PubMed · 12433147
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Kellyn S Betts. 2002-11-01. First U.S. ecosystems analysis reveals data gaps.. https://doi.org/10.1021/es022451k
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BACKGROUND: The objective of this study was to assess the current level of intensity-modulated radiation therapy (IMRT) use in the United States. METHODS: Three-hundred thirty-three randomly selected radiation oncologists were sent a 13-question survey regarding IMRT use. IMRT users were asked about the number of patients and sites treated, their reasons for adopting IMRT, and future plans for its use. Physicians who did not use IMRT were asked about their reasons for not using IMRT; whether they intended to adopt it in the future; and, if so, their reasons. RESULTS: One-hundred sixty-eight responses (50.5%) were received. Fifty-four respondents (32.1%) stated that they currently used IMRT. Most IMRT users (79.6%) had adopted IMRT since 2000. Academic physicians were more likely to use IMRT (P = 0.003) compared with private practitioners. The percent of physicians using IMRT in practices comprised of 1 physician, 2-4 physicians, or > 4 physicians were 15.4%, 28.4%, and 44.2%, respectively (P = 0.02). The most common sites treated were head and neck malignancies and genitourinary tumors. Of the 114 IMRT nonusers, 96.5% planned to use IMRT in the future, with 91.8% planning to use IMRT within 3 years. Among IMRT nonusers, the most common reason cited for not using IMRT was lack of necessary equipment. The most common reasons for adopting IMRT (users) or wanting to adopt IMRT (nonusers) were to improve delivery of conventional doses and to escalate dose. CONCLUSIONS: Approximately one-third of radiation oncologists in the United States use IMRT. However, this number appears to be growing rapidly. Efforts to ensure the safe and appropriate application of this new technology are warranted.
Rivers integrate the impacts of change in atmospheric and terrestrial systems; they then deliver these to the coast. En route geomorphological processes create dynamic and diverse habitats, both in-stream and in riparian/floodplain ecotones. The dynamics of channel change conflict with human resource development, the outcome is that many river and riparian environments have been significantly modified, complicating the interpretation of change. Collection of geomorphological data on both form and process has to date been overwhelmingly an academic pursuit; standard measurement networks and long-term monitoring have, as a result been largely absent-as in the Environmental Change Network (ECN), despite the emerging requirements of legislation such as the EU Water Framework Directive. In this paper, we utilise a unique set of repeat channel surveys and long-term bed-load sediment yields to provide guidance on both definitions of change and those variables and survey techniques which might form the basis, in future, of improved national-scale monitoring. The Environment Agency's River Habitat Surveys suggest the basis for channel typologies that could structure a sampling framework and rationalise the variables to be monitored. We also point to the value of more detailed geomorphological procedures in use at the catchment/project scale-Catchment Baseline Surveys and Fluvial Audits-as a standardised basis for monitoring the detail of change in the fluvial sediment system. A perfect opportunity to lay foundations for such monitoring activity has been provided in England and Wales by the winter floods of 2000/2001.
Long-term intensive monitoring in Europe is presently proceeding in more than 800 plots, where a number of investigations are carried out according to allegedly standardized protocols. While the potential of the program cannot be denied, certain aspects that are binding for data analysis may be a source of problems for future evaluation of program results. Here it is argued that: (i) current biological response indicators adopted by the program will not permit air pollution effects to be distinguished from effects due to other stressors and/or natural variation; (ii) the sampling strategy adopted to select monitoring sites does not enable European scale estimates of the status of attributes of interest or their changes; and that (iii) the sampling tactic suggested at plot level is ambiguous and cannot provide representative, unbiased estimates at plot scale. This latter point implies consequences when plot-level data are used in models, correlative studies and/or to infer cause-effect relationships.