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91.
Atlantic salmon (Salmon salar) populations from four locations, two from isolated Swedish lake systems, one of the Baltic Sea and one of the North Atlantic, were analyzed to determine the concentrations and spatial variations of polybrominated diphenyl ethers (PBDEs) and organochlorines (DDT, PCB and HCH). Levels in both liver and muscle were in the same range as previously reported in Atlantic salmon, except for elevated concentrations found per lipid weight (lw) in the muscle samples of salmon from the North Atlantic ( summation PBDE 263 ng g(-1) lw, summation PCB 3262 ng g(-1) lw, summation DDT 4063 ng g(-1) lw summation HCH 131 ng g(-1)). In general, elevated concentrations in the muscles compared to the liver were observed, especially in lipid depleted migrating salmon, possibly caused by a faster lipid depletion compared with the redistribution of PBDEs, PCBs and DDTs. These findings indicated that the life stage and thereby the lipid dynamics of the fish must be considered prior to comparison based on lipid weight, especially as Atlantic salmon experience large variations in lipid content during periods of migration. The dominating PBDE congener was BDE-47, representing more than 25% in all fish. The PBDE pattern changed between locations, with a significant separation of the fish from the freshwater and marine environment when analyzed using principal component analysis.  相似文献   
92.
A microplate method was developed as a tool to test phages for their ability to control Salmonella in aqueous environments. The method used EPA (U.S. Environmental Protection Agency) worst case water (WCW) in 96-well plates. The WCW provided a consistent and relatively simple defined turbid aqueous matrix, high in total organic carbon (TOC) and total dissolved salts (TDS), to simulate swine lagoon effluent, without the inconvenience of malodor and confounding effects from other biological factors. The WCW was originally defined to simulate high turbidity and organic matter in water for testing point-of-use filtration devices. Use of WCW to simulate lagoon effluent for phage testing is a new and innovative application of this matrix. Control of physical and chemical parameters (TOC, TDS, turbidity, temperature, and pH) allowed precise evaluation of microbiological parameters (Salmonella and phages). In a typical application, wells containing WCW were loaded with Salmonella enterica susp. enterica serovar Typhimurium (ATCC14028) and treated with phages alone and in cocktail combinations. Mean Salmonella inactivation rates (k, where the lower the value, the greater the inactivation) of phage treatments ranged from -0.32 to -1.60 versus -0.004 for Salmonella controls. Mean log(10) reductions (the lower the value, the greater the reduction) of Salmonella phage treatments were -1.60 for phage PR04-1, -2.14 for phage PR37-96, and -2.14 for both phages in a sequential cocktail, versus -0.08 for Salmonella controls. The WCW microcosm system was an effective tool for evaluating the biocontrol potential of Salmonella phages.  相似文献   
93.
In a 1981 survey of 436 Florida citrus growers, 27 pesticide related poisoning incidents were reported that were to have taken place within one year of the interview date. From these reports it is possible to estimate that there are 376 citrus fieldworker related poisonings per year in Florida. This number of estimated poisonings may be developed into an incidence rate of 113 fieldworker poisonings per 10,000 fieldworkers.  相似文献   
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When combined in the lining and covering of waste-containment facilities, soil and geosynthetic components protect the environment by acting as a hydraulic barrier. Equipment loading may significantly increase the tensile stress induced in geosynthetic components, leading to a potential stability problem. Large equipment loadings may also result in a localized circular slip surface during construction operations. New analytical method based on discrete element modelling is proposed for estimating the distribution of tensile force developed in the individual geosynthetic components of the lining system and for evaluating the safety factor of slope failure due to equipment loading. The analytical results of an example are presented to demonstrate the applicability of the analytical method for the lining system of a waste landfill. The analyses of the example show that equipment loading provide a substantial increase in the tensile forces of the geosynthetic components of a lining system and that the possibility of shallow failure due to equipment loading increases as the slope becomes steeper. This method is a useful tool for analysing the lining system of waste landfills with complex lining components.  相似文献   
96.
5p deletion syndrome commonly known as cri du chat is well described in affected neonates with catlike cry and hypotonia. Karyotyping will usually show a deletion of the short arm of one chromosome 5 with variable breakpoints. Only a few cases have been reported prenatally, and the fetal form of the syndrome has not been clearly individualised. We report a new case of 5p deletion syndrome diagnosed prenatally in association with Dandy–Walker syndrome and agenesis of the corpus callosum. Other brain anomalies have been reported previously, but this unusual association suggests the use of a specific probe in the investigation of these malformations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
97.
Prader–Willi syndrome (PWS) results from either paternal deletion of 15q11–q13, or maternal uniparental disomy (UPD) of chromosome 15 or imprinting center mutation. Prenatal diagnosis of PWS is currently indicated for chromosomal parental translocation involving chromosome 15 and for decreased fetal movements during the third trimester of gestation. Here we present the prenatal diagnosis of PWS during the first trimester of gestation and autopsy findings. Chorionic villus sampling (CVS) was performed for advanced maternal age at 13 weeks' gestation. CVS showed mosaicism including cells with a normal karyotype and cells with trisomy 15. Amniocentesis showed cells with a normal karyotype. Molecular analysis demonstrated that the fetus had a typical PWS abnormal methylation profile and maternal disomy for chromosome 15. Fetal ultrasound examination showed slightly enlarged lateral ventricles and hypoplasic male external genitalia without intra-uterine growth retardation. The autopsy showed a eutrophic male fetus with facial dysmorphy, hypoplasic genitalia, abnormal position of both feet and posterior hypoplasia of the corpus callosum. This report points out that in a karyotypically normal fetus with ambiguous male external genitalia and cerebral anomalies, extensive cytogenetic and molecular biology studies are strongly recommended because of risk of PWS. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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Earthquake hazard assessment after Mexico (1985)   总被引:1,自引:0,他引:1  
Degg MR 《Disasters》1989,13(3):237-246
The 1985 Mexican earthquake ranks foremost amongst the major earthquake disasters of the twentieth century. One of the few positive aspects of the disaster is that it provided massive quantities of data that would otherwise have been unobtainable. Every opportunity should be taken to incorporate the findings from these data in earthquake hazard assessments. The purpose of this paper is to provide a succinct summary of some of the more important lessons from Mexico. It stems from detailed field investigations, and subsequent analyses, conducted by the author on the behalf of reinsurance companies.  相似文献   
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