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41.
Jaber?Aazami Abbas?Esmaili Sari Asghar?Abdoli Hormoz?Sohrabi Paul?J.?Van den?BrinkEmail author 《Environmental management》2015,56(1):260-269
The objectives of this study were to assess the biological water of the Iranian Tajan River using different metrics, i.e., a Multimetric Macroinvertebrate Index (MMI) and a traits-based method. Twenty-eight physico-chemical parameters, 10 habitat factors, and abundance of macroinvertebrates were obtained for 17 sites. The Shahid-Rajaie dam divides the Tajan River into an up- and downstream part, with different land uses. Eighteen metrics were used to represent four components of ecosystem quality, including tolerance (Hilsenhoff, SIGNAL), diversity (Margalef, Shannon–Wiener, Simpson, and Evenness), abundance (total number of taxa, individuals, Ephemeroptera, Plecoptera, Trichoptera, EPT, and Insects), and composition of assemblages (% Ephemeroptera, % Plecoptera, % Trichoptera, and % EPT Taxa). The integrated MMI was calculated by averaging the obtained scores of all indices. In the next step, we gathered information on 22 biological traits of macroinvertebrates to evaluate whether (group of) traits could be identified that are indicative for specific or general stress. Result showed a decrease in MMI from upstream (very good water quality) to downstream (bad) due to human activities. Industrial activities like pulping and papermaking operations or sand mining in the downstream part had more effects than agriculture and fish ponds in the upstream part. A redundancy analysis biplot showed the variation between the modalities of trait of macroinvertebrates and their correlation with physico-chemical parameters in Tajan River. The findings show that traits can be indicative for different kind of stress but that more effort has to be put in gathering data sets to disentangle the effect of habitat quality, pollution, and the physico-chemical properties of high- versus lowland rivers. 相似文献
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This paper presents our practical experience of expert opinion deduced from concrete field applications, concerning mainly safety and reliability modeling. First, expertise is defined and the approach used for eliciting expertise is shortly described. Quality and value of information from experts are important challenges for decision making from risk analysis. Expertise is very useful for supplying data when not enough field observations are available for estimating parameter uncertainties and quantifying risk analysis models, which are inputs to a decision-making process. Applications presented herein concern mainly the role of expert judgment in reliability. 相似文献
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Victoria A. Braithwaite Felicity Huntingford Ruud van den Bos 《Journal of Agricultural and Environmental Ethics》2013,26(1):7-23
Increasing public concern for the welfare of fish species that human beings use and exploit has highlighted the need for better understanding of the cognitive status of fish and of their ability to experience negative emotions such as pain and fear. Moreover, studying emotion and cognition in fish species broadens our scientific understanding of how emotion and cognition are represented in the central nervous system and what kind of role they play in the organization of behavior. For instance, on a macro neuro-architecture level the brains of fish species look dramatically different from those of mammals, while such a dramatic difference does not (always) occur at the level of emotion- and cognition-related behavior. Here, therefore, we discuss the evidence of emotion and cognition in fish species related to underlying neuro-architecture and the role that emotion and cognition play in the organization of behavior. To do so we use a framework encompassing a number of steps allowing a systematic approach to these issues. Emotion and cognition confer on human and non-human animals the capacity to compliment and/or override immediate reflexes to stimuli and so allow a large degree of flexibility in behavior. Systematic research on behavior that in mammals is indicative of emotion and cognition has been conducted in only a few fish species. The data thus far indicate that in these species brain-behavior relationships are not fundamentally different from those observed in mammals. Furthermore, data from other studies show evidence that behavior patterns related to emotion and cognition vary between fish species as well within fish species, related to sex and life history stage for example. From a welfare perspective, knowledge of such variability will potentially help us to design optimal living conditions for fish species kept by humans. 相似文献
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Elles M. J. Boon Hélène B. Schlecht Peter Martin Geoff Daniels Rolf H. A. M. Vossen Johan T. den Dunnen Bert Bakker Rob Elles 《黑龙江环境通报》2007,27(10):932-937
Objectives To validate the use of Real Time PCR, a widely used technique that can detect very low levels of Y chromosomal sequence, and to assess the use of a highly sensitive PCR technique, pyrophosphorolysis-activated polymerisation (PAP), for fetal sex determination using free fetal DNA (ffDNA). Methods The fetal sex was determined by Real Time PCR in 58 pregnancies using ffDNA isolated from maternal plasma. In parallel with the Real Time PCR experiments, the presence of Y chromosome sequence was also determined using PAP on 54 isolated ffDNA samples. Results Both techniques detected Y chromosome sequence at very low levels with 98% specificity and 100% sensitivity (Real Time n = 44, PAP n = 54). Furthermore, the PAP technique was shown to be more robust than the Real Time PCR as none of the samples tested failed to meet the acceptance criteria. Combining the two techniques for male fetal sex detection from maternal blood plasma increases the sensitivity and specificity to 100% in this series. Conclusions This study shows that both Real Time PCR and PAP can be used for Y chromosome detection on ffDNA. Furthermore, by using PAP in combination with Real Time PCR more reliable early prenatal sexing can be performed using ffDNA. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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L. E. M. Niers J. A. M. Smeitink J. M. F. Trijbels R. C. A. Sengers A. J. M. Janssen L. P. van den Heuvel 《黑龙江环境通报》2001,21(10):871-880
NADH:ubiquinone oxidoreductase (complex I of the mitochondrial respiratory chain) deficiency is a severe disorder with an often early fatal outcome. Prenatal diagnosis for complex I defects currently relies mainly on biochemical assays of complex I in fetal tissues such as chorionic villi (CV), and is only in a minority of cases possible by means of mutational analysis of nuclear-encoded genes of complex I. We report on our experience to date with prenatal diagnosis in pregnancies at risk for complex I deficiency. We measured complex I activity in native CV and/or cultured CV in 23 pregnancies in 15 families. In accordance with the results of the investigations in CV, 15 children were born clinically unaffected. Two prenatally diagnosed unaffected fetuses and two prenatally diagnosed affected fetuses were lost prematurely with spontaneous or provoked abortions, respectively. Two affected children were born (prenatally found to be affected). In two pregnancies a discrepancy between native and cultured cells was found. We conclude that prenatal diagnosis for complex I deficiency can be reliably performed. Pitfalls were encountered in using cultured CV as a result of maternal cell contamination (MCC). Future research on pathogenic nuclear mutations underlying complex I deficiency will extend the possibilities for prenatal diagnosis at the molecular level. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献