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991.
Supercapacitors: Large‐Scale Conductive Yarns Based on Twistable Korean Traditional Paper (Hanji) for Supercapacitor Applications: Toward High‐Performance Paper Supercapacitors (Adv. Energy Mater. 27/2018) 下载免费PDF全文
992.
Long‐term nitrogen fertilization decreases bacterial diversity and favors the growth of Actinobacteria and Proteobacteria in agro‐ecosystems across the globe 下载免费PDF全文
Zhongmin Dai Weiqin Su Huaihai Chen Albert Barberán Haochun Zhao Mengjie Yu Lu Yu Philip C. Brookes Christopher W. Schadt Scott X. Chang Jianming Xu 《Global Change Biology》2018,24(8):3452-3461
Long‐term elevated nitrogen (N) input from anthropogenic sources may cause soil acidification and decrease crop yield, yet the response of the belowground microbial community to long‐term N input alone or in combination with phosphorus (P) and potassium (K) is poorly understood. We explored the effect of long‐term N and NPK fertilization on soil bacterial diversity and community composition using meta‐analysis of a global dataset. Nitrogen fertilization decreased soil pH, and increased soil organic carbon (C) and available N contents. Bacterial taxonomic diversity was decreased by N fertilization alone, but was increased by NPK fertilization. The effect of N fertilization on bacterial diversity varied with soil texture and water management, but was independent of crop type or N application rate. Changes in bacterial diversity were positively related to both soil pH and organic C content under N fertilization alone, but only to soil organic C under NPK fertilization. Microbial biomass C decreased with decreasing bacterial diversity under long‐term N fertilization. Nitrogen fertilization increased the relative abundance of Proteobacteria and Actinobacteria, but reduced the abundance of Acidobacteria, consistent with the general life history strategy theory for bacteria. The positive correlation between N application rate and the relative abundance of Actinobacteria indicates that increased N availability favored the growth of Actinobacteria. This first global analysis of long‐term N and NPK fertilization that differentially affects bacterial diversity and community composition provides a reference for nutrient management strategies for maintaining belowground microbial diversity in agro‐ecosystems worldwide. 相似文献
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Dong-Yan Huang Zhi-Rao Dai Wei-Min Li Rong-Guan Wang Shi-Ming Yang 《Saudi Journal of Biological Sciences》2018,25(4):826-831
The present study was performed to investigate the effect of quercetin on nasopharyngeal carcinoma (NPC) angiogenesis. The real-time RT-PCR and enzyme-linked immunosorbent assays (ELISA) were performed to analyze the expression levels of vascular endothelial growth factor (VEGF) in nasopharyngeal carcinoma cell lines prior to and after the quercetin treatment. Effect of quercetin on the rate of cell proliferation was measured by MTT assay. It was observed that quercetin treatment at a concentration of 10 mg/mL reduced the rate of NPC039 cell viability to 36% compared to control after 24 h. The expression of VEGF and activity of NF-κB was also markedly reduced. The ability of tube formation in HUVECs was inhibited significantly on exposure to quercetin compared to the untreated cells. Therefore, quercetin plays an important role in the inhibition of NPC039 nasopharyngeal carcinoma and can be of therapeutic importance. 相似文献
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The effects of plant-derived chemicals (volatiles) on the attraction of the Spodoptera litura moth to sex pheromones were evaluated using an electroantennogram (EAG). Neuronal responses of male moths to sex pheromone mixtures (SPs) (a 9:1 mixture of synthetic (9Z,11E)-9,11-tetraddecadienyl acetate (Z9E11-14:OAc) and (9Z,12E)-9,12-tetradecadienyl acetate (Z9E12-14:OAc)) and to SPs mixtures with eight plant volatiles (benzaldehyde, (E)-β-caryophyllene, phenylacetaldehyde, 2,6-nonadienal, benzyl alcohol, racemic linalool, longifolene, and (E)-β-ocimene) were also measured. Then, wind tunnels and field trapping bioassays were conducted to determine the influence of plant volatiles on S. litura moth behavioral responses to SPs. The results indicated that benzaldehyde, phenylacetaldehyde, and benzyl alcohol significantly enhanced, and longifolene, (E)-β-caryophyllene, and (E)-β-ocimene had no significant effect on the attractions to SPs, whereas racemic linalool significantly decreased the attraction of male S. litura moths to SPs throughout the olfactory pathway. 2,6-Nonadienal significantly enhanced olfactory responses, but had no significant effect on output behavior. These findings provide foundations in utilization of plant volatiles and sex pheromones to manage the pest and other agricultural pests. 相似文献
996.
Coleosporium species cause pine needle rust. Most species have heteromacrocyclic life cycles, and 12 species use Pinus densiflora as aecial hosts. To understand the biology of rust fungi and develop better methods for controlling rust diseases, it is necessary to clarify that which Coleosporium species affect pine trees. However, Coleosporium on pine trees have rarely been identified at the species level because of their morphological similarities. We used polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) to clarify the species composition, abundance, and distribution of Coleosporium in a P. densiflora forest. We surveyed a site where several Coleosporium species might complete their life cycles. PCR-RFLP revealed four species on the pines: C. asterum, C. clematidis-apiifoliae, C. lycopodis, and C. phellodendri. Coleosporium phellodendri was distributed throughout the forest and was the most abundant. Aecia of C. phellodendri formed mainly on 2-y-old needles. The abundance and distribution of C. phellodendri appeared to be affected by the longer effective dispersal range of basidiospores and the existence of abundant inoculum sources. The age of leaves where C. phellodendri form aecia mainly was thought to be influenced by the characteristic life cycle, with aecial formation requiring 2?y after basidiospore infection. 相似文献
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Maryam Ahmadian Sihao Liu Shannon M. Reilly Nasun Hah Weiwei Fan Eiji Yoshihara Pooja Jha C. Daniel De Magalhaes Filho Sandra Jacinto Andrew V. Gomez Yang Dai Ruth T. Yu Christopher Liddle Annette R. Atkins Johan Auwerx Alan R. Saltiel Michael Downes Ronald M. Evans 《Cell reports》2018,22(11):2849-2859
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