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EDWARD B. ARNETT W. KENT BROWN WALLACE P. ERICKSON JENNY K. FIEDLER BRENDA L. HAMILTON TRAVIS H. HENRY AAFTAB JAIN GREGORY D. JOHNSON JESSICA KERNS ROLF R. KOFORD CHARLES P. NICHOLSON TIMOTHY J. O'CONNELL MARTIN D. PIORKOWSKI ROGER D. TANKERSLEY JR. 《The Journal of wildlife management》2008,72(1):61-78
Abstract Wind has become one of the fastest growing sources of renewable energy worldwide, but widespread and often extensive fatalities of bats have increased concern regarding the impacts of wind energy development on bats and other wildlife. We synthesized available information on patterns of bat fatalities from a review of 21 postconstruction fatality studies conducted at 19 facilities in 5 United States regions and one Canadian province. Dominance of migratory, foliage- and tree-roosting lasiurine species (e.g., hoary bat [Lasiurus cinereus]) killed by turbines was consistent among studies. Bat fatalities, although highly variable and periodic, consistently peaked in late summer and fall, coinciding with migration of lasiurines and other species. A notable exception was documented fatalities of pregnant female Brazilian freetailed bats (Tadarida brasiliensis) in May and June at a facility in Oklahoma, USA, and female silver-haired bats (Lasionycteris noctivagans) during spring in Tennessee, USA, and Alberta, Canada. Most studies reported that fatalities were distributed randomly across turbines at a site, although the highest number of fatalities was often found near the end of turbine strings. Two studies conducted simultaneously in the same region documented similar timing of fatalities between sites, which suggests broader patterns of collisions dictated by weather, prey abundance, or other factors. None of the studies found differences in bat fatalities between turbines equipped with lighting required by the Federal Aviation Administration and turbines that were unlit. All studies that addressed relationships between bat fatalities and weather patterns found that most bats were killed on nights with low wind speed (<6 m/sec) and that fatalities increased immediately before and after passage of storm fronts. Weather patterns may be predictors of bat activity and fatality; thus, mitigation efforts that focus on these high-risk periods could reduce bat fatality substantially. We caution that estimates of bat fatality are conditioned by length of study and search interval and that they are biased in relation to how searcher efficiency, scavenger removal, and habitat differences were or were not accounted for. Our review will assist managers, biologists, and decision-makers with understanding unifying and unique patterns of bat fatality, biases, and limitations of existing efforts, and it will aid in designing future research needed to develop mitigation strategies for minimizing or eliminating bat fatality at wind facilities. 相似文献
43.
RICHARD A. ERICKSON 《The Journal of wildlife management》2008,72(2):575-579
ABSTRACT Student Chapters of The Wildlife Society serve the parent organization as a source of new members while promoting professional development among aspiring wildlife biologists. However, little is known about the operation of the Student Chapters across North America. I conducted an online survey between March and May 2006 to learn about variation among chapters and to define successful chapters with a quantifiable, objective parameter (e.g., the active members or budgets). I sent chapter advisors and student officers the online survey via e-mail. Of 92 Student Chapters known to the parent Society in 2005, 66 active and one inactive chapters responded. Activities, sizes, and budgets varied greatly among chapters. Additionally, perceived values of membership by survey participants matched the parent Society's goals. No clear definition of a successful chapter (e.g., those with the most money or members) emerged, but chapters faced some evident problems including apathy from students and advisors as well as a lack of support from the parent Society. Based upon the survey, I recommend Student Chapters have strong projects and activities as well as consider collaborating with other professional organizations. I recommend the parent Society continue to expand student programs and incorporate students into the Society. 相似文献
44.
We present an updated account of breast cancer treatment and of progress toward “precision” cancer therapy; we focus on new developments in diagnostic molecular pathology and breast cancer that have emerged during the past 2 years. Increasing awareness of new prognostic and predictive methodologies, and introduction of next generation sequencing has increased understanding of both tumor biology and clinical behavior, which offers the possibility of more appropriate therapeutic choices. It remains unclear which of these testing methodologies provides the most informative and cost-effective actionable results for predictive and prognostic pathology. It is likely, however, that an integrated “step-wise” approach that uses the traditional clinical-pathologic paradigms coordinated with molecular characterization of breast tumor tissue, will offer the most comprehensive and cost-effective options for individualized, “precision” therapy for patients with breast cancer. 相似文献
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ERICKSON JO HENSLEY TJ FIELDS M LIBBY RL 《Journal of immunology (Baltimore, Md. : 1950)》1957,78(2):95-103
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AGITATION DURING INCUBATION REDUCES THE TIME REQUIRED FOR A LYSINE MICROBIOLOGICAL GROWTH ASSAY USING AN ESCHERICHIA COLI AUXOTROPHIC MUTANT 总被引:2,自引:0,他引:2
X. LI A.M. ERICKSON S.C. RICKE 《Journal of Rapid Methods and Automation in Microbiology》2000,8(2):83-94
Microbiological assays involving Escherichia coli lysine auxotrophs must be optimized to facilitate routine use. Our objectives in this study were to characterize growth of an auxotrophic E. coli lysine mutant (American Type Culture Collection strain #23812) and examine the effect of agitation on E. coli mutant growth. A defined minimal salts basal medium was used and supplemented with various lysine concentrations. The E. coli lysine auxotroph responded to increasing lysine concentration with increasing optical density. When maximum optical density (MOD) was determined for the auxotroph, a linear increase was obtained as lysine concentrations were increased (R2 ± 0.96) for both agitation and static cultures. Growth rates were not significantly (p > 0.05) affected by lysine concentrations, cultural conditions or their combined effect. However, growth with agitation significantly (p < 0.05) reduced the assay time by shortening the lag phase and causing stationary phase to occur earlier. The values of R2 (± 0.96) relatively remained constant over the range while the bacterial population were in the stationary phase. In conclusion, the lysine growth assay using the E. coli lysine auxotroph can be made more rapid by agitating the culture during incubation. 相似文献
48.
The influence of catchment land use on stream integrity across multiple spatial scales 总被引:37,自引:1,他引:37
1. Despite wide recognition of the need for catchment-scale management to ensure the integrity of river ecosystems, the science and policy basis for joint management of land and water remains poorly understood. An interdisciplinary case study of a river basin in south-eastern Michigan is presented. 2. The River Raisin drains an area of 2776 km2, of which some 70% is agricultural land. The upper basin consists of till and outwash, and both topography and land use/cover are diverse. The lower basin consists of fine textured lake deposits, is of low relief, and land use is primarily agricultural. 3. The River Raisin basin historically was a region of oak-savannah and wetlands. It was deforested, drained and converted to farmland during the mid-nineteenth century. Human population reached a plateau at about 1880, and then underwent a second period of growth after 1950, mainly in small urban areas. More recently, the amount of agricultural land has declined and forested land has increased, in accord with a general decline in farming activity. 4. It could be suggested that the influence of land use on stream integrity is scale-dependent. Instream habitat structure and organic matter inputs are determined primarily by local conditions such as vegetative cover at a site, whereas nutrient supply, sediment delivery, hydrology and channel characteristics are influenced by regional conditions, including landscape features and land use/cover at some distance upstream and lateral to stream sites. 5. Sediment concentrations measured during low flows were higher in areas of greater agriculture. In a comparison of two subcatchments, sediment yields were up to ten times greater in the more agricultural location, in response to similar storm events. A distributed parameter model linked to a geographical information system predicted that an increase in forested land cover would result in dramatic declines in runoff and sediment and nutrient yields. 6. Habitat quality and biotic integrity varied widely among individual stream sites in accord with patterns in land use/cover. Extent of agricultural land at the subcatchment scale was the best single predictor of local stream conditions. Local riparian vegetation was uncorrelated with overall land use and was a weak secondary predictor of habitat quality and biotic integrity. 7. Investigation of the regulatory agencies involved in land and water management in the basin revealed a complex web of overlapping political jurisdictions. Most land-use decision-making occurs at the local level of township, city or village. Unfortunately, local decision-making bodies typically lack the information and jurisdictional authority to influence up- and downstream events. 相似文献
49.
Abstract: In 1860, Stephen Hislop published a data‐rich document on the infra‐ and intertrappean strata of the Deccan Plateau of central India, along with numerous new taxa of continental and marine molluscs. His scholarship interestingly blended antiquated, contemporary, and ahead‐of‐his‐time palaeontological methods. Although his work established a completely adequate foundation upon which to build future end‐Cretaceous Deccan molluscan studies, effectively no substantive work ensued, with only incidental subsequent reference to his effort. 相似文献
50.