57 research outputs found

    Layer Construction of Three-Dimensional Z2 Monopole Charge Nodal Line Semimetals and prediction of the abundant candidate materials

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    The interplay between symmetry and topology led to the concept of symmetry-protected topological states, including all non-interacting and weakly interacting topological quantum states. Among them, recently proposed nodal line semimetal states with space-time inversion (PT\mathcal{PT}) symmetry which are classified by the Stiefel-Whitney characteristic class associated with real vector bundles and can carry a nontrivial Z2\mathbb{Z}_2 monopole charge have attracted widespread attention. However, we know less about such 3D Z2\mathbb{Z}_2 nodal line semimetals and do not know how to construct them. In this work, we first extend the layer construction previously used to construct topological insulating states to topological semimetallic systems. We construct 3D Z2\mathbb{Z}_2 nodal line semimetals by stacking of 2D PT\mathcal{PT}-symmetric Dirac semimetals via nonsymmorphic symmetries. Based on our construction scheme, effective model and combined with first-principles calculations, we predict two types of candidate electronic materials for Z2\mathbb{Z}_2 nodal line semimetals, namely 14 Si and Ge structures and 108 transition metal dichalcogenides MX2MX_2 (MM=Cr, Mo, W, XX=S, Se, Te). Our theoretical construction scheme can be directly applied to metamaterials and circuit systems. Our work not only greatly enriches the candidate materials and deepens the understanding of Z2\mathbb{Z}_2 nodal line semimetal states but also significantly extends the application scope of layer construction

    ALL-MASK: A Reconfigurable Logic Locking Method for Multicore Architecture with Sequential-Instruction-Oriented Key

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    Intellectual property (IP) piracy has become a non-negligible problem as the integrated circuit (IC) production supply chain is becoming increasingly globalized and separated that enables attacks by potentially untrusted attackers. Logic locking is a widely adopted method to lock the circuit module with a key and prevent hackers from cracking it. The key is the critical aspect of logic locking, but the existing works have overlooked three possible challenges of the key: safety of key storage, easy key-attempt from interface and key-related overheads, bringing the further challenges of low error rate and small state space. In this work, the key is dynamically generated by utilizing the huge space of a CPU core, and the unlocking is performed implicitly through the interconnection inside the chip. A novel low-cost logic reconfigurable gate is together proposed with ferroelectric FET (FeFET) to mitigate the reverse engineering and removal attack. Compared to the common logic locking methods, our proposed approach is 19,945 times more time consuming to traverse all the possible combinations in only 9-bit-key condition. Furthermore, our technique let key length increases this complexity exponentially and ensure the logic obfuscation effect.Comment: 15 pages, 17 figure

    The secreted FolAsp aspartic protease facilitates the virulence of Fusarium oxysporum f. sp. lycopersici

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    Pathogens utilize secretory effectors to manipulate plant defense. Fusarium oxysporum f. sp. lycopersici (Fol) is the causal agent of Fusarium wilt disease in tomatoes. We previously identified 32 secreted effector candidates by LC-MS analysis. In this study, we functionally identified one of the secreted proteins, FolAsp, which belongs to the aspartic proteases (Asp) family. The FolAsp was upregulated with host root specifically induction. Its N-terminal 1–19 amino acids performed the secretion activity in the yeast system, which supported its secretion in Fol. Phenotypically, the growth and conidia production of the FolAsp deletion mutants were not changed; however, the mutants displayed significantly reduced virulence to the host tomato. Further study revealed the FolAsp was localized at the apoplast and inhibited INF1-induced cell death in planta. Meanwhile, FolAsp could inhibit flg22-mediated ROS burst. Furthermore, FolAsp displayed protease activity on host protein, and overexpression of FolAsp in Fol enhanced pathogen virulence. These results considerably extend our understanding of pathogens utilizing secreted protease to inhibit plant defense and promote its virulence, which provides potential applications for tomato improvement against disease as the new drug target
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