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Purpose: This study aims to show the viability of conducting three‐dimensional (3D) myocardial perfusion quantification covering the entire heart using both GRE and bSSFP sequences with hyperpolarized HP001. Methods: A GRE sequence and a bSSFP sequence, both with a stack‐of‐spirals readout, were designed and applied to three pigs. The images were reconstructed using 13$$ {}^{13} $$C coil sensitivity maps measured in a phantom experiment. Perfusion was quantified using a constrained decomposition method, and the estimated rest/stress perfusion values from 13$$ {}^{13} $$C GRE/bSSFP and Dynamic contrast‐enhanced MRI (DCE‐MRI) were individually analyzed through histograms and the mean perfusion values were compared with reference values obtained from PET(15$$ {}^{15} $$O‐water). The Myocardial Perfusion Reserve Index (MPRI) was estimated for 13$$ {}^{13} $$C GRE/bSSFP and DCE‐MRI and compared with the reference values. Results: Perfusion values, estimated by both DCE and 13$$ {}^{13} $$C MRI, were found to be lower than reference values. However, DCE‐MRI's estimated perfusion values were closer to the reference values than those obtained from 13$$ {}^{13} $$C MRI. In the case of MPRI estimation, the 13$$ {}^{13} $$C estimated MPRI values (GRE/bSSFP: 2.3/2.0) more closely align with the literature value (around 3) than the DCE estimated MPRI value (1.6). Conclusion: This study demonstrated the feasibility of 3D whole‐heart myocardial perfusion quantification using hyperpolarized HP001 with both GRE and bSSFP sequences. The 13$$ {}^{13} $$C perfusion measurements underestimated perfusion values compared to the 15$$ {}^{15} $$O PET literature value, while the 13$$ {}^{13} $$C estimated MPRI value aligned better with the literature. This preliminary result indicates 13$$ {}^{13} $$C imaging may more accurately estimate MPRI values compared to DCE‐MRI. [ABSTRACT FROM AUTHOR]

In this study, the improvement effect of different organic substances on compacted cohesive soil in southern Xinjiang was discussed, with emphasis on the influence of different organic substances on soil chemical properties and microorganisms, so as to determine the best carbon source input and provide theoretical support for the rational utilization of organic materials in southern Xinjiang. Field experiments were conducted to evaluate the effects of farm fertilizer, biochar, commercial organic fertilizer, microbial fertilizer and mineral potassium humate on physical and chemical properties of viscous soil, agronomic properties and yield of cotton, with three gradients for each organic fertilizer. The results showed that: (1) all organic fertilizers improved soil structure, among which farm fertilizer significantly reduced soil bulk density and salinity, increased soil organic matter, total nitrogen and available nutrients, and thus increased cotton height, stem diameter and yield. The optimal application amount was 36000 kg/hm². (2) The application of different organic matter increased the contents of organic matter, total nitrogen, hydrolyzed nitrogen, available phosphorus and available potassium in 0-40 cm soil layer, increased the number of bacteria, fungi and actinomyces, and reduced soil salinity; (3) Structural equation model (SEM) was used to investigate the effect mechanism of organic matter input on soil microbial quantity, soil physicochemical properties and cotton yield. The model further confirmed the mechanism: the input of organic matter mainly regulates the number of microorganisms and the richness of microbial species, thereby improving the physical and chemical properties of soil and thereby increasing the cotton yield. The addition of 5 kinds of organic materials can promote the growth and yield of cotton. The comprehensive evaluation shows that the improvement effect is best when the fertilizer dosage is 150% of the recommended amount. In summary, as an effective soil amendment, farm manure can not only alleviate soil compaction, but also significantly improve the growth potential of cotton, which is in line with the goal of sustainable agricultural development. [ABSTRACT FROM AUTHOR]

The contradiction between increased irrigation demand and water scarcity in arid regions has become more acute for crops as a result of global climate change. This highlights the urgent need to improve crop water use efficiency. In this study, four irrigation volumes were established for drip-irrigated maize under plastic mulch: 2145 m3 ha−1 (W1), 2685 m3 ha−1 (W2), 3360 m3 ha−1 (W3), and 4200 m3 ha−1 (W4). The effects of these volumes on soil moisture, maize growth, water consumption, crop coefficients, and yield were analyzed. The results showed that increasing the irrigation volume led to a 2.86% to 8.71% increase in soil moisture content, a 24.56% to 47.41% increase in water consumption, and a 3.43% to 35% increase in the crop coefficient. Maize plant height increased by 16.34% to 42.38%, ear height by 16.85% to 51.01%, ear length by 2.43% to 28.13%, and yield by 16.96% to 39.24%. Additionally, soil temperature was reduced by 1.67% to 5.67%, and the maize bald tip length decreased by 6.62% to 48%. The irrigation water use efficiency improved by 6.57% to 28.89%. A comprehensive evaluation using the TOPSIS method demonstrated that 3360 m3 ha−1 of irrigation water was an effective irrigation strategy for increasing maize yield under drip irrigation with plastic mulch in the southern border area. Compared to 4200 m3 ha−1, this strategy saved 840 m3 ha−1 of irrigation water, increased the irrigation water use efficiency by 23.96%, and resulted in only a 0.84% decrease in yield. The findings of this study provide a theoretical foundation for optimizing production benefits in the context of limited water resources. [ABSTRACT FROM AUTHOR]

This study aimed to explore the combined effects of micro-nano bubble water drip irrigation and different phosphorus (P) application rates (P0: 0 kg·hm−2; P1: 86 kg·hm−2; P2: 172 kg·hm−2; P3: 258 kg·hm−2) on maize growth, soil phosphorus dynamics, and phosphorus use efficiency to optimize irrigation and P fertilizer use efficiency. Through a field column experiment, the impact of micro-nano bubble water drip irrigation on maize plant height, stem diameter, leaf SPAD values, biomass, and yield was evaluated. The results showed that (1) irrigation methods significantly affected maize growth indicators such as plant height, stem diameter, and root dry weight. Micro-nano bubble water drip irrigation consistently promoted growth during all growth stages, especially under higher P application. (2) P application significantly increased the dry weight and P concentration in maize roots, stems, leaves, ears, and grains. Under micro-nano bubble water drip irrigation, the P concentrations in roots and grains increased by 59.28% to 92.59%. (3) Micro-nano bubble water drip irrigation significantly enhanced P uptake efficiency, partial factor productivity of P, and agronomic P use efficiency. Particularly under P1 and P2 treatments, the increases were 134.91% and 45.42%, respectively. Although the effect on apparent P recovery efficiency was relatively small, micro-nano bubble water drip irrigation still improved P utilization under moderate P levels. (4) Structural equation modeling indicated that P supply under micro-nano bubble water drip irrigation primarily regulated alkaline protease and alkaline phosphatase, enhancing soil P availability, which in turn promoted maize P accumulation and increased yield. In conclusion, this study demonstrated that the combination of micro-nano bubble water drip irrigation and appropriate P application can effectively promote maize growth and nutrient utilization, providing a theoretical basis for optimizing irrigation and fertilization strategies in maize production. [ABSTRACT FROM AUTHOR]

Defect engineering is a key chemical tool to modulate the electronic structure and reactivity of nanostructured catalysts. Here, it is reported how targeted introduction of defect sites in a 2D palladium metallene nanostructure results in a highly active catalyst for the alkaline oxygen reduction reaction (ORR). A defect‐rich WOx and MoOx modified Pd metallene (denoted: D‐Pd M) is synthesized by a facile and scalable approach. Detailed structural analyses reveal the presence of three distinct atomic‐level defects, that are pores, concave surfaces, and surface‐anchored individual WOx and MoOx sites. Mechanistic studies reveal that these defects result in excellent catalytic ORR activity (half‐wave potential 0.93 V vs. RHE, mass activity 1.3 A mgPd−1 at 0.9 V vs. RHE), outperforming the commercial references Pt/C and Pd/C by factors of ≈7 and ≈4, respectively. The practical usage of the compound is demonstrated by integration into a custom‐built Zn‐air battery. At low D‐Pd M loading (26 µgPd cm−2), the system achieves high specific capacity (809 mAh gZn−1) and shows excellent discharge potential stability. This study therefore provides a blueprint for the molecular design of defect sites in 2D metallene nanostructures for advanced energy technology applications. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrate reduction is a promising approach to remove harmful nitrate and produce ammonia in aqueous media. Here, we demonstrate how 3D printed polymer electrodes can be electroless plated with a bimetallic NiCu alloy film suitable for sustained nitrate‐to‐ammonia reduction. Characterization by powder X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning/transmission electron microscopy and energy‐dispersive X‐ray spectroscopy indicate that the electrode has a two‐layer structure consisting of polymer/ coating layer of metal alloys. The composite electrode shows high‐performance in the nitrate‐to‐ammonia electroreduction, giving NH3 Faradaic efficiencies of up to 83 % and NH3 yield rates up to 860 μg/(h cm2) at −0.38 V vs. RHE. We show that the electrode can easily be integrated into a Zn‐nitrate battery, giving a power density of 3.8 mW cm−2 with continuous NH3 production. The system combines three productive outputs, that is removal of nitrate pollutants, synthesis of valuable ammonia and generation of "green" electricity. [ABSTRACT FROM AUTHOR]