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51.
Application of stable isotope analysis (SIA) in jellyfish allows definition of trophic patterns not detectable using gut content analysis alone, but analytical protocols require standardization to avoid bias in interpreting isotopic data. We determined δ13C and δ15N in Aurelia sp. from the northern Gulf of Mexico (30°00′N, 89°00′W–30°24′N, 88°00′W) to define differences in stable isotope composition between body parts and whole body, the effect of lipid extraction on δ13C in tissues, and fractionation values from medusa to prey. The isotopic composition of bell and whole Aurelia sp. was not different. The increase in δ13C values after lipid removal suggested a correction is needed. To aid future analyses, we derived a correction equation from empirical data for jellyfish samples. Laboratory feeding experiments indicated medusae increased +4 ‰ in δ13C and +0.1 ‰ in δ15N compared to their diet. These results suggest protocols commonly applied for other species may be inaccurate to define Aurelia sp. trophic ecology. Because Aurelia spp. are commonly found in marine ecosystems, accurately defining their trophic role by use of SIA has implications for understanding marine food webs worldwide. 相似文献
52.
Sebastián Corral David Sáez Gislaine Lam Patricia Lillo Rodrigo Sandoval Domingo Lancellotti 《毒物与环境化学》2013,95(2):344-358
It is widely known that human exposure to mercury vapor can cause neurological and neuropsychological deterioration. We have investigated if a population of Chilean artisanal gold-mining workers heavily exposed to elemental mercury (Hg0) display neurological and neuropsychological impairment. Male volunteers occupationally exposed to Hg0 (“gold miners”, n = 35) were recruited and compared with a group of unexposed workers (n = 40). Blood specimens were obtained from both groups for total mercury quantification. Upon neurological examination, 71% of the “gold miners” group showed abnormalities expressed as frontal impairment, tremor, or simultaneously frontal impairment, parkinsonism, and pyramidal syndrome. In contrast, only 16% of the individuals in the control group displayed neurological abnormalities. The “gold miners” group also showed impairment of the neuropsychological performance and the distribution of abnormal scores for almost all the neuropsychological tests applied was significantly higher in this group compared to the control group. Educational level, alcohol intake, and smoking habits did not influence the outcome of the neurological or neuropsychological examinations. Finally, despite that the higher blood mercury concentrations were found in the “gold miners” group, they were not significantly different from the values obtained in the control group. 相似文献
53.
The toxicities of copper, cadmium, and mercury ions and their binary and ternary mixtures were studied using the copepods Tigriopus fulvus. The LC50 values measured after 48 h exposure to single metal solutions revealed a toxicities rank as follows: CdT. fulvus. The combined effect of the metals was found to be antagonistic for Cu?Cd, Hg?Cd, and Cu?Cd?Hg, additive for Hg?Cu. 相似文献
54.
There is a recognised need to integrate multiple toxicity data deriving from battery bioassays into an easily understandable and single value, which may facilitate the decision-making process related to the management of contaminated sediments. In this study, two integration results systems were applied and compared: toxicity classification system (TCS) and Toxicity Test Battery integrated Index (TBI). The quality of sediments of the Taranto seas (Mar Grande and Mar Piccolo) was assessed by a battery of five test species representing different trophic levels (Dunaliella tertiolecta, Tigriopus fulvus, Corophium insidiosum, Mytilus galloprovincialis, and Anphibalanus amphitrite) and performed on three exposure phases (elutriate, porewater, and whole sediment). The integration of biological tests results with TBI showed that stations located in Mar Grande and one station in Mar Piccolo were in the high ecotoxicological risk level, according to the results obtained with TCS. The comparison of results deriving from two evaluation systems showed similarity in the ecotoxicological risk level. Only in one case there was a lack of concordance between two indices giving opposite judgments. The present study demonstrates that the use of one of the two indices can be useful to estimate and to rank hazard level for sediments. 相似文献
55.
Isabella Fabietti Giulia Grassini Sara Savelli Roberta Vicario Anita Romiti Milena Viggiano Chiara Vassallo Laura Valfrè Paola Giliberti Irma Capolupo Marco Bonito Pietro Bagolan Francesco Morini Leonardo Caforio 《黑龙江环境通报》2023,43(8):1002-1007