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Supplemental irrigation under a ridge-furrow (RF) cropping system is a valuable cropping practice that balances resource efficiency and high crop yield. However, the effects of nitrogen management on crop growth, yield formation, and economic benefits under RF systems have not been clearly investigated. In this study, the experiment was designed with three experimental factorials, including three cropping systems (RF, RF cropping with 80 mm irrigation; TF1, traditional flat cropping with 200 mm irrigation; and TF2, traditional flat cropping with 80 mm irrigation), two nitrogen application rates (NL, 180 kg N ha−1; NH, 240 kg N ha−1), and two fertilizer application models (B, all nitrogen fertilizers were applied basally at the pre-sowing stage; BT, nitrogen fertilizer was applied at both the pre-sowing and jointing stages at a ratio of 1:1). A two-year field experiment was conducted to investigate the effects of nitrogen fertilizer management on wheat yield, water and nitrogen utilization, and economic benefits under the RF cropping system. The results showed that the RF system significantly increased the soil moisture content and improved the water productivity (WP) and grain yield of wheat. Nitrogen reduction (NL) under the RF system did not affect the water use of the wheat compared with traditional high nitrogen application (NH) but increased the nitrogen uptake and fertilizer productivity of the wheat. Although NL led to a reduction in aboveground dry matter accumulation, it did not significantly affect the yield of wheat but increased the net income of wheat cultivation. Under NL conditions, the BT nitrogen application model promoted nitrogen uptake in wheat and ameliorated the reduction in grain protein content due to plastic film mulching, and this model is an integrated planting practice that trades off wheat yield and quality. These findings suggest that NLBT is a promising and recommendable cropping practice under RF systems considering resource utilization, high yield and quality, and economic efficiency. [ABSTRACT FROM AUTHOR]

Background: Natural products are often favored in the study of crop pests and diseases. Previous studies have shown that citronellal has a strong inhibition effect on Magnaporthe oryzae. The objective of this study was to clarify its mechanism of action against M. oryzae. Results: Firstly, the biological activity of citronellal against M. oryzae was determined by direct and indirect methods, and the results show that citronellal had a strong inhibition effect on M. oryzae with EC50 values of 134.00 mg/L and 70.48 μL/L air, respectively. Additionally, a preliminary study on its mechanism of action was studied. After citronellal treatment, electron microscopy revealed that the mycelium became thin and broken; scanning electron microscopy revealed that the mycelium was wrinkled and distorted; and transmission electron microscopy revealed that the mycelium cell wall was invaginated, the mass wall of mycelium was separated, and the organelles were blurred. The mycelium was further stained with CFW, and the nodes were blurred, while the mycelium was almost non-fluorescent after PI staining, and there was no significant difference in the relative conductivity of mycelium. In addition, chitinase was significantly enhanced, and the expression of chitin synthesis-related genes was 17.47-fold upregulated. Finally, we found that the efficacy of citronellal against the rice blast was as high as 82.14% according to indoor efficacy tests. Conclusion: These results indicate that citronellal can affect the synthesis of chitin in M. oryzae and damage its cell wall, thereby inhibiting the growth of mycelium and effectively protecting rice from rice blasts. [ABSTRACT FROM AUTHOR]

In this paper, 6061-T6 aluminum alloy and 30CrMnSiA steel are bonded by inertia radial friction welding (IRFW). The formation mechanism of the aluminum/steel friction welded joints and the effect of the welding parameters on the mechanical properties are investigated through the microstructure, microzone composition, and mechanical property analysis. The results show that no visible intermetallic compound layers (IMCs) are detected on the aluminum/steel welding interface, which may be due to Si element aggregating in the welding interface and then forming a Al−Fe−Si phase, preventing the formation and growth of an Al−Fe IMCs. Eventually, a micron ultrathin interface reaction layer composed of Al0.7Fe3Si0.3, FeAl, and Fe3Al phases is formed at the aluminum/steel welding interface. The maximum average shear strength of the joint is 176 MPa. The shear fracture is a typical ductile fracture. Properly reducing the friction speed and increasing the upsetting pressure can improve the bonding strength of aluminum/steel joints. [ABSTRACT FROM AUTHOR]

Road transport is a primary source of various forms of air pollution and climate-impacting emissions, and contains huge potential for improving the environment and combating climate change. This paper studies the environmental sustainability of road transport for a set of OECD countries over the period 2000–2014. We capture the sustainability performance of road transport in two data envelopment analysis (DEA) models, corresponding to the concepts of natural disposability and managerial disposability, respectively. Air pollution and carbon emissions are treated as undesirable outputs. The models produce two unified measures of environmental sustainability performance, accounting for transport activities and environmental impacts simultaneously. We find that the studied countries have improved their overall managerial disposability performance from 2000 to 2014, driven by technological progress and tightening regulations on fuel economy and vehicle emissions. The analysis enables us to identify best-practice and laggard countries in transport sustainability. [ABSTRACT FROM AUTHOR]

Helicobacter pylori -associated gastritis is a major threat to public health and Polygonum capitatum (PC) may have beneficial effects on the disease. However, the molecular mechanism remains unknown. Quercetin was isolated from PC and found to be a main bioactive compound. The effects of quercetin on human gastric cancer cells GES-1 were determined by xCELLigence. H. pylori -infected mouse models were established. All mice were divided into three groups: control (CG, healthy mice), model (MG, H. pylori infection) and quercetin (QG, mouse model treated by quercetin) groups. IL-8 (interleukin-8) levels were detected via enzyme-linked immunosorbent assay (ELISA). Cell cycle and apoptosis were measured by flow cytometry (FCM). Quantitative reverse transcription PCR (qRT-PCR) and Western Blot were used to detect the levels of p38MAPK (38-kD tyrosine phosphorylated protein kinase), apoptosis regulator BCL-2-associated protein X (BAX) and B cell lymphoma gene 2 (BCL-2). The levels of IL-8 were increased by 8.1-fold in a MG group and 4.3-fold in a QG group when compared with a CG group. In a MG group, G0-G1(phases of the cell cycle)% ratio was higher than a CG group while S phase fraction was lower in a model group than in a control group ( p < 0.01). After quercetin treatment, G0-G1% ratio was lower in a QG group than a MG group while S phase fraction was higher than a MG group ( p < 0.01). Quercetin treatment reduced the levels of p38MAPK and BAX, and increased the levels of BCL-2 when compared with a MG group ( p < 0.05). Quercetin regulates the balance of gastric cell proliferation and apoptosis to protect against gastritis. Quercetin protects against gastric inflammation and apoptosis associated with H. pylori infection by affecting the levels of p38MAPK, BCL-2 and BAX.