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101.
Hartmut Koehler Tobias Frische Ingo Dobner Peter Behrend Maike Schaefer Heidi Taubner Bernd Jastorff Jürgen Warrelmann und Ulrich Walter 《Umweltwissenschaften und Schadstoff-Forschung》2001,13(5):291-300
Zusammenfassung Die Befunde des in seiner Konzeption in Teil I dargestellten Freilandexperimentes dokumentieren die TNT-Abreicherung und Erholung
des Standortes im Laufe der Phytoremediation. Das Monitoring umfasst Erhebungen im Feld (Nitroaromatengehalte in Boden, Sickerwasser
und Pflanzen; Erfassung von Bodenorganismen und Streuabbau) und den Einsatz einer Biotestbatterie mit 6 Einzeltests. Die Daten
belegen die hohe Heterogenit?t der TNT-Kontamination, eine rasche initiale Abreicherung und eine geringe Verlagerung von Nitroaromaten
in Pflanzen und Sickerwasser. Die anf?nglich rasche Transformation des TNT zu Aminodinitrotoluolen l?sst nach 3 Monaten deutlich
nach. Mit Hilfe der Biotestbatterie wird die Toxizit?t des Bodens differenziert beurteilbar; die boden-biologischen Befunde
lassen Langzeitwirkungen der TNT-Belastung wahrscheinlich werden. Eine Gesamtbeurteilung des Projekts wird im dritten Teil
der Artikelserie erfolgen.
OnlineFirst: 10. 09. 2001 相似文献
102.
Tuan Xu Heidi Q. Xie Yunping Li Yingjie Xi Rui Sh Lingyun Wang Yangsheng Chen Li Xu Bin Zhao 《环境科学学报(英文版)》2018,30(1):260-267
Dioxin can cause a series of neural toxicological effects. Micro RNAs(mi Rs) play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-mi R-146 b-5 p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-mi R-146 b-5 p. We found that the hsa-mi R-146 b-5 p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-mi R-146 b-5 p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-mi R-146 b-5 p significantly suppressed acetylcholinesterase(ACh E) activity and targeted the3′-untranslated region of the ACh E T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-mi R-146 b-5 p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which ACh E may serve as a responsive gene for mediating the effect. 相似文献
103.
Lipid composition and partitioning of deepwater chondrichthyans: inferences of feeding ecology and distribution 总被引:1,自引:1,他引:0
The composition of lipids and fatty acids was determined for the livers, muscle, pancreas, kidney and stomach fluids of deepwater
chondrichthyan species (including 11 squaliformes, 3 chimaeriformes, 1 hexanchiforme and 3 carcharhiniformes) caught as bycatch
from continental waters off south-eastern Australia. The lipid class, fatty acid and fatty alcohol composition differed markedly
in each tissue and in each species. The lipid and fatty acid composition of large, lipid-rich (38–70% wet weight, ww) livers
demonstrated the multifunctional role of this organ in: lipid distribution, storage and biosynthesis, and buoyancy regulation.
In the liver, the importance of certain lipids (including squalene, diacylglyceryl ethers, triacylglycerols and to a lesser
extent wax esters) as mediators of buoyancy varied according to lifestyle and habitat. Less variability was observed in the
muscle profiles, characterized by low lipid content (<1.0% ww) and high relative levels of polar lipids (>70%). The lipid
and fatty acid profiles of the kidney and pancreas showed the highest intraspecific variability, suggesting these organs also
have complex roles in lipid storage and metabolism. Overall intra- and interspecific differences in the tissue fatty acid
profiles could be related to differences in a number of factors including phylogeny, habitat (depth), buoyancy regulation
and diet and presumably also reflect different ecological roles. The lipid and fatty acid profiles are the first published
for Rhinochimaera pacifica, Chimaera lignaria and Figaro boardmani and the first to demonstrate interspecific variation in lipid profiles of various tissues of deepwater chondrichthyans. The
application of multivariate analysis to lipid class and fatty acid tissue profiles in chondrichthyans inferred dietary differences
and metabolic preferences between species and habitats. These results have important implications for the future use of fatty
acids as dietary tracers in chondrichthyan research. 相似文献
104.
Movements and site fidelity of the giant manta ray, <Emphasis Type="Italic">Manta birostris,</Emphasis> in the Komodo Marine Park,Indonesia 总被引:2,自引:1,他引:1
Heidi Dewar Peter Mous Michael Domeier Andreas Muljadi Jos Pet Jeff Whitty 《Marine Biology》2008,155(2):121-133
Despite their large size and frequent occurrence in near-shore tropical habitats, little published information is available
on the movements and behaviors of the giant manta ray, Manta birostris, and what factors influence visitation patterns. To examine the movements of manta rays in the Komodo Marine Park, Indonesia,
an acoustic array was installed at up to seven sites in the park between 2000 and 2003. A total of 41 acoustic tags were deployed
in three separate deployments in 2000, 2001 and 2002. Mantas were recorded in the park for up to 526 days with an average
duration of 183 ± 136 days, when mantas made from 3 to 303 individual visits to different sites (median 58 visits). There
was a clear preference for three sites that comprised over 90% of manta activity. The most popular site (German Flag) was
off the southern tip of Komodo Island in an area with a high degree of bathymetric structure. Examination of the longest records
suggests some site preference with 5 of 7 individuals spending greater than 90% of their time at the location where they were
tagged. Using a general linear model it was possible to examine the effects of daytime, lunar phase, aggregation site, season
and tidal phase on visitation patterns. The vast majority of visits were recorded during daylight hours at all sites. The
strongest effects of both the lunar and tidal phase were apparent in the northern sites with the most visits occurring when
tidal intensity was the greatest during full and new moons. The strongest seasonal pattern was observed in the south where
no mantas were recorded during the first quarter in any year. This coincides with an increase in temperature and reduction
of productivity in this region associated with monsoonal shifts. The long-term fidelity indicates that marine-protected areas
centered around aggregation sites could help protect this species from overexploitation. 相似文献
105.
Heidi Van den Broeck Karin Breugelmans Hans De Wolf Thierry Backeljau 《Marine Biology》2008,153(3):421-429
Planktonic developing organisms are generally assumed to be good dispersers showing little genetic structuring in neutral
markers. At first glance, this also applies to the planktonic developing periwinkle Tectarius striatus, an endemic gastropod from Macaronesia (i.e. Azores, Madeira, Canary Islands and Cape Verde Islands), where the only sign
of genetic structuring hitherto is provided by a non-significant allozyme/RAPD heterogeneity between the Cape Verde Islands
and the other archipelagos. However, partial sequences of the mitochondrial cytochrome b and cytochrome oxidase I genes now show that the Cape Verde Islands and the three other archipelagos have no haplotypes in
common, whereas the latter three do share several haplotypes. Nevertheless, this highly disjunct haplotype distribution does
not entail a phylogeographic break separating the haplotypes of both areas in two reciprocally monophyletic groups. This remarkable
geographic and phylogenetic structuring may be explained by assuming that T. striatus colonized the Macaronesian archipelagos in periods when sea levels were lower (and/or volcanic activity was higher), so that
seamounts peaked above sea level and could act as stepping-stones. Yet, after the last glacial period seamounts submerged,
thus preventing further stepping-stones mediated dispersal of T. striatus between the Cape Verde Islands and the other archipelagos, while not affecting dispersal among the latter because of their
closer proximity and connectivity. Hence, these contrasting patterns of neutral genetic variation in T. striatus show that genetic structuring in planktonic developing species may be far more complex than is usually assumed. 相似文献
106.
This paper summarizes recent advances in vegetation hydrodynamics and uses the new concepts to explore not only how vegetation impacts flow and transport, but also how flow feedbacks can influence vegetation spatial structure. Sparse and dense submerged canopies are defined based on the relative contribution of turbulent stress and canopy drag to the momentum balance. In sparse canopies turbulent stress remains elevated within the canopy and suspended sediment concentration is comparable to that in unvegetated regions. In dense canopies turbulent stress is reduced by canopy drag and suspended sediment concentration is also reduced. Further, for dense canopies, the length-scale of turbulence penetration into the canopy, δ e , is shown to predict both the roughness height and the displacement height of the overflow profile. In a second case study, the relation between flow speed and spatial structure of a seagrass meadow gives insight into the stability of different spatial structures, defined by the area fraction covered by vegetation. In the last case study, a momentum balance suggests that in natural channels the total resistance is set predominantly by the area fraction occupied by vegetation, called the blockage factor, with little direct dependence on the specific canopy morphology. 相似文献
107.
Heidi S. Brothers 《Journal of the Air & Waste Management Association (1995)》2013,63(4):468-480
ABSTRACT An alternate compliance strategy (ACS) is developed which incorporates pollution prevention and flexibility to replace traditional end-of-pipe (EOP) control strategy regulation. The ACS takes into consideration the intent of the 1990 Clean Air Act Amendments (CAAA) to incorporate pollution prevention into regulations and provides a viable mechanism for implementation. This proposed new compliance strategy was developed after studying the CAAA regulations, related compliance issues, and pollution prevention literature. The ACS is defined by amending language in the Hazardous Organic National Emission Standards for Hazardous Air Pollutants (HON) regulation into a performance-based standard permitting regulated facilities to design compliance programs to meet all requirements. A change in regulation is considered reasonable only if it forces the same emission reductions, reduces risk a comparable amount, and is acceptable to the public, the regulators, and the regulated industry. In order to demonstrate that the ACS can meet all these requirements, an example application is summarized from an ethylene oxide-ethylene glycol plant. The example demonstrates that the ACS reduces hazardous air pollution (HAP) emissions more than the HON rule requires. Three evaluation methods are developed and applied to further demonstrate the acceptability of the ACS. They include a qualitative evaluation matrix, a total cost assessment, and a risk reduction measurement model. Results indicate that the ACS provided a preferable compliance program. The ACS should be adopted as an alternative method of compliance. It provides a major step in the progression of regulations from the traditional EOP treatment philosophy to pollution prevention performance-based standards. 相似文献
108.
Hexabromocyclododecanes (HBCDs) are persistent organic pollutants now ubiquitous in the environment. Technical HBCD mixtures and with it flame-proofed polystyrenes (FP-PS) also contain isobutoxypentabromocyclododecanes (iBPBCDs) as minor constituents, which are possibly released together with HBCDs. So far, eight diastereomeric pairs of enantiomers named as α-, β-, γ-, δ-, ?-, ξ-, η-, and θ-iBPBCDs with proportions of 10%, 5%, 2%, 21%, 11%, 11%, 12% and 28% were found in technical HBCD. Herein the crystal structure of racemic δ-iBPBCD, the second most prominent diastereomer, is presented and assigned to (1S)-1-isobutoxy-(2R,5R,6S,9S,10S)-2,5,6,9,10-pentabromocyclododecane and its enantiomer. During thermal treatment of FP-PS, e.g. the production of extruded polystyrenes (XPS), proportions of δ-iBPBCDs decrease and those of other stereoisomers increase. Evidence was found that δ-iBPBCDs isomerize stereo- and regioselectively to β-iBPBCDs. Based on structural and kinetic data, a transformation mechanism was proposed. Apparent first-order rate constants (kiso) of 0.0019, 0.0050, and 0.012 min−1 are found for the δ- to β-iBPBCD isomerization at 120, 130, and 140 °C, respectively, corresponding to half-lives of 360, 140, and 56 min. These transformations also occur during the production of XPS, which predominantly contain β-iBPBCDs, whereas δ-iBPBCDs dominate in materials experiencing lower thermal stress, e.g. expanded polystyrenes (EPS). The relative configurations of δ- and θ-iBPBCDs are TtCtCt, like the one of γ-HBCDs. γ-HBCDs are the kinetically and α-HBCDs with a TcCtCc configuration the thermodynamically favored products. In analogy, β-iBPBCDs are assumed to have a TcCtCc configuration like α-HBCDs because they are formed from δ-iBPBCDs under thermodynamic control. In conclusion, HBCD- and iBPBCD-patterns in flame-proofed polystyrenes vary substantially, reflecting the thermal stress these materials have experienced. When released to the environment, these patterns might further change, as observed for HBCDs. 相似文献
109.
Heidi Knutsen Martin Wiech Arne Duinker Amund Maage 《Environmental monitoring and assessment》2018,190(4):253
Previously, high concentrations of cadmium have been found in the hepatopancreas of the edible or brown crab (Cancer pagurus) sampled from positions north of about 67° N, compared to regions further south along the Norwegian coast, with no clear understanding why. In order to study a similar organism in the same ecosystem, the present study analyzed 210 shore crabs (Carcinus maenas) from four different locations along the Norwegian coast, two in the North and two in the South. The physiological variables size, sex, molting stage, hepatosomatic index, carapace color, and gonad maturation were registered, in attempt to explain the high inter-individual variation in cadmium levels in hepatopancreas. In contrast to the brown crabs, the shore crabs showed no clear geographical differences in cadmium concentrations. This indicates physiological differences between the two crab species. No clear and consistent correlations were found between cadmium levels and physiological parameters, except for sex, where cadmium concentration in hepatopancreas was twice as high in males compared to females. The cadmium levels also varied with season, with approximately 40 and 60% lower cadmium concentration in April than August for male and female shore crabs, respectively. None of the analyzed cadmium concentrations in muscle meat from claws exceeded EUs food safety limit, and low cadmium levels in soup prepared from shore crabs clearly indicated that this dish is not problematic regarding food safety. 相似文献
110.
Patricia Bradley William S. Fisher Heidi Bell Wayne Davis Valerie Chan Charles LoBue Wendy Wiltse 《Environmental monitoring and assessment》2009,150(1-4):43-51
Coral reefs worldwide are declining at an alarming rate and are under continuous threat from both natural and anthropogenic environmental stressors. Warmer sea temperatures attributed to global climate change and numerous human activities at local scales place these valuable ecosystems at risk. Reefs provide numerous services, including shoreline protection, fishing, tourism and biological diversity, which are lost through physical damage, overfishing, and pollution. Pollution can be controlled under provisions of the Clean Water Act, but these options have not been fully employed to protect coral reefs. No U.S. jurisdiction has implemented coral reef biocriteria, which are narrative or quantitative water quality standards based on the condition of a biological resource or assemblage. The President’s Ocean Action Plan directs the U.S. Environmental Protection Agency (EPA) to develop biological assessment methods and biological criteria for evaluating and maintaining the health of coral reef ecosystems. EPA has formed the Coral Reef Biocriteria Working Group (CRBWG) to foster development of coral reef biocriteria through focused research, evaluation and communication among Agency partners and U.S. jurisdictions. Ongoing CRBWG activities include development and evaluation of a rapid bioassessment protocol for application in biocriteria programs; development of a survey design and monitoring strategy for the U.S. Virgin Islands; comprehensive reviews of biocriteria approaches proposed by states and territories; and assembly of data from a variety of monitoring programs for additional metrics. Guidance documents are being prepared to assist U.S. jurisdictions in reaching protective and defensible biocriteria. 相似文献