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921.
J. Z. Abrams S. J. Zaczek A. D. Benz L. Awerbuch J. Haidinger 《Journal of the Air & Waste Management Association (1995)》2013,63(7):969-974
For seasite power plants using seawater for condenser cooling, Bechtel developed a new process to remove better than 90 percent of flue gas SO2 using seawater and lime. Tests demonstrate that marine life is not affected by the effluent from this unique scrubbing process; therefore, the aqueous effluent containing reacted products (gypsum) in solution at low concentration is suitable for discharge to the sea. 相似文献
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Noninvasive prenatal testing (NIPT) has had a profound influence in the field of prenatal diagnosis since the 1997 discovery of cell-free fetal DNA in maternal blood. Research has progressed rapidly, with clinical data supporting laboratory studies showing that NIPT is highly sensitive and specific for fetal aneuploidy, resulting in marked uptake in the high-risk patient population. The superior accuracy of NIPT compared with conventional screening methods has led to significant decreases in the number of invasive diagnostic procedures, in addition to a concomitant decrease in the number of procedure-related fetal losses. Yet, NIPT has been described as a ‘disruptive innovation’ due to the considerable changes the technology has commanded on current prenatal screening and diagnostic practices. This review summarizes both institutional and global experience with NIPT uptake, its effect on reducing diagnostic invasive procedures, and the unique challenges that reduced procedural volume may have on physician and trainee proficiency, cytogenetic laboratories, and neonatal outcome. © 2015 John Wiley & Sons, Ltd. 相似文献
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Jonathan P. Park Katharine H. Barefoot Kim Ornvold Susan Z. Berg Josiane R. Dossu T. K. Mohandas 《黑龙江环境通报》2001,21(5):351-353
We report the prenatal diagnosis of a fetus with tetrasomy 5p mosaicism resulting from a supernumerary isochromosome for the short arm of chromosome 5. The pregnancy was terminated and fetal autopsy revealed minor facial abnormalities (long philtrum, up-slanting palpebral fissures and a broad nasal bridge). Cultures were established from fetal skin, kidney, and pancreas for cytogenetic analysis; the i(5p) was observed only in the skin fibroblasts. To our knowledge, this is the fourth report of mosaic tetrasomy 5p and the first report of prenatal diagnosis of this abnormality. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
927.
As with many farmland bird species, the house sparrow Passer domesticus is declining in Europe, mainly due to intensification of agriculture reducing nest sites and food supplies. During 2002–2005,
we studied the population size and nest site characteristics of house sparrows breeding within white stork Ciconia ciconia nests in a large area of agricultural landscape within western Poland. To explain sparrow density within stork nests, we
examined characteristics of white stork nests (position, age, productivity) and the farm type around the nest. House sparrow
density was greatest in the longest established (and hence larger) white stork nests located on traditionally managed farms.
Two recent changes appear to have adverse effects on house sparrows. The first is the intensification of farming and the second
is active management of white stork nests on electric poles to reduce nest size and thus avoid both disruption to the electrical
supply and electrocution of white storks. Because the white stork has such a high profile in Poland, there are numerous schemes
to conserve and enhance this species. In conclusion, we clearly show that protecting one species can have valuable, although
unplanned, benefits to another species of conservation interest, the house sparrow. 相似文献
928.
Ventura-Lima J Sandrini JZ Cravo MF Piedras FR Moraes TB Fattorini D Notti A Regoli F Geracitano LA Marins LF Monserrat JM 《Environment international》2007,33(4):559-564
Several environmental pollutants, including metals, can induce oxidative stress. So, the objective of this study was to evaluate the effects of arsenic (As(III), as As(2)O(3)) on the antioxidant responses in the polychaete Laeonereis acuta. Worms were exposed to two environmentally relevant concentrations of As, including the highest previously allowed by Brazilian legislation (50 microg As/l). A control group was kept in saline water (10 per thousand) without added metal. It was observed that: (1) a peak concentration of lipid peroxide was registered after 2 days of exposure to 50 microg As/l (61+/-3.2 nmol CHP/g wet weight) compared to the control group (43+/-4.5 nmol CHP/g wet weight), together with a lowering of the activity of the antioxidant enzyme catalase (-47 and -48%, at 50 or 500 microg As/l respectively) and a higher superoxide dismutase activity (+305% at 50 microg As/l with respect to the control group); (2) a lower conjugation capacity through glutathione-S-transferase activity was observed after 7 days of exposure to 50 microg As/l (-48% compared to the control group); (3) a significant increase in As concentration was verified after 1 week of exposure to both As concentrations (50 and 500 microg/l); (4) worms exposed to As showed a limited accumulation of related methylated As species and the levels of non-toxic As species like arsenobetaine (AsB) and arsenocholine (AsC) remained unchanged during the exposure period when compared with the controls. Overall, it can be concluded that As interfered in the antioxidant defense system of L. acuta, even at low concentrations (50 microg/l) that Brazilian legislation previously considered safe. The fact that worms exposed to As showed high levels of methylated As species indicates the methylation capability of L. acuta, although the high levels of inorganic As suggest that not all the administered As(III) (as As(2)O(3)) is completely removed or biotransformed after 7 days of exposure. 相似文献
929.
To compare the zooplankton communities in the South Branch, North Branch, North Channel and offshore of the Changjiang (Yangtze River) estuary, two cruises were carried out in the autumn of 2009 and the spring of 2010. A total of 27 species of zooplankton were identified in the spring, including 17 in the offshore, 11 in the south branch, 9 in the north branch, and only 5 in the North Channel. In autumn, altogether 71 species were collected, including 6 in the south branch, 11 in the north branch, 8 species in the North Channel area and 63 in the offshore. Either in the spring or autumn, the average species numbers of the offshore were the highest. Additionally, species numbers of the offshore were significantly higher than that in other areas (P < 0.05) for both seasons. There were no significant differences between the species number of the South Branch and the North Branch (P > 0.05). The species number and diversity index of the inner area were lower than that of the offshore. The average diversity index of offshore area was still the highest in both spring (1.69) and autumn (3.73). In spring, the diversity index of the North Channel was the lowest among four areas, while in autumn, that of the South Branch was the lowest (0.49). In spring, Sinocalanus sinensis was the dominant species of the South Branch, North'Branch and North Channel (> 50% of the total collection by number). The dominant species of offshore area were Tortanus vermiculus and Labidocera euchaeta. While in autumn, the dominant species were different for each area. In the South Branch, the most important species was S. dorrii (93.55% of the total collection by number). The main species was S. dorrii in the South Branch area, S. stenellus and T. vermiculusin in the North Branch and Subeucalanus subcrassus in the offshore (< 30% of the total collection by number). Numbers of species and diversity index seemed to vary among different areas of Changjiang estuary. The underline mechanisms of the regional variation in species number were mainly the salinity and suspended sediment concentrations. Generally speaking, zooplankton was more abundant in the polyhaline water. Diversity index was largely affected by both species number and abundance percentage. The zooplankton community was mainly influenced by the Changjiang diluted water and offshore water mass through affecting the salinity. In autumn, the Kuroshio flowed northward carrying polyhaline water, and brought subtropical species to the offshore of the Changjiang estuary. Since the North Channel is located in the estuarine turbidity zone, suspended sediment concentration of that area is higher than the other areas, which might limit the distribution of some species. To sum up, salinity is the most important factor causing the difference of zooplankton community among different areas in the Changjiang estuary. Besides, water masses and estuarine turbidity also influence the zooplankton community. 相似文献
930.
L. El Fels F.Z. El Ouaqoudi L. Lemee P. Winterton G. Merlina Y. Ouhdouch 《Chemistry and Ecology》2013,29(1):64-76
The fatty acids of two composts of active sludge with palm tree waste were investigated by thermochemolysis coupled to gas chromatography-mass spectrometry. This method (tetramethylammonium hydroxide-pyrolysis-gas chromatography-mass spectrometry) allowed the direct determination of total fatty acids (analysed as fatty acid methyl esters: FAMEs) present in the organic matter of the samples without any separation procedures. Mixture A was 1/3 sludge+2/3 palm waste and mixture B was 1/2 sludge+1/2 palm waste. The level of FAMEs rose by 8.4–33.3% and 10.8–13.4% in mixtures A and B, respectively, after 6 months of co-composting. Branched FAMEs of bacterial origin (iC15:0) rose during the thermophilic phase, in mixture A the aC17:0/aC15:0 ratio increased during the co-composting process, also in mixture B the aC16:0/C16:0 ratio rose but only during the thermophilic phase. All the FAMEs identified showed a drop at the end of co-composting except for C18:0 and C16:0. The stabilisation phase was characterised by a significant rise in the length of the aliphatic chains; the carbon preference index thus increased at the end of the composting process, indicating that the final product was proportionally richer in fatty acids of plant origin. 相似文献