Contamination of pastures by polycyclic aromatic hydrocarbons (PAHs) in the vicinity of a highway   总被引：2，自引：0，他引：2  

Crépineau C  Rychen G  Feidt C  Le Roux Y  Lichtfouse E  Laurent F 《Journal of agricultural and food chemistry》2003,51(16):4841-4845

To assess PAH contamination pastures, grass and soil samples have been collected from 10 m (d1), 50 m (d2), and 150 m (d3) perpendicular to a French highway (70,000 vehicles per day) and at a control site in a rural area away from nearby contaminating sources. Total PAH concentration ranges from 767 ng/g dry weight to 3989 ng/g dry weight, according to the matrix and the distance from the highway. Distance is not a significant factor for PAH deposition on grass, while in soil it has an effect between d1 and d2 or d3. The total PAH concentration in highway samples is 8 times higher than in control site samples for grass and 7 to 4 times higher for soil. Fluoranthene, pyrene, and phenanthrene are the major PAHs in grass samples at the control site and the highway, but the concentrations are about 5 times higher near the highway. In soil samples collected near the highway, the values of concentrations between all compounds are not statistically different. PAH deposition on grass is linked to the physicochemical properties of the compounds, which lead to a specific distribution of each molecule (according to their volatility and the number of aromatic rings) while no specific behavior is revealed in soil.  相似文献   

Detection of polycyclic aromatic hydrocarbon levels in milk collected near potential contamination sources     

Grova N  Feidt C  Crépineau C  Laurent C  Lafargue PE  Hachimi A  Rychen G 《Journal of agricultural and food chemistry》2002,50(16):4640-4642

Polycyclic aromatic hydrocarbons (PAHs), mainly formed by incomplete anthropogenic organic matter combustion, are ubiquitous in the environment. To assess milk PAH contamination sources, milk samples were collected from the tank milk at farms located near potential contaminating emission sources such as cementworks, steelworks, and motorways. PAH analyses were carried out by gas chromatography coupled to mass spectrometry. Eight PAHs were identified in milk: naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, fluoranthene, pyrene, and benzo[a]anthracene. For all potential contaminating sources, these eight PAHs were detected with similar profiles and at low concentrations except for fluorene and naphthalene, for which source-molecule interaction is pointed out.  相似文献   

ToF-SIMS characterization of thermal modifications of bixin from Bixa orellana fruit     

Bittencourt C  Felicissimo MP  Pireaux JJ  Houssiau L 《Journal of agricultural and food chemistry》2005,53(16):6195-6200

Bixa orellana fruit extracts were studied by time-of-flight secondary ion mass spectrometry (ToF-SIMS). The intensity of the peak at m/z 396, assigned to the bixin molecular ion plus two hydrogen atoms (C25H(32)O(4+), decreased as the extract was heated and nearly disappeared with heating above 150 degrees C. Simultaneously, the formation of dimers at m/z 790, 804, and 818 was observed. The ToF-SIMS spectrum is characterized by a large amount of peaks generated by the principal ions and their multiple fragmentation patterns. To extract maximum information from the data set, multivariate statistical analysis was applied. Principal component analysis revealed important structural changes of the bixin molecule upon heating at different temperatures. This information can be used by the food industry as by controlling the temperature of the heating process the red/yellow balance of this colorant can be tuned.  相似文献   

The Importance of Precedent Hydro-climatological Conditions for the Mass Transfer of Pollutants in Separated Sewer Systems and Corresponding Tributaries During Storm Events     

Andreas Krein  Merce Salvia-Castellvi  Jean Francois Iffly  Laurent Pfister  Lucien Hoffmann 《Water, air, and soil pollution》2007,182(1-4):357-368

Runoff events were analysed in separated sewer systems in the town of Luxembourg. The relationships between Event Mean Concentrations of different pollutants and runoff patterns were evaluated. In addition, the inter-storm and intra-storm variability of the material transport were determined. Primarily, the variations in pollutant concentrations and loads are determined by the antecedent weather conditions. The presence of illicit sanitary inputs in one of the sewers produced a significant first flush effect as well as higher Event Mean Concentrations for pollutants. Furthermore, near the town of Trier 40 storms were analyzed in a small natural basin mainly influenced by runoff from a separated sewer system. Natural and artificial storm events were investigated in order to estimate the relationship between the pollutant sources in the channel and from the separated sewer system. Just like in the canalization of Luxembourg City the pollutant dynamics during natural storms are strongly influenced by pre-event hydrological conditions. The artificial storms behave differently. Despite little pre-rain, the maximum concentrations of toxic substances are comparatively low. A resuspension of sediment only occurs in the natural channel system, without the introduction of fines from the sewer system.  相似文献   

Fibrocartilaginous Embolism of the Spinal Cord in Dogs: Review of 36 Histologically Confirmed Cases and Retrospective Study of 26 Suspected Cases   总被引：3，自引：2，他引：1  

Laurent Cauzinille  Joe N. Kornegay 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(4):241-245

Clinical features of 36 dogs with histologically confirmed fibrocartilaginous embolism (FCE) were contrasted with those of 26 dogs in which FCE was suspected based on characteristic clinical findings and the absence of compressive spinal cord disease on myelography. Dogs with confirmed and suspected FCE were of similar signalment, and had acute, nonprogressive dysfunction, often associated with trauma or exercise. The "suspected" group included fewer giant breeds and more often had asymmetric lesions, intact nociception, and upper motor neuron involvement. Dog size and severity of clinical signs probably contributed to owners choosing euthanasia in dogs with confirmed lesions. Accordingly, data from such patients may be skewed relative to these clinical features. J Vet Intern Med 1996;10:241–245. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   

Differences between the testicular morphology of Fasciola hepatica and Fasciola gigantica     

P Bergeon  M Laurent 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1970,23(2):223-227

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Decoquinate. Estimation of residues in chicken tissues before and after cooking     

R Ferrando  M R Laurent  B L Terlain  M C Caude 《Journal of agricultural and food chemistry》1971,19(1):52-54

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Aujeszky's disease in France: isolation of the virus from 2 cats     

T Metianu  A Lucas  A Vallee  R Laurent 《Bulletin de l'Académie vétérinaire de France》1971,44(5):221-228

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Effect of osmotic pressure on the multiplication of rinderpest virus in cell culture     

P Bourdin  A Laurent 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1968,21(4):437-441

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Primary orthostatic tremor in Great Danes     

Garosi LS  Rossmeisl JH  de Lahunta A  Shelton GD  Lennox G 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):606-609

Two Great Danes were presented for an investigation of 6-month histories of incessant tremor of all 4 limbs and trunk occurring only when the dogs were standing at rest. Dog 1 was a 2-year-old intact female harlequin Great Dane living in the UK, and dog 2 was a 2-year-old castrated male fawn Great Dane living in the United States. The owners described both dogs as having constant quivering of the limbs while standing, suggestive of an involuntary dance, since the age of 18 months. The intensity of the tremors was reported in both dogs to have steadily increased since onset. In dog 1, tremors were noticed to be more pronounced in the fore limbs when she was eating and more pronounced in the hind limbs when she was trying to sit. The owner of dog 1 also reported that the dog could no longer assume a position of recumbency without manual assistance because of the severity of the tremors. Intermittently, tremors were reported to involve the facial musculature of dog 2. Vaccinations were current, and the owners of both dogs did not report any previous medical history, exposure to natural or manufactured toxins, or concurrent treatment. No familial relationship was identified between these 2 dogs.  相似文献