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The purpose of this research was to demonstrate a concentration effect of zinc exposure at organismal, cellular and sub-cellular levels in the eastern oyster and to find associated protein expression signatures (PES) for each concentration of zinc. Oysters were exposed to six concentrations of zinc for 48 h in a controlled environment. At the organismal level, fecal material was observed as a measure of physiological health during metal exposures. At the cellular level, lysosomal destabilization was measured using hemolymph. This cellular response was significant only at the highest concentration, when the fecal index was lowest. Protein responses were monitored in the oyster following exposure to zinc. Gill tissue was excised and homogenized, and then analyzed using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and digital image analysis. Protein expression signatures were found to be specific to each concentration. The protein responses were linked to the other biological parameters measured, each of which followed a concentration gradient of zinc. 相似文献
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Borja A Barbone E Basset A Borgersen G Brkljacic M Elliott M Garmendia JM Marques JC Mazik K Muxika I Magalhães Neto J Norling K Rodríguez JG Rosati I Rygg B Teixeira H Trayanova A 《Marine pollution bulletin》2011,62(3):499-513
In recent times many benthic indices have been proposed to assess the ecological quality of marine waters worldwide. In this study we compared single metrics and multi-metric methods to assess coastal and transitional benthic status along human pressure gradients in five distinct environments across Europe: Varna bay and lake (Bulgaria), Lesina lagoon (Italy), Mondego estuary (Portugal), Basque coast (Spain) and Oslofjord (Norway). Hence, 13 single metrics (abundance, number of taxa, and several diversity and sensitivity indices) and eight of the most common indices used within the European Water Framework Directive (WFD) for benthic assessment were selected: index of size spectra (ISS), Benthic assessment tool (BAT), Norwegian quality index (NQI), Multivariate AMBI (M-AMBI), Benthic quality index (BQI), (Benthic ecosystem quality index (BEQI), Benthic index based on taxonomic sufficiency (BITS), and infaunal quality index (IQI). Within each system, sampling sites were ordered in an increasing pressure gradient according to a preliminary classification based on professional judgement. The different indices are largely consistent in their response to pressure gradient, except in some particular cases (i.e. BITS, in all cases, or ISS when a low number of individuals is present). Inconsistencies between indicator responses were most pronounced in transitional waters (i.e. IQI, BEQI), highlighting the difficulties of the generic application of indicators to all marine, estuarine and lagoonal environments. However, some of the single (i.e. ecological groups approach, diversity, richness) and multi-metric methods (i.e. BAT, M-AMBI, NQI) were able to detect such gradients both in transitional and coastal environments, being these multi-metric methods more consistent in the detection than single indices. This study highlights the importance of survey design and good reference conditions for some indicators. The agreement observed between different methodologies and their ability to detect quality trends across distinct environments constitutes a promising result for the implementation of the WFD’s monitoring plans. Moreover, these results have management implications, regarding the dangers of misclassification, uncertainty in the assessment, use of conflicting indices, and testing and validation of indices. 相似文献
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利用2006-2017年黑龙江省闪电定位资料和日平均地面相对湿度资料,采用数理统计、Pearson相关分析、GIS空间分析技术,研究了闪电密度和强度对地面相对湿度(RH)的响应关系。结果表明:地面RH过小或过大都不利于闪电活动产生;当RH < 25%时,几乎无闪电发生,当RH < 77%时,RH增加有利于闪电活动发生,当RH>79%时,随着RH增加,闪电活动减少;当RH < 77%时,闪电密度与之呈正相关,闪电强度与之呈负相关;当RH>79%时,闪电密度与之呈负相关,闪电强度与之呈正相关;地面RH的临界值域约为77%-79%;70%≤ RH ≤ 90%区间为闪电易发湿度区间,在闪电密度与湿度相关度高的区域,闪电更趋于集中发生在闪电易发湿度区间。 相似文献
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桂北—湘南中生代玄武质岩石及其深源包体的地球化学性质和岩石成因探讨 总被引:9,自引:0,他引:9
桂北-湘南中生代玄武质岩石中含有丰富的深源包体,它们分别为橄榄岩、变形的辉长岩和中酸性片麻岩三大类,本文在论述上述岩石地球化学性质的基础上,探讨了它们之间的成因关系;寄主的中生代玄武质岩石为地幔楣榄岩部分熔融的产物,与辉长岩和中酸性片麻岩并无成因联系,后者属偶然包体,值得注意的是,深源包体中的变形辉长岩与片麻岩之间为分离结晶的成因关系,它们均为元古宙壳、幔间底侵玄武质岩浆的演化产物,其中辉长岩为底侵岩浆的堆积相,而片麻岩则为底侵岩浆经历分离结晶的堆积作用之后所剩下的残余岩浆的变质产物。 相似文献
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O'Leary BC Smart JC Neale FC Hawkins JP Newman S Milman AC Roberts CM 《Marine pollution bulletin》2011,62(12):2642-2648
We analysed the extent to which European politicians have adhered to scientific recommendations on annual total allowable catches (TACs) from 1987 to 2011, covering most of the period of the Common Fisheries Policy (CFP). For the 11 stocks examined, TACs were set higher than scientific recommendations in 68% of decisions. Politically-adjusted TACs averaged 33% above scientifically recommended levels. There was no evidence that the 2002 reform of the CFP improved decision-making, as was claimed at the time. We modelled the effects of such politically-driven decision-making on stock sustainability. Our results suggest that political adjustment of scientific recommendations dramatically increases the probability of a stock collapsing within 40 years.In 2012 European fisheries policy will undergo a once-a-decade reform. Ten years ago radical reforms were promised but the changes failed to improve sustainability. It is likely that the 2012 reform will be similarly ineffective unless decision-making is changed so that catch allocations are based on science rather than politics. 相似文献
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Dauvin JC 《Marine pollution bulletin》2012,64(3):463-471
The English Channel is part of the "Greater North Sea" sub-region in the Marine Strategy Framework Directive. However, the Channel is characterized by hydrologic, oceanographic and biogeographic features that support its division into two main entities: the western basin and the eastern basin. This paper summarizes the Channel's main natural features and principal human activities to examine the similarities and differences between both basins. The differences between the basins support an ecosystem-based management approach at the combined basin scale, rather than the present approach of separating the France and UK sides. 相似文献