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Heterostructures play a pivotal role in the design of valley-locked waveguides, facilitating the manipulation of width as an additional degree of freedom. Through this design, we demonstrate the extension of the topological guided modes from the domain wall of topologically nontrivial valley photonic crystals (VPCs) into the trivial VPCs. We propose a C4 impurity to control the states of the light wave transmission in topological valley-locked waveguides through the intervalley scattering of defects in Quantum Valley Spin Hall topological insulators. By rotating the C4 structure, the ON/OFF (0°/45°) state of the valley-locked waveguides can be controlled, effectively serving as a switch component. Furthermore, many unique applications could be devised based on the introduced impurity. Examples include the development of coding channels with arbitrary output ports and energy concentrators with enhanced secondary concentration. The proposed topological valley-locked waveguides with C4 impurity will be beneficial for on-chip integrated photonic networks.

Objective Rock fracturing and its subsequent activations are the most basic tectonic deformation modes. However, the classical fracturing criteria (Coulomb-Mohr criterion, Griffith criterion, and Byerlee sliding-friction law) have different limitations in practical applications. Methods Based on the classical fracturing criteria and the analysis of the physical nature of fracturing generation (extensional fracturing and shear fracturing), combined with the generalized shear activation criterion and long-term research practice, a "generalized fracturing activation criterion" is proposed through theoretical analysis in this paper. Conclusion This criterion can be used to quantitatively determine the possibility and types of fracturing of any medium, under any triaxial stress state, and at any orientation interface (including pre-existing weak surface and non-weakness surface). It unifies the Coulomb-Mohr criterion, Byerlee's law, and Griffith's criterion, and extends fracturing to fracturing activation. Significance The proposed criterion has broad application prospects in the fracturing activation-related resource (such as shale gas and hot, dry rock) exploration and development and prediction and prevention of natural disasters (such as earthquakes and landslides).

Summary: Catalase (CAT) is the main reactive oxygen species (ROS)‐scavenging enzyme in plants and insects. However, it remains elusive whether and how insect saliva CAT suppresses ROS‐mediated plant defense, thereby promoting initial virus transmission by insect vectors.Here, we investigated how leafhopper Recilia dorsalis catalase (RdCAT) was secreted from insect salivary glands into rice phloem, and how it was perceived by rice chaperone NO CATALASE ACTIVITY1 (OsNCA1) to scavenge excessive H2O2 during insect‐to‐plant virus transmission.We found that the interaction of OsNCA1 with RdCAT activated its enzymatic activity to decompose H2O2 in rice plants during leafhopper feeding. However, initial insect feeding did not significantly change rice CATs transcripts. Knockout of OsNCA1 in transgenic lines decreased leafhopper feeding‐activated CAT activity and caused higher H2O2 accumulation. A devastating rice reovirus activated RdCAT expression and promoted the cosecretion of virions and RdCAT into leafhopper salivary cavities and ultimately into the phloem. Virus‐mediated increase of RdCAT secretion suppressed excessive H2O2, thereby promoting host attractiveness to insect vectors and initial virus transmission.Our findings provide insights into how insect saliva CAT is secreted and perceived by plant chaperones to suppress the early H2O2 burst during insect feeding, thereby facilitating viral transmission. [ABSTRACT FROM AUTHOR]

Heterostructures play a pivotal role in the design of valley-locked waveguides, facilitating the manipulation of width as an additional degree of freedom. Through this design, we demonstrate the extension of the topological guided modes from the domain wall of topologically nontrivial valley photonic crystals (VPCs) into the trivial VPCs. We propose a C4 impurity to control the states of the light wave transmission in topological valley-locked waveguides through the intervalley scattering of defects in Quantum Valley Spin Hall topological insulators. By rotating the C4 structure, the ON/OFF (0°/45°) state of the valley-locked waveguides can be controlled, effectively serving as a switch component. Furthermore, many unique applications could be devised based on the introduced impurity. Examples include the development of coding channels with arbitrary output ports and energy concentrators with enhanced secondary concentration. The proposed topological valley-locked waveguides with C4 impurity will be beneficial for on-chip integrated photonic networks. [ABSTRACT FROM AUTHOR]

In order to obtain stable and reliable configuration transformation ability, reliability optimization design is regarded as an effective way to reduce the probability of kinematic function failure for the constrained metamorphic mechanism. Based on the structural composition principle of multi-configuration source metamorphic mechanism that can operate in an under-actuated state, the modularized calculation methods are established for the force analysis of augmented Assur groups including metamorphic kinematic joints. According to the equivalent resistance gradient model of metamorphic mechanisms, with considering the uncertainties in the link dimensions, masses, and compliance parameters et al., a probabilistic evaluation method for describing the configuration transformation ability of the constrained metamorphic mechanism is established. Based on reliability evaluation and reliability sensitivity analysis, a reliability optimization design method for improving the configuration transformation ability is proposed, and then the optimization design is carried out for tolerances of random variables focusing on those structural parameters with higher reliability sensitivity, so that the optimized results can satisfy the requirements of both reliability and economic simultaneously. Finally, the feasibility and effectiveness of the proposed method is verified by the illustration of a paper folding metamorphic mechanism. The research provides the foundation of reliability design of metamorphic mechanisms to obtain the high-probability repeated execution ability of configuration transformation, it also has theoretical and practical significance to promote the engineering application of metamorphic mechanisms. [ABSTRACT FROM AUTHOR]

Simple Summary: Parasite diseases are recognized as major concerns in the fugu aquaculture industry in China. While understanding the genetic mechanisms of immune response is a crucial step which can facilitate disease control and selective breeding. In this study, transcriptome analysis was performed to identify key genes and understand the underlying mechanisms associated with Cryptocaryon irritans resistance. Finally, our study provided insights into the immunosuppression in fugu under C. irritans infection. The tiger pufferfish (Takifugu rubripes), also known as fugu, has recently suffered from severe C. irritans infections under aquaculture environment, yet the underlying immune mechanisms against the parasite remain poorly understood. In this study, we conducted a comprehensive transcriptome analysis of the gill tissue from infected and uninfected fish using PacBio long-read (one pooled sample each for seriously infected and healthy individuals, respectively) and Illumina short-read (three pools for mildly infected, seriously infected, and healthy individuals, respectively) RNA sequencing technologies. After aligning sequence data to fugu's reference genome, 47,307 and 34,413 known full-length transcripts were identified and profiled in healthy and infected fish, respectively. Similarly, we identified and profiled 1126 and 803 novel genes that were obtained from healthy and infected fish, respectively. Interestingly, we found a decrease in the number of alternative splicing (AS) events and long non-coding RNAs (lncRNAs) after infection with C. irritans, suggesting that they may be involved in the regulation of the immune response in fugu. There were 687 and 1535 differentially expressed genes (DEGs) in moderately and heavily infected fish, respectively, compared to uninfected fish. Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that immune-related DEGs in the two comparison groups were mainly enriched in cytokine-cytokine receptor interactions, ECM-receptor interactions, T-cell receptor signaling pathways, Th1 and Th2 cell differentiation, and Th17 cell differentiation pathways. Further analysis revealed that a large number of immune-related genes were downregulated in infected fish relative to uninfected ones, such as CCR7, IL7R, TNFRSF21, CD4, COL2A1, FOXP3B, and ITGA8. Our study suggests that C. irritans is potentially a highly efficient parasite that may disrupt the defense mechanisms of fugu against it. In addition, in combination of short-read RNA sequencing and previous genome-wide association analyses, we identified five key genes (NDUFB6, PRELID1, SMOX, SLC25A4, and DENND1B) that might be closely associated with C. irritans resistance. This study not only provides valuable resources of novel genic transcripts for further research, but also provides new insights into the immune mechanisms underlying C. irritans infection response in farmed fugu. [ABSTRACT FROM AUTHOR]

Tamarix hispida Willd. 1816, a crucial native plant species in the arid desert region of northwestern China, plays a significant role in maintaining ecological stability. It is instrumental in addressing soil salinity–alkalinity and heavy metal pollution. This research aims to analyze the phylogenetic divergence pattern and evolutionary history of T. hispida by comparing chloroplast genome structures across different populations. Despite the minimal differences in chloroplast genome structure due to conserved genes and junction regions, sequencing was conducted using the Illumina NovaSeq platform to verify the historical evolutionary processes between different populations, followed by assembly and annotation. The results revealed that the T. hispida chloroplast genome is approximately 156,164–156,186 bp in length, with a quadripartite structure and 131 annotated genes. Phylogenetic analysis indicated two lineages within T. hispida, with a divergence time of 3.15 Ma. These findings emphasize the low genetic diversity in T. hispida and offer valuable insights into its evolutionary past. To effectively protect and manage this species, increased scientific research and monitoring of its genetic diversity are necessary. This study underscores the importance of comprehending the genetic mechanisms behind species divergence to develop informed conservation strategies. [ABSTRACT FROM AUTHOR]

BackgroundArid and semi-arid regions account for about 40% of the world’s land surface area, and are the most sensitive areas to climate change, leading to a dramatic expansion of arid regions in recent decades. Ephemeral plants are crucial herbs in this area and are very sensitive to climate change, but it is still unclear which factors can determine the distribution of ephemeral plants and how the distribution of ephemeral plants responds to future climate change across the globe.AimsUnderstanding the impact of climate change on ephemeral plant distribution is crucial for sustainable biodiversity conservation.MethodsThis study explored the potential distribution of three types of ephemeral plants in arid and semi-arid regions (cold desert, hot desert, and deciduous forest) on a global scale using the MaxEnt software. We used species global occurrence data and 30 environmental factors in scientific collections.ResultsOur results showed that (1) the average value of the area under the receiver operating curve (AUC) of each species was higher than 0.95, indicating that the MaxEnt model’s simulation accuracy for each species was good; (2) distributions of cold desert and deciduous forest species were mainly determined by soil pH and annual mean temperature; the key factor that determines the distribution of hot desert species was precipitation of the driest month; and (3) the potential distribution of ephemeral plants in the cold desert was increased under one-third of climate scenarios; in the hot desert, the potential suitable distribution for Anastatica hierochuntica was decreased in more than half of the climate scenarios, but Trigonella arabica was increased in more than half of the climate scenarios. In deciduous forests, the ephemeral plant Crocus alatavicus decreased in nearly nine-tenths of climate scenarios, and Gagea filiformis was increased in 75% of climate scenarios.ConclusionsThe potential suitable distributions of ephemeral plants in the different ecosystems were closely related to their specific adaptation strategies. These results contribute to a comprehensive understanding of the potential distribution pattern of some ephemeral plants in arid and semi-arid ecosystems.