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331.
332.
The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic
plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system
to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of
the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative
frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions
from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion
and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic
plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood
Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments,
Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general
water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or
benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower
quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values
reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially
have low nutrient levels. 相似文献
333.
Bisphenol A: emissions from point sources 总被引:14,自引:0,他引:14
Bisphenol A is widely used for the production of epoxy resins and polycarbonate plastics. Special in vitro test systems and animal experiments showed a weak estrogenic activity for Bisphenol A. Based on in vitro receptor interaction studies, the activity was estimated to be 2 x 10(-3) lower than that of estradiol. Especially aquatic wildlife could be endangered by waste water discharges. To manage possible risks arising from Bisphenol A contamination, the major fluxes need to be obtained and the contributors to the contamination of municipal treatment plants need to be determined. In this study, industrial emitters and communal waste waters were monitored simultaneously. Mixed samples were taken over periods of one week at nine sample sites. The results showed that the concentrations and fluxes were variable. The paper industry was the major Bisphenol A contributor to the influent of the waste water treatment plant. All the other fluxes measured, including two household areas, were considerably low. About 90% of the total load was removed during the waste water treatment. 相似文献
334.
Remodeling the clock: coactivators and signal transduction in the circadian clockworks 总被引:1,自引:0,他引:1
Frank Weber 《Die Naturwissenschaften》2009,96(3):321-337
335.
Ivonne Bedei Tascha Gehrke Karl-Philipp Gloning Matthias Meyer-Wittkopf Daria Willner Martin Krapp Alexander Scharf Jan Degenhardt Kai-Sven Heling Peter Kozlowski Kathrin Trautmann Kai M. Jahns Annegret Geipel Jan-Erik Baumüller Lucas Wilhelm Ingo Gottschalk Andreas Schröer Alexander Graf Aline Wolter Johanna Schenk Axel Weber Ignatia B. Van den Veyver Roland Axt-Fliedner 《黑龙江环境通报》2023,43(2):192-206
Objective
We aimed to investigate how the presence of fetal anomalies and different X chromosome variants influences Cell-free DNA (cfDNA) screening results for monosomy X.Methods
From a multicenter retrospective survey on 673 pregnancies with prenatally suspected or confirmed Turner syndrome, we analyzed the subgroup for which prenatal cfDNA screening and karyotype results were available. A cfDNA screening result was defined as true positive (TP) when confirmatory testing showed 45,X or an X-chromosome variant.Results
We had cfDNA results, karyotype, and phenotype data for 55 pregnancies. cfDNA results were high risk for monosomy X in 48/55, of which 23 were TP and 25 were false positive (FP). 32/48 high-risk cfDNA cases did not show fetal anomalies. Of these, 7 were TP. All were X-chromosome variants. All 16 fetuses with high-risk cfDNA result and ultrasound anomalies were TP. Of fetuses with abnormalities, those with 45,X more often had fetal hydrops/cystic hygroma, whereas those with “variant” karyotypes had different anomalies.Conclusion
Both, 45,X or X-chromosome variants can be detected after a high-risk cfDNA result for monosomy X. When there are fetal anomalies, the result is more likely a TP. In the absence of fetal anomalies, it is most often an FP or X-chromosome variant. 相似文献336.
Wissal Selmi Slaheddine Selmi Jacques Teller Christiane Weber Emmanuel Rivire David J. Nowak 《Ambio》2021,50(5):1035
The distribution of urban ecosystem services (UES) is often uneven across socioeconomic groups, leading to environmental justice issues. Understanding the distribution of UES across a landscape can help managers ensure an equitable distribution of services. While many past studies have focused on the distribution of green spaces in relation to socioeconomic variables, this research analyzes the distribution of UES provided by these green spaces. This research quantified air pollution removal, atmospheric carbon reduction, and surface runoff mitigation provided by urban trees in Strasbourg city (France). The provision of these three UES was studied at the census block scale by creating an index of UES delivery, which was contrasted with a constructed social deprivation index. Our results show that there is no significant association between the delivery of UES and social deprivation. Some deprived populations benefit from high UES delivery. Results also suggest that mapping associations between UES delivery and social deprivation should be integrated with future development plans to enhance the equitable distribution of UES. This study provides insights into the French context where studies about the distribution of UES at a small-area level remain lacking. 相似文献
337.
大气细粒子的快速捕集及化学成分在线分析方法研究 总被引:5,自引:0,他引:5
本文介绍了一种新型的大气细粒子快速捕集及其化学成分在线分析方法。该方法中大气细粒子与过饱和水蒸气绝热混和而增长成大粒子 ,并在气流的带动下惯性撞击到一垂直玻璃板上 ,一含有内标物的去离子水流自上而下将撞击到玻璃板上的粒子收集 ,收集液被直接输送到离子色谱、总有机碳分析仪 ,在线分析其中的化学成分。该方法每 12min可完成单个样品分析 ,每小时可连续采集分析 5个样品。离子色谱最低检测限约为 0 .0 5 μg/m3(NH+4 )到 0 .2 0 μg/m3(SO2 -4 ) ,不确定度约为 3 % ,TOC最低检测限为 5× 10 -5μg/m3,不确定度约为 3 %。真实的大气细粒子观测结果表明 ,该方法快速、简捷、灵敏度高 ,是实时监测大气中细粒子化学成分的有效工具 相似文献
338.
City dwellers'' accessibility of urban green spaces (UGS) has recently gained immense interest in research and policy. Related scientific studies thus far have focused primarily on spatial distances, largely missing considerations of UGS qualities. We analysed the entire UGS setting of Hannover considering the recreational nature quality and potential demands to identify age-appropriate green spaces by applying a geographic information system analysis of several data sets. Additionally, we assessed the accessibility of UGS for different age groups, varying recreational nature qualities, and potential demands. Results indicate that children and elderly people have poor access to UGS that offers age-related requirements to enable unrestricted nature-based recreation. Nature quality and age-related requirements play a significant role in the assessment of UGS for recreation and accessibility. We conclude that detected vulnerabilities regarding age-related recreation in cities are anchors to mainstream the issue and enhance future planning practices and research.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01808-x. 相似文献