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961.
962.
More than 10 years after a chromosomal anomaly screening programme was set up in France for pregnant women of advanced age, amniocentesis is still a controversial issue. The reasons why eligible women did not utilize the test and whether or not the existence of social welfare coverage determined women's access to prenatal diagnosis were studied. A group of 291 women aged ⩾35 years who recently gave birth to normal liveborns was interviewed by telephone. Among those aged 38 years and over, who automatically qualified for social security coverage, 75 per cent had undergone amniocentesis as opposed to 23 per cent in the 35 to 37-year-old non-covered age group who did not qualify for social security coverage. In both groups, access to amniocentesis was found to depend on the physicians', women's and male partners' attitudes towards prenatal diagnosis and abortion. Among the younger group, the uptake depended mainly on socio-economic factors. Institutional policies should ensure greater equality of access while allowing for individual preferences.  相似文献   
963.
964.
Enough advances have recently been made in income accounting theory to recommend that environmental services accruing either to the forest owner or to the general public should be included in the forest accounting system. In this study, the results of two case studies, one in Bonifatu, Corsica (France) and the other in Alcornocales, Andalusia (Spain), show that private environmental services provide the majority share of social total sustainable income in Alcornocales (29%), whereas public environmental services are the most relevant in Bonifatu (32%). The social total sustainable income measured by the agroforestry accounting system is, respectively, 1.6 and 2.4 times higher than the income estimated by economic accounts for forestry in Alcornocales and Bonifatu forests.  相似文献   
965.
The removal of 2,4-D (2,4-dichlorophenoxyacetic acid) from aqueous solutions by activated spent bleaching earths (SBE) was studied at 20 degrees C. Experiments were performed as a function of time, initial concentration, dose and particle size of the adsorbent. The Langmuir and Freundlich adsorption equations were fitted by the adsorption data obtained. The values of Langmuir and Freundlich constants were determined. The adsorption kinetic was found to follow Lagergren equation. Both the boundary layer and intraparticle diffusion played important roles in the adsorption rate of 2,4-D. As the size of the adsorbent increased, the time to reach equilibrium increased but adsorption capacity decreased.  相似文献   
966.
Carotenoid pigments produce yellow, orange, and red integumentary color displays that can serve as reliable signals of health and condition. In many birds and fish, individuals gain competitive or mating advantages by ingesting and utilizing large quantities of carotenoid pigments. Carotenoid pigments serve as antioxidants, performing important functions as free-radical scavengers. The beneficial effects of carotenoid pigments are well documented, but rarely have researchers considered potential detrimental effects of high-level accumulation of carotenoids. We maintained American goldfinches (Carduelis tristis) on high- or low-carotenoid diets through molt and tested for damage to the liver and skeletal muscle. High intake of carotenoids had no measurable effect on liver enzymes but caused an increase in creatine kinase, an indicator of skeletal muscle breakdown, and a reduction in vertical flight performance, a measure of skeletal muscle integrity. The detrimental effects of high-level carotenoid accumulation were approximately equivalent to the negative effects of removing carotenoids from the diet. The adverse effects observed in this study have important implications for theories of the function and evolution of colorful plumage.  相似文献   
967.
Food and Environmental Virology - This study assessed the sources of contamination of water matrices in a rural area using detection of a host-specific virus (human adenovirus [HAdV], porcine...  相似文献   
968.
969.
Wind flow and turbulence within the urban canopy layer can influence the heating and ventilation of buildings, affecting the health and comfort of pedestrians, commuters and building occupants. In addition, the predictive capability of pollutant dispersion models is heavily dependent on wind flow models. For that reason, well-validated microscale models are needed for the simulation of wind fields within built-up urban microenvironments. To address this need, an inter-comparison study of several such models was carried out within the European research network ATREUS. This work was conducted as part of an evaluation study for microscale numerical models, so they could be further implemented to provide reliable wind fields for building energy simulation and pollutant dispersion codes. Four computational fluid dynamics (CFD) models (CHENSI, MIMO, VADIS and FLUENT) were applied to reduced-scale single-block buildings, for which quality-assured and fully documented experimental data were obtained. Simulated wind and turbulence fields around two surface-mounted cubes of different dimensions and wall roughness were compared against experimental data produced in the wind tunnels of the Meteorological Institute of Hamburg University under different inflow and boundary conditions. The models reproduced reasonably well the general flow patterns around the single-block buildings, although over-predictions of the turbulent kinetic energy were observed near stagnation points in the upwind impingement region. Certain discrepancies between the CFD models were also identified and interpreted. Finally, some general recommendations for CFD model evaluation and use in environmental applications are presented.  相似文献   
970.
Antimicrobial resistance and the mechanisms implicated were studied in 54 enterococci recovered from 57 seagull fecal samples. Almost 78% of the recovered enterococci showed resistance against one or more antibiotics and these isolates were identified to the species level. E. faecium was the most prevalent species (52.4%). High percentages of erythromycin and tetracycline resistances were found among our isolates (95.2%), and lower percentages were identified to other antibiotics. Most of the tetracycline-resistant strains carried the tet(M) and/or tet(L) genes. Genes associated with Tn916/Tn1545 and/or Tn5397 transposons were detected in 45% of tetracycline-resistant isolates. The erm(B) gene was detected in 65% of erythromycin-resistant isolates. The vat(D) and vat(E) genes were present in 5.9% and 11.8% of quinupristin/dalfopristin-resistant isolates, respectively. The ant(6)-Ia gene was identified in 57.1% of streptomycin-resistant isolates. All nine kanamycin-resistant isolates carried the aph(3)'-IIIa gene. The cat(A) gene was found in two chloramphenicol-resistant isolates. Seagulls should be considered a risk species for spreading in the environment antimicrobial resistant enterococci and can serve as a sentinel for antibiotic pressure from the surrounding farm and urban setting.  相似文献   
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