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781.
Endocrine disruption in wild populations of chub (Leuciscus cephalus) in contaminated French streams
Nathalie Hinfray Olivier Palluel Wilfried Sanchez Patrice Noury Perrine Geraudie François Brion 《The Science of the total environment》2010,408(9):2146-2154
The aim of this study was to assess endocrine disruptive effects in wild population of fish in five French rivers selected to represent different pollution contexts at two seasons (summer and fall). For that purpose, a panel of biometrical parameters (length, weight, and gonado-somatic index: GSI) and biochemical (ethoxyresorufin-O-deethylase: EROD, vitellogenin: VTG, and brain aromatase) and histological biomarkers (gonads histology) were used in chub (Leuciscus cephalus), a common cyprinid fish species. In fish from the reference site, EROD activity and VTG levels were low at the two seasons. Brain aromatase activities (AAs) were similar to other species and increased with increasing GSI and gonad maturation. Among the four contaminated sites, the Jalle d'Eysines River was the most impacted site. At this site, fish were exposed to estrogenic substances as demonstrated by the VTG induction in males and the arrest of development of the gonads that led to lower brain AA compared to fish from the reference site. In fish from other contaminated sites, EROD activity was induced as compared to fish from the reference site and some males had elevated concentrations of VTG. Moreover, the presence of aromatase-inhibiting compounds was demonstrated in the sediments of three contaminated sites, even if the precise nature of contaminants is not known. This study provides new data concerning endocrine disruption in wild fish populations inhabiting French rivers and demonstrates that measurements of in vivo and in vitro aromatase could be used as biomarkers of endocrine disruption in field studies. 相似文献
782.
对德国防水工程应遵循的各类规范及防水工程的分类进行了简单描述,对建筑结构防水施工规范DIN 18195进行了较详细的介绍,同时例举了德国威达公司相关的适应产品及地下防水系统案例. 相似文献
783.
Karin Kleigrewe Martina Haack Martine Baudin Thomas Mnabraz Julien Crovadore Mahmoud Masri Michael Beyrer Wilfried Andlauer Franois Lefort Corinna Dawid Thomas B. Brück Wolfram M. Brück 《International journal of molecular sciences》2022,23(18)
Flaxseeds are typically consumed either as whole flaxseed, ground flaxseed, flaxseed oil, partially defatted flaxseed meal, or as a milk alternative. They are considered a rich source of vitamins, minerals, proteins and peptides, lipids, carbohydrates, lignans, and dietary fiber, which have shown hypolipidemic, antiatherogenic, anticholesterolemic, and anti-inflammatory property activity. Here, an in vitro batch culture model was used to investigate the influence of whole milled flaxseed and partially defatted milled flaxseed press cake on the gut microbiota and the liberation of flaxseed bioactives. Microbial communities were profiled using 16S rRNA gene-based high-throughput sequencing with targeted mass spectrometry measuring lignan, cyclolinopeptide, and bile acid content and HPLC for short-chain fatty acid profiles. Flaxseed supplementation decreased gut microbiota richness with Firmicutes, Proteobacteria, and Bacteroidetes becoming the predominant phyla. Secoisolariciresinol, enterodiol, and enterolactone were rapidly produced with acetic acid, butyric acid, and propionic acid being the predominant acids after 24 h of fermentation. The flaxseed press cake and whole flaxseed were equivalent in microbiota changes and functionality. However, press cake may be superior as a functional additive in a variety of foods in terms of consumer acceptance as it would be more resistant to oxidative changes. 相似文献
784.
Yi-Hsuan Chen Peter Lennartz Kun Ling Liu Yi-Chen Hsieh Felix Scharf Rayan Guerdelli Annika Buchheit Mariano Grünebaum Fabian Kempe Martin Winter Gunther Brunklaus 《Advanced functional materials》2023,33(32):2300501
To go beyond polyethylene oxide in lithium metal batteries, a hybrid polymer/oligomer cell design is presented, where an ester oligomer provides high ionic conductivity of 0.2 mS cm−1 at 40 °C within thicker composite cathodes with active mass loadings of up to 11 mg cm−2 (LiNbO3-coated) LiNi0.6Mn0.2Co0.2 (NMC622), while a 30 µm thin scaffold-supported polymer electrolyte affords mechanical stability. Corresponding discharge capacities of the hybrid cells exceed 170 mAh g−1 (11 mg cm−2) or 160 mAh g−1 (6 mg cm−2) at rates of either 0.1 or 0.25 C. Multilayer pouch cells are projected to enable energy densities of 235 Wh L−1 (6 mg cm−2) and even up to 356 Wh L−1 (11 mg cm−2), clearly superior to other reported polymer-based cell designs. Polyester electrolytes are environmentally benign and safer compared to common liquid electrolytes, while the straightforward synthesis and affordability of precursors render hybrid polyester electrolytes suitable candidates for future application in solid-state lithium metal batteries. 相似文献
785.
Wilfried J. Bartz 《Lubrication Science》2000,12(3):215-237
Some SAE 15W‐40 multigrade oils were formulated, using polymethacrylate (PMA) viscosity index improvers of different molecular weights, with a mixture of N 150 and N 500 as the base oil. Kinematic and dynamic viscosities, borderline pumping temperatures, pour points, shear stability, and evaporation losses were measured. The results confirm that viscometric properties as well as shear stability depend strongly on the polymer concentration and molecular weight of the VI improvers. However, evaporation losses are dominated by the volatility properties of the base oil. 相似文献
786.