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991.
992.
Jan Deprest Marie-Paule Emonds Jute Richter Philip DeKoninck Tim Van Mieghem Dominique Van Schoubroeck Roland Devlieger Luc De Catte Liesbeth Lewi 《黑龙江环境通报》2011,31(7):661-666
With the increased use of invasive fetal procedures, the number of women facing post-procedure membrane rupture is increasing. Here we review the use of platelets and fresh frozen plasma for sealing iatrogenic fetal membrane defects by describing the mechanisms of action of the amniopatch procedure as well as published experience. In cases of iatrogenic preterm pre-labour rupture of the membranes, amniopatch effectively seals the fetal membranes in over two-thirds of cases. There is a risk of 16% of in utero fetal death, which may occur at varying intervals from the procedure and often for unknown reasons. Amniopatch has also been used as a treatment of chorionic membrane separation. In summary, current experience suggests that in cases of early onset but persistent amniotic fluid leakage following an invasive fetal procedure, amniopatch is an option. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
993.
Epiphytic lichens as indicators for changes in air pollution and climate. Results of a comparative survey 1989/2007 in north-west Germany Background, aim, and scope Lichens growing on tree bark (epiphytic lichens) respond very sensitively to environmental effects such as chemical substances and air temperature. Therefore, they are used as biomonitors for atmospheric pollution in environmental assessments. Based on a survey of epiphytic lichens in 1989, a repetition was performed in an intensively-used agricultural area of north-west Germany in 2007. The objective of this study was to assess possible changes in air pollution and climate. Materials and methods The study is based on a comparative inventory of epiphytic lichens, growing on 335 trees at 45 monitoring sites. A simplified half quantitative survey technique of the first survey was used. Results Indeed, major changes to the epiphytic lichen flora were found. Overall, nearly all monitoring points showed an increase in the level of lichen species. A sharp decrease in acidophileous species and a sharp increase in basidophileous and nitrophileous species were detected. In addition, an increase in thermophileous species which are mainly inhabitants of southern European countries was observed, combined with decreases in boreo-montanic species. Discussion These trends correspond with supra-regional observations. They are primarily attributed to changes in air pollution involving a decrease in SO2 and an increase in NH3 concentrations. Clear effects from climate change are evident as well. Conclusions Changes to epiphytic lichens over a 18-year period could be demonstrated using a relatively low-cost investigation. They are relevant for assessing the changing environmental situation, which is of great importance for other organism groups and ecosystems. Recommendations and perspectives Using standardized techniques epiphytic lichens are suitable bioindicators for obtaining different types of information about the air pollution in urban areas and in intensively-used agricultural regions. Furthermore they are obviously good indicators of temperature changes in their environment. More research is needed about the suitability of epiphytic lichens for a biomonitoring of climate changes. 相似文献
994.
The social environment of many species includes synchronous maturation of siblings in family groups, followed by limited dispersal
of adults from their natal site. Under these conditions, females may experience high encounter rates with same-age siblings
during mate searching, increasing their risk of inbreeding. If inbreeding depression occurs, mating with a sibling is often
considered maladaptive; however, in some contexts, the inclusive fitness benefits of inbreeding may outweigh the costs, favoring
females that tolerate some level of inbreeding depression. We evaluated mating patterns in the treehopper Umbonia crassicornis, a semelparous species in which females encounter same-age siblings during mate searching. A female U. crassicornis that mates with a brother suffers from inbreeding depression. We used a free-choice mating design that offered females simultaneous
mating opportunities with three groups of males: siblings, same-age nonsiblings, and older nonsiblings. These groups represent
the types of males typically encountered by females during mate searching. Our goal was to assess whether mating patterns
were influenced by inbreeding avoidance by evaluating two hypotheses: kin discrimination and age-based mating (older males
cannot be siblings in this species). There was no difference in the proportions of females mating with siblings vs nonsiblings,
suggesting an absence of kin discrimination. However, females mated with a greater proportion of older vs younger males. Given
that females do not avoid siblings as mates despite a cost to inbreeding, our results provide a possible example of inbreeding
tolerance. We also discuss some factors that may have contributed to the mating advantage of older males. 相似文献
995.
996.
Large-scale patterns of shell variation in Littorina striata, a planktonic developing periwinkle from Macaronesia (Mollusca: Prosobranchia) 总被引:2,自引:1,他引:1
Littorina striata King and Broderip, 1832 is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species displays
a high degree of shell variation involving size and sculpture (nodulose vs smooth shells). The present work provides a preliminary
account of some aspects of this shell variation on wave-exposed shores over the entire geographical range of the species.
Based on morphological patterns observed among other prosobranchs it was predicted that southern specimens of L. littorina should on the average be larger, heavier, more nodulose, and should show more shell repair marks, than northern specimens.
These expectations were confirmed for shell size and weight. In contrast, there was no consistent pattern in nodulosity between
archipelagos, even though there were differences at much smaller scales. Shell repair marks were more prevalent in northern
populations, but this trend was only due to a significant N–S difference among nodulose shells. This is surprising as nodulose
shells displayed significantly fewer shell repair marks than smooth shells. These observations were tentatively interpreted
as a function of presumed differential N–S patterns of wave action and ambient temperatures. In this context, wave action
in Macaronesia seems to increase in the south (contrary to what current theories predict). This atypical situation may confound
the interpretation of morphological patterns in L. striata so that firm conclusions cannot be drawn without further experimental work at different spatial scales. Nevertheless, it
seems that generalisations about macrogeographic shell morphology patterns, based on interspecific comparisons, are not directly
applicable to intraspecific patterns, and may strongly depend on local conditions which make adequate sampling and data treatment
very difficult.
Received: 10 September 1997 / Accepted: 15 January 1998 相似文献
997.
This paper focuses on the study of eleven environmental impact categories produced by several municipal solid waste management systems (scenarios) operating on a provincial scale in Southern Italy. In particular, the analysis takes into account 12 management scenarios with 16 management phases for each one. The only difference among ten of the scenarios (separated kerbside collection of all recyclables, glass excepted, composting of putrescibles, RDF pressed bales production and incineration, final landfilling) is the percentage of separated collection varying in the range of 35–80%, while the other two scenarios, for 80% of separate collection, consider different alternatives in the disposal of treatment residues (dry residue sorting and final landfilling or direct disposal in landfill). The potential impacts induced on the environmental components were analysed using the life cycle assessment (LCA) procedure called “WISARD” (Waste Integrated System Assessment for Recovery and Disposal). Paper recycling was the phase with the greatest influence on avoided impacts, while the collection logistics of dry residue was the phase with the greatest influence on produced impacts. For six impact categories (renewable and total energy use, water, suspended solids and oxydable matters index, eutrophication and hazardous waste production), for high percentages of separate collection a management system based on recovery and recycling but without incineration would be preferable. 相似文献
998.
999.
A. C. Engels L. Joyeux C. Brantner B. De Keersmaecker L. De Catte D. Baud J. Deprest T. Van Mieghem 《黑龙江环境通报》2016,36(3):266-273
The fetal central nervous system can already be examined in the first trimester of pregnancy. Acrania, alobar holoprosencephaly, cephaloceles, and spina bifida can confidently be diagnosed at that stage and should actively be looked for in every fetus undergoing first-trimester ultrasound. For some other conditions, such as vermian anomalies and agenesis of the corpus callosum, markers have been identified, but the diagnosis can only be confirmed in the second trimester of gestation. For these conditions, data on sensitivity and more importantly specificity and false positives are lacking, and one should therefore be aware not to falsely reassure or scare expecting parents based on first-trimester findings. This review summarizes the current knowledge of first-trimester neurosonography in the normal and abnormal fetus and gives an overview of which diseases can be diagnosed. © 2016 John Wiley & Sons, Ltd. 相似文献
1000.
Disaster Management in the Caribbean 总被引:1,自引:0,他引:1
Jean Luc Poncelet 《Disasters》1997,21(3):267-279
This paper identifies the main trends in approaches to disaster management in the Caribbean at both regional and national levels over the past 20 years. It highlights the main reasons why and how the region has moved from an ad hoc response to an organised approach. Finally, it suggests ways in which future regional and national disaster management could be improved. 相似文献