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31.
Ultrasonographic features of a fetus at 18 weeks of gestation suggesting a body stalk anomaly are presented. These included a large abdominal anterior wall defect in apparent continuity with the placenta, severe kyphoscoliosis of the lower spine, the absence of one kidney, and a very short umbilical cord with only one umbilical artery. The amniotic fluid was reduced and the fetus was almost immobile at short-interval ultrasound examinations. The pregnancy was terminated and autopsy of the fetus showed abnormalities compatible with maldevelopment of both cephalic and caudal embryonic folds.  相似文献   
32.
Nepal SK  Nepal SA 《Ambio》2004,33(6):334-340
This study summarizes findings of a visitor impact study conducted in the Sagarmatha (Mt. Everest) National Park, Nepal. The effect of visitor use, and the influence of environmental characteristics on trail conditions are investigated. Seven trails divided into 208 trail segments, and with a total length of 90 kilometers were included in the assessment. A four-class rating system has been used for the assessment of trail conditions. Arc/Info and Arc/View geographic information system (GIS) are used to analyze spatial patterns of impacts. The study indicates a strong correlation between visitor use and trail degradation. However, locational and environmental factors are equally important variables. The study concludes that more systematic, and experimental studies are needed that can make a clear distinction between human-induced trail damage and the effects of natural factors.  相似文献   
33.
India ranks as the sixth largest producer of iron ore in the world. The current practice of washing iron ore in India generates as high as 18 million tonnes of tailings per year. These tailings are stored in massive ponds and pose environmental hazards. Safe disposal or utilisation of these materials thus remains a challenging task for the iron ore industry in India. The present paper describes a new development in managing these tailings by converting them into value added products such as ceramic floor and wall tiles for building application. These tiles have high strength and hardness compared to conventional tiles and conform to most of the EN standards. Energy economy and lower production costs are some other benefits.  相似文献   
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Vegetation conditions, i.e., plant cover, species richness, and the presence of exotic species, are compared along a high-use trail (Berg Lake Trail--BLT) and a low use trail (Mt. Fitzwilliam Trail--FWT) in Canada's Mt. Robson Provincial Park. We established 71 paired quadrats (1 m x 1 m), and assessed the amount of vegetation cover and species richness by four main lifeforms, i.e., woody species, herbaceous species, ferns, and moss, lichen and fungi. The following hypotheses were tested: (1) differences exist between control and trailside quadrats in vegetation cover, species richness and floristic diversity, and (2) differences exist between the high and low-use trails in the above-mentioned three parameters. Results show that for the majority of variables the differences between the control and trailside quadrats are statistically not significant. Variables showing significant differences are relative vegetation cover (for BLT only), exposed soil (BLT and FWT), herbaceous cover (FWT), moss, lichen and fungi cover (BLT), overall species richness (BLT), and herbaceous species richness (BLT). Ruderal and exotic species are present but only on trailside quadrats of the high-use trail. Results indicate that the Park administration's strategy to disperse use in the Mt. Robson Provincial Park should be examined critically, and some guidelines for acceptability of changes should be developed.  相似文献   
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To develop more efficient chemical methods for the demineralization of organic pollutants from water bodies, which one was also mimic to the nature, a degradation of methylene blue by Fe( Ⅲ ) and H2O2 in the absence of light instead of Fe( Ⅱ ) and H2O2 was studied. Results showed that use of Fe ( Ⅲ ) is more promising than Fe( Ⅱ ). The present study reflects that Fenton reaction is more efficient, in the presence of a small amount of salicylic acid is added which is a one of the priority pollutant.  相似文献   
38.
Decentralized power generation, using locally available biofuels from non-edible oilseeds, is an option for rural electrification in many developing countries. However, due to prevailing high price of non-edible oilseeds, such as Jatropha curcas, the cost of electricity generation is very high. This paper provides detailed financial analysis of straight vegetable oil (SVO)-based decentralized power project and proposes an innovative model for enhancing their financial viability. While for implementing agency operational cost recovery is the key for viability, affordable tariff is crucial for end-users. The paper attempts to estimate minimum desired price of electricity from the stakeholders' (producer and users) perspective using data gathered from selected operational SVO-based power generation projects in India. Analysis carried out in this paper indicates that operating the decentralized power plant at higher capacity utilization factor, by introduction of productive load, and differentiated tariffs for commercial and domestic consumers may not alone be sufficient to achieve the financial viability. The paper proposes an innovative integrated model of using biogas, obtained from the by-product de-oiled cake of non-edible oilseeds, as a feedstock for power generation, instead of using the SVO in engines. This reduces the fuel cost of power generation, thereby helping to bring down the tariff within the paying capacity of rural consumers. The main produce, viz. extracted non-edible oil, which was otherwise used as fuel for generating power, can be sold in local market for earning revenue, thereby enhancing the project’s economic viability. This paper sets forth the proposed integrated model as a viable biofuel-based decentralized power project for sustainable rural development in areas with adequate availability of oilseeds.  相似文献   
39.
The plastic components from waste mobile phones were sorted and characterized using visual, spectroscopic and thermal methods. The sustainable strength of the recovered plastics was investigated by comparing their mechanical and thermal properties with commercially used reference materials. The results revealed that the recovered polymers have significant potential to be reused. However, some properties, such as impact strength and tensile modulus, are significantly low compared to virgin materials and need further improvement. The samples were also tested for brominated flame retardants (BFRs) using gas chromatography–mass spectrometry technique, and the results indicated the absence of BFR in recovered plastics; hence, these can be processed without any risk of BFR toxicity.  相似文献   
40.
Hydrochemistry of surface water (pH, specific conductance, total dissolved solids, sulfate, chloride, nitrate, bicarbonate, hardness, calcium, magnesium, sodium, potassium) in the Mahanadi river estuarine system, India was used to assess the quality of water for agricultural purposes. The samples were studied for 31 different stations during six different seasons in the years 2001-2003. Chemical data were used for mathematical calculations (SAR, Na%, RSC, potential salinity, permeability index, Kelly's index, magnesium hazard, osmotic pressure and salt index) for better understanding the suitability river water quality for agricultural purposes. The river water is free from nitrate-nitrogen hazard and has much less osmotic pressure and RSC values. Further there is no complete precipitation of calcium and magnesium in the study area. The results revealed that waters of some polluted stations like Sambalpur down (D/s of Sambalpur town) and Kathjodi (Cuttack) down (D/s of Cuttack town) are unsuitable up to some extent, where as it is quite unsuitable in case of estuarine samples during the pre-monsoon and post-monsoon seasons. The results were verified by USSL and Wilcox diagrams, which show all the fresh water zone samples (low-medium salinity with low sodium) of the study area are in the 'Excellent to good' category and are suitable to irrigate all soils for semi-tolerant and tolerant as well as sensitive crops.  相似文献   
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