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排序方式: 共有508条查询结果,搜索用时 31 毫秒
1.
Thomas S. Lowry John C. Bright Murray E. Close Christina A. Robb Paul A. White Stewart G. Cameron 《国际水资源开发杂志》2003,19(4):579-592
The primary objective of this project is to identify gaps, whether real or perceived, that hinder effective groundwater management in New Zealand. These gaps show as gaps in information, gaps in implementation, gaps in technological and management tools, and gaps in understanding of fundamental processes. The secondary objective is to propose a management strategy to close the identified gaps. Several methods are used to meet these objectives: surveys distributed to selected staff in each regional council; the review of various written reports; the analysis of land-use databases; and private consultation within each regional council. Results show that groundwater management in New Zealand is generally reactionary with the main gaps being in strategic planning and national guidelines. Most gaps appear to be predominantly information and implementation issues. In some cases there are gaps in the understanding of fundamental processes within an aquifer system, including the long-term effects of land-use on groundwater quality. An adaptive management approach is suggested as a means of closing these gaps. 相似文献
2.
Pax genes are expressed in specific patterns in the nervous system during development and in the adult. Recent findings suggest a link between the expression of Pax-2 and axonal guidance. Mice with a targeted deletion of Pax-2 are an excellent tool for studying axonal pathfinding at the molecular level, especially with respect to the optic chiasm. The date reviewed here suggest that Pax-2 regulates the expression of surface molecules involved in contact attraction and that the mutual regulation of the expression of Pax-2 and the Sonic hedgehog gene is of importance in the formation of the chiasm region. 相似文献
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Levin Harvey S.; Mendelsohn Dianne; Lilly Matthew A.; Fletcher Jack M.; Culhane Kathleen A.; Chapman Sandra B.; Harward Harriet; Kusnerik Lori; Bruce Derek; Eisenberg Howard M. 《Canadian Metallurgical Quarterly》1994,8(2):171
To investigate the relationship of severity of pediatric closed head injury (CHI), the contribution of frontal lobe lesions, and age at testing (6–10 yr olds vs 11–15 yr olds) to cognitive deficit, 134 head-injured patients were given the Tower of London (TOL) task and underwent magnetic resonance imaging. 89 normal controls were given the TOL for comparison. Severity of CHI and age at testing were strongly related to cognitive performance on the TOL, including the frequency of breaking the rules. Volume of frontal lobe lesion (but not extrafrontal lesion) contributed to the prediction of perfomance on the TOL even after severity of injury was taken into account. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Describes 2 independent reports, recently completed by the American Psychological Association (APA) and the US Congress Office of Technology Assessment, that examined many scientific and measurement issues concerning integrity testing (e.g., validity, criterion relevance). Background data are offered on a variety of tests collected by a survey of test publishers, providing a view of the industry's scope (e.g., test audience, user screening, score reporting) not available elsewhere. In the light of APA's Ethical Principles for Psychologists and Code of Conduct (APA, 1992), unresolved concerns are addressed that have a wide range of implications for the profession of psychology, the testing industry, and public policy (e.g., cutting scores, user screening and training, and test marketing practices). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Ed Lowry 《Computer Standards & Interfaces》1991,13(1-3):105-108
Maximizing the satisfaction of a value in an engineering design is usually limited by tradeoffs in which other values become unacceptably sacrificed. In a few cases, however, the maximization is limited by a boundary between what is mathematically possible and what is not. Round wheels, vertical pillars, and binary memory elements are examples of optimum engineering structures which result from such mathematical limits. It is proposed that optimum characteristics of a language data model result similarly by minimizing the variety of primitive data objects, the complexity of those objects, and the number of objects needed to represent data states. Reducing these measures is needed to combine both rich data structure and powerful operations in one language. The minimizations lead to a narrow range of designs for language semantics in which the potential advantages of specialization is small compared with the advantages of commonality. Universal language for support of technical literacy appears to be an appropriate scope of generality in language design. 相似文献
7.
Dianne Mulcahy 《Pedagogy, Culture & Society》2006,14(1):55-69
Recently, issues of space and spatiality have been taken up in education, though less so in teacher education. This article examines the significance of space for pedagogy and identity in teacher education. Drawing on topological approaches to the study of pedagogy, it explores the potential of a problem-based approach to teacher education to link the professional knowledge produced through teacher education programmes in the academy to professional practice in schools. It promotes a theoretical and empirical imperative to look keenly to the pedagogic spaces created by students (here, student teachers) to challenge established hierarchies of theory and practice. Essentially interrogatory, these spaces open up the possibility of the negotiation of professional identity across differences of school and academy. Overall, the argument concerns the co-constitutive character of pedagogy, spatiality and identity. Pedagogy emerges as a threshold practice that involves a constant weaving to and fro between spaces and selves. 相似文献
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Docosahexaenoic acid (22∶6n−3) can be synthesized in the liver and/or brain from α-linolenic acid (18∶3n−3) and is required
in large amounts in structural membranes of developing brain and retina. The adequacy and efficacy of formulas containing
18∶3n−3 and/or fish oil in providing 22∶6n−3 for deposition was investigated in piglets fed formula from birth to 15 days.
The test formulas contained high (HL) or low (LL) 18∶3n−3 (3.9 or 0.7% of the total formula fatty acids, respectively), or
low 18∶3n−3 plus fish oil (LL+FO) to provide C20 and C22 n−3 polyunsaturated fatty acids (0.8% of total fatty acids). Fatty acid analyses of synaptic plasma membrane and retina ethanolamine
phospholipids (EPL), which are especially enriched in 22∶6n−3, were compared to those of 15-day-old piglets fed sow milk (SM).
Feeding LL resulted in lower 22∶6n−3 in synaptic plasma membrane. Fatty acid levels in HL and LL+FO piglets were equivalent
to SM, with the exception of lower 22∶5n−3 in the synaptic plasma membrane of LL+FO and in the retina of HL and LL+FO-fed
piglets. Levels of 22∶4n−6 were also lower in the retina of the LL+FO group. The results suggest formula 18∶3n−3 is at least
24% as effective as C20 and C22 n−3 fatty acids as a source of membrane 22∶6n−3. This study shows dietary 18∶3n−3, as the only n−3 fatty acid, can support
deposition of comparable percentage of 22∶6n−3 to natural milk. Fish oil also supported tissue levels of 22∶6n−3 similar to
natural milk; however, lower 22∶4n−6 may indicate possible inhibitory effects on n−6 metabolism.
Recipient of the 1967 Science and Engineering Scholarship, Natural Sciences & Engineering Research Council of Canada. 相似文献
10.
Information Systems Frontiers - What is happening in hacker’s minds when they are committing criminal activities? How black hat hackers manage nerves, which is about managing fear and... 相似文献