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Aluminide coatings have become an important thermal protection coating for the hot-end components of gas turbines.This is due to its ability to form an Al2O3 film when in high-temperature service，which effectively improves the components’resistance to high-temperature oxidation and thermal corrosion，thereby prolonging their service life.However，the phase transition of the aluminum-rich β-NiAl phase to the aluminum-poor γ-Ni3Al phase of the single aluminide coating is prone to occur during service，which reduces the Al content in the coating and makes it difficult for the coating to continuously form a dense Al2O3 film.In this paper，the use of element modification (such as Si，Cr，Co，Pt，Pd，and rare earth elements) to improve the high-temperature oxidation and thermal corrosion performance of aluminide coatings was summarized.Among these，the Pt element was found to simultaneously promote the oxidation of the Al element into dense Al2O3 film and improve the anti-peeling ability of the oxide film，thus having the best modification effect on the high-temperature performance of the aluminide coating.Based on the effect of single-element modification，the researchers developed multiple elements (binary and ternary) co-modified aluminide coatings.The performance of aluminide coatings could be improved more effectively by the co-modification of Pt and elements that hindered the diffusion of elements between the coating and the substrate or inhibited phase change elements.Finally，the future development trend of modified aluminide coatings might have been higher co-modification (quaternary and pentagonal) of Pt with rare earth or other elements.

Nitrogen (N), phosphorus (P) and potassium (K) are important essential nutrients for plant growth and development, but their functions in energy status remains unclear. Here, we grew Nipponbare rice seedlings in a growth chamber for 20 d at 30 °C/24 °C (day/night) under natural sunlight conditions with different nutrient regimes. The results showed that N had the strongest influence on the plant growth and development, followed by P and K. The highest nonstructural carbohydrate content, dry matter weight, net photosynthetic rate (Pn), ATP content, as well as NADH dehydrogenase, cytochrome oxidase and ATPase activities were found in the plants that received sufficient N, P and K. The lowest values of these parameters were detected in the N-deficient plants. Higher dry matter accumulation was observed in the K-deficient than in the P-deficient treatments, but there was no significant difference in the ratio of respiration rate to Pn between these two treatments, suggesting that differences in energy production efficiency may have accounted for this result. This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase, cytochrome oxidase and ATPase in the K-deficient plants than in the P-deficient plants. We therefore inferred different abilities in energy production efficiency among N, P and K in rice seedlings, which determined rice plant growth and development.

Straw return has important impacts on black soil protection, food security, and environmental protection. One year of straw return (S1) reduces rice yield and increases greenhouse gas (GHG) emissions. However, the effects of successive years of straw return on rice yield, soil nutrients, and GHG emissions in the northeast rice region are still unclear. Therefore, we conducted four successive years of straw return (S4) in a positional experiment to investigate the effects of different years of straw return on rice yield, soil nutrients, and GHG emissions in the northeast rice region. The experimental treatments included the following: no straw return (S0), a year of straw return (S1), two successive years of straw return (S2), three successive years of straw return (S3), and four successive years of straw return (S4). Compared with S1, the rice yields of S2, S3, and S4 increased by 10.89%, 15.46%, and 16.98%, respectively. But only S4 increased by 4.64% compared to S0, while other treatments were lower than S0. S4 increased panicles per m2 and spikelets per panicle by 9.34% and 8.93%, respectively, compared to S1. Panicles per m2 decreased by 8.06% at S4 compared to S0, while spikelets per panicle increased by 13.23%. Compared with S0, the soil organic carbon, total nitrogen, NH4+-N, NO3−-N, available phosphorus, and available potassium of S4 increased by 11.68%, 10.15%, 24.62%, 21.38%, 12.33%, and 13.35%, respectively. Successive years of rice straw return decreased GHG intensity (GHGI). Compared with S1, the GHGI of S4, S3, and S2 decreased by 16.2%, 11.84%, and 9.36%, respectively. Thus, S4 increased rice yield and soil nutrients, reducing GHGI. [ABSTRACT FROM AUTHOR]

Soil potassium deficiency is a common issue limiting agricultural productivity. Potassium-solubilizing bacteria (KSB) show significant potential in mitigating soil potassium deficiency, improving soil quality, and enhancing plant growth. However, different KSB strains exhibit diverse solubilization mechanisms, environmental adaptability, and growth-promoting abilities. In this study, we isolated a multifunctional KSB strain ZHS-1, which also has phosphate-solubilizing and IAA-producing capabilities. 16S rDNA sequencing identified it as Pantoea vagans. Scanning electron microscopy (SEM) showed that strain ZHS-1 severely corroded the smooth, compact surface of potassium feldspar into a rough and loose state. The potassium solubilization reached 20.3 mg/L under conditions where maltose was the carbon source, sodium nitrate was the nitrogen source, and the pH was 7. Organic acid metabolism profiling revealed that strain ZHS-1 primarily utilized the EMP-TCA cycle, supplemented by pathways involving pantothenic acid, glyoxylic acid, and dicarboxylic acids, to produce large amounts of organic acids and energy. This solubilization was achieved through direct solubilization mechanisms. The strain also secreted IAA through a tryptophan-dependent metabolic pathway. When strain ZHS-1 was inoculated into the rhizosphere of rice, it demonstrated significant growth-promoting effects. The rice plants exhibited improved growth and root development, with increased accumulation of potassium and phosphorus. The levels of available phosphorus and potassium in the rhizosphere soil also increased significantly. Additionally, we observed a decrease in the relative abundance of Actinobacteria and Proteobacteria in the rice rhizosphere soil, while the relative abundance of genera associated with acid production and potassium solubilization, such as Gemmatimonadota, Acidobacteria, and Chloroflexi, as well as Cyanobacteria, which are beneficial to plant growth, increased. These findings contribute to a deeper understanding of the potassium solubilization mechanisms of strain ZHS-1 and highlight its potential as a plant growth-promoting rhizobacteria. [ABSTRACT FROM AUTHOR]

Rice straw is an agricultural waste, the disposal of which through open burning is an emerging challenge for ecology. Green manufacturing using straw returning provides a more avant-garde technique that is not only an effective management measure to improve soil fertility in agricultural ecosystems but also nurtures environmental stewardship by reducing waste and the carbon footprint. However, fresh straw that is returned to the field cannot be quickly decomposed, and screening microorganisms with the capacity to degrade straw and understanding their mechanism of action is an efficient approach to solve such problems. This study aimed to reveal the potential mechanism of influence exerted by exogenous degradative bacteria (ZJW-6) on the degradation of straw, growth of plants, and soil bacterial community during the process of returning rice straw to the soil. The inoculation with ZJW-6 enhanced the driving force of cellulose degradation. The acceleration of the rate of decomposition of straw releases nutrients that are easily absorbed by rice (Oryza sativa L.), providing favorable conditions for its growth and promoting its growth and development; prolongs the photosynthetic functioning period of leaves; and lays the material foundation for high yields of rice. ZJW-6 not only directly participates in cellulose degradation as degrading bacteria but also induces positive interactions between bacteria and fungi and enriches the microbial taxa that were related to straw degradation, enhancing the rate of rice straw degradation. Taken together, ZJW-6 has important biological potential and should be further studied, which will provide new insights and strategies for the appropriate treatment of rice straw. In the future, this degrading bacteria may provide a better opportunity to manage straw in an ecofriendly manner. [ABSTRACT FROM AUTHOR]

【Background】Maize production in Jilin province of China needs irrigation because precipitation and antecedent soil water in its growth season cannot meet its demand. Although the impact of water stress in maize growth has been well documented, how its physiological characteristics respond to irrigation amount is an issue remaining obscure for maize production in Jilin province. 【Objective】This paper aims to elucidate irrigation-water use efficiency of the maize under different irrigation amounts, with a view to improve water use efficiency without compromising yield in the semi-arid areas in the west of the province. 【Method】A two-year field experiment was conducted with the variety Huanong 887 as the model plant. We compared four irrigation amounts: 500 (CK), 900 (Q1), 1 700 (Q2) and 2 500 m3/hm2 (Q3), and in each treatment we measured the accumulation of nitrogen, grain filling, activities of nitrogen metabolizing enzymes in leaves, as well as root injury level. 【Result】①The average grain-filling rate, 100-grain weight and root injury level all increased with the irrigation amount, but their values in Q2 and Q3 were significantly higher than those in Q1 and CK. ②Compared to Q1 and CK, Q2 and Q3 significantly increased nitrogen content in grains, stems and leaves. ③With the increase in irrigation amount, the activities of glutamine synthetase (GS) in the leaves increased, while the activities of glutamate dehydrogenase (GDH) in the leaves decreased. ④The yield increased with irrigation amount, especially in Q2 and Q3. ⑤No significant difference in yield and physiological traits was found between Q2 and Q3. 【Conclusion】Soil moisture is an important factor limiting growth and development of maize in the semi-arid areas in the western Jilin province. With the increase in irrigation amount, the yield, average grain-filling rate, 100-grain weight, root injury level, nitrogen accumulation and GS activity in the leaves all increased, while the activity of GDH in the leaves decreased. The physiological traits were significantly correlated with the yield. When the irrigation amount was 1 700 m3/hm2, the grain-filling rate, root injury level, nitrogen accumulation, nitrogen metabolizing enzyme activity in the leaves were optimal, giving the highest yield. It thus can be used as the reference irrigation strategy for maize production for the studied areas.

In this paper, we present a novel coordinated method tailored to address the dynamic multi-target hunting control problem in multi-agent systems, offering significant practical value. Our approach encompasses several key components: initially, we introduce a task allocation model that integrates a fuzzy inference system with a particle swarm optimization algorithm. This hybrid model efficiently allocates hunting tasks for scattered evading targets, effectively transforming the dynamic multi-target hunting problem into multiple dynamic single-target-hunting problems. This transformation enhances the speed and efficacy of task allocation. Subsequently, we propose an attraction/repulsive model grounded in potential field theory. This model facilitates the coordinated hunting of each target by organizing agents into subgroups. Relying solely on relative position and velocity information between agents and targets, our model simplifies computation, while maintaining effectiveness. Furthermore, the coordination of hunting activities for each target is achieved through a series of agent subgroups, guided by our proposed motion model. This systematic approach ensures a cohesive and efficient hunting strategy. Finally, we validate the effectiveness and feasibility of our proposed method through simulation results. These results provide empirical evidence of the method's efficacy and potential applicability in real-world scenarios. [ABSTRACT FROM AUTHOR]

Ascorbic acid (AsA) plays a crucial role in the physiological processes of rice plants when they encounter various biotic and abiotic stresses. However, the specific mechanism by which AsA affects cold tolerance in rice seedlings remains unclear. Two rice genotypes, Zhongzao39 (ZZ39) and its recombinant inbred line RIL82, were exposed to cold stress, resulting in more damage observed in RIL82 compared to ZZ39. This damage included higher levels of relative electrolytic leakage (REC), malondialdehyde (MDA), H2O2, a lower Fv/Fm, and a lower survival rate. A comprehensive analysis of transcriptome and metabolome data indicated that AsA was involved in regulating cold tolerance in ZZ39 and RIL82 seedling plants. AsA content increased in ZZ39 while it decreased in RIL82 under cold stress. Additionally, analysis of carbohydrate contents highlighted their important role in the responses to cold stress of these two genotypes. Importantly, exogenous AsA and sucrose, either alone or in combination, enhanced the values of maximum fluorescence quantum yield (Fv/Fm) and effective quantum yield (YII) as well as decreased H2O2 and MDA levels to improve cold tolerance in both genotypes compared with plants treated with H2O. These findings highlight the potential significance of AsA in mitigating the effects of cold stress on rice seedling plants. [ABSTRACT FROM AUTHOR]

BACKGROUND: Dry cultivation of rice is a water‐saving, emission reduction and labor‐saving rice farming method. However, the development of rice under dry cultivation is hampered by the limitations of dry cultivation on rice yield and rice quality. We hypothesized that additional silicon (Si) would be a measure to address these limitations or challenges. RESULTS: In the present study, we set up field trials with three treatments: flooded cultivation (W), dry cultivation (D) and dry cultivation plus Si. Yield and quality were reduced under D treatment compared to W treatment. The addition of Si promoted root development, increased plant height and leaf area, increased photosynthetic enzyme activity, net photosynthetic rate and SPAD values, and increased biomass under dry crop conditions. Under the drought conditions, silica up‐regulated the expression of AGPSI, SBEI, SBEIIb, SSI and SSII‐1 genes and the activities of ADP‐glucose pyrophosphorylase (AGPase), soluble starch synthetase (SSS) and starch branching enzyme (SBE) enzymes, which reduced protein, amylose, chalkiness percentage and chalkiness degree, increased brown rice rate, milled rice rate and head milled rice rate, and also improved rice quality. In addition, the increase of AGPase, SSS and SBE enzyme activities promoted the filling rate and the number of spikes was guaranteed, whereas the yield was improved by promoting the seed setting rate and 1000‐grain weight. CONCLUSION: The results of the present study indicate that adding appropriate amounts of Si fertilizer can improve the yield and quality of rice under dry cultivation by regulating source supply capacity and grain starch synthesis. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Many SARS-CoV-2 neutralizing antibodies (nAbs) lose potency against variants of concern. In this study, we developed 2 strategies to produce mutation-resistant antibodies. First, a yeast library expressing mutant receptor binding domains (RBDs) of the spike protein was utilized to screen for potent nAbs that are least susceptible to viral escape. Among the candidate antibodies, P5-22 displayed ultrahigh potency for virus neutralization as well as an outstanding mutation resistance profile. Additionally, P14-44 and P15-16 were recognized as mutation-resistant antibodies with broad betacoronavirus neutralization properties. P15-16 has only 1 binding hotspot, which is K378 in the RBD of SARS-CoV-2. The crystal structure of the P5-22, P14-44, and RBD ternary complex clarified the unique mechanisms that underlie the excellent mutation resistance profiles of these antibodies. Secondly, polymeric IgG enhanced antibody avidity by eliminating P5-22's only hotspot, residue F486 in the RBD, thereby potently blocking cell entry by mutant viruses. Structural and functional analyses of antibodies screened using both potency assays and the yeast RBD library revealed rare, ultrapotent, mutation-resistant nAbs against SARS-CoV-2., Introduction Neutralizing antibodies (nAbs), which show efficacy for prophylactic as well as therapeutic use, are being developed against the spike (S) protein of SARS-CoV-2 (1-8). These nAbs have shown efficacy [...]