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1.
The outcome of the pregnancy following (a) a mid-trimester termination of pregnancy (TOP) for fetal neural tube defect (NTD) (77 women=group 1); (b) mid-trimester TOP for fetal Down's syndrome (13 women=group 2); (c) delivery of a baby with NTD (119 women=group 3) was studied. The prenatal fetal loss was relatively high in all groups. In group 1 it was similar to that found in other studies after first trimester TOP, in group 2 it was associated with advanced maternal age and the unexpected finding in group 3 was not attributable to advanced maternal age. It is suggested that a previous NTD per se might increase the risk of fetal loss in the next pregnancy. A previous mid-trimester TOP for NTD was not associated with an increase in premature labour, small for dates babies or congenital abnormality in the next pregnancy, but there was a slight increase in the number of babies weighing less than 2500 g.  相似文献   
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Environmental Science and Pollution Research - Trophic status in surface waters has been mostly monitored by measuring soluble reactive phosphorus (SRP) and total phosphorus (TP). Additional to...  相似文献   
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Northern Ontario’s Ring of Fire/Wawangajing controversy constitutes a complex site of debate about the risks and benefits of mining in an area of major ecological significance that is also the ancestral territory of nine First Nation communities. This paper investigates the rhetorical alignments and divergences in public calls by Matawa First Nations tribal council and the Ontario Wildlands League for stronger environmental assessment of mining projects than that favoured by the Canadian government. Tracing the terminologies each group uses to describe the affected region and its inhabitants in its activist rhetoric about EA offers insight into the contingent, shifting ways in which wilderness advocacy and Indigenous justice discourses may speak together yet distinctly within contemporary environmental-natural resource disputes.  相似文献   
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This case study of an NGO's response to a food crisis due to crop failure focuses on the extent of active community participation at each stage of the project. With the current debate on the relationship between relief and development, and in particular the focus on encouraging more active community participation in relief responses, this study has relevance both in the Ethiopian context and beyond.
In this example the participation process was greatly facilitated by the prior relationship between the international NGO and the communities, and also by the high level of staff input into the project. Where resources or conditions are less favourable, as might be the case in similar responses by local NGOs or government agencies, the paper suggests that the participatory approach can be adapted or partially implemented and still result in a more effective and locally relevant operation.  相似文献   
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Cultures of a chorion biopsy taken from a pregnancy at risk of Bloom's syndrome revealed the high sister chromatid exchange frequency diagnostic of this rare disorder. To obtain the result, cultures were grown under standard conditions, with the addition of 10μM 5′;-bromodeoxyuridine for the final 48 h of incubation. This result demonstrates the feasibility of early prenatal diagnosis of Bloom's syndrome.  相似文献   
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Drought is a complex and highly destructive natural phenomenon that affects portions of the United States almost every year, and severe water deficiencies can often become catastrophic for agricultural production. Evapotranspiration (ET) by crops is an important component in the agricultural water budget; thus, it is advantageous to include ET in agricultural drought monitoring. The main objectives of this study were to (1) conduct a literature review of drought indices with a focus to identify a simple but simultaneously adequate drought index for monitoring agricultural drought in a semiarid region and (2) using the identified drought index method, develop and evaluate time series of that drought index for the Texas High Plains. Based on the literature review, the Standardized Precipitation‐Evapotranspiration Index (SPEI) was found to satisfy identified constraints for assessing agricultural drought. However, the SPEI was revised by replacing reference ET with potential crop ET to better represent actual water demand. Data from the Texas High Plains Evapotranspiration network was used to calculate SPEIs for the major irrigated crops. Trends and magnitudes of crop‐specific, time‐series SPEIs followed crop water demand patterns for summer crops. Such an observation suggests that a modified SPEI is an appropriate index to monitor agricultural drought for summer crops, but it was found to not account for soil water stored during the summer fallow period for winter wheat.  相似文献   
8.
Data were retrieved from 25 ocean sunfish (Mola mola) that were tagged with pop-up satellite archival tags in the southern Gulf of Maine (n = 6), off Nantucket Island (n = 17), and off the coast of Georgia (n = 2) between September 2005 and March 2008. Tags remained attached from 7 to 242 days, with a mean attachment period of (X ± SD) 107.2 ± 80.6 days. Ocean sunfish tagged in the Gulf of Maine and southern New England left those areas in the late summer and early autumn and moved south along the continental shelf break. Fish traveled as far south as the Bahamas and the Gulf of Mexico. By moving south, sunfish experienced similar mean sea surface temperatures throughout the tagging period. The maximum straight-line distance traveled by a tagged Mola mola was 2,520 km in 130 days. Two tagged ocean sunfish entered the Gulf of Mexico, one in the December and one in July. Movements were associated with frontal features created by the Gulf Stream and fish moved farther offshore in 2007 when the Gulf Stream was deflected from the shelf break.  相似文献   
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Summary Adults of the predatory beetleRhizophagus grandis are strongly attracted to both adult and larval frass of its specific prey,Dendroctonus micans, in walking bioassays. Spruce bark and resin are relatively unattractive. Solvent extracts of larval frass that were attractive toR. grandis adults in a flight wind tunnel contained a mixture of monoterpenes of host plant origin. A synthetic mixture of these monoterpenes, (+)—-pinene, (–)—-pinene, -phellandrene,dl limonene and 3-carene, was responsible for 70–80% of the activity of the most attractive extract. We suggest that a blend of monoterpenes in frass acts as a kairomone forR. grandis but that attraction to monoterpenes is only the first of a sequence of behavioural responses that ensures successful host location and identification.  相似文献   
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