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Kumar S Bhattacharyya JK Vaidya AN Chakrabarti T Devotta S Akolkar AB 《Waste management (New York, N.Y.)》2009,29(2):883-895
Solid waste management is one of the most challenging issues in urban cities, which are facing a serious pollution problem due to the generation of huge quantities of solid waste. This paper presents an assessment of the existing situation of municipal solid waste management (MSWM) in major cities in India. The quantity and composition of MSW vary from place to place, and bear a rather consistent correlation with the average standard of living. Extensive field investigations were carried out for quantification, analysis of physical composition, and characterization of MSW in each of the identified cities. The MSW management status (per the MSW Rules, 2000) has also been assessed, and an action plan for better management has been formulated; both are presented in this paper. Studies carried out in 59 selected cities in India have revealed that there are many shortcomings in the existing practices used in managing the MSW. These shortcomings pertain mainly to inadequate manpower, financial resources, implements, and machinery required for effectively carrying out various activities for MSWM. To overcome the deficiencies in the existing MSWM systems, an indicative action plan has been presented incorporating strategies and guidelines. Based on this plan, municipal agencies can prepare specific action plans for their respective cities. 相似文献
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Intrauterine fetal growth restriction (IUGR) is an important pregnancy complication associated with significant adverse clinical outcome, stillbirth, perinatal morbidity and cerebral palsy. To date, no uniformly accepted management protocol of Doppler surveillance that reduces mortality and cognitive morbidity has emerged. Aortic isthmus (AoI) evaluation has been proposed as a potential monitoring tool for IUGR fetuses. In this review, the current knowledge of the relationship between AoI Doppler velocimetry and preterm fetal growth restriction is reviewed. Relevant technical aspects and reproducibility data are reviewed as we discuss AoI Doppler and its place within the existing repertoire of Doppler assessments in placental insufficiency. The AoI is a link between the right and left ventricles which perfuse the lower and upper body, respectively. The clinical use of AoI waveforms for monitoring fetal deterioration in IUGR has been limited, but preliminary work suggests that abnormal AoI impedance indices are an intermediate step between placental insufficiency-hypoxemia and cardiac decompensation. Further prospective studies correlating AoI indices with arterial and venous Doppler indices and perinatal outcome are required before encorporating this index into clinical practice. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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We examined the temporal variation of lysosomal enzyme activities and lysosomal membrane stability in two stocks of blue
mussels (Mytilus edulis L., 1758) from the Magdalen Islands which differ in their susceptibility to summer mass-mortality. The activity of lysosomal
enzymes reflects the autolytic capacity which could be used during the transfer of reserves between storage and reproductive
tissues or for mobilisation of reserves for energy requirements. The peak of lysosomal enzyme activities in mantle tissue
in June 1992 probably was related with autolysis of storage cells to support maturation of the developing gametes. A second
peak of lysosomal enzyme activity which occurred in mid- August of 1992 and 1993 may help to cover energetic requirements
of maintenance metabolism during this period of high temperatures and reduced food quality. Measures of the destabilization
of lysosomal membranes in the digestive gland confirmed that mussels showed a significant stress response in mid-August. Mussels
from the stock with a higher susceptibility to summer mortality underwent a longer period of stress and accumulated less glycogen
between spawning and the stressful period in mid-August than mussels from the more resistant stock. In conclusion, our field
observations demonstrate high activities of lysosomes not only in spawning periods but also during stressful periods of high
temperatures and reduced food quality.
Received: 23 September 1997 / Accepted: 11 June 1998 相似文献
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