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61.
Leopards Panthera pardus are classified in the IUCN Red List as Vulnerable, primarily due to habitat loss, natural prey base depletion and exploitation caused by various anthropogenic activities. Although protected areas are important for leopard conservation, the majority of suitable leopard habitat lies beyond protected area boundaries exposing individuals to different environmental, physiological and psychosocial stressors. This study aimed to examine the suitability of five different enzyme immunoassays (EIAs) for monitoring adrenocortical function in the leopard based on faecal glucocorticoid metabolite (fGCM) analysis. After performing an adrenocorticotrophic hormone (ACTH) stimulation test and investigating the stability of fGCM post-defaecation, faeces from free-ranging leopards in a peri-urban and a conservation area were collected to investigate the potential impact of habitat variability on glucocorticoid output. An EIA measuring fGCM with a 5α-3β-11β-diol structure performed best, demonstrating a ～200%–330% increase in fGCM concentrations approximately 40 h post-ACTH administration. Concentrations of fGCM remained quite stable for up to six days post-defaecation and showed a maximum increase of 8% and a maximum decrease of 9%. Although not significantly different, overall median fGCM concentrations were 68% higher in individuals utilising the peri-urban area compared with leopards utilising the conservation area. The ranges of fGCM concentrations between sites, however, were similar. Individual median fGCM concentrations differed distinctly between free-ranging males and females, possibly linked to female reproductive status. The established method can now assist in addressing some of the issues facing local wildlife managers, conservationists and researchers tackling various aspects related to leopard conservation and management under different land-use practices. 相似文献
62.
F Hill PB Stark RT Stebbins ER Anderson HM Antia TM Brown TL Duvall DA Haber JW Harvey DH Hathaway R Howe RP Hubbard HP Jones JR Kennedy SG Korzennik AG Kosovichev JW Leibacher KG Libbrecht JA Pintar EJ Rhodes J Schou MJ Thompson S Tomczyk CG Toner R Toussaint WE Williams 《Science (New York, N.Y.)》1996,272(5266):1292-1296
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure. 相似文献