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The homeodomain-leucine zipper (HD-ZIP) transcription factors, representing one of the largest plant-specific superfamilies, play important roles in the response to various abiotic stresses. However, the functional roles of HD-ZIPs in abiotic stress tolerance and the underlying mechanisms remain relatively limited in Miscanthus sinensis. In this study, we isolated an HD-ZIP TF gene, MsHDZ23, from Miscanthus and ectopically expressed it in Arabidopsis. Transcriptome and promoter analyses revealed that MsHDZ23 responded to salt, alkali, and drought treatments. The overexpression (OE) of MsHDZ23 in Arabidopsis conferred higher tolerance to salt and alkali stresses compared to wild-type (WT) plants. Moreover, MsHDZ23 was able to restore the hb7 mutant, the ortholog of MsHDZ23 in Arabidopsis, to the WT phenotype. Furthermore, MsHDZ23-OE lines exhibited significantly enhanced drought stress tolerance, as evidenced by higher survival rates and lower water loss rates compared to WT. The improved drought tolerance may be attributed to the significantly smaller stomatal aperture in MsHDZ23-OE lines compared to WT. Furthermore, the accumulation of the malondialdehyde (MDA) under abiotic stresses was significantly decreased, accompanied by dramatically enhanced activities in several antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in the transgenic plants. Collectively, these results demonstrate that MsHDZ23 functions as a multifunctional transcription factor in enhancing plant resistance to abiotic stresses.

Exsolution, as an effective approach to constructing particle-decorated interfaces, is still challenging to yield interfacial films rather than isolated particles. Inspired by in vivo near-infrared laser photothermal therapy, using 3 mol% Y _2 O _3 stabilized tetragonal zirconia polycrystals (3Y-TZP) as host oxide matrix and iron-oxide (Fe _3 O _4 / γ -Fe _2 O _3 / α -Fe _2 O _3 ) materials as photothermal modulator and exsolution resource, femtosecond laser ultrafast exsolution approach is presented enabling to conquer this challenge. The key is to trigger photothermal annealing behavior via femtosecond laser ablation to initialize phase transition from monoclinic zirconia (m-ZrO _2 ) to tetragonal zirconia (t-ZrO _2 ) and induce t-ZrO _2 columnar crystal growth. Fe-ions rapidly segregate along grain boundaries and diffuse towards the outmost surface, and become ‘frozen’, highlighting the potential to use photothermal materials and ultrafast heating/quenching behaviors of femtosecond laser ablation for interfacial exsolution. Triggering interfacial iron-oxide coloring exsolution is composition and concentration dependent. Photothermal materials themselves and corresponding photothermal transition capacity play a crucial role, initializing at 2 wt%, 3 wt%, and 5 wt% for Fe _3 O _4 / γ -Fe _2 O _3 / α -Fe _2 O _3 doped 3Y-TZP samples. Due to different photothermal effects, exsolution states of ablated 5 wt% Fe _3 O _4 / γ -Fe _2 O _3 / α -Fe _2 O _3 -doped 3Y-TZP samples are totally different, with whole coverage, exhaustion (ablated away) and partial exsolution (rich in the grain boundaries in subsurface), respectively. Femtosecond laser ultrafast photothermal exsolution is uniquely featured by up to now the deepest microscale (10 μ m from 5 wt%-Fe _3 O _4 -3Y-TZP sample) Fe-elemental deficient layer for exsolution and the whole coverage of exsolved materials rather than the formation of isolated exsolved particles by other methods. It is believed that this novel exsolution method may pave a good way to modulate interfacial properties for extensive applications in the fields of biology, optics/photonics, energy, catalysis, environment, etc.

Hydrological model is an important tool for flood simulation, and most of the models contain a certain number of parameters. There? fore, parameter calibration is one of the keys to improve the precision of hydrological model runoff simulation and ensure the accuracy of mod? el results. As the optimization standard of parameter calibration process, there is currently no detailed classification system to provide a clear selection basis for the selection of objective function. In order to explore the effects of different types of objective functions on the calibration results of hydrological model parameters and the precision of runoff simulation, this paper comprehensively considered various types of objectives, such as Nash efficiency coefficient, Kling-Gupta coefficient, flood relative error, etc., and constructed an objective function classification system that includes high flow target, low flow target, flood volume target, flood process target and weighted target. According to the requirements of the current hydrological forecast information standard, some criteria were provided for the selection of objective function. Further, the Xinanjiang model was established, and the optimization algorithms of SCE-UA and NSGA-II were introduced. A variety of objective function selection schemes were set up for different algorithms, and the influence of different objective function schemes and optimization algorithms on the precision of runoff simulation was analyzed by taking Muma River in Hanjiang River basin as an example. The results show that using a single objective function can improve the simulation accuracy of hydrological elements embodied by the objective function; Selecting the appropriate objective function is the key to improve the precision of runoff simulation. Under the requirements of existing norms, selecting flood process target and high flow target is the best choice to ensure the accuracy of hydrological model. Compared with Nash efficiency coefficient, Kling Gupta coefficient has better performance in flood volume simulation accuracy and is a better choice for flood process target. The simulation results of weighted single target method and multi-target method are different in the high-flow part. [ABSTRACT FROM AUTHOR]

A generalization of the famous Caccetta–Häggkvist conjecture, suggested by Aharoni, is that any family F =(F 1 , … , F n ) ${\rm{ {\mathcal F} }}=({F}_{1},\ldots ,{F}_{n})$ of sets of edges in K n ${K}_{n}$, each of size k $k$, has a rainbow cycle of length at most ⌈ n k ⌉ $\lceil \frac{n}{k}\rceil $. In works by the author with Aharoni and by the author with Aharoni, Berger, Chudnovsky, and Zerbib, it was shown that asymptotically this can be improved to O(log n ) $O(\mathrm{log}n)$ if all sets are matchings of size 2, or all are triangles. We show that the same is true in the mixed case, that is, if each F i ${F}_{i}$ is either a matching of size 2 or a triangle. We also study the case that each F i ${F}_{i}$ is a matching of size 2 or a single edge, or each F i ${F}_{i}$ is a triangle or a single edge, and in each of these cases we determine the threshold proportion between the types, beyond which the rainbow girth goes from linear to logarithmic. [ABSTRACT FROM AUTHOR]

The von Hippel-Lindau tumor suppressor protein (VHL), an E3 ubiquitin ligase, functions as a critical regulator of the oxygen-sensing pathway for targeting hypoxia-inducible factors. Recent evidence suggests that mammalian VHL may also be critical to the NF-κB signaling pathway, although the specific molecular mechanisms remain unclear. Herein, the roles of mandarin fish (Siniperca chuatsi) VHL (scVHL) in the NF-κB signaling pathway and mandarin fish ranavirus (MRV) replication were explored. The transcription of scVHL was induced by immune stimulation and MRV infection, indicating a potential role in innate immunity. Dual-luciferase reporter gene assays and reverse transcription quantitative PCR (RT-qPCR) results demonstrated that scVHL evoked and positively regulated the NF-κB signaling pathway. Treatment with NF-κB signaling pathway inhibitors indicated that the role of scVHL may be mediated through scIKKα, scIKKβ, scIκBα, or scp65. Co-immunoprecipitation (Co-IP) analysis identified scIκBα as a novel target protein of scVHL. Moreover, scVHL targeted scIκBα to catalyze the formation of K63-linked polyubiquitin chains to activate the NF-κB signaling pathway. Following MRV infection, NF-κB signaling remained activated, which, in turn, promoted MRV replication. These findings suggest that scVHL not only positively regulates NF-κB but also significantly enhances MRV replication. This study reveals a novel function of scVHL in NF-κB signaling and viral infection in fish. [ABSTRACT FROM AUTHOR]