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61.
The discovery of a possibly invasive Proscoloplos species on the French Atlantic coast led to a detailed morphological and molecular investigation. Proscoloplos consists of three nominal species, but molecular analyses of the variable ITS1 and ITS2 region revealed no clade support for samples from South Africa, France and Australia, representing at least two of these nominal species. We found no unambiguous diagnostic characters for the three different species even with scanning electron microscopy. Two main characters—first appearance of branchiae and hooks—that were used for species delineation show considerable intrapopulational variation and do not withstand critical evaluation. The obtained data and the observed regenerative capabilities point to a cautious use of the position of branchiae and hooked chaetae as taxonomic marker in Proscoloplos. After experimental bisection of animals, the recovery led to a phenotype without recognizable signs of regeneration, but neither branchiae nor hooked chaetae reoccurred at the same initial segmental position. Summarising the molecular and morphological data we suggest the synonymy of the known Proscoloplos species under the senior synonym Proscoloplos cygnochaetus Day, 1967. The enormous geographic range of this species comprises the temperate waters of the whole southern hemisphere and includes the French population. We discuss a dispersal enabled through the effective anchorage on vessels using mucous glands and chaetae possibly combined with architomic reproduction.  相似文献   
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We describe a case of Harlequin Icthyosis where the main 2D and 3D ultrasound findings were digital contractures as opposed to the more commonly described severe facial dysmorphisms. A prenatal finding of distal arthrogryposis can therefore include harlequin icthyosis as a differential diagnosis, where 3D ultrasound may then disclose the facial features more commonly associated with the condition. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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引言 北极已成为对当前气候波动和预计的全球变暖增强的影响进行评估的重要地区.原因有以下几个方面:①在过去几十年中北极经历了大幅度的变暖过程(温度平均升高3℃,而在许多地区温度升高了4~5℃);②气候预测表明气候呈现持续变暖趋势,在2080年之前年平均气温升高4~5℃;③近期的气候变暖正在影响北极的环境和经济,这些影响还会加大,并对生活方式、文化及生态系统造成影响;④北极的变化可能会影响到地球上的其它地区.  相似文献   
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Density and nutritional condition of the five carabid beetle species Agonum mülleri, Anchomenus dorsalis, Anisodactylus binotatus, Pterostichus vernalis and Poecilus cupreus was studied. Carabids were caught in sixteen 1–4-year-old wildflower areas, identified and counted, their nutritional condition was calculated and calculations were related to habitat parameters (i.e. wildflower area age, vegetation cover, soil water content, habitat size, surrounding landscape composition) and sex.Whereas the number of Anisodactylus binotatus caught responded positively to succession in wildflower areas, A. mülleri numbers tended to decrease and the other three species were unaffected. In a stepwise multiple regression species affiliation, sex and age of wildflower area explained together 98.5% of the variance in the pooled nutritional condition of Anchomenus dorsalis, Anisodactylus binotatus, A. mülleri and P. vernalis. Age of wildflower area alone explained 61.7% of the variance and age increased the nutritional condition of carabids. Correspondingly, nutritional condition of Poecilus cupreus was positively correlated with the age of wildflower area. Overall, the nutritional condition of the carabid assemblage studied increased from the first to the second year and then remained stable. To keep the proportion of 1-year-old wildflower areas low, wildflower areas should therefore be maintained for several years to improve the life conditions of carabid beetles and to enhance their beneficial effects in agroecosystems.  相似文献   
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Im Rahmen eines Untersuchungsprogrammes zur Schadstoffemission von Paraffin-, Stearin- und Bienenwachskerzen ohne Farb- und Lackbeimischungen wurden sowohl die Wachse und Dochte als auch die Brandgase dieser Kerzen auf die toxikologisch besonders relevanten Schadstoffklassen der PCDD/PCDF, PAK und kurzkettigen Aldehyde untersucht. Die toxikologische Bewertung kommt selbst bei einem angenommenen „worst case“-Szenario und unter Berücksichtigung von geltenden Grenz- und Richtwerten zu dem Ergebnis, da? von den untersuchten Kerzen kein zus?tzliches Gesundheitsrisiko ausgeht. Exhaust fumes of paraffin, beeswax and stearin candles without any further paint or decorative element were analysed for the toxicological important substance classes of PCDD/PCDF, PAH and short chain aldehydes. The candle waxes and wicks were investigated for chlorinated dioxins, furans and some known precursors. Toxicological risk assessment shows that emissions of the investigated candles are much lower than all administrative limitation values — even under “worst case conditions”. Thus, they do not produce a toxicological risk for human health.  相似文献   
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Background, aim and scope  

The applicability of the Whole Effluent Assessment concept for the proof of compliance with the “best available techniques” has been analysed with paper mill wastewater from Germany by considering its persistency (P), potentially bio-accumulative substances (B) and toxicity (T).  相似文献   
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