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The oxygen evolution reaction (OER) is a half reaction of electrochemical water splitting that suffers from a kinetically sluggish four-electron process, and it is regarded as the efficiency-limiting step in water splitting. Herein, heterostructures of CoSe (cobalt selenide) nanoparticles and MoSe2 (molybdenum selenide) nanosheets (CoSe/MoSe2 hybrids) were fabricated through a non-metal-induced growth method. Due to the increase in the effective specific area and the electron transfer ability caused by the formation of the heterogeneous interface, the obtained CoSe/MoSe2 hybrids show superior OER performance (η = 262 mV at 10 mA cm−2) and long-term stability (20 h for continuous testing) as compared to pure CoSe, MoSe2 and physically mixed CoSe and MoSe2. Schematic energy band diagrams derived from ultraviolet photoelectron spectroscopy results further confirmed the electronic modulation between CoSe and MoSe2 and revealed that the d-band center of CoSe/MoSe2 hybrids moved closer to the Fermi level, giving rise to high charge carrier density and low intermediate adsorption energy as compared to CoSe and MoSe2. This work provides some insight into the design and synthesis of heterostructured nanomaterials from the MOF precursors. [ABSTRACT FROM AUTHOR]

Summer fallow is very common in dryland agriculture to conserve rainwater and replenish soil fertility. However, bare land and intensive rainfall during summer fallow might result in a potential risk of N loss. We used a 15N-labelling method to study the loss of residual N fertilizer during summer fallow and its use by next wheat in the Loess Plateau. Our study included three treatments: without the addition of N (N0W0), with the addition of 50 kg ha−1 N (NW0) and with the addition of 50 kg ha−1 N plus 35% more water (NW). The N fertilizer (K15NO3) in solution was injected into the soil at a depth of 35 cm of the polyvinyl chloride (PVC) columns in field. The fates of 15N were followed after summer fallow and in the next season’s wheat (Triticum aestivum L.). The summer fallow of this study was a dry summer; however, fertilizer 15N was still leached down to 40-cm depth for the NW0 treatment; and for the NW treatment, the peak of 15N fertilizer was approximately 20 cm deeper. After summer fallow, the loss of the initially applied 15N was 26% in the soil profile for the NW0 treatment; and for the NW treatment, it increased to 37%. Soil 15N abundance in 0-20 cm of the NW0 and NW treatments was higher than the N0W0 treatment, indicating the upward movement of 15N in summer fallow. After the next wheat harvest, 15N uptake by wheat in the NW treatment decreased from 21.0 to 18.6% compared to the NW0 treatment. High rainfall during summer fallow increased residual N loss during summer fallow but decreased its use by the next crop. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotubes (CNTs) and porous Co3O4 nanorod (Co3O4 p‐NR) composites are self‐assembled to form a hierarchical porous structure through a facile hydrothermal method to meet the requirements of long cycle life, high capacity, and excellent rate capability for next‐generation lithium‐ion batteries. CNTs are embedded in Co3O4 p‐NR clusters to form a 3D conductivity network, which reduces the transportation resistance of electrons and ions. Co3O4 p‐NRs are assembled from nanoparticles, which enlarge the contact area between electrode and electrolyte to provide more space to buffer the large volumetric changes associated with repeated electrochemical reactions and maintain the structural integrity. The obtained samples exhibit a high reversible capacity (1083 mA h g−1 after 140 cycles at 0.5 Ag−1), superior rate capability (521 mA h g−1 at 8 Ag−1), and excellent cyclic stability, with a capacity decay of 0.57 mA h g−1 per cycle at a high current of 1 Ag−1 over 200 cycles. The specific heterodimensional structure gives rise to a new approach to exploit high‐performance electrode materials. [ABSTRACT FROM AUTHOR]

The present study aimed to explore the effects of a stabilizing ligand, Shield-1, on the replication of recombinant varicella-zoster virus (VZV) containing FK506 binding protein (FKPB) tags in essential open reading frames (ORF) 4 and 48. A specific galactokinase (galK) selection method was conducted, following the addition of galK labels to VZV ORF4 and 48, using a SW102 VZV bacterial artificial chromosome (BAC) system. Subsequently, recombinant VZV containing FKPB tags in ORF4 and 48 was constructed by counterselection and homologous recombination. Recombinant viral plasmids containing FKPB-tagged VZV ORF4 and 48 were extracted and transfected into human acute retinal pigment epithelial ARPE-19 cells. The results demonstrated that the FKPB-tagged viral protein was rapidly degraded by proteases in recombinant virus-infected ARPE-19 cells. In addition, the recombinant VZVORF4-FKBP-ORF48-FKBP virus could not grow if a synthetic ligand of FKBP, Shield1, was not added to the ARPE-19 cell culture medium; however, the degradation of FKPB-tagged viral protein was prevented if Shield1 was added to the ARPE-19 cell culture medium, thereby allowing viral replication in ARPE-19 cells. These results indicated that Shield1 may regulate replication of recombinant VZVORF4-FKBP-ORF48-FKBP following transfection into human epithelial cells. [ABSTRACT FROM AUTHOR]

Appropriate water-saving and nitrogen management strategies are critical for achieving sustainable agricultural development in dry sub-humid areas of the Chinese Loess Plateau. The present study was conducted in 2004, 2005, 2008, and 2012 based on a long-term field experiment and aimed to investigate the coupled impacts of mulching and N fertilization on maize yield, water use efficiency (WUE), and residual soil nitrate (RSN) accumulated in the soil profile (0-200 cm). The results demonstrated that mulch is conducive to increasing summer maize yield. The plastic film-mulched ridge and straw-mulched furrow (RF) treatment significantly increased maize yield across the studied period, while the straw mulch (SM) treatment did not significantly increase maize yield until the third experimental year. Compared with SM, the RF treatment showed more significant and positive effects on maize yield, WUE, and RSN accumulated in the 0-200 cm soil depth. N fertilization significantly increased maize yield and WUE, but no significant differences were observed when 120 and 240 kg N ha were applied. The N240 treatment was characterized by relatively high NO -N accumulation in 0-200 cm soil depth and low ratios of soil nitrate in the upper to the lower soil layers, indicating a considerable potential for NO -N leaching. Averaged across years, economic optimum N fertilizer rates (Nops) were 154, 148, and 150 kg N ha for the no mulch, RF, and SM treatments, respectively. This suggested that 25.8-51.2% of N rate can be reduced while maintaining an acceptably high maize yield. Additionally, understanding NO -N depth distribution in 0-100 cm soil profile can adequately predict and represent the characteristics of NO -N accumulated in the 100-200 cm and 0-200 cm soil layers because of their significant correlations, thus saving time and money. In conclusion, the practice of RF combined with properly reduced farmers' N rate (~ 150 kg N ha) is the preferred option for maize production in the Chinese Loess Plateau, and further research is required to investigate the effects of mulching on summer maize under Nop conditions. [ABSTRACT FROM AUTHOR]