During the preparation of atomically dispersed Fe–N–C catalysts, it is difficult to avoid the formation of iron‐carbide‐containing iron clusters (“FexC/Fe”), along with the desired carbon matrix containing dispersed FeNx sites. As a result, an uncertain amount of the oxygen reduction reaction (ORR) occurs, making it difficult to maximize the catalytic efficiency. Herein, sulfuration is used to boost the activity of FexC/Fe, forming an improved system, “FeNC–S–FexC/Fe”, for catalysis involving oxygen. Various spectroscopic techniques are used to define the composition of the active sites, which include Fe–S bonds at the interface of the now‐S‐doped carbon matrix and the FexC/Fe clusters. In addition to outstanding activity in basic media, FeNC–S–FexC/Fe exhibits improved ORR activity and durability in acidic media; its half‐wave potential of 0.821 V outperforms the commercial Pt/C catalyst (20%), and its activity does not decay even after 10 000 cycles. Interestingly, the catalytic activity for the oxygen evolution reaction (OER) simultaneously improves. Thus, FeNC–S–FexC/Fe can be used as a high‐performance bifunctional catalyst in Zn–air batteries. Theoretical calculations and control experiments show that the original FeNx active centers are enhanced by the FexC/Fe clusters and the Fe–S and C–S–C bonds.

Serum microRNAs have been identified as potential cancer biomarkers. However, the detailed mechanism by which expression of microRNAs contributes to the development and diagnosis of NSCLC remains unknown. This study was to identify specific miRNAs for diagnosing or predicting the prognosis of NSCLC patients and their correlation between miRNA expression in tissues and serums. Six matched cancer and noncancerous tissues from NSCLC patients were analyzed by miRNA microarray. Among these, three miRNAs (miR-21, miR-141, and miR-200c) were examined in 70 NSCLC paired samples (cancer, normal tissue, and serum) and 44 serum samples of normal volunteers by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Consisting with the microarray results, the expression levels of miR-21, miR-141, and miR-200c in NSCLC were higher than those in normal tissues. While the level of serum miR-21 was increased in cancer patients as compared with that in normal counterpart, expression of miR-141 and miR-200c showed lower levels in serums from cancer patients. Overexpression of serum miR-21 was strongly associated with lymph node metastasis and advanced clinical stage of NSCLC. Finally, log-rank and Cox regression tests demonstrated that high expressions of tumor miR 21 and miR-200c or serum miR-21 were associated with a poor survival in NSCLC patients. Our results suggest that tumor miR-21, miR-141, miR-200c, and serum miR-21 may be potential novel biomarkers for the diagnosis of NSCLC. In addition, this study, for the first time, identifies a significant role of the tumor miR-200c played in predicting prognosis in patients with NSCLC.

a b s t r a c t a r t i c l e i n f oImplementation of the Grain-for-Green project has resulted in significantly increased vegetative cover on the Loess Plateau of China during the past few decades. The plant communities influence soil moisture recharge and usage processes, particularly the input process, which is directly related to transformation of the limited precipitation into available soil water in the semi-arid Loess Plateau. A study to measure soil moisture dynamics of typical land cover types associated with precipitation events was conducted in a re-vegetated catchment area. Smart probes were inserted at 6 different depths below the ground surface under grass (Andropogon), subshrub (Artemisia scoparia), shrub (Spiraea pubescens), tree (Robinia pseudoacacia), and crop (Zea mays) vegetation to record volumetric soil moisture at 10-minute intervals for a period of 60 days during the growing season in 2011. The advance of the wetting front and total accumulated infiltrated water were measured. The rainfall events were sporadic with widely different intensities, and the soil moisture was replenished mainly by 3-4 heavy precipitation events during July and August. The mean soil moisture content profiles of the 5 vegetation types can be ordered as crop > grass > subshrub> tree> shrub and this relationship displayed time stability. The different land cover types clearly influenced the water infiltration and water input amounts in the re-vegetated area. The subshrub site showed the highest total infiltration amount (164 mm) with precipitation (227 mm) during the study period. The grass site had an infiltration amount of 156 mm. The tree site had a total precipitation of 154 mm and an infiltration amount of 97 mm. The infiltration amount was 136 mm for the shrub site and was the lowest (83 mm) for the crop site. Natural grasses displayed a rapid infiltration rate and the wetting front was able to reach a greater depth.

a b s t r a c t a r t i c l e i n f oSoil erosion is a critical environmental problem of the Loess Plateau, China. As an important project for soil and water conservation in the semi-arid environment, the Grain-for-Green extensively transformed a wide range of farmland into vegetated land after the 1980s. Yet, the effects of vegetation restoration on soil erosion reduction are not well understood. In this study, we monitored runoff and sediment yield at sites restored with six typical restoration vegetation types including shrubs (Armeniaca sibirica, Spiraea pubescens and Artemisia coparia), grasses (Andropogon), and shrub-grass-compounds (Andropogon and A. coparia) in the Loess Plateau. We employed structural equation modelling (SEM) to systematically analyze the relative effects of precipitation and vegetation on soil erosion. The results showed that the runoff and sediment yield at the grasslands were significantly higher than other cover types. The shrub cover had the strongest soil conservation capacity of all restoration vegetation. SEM results showed varying impacts of precipitation (i.e., total amount and erosive rainfall intensity) on runoff and soil erosion under different vegetation types owing to differences in canopy structure and surface litter layer. Our study quantitatively revealed the interactive effects of precipitation and vegetation on runoff and sediment, which may be beneficial to conserving available water and soil resources in the semiarid environment.