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Mary C. Phelan R. Curtis Rogers Ron C. Michaelis C. Lynn Moore Will Blackburn 《黑龙江环境通报》2001,21(6):457-460
Mosaicism for trisomy 13 and triploidy was detected by amniocentesis performed at 18 weeks' gestation because of fetal anomalies. Pregnancy continued and a live-born male was delivered vaginally at 37 weeks. The infant had features common to both trisomy 13 and triploidy: intrauterine growth retardation (IUGR), small abnormal ears, cleft palate, and a small jaw. In addition, he had complete cutaneous syndactyly of fingers 3 and 4 and partial syndactyly of the toes, as seen in triploidy. Mixoploidy for trisomy 13 and triploidy was confirmed postnatally in blood, skin, and placenta. Examination of chromosome heteromorphisms and DNA markers suggested the presence of two maternal contributions in the triploid cell line. In addition, the extra chromosome 13 in the trisomic cell line was derived from the mother. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
3.
The usability of high-resolution satellite imagery for estimating spatial water quality patterns in urban water bodies is evaluated using turbidity in the lower Charles River, Boston as a case study. Water turbidity was surveyed using a boat-mounted optical sensor (YSI) at 5 m spatial resolution, resulting in about 4,000 data points. The ground data were collected coincidently with a satellite imagery acquisition (IKONOS), which consists of multispectral (R, G, B) reflectance at 1 m resolution. The original correlation between the raw ground and satellite data was poor (R2 = 0.05). Ground data were processed by removing points affected by contamination (e.g., sensor encounters a particle floc), which were identified visually. Also, the ground data were corrected for the memory effect introduced by the sensor's protective casing using an analytical model. Satellite data were processed to remove pixels affected by permanent non-water features (e.g., shoreline). In addition, water pixels within a certain buffer distance from permanent non-water features were removed due to contamination by the adjacency effect. To determine the appropriate buffer distance, a procedure that explicitly considers the distance of pixels to the permanent non-water features was applied. Two automatic methods for removing the effect of temporary non-water features (e.g., boats) were investigated, including (1) creating a water-only mask based on an unsupervised classification and (2) removing (filling) all local maxima in reflectance. After the various processing steps, the correlation between the ground and satellite data was significantly better (R2 = 0.70). The correlation was applied to the satellite image to develop a map of turbidity in the lower Charles River, which reveals large-scale patterns in water clarity. However, the adjacency effect prevented the application of this method to near-shore areas, where high-resolution patterns were expected (e.g., outfall plumes). 相似文献
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Arachnoid cysts are an uncommon central nervous system malformation, representing only 1 per cent of all intracranial masses. We report the second-trimester prenatal diagnosis of a posterior fossa arachnoid cyst, associated with an unbalanced X;9 translocation. 相似文献
6.
Marcy C. Speer Margaret A. Pericak-Vance Larry H. Yamaoka James Koh Wu-Yen Hung Peter C. Gaskell Jr. Jeffery M. Vance Richard J. Bartlett Allen D. Roses 《黑龙江环境通报》1988,8(6):427-437
Accurate carrier testing and prenatal diagnosis in Duchenne muscular dystrophy (DMD) families is facilitated when an Xp21 deletion is found to be segregating within a family. We discuss the results of the DNA testing in two families, one in which DNA from affected males was available for study and the other in which no DNA from an affected male was available. Factors complicating the counselling of DMD deletion families are outlined. 相似文献
7.
Wetland loss and substitution by the Section 404 permit program in southern California,USA 总被引:1,自引:0,他引:1
To test the effectiveness of the 404 permit program in preventing a net loss of wetland resources, 75 Section 404 projects permitted in the years 1987–1989 and located in a portion of southern California were evaluated. From this group of projects, 80.47 ha of wetlands were affected by Section 404 permits and the Army Corps of Engineers required 111.62 ha of wetland mitigation. To verify the successful completion of each mitigation project, all 75 project sites were visited and evaluated based on the amount of dead vegetation, growth and coverage, and the number of invasive species. Based on the field verification results, the actual amount of completed mitigation area was 77.33 ha, resulting in a net loss of 3.14 ha of wetland resources in the years 1987–1989. By comparing the types of wetlands lost to the types of wetlands mitigated, it is apparent that, in particular, freshwater wetlands are experiencing a disproportionately greater loss of area and that riparian woodland wetlands are most often used in mitigation efforts. The net result of these accumulated actions is an overall substitution of wetland types throughout the region. Results also indicate that, typically, large-scale mitigation projects are more successful compared to smaller projects and that successful compliance efforts are not evenly distributed throughout the region. We recommend that better monitoring, mitigation in-kind, mitigation banking, and planning on a regional or watershed scale could greatly improve the effectiveness of the Section 404 permitting program. 相似文献
8.
Results from a survey of power utility biologists indicate that terrestrial biodiversity is considered a major issue by only a few utilities; however, a majority believe it may be a future issue. Over half of the respondents indicated that their company is involved in some management for biodiversity, and nearly all feel that it should be a goal for resource management. Only a few utilities are funding biodiversity research, but a majority felt more research was needed. Generally, larger utilities with extensive land holdings had greater opportunities and resources for biodiversity management. Biodiversity will most likely be a concern with transmission rights-of-way construction and maintenance, endangered species issues and general land resource management, including mining reclamation and hydro relicensing commitments. Over half of the companies surveyed have established voluntary partnerships with management groups, and biodiversity is a goal in nearly all the joint projects. Endangered species management and protection, prevention of forest fragmentation, wetland protection, and habitat creation and protection are the most common partnerships involving utility companies. Common management practices and unique approaches are presented, along with details of the survey. 相似文献
9.
Science in the public process of ecosystem management: lessons from Hawaii, Southeast Asia, Africa and the US Mainland 总被引:1,自引:0,他引:1
Gutrich J Donovan D Finucane M Focht W Hitzhusen F Manopimoke S McCauley D Norton B Sabatier P Salzman J Sasmitawidjaja V 《Journal of environmental management》2005,76(3):197-209
Partnerships and co-operative environmental management are increasing worldwide as is the call for scientific input in the public process of ecosystem management. In Hawaii, private landowners, non-governmental organizations, and state and federal agencies have formed watershed partnerships to conserve and better manage upland forested watersheds. In this paper, findings of an international workshop convened in Hawaii to explore the strengths of approaches used to assess stakeholder values of environmental resources and foster consensus in the public process of ecosystem management are presented. Authors draw upon field experience in projects throughout Hawaii, Southeast Asia, Africa and the US mainland to derive a set of lessons learned that can be applied to Hawaiian and other watershed partnerships in an effort to promote consensus and sustainable ecosystem management. Interdisciplinary science-based models can serve as effective tools to identify areas of potential consensus in the process of ecosystem management. Effective integration of scientific input in co-operative ecosystem management depends on the role of science, the stakeholders and decision-makers involved, and the common language utilized to compare tradeoffs. Trust is essential to consensus building and the integration of scientific input must be transparent and inclusive of public feedback. Consideration of all relevant stakeholders and the actual benefits and costs of management activities to each stakeholder is essential. Perceptions and intuitive responses of people can be as influential as analytical processes in decision-making and must be addressed. Deliberative, dynamic and iterative decision-making processes all influence the level of stakeholder achievement of consensus. In Hawaii, application of lessons learned can promote more informed and democratic decision processes, quality scientific analysis that is relevant, and legitimacy and public acceptance of ecosystem management. 相似文献
10.
David G. Angeler Craig R. Allen Hannah E. Birgé Stina Drakare Brendan G. McKie Richard K. Johnson 《Ambio》2014,43(1):113-125
Freshwater ecosystems are important for global biodiversity and provide essential ecosystem services. There is consensus in the scientific literature that freshwater ecosystems are vulnerable to the impacts of environmental change, which may trigger irreversible regime shifts upon which biodiversity and ecosystem services may be lost. There are profound uncertainties regarding the management and assessment of the vulnerability of freshwater ecosystems to environmental change. Quantitative approaches are needed to reduce this uncertainty. We describe available statistical and modeling approaches along with case studies that demonstrate how resilience theory can be applied to aid decision-making in natural resources management. We highlight especially how long-term monitoring efforts combined with ecological theory can provide a novel nexus between ecological impact assessment and management, and the quantification of systemic vulnerability and thus the resilience of ecosystems to environmental change. 相似文献