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201.
The livebirth prevalence of autosomal chromosomal anomalies is determined by several factors, including maternal age distribution and the impact of prenatal cytogenetic diagnosis (PCD). The impact of PCD varies between countries, as the indications and the uptake vary. In a previous study we described differences in Down syndrome prevalence and the proportion of older mothers. We have now made a survey of the official PCD policies in 25 regions in 13 European countries for the period 1989–1991. In two countries, termination of pregnancy was not available. In the other 11 countries, international agreement existed on five indications: advanced maternal age, a previous child with a chromosomal anomaly, parents who are carriers of a balanced translocation, mothers who are carriers of an X-linked disorder, and malformations at ultrasound. The exact limit for advanced maternal age varied from 35 to 38 years. There was a considerable variation for the indications advanced paternal age, amniocentesis for AFP or DNA, parental anxiety, a previous child with a congenital anomaly, abnormal maternal serum markers, and exposure to radiation/chemotherapy. The PCD uptake for mothers above the maternal age limit varied from 10 to 88 per cent. International harmonization of the indications for PCD is not considered feasible at present, because of the rapid changes in PCD policies even within countries. 相似文献
202.
Reclamation of processed oil shale disposal areas in the arid and semi-arid regions of Utah, Colorado and Wyoming faces several challenging problems. Shallow topsoil, harsh climate and limited water supply and low suitability of processed oil shale as a plant growth medium must be addressed if any reclamation plan is to be successful.A prototype reclamation plan that addressed the harsh environmental conditions was proposed early in the development of oil shale in eastern Utah. Studies to validate the reclamation plan were initiated in 1978 on a simulated oil shale disposal area at Anvil Points, Colorado.Four native shrubs, one forb and a grass, were successfully established by planting container-grown transplants into a topsoil-filled V-shaped trench. Supplemental water was provided from an adjacent water harvesting slope. The roots of the transplanted species grew into the adjacent shale from the soil trench, thus indicating their adaptability to the adverse oil shale conditions.Support for this research was provided by the White River Shale Corporation, Salt Lake City, Utah. 相似文献
203.
Efficacy of insurance for organisational disaster recovery: case study of the 2010 and 2011 Canterbury earthquakes 下载免费PDF全文
Insurance is widely acknowledged to be an important component of an organisation's disaster preparedness and resilience. Yet, little analysis exists of how well current commercial insurance policies and practices support organisational recovery in the wake of a major disaster. This exploratory qualitative research, supported by some quantitative survey data, evaluated the efficacy of commercial insurance following the sequence of earthquakes in Canterbury, New Zealand, in 2010 and 2011. The study found that, generally, the commercial insurance sector performed adequately, given the complexity of the events. However, there are a number of ways in which insurers could improve their operations to increase the efficacy of commercial insurance cover and to assist organisational recovery following a disaster. The most notable of these are: (i) better wording of policies; (ii) the availability of sector‐specific policies; (iii) the enhancement of claims assessment systems; and (iv) risk‐based policy pricing to incentivise risk reduction measures. 相似文献
204.