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J. R. AKEROYD F.L.S. S. M. WALTERS F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1987,95(4):223-226
AKEROYD, J. R. & WALTERS, S. M. 1987. Flora Europaea: the background to the revision of Volume One. Flora Europaea, published 1964-80, is a synthetic catalogue of Europe's vascular plants. Its publication has provided a relatively stable taxonomic and nomenclatural framework for the study of the flora of the continent, and has stimulated much further research and publication. The revision of the first volume of Flora Europaea, at Reading University, has been necessary in order to accommodate new information, to satisfy the continued demand for a complete Flora of Europe, and to update the original text. The revision is being carried out in cooperation with other European and Mediterranean floristic projects. 相似文献
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C. J. WALTERS 《Austral ecology》1993,18(1):53-61
Abstract Dynamic numerical models and field experiments play important roles in impact assessment and management. Unfortunately, extreme and simplistic views have developed about whether and how to use these tools, so their complementary values to the manager are often not recognized. We often hear the outrageous claim (or hope) that numerical models can synthesize ‘all’ relevant information for predicting the impact of policy choice, hence making experimental experience unnecessary. From experimentalists, we hear the equally naive criticism that ecological systems are so complex that nothing is predictable without experimental experience. What we usually get from the proponents of these extremes are either models that are dangerously unreliable, or experiments that provide nice scientific answers to the wrong questions. Wise use of modelling begins with the following points: (i) explicit modelling is an excellent way to clarify policy concerns and identify processes that are most likely to be important in making predictions about policy effects; (ii) we can do a very good job of modelling some processes and relationships, particularly those having to do with basic spatial and temporal scales of impact as related to physical transport, chemical transformations, and life history characteristics of indicator populations (longevity, delays and response times due to age structured rates of reproduction and mortality); and (iii) there are some important dynamic processes, such as long-term accumulation of toxic materials in the environment, that unfold over such large space and time scales as to preclude direct experimental study (leaving only the issue of which models to use in making predictions, not whether to model - unless the processes are simply ignored). But points (i) and (ii) represent steps that a good experimentalist will take anyway: be clear about what practical results an experiment is intended to produce, and do not waste effort on experiments to measure things that can be predicted reliably from existing knowledge. The key to successful use of modelling and experimentation in management is in making good judgements about the interface between points (ii) and (iii); that is, in making good judgements about both what variables cannot be reliably predicted, and of these, which to treat experimentally and which to gamble on predicting from models. 相似文献
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Action of nitro- and halophenols upon oxygen consumption and phosphorylation by a cell-free particulate system from arbacia eggs 总被引:3,自引:0,他引:3
CLOWES GH KELTCH AK STRITTMATTER CF WALTERS CP 《The Journal of general physiology》1950,33(5):555-561
1. The ability of 4,6-dinitrocresol and eight other substituted phenols to stimulate oxygen uptake and inhibit phosphorylation by a cell-free particulate system from unfertilized Arbacia eggs has been determined. Five of those agents can produce both stimulation of oxygen consumption and inhibition of phosphorylation; one inhibits both oxygen consumption and phosphorylation; and two have no effect on either oxygen consumption or phosphorylation. In every case the effects of these substituted phenols upon the cell-free particulate systems parallel those upon oxygen consumption and cleavage in the intact fertilized Arbacia eggs. 2. The data suggest that energy for cleavage of the Arbacia egg is provided at least in part by oxidative phosphorylation and that substituted phenols may block cleavage by interfering with generation and transfer of high-energy phosphate groups. 相似文献
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Traumatic pancreatitis should be considered as a diagnostic possibility when trauma to the epigastrium is followed by phenomena suggestive of intra-abdominal injury. The presence or absence of hyperamylasemia should be established immediately. Even when traumatic pancreatitis is believed to exist, any suggestion of injury to other viscera should indicate laparotomy. Retroperitoneal rupture of the duodenum may simulate traumatic pancreatitis in all respects, including hyperamylasemia. X-ray studies may be of value in differentiation.Non-complicated traumatic pancreatitis is best treated conservatively. Gunshot and knife wounds of the pancreas should be drained. 相似文献
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