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The effects of rootstocks tomato (Solanum lycopersicum L.), eggplant (Solanum melongena L.), and nightshade (Solanum nigrum L.) grafting on the growth and selenium (Se) accumulation of Cyphomandra betacea Sendt. seedlings were studied to identify the most suitable rootstock for increasing Se uptake of fruit trees grown in Se-contaminated soil. The rootstocks of tomato, eggplant, and nightshade grafting increased the scion biomass of C. betacea seedlings by 146.1%, 23.2%, and 94.5%, respectively, compared with the un-grafted seedlings. Moreover, tomato, eggplant, and nightshade rootstocks grafting increased the photosynthesis, superoxide dismutase activity, and peroxidase activity, while reducing the catalase activity and soluble protein content of C. betacea seedlings. Although all three rootstocks grafting decreased Se contents in rootstock roots and stems, only nightshade rootstock grafting increased Se content in the scions of C. betacea seedlings. Notably, root biomass, catalase activity, soluble protein content, rootstock root Se content, and rootstock stem Se content were closely related to the scion Se content. These findings suggest that only grafting onto nightshade rootstock significantly enhances Se uptake in C. betacea, whereas tomato and eggplant rootstocks grafting have no effect on Se uptake. NOVELTY STATEMENT: This study shows that under selenium (Se)-contaminated soil conditions, tomato, eggplant, and nightshade rootstocks can promote the growth of C. betacea seedlings and improve their stress resistance. The nightshade rootstock stands out for its ability to promote Se uptake in C. betacea seedlings, suggesting its suitability as a promising rootstock to enhance both growth and Se uptake in C. betacea. [ABSTRACT FROM AUTHOR]

Both the nacre‐like bionic microstructure and the spiral laminated bionic configuration exhibit superior damage‐tolerance characteristics. On the basis of this observation, the design concept of the bionic helical‐interlayer configuration is innovatively integrated into the design of a bionic nacre‐like honeycomb structure. By systematically studying different spiral angles of honeycomb's interlayer stacking forms, their influence on the structural performance is deeply discussed with four‐point bending tests. Mechanical samples are carefully prepared using short carbon fiber reinforced polyamide composites (i.e., PA6‐CF) through conventional fused filament fabrication (FFF) 3D printing technology, where the accuracy and reliability of the designed bio‐inspired samples are ensured. The experimental results reveal significant improvements in bending strength and elastic modulus across various bionic nacre‐like honeycomb spiral structures compared to uniformly overlap configurations. In particular, the SH‐7.5 sample shows a remarkable 35.47% increase in bending strength and a 65.10% increase in elastic modulus over the SH‐11.25 sample. SEM‐based microstructural analyses are carried out to further explore the fracture mode of the carbon fibers, implied the helical configuration adopted in the nacre‐like honeycomb structure enhances the flexural resistant ability of the PA6‐CF composites. The findings above bear important guiding significance and reference value for the design of lightweight and high damage‐tolerance composite structures. Highlights: A novel bio‐inspired structure is implemented to improve the mechanical performance of fused filament fabricated polyamide composites, where the bionic spiral helical configuration is integrated into high‐fracture‐resistance nacre‐like honeycomb structures.Mechanical testing results indicate that a helix angle under 10° results in a significant improvement in the structural performance of flexural strength.Microstructural analysis reveals that the helical configuration enhances the load‐bearing functionality of reinforcing carbon fibers in the printed polyamide composites.FFF 3D printing enables further implementation of the proposed bio‐inspired novel structure for lightweight and damage‐tolerant composite applications with high customization demands. [ABSTRACT FROM AUTHOR]

The content of selenium (Se) in most horticultural crops is low. To improve Se uptake in fruit trees, we investigated the impact of water extract derived from Nasturtium officinale R. Br. straw on the growth and Se uptake of peach seedlings under Se‐enriched soil by a pot experiment. The water extract of N. officinale straw exhibited notable effects on various growth parameters and Se accumulation in peach seedlings, with the most significant outcomes observed at a 200‐fold dilution. Specifically, the extract led to substantial enhancements in biomass, photosynthetic pigment content, antioxidant enzyme activity, and soluble protein content in peach seedlings. Remarkably, the 200‐fold dilution of N. officinale straw extract resulted in a 60.78% increase in root biomass and a 31.26% increase in shoot biomass when compared to the control. Moreover, the water extract augmented the levels of total Se, inorganic Se, and organic Se, along with the activities of Se metabolism‐related enzymes in peach seedlings. Among various tested dilutions, the 300‐fold and 400‐fold dilutions of N. officinale straw extract exhibited the highest total Se contents in roots and shoots, respectively, indicating increments of 97.26% and 44.08% over their respective controls. Additionally, correlation and gray relational analyses unveiled significant associations between peroxidase activity, soluble protein content, chlorophyll a content, chlorophyll a/b ratio, and the total shoot Se content. In conclusion, the water extract of N. officinale straw holds substantial potential for promoting the growth and Se uptake in peach seedlings, with the best concentration of 300‐fold dilution. [ABSTRACT FROM AUTHOR]

Selenium (Se) is an important trace element for human body, and the fruit Se source is one option for human Se supplementation. To increase grapevine uptake of Se, grape seedlings were transplanted in soils supplemented with sodium selenite, and the concentrations of 0, 1, 2, 4, and 6 g L−1 chitosan were sprayed on grapevine seedling leaves. Next, the effects of chitosan on grapevine Se uptake were studied. The chitosan‐based foliar application increased the biomass, photosynthetic pigment content, antioxidant enzyme activity, and soluble protein content of grapevine. Chitosan application also increased the total Se, inorganic Se, and organic Se contents in grapevine. However, while the root organic Se was increased, the shoot inorganic Se was decreased. Compared to the control, the concentrations of 1, 2, 4, and 6 g L−1 chitosan increased the shoot total Se content by 9.29%, 12.39%, 17.70%, and 14.16%, respectively. Chitosan application also increased the nitrogen (N), phosphorus (P), and potassium (K) contents in grapevine. Moreover, correlation, gray relational, principal component, and cluster analyses revealed that the root total Se, shoot total N, and root total K contents were the top three indicators closely associated with the shoot total Se content. Therefore, foliar‐based chitosan application on grape seedlings can promote the Se uptake in grapevine under sodium selenite supply, and 4 g L−1 is the best concentration. [ABSTRACT FROM AUTHOR]

The effects of exogenous strigolactone (using strigolactone analog GR24) on the cadmium (Cd) accumulation in Solanum nigrum var. humile were studied by a pot experiment. The Cd treatment (0.1 mg/L) inhibited the growth of S. nigrum var. humile, indicating that 0.1 mg/L produced the stress to S. nigrum var. humile. Spraying GR24 at 1 μmol/L did not change plant dry biomass, increased the photosynthetic pigment content and catalase activity, and decreased the peroxidase activity under Cd stress. By contrast, spraying GR24 at 2 μmol/L had no significant effects on these parameters. The superoxide dismutase activity was decreased by GR24 at 1 μmol/L, but increased by GR24 at 2 μmol/L. Nevertheless, both GR24 at 1 and 2 μmol/L increased the Cd contents, bioconcentration factors, and Cd extractions in various plant organs. Compared to Cd treatment, GR24 at 1 and 2 μmol/L increased the shoot Cd extraction by 20.0% and 14.5%, respectively. So, application of exogenous strigolactone could improve the phytoremediation capacity of S. nigrum var. humile. Correlation and grey relational analyses showed that the root Cd content, shoot Cd content, and root Cd extraction were the top three parameters closely related to the shoot Cd extraction. These findings suggest that exogenous strigolactone can effectively promote the Cd accumulation in S. nigrum var. humile, presenting a promising solution to enhance its phytoremediation capacity. [ABSTRACT FROM AUTHOR]

γ‐aminobutyric acid (GABA) has shown promise in enhancing crop tolerance to heavy metal stress. To improve the cadmium (Cd) phytoremediation capacity of hyperaccumulator Solanum nigrum var. humile, the effects of exogenous GABA on the growth and Cd accumulation of S. nigrum var. humile were studied. When exposed to Cd stress (0.1 mg/L) through irrigation, S. nigrum var. humile exhibited inhibited growth, characterized by decreased biomass and contents of photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid). However, the application of exogenous GABA at 1 and 2 g/L increased various organs biomass and photosynthetic pigment content of S. nigrum var. humile to certain degree under Cd stress. Compared with the Cd treatment, the concentrations of 1 and 2 g/L GABA increased the shoot biomass by 8.24% and 16.62%, respectively. GABA also increased the Cd contents, bioconcentration factors, and Cd extractions in various organs of S. nigrum var. humile. Compared with the Cd treatment, the concentrations of 1 and 2 g/L GABA increased the shoot Cd extraction by 17.66% and 24.47%, respectively. Moreover, correlation and gray relational analyses showed that the shoot biomass, chlorophyll b content, and total chlorophyll content were the top three parameters closely related to shoot Cd extraction. These findings suggest that GABA can alleviate Cd‐induced stress in S. nigrum var. humile, thus enhancing its phytoremediation capacity for Cd‐contaminated soils. [ABSTRACT FROM AUTHOR]

To promote the selenium (Se) uptakes in fruit trees under Se-contaminated soil, the effects of water extract of Fagopyrum dibotrys (D. Don) Hara straw on the Se accumulation in peach seedlings under selenium-contaminated soil were studied. The results showed that the root biomass, chlorophyll content, activities of antioxidant enzymes, and soluble protein content of peach seedlings were increased by the F. dibotrys straw extract. The different forms of Se (total Se, inorganic Se, and organic Se) were also increased in peach seedlings following treatment with the F. dibotrys straw extract. The highest total shoot Se content was treated by the 300-fold dilution of F. dibotrys straw, which was 30.87% higher than the control. The F. dibotrys straw extract also increased the activities of adenosine triphosphate sulfurase (ATPS), and adenosine 5'-phosphosulfate reductase (APR) in peach seedlings, but decreased the activity of serine acetyltransferase (SAT). Additionally, correlation and grey relational analyses revealed that chlorophyll a content, APR activity, and root biomass were closely associated with the total shoot Se content. Overall, this study shows that the water extract of F. dibotrys straw can promote Se uptake in peach seedlings, and 300-fold dilution is the most suitable concentration. The water extract of Fagopyrum dibotrys (D. Don) Hara straw promoted the selenium (Se) uptake in peach seedlings under selenium-contaminated soil. The concentration of F. dibotrys straw extract showed a quadratic polynomial regression relationship with the total root and shoot Se. Furthermore, chlorophyll a content, APR activity, and root biomass were closely associated with the total shoot Se. This study shows that water extract of F. dibotrys straw can promote Se uptake in peach seedlings, and 300-fold dilution is the most suitable concentration. [ABSTRACT FROM AUTHOR]

In this paper, we irradiated K0.4Co1.3[Fe(CN)6]·nH2O with infrared light ([KCoFePBA]IIP) during the preparation process and compared them with normal preparations ([KCoFePBA]NP). XRD results show that the samples conform to the Fm-3 m space group, and the lattice constants are 10.230 Å ([KCoFePBA]NP) and 10.225 Å ([KCoFePBA]IIP), respectively. According to the results of Mössbauer spectroscopy, due to the induction of infrared light during the preparation process, part of the electrons are transferred from Co2+ to Fe3+, the paramagnetic Fe3+ (S = 1/2)-CN-Co2+ (S = 3/2) changes to the diamagnetic Fe2+ (S = 0)-CN-Co3+ (S = 0) by charge transfer. The magnetization measurement shows that the magnetization of [KCoFePBA]IIP is significantly less than that of [KCoFePBA]NP. At 300 K, the theoretical magnetic moments of [KCoFePBA]NP and [KCoFePBA]IIP are 4.60 µB and 4.37 µB, respectively. The difference in magnetism can be attributed to the charge transfer caused by infrared irradiation during the preparation process. [ABSTRACT FROM AUTHOR]

In this paper, La 1 − x CaxFeO3 (x = 0 , 0.1, 0.2, 0.3, 0.4, 0.5) perovskite samples were synthesized by sol–gel method. X-ray diffraction (XRD), transmission electron microscopy (TEM) and Mössbauer were used for measuring. XRD measurement shows that the unit cell volume of LaFeO3 gradually decreases with increasing Ca content. The morphology of the sample was observed by TEM, and there were significant changes in volume and size of the samples with different calcium contents. Mössbauer spectrum study found that with the gradual increase of Ca content, Fe 3. 5 + and Fe 4 + were formed in the sample. The study in this paper will provide a reference for future research on the effect of different calcium contents on the electronic structure of lanthanide ferrite. [ABSTRACT FROM AUTHOR]

We propose a theoretical framework to illustrate the impact of trade policy uncertainty on pollution emissions of export enterprises and the underlying mechanism. The magnitudes of the effect and the proposed channels are empirically estimated using the case of the formal establishment of China‐ASEAN free trade area and sulfur dioxide (SO2) emission intensity as a measure of pollution emission intensity. Our analysis relies on high‐precision micro enterprise‐level data and the difference‐in‐difference methodology. The results show that China‐ASEAN free trade area effectively reduced the trade policy uncertainty and the SO2 emission intensity of Chinese enterprises exporting to ASEAN. The study also shows that the export enterprises of different trade modes, ownership types, regions, factor intensity, and pollution intensity industries show significant heterogeneity in the extent of the reduction in the SO2 emission intensity. The mechanism test reveals that the trade policy uncertainty decline mainly reduces the emission intensity of SO2 by raising the competitive and learning effects. The contribution of the learning effect is higher and accounts for 32.54% of the total effect. In addition, through dynamic decomposition at the industry level, we found that the contribution rate of resource allocation effect among enterprises in reducing the total emission intensity of SO2 of enterprises exporting to ASEAN at the industry level is 52.22%. This effect is perhaps the most significant way trade policy uncertainty impacts the SO2 pollution emission intensity. [ABSTRACT FROM AUTHOR]

Reduction of regional trade policy uncertainty is critical for promoting Chinese export enterprise productivity and will help the economy enter the high‐quality development stage. We use the case of the China–ASEAN Free Trade Area to empirically tests the impact of the reduction of regional trade policy uncertainty on the productivity of Chinese export enterprises. We apply the difference‐in‐difference method to micro‐enterprise level data from the "China industrial enterprise database" and "China Customs enterprise database" for 2007–2013. Our analysis and results show that establishing the China–ASEAN Free Trade Area has dramatically reduced regional trade policy uncertainty, significantly impacting the productivity of Chinese enterprises exporting to ASEAN. The results also show that enterprises with different ownership types, regions, factor density, and pollution emission intensity show significant heterogeneity in the level of productivity improvement. Applying a mechanism test, we found that the promotion of productivity from a reduction of regional trade policy uncertainty is achieved through the learning effect, the competition effect, and improving the trade environment of imported intermediate goods. The learning effect mechanism has the highest contribution, accounting for 39.01% of the net effect. The empirical results provide novel insight into promoting the productivity of Chinese enterprises exporting to ASEAN from the perspective of reducing regional trade policy uncertainty. [ABSTRACT FROM AUTHOR]