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51.
Sundberg H Tjärnlund U Kerman G Blomberg M Ishaq R Grunder K Hammar T Broman D Balk L 《Marine pollution bulletin》2005,50(2):195-207
For reliable monitoring of environmental improvement, the PCB contaminated bay Orserumsviken on Sweden's Baltic coast was investigated prior to remediation. We examined PCB congener patterns and the relative toxic potential of PCBs in extracts of three matrices: bottom sediment, settling particulate matter and the dissolved phase (obtained from semi-permeable membrane devices). Congener patterns were similar in all matrices. Three fractions were isolated from the extracts: (1) aliphatic and monocyclic aromatic compounds (MAC-fraction), (2) dicyclic aromatic compounds (DAC-fraction), including PCBs, and (3) polycyclic aromatic compounds (PAC-fraction), including PAHs. Total extracts and fractions were injected into newly fertilised rainbow trout eggs. At larval stage, hepatic EROD activities were quantified. Though high, the PCB contamination could explain only an estimated 1-5% of the total EROD induction. The order of EROD induction potential was: total extract > PAC-fraction > DAC-fraction > MAC-fraction in all matrices, suggesting that in Orserumsviken PACs made a larger contribution to the EROD induction potential than PCBs and other DACs. 相似文献
52.
Vernon A. Phelps Research Scientist Project Director Armin W. Troesch Assistant Research Scientist John P. Hackett Graduate Research Assistant 《Ocean Engineering》1980,7(2):281-304
Fluid-flow measuring devices intended for full scale use were designed and tested. One device consisted of a rake supporting different types of pitot tubes. This will be used to obtain a velocity profile of the boundary layer of a test ship. The other device was a five-hole pitot tube that was used in a wake survey. The pressure transport medium (i.e. the medium that carried the pressure signal from the pitot tube to the pressure transducer) was air instead of water. This proved to be successful, as the results indicate. 相似文献
53.
Anders Goksoyr Jonny Beyer Hvard E. Larsen Tommy Andersson Lars Frlin 《Marine environmental research》1992,34(1-4)
Cytochrome P450 monooxygenase activities, reflecting the expression of various subfamilies of P450, were measured in liver samples of harp and hooded seal. Differences in some of the investigated parameters were observed between the two species, between sexes, and between pups and adults. Treatment of single female pups from each species with phenobarbital (i.v. 45 mg/kg), resulted in increased levels of EROD and estradiol 2-hydroxylase activities in both species, whereas MCOD, ECOD and PROD activities were induced only in the harp seal sample. Antibodies against a dog P450 2B form (anti-dog PBD-2 IgG) gave a single band around 52kD in both species, strongest in male pups. This band seemed elevated in the PB-treated harp seal pup. Based on the single treated pup of each species, the results suggest that seals respond to PB-type treatment with a weaker response, and with different enzyme patterns, that most terrestrial mammals. Antibodies against cod P450 IAI cross-reacted with two bands in liver samples from adult seals of both species (about 54 and 52kD), but this was strongest in the hooded seal. The intensity of the bands reflected the EROD activities in the samples, suggesting the application of immunodetection in screening marine mammals for effects of environmental contamination. 相似文献
54.
An extensive trial to examine physiological and biochemical changes in perch (Perca fluviatilis) inhabiting coastal waters polluted by bleached kraft mill effluents has been carried out. The results from this investigation show profound effects of bleached kraft mill effluents on several fundamental biochemical and physiological functions on four different sampling occasions. Typical symptoms in perch from the polluted areas were reduced gonad growth, enlarged liver, and very strong induction of certain cytochrome P-450-dependent activities. Elevated content of ascorbic acid in liver tissue and strongly affected carbohydrate metabolism show that the effluent causes metabolic disorders. Marked effects on the white blood cell pattern indicate a suppressed immune defence. Alterations in the red blood cell status and the ion balance suggest an impaired gill function. This extensive symptom picture is strengthened by the relatively good agreement with the effects previously observed in fish exposed to bleached kraft mill effluents (BKME) in the laboratory.1–3 相似文献
55.
The Middle to lower Upper Devonian succession of the Rügen Depression in NE Germany consists of largely clastic sediments, whereas the Upper Devonian deposits are mixed carbonate and clastic. Petrographic and geochemical data suggest that the sediments were deposited in a cratonic or recycled setting. Deposition was largely confined to a fault-bounded basin, located between two structural highs. During the Devonian, the Rügen area underwent evolution from a continental and marginal marine area during the Eifelian-early Frasnian to a deeper marine environment during the late Frasnian-early Famennian. By the latest Famennian, an open-shelf carbonate-facies environment was established. 相似文献
56.
This study examines the labour market outcomes of the recent economic crisis ( krismon ) in Indonesia, focusing on the change of employment structure between 1997 and 1998. Indonesia's labour market has been extremely flexible in adjusting itself during the crisis. Labour has moved from "modern" economic sectors to agricultural and "informal" sectors, reflecting the strategy of poor households to cope with the hardship. While the impact of the economic crisis on the majority of male workers has been severe, female labourers have become increasingly involved in several jobs to enable the survival of their families. 相似文献
57.
When the ecological effects of the proposed Qattara Hydrosolar Power Project were investigated, a number of submarine ridges were found in Arabs Gulf, Egypt.Those ridges were of unconsolidated oolitic origin, which was of critical importance for the water intake conditions of the Qattara Project. They were scientifically extremely interesting as being the first recent oolites ever found in the Mediterranean. The ridges have been studied concerning the geology, morphology and the water dynamics both in the field and from different satellite sensors‐MSS, TM and SPOT. Satellite mapping of the structure of the ridges, benthic algae and geology has been performed. The identification of the benthic algae has been accomplished by a semi‐manual box‐classifier technique. A new accurate depth chart of Arabs Gulf has been constructed using TM data calibrated against echosoundings. By creating a synthetical digital terrain model of the bed‐rock of Arabs Gulf and comparing it with the satellite image the amount of oolitic material of the bay has been estimated. The character and location of the ridges has been compared with similar oolitic forms in the West Indies. 相似文献
58.
We develop the relational economic geographical potential of the incubator and hinge functions of megalopolis incorporating ideas from the literature on regional innovation systems and New Argonaut connections respectively. Empirically, we investigate how China’s Yangtze River Delta (YRD) has incubated but also articulated knowledge interactions at different geographical scales. Drawing upon co-patent data from the World Intellectual Property Organization database, we show that the YRD’s knowledge hinge role has strengthened over time, notably as a result of the role played by economic entities in Shanghai – the YRD’s gateway city. To unpack the YRD’s knowledge hinge role, we use information attached to co-patents to distinguish different channels – multinational enterprises, Chinese domestic enterprises, universities and research institutes, and “New Argonaut” linkages – by which YRD cities have accessed exogenous knowledge at different geographical scales. In conclusion we highlight the value of megalopolis as a meso-scale unit of analysis for relational economic geography. 相似文献
59.
Tommy G. Jensen Timothy J. Campbell Richard A. Allard Richard Justin Small Travis A. Smith 《Ocean Dynamics》2011,61(5):657-674
The coupled ocean atmosphere mesoscale prediction system that includes the Navy Coastal Ocean Model has been configured for
the Kuroshio Extension region using multiple one-way nested high-resolution grids. The coupled model system was used to simulate
a strong cold-air outbreak event from 31 Jan to 7 Feb 2005 in good agreement with meteorological data from a surface buoy
data and QuikSCAT scatterometer winds. Latent heat fluxes and sensible heat fluxes were computed during the event with daily
averages in excess of 1,500 W/m2 and 500 W/m2, respectively, and combined instantaneous turbulent heat fluxes up to 2,300 W/m2. The largest heat fluxes were found in two large meanders of the Kuroshio and along its southern flank. Strong gradients
in turbulent heat fluxes coincided with strong sea surface temperature gradients and were maintained during the cold-air outbreak
simulation. The large turbulent heat fluxes lead to significant subtropical mode water formation during the event at a rate
about 10 Sv in the cyclonic recirculation region south of the Kuroshio. This increased the volume of core layer mode water
within the temperature range 16°C to 18°C by 10% and increased the surface area of that layer directly exposed to the atmosphere
by a factor close to 5 in the model domain. 相似文献
60.