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61.
Eco-environmental vulnerability assessment is crucial for environmental and resource management. However, evaluation of eco-environmental vulnerability over large areas is a difficult and complex process because it is affected by many variables including hydro-meteorology, topography, land resources, and human activities. The Thua Thien – Hue Province and its largest river system, the Perfume River, are vital to the social-economic development of the north central coastal region of Vietnam, but there is no zoning system for environmental protection in this region. An assessment framework is proposed to evaluate the vulnerable eco-environment in association with 16 variables with 6 of them constructed from Landsat 8 satellite image products. The remaining variables were extracted from digital maps. Each variable was evaluated and spatially mapped with the aid of an analytical hierarchy process (AHP) and geographical information system (GIS). An eco-environmental vulnerability map is assorted into six vulnerability levels consisting of potential, slight, light, medium, heavy, and very heavy vulnerabilities, representing 14%, 27%, 17%, 26%, 13%, 3% of the study area, respectively. It is found that heavy and very heavy vulnerable areas appear mainly in the low and medium lands where social-economic activities have been developing rapidly. Tiny percentages of medium and heavy vulnerable levels occur in high land areas probably caused by agricultural practices in highlands, slash and burn cultivation and removal of natural forests with new plantation forests. Based on our results, three ecological zones requiring different development and protection solutions are proposed to restore local eco-environment toward sustainable development. The proposed integrated method of remote sensing (RS), GIS, and AHP to evaluate the eco-environmental vulnerability is useful for environmental protection and proper planning for land use and construction in the future. 相似文献
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《Bioscience, biotechnology, and biochemistry》2013,77(5):1190-1198
The Rhynchosciara americana C3-22 gene is located in an amplified domain and is developmentally expressed. The aim of the present work was to identify intrinsically bent DNA sites in a segment containing the gene promoter and downstream sequence. The results indicated that this gene is flanked by intrinsically bent DNA sites. Three bent DNA sites (b?3, b?2, and b?1) were localized in the promoter, and one was localized downstream of the gene (b+1). These sites had helical parameters that confirmed the curved structure, as well as segments with left-handed superhelical writhe. In silico analysis of the promoters of four other insect genes, which encode secreted polypeptides, showed that they all had curved structures and similar helical parameters. Correlation with other results indicates that the detected intrinsically bent DNA sites that flank the C3-22 gene might be a consensus feature of the gene structure in the amplified domains. 相似文献
64.
We investigated the synthesis and translocation of amino compounds in Parasponia, a genus of the Ulmaceae that represents the only non-legumes known to form a root nodule symbiosis with rhizohia. In the xylem sap of P. andersonii we identified asparagine. aspartate. glutamine, glutamated significant quantities of a non-protein amino acid. 4-methylglutamte(2-amino-4-methylpentanedioic acid). This identification was confirmed by two methods, capillary gas chromatography (GC) electron ionization (El) mass spectrometry (MS) and reverse phase high pressure liquid chromatography (HPLC) analysis of derivatized compounds. In leaf, root and nodule samples from P. andersonii and P. parviflora we also identified the related compounds 4-methyleneglutamate and 4-methyleneglulamine. Using 15N2 labelling and GC-Ms analysis of root nodule extracts we followed N2 fixation and ammonia assimilation in P. andersonii root nodules and observed Label initially in glutamine and subsequently in glutamate, suggesting operation of the glutamine synthetase/glutamine:2-oxoglutarate aminotransferase (GS/GOGAT) pathway. Importantly, we observed the incorporation of significant quantities of 15N into 4-methylglutamate in nodules, demonstrating the de nova synthesis of this non protein amino acid and suggesting a role in the translation of N in symbioticParasponia. 相似文献
65.
《Structure (London, England : 1993)》2021,29(9):1014-1028.e8
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66.
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《Molecular cell》2021,81(17):3604-3622.e10
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68.
P. S. GREWAL W. R. MARTIN R. W. MILLER E. E. LEWIS 《Biocontrol Science and Technology》1997,7(3):393-400
We studied the influence of entomopathogenic nematodes , Steinernema carpocapsae and S. riobravis, on natural populations of plant - parasitic nematodes (PPNs) infesting turfgrass in Georgia and South Carolina . S. riobravis applied at 6 109 infective juveniles (IJs) / acre provided up to 95 - 100% control of the root - knot , Meloidogyne sp ., sting , Belonolaimus longicaudatus, and ring nematode , Criconemella sp ., in Georgia , but S. carpocapsae had no effect . S. riobravis was as effective as the chemical nematicide , Fenamiphos (Nemacur 10G) at 4 weeks after treatment and more effective at 8 weeks after treatment . In South Carolina , both S. riobravis and S. carpocapsae applied at 1 109 IJs / acre provided up to 86 - 100 % control of the root - knot , sting and ring nematodes . Application of 6 109 IJs / acre increased control by only 4 - 14 % over the 1 109 dosage . Possible causes of differences in efficacy of S. carpocapsae at the two sites are discussed . It is concluded that S. riobravis may provide effective , predictable and economical control of PPNs in turfgrass . 相似文献
69.
Docetaxel resistance remains one of the main problems in clinical treatment of metastatic prostate cancer (PCa). Previous studies identified differently expressed lncRNAs in docetaxel-resistant PCa cell lines, while the potential mechanisms were still unknown. In the present study, we found NEAT1 was expressed at high levels in docetaxel-resistant PCa clinical samples and related cell lines. When knockdown NEAT1, cell proliferation and invasion in docetaxel-resistant PCa cells in vitro and in vivo were downregulated. Our further researches explained that NEAT1 exerts oncogenic function in PCa by competitively ‘sponging’ both miR-34a-5p and miR-204-5p. Inhibition of miR-34a-5p or miR-204-5p expression mimics the docetaxel-resistant activity of NEAT1, whereas ectopic expression of miR-34a-5p or miR-204-5p attenuates the anti-drug function of NEAT1 in PCa cells. Besides, we also found ACSL4 is a target of both miR-34a-5p and miR-204-5p, and ACSL4 was also inhibited by miR-34a-5p and miR-204-5p. Moreover, suppression of miR-34a-5p or/and miR-204-5p greatly restrained the expression of ACSL4 upon NEAT1 overexpression. Joint expression of miR-34a-5p and miR-204a-5p synergistically decreased the expression of ASCL4, indicating miR-34a-5p and miR-204a-5p collaboratively inhibit the expression of ACSL4. Innovatively, we concluded that NEAT1 contributes to the docetaxel resistance by increasing ACSL4 via sponging miR-34a-5p and miR-204-5p in PCa cells. 相似文献
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