their neighboring detoxification proteins,followed by testing their gene cotranscription and validating their physical interactions.Using this approach,we did discover two atypical T4E proteins from the plant-beneficial Lysobacter enzymogenes and the phytopathogen Xanthomonas citri.We also provided substantial evidence to show that the atypical T4E protein Le1637-mediated bacterial defense in interspecies interactions between L.enzymogenes and its competitors.Therefore,the newly designed T4E-guided approach holds promise for detecting functional atypical T4E proteins in bacterial cells.

关键词： atypical effectors defense immunity protein T4SS toxic

A shield of defense:Developing ballistic composite panels with effective electromagnetic interference shielding absorption

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Defence Technology（防务技术） 2024年第5期35卷 123-136页

作者： Nisrin Rizek Abdelal Mechanical Engineering Department Jordan University of Science and TechnologyIrbid 22110Jordan

The primary goal of this study is to develop cost-effective shield materials that offer effective protection against high-velocity ballistic impact and electromagnetic interference(EMI)shielding capabilities through absorption.Six fiber-reinforced epoxy composite panels,each with a different fabric material and stacking sequence,have been fabricated using a hand-layup vacuum bagging process.Two panels made of Kevlar and glass fibers,referred to as(K-NIJ)and(G-NIJ),have been tested according to the National Institute of Justice ballistic resistance protective materials test NIJ 0108.01 Standard-Level IIIA(9 mm×19 mm FMJ 124 g)test.Three panels,namely,a hybrid of Kevlar and glass(H-S),glass with ceramic particles(C-S),and glass with recycled rubber(R-S)have been impacted by the bullet at the center,while the fourth panel made of glass fiber(G-S)has been impacted at the side.EMI shielding properties have been measured in the X-band frequency range via the reflection-transmission method.Results indicate that four panels(K-NIJ,G-NIJ,H-S,and G-S)are capable of withstanding high-velocity impact by stopping the bullet from penetrating through the panels while maintaining their structural integrity.However,under such conditions,these panels may experience localized delamination with variable severity.The EMI measurements reveal that the highest absorptivity observed is 88% for the KNIJ panel at 10.8 GHz,while all panels maintain an average absorptivity above 65%.All panels act as a lossy medium with a peak absorptivity at different frequencies,with K-NIJ and H-S panels demonstrating the highest absorptivity.In summary,the study results in the development of a novel,costeffective,multifunctional glass fiber epoxy composite that combines ballistic and electromagnetic interference shielding properties.The material has been developed using a simple manufacturing method and exhibits remarkable ballistic protection that outperforms Kevlar in terms of shielding efficiency;no bullet penetration or back face signature is observed,

关键词： Ballistic FRP composite EMI shielding Absorptivity CT-Scan NIJ test Bullet defense

Identification of two clip domain serine proteases involved in the pea aphid's defense against bacterial and fungal infection

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Insect Science 2020年第4期27卷 735-744页

作者： Li Ma Feng Chen Wen Wang Lu Xu Zhi-Qiang Lu Department of Entomology College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxiChina Key Laboratory of Plant Protection Resources and Pest Management Ministry of EducationNorthwest A&F UniversityYanglingShaanxiChina

Phenoloxidases(POs)are required for the pea aphid s defense against bacterial and fungal infection.Prophenoloxidases(PPOs)are protcolytically converted to its active form PO through a clip domain serine protease cascade.In this study,we identified five clip domain serine proteases in the pea aphids.The messenger RNA levels of two of them,Ap.SPLP and Ap_VP,were upregulated by Gram-positive bacterium Staphylococcus aureus and fungus Beauveha bassiana infections.Double-stranded RNA-based expression knockdown of these two genes resulted in reduced PO activity of the aphid hemolymph,higher loads of S.aureus and B.bassiana in the aphids,and lower survival rates of the aphids after infections.Our data suggest that Ap.SPLP and Ap_VP are involved in PPO activation pathway in the pea aphid.

关键词： defense pea aphid prophenoloxidase RNA interference serine proteases

Arabidopsis DXO1 possesses deNADding and exonuclease activities and its mutation affects defense-related and photosynthetic gene expression^FA

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Journal of Integrative Plant Biology 2020年第7期62卷 967-983页

作者： Shuying Pan Kai-en Li Wei Huang Huan Zhong Huihui Wu Yuan Wang He Zhang Zongwei Cai Hongwei Guo Xuemei Chen Yiji Xia Department of Biology Hong Kong Baptist UniversityHong KongChina State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong KongChina Department of Biology Southern University of Science and TechnologyShenzhen 518055China Department of Botany and Plant Sciences Institute of Integrative Genome BiologyUniversity of CaliforniaRiversideCalifornia 92521USA State Key Laboratory of Agricultural Biotechnology School of Life SciencesChinese University of Hong KongHong KongChina

RNA capping and decapping tightly coordinate with transcription,translation,and RNA decay to regulate gene expression.Proteins in the DXO/Rai1 family have been implicated in mRNA decapping and decay,and mammalian DXO was recently found to also function as a decapping enzyme for NAD+-capped RNAs(NAD-RNA).The Arabidopsis genome contains a single gene encoding a DXO/Rai1 protein,AtDXO1.Here we show that AtDXO1 possesses both NAD-RNA decapping activity and 5?-3?exonuclease activity but does not hydrolyze the m7G cap.The atdxo1 mutation increased the stability of NAD-RNAs and led to pleiotropic phenotypes,including severe growth retardation,pale color,and multiple devel-opmental defects.Transcriptome profiling analysis showed that the atdxo1 mutation resulted in upregulation@of defense-related genes but downregulation of photo-synthesis-related genes.The autoimmunity phenotype of the mutant could be suppressed by either eds1 or npr1 mutation.However,the various phenotypes associated with the atdxo1 mutant could be complemented by an enzymatically inactive AtDXO1.The atdxo1 mutation ap-parently enhances post-transcriptional gene silencing by elevating levels of siRNAs.Our study indicates that AtDXO1 regulates gene expression in various biological and physiological processes through its pleiotropic mo-lecular functions in mediating RNA processing and decay.

关键词： decay Arabidopsis defense

Common mycorrhizal networks activate salicylic acid defense responses of trifoliate orange(Poncirus trifoliata)

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Journal of Integrative Plant Biology 2019年第10期61卷 1099-1111页

作者： Yi-Can Zhang Ying-Ning Zou Li-Ping Liu Qiang-Sheng Wu College of Horticulture and Gardening Yangtze University Jingzhou 434025 China Institute of Root Biology Yangtze University Jingzhou 434025 China Department of Chemistry Faculty of Science University of Hradec Kralove Hradec Kralove 50003 Czech Republic

Citrus canker, caused by Xanthomonas axonopo-dis pv. citri ('Xac'), is an important quarantine disease in citrus crops. Arbuscular mycorrhizal fungi (AMF) form symbiotic interactions with host plants and further affect their disease resistance, possibly by modulating the activity of salicylic acid (SA), a key phytohormone in disease resistance. Common mycorrhizal networks (CMNs) can interconnect plants, but it is not yet clear whether CMNs promote resistance to citrus canker and, if so, whether SA signaling is involved in this process. To test this possibility, we used a two-chambered rootbox to establish CMNs between trifoliate orange (Poncirus trifoliata) seedlings in chambers inoculated (treated) or not (neighboring) with the AMF, Paraglomus occultum. A subset of the AMF-inoculated seedlings were also inoculated with Xac (+AMF+Xac). At 2 d post-inoculation (dpi), compared with the +AMF-Xac treatment, neighboring seedlings in +AMF+Xac treatment had lower expression levels of the SA biosynthetic genes, PtPAL, PtEPS1, and PtPBS3, but higher SA levels, which attributed to the upregulation of PtPAL and PtPBS3 in treated seedlings and the transfer of SA, via CMNs, to the neighboring seedlings. At 4 dpi, the pathogenesis-related (PR) protein genes, PtPR1, PtPR4, and PtPR5, and the transcriptional regulatory factor gene, PtNPR1, were activated in neighboring seedlings of+AMF+Xac treatment. At 9 dpi, root phenylalanine ammo-nia-lyase activity and total soluble phenol and lignin concentrations increased in neighboring seedlings of+AMF+Xac treatment, likely due to the linkage and signal transfer, via CMNs. These findings support the hypothesis that CMNs transfer the SA signal from infected to neighboring healthy seedlings, to activate defense responses and affording protection to neighboring plants against citrus canker infection.

关键词： Poncirus trifoliata mycorrhizal salicylic acid defense responses

Effect of temperature on antioxidant defense and innate immunity in Brandt’s voles

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Zoological Research 2019年第4期40卷 305-316页

作者： De-Li Xu Meng-Meng Xu De-Hua Wang College of Life Sciences Qufu Normal UniversityQufu Shandong 273165China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China

Ambient temperature is an importa nt factor in flue ncing many physiological processes, in eluding antioxidant defense and immunity. In the present study, we tested the hypothesis that antioxidant defense and immunity are suppressed by high and low temperature treatme nt in Bran dt's voles (Lasiopodomys brandtii). Thirty male voles were randomly assigned into different temperature groups (4, 23, and 32℃, n=10 for each group), with the treatment course lasting for 27 d. Results showed that low temperature in creased gross en ergy in take (GEI) and liver, heart, and kidney mass, but decreased body fat mass and dry carcass mass. With the decline in temperature, hydrogen peroxide (H2O2) concentration, which is indicative of reactive oxyge n species (ROS) levels, in creased in the liver, decreased in the heart, and was unchanged in the kidney, testis, and small intestine. Lipid peroxidation indicated by malonaldehyde (MDA) content in the liver, heart, kidney, testis, and small intestine did not differ among groups, implying that high and low temperature did not cause oxidative damage. Similarly, superoxide dismutase (SOD) and catalase (CAT) activities and total antioxidant capacity (TAOC) in the five tissues did not respond to low or high temperature, except for elevation of CAT activity in the testis upon cold exposure. Bacteria killing capacity, which is indicative of innate immunity, was nearly suppressed in the 4℃ group in contrast to the 23℃ group, whereas spleen mass and white blood cells were un affected by temperature treatment. The levels of testosterone, but not corticostero ne, were in flue need by temperature treatment, though neither were correlated with innate immunity, H2O2 and MDA levels, or SOD, CAT, and TAOC activity in any detected tissues. Overall, these results showed that temperature had different in flue nces on oxidative stress, an tioxida nt en zymes, and immunity, which depended on the tissues and parameters tested. Up-regulation or maintenance of an tioxida nt defe nse might be an importa nt

关键词： Antioxidant defense Brandt's voles(Lasiopodomys brandtii) Immunity Temperature