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Fungal effectors play critical roles in manipulating plant immune responses and promoting colonization. Sphaerulina musiva is a heterothallic ascomycete fungus that causes Septoria leaf spot and stem canker disease in poplar (Populus spp.) plantations. This disease can result in premature defoliation, branch and stem breakage, increased mortality, and plantation failure. However, little is known about the interaction between S. musiva and poplar. Previous work predicted 142 candidate secreted effector proteins in S. musiva (SmCSEPs), 19 of which were selected for further functional characterization in this study. SmCSEP3 induced plant cell death in Nicotiana benthamiana, while 8 out of 19 tested SmCSEPs suppressed cell death. The signal peptides of these eight SmCSEPs exhibited secretory activity in a yeast signal sequence trap assay. Confocal microscopy revealed that four of these eight SmCSEPs target both the cytoplasm and the nucleus, whereas four predominantly localize to discrete punctate structures. Pathogen challenge assays in N. benthamiana demonstrated that the transient expression of six SmCSEPs promoted Fusarium proliferatum infection. The expression of these six SmCSEP genes were induced during infection. SmCSEP2, SmCSEP13, and SmCSEP25 suppressed chitin-triggered reactive oxygen species burst and callose deposition in N. benthamiana. The candidate secreted effector proteins of S. musiva target multiple compartments in the plant cell and modulate different pattern-triggered immunity pathways. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2023.

Constructing coastal ecological security barriers is beneficial for preventing environmental degradation and enhancing resilience to natural disasters. This study examines the functionality of these barriers from an ecosystem service perspective, developing an Ecosystem Security Barrier Function (ESBF) index to analyze its spatiotemporal variations. From 2000 to 2020, habitat quality in the study area experienced a slight decline, while water supply capacity initially increased and then decreased. Water purification capacity hit its lowest point in 2015 before improving. The ESBF generally ranged from moderate to high levels, with higher values in the northwest and lower values in the southeast, showing strong spatial autocorrelations. Despite mild degradation in some areas, overall stability was maintained with frequent transitions between ESBF levels. Utilizing the Multiscale Geographically Weighted Regression (MGWR) model, we conducted a grid-scale analysis of the driving mechanisms behind ESBF. We found that precipitation, elevation, and the Normalized Difference Vegetation Index (NDVI) positively correlated with ESBF, whereas population density, land use, and nighttime lights negatively correlated. The relationship between temperature and ESBF showed a "north-positive, south-negative" pattern. The study recommends enhancing coastal wetland restoration, strengthening protective forest construction, and effectively controlling pollutant sources entering the sea to safeguard and improve the ecological security barrier function. [ABSTRACT FROM AUTHOR]

This article provides an analysis of Oomycete Nudix effectors, which are proteins secreted by phytopathogens to aid in the colonization of host plants. The researchers conducted a phylogenetic analysis and examined the crystal structure of the P. sojae effector Avr3b. They found that oomycete Nudix effectors have distinct structural features and functions compared to fungal and bacterial Nudix effectors. The study also revealed that Avr3b and other oomycete Nudix effectors have mRNA decapping activity, suggesting their involvement in modulating host immune responses. Further research is needed to fully understand the role of these effectors in promoting pathogen infection and their impact on host immunity. [Extracted from the article]

Buffer energy absorbing structures have very high use value in daily life, industrial production, aerospace and other fields. Cylindrical shells are used as a highly efficient buffer and energy absorbing structure due to their own structure and good mechanical properties. Taylor impact experiments were conducted on three types of structural cylindrical shells (non grooved, inner grooved, and outer grooved) and numerical model was also established to study and analyze the dynamic response characteristics of the three types of structural cylindrical shells. Finally, the deformation mechanism of the cylindrical shell was analyzed theoretically to explore the impact of grooving treatment on the deformation of the cylindrical shell. The results show that with the increase of impact velocity, the length of the cylindrical shells of the three structures decreased, and the diameter of the impact end and the maximum diameter increased. Each of the three specimens had a convergence velocity(convergence velocity: The impact end diameter of cylindrical shell is the initial impact velocity at the maximum diameter), that is, when the impact velocity was greater than or equal to the convergence velocity, its maximum diameter was equal to the diameter of the impact end. When the impact velocity exceeded a certain value, the deformation modes of the three types of cylindrical shells changed. The comparison of experimental and simulation results proved the effectiveness of the numerical model. The maximum stress was always above the impact end face. It was concluded from the theoretical analysis Due to the stress concentration at the groove, the stress distribution and internal stress distribution of the cylindrical shell were affected, which in turn affected the deformation and energy absorption capacity of the cylindrical shell. At the same impact velocity, the outer grooved cylindrical shell has the shortest buffer time and the BW specimen had the most gentle buffer curve before 35μs. [ABSTRACT FROM AUTHOR]

Quasi-static compression/tension, dynamic compression/shear mechanical property tests, fracture morphology characterization, dynamic response experiment, numerical simulation, and calculation of the ultimate penetration velocity of the high-strength steel under the impact of large mass low-velocity fragments and small mass high-velocity fragments were carried out to study the ballistic performance of high-strength steel used for armor vehicle protection and clarify its dynamic response under Ballistic impact. The fracture mode of the high-strength steel under dynamic impact compression and shear was shear failure. A large number of fine parabolic shear dimples were formed on the fracture surface. The high-strength steel had an obvious strain rate strengthening effect and adiabatic shear sensitivity. The plug formed under the low-velocity impact of a large mass fragment was a cone shape, and the impact area of the target plate underwent slight bending plastic deformation. The damage of the fragment to the target plate includes both adiabatic shear failure and ordinary shear failure. Under the high-velocity impact of small mass fragments, the fragments were seriously deformed and destroyed, and the damage model of the target plate is adiabatic shear failure. [ABSTRACT FROM AUTHOR]

The petrogenesis and geodynamic setting of the Mesozoic magmatic rocks in the Erguna Block, NE China remains controversial, especially the relationship between magmatism and the subduction history of the Mongol–Okhotsk oceanic plate. Here we present data for the Early Jurassic–Early Cretaceous adakite-like magmatic rocks from Chaoman Farm in the northeastern part of the Erguna Block. Zircon U-Pb dating reveals that the syenogranites crystallized at around 190–180 Ma, while the monzonites, quartz diorite porphyries, and quartz monzonite porphyries were emplaced at around 147–143 Ma. The syenogranites, monzonites, quartz diorite porphyries, and quartz monzonite porphyries are adakite-like rocks. The syenogranites and quartz monzonite porphyries were produced by the partial melting of a thickened ancient mafic lower continental crust and a thickened juvenile lower crust, respectively. Meanwhile, the monzonites and quartz diorite porphyries were formed as a result of partial melting of the oceanic crust. In conclusion, the occurrence of these Early Jurassic magmatic rocks was closely linked to the process of southward subduction of the Mongol–Okhotsk oceanic plate. On the contrary, the Late Jurassic to early Early Cretaceous magmatism (147–143 Ma) occurred in an extensional environment, and was probably triggered by upwelling of the asthenosphere. [ABSTRACT FROM AUTHOR]