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631.
Darryl L. York John L. Cummings Richard M. Engeman Kate L. Wedemeyer 《International biodeterioration & biodegradation》2000,45(3-4)
Bird strikes to aircraft are a serious economic and safety problem in the United States, annually causing millions of dollars in damage to civilian and military aircraft and the occasional loss of human life. We observed movements of 1236 neckbanded lesser Canada geese (Branta canadensis parvipes) to determine efficacy of hazing as a means to reduce goose presence at Elmendorf Air Force Base (EAFB), Anchorage, Alaska from August to October 1997. Emphasis was on movements of geese onto EAFB with additional data collected at the other two major airports in the area, Anchorage International Airport (AIA) and Merrill Field Airport (MFA). Daily observations indicated the presence of 208 individual neckbanded geese on EAFB, and 20% returned more than once after being hazed from EAFB. We identified three staging areas, geese utilized prior to entering EAFB, and three post-hazing dispersal sites. Collared geese began moving onto EAFB 30–40 days post-molt with the largest proportions moving onto EAFB 70–90 days post-molt. We observed 75 neckbanded geese on AIA from seven molting sites, and 23% returned more than once after being hazed from AIA. We observed 141 neckbanded geese on MFA from 14 molting sites, and 21% returned more than once after being hazed from MFA. Our data indicated that as long as local goose populations increase, large numbers of Anchorage area geese are likely to enter one of the airports creating a variety of management problems. Hazed geese returning to airports multiple times present a special hazard to aircraft safety because they appear to have become habituated to non-lethal scare tactics. We recommend an integrated management approach to limit the Anchorage area goose population utilizing various control techniques which are acceptable to Anchorage residents while continuing the hazing program at area airports. 相似文献
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Peter L. Steponkus Darryl G. Stout Joe Wolfe Richard V. E. Lovelace 《The Journal of membrane biology》1985,85(3):191-198
Summary Evidence is presented to support the hypothesis that electrical potentials generated during the freezing of aqueous solutions (the Workman-Reynolds effect) may contribute to the destabilization of the plasma membrane and cryoinjury of isolated protoplasts. Specifically. (1) electric potential diffrences of sufficient magnitude to cause lysis of the plasma membrane occur during the rapid freezing of isolated protoplasts suspended in sorbitol: (2) survival of protoplasts is inversely correlated with the magnitude of the potential difference and (3) cold acclimation increases the stability of the plasma membrane to applied electric fields. A discussion is given of the different physical phenomena though to be involved in the Workman-Reynolds effect. The basis equations for these phenomena are outlined. 相似文献
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Given near unanimity in the environmental and industrial communities about the need for a new generation of environmental technology, the policy process unfortunately lags behind in moving toward this objective. This article examines causes and remedies for this gap in the context of American environmental policy. U.S. environmental laws continue to be pervaded by structural biases against new technology, and the complexity of their administration exacerbates the problem. Within the last few years, several important reform initiatives have arisen from inside the regulatory community; however, these can only go so far, given the current statutory framework Congress, too long quiescent, needs to become involved. A legislative reform package is proposed consisting of four main elements: a legislative mandate that makes promotion of technological innovation an explicit environmental objective; elimination of structural features in current law that impede innovation; creation of a new framework for standard-setting and enforcement that puts every firm on a trajectory toward environmental and technological improvement; and enlisting regulation as a "demand-pull" for environmentally superior technology. 相似文献