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941.
942.
In order to evaluate the potential harmful effects of gas flaring on mammals, albino mice, Mus musculus, were exposed to gas flares for 8 weeks under laboratory conditions. The effect of gas flaring on blood parameters includes a reduction in white blood cell counts among mice exposed to 8-h daily of gas flaring when compared to control mice. The red blood cells also showed varied abnormalities such as stacked erythrocytes (rouleaux formation), crenated (spicule) cells and teardrop cells (dacrocytes). The detection of the increasing level of eosinophils in the blood of mice exposed to gas flares was observed to be indicative of a degenerative disease condition and usefulness as a good marker of pollution for monitoring, and early detection of adverse effects of gas flares was recommended. Histopathological examination of the lungs of exposed mice revealed distortions in the segmental bronchus and alveoli of the respiratory organ, with interspersed brown pigments and polymorphonuclear cells, which were absent in the controls. The environmental implications including the health hazards posed by the exposure of mammals to gas flares in crude oil production areas were discussed.  相似文献   
943.
Due to its compatibility with the current energy infrastructures and the potential to reduce CO2 emissions significantly, CO2 capture and geological storage is recognised as one of the main options in the portfolio of greenhouse gas mitigation technologies being developed worldwide. The CO2 capture technologies offer a number of alternatives, which involve different energy consumption rates and subsequent environmental impacts. While the main objective of this technology is to minimise the atmospheric greenhouse gas emissions, it is also important to ensure that CO2 capture and storage does not aggravate other environmental concerns. This requires a holistic and system-wide environmental assessment rather than focusing on the greenhouse gases only. Life Cycle Assessment meets this criteria as it not only tracks energy and non-energy-related greenhouse gas releases but also tracks various other environmental releases, such as solid wastes, toxic substances and common air pollutants, as well as the consumption of other resources, such as water, minerals and land use. This paper presents the principles of the CO2 capture and storage LCA model developed at Imperial College and uses the pulverised coal post-combustion capture example to demonstrate the methodology in detail. At first, the LCA models developed for the coal combustion system and the chemical absorption CO2 capture system are presented together with examples of relevant model applications. Next, the two models are applied to a plant with post-combustion CO2 capture, in order to compare the life cycle environmental performance of systems with and without CO2 capture. The LCA results for the alternative post-combustion CO2 capture methods (including MEA, K+/PZ, and KS-1) have shown that, compared to plants without capture, the alternative CO2 capture methods can achieve approximately 80% reduction in global warming potential without a significant increase in other life cycle impact categories. The results have also shown that, of all the solvent options modelled, KS-1 performed the best in most impact categories.  相似文献   
944.
945.
Age dependency of [3H]-ouabain binding, 45Ca2+ eflux and its magnetosensitivity in rats’ brain cortex and heart muscle tissues were studied. Curves of dose-dependent [3H]-ouabain binding consisted of three components with different affinities (10−7–10−4 M (α1); 10−9–10−7 M (α2); and 10−11–10−9 M (α3)). These curves were also characterized by different dose-dependent kinetics. [3H]-ouabain binding with α3 receptors in brain cortex and heart muscle tissues of young and adult animals had a dose-dependent character, while that in old ones had a dose-independent character. A 0.2 T static magnetic field (SMF) exposure had modulation effect on ouabain binding with α1, α2 and α3 receptors in young rats, while in adult ones, only α3 receptors were magnetosensitive. In old animals, SMF exposure had no significant effect on ouabain binding with α3 receptors in brain cortex, while in heart muscle, it had inhibitory effect on it. Age-dependent effect of ouabain impact on 45Ca2+ efflux showed that all concentrations of ouabain lead to inhibitory effect in young animals’ brain cortex and heart muscle (with the exception of 10−10 and 10−6 M), while in old ones, it had activation effect as compared with data received without ouabain. SMF exposure in young animals had activation effect on 45Ca2+ efflux from brain cortex and heart muscle in data without ouabain, and in old rats, 45Ca2+ efflux from brain cortex was magnetic insensitive. In old animals, SMF increased 45Ca2+ efflux even after extra low concentration of ouabain. It is suggested that α3 receptors having a crucial role in the regulation of Na+/Ca2+ exchange serve as age-dependent magnetosensors of excitable cells.  相似文献   
946.
Independent teams undertook environmental monitoring of particular concentrations of major construction projects forming part of Hong Kong’s U.S. $20 billion airport infrastructure programme located in dense urban areas. The team combination of environmental specialists with experienced civil engineers enabled pragmatic mitigation measures to be developed and accepted by the construction personnel with the result that potentially significant adverse impacts were averted. The authors discuss the mechanism and success of this innovative approach.  相似文献   
947.
948.
Even though the neurofibromatosis type 1 (NF1) gene was cloned more than 3 years ago, the process of identifying mutations has not been fruitful, and genetic counselling is mainly based on the use of linked markers. Since 1990, we have analysed 130 NF1 families and have performed six prenatal diagnoses. In each case, genetic counselling has relied on linked markers and informativity was achieved in all of them. The use of intragenic microsatellite polymorphisms (IVS27AAAT2.1, IVS27AC28.4, IVS27AC33.1, and IVS38GT53.0) has increased the informativeness in our series of NF1 families to an average of 90 per cent, providing accurate diagnosis and confirmation of the disease status.  相似文献   
949.
This study investigated the level of norovirus contamination in oysters collected at a lagoon receiving urban drainage from Hue City for 17 months (August 2015–December 2016). We also investigated the genetic diversity of norovirus GI and GII in oyster and wastewater samples by using pyrosequencing to evaluate the effect of urban drainage on norovirus contamination of oysters. A total of 34 oyster samples were collected at two sampling sites (stations A and B) in a lagoon. Norovirus GI was more frequently detected than GII (positive rate 79 vs. 41%). Maximum concentrations of GI and GII were 2.4 × 105 and 2.3 × 104 copies/g, respectively. Co-contamination with GI and GII was observed in 35% of samples. Norovirus GII concentration was higher at station A in the flood season than in the dry season (P = 0.04, Wilcoxon signed-rank test). Six genotypes (GI.2, GI.3, GI.5, GII.2, GII.3, and GII.4) were identified in both wastewater and oyster samples, and genetically similar or identical sequences were obtained from the two types of samples. These observations suggest that urban drainage and seasonal flooding contribute to norovirus contamination of oysters in the study area.  相似文献   
950.
We report a series of 350 patients submitted to transabdominal chorionic villus sampling (CVS). A technique using two ultrasound-guided needles and a suction pump was used. In most cases, the procedure was performed between 9 and 13 weeks. Twenty-one pregnancies were selectively terminated; nine spontaneous abortions followed the procedure and one fetal loss after 28 weeks was recorded; 153 pregnancies are in progress and 169 delivered fetuses are alive and well. Transabdominal biopsy is a feasible and effective technique for CVS.  相似文献   
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