Optimization of Mg-Al Layered Double Hydroxide Film Preparation and Corrosion Resistance Study on AZ91D Mg Alloy by Multivariate Polynomial Regression Fitting.

Layered double hydroxide (LDH) films have received extensive attention for their unique physical barrier function and ion exchange properties, which make them promising candidates for corrosion protection of magnesium alloys. In this paper, we used the multiple polynomial regression fitting method to establish a regression equation for the electrochemical corrosion resistance with the reaction temperature (T), pH, and reaction time (t) of the Mg-Al LDH film on the AZ91D magnesium alloy. The goodness of fit, confidence, and residual analyses confirmed the high accuracy of the model equation. According to the calculation using the fmincon function, the best corrosion resistance of the prepared samples could be achieved when the parameters are T = 135 °C, pH = 12.0, and t = 15 h. Then, the experimental results showed that the corrosion current density (Icorr) of the obtained LDH film under the above conditions could be 1.07 × 10-7 A/cm2, approximately 3 orders of magnitude lower than the magnesium alloy substrate, after immersion in a 3.5 wt % NaCl solution for 180 h, the surface structure of the LDH film did not change significantly, and the Icorr was still 2 orders of magnitude higher than that of the magnesium alloy substrate. Hence, a synergistic effect equation for the reaction temperature, pH, and reaction time on the corrosion resistance of the LDH film on a magnesium alloy surface prepared by the hydrothermal method was obtained. Moreover, using this equation, we obtained an LDH film with good corrosion resistance and durability, providing theoretical guidance for optimizing the process of preparing the LDH film by the hydrothermal method in practical applications.

Validation of the Chinese version of the coping strategies for victims of cyberbullying scale.

BACKGROUND: Although abundant evidence has confirmed cyberbullying as a global online risk, little is known about the coping strategies employed by victims and those who experiencing bullying. A validated scale for coping with cyberbullying could inform evidence-based social services and enable comparative studies of this phenomenon among victims from different backgrounds. This study aims to validate the Coping Strategies for Victims of Cyberbullying (CSVC) scale among Chinese adolescents and to compare its effectiveness between victims and bully-victims (individuals with dual roles). METHODS: A 25-item CSVC scale was translated and adapted for cultural relevance in the Chinese context. A sample of 1,716 adolescents, aged 13-18 years, from two middle schools and one high school in China, was recruited. Both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted. RESULTS: The EFA revealed that the Chinese version of the CSVC scale had satisfactory validity. The CFA demonstrated a good fit for the eight-factor model in assessing different coping strategies for cyberbullying. Differences in the selection of coping strategies were observed between the general adolescent population and sexual and gender minorities. CONCLUSIONS: Future intervention studies may use this validated scale to educate adolescents, both those affected by cyberbullying and those who are not, to learn a broader range of coping strategies and to choose more effective ones.

Inoculum Sources of Puccinia striiformis f. sp. tritici for Stripe Rust Epidemics on the Eastern Coast of China.

Stripe rust, a fungal disease caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases affecting wheat production areas worldwide. In recent years in China, wheat stripe rust has caused huge yield losses throughout the vast Huang-Huai-Hai region, including the eastern coast regions, especially Shandong province. The aim of the present study was to explore the population structure and potential inoculum sources of the pathogen in this region. A total of 234 Pst isolates in 2021 were collected and isolated from seven provinces and identified for virulence phenotypes using 19 Chinese differentials and for genotypes using 17 single-nucleotide polymorphism-based Kompetitive allele-specific PCR markers. The virulence phenotype tests identified predominant races CYR34 (18.0%) and CYR32 (16.0%) in Shandong, which were similar to the results in Henan province, also with the predominant races CYR34 (21.9%) and CYR32 (18.8%). Based on the virulence data of phenotyping, the Pst populations in Shandong, Hubei, and Henan were similar. The genotypic analysis revealed remarkable gene flows among the Shandong, Hubei, Henan, Yunnan, and Guizhou populations, showing a migration of Pst from the southwestern oversummering regions to Shandong through the winter spore production regions. Genetic structure analysis also indicated an additional migration route from the northwestern oversummering regions through winter spore production regions to Shandong. The results are useful for understanding stripe rust epidemiology in the eastern coast region and improving control of the disease throughout the country.

Sensitivity of Puccinia triticina f. sp. tritici from China to Triadimefon and Resistance Risk Assessment.

Wheat leaf rust, caused by Puccinia triticina f. sp. tritici (Pt), is distributed widely in wheat-producing areas and results in serious yield losses worldwide. In China, leaf rust has been largely controlled with a demethylation inhibitor (DMI) fungicide, triadimefon. Although high levels of fungicide resistance in pathogens have been reported, no field failure of wheat leaf rust to DMI fungicides has been reported in China. A resistance risk assessment of triadimefon to Pt was investigated in the present study. The sensitivity of 197 Pt isolates across the country to triadimefon was determined, and the density distribution of EC50 values (concentration at which mycelial growth is inhibited by 50%) showed a continuous multimodal curve because of the extensive use of this fungicide in wheat production, with a mean value of 0.46 µg/ml. The majority of the tested Pt isolates were sensitive to triadimefon, whereas 10.2% developed varying degrees of resistance. Characterization of parasitic fitness revealed that the triadimefon-resistant isolates exhibited strong adaptive traits in urediniospore germination rate, latent period, sporulation intensity, and lesion expansion rate. No correlation was observed between triadimefon and tebuconazole and hexaconazole, which have the similar mode of action, or pyraclostrobin and flubeneteram, which have different modes of action. Overexpression of the target gene Cyp51 led to the triadimefon resistance of Pt. The risk of resistance to triadimefon in Pt may be low to moderate. This study provided important data for fungicide resistance risk management against wheat leaf rust.

Effects of Flubeneteram on Inhibiting the Development of Puccinia striiformis f. sp. tritici in Wheat Leaves.

Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is a serious threat to wheat production, and the application of fungicides is one of the most important means for controlling the disease. The purpose of this study is to determine the effects of a new succinate dehydrogenase inhibitor (SDHI) fungicide, flubeneteram, on reducing stripe rust. The baseline sensitivity of 173 Pst isolates from 13 provinces of China to flubeneteram was determined. Flubeneteram displayed significant effects on inhibiting SDH enzymes of Pst. Histological observations showed that after flubeneteram application, the formation and development of Pst hyphae and haustoria were significantly inhibited, and the structures were destroyed. Flubeneteram primed wheat for salicylic acid-induced defenses via upregulating pathogenesis-related genes (PR1 and PR2). Altogether, our study is the first to provide evidence that flubeneteram induces wheat defense against Pst infection. The findings indicate that flubeneteram could be an effective fungicide for managing stripe rust.

Environmental non-governmental organizations and air-pollution governance: Empirical evidence from OECD countries.

Based on the panel data of environmental Non-Governmental Organizations (ENGOs) and air pollution in OECD countries, this paper uses econometric model to investigate the governance effect of ENGOs on air pollution. The results show that: ENGOs have a positive impact on the improvement of environmental quality, and the results are still valid after a series of robustness tests; Further mechanism analysis found that the environmental improvement by ENGOs is mainly achieved by increasing investment in environmental protection. This study provides empirical evidence for the effect of ENGOs on air pollution, and further provides ideas for environmental governance.

Laser-Induced Patterned Photonic Crystal Heterostructure for Multimetal Ion Recognition.

In this work, a new method of direct laser writing patterned photonic crystal heterostructure on a glass surface is proposed. A multi-heterostructure photonic crystal (MHPC) is predeposited on the glass surface and then the laser spot is focused on it and moves according to the set program, leading to the formation of patterned MHPC. Scanning electron microscopy (SEM) and finite element simulation show that the patterning is caused by the local thermal annealing of the polymer colloidal spheres through the thermal conduction effect of the substrate on the laser energy. The patterned area presents a function of the water confinement effect and can be used as a high-performance droplet analysis chip. By integrating the patterned MHPC array and seven fluorescent dyes, nine metal ions can be successfully recognized and discriminated. This approach is quite facile and fast for designing colloidal photonic crystals with controllable patterns. Moreover, it is of considerable significance for the practical application of photonic crystal heterostructure in the detection, sensing, anti-counterfeiting, and display fields.

Fluorescent Fluid in 3D-Printed Microreactors for the Acceleration of Photocatalytic Reactions.

The photochemical microreactor has been a burgeoning field with important application in promoting photocatalytic reactions. The integration of light-converting media and microflow chemistry renders new opportunity for efficient utilization of light and high conversion rate. However, the flexibility of emission light wavelength regulation and the universality of the microreactor remain significant problems to be solved. Here, a photochemical microreactor filled with fluorescent fluid is fabricated by a 3D printing technique. The light-converting medium in the fluorescent fluid is used to collect and convert light, and then delivers light energy to the embedded continuous-flow reaction channels to promote the chemical reaction process. With the merits of flowability, different light-converting media can be replaced, making it a general tool for photocatalytic reactions in rapid screening, parameters optimization, and kinetic mechanism research.

A general strategy to fabricate photonic crystal heterostructure with Programmed photonic stopband.

In this paper, we present a general fabrication strategy to achieve the structure control and the flexible photonic stop band regulation of (2+1) D photonic crystal heterostructures (PCHs) by layer-by-layer depositing the annealed colloidal crystal monolayers of different sphere size. The optical properties of the resulting (2+1) DPCHs with different lattice constants were systematically studied and a universal photonic stopband variation rule was proposed, which makes it possible to program any kind of stopband structure as required, such as dual- or multi-stopbands PCH and ultra-wide stopband PCH. Furthermore, PCH with dual-stopbands overlapping the excitation wavelength (E) and emission wavelength(F) of Ru complex was fabricated by finely manipulating the spheres' diameter of colloidal monolayers. And an additional 2-fold fluorescence enhancement in comparison to that on the single stopband sample was achieved. This strategy affords new opportunities for delicate engineering the photonic behaviour of PCH, and also is of great significance for the practical application based on their bandgap property.