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191.
Brouwers MM Besselink H Bretveld RW Anzion R Scheepers PT Brouwer A Roeleveld N 《Environment international》2011,37(3):557-564
Measurements of estrogenic and androgenic activities in total plasma with Chemically Activated LUciferase gene eXpression (CALUX?) bioassays could provide biologically relevant measures for exposure to endocrine disruptors in epidemiologic studies. The objective of this study was to explore the effects of a variety of sources of potential endocrine disruptors on estrogenic and androgenic activities in total plasma measured by CALUX?. Plasma samples and interview data on sources of potential endocrine disruptors were collected from 108 men with different exposures profiles. CALUX? measurements (BioDetection Services) involved human U2-OS cell lines controlled by the estrogen receptor alpha and the androgen receptor. Mean differences (beta) in 17β-estradiol equivalents (EEQs) and dihydrotestosterone equivalents (AEQs) between exposure groups were estimated using general linear models. Mean plasma AEQs and EEQs were 9.1×10(-1)ng/ml and 12.0pg/ml, respectively. Elevated AEQs were found in smokers (beta 1.9 (95%CI 0.1-3.6)×10(-1)ng/ml) and heavy drinkers (1.4 (0.2-3.1)×10(-1)ng/ml), and in men occupationally exposed to disinfectants (1.6 (0.3-3.5)×10(-1)ng/ml) or welding/soldering fumes (1.4 (-0.2-2.9)×10(-1)ng/ml). Occupational exposure to pesticides, disinfectants, and exhaust fumes seemed to be associated with increased plasma EEQs: 1.5 (-0.2-3.2)pg/ml, 2.1 (0.2-3.9)pg/ml, and 2.9 (0.6-5.2)pg/ml, respectively. Moderate to high plasma dioxin levels, measured in a subgroup by the dioxin-responsive CALUX?, were accompanied by a 20% increase in AEQs. This is the first study in which CALUX? was used to assess hormone activities in total plasma. Although the results are not yet readily interpretable, they indicate that these measurements can be valuable for epidemiologic studies on endocrine disruptors and give direction for further research. 相似文献
192.
Annekatrin Wagner Stephan Hülsmann Lothar Paul Rüdiger J. Paul Thomas Petzoldt René Sachse Thomas Schiller Bettina Zeis Jürgen Benndorf Thomas U. Berendonk 《Marine Biology》2012,159(11):2543-2559
To predict the coherence in local responses to large-scale climatic forcing among aquatic systems, we developed a generalized approach to compare long-term data of dimictic water bodies based on phenomenologically defined hydrographic events. These climate-sensitive phases (inverse stratification, spring overturn, early thermal stratification, summer stagnation) were classified in a dual code (cold/warm) based on threshold temperatures. Accounting for a latitudinal gradient in seasonal timing of phases derived from gradients in cumulative irradiation (2.2?days per degree latitude), we found a high spatial and temporal coherence in warm–cold patterns for six lakes (84?%) and the Baltic Sea (78?%), even when using the same thresholds for all sites. Similarity to CW-codes for the North Sea still was up to 72?%. The approach allows prediction of phase-specific warming trends and resulting instantaneous or time-delayed ecological responses. Exemplarily, we show that warming during early thermal stratification controls food-web-mediated effects on key species during summer. 相似文献
193.
194.
The cardinalfish Siphamia versicolor (Perciformes: Apogonidae) forms a bioluminescent symbiosis with the marine luminous bacterium Photobacterium mandapamensis, harboring the bacteria in a ventral, disc-shaped light organ and using the bacterial light apparently for counterillumination
and attracting prey. Little definitive information has been available on the developmental and microbiological events surrounding
the initiation of symbiosis, a critical stage in the life history of the fish, in S. versicolor or any of the many other species of bacterially luminous fish. To identify the stage at which light organ formation begins,
to determine the origin of cells forming the light organ, and to characterize its bacterial colonization status during development,
early developmental stages of S. versicolor obtained and reared from wild-caught mouth-brooding males were examined with histological and microbiological methods. A
light organ primordium was not evident in embryos, post-embryos, or pre-release larvae, whereas the light organ began to form
within 1 day of release of full-term pre-flexion larvae from the mouths of male fish. Analysis of post-release larvae revealed
that the light organ arises from a proliferation and differentiation of intestinal epithelial cells, and that it quickly develops
structural complexity, including the formation of chambers and gaps contiguous with the intestinal epithelium. However, the
nascent light organ remained uncolonized by the symbiotic bacteria through several days of post-release development, even
in the presence of high numbers of the symbiotic bacteria. These results demonstrate that the inception of light organ formation
in S. versicolor occurs independently of its symbiotic bacteria and that receptivity to bacterial colonization apparently requires substantial
post-release development of the light organ. Larvae therefore most likely acquire their symbiotic bacteria from seawater,
during or shortly after the transition from the pre-flexion to the flexion developmental stage. 相似文献
195.
Benjamin Linsky James Littlepage Arland Johannes Rasool Nekooi Paul Lincoln 《Journal of the Air & Waste Management Association (1995)》2013,63(9):918-924
Dry quenching of incandescent coke after it has been pushed from the coking ovens is a proved, reliable process that is presently being used in several industrialized countries. Foremost among dry quenching’s advantages are: (1) virtual elimination of air pollutants emitted during quenching; (2) elimination of potential water pollution associated with wet quenching; (3) improvements in the working environment; (4) saving substantial amounts of energy in usable forms; (5) producing more usable coke that is superior to wet-quenched coke. By continuously circulating inert gases through a cooling chamber that contains hot coke, dry quenching recovers waste-heat energy that can be used to produce steam, to produce electricity, to preheat combustion air, to preheat coal, to dry coal, and to preheat feed water supplied to fuel-fired boilers. The pay-out period on the capital investment (approximately $7,100,000) for an installation capable of processing 5500 tons of coke/day is less than four years. 相似文献
196.
Nityananda Mondal Mayalagu Rajkumar Jun Sun Sourav Kundu P. S. Lyla Seyed Ajmal Khan Jean Paul Trilles 《Environmental monitoring and assessment》2010,171(1-4):471-486
The present study about the gammarid amphipods of Vellar and Uppanar estuaries was performed during two seasons (pre-monsoon and post-monsoon, 2005–2006), respectively, in nine habitats: five in the Vellar estuary and four in the Uppanar estuary. Amphipod samples were collected from sediments, oyster beds, seaweeds, sea grass, and mangroves. A total of 29 species of gammarid amphipods were collected in each area. The surface water temperature ranged from 16°C to 26°C, the salinity from 20 to 32 psu, and the pH between 7.5 and 8.3. Dissolved oxygen ranged from 5.3 to 7.8 ml/l. The maximum abundance of amphipods was observed during the pre-monsoon (July to September) in Vellar mangrove, and it was minimum during the pre-monsoon in Uppanar sea grass. It was found that several physicochemical factors, such as salinity, temperature, dissolved oxygen, pH, and the substrate have a marked effect on the distribution and the relative abundance of amphipods. The ranges of species diversity, richness, dominance, and evenness in the Vellar and Uppanar estuaries were 1.58–4.15, 1.82–5.29, 0–0.11, and 0.96–1, respectively. Using multivariate analyses, in each estuary, it was possible to identify different communities of amphipod species according to their habitats. 相似文献
197.
Richard D. Siegel John R. Ehrenfeld Paul Morgenstern 《Journal of the Air & Waste Management Association (1995)》2013,63(3):256-259
Initial implementation plans provided for particulate reduction largely through the imposition of emission limitations on industrial processes, large steam generators, and solid waste disposal, requiring, in turn, application of control equipment for compliance. In many urban areas, this approach is not adequate to achieve the secondary air quality standards so that a more general strategy must be employed. Such strategy may include restrictions on fuel burning, combustion equipment, maintenance programs, utility steam distribution, etc. The potential abatement achievable through such strategies is described using Boston as a case study. Cost and technical factors associated with each strategy are discussed. 相似文献
198.
Justin M. Langridge R. Joel Gustafsson Paul T. Griffiths R. Anthony Cox Richard M. Lambert Roderic L. Jones 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):5128-5131
The photoenhanced uptake of nitrogen dioxide (NO2) to the surface of commercially available self-cleaning window glass has been studied under controlled laboratory conditions. This material is one of an array of modern building products which incorporate titanium dioxide (TiO2) nanoparticles and are finding increasing use in populated urban areas. Amongst the principal drivers for the use of these materials is that they are thought to facilitate the irreversible removal of pollutants such as NO2 and organic molecules from the atmosphere and thus act to remediate air quality. While it appears that TiO2 materials do indeed remove organic molecules from built environments, in this study we show that the photoenhanced uptake of NO2 to one example material, self-cleaning window glass, is in fact accompanied by the substantial formation (50–70%) of gaseous nitrous acid (HONO). This finding has direct and serious implications for the use of these materials in urban areas. Not only is HONO a harmful respiratory irritant, it is also readily photolysed by solar radiation leading to the formation of hydroxyl radicals (OH) together with the re-release of NOx as NO. The net effect of subsequent OH initiated chemistry can then be the further degradation of air quality through the formation of secondary pollutants such as ozone and VOC oxidation products. In summary, we suggest that a scientifically conceived technical strategy for air quality remediation based on this technology, while widely perceived as universally beneficial, could in fact have effects precisely opposite to those intended. 相似文献
199.
New fossil spiders (Arachnida: Araneae) from Middle Jurassic (ca. 165 Ma) strata of Daohugou, Inner Mongolia, China are described as Eoplectreurys gertschi gen. et sp. nov. and referred to the modern haplogyne family Plectreuridae. This small family is restricted to southwestern USA, Mexico, and the adjacent Caribbean area today and hitherto has only a sparse Cenozoic fossil record. The morphology of Eoplectreurys is remarkably similar to modern forms and thus demonstrates great evolutionary conservatism. This new discovery not only extends the fossil record of the family by at least 120 Ma to the Middle Jurassic but also supports the hypothesis of a different distribution of the family in the past than today and subsequent extinction over much of its former range. 相似文献
200.
Phototransformation of the herbicide metsulfuron methyl was investigated on glass surface under sunlight and ultraviolet (UV) light and compared with dark condition. The half-lives of metsulfuron methyl under UV light and sunlight were found to be 0.5 and 7.8 days respectively. Rate of phototransformation followed first order kinetics with significant correlation coefficient. The major photoproducts were identified as methyl-2-sulfonyl-amino-benzoate, 2-amino-6-methoxy-4-methyltriazine and saccharin (O-sulfobenzoimide). Various metabolites from this study were identified by high performance liquid chromatography (HPLC). Authentic samples required for HPLC comparison were prepared in laboratory and characterized on the basis of nuclear magnetic resonance (NMR) and infra red (IR) spectral data. These metabolites were also identified from metsulfuron methyl treated wheat field soil. 相似文献