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1.
Long-term development in a Baltic fish community exposed to bleached pulp mill effluent 总被引:1,自引:0,他引:1
Observations near a Swedish pulp mill at the Bothnian Sea during 1982-1992 revealed low fish abundance and a disturbed community structure. The presence of endocrine disrupting or toxic substances in effluent water was indicated by biomarker responses, impaired reproduction and stimulated growth in perch (Perca fluviatilis). In 1992 the bleaching process was altered and a secondary treatment system was installed, improving the quality and decreasing the amount of effluent. This paper presents the results of follow-up studies during 1995-1998 with the objective to analyse any recovery of the fish community due to changes in mill operations. Although abundance and diversity of the fish community did recover, an effect of enrichment, indicated by high catches of cyprinids, was still visible in the vicinity of the mill outlet. Sexual maturation was delayed, gonad development was retarded, average growth rate was faster, and the condition factor was higher in perch caught in the vicinity of the effluent outlet, than in perch captured elsewhere. It is concluded that substances inhibiting reproduction and causing growth disturbance were still present in the effluents in effective concentrations. 相似文献
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M. Soussan J.-L. GalasM.-J. Ouvrier G. PopA. Neuman P. Weinmann 《Médecine Nucléaire》2011,35(7):401-405
Time-of-flight PET improves the image quality by increasing signal-to-noise ratio. This improvement increases with time resolution. Recent data confirm the clinical benefits of time-of-flight PET. The signal-to-noise gain has led to a dose reduction, shorter scans, better image quality especially in patients with high Body Mass Index, and improvement in detection of smaller lesions. 相似文献
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Yair Neuman Dan Assaf Yohai Cohen Mark Last Shlomo Argamon Newton Howard Ophir Frieder 《PloS one》2013,8(4)
Identifying metaphorical language-use (e.g., sweet child) is one of the challenges facing natural language processing. This paper describes three novel algorithms for automatic metaphor identification. The algorithms are variations of the same core algorithm. We evaluate the algorithms on two corpora of Reuters and the New York Times articles. The paper presents the most comprehensive study of metaphor identification in terms of scope of metaphorical phrases and annotated corpora size. Algorithms’ performance in identifying linguistic phrases as metaphorical or literal has been compared to human judgment. Overall, the algorithms outperform the state-of-the-art algorithm with 71% precision and 27% averaged improvement in prediction over the base-rate of metaphors in the corpus. 相似文献
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Nerve growth factor (NGF) induces the redistribution of F-actin in rat pheochromocytoma PC12 cells within 2-10 min, whereas epidermal growth factor (EGF) has no effect on microfilament organization. This redistribution of F-actin in PC12 cells is not protein synthesis dependent, but can be blocked by methyltransferase inhibitors. 相似文献
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Neuman Josh Roeder Nicole Richardson Brittany Quattrin Teresa Hamilton John Thanos Panayotis K. 《Neurochemical research》2022,47(10):3003-3011
Neurochemical Research - Dopamine is an important neuromodulator in the brain that binds to dopamine D1-like receptors (D1, D5) as well as dopamine D2-like receptors (D2, D3, D4). The D2 receptor... 相似文献
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