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121.
We describe successful prenatal diagnosis in four pregnancies at risk for non-ketotic hyperglycinemia, two affected and two unaffected, using the glycine level and the glycine/ serine ratio in amniotic fluid obtained at 16 weeks gestational age. Although this method of prenatal diagnosis for non-ketotic hyperglycinemia has been effective in our hands the narrow differences between affected and unaffected pregnancies indicate the need for caution concerning its reliability.  相似文献   
122.
Abstract: Flood management problems are inherently complex, time‐bound and multi‐faceted, involving many decision makers (with conflicting priorities and dynamic preferences), high decision stakes, limited technical information (both in terms of quality and quantity), and difficult tradeoffs. Multi‐Criteria Decision Support Systems (MCDSS) can help to manage this complexity and decision load by combining value judgments and technical information in a structured decision framework. A brief overview of MCDSS is presented, an original MCDSS architecture is put forth, and future research directions are discussed, including extensions to Multi‐Criteria Spatial Decision Support Systems and group MCDSS (as flood management involves shared resources and broad constituencies). With application to the September 11‐12, 2000 Tokai floods in Japan, the proposed multi‐criteria decision support instruments enhance communication among stakeholders and improve emergency management resource allocation. In summary, by making the links among flood knowledge, assumptions and choices more explicit, MCDSS increases stakeholder satisfaction, saves lives, and reduces flood management costs, thereby increasing decision‐making effectiveness, efficiency and transparency.  相似文献   
123.
Twenty-two cases of cystic hygromas were diagnosed prenatally at Eastern Virginia Medical School and followed through the neonatal period. Our series was combined with 131 cases which have been described in the literature. Karyotypes were obtained in 110 fetuses and 80 (72·7 per cent) were abnormal. Fifty-one were not terminated: 30 with abnormal and 21 with normal karyotypes. There were no neonatal survivors in the group with abnormal karyotypes. There were five survivors in the 21 with normal karyotypes but only 2/21 without severe medical complications. Combining our series with those previously reported in the literature would suggest only a 2–3 per cent rate of intact survivors when fetal cystic hygromas are diagnosed in utero. This information should be helpful when counselling patients whose pregnancies carry this diagnosis.  相似文献   
124.
In the Mid-Atlantic Bight, conger eels (Conger oceanicus) occur from the coastal portions of estuaries to the edge of the continental shelf. In deeper waters they occupy burrows of the tilefish (Lopholatilus chamaeleonticeps). Between 1972 and 1974 we examined the stomachs and intestines of conger eels from inshore New Jersey (USA) waters (n=35, with a total length: TL of 21 to 49 cm) and between 1980 and 1983 offshore (n=295, 50 to 125 cm TL)_collections. Eels from both areas fed primarily on decapod crustaceans and fish. The specific identity of prey items within these groups generally differed from inshore to offshore areas, probably reflecting the differences in prey availability. Foods of specimens collected offshore varied with size: smaller eels (<80 cm TL) fed most heavily on decapod crustaceans, whereas larger eels (>80 cm) consumed more fishes. The presence of some nocturnally active prey items in the gut, primarily the eel Lepophidium cervinum, suggests that conger eels are nocturnal feeders. This is supported by in situ observations that conger eels are present in some tilefish burrows during the day and are presumably out of burrows and foraging at night.  相似文献   
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126.
The paper presents an evaluation of post-project impacts of the Barekese Dam on three riparian communities downstream about 30 years after its construction. A network diagram, which incorporated a mathematical model, was used for impact identification and analysis. The expected environmental impacts, expressed as quantitative weighted impact scores, showed that the dam appeared to have exerted adverse impacts on the environmental quality of the communities. The impacts in the communities, however, increased with relative distances away from the dam and the river suggestive of cumulative impacts transmitted downstream. Strategic measures for improving environmental quality of the communities have been given.  相似文献   
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128.
Cesium-137, radium-226 and lead-210 profiles of a 25 cm sediment core give an indication of recent changes in land-ocean interactions at a polar coastal environment (Admiralty Bay, King George Island, Antarctica). The linear sedimentation accumulation rate at the study site calculated from the unsupported 210Pb profile was 6.7 mm/year from 1965 to 2005. A 3.5-fold increase in 137Cs concentrations was observed in the top layer of this sediment core. This sharp increase seems to indicate a recent redistribution of fallout radionuclides previously deposited on soil, vegetation and snow. These results imply enhanced land-ocean interactions at this site likely as a result of climate change. Because our results are based on a single core, additional investigations are needed to confirm our observations.  相似文献   
129.
ABSTRACT

Measurements of hydrocarbon (HC) emissions generated by the use of liquefied petroleum gas (LPG) in the metropolitan area of Guadalajara City (MAG) are presented in this work. Based on measurements in the course of distribution, handling, and consumption, an estimated 4407 tons/yr are released into the atmosphere. The three most important contributors to LPG emissions were refilling of LPG-fueled vehicles and commercial and domestic consumption. The MAG shows a different contribution pattern of LPG emission sources compared with that of the metropolitan area of Mexico City (MAMC). These results show that each megacity has different sources of emissions, which provides more accurate strategies in the handling procedures for LPG to decrease the impact in O3 levels. This work represents the first evaluation performed in Guadalajara City, based on current measurements, of the LPG contribution to polluting emissions.  相似文献   
130.
Identification of hot spots for urban fine particulate matter (PM(2.5)) concentrations is complicated by the significant contributions from regional atmospheric transport and the dependence of spatial and temporal variability on averaging time. We focus on PM(2.5) patterns in New York City, which includes significant local sources, street canyons, and upwind contributions to concentrations. A literature synthesis demonstrates that long-term (e.g., one-year) average PM(2.5) concentrations at a small number of widely-distributed monitoring sites would not show substantial variability, whereas short-term (e.g., 1-h) average measurements with high spatial density would show significant variability. Statistical analyses of ambient monitoring data as a function of wind speed and direction reinforce the significance of regional transport but show evidence of local contributions. We conclude that current monitor siting may not adequately capture PM(2.5) variability in an urban area, especially in a mega-city, reinforcing the necessity of dispersion modeling and methods for analyzing high-resolution monitoring observations.  相似文献   
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