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511.
We describe two cases of sonographic abnormalities associated with unusual chromosomal aberrations. Case 1 presented with a cystic hygroma at 12 weeks' gestation. Cytogenetic analysis revealed an unbalanced complex chromosome rearrangement implicating chromosomes 6, 13 and 21 (karyotype: 47,XX,t(6;21;14)(q14;q21;q21)mat,+21) and corresponding to a complete trisomy 21. This anomaly resulted from malsegregation of a maternal balanced three-way translocation. For case 2, an alobar holoprosencephaly was identified by ultrasonography at 23 weeks' gestation. Chromosomal analysis showed a recombinant rec (13), dup q chromosome, secondary to unequal crossing-over of a paternal pericentric inversion of chromosome 13, giving rise to partial trisomy 13q (karyotype: 46,XX,rec(13)dup(13q)inv(13)(p11q21)pat). These two cases illustrate the role of ultrasound in leading to detection not only of foetal chromosomal aberrations but also of rare balanced chromosomal rearrangements presented by one of the two parents. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
512.
Susan Maxman Architects was selected to design a new facility for the Women's Humane Society. The project, located on a disturbed site in Bensalem, Pennsylvania, presented an environmental challenge as a large part of the site is wetlands and the site is home to a large PECO power line. This case study describes the process of designing a facility that incorporates the concerns of environmental responsibility. It will show how the decisions in the design of the built environment can very much influence the well-being of the natural environment. It describes the ways in which the client was convinced that it was of great benefit to create a facility that was energy-efficient and environmentally sensitive. The article also explores the successes and failures of this process. It discusses barriers that exist in comprehensively incorporating sustainable design principles in these facilities and shows how it is applicable for the development of other facilities.  相似文献   
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The problem of managing scientific information for widespread availability and use can be overwhelming. At Oregon State University, the Quantitative Sciences Group has found a workable solution. The group has developed a Forest Science Data Bank (FSDB) to house data generated by scientists and collaborating researchers in the Andrews Long-Term Ecological Research program. Today the FSDB houses some 2400 data sets from over 350 existing ecological studies and adds about 20 new studies yearly. This paper describes what we have learned in setting up the FSDB as a facility that can be used by researchers who both deposit information in and retrieve information from the FSDB.  相似文献   
514.
The purpose of the present study was to examine how the mix of ability, experience, and personality impacts three types of team performance: technical‐administrative task performance, leadership task performance, and contextual performance. Relationships were tested using data collected from student management teams, who were required to plan and supervise the preparation and service of meals in a cafeteria‐style dining room patronized by university students, staff, and faculty. Results revealed that both team‐ and task‐related composition variables predicted leadership and contextual performance. Specifically, grade point average was significantly related to technical‐administrative task performance, and extraversion, neuroticism, and grade point average were related to leadership task performance. Agreeableness and restaurant experience predicted contextual performance. Surprisingly, conscientiousness did not account for significant variance in any of the three types of performance measured. The implications of these findings for the study of team performance in organizations are discussed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
515.
Using a case study approach, this article examines how the gender aspects of policy are implemented. It presents examples of gender policy implemented by different types of organizations, with particular emphasis on the water and sanitation sector. Implementing agencies include a UN agency, developing country governments, bilateral donors, and local and international NGOs. Observations from project implementation in the water and sanitation sector reveal the degree of effectiveness of the gender policies applied. Cases were chosen to provide interesting examples, rather than illustrate lessons that can be generalized. Much more research is needed before that can be done. The article also addresses project implementation strategy considerations, including how policies and implementation address women's needs, whether gender issues are treated separately or mainstreamed, and what factors are linked to successful implementation. Problems of coordination between different project implementation aspects/agents are endemic in the water and sanitation sector. Thus physical installation work is typically completed by engineers, while NGOs mostly deal with social aspects of projects, and the two groups often do not communicate effectively.  相似文献   
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Under current climate change scenarios, temperatures in Siberia are expected to increase, and consequently, fire is also expected to increase. Potential climate-induced change is difficult to assess in Siberia because ground-based fire data are not complete. This investigation introduces a method by which potential climate-induced change can be remotely evaluated. Mean fire return intervals are established for 58 ecosystems across Siberia using eight years of satellite-based area burned data (1995 to 2002). Mean fire return intervals should decrease under current climate change scenarios, however the results do not currently demonstrate consistent evidence of fire-induced change. The overall boreal forest mean fire return interval is lower than the published mean, inferring increased fire. Most notably, using satellite data to calculate mean fire return intervals in individual ecosystems for the entire population of fire is shown to be a viable method by which potential climate-induced land cover change can be evaluated.  相似文献   
519.
人口迁徙、汇款、生活轨迹及社会应变能力   总被引:7,自引:0,他引:7  
我们认为,人口变化的方方面面,包括迁徙,都影响个人和团体的社会应变能力以及基本资源基础的可持续性.社会应变能力是应对和适应通过适当的制度调节的环境和社会变化的能力.我们调查了当今越南沿海地区人口变化、社会应变能力以及可持续发展之间关系的一个侧面:迁徙和汇款对依赖于资源的人口源区居民群的影响.利用有关生活来源的纵向运动数据,我们发现移民出境和汇款对一个逐渐形成的社会和政治范围内的应变能力有抵消作用.移民出境是与不可持续的沿海养殖业的发展同时并存的,而不是起推动作用.日益增加的经济不平等削弱了社会应变能力.同时,多种经营和收入水平的不断提高有助于应变能力的增强.  相似文献   
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