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301.
The distribution of total Hg (Hgt) and reactive (HgR) in Narragansett Bay, fresh water tributaries and point source discharges was determined during a synoptic survey, carried out in April, 1986. A Hg budget which includes fluvial inputs and atmospheric Hg deposition was constructed and the estuarine behavior of Hg assessed. 相似文献
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303.
Ma'ayan A Jenkins SL Neves S Hasseldine A Grace E Dubin-Thaler B Eungdamrong NJ Weng G Ram PT Rice JJ Kershenbaum A Stolovitzky GA Blitzer RD Iyengar R 《Science (New York, N.Y.)》2005,309(5737):1078-1083
We developed a model of 545 components (nodes) and 1259 interactions representing signaling pathways and cellular machines in the hippocampal CA1 neuron. Using graph theory methods, we analyzed ligand-induced signal flow through the system. Specification of input and output nodes allowed us to identify functional modules. Networking resulted in the emergence of regulatory motifs, such as positive and negative feedback and feedforward loops, that process information. Key regulators of plasticity were highly connected nodes required for the formation of regulatory motifs, indicating the potential importance of such motifs in determining cellular choices between homeostasis and plasticity. 相似文献
304.
Natural Colonization of Rice by Arbuscular Mycorrhizal Fungi in Different Production Areas 总被引:1,自引:0,他引:1
Lina Bernaola Grace Cange Michael O. Way Jeffrey Gore Jarrod Hardke Michael Stout 《水稻科学》2018,25(3):169-174
Interactions between plants and soil microorganisms can influence the other interactions in which plants participate, including interactions with herbivores. Many fungi, including arbuscular mycorrhizal fungi(AMF), form symbiotic relationships with the roots they inhabit, and potentially alter defense against pests. The objective of this study was to document the extent of root colonization by AMF on non-flooded rice plants grown under conditions typical of commercial fields. We hypothesized that AMF naturally colonized rice plants in different rice producing field locations. Rice plant samples were collected from areas across the southern United States, including Texas, Mississippi, Arkansas and two research stations in Louisiana. We quantified the amount of AMF colonization in insecticide-free rice plants over three consecutive years(2014–2016). The results revealed natural colonization of AMF in all rice producing areas. In all the three years of survey, rice-AMF associations were the greatest in Arkansas followed by Mississippi and Texas. This research will help draw attention to natural colonization of AMF in rice producing areas that can impact future rice research and production by facilitating agricultural exploitation of the symbiosis. 相似文献
305.
Grace Oluwakemi Babarinde Victoria Funmilayo Abioye Odunayo Omobitan Kassim Raji 《东北农业大学学报(英文版)》2018,(1):16-23
The list of underutilized green leafy vegetables is enormous: ranging from commonly consumed and underutilized vegetables. There are data on commonly consumed vegetables, but information is sparse on nutritional, chemical and anti-nutritional properties of less explored vegetables. This work aimed to evaluate some attributes of less explored or underutilized leafy vegetables. Some nutritional and anti-nutritional contents of 10 under-utilized leafy vegetables(Amaranthus spinosus Linnaeus, Basella alba Linnaeus, Corchorous tridens L., Cyrtosperma senegalense(Schott), Erigeron floribundus Sch, Hoslundia opposita Vahl, Lagenaria siceraria(Molina) Standl, Ocimum basilicum L., Solanum aethiopicum L. and Talinum portulacifolium(Forssk.) Asch. ex Schweinf) were investigated. Cyrtosperma senegalense had the highest protein value(5.93%). Hoslundia opposita had the highest fat content(0.54%). Amaranthus spinosus was high in β-carotene content(346.3 mg · 100 g-1); Cyrtosperma senegalense had the highest moisture content. A. spinosus had the highest ascorbic acid content(108.1 mg · 100 g-1). The highest tannin level(0.0057%) was found in C. senegalense and the lowest(0.0003%) was found in Solanum aethiopicum. Saponin was the highest in C. tridens(0.0052%) and the lowest in T. portulacifolium(0.00014%). C. senegalense and S. aethiopicum had their highest and the lowest phytate values, respectively. Although anti-nutrients could interfere with nutrient utilization, their values in these vegetables were not at toxic levels. 相似文献
306.
Effects of dietary Yucca meal on growth,haematology, non‐specific immune responses and disease resistance of juvenile Nile tilapia,Oreochromis niloticus (Linnaeus, 1758) 下载免费PDF全文
Grace W Njagi Seunghan Lee Seonghun Won Jeongwhui Hong Ali Hamidoghli Sungchul C Bai 《Aquaculture Research》2017,48(8):4399-4408
A 10‐week feeding trial was conducted to determine the effects of dietary yucca meal supplementation on growth, haematology, non‐specific immune responses and disease resistance in juvenile Nile tilapia, Oreochromis niloticus. Six isonitrogenous and isoenergetic experimental diets were formulated to contain 0% (YMS0), 0.1% (YMS0.1), 0.3% (YMS0.3), 0.5% (YMS0.5), 1% (YMS1.0) and 2% (YMS2.0) dietary yucca meal on the dry weight basis. Results of this study showed a higher growth performance for YMS0.1 group with significant differences with YMS0.5, YMS1.0 and YMS2.0 groups. In addition, whole‐body protein content of fish fed the YMS0.1 diet was significantly higher as compared to YMS0. Plasma lysozyme activity significantly increased in YMS0.1 group comparing to YMS0 and YMS0.5 groups. Respiratory burst activity of phagocytic blood cells was significantly enhanced when fish were fed the YMS0.1 diet. Results also showed that yucca meal supplementation had moderate effects on glutamic oxaloacetic transaminase and cholesterol levels. After the 14‐day challenge test with Aeromonas hydrophila, cumulative survival of fish fed YMS0.1 diet was significantly higher than that of fish fed diet YMS0, YMS1.0 and YMS2.0. These results suggest that the optimum dietary yucca meal inclusion level in the diet of juvenile Nile tilapia could be between 0.1% and 0.14% (23.9~33.4 mg kg?1 saponin) as a feed additive to promote growth, enhance the non‐specific immune responses and increase disease resistance. 相似文献