Background Nudix hydrolases are widely distributed across all classes of organisms and provide the potential capacity to hydrolyze a wide range of organic pyrophosphates. Although Nudix hydrolases are involved in plants detoxification processes in response to abiotic and biotic stresses, the biological functions of Nudix hydrolases remain largely unclear in grapevine. Results A total of 25 putative grapevine Nudix hydrolases ( VvNUDXs ) were identified by bioinformatics analysis and classified into eight subfamilies based to their preferred substrates. Both tandem and segmental duplications were responsible for the evolution and expansion of NUDX gene family in grapevine. To investigate into their regulatory roles of VvNUDX genes during growth and development as well as in response to abiotic and biotic stress in grapevine, the expression patterns were revealed in publicly available microarray data. The spatial and temporal expression patterns of VvNUDX genes indicated that these genes might play important roles in multiple developmental processes. Transcriptome and qRT-PCR analysis exhibited that ten VvNUDX genes were specifically expressed in grapevine berries, suggesting the potential roles in grapevine berry development. Expression and phylogenetic analysis demonstrated that VvNUDX1 and VvNUDX3 might be involved in terpenoid biosynthesis in grapevine. Futhermore, most VvNUDX genes toward the ADP-ribose/NADH were different patterns in response to various abiotic and biotic stresses, such as salinity and drought, as well as different types of biotic treatments, such as Erysiphe necator , Bois Noir phytoplasma and leaf-roll-associated virus-3 (GLRaV-3). Conclusions These results showed that VvNUDX were associated with plant detoxification processes in response to abiotic and biotic stresses, and regulate disease immunity and resistance pathways. The present informations may provide good opportunities to explore the physiological functions of VvNUDX genes in berry development and stress response networks in grapevine.

The effect of copper-coated carbon fiber (Cf) on the foaming behavior of aluminum foam prepared by the powder metallurgy (PM) method, was studied, by using the synchrotron radiation technique. The corresponding stabilizing mechanism of the Cf was discussed and analyzed, by a comparison of the dynamic foaming process of the samples, prepared using pure Al, and that with an additional Cf, under the same heating regime. It was found that the Cf, acting as an “artificial defect” in the matrix, effectively guided the cell’s nucleation process. It not only improved the dispersion of the cell nucleation—which led to a more dispersed distribution of internal stress in the early nucleation stage—but also effectively eliminated the influence of the internal differences caused by the preparation method, which led to a more uniform distribution of cells, during the nucleation and growth stage. Thus, the cell evolution stability was greatly improved when the matrix was still in the solid phase.

In the design of distributed MIMO-SAR systems, the optimization of the satellite spacing along track is an important prerequisite for achieving the task of high resolution and wide swath. From the perspective of system performance optimization, this paper takes the along-track distance between adjacent satellites and PRF is used as an optimization variable, while considering the change of the vertical track baseline, combining genetic algorithm and nonlinear programming to obtain a global optimal solution. A method of optimizing the satellite spacing along track based on improved genetic algorithm is proposed and verified by simulation the correctness of the optimization method. The indicators and methods given in this article are of great significance for guiding the structural design of formation satellite systems and improving the performance of high resolution and wide swath measurement of SAR along track.

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