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71.
The water salinity of the Euphrates River as it enters Iraq, expressed as total dissolved solids (TDS), has more than doubled
compared to that of 1973. Downstream of Al Hindia Barrage, south of Baghdad, the salinity has increased gradually over the
last 30 years. The annual average TDS at Al Nassiriah, in the lower reaches of the Euphrates, has increased from 1,080 ppm
in 1979 to more than 4,500 ppm in 2001. Water quality of the Euphrates within Iraq has deteriorated due to the decreased flow
that is entering Iraq, diverted flows to the river from Al Tharthar Lake, and irrigation-return flow. The decreased flow from
upstream sources was due to reservoir construction projects. Water from Al Tharthar Lake and from irrigation return flow is
being diverted to the Euphrates to compensate for the upstream deficit. An environmental flow rate of 178 m3/s (annual minimum flow, 5.6 bcm or about one-third of historic minimum flow) is proposed as the minimum discharge that must
be flowing into Iraq to preserve the environment of the Euphrates River in Iraq. A flow of twice this amount would allow more
reasonable downstream management with an input average salinity of 760 ppm. 相似文献
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Rapid advancement in fetal diagnostic imaging has increased our ability to diagnose a multitude of anomalies in the prenatal period. The purpose of this chapter is to review our current understanding of prenatally diagnosed intra-abdominal lesions, and describe the current guidelines for the postnatal management and subsequent outcome for these lesions. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
77.
Advanced paternal age (APA) is associated with infertility and other reproductive risks. Studies looking at APA and outcomes have used different paternal age cut-offs, which has complicated systematic evaluations of reproductive risk associated with paternal aging. This review of the literature suggests that the impact of paternal aging on adverse reproductive outcomes is small, but significant. Studies suggest the incidence of paternal age effect disorders attributed to de novo autosomal dominant mutations is less than 0.5%. Other risks associated with APA include infertility, miscarriage, birth defects, poor neurodevelopmental outcomes, and childhood cancer. Although the increasing prevalence of APA has mirrored the rise in maternal age, this topic has not received similar attention. In this review, we summarize the available literature on the reproductive risks associated with APA to provide a framework for comprehensive genetic counseling and evidence-based management of APA pregnancies. 相似文献
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This paper demonstrates that Bishop's formulation deviates in a fundamental way from our model and, in so doing, Bishop has assumed the problem away. Bishop utilizes a utility function that is too general to discriminate the time pattern of consumption from that of production. Hence, the intertemporal nature of the goods that we analyzed cannot be captured by Bishop's representation. Furthermore, we show that current benefit cost methods that discount the benefit stream of a public asset are Pareto intertemporally inefficient. 相似文献