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Straw returning is an efficient straw usage strategy in rice-wheat rotation, but nitrogen (N) use efficiency (NUE) was decreased due to incorrect straw and N fertilizer managements. To investigate the effects of straw and N fertilizer management on root growth, N fertilizer fates, grain yield and NUE of wheat, a two-year field and micro-plot 15N-labelled experiment under three levels of N application rate (0, 180 and 240 kg N ha−1) with two basal N application stages [seeding (BN), and 3-leaf stage (TN)] and three straw treatments [no straw return (NS), straw return by rotary tillage (SR) and straw return by ploughing (SP)] was conducted. The results indicated that SP increased grain yield and NUE, and the increase was highest under TN180. SP increased N uptake by enhancing root extension and soil N supply capacity, and TN decreased 15N residual in 60–100 cm soil layer. SP and TN180 both decreased 15N fertilizer loss and increased 15N recovery. Reducing basal N and applied at third-leaf stage (TN180) under SP had the same grain yield level as conventional N management (BN240) under NS, while highly improved NUE due to more root extension in deep soil layer and less N fertilizer loss. [ABSTRACT FROM AUTHOR]

A large number of laboratory investigations related to the permeability have been conducted on the sliding zones. Yet little attention has been paid to the particular sliding zones of the slide-prone Badong Formation. Here, we experimentally investigate the permeability nature and the mechanism of seepage in the viscous sliding zone of the Huangtupo Landslide. Saturated seepage tests have been performed first with consideration of six dry densities and thirteen hydraulic gradients, in conjunction with the mercury intrusion porosimetry test and scanning electron microscopy test for the microstructure analysis after seepage. The results show that seepage in the sliding zone soil does not follow Darcy's Law, since there is a threshold hydraulic gradient (i0) below which no flow is observed and a critical hydraulic gradient (icr) over which the hydraulic conductivity (K) tends to be stable. The percentage of bound water could be responsible for the occurrence of i0 and icr. Furthermore, pore size distributions (PSD) less than 0.6 µm and between 10 and 90 µm exhibit positive and negative correlations with the i0, respectively, indicating that the i0 is related to the PSD. The mechanism accounting for this result is that pore water pressure forces fine clay particles into the surrounding large pores and converts arranged particles to discretely distributed ones, thereby weakening the connectivity of pores. The seepages in the sliding zones behave differently from that in the sliding mass and sliding bed in response to the permeability. [ABSTRACT FROM AUTHOR]

Phosphorus (P) deficit limits high wheat (Triticum aestivum L.) yields. Breeding low-P-tolerant cultivars is vital for sustainable agriculture and food security, but the low-P adaptation mechanisms are largely not understood. Two wheat cultivars, ND2419 (low-P-tolerant) and ZM366 (low-P-sensitive) were used in this study. They were grown under hydroponic conditions with low-P (0.015 mM) or normal-P (1 mM). Low-P suppressed biomass accumulation and net photosynthetic rate (A) in both cultivars, whereas ND2419 was relatively less suppressed. Intercellular CO 2 concentration did not decrease with the decline of stomatal conductance. Additionally, maximum electron transfer rate (J max) decreased sooner than maximum carboxylation rate (V cmax). Results indicate that impeded electron transfer is directly responsible for decreased A. Under low-P, ND2419 exhibited greater PSII functionality (potential activity (F v / F o), maximum quantum efficiency (F v / F m), photochemical quenching (q L) and non-photochemical quenching (NPQ) required for electron transfer than ZM366, resulting more ATP for Rubisco activation. Furthermore, ND2419 maintained higher chloroplast Pi concentrations by enhancing chloroplast Pi allocation, compared with ZM366. Overall, the low-P-tolerant cultivar sustained electron transfer under low-P by enhancing chloroplast Pi allocation, allowing more ATP synthesis for Rubisco activation, ultimately presenting stronger photosynthesis capacities. The improved chloroplasts Pi allocation may provide new insights into improve low-P tolerance. • Low-P inhibits photosynthesis of wheat by impeding electron transfer. • Low-P-tolerant cultivar has superior photosynthetic capacity than sensitive cultivar. • Tolerant cultivar allocates more Pi to chloroplasts to sustain electron transfer. • Stronger electron transfer contributes to ATP synthesis for Rubisco activation. [ABSTRACT FROM AUTHOR]

Objectives: The rapid development of drug-resistant bacteria, especially MRSA, poses severe threats to global public health. Adoption of antibiotic adjuvants has proved to be one of the efficient ways to solve such a crisis. Platensimycin and surfactin were comprehensively studied to combat prevalent MRSA skin infection.Methods: MICs of platensimycin, surfactin or their combinations were determined by resazurin assay, while the corresponding MBCs were determined by chequerboard assay. Growth inhibition curves and biofilm inhibition were determined by OD measurements. Membrane permeability analysis was conducted by propidium iodide staining, and morphological characterizations were performed by scanning electron microscopy. Finally, the therapeutic effects on MRSA skin infections were evaluated in scald-model mice.Results: The in vitro assays indicated that surfactin could significantly improve the antibacterial performance of platensimycin against MRSA, especially the bactericidal activity. Subsequent mechanistic studies revealed that surfactin not only interfered with the biofilm formation of MRSA, but also disturbed their cell membranes to enhance membrane permeability, and therefore synergistically ameliorated MRSA cellular uptake of platensimycin. Further in vivo assessment validated the synergistic effect of surfactin on platensimycin and the resultant enhancement of therapeutical efficacy in MRSA skin-infected mice.Conclusions: The combination of effective and biosafe surfactin and platensimycin could be a promising and efficient treatment for MRSA skin infection, which could provide a feasible solution to combat the major global health threats caused by MRSA. [ABSTRACT FROM AUTHOR]

Cesium manganese bromide metal halide has great potential in the field of X-ray imaging and anti-counterfeiting due to its excellent optoelectronic properties. Here, Cs 3 MnBr 5 was successfully prepared by a simple method. Uniquely a novel phenomenon based on H 2 O induced color change was discovered, Cs 3 MnBr 5 can recover from aqueous solution more than 10 times under heating, which can be used in fluorescent anti-counterfeiting applications. Furthermore, Cs 3 MnBr 5 @PDMS, prepared by the PDMS composite strategy, has been demonstrated to exhibit a stability that is 20 times greater than that of Cs 3 MnBr 5. Simultaneously, the light yield of Cs 3 MnBr 5 is evaluated to be 21688 photons/MeV. Furthermore, it has been successfully applied in non-destructive detection and biological imaging and the spatial resolution can be restored to 10 lp mm−1. • A convenient and environmentally friendly process has been used to synthesize Cs 3 MnBr 5 , which exhibits fluorescence transition in the air. • The revival of Cs 3 MnBr 5 exhibits more than 10 cyclic properties. Based on this cyclic behavior, its potential anti-counterfeiting application is demonstrated. • An environmentally friendly scintillation screen for X-ray imaging is prepared using Cs 3 MnBr 5 and PDMS, and it is successfully applied in the field of non-destructive detection and biological imaging. [ABSTRACT FROM AUTHOR]