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1.
Monica T. Engel Jerry J. Vaske Alistair J. Bath Silvio Marchini 《Human Dimensions of Wildlife》2016,21(5):427-444
Jaguars and pumas are threatened species in Brazil’s Atlantic Forest, especially at the borders of protected areas. This article assessed the influence of emotions, attitudes, existence value, and agency credibility on acceptability of big cats among rural residents living adjacent to two protected areas in this forest. Data from self-administrated questionnaires (n = 326) indicated those with positive attitudes toward big cats (β = .28, p < .001), those who valued the existence of big cats (β = .14, p < .05), those who would feel sorrow if big cats disappeared (β = .21, p < .001), and those who considered the managing agency as credible (β = .16, p = .002) were more accepting of big cats. The model provided theoretical and practical insights into large carnivore conservation. For example, given the significance of agency credibility, a positive relationship between park authorities and residents is crucial for big cat conservation. 相似文献
2.
Loader JI Hawkes AD Beuzenberg V Jensen DJ Cooney JM Wilkins AL Fitzgerald JM Briggs LR Miles CO 《Journal of agricultural and food chemistry》2007,55(26):11093-11100
Yessotoxins from a large-scale culture (226 L) of Protoceratium reticulatum strain CAWD129 were harvested by filtration followed by solid-phase extraction. The extract was purified by column chromatography over basic alumina and reverse-phase flash chromatography to afford pure yessotoxin (193 mg). Isolation of yessotoxin was greatly facilitated by selection of a strain which did not produce analogues that interfered with yessotoxin isolation. In addition to yessotoxin, numerous minor yessotoxins were detected by LC-MS in other fractions. From one of these, an early eluting minor analogue with the same molecular weight as yessotoxin and a similar mass spectrometric fragmentation pattern was isolated. This analogue was identified by NMR and mass spectrometry as a novel yessotoxin analogue containing a furan ring in the side chain. This finding reveals biosynthetic flexibility of the yessotoxin pathway in P. reticulatum and confirms earlier findings of production of many minor yessotoxin analogues by this alga. Production of these analogues appeared to be a constitutive trait of P. reticulatum CAWD129. 相似文献
3.
Climate variability and marine survival of coho salmon (Oncorhynchus kisutch) in the Oregon production area 总被引:1,自引:0,他引:1
Time series of adult recruitment for natural runs of coho salmon from the Oregon coastal region (1970–94) and marine survival of hatchery-reared coho salmon from California to Washington (1960–94) are significantly correlated with a suite of meteorological and oceanographic variables related to the biological productivity of the local coastal region. These variables include strong upwelling, cool sea surface temperature (SST), strong wind mixing, a deep and weakly stratified mixed layer, and low coastal sea level, indicating strong transport of the California Current. Principal component analysis indicates that these variables work in concert to define the dominant modes of physical variability, which appear to regulate nutrient availability and biological productivity. Multiple regression analysis suggests that coho marine survival is significantly and independently related to the dominant modes acting over this region in the periods when the coho first enter the ocean and during the overwintering/spring period prior to their spawning migration. Linear relationships provided good fits to the data and were robust, capable of predicting randomly removed portions of the data set. 相似文献
4.
Changes in attitudes toward wolves in Croatia 总被引:2,自引:0,他引:2
Against a background of an evolving wolf policy process we carried out personal structured interviews with residents of three regions within Croatian wolf range in 1999 (n = 1209) and repeated the study, using the same methodology in 2003 (n = 1172). We documented a change in public support for wolf conservation and support for control of wolves. The change was a result of a real change in attitudes and not of a change in the age structure of the sampled population. The changes were documented in the two southern regions, Lika and Dalmatia, with attitudes shifting towards a more neutral viewpoint, as there was a decrease in support for wolf conservation and a decrease in support to control wolves. It seems that different birth cohorts react differently to conservation activities. In 1999, the younger cohort groups may have been influenced more by the legal protection campaign. The older cohorts reacted more sympathetically to livestock concerns and thus held stronger negative attitudes toward wolves. Using human dimensions research as an evaluative tool can help large carnivore managers be more adaptive and thus effective in their management solutions. 相似文献
5.
Habitat fragmentation is a threat to the preservation of both terrestrial and marine biodiversity. While terrestrial systems have been well studied, relatively few studies have considered how changes to the spatial arrangement of habitats affect fauna in marine systems. In this study, sampling and manipulative experiments examined the effects of varying the size and isolation of habitat patches on the abundance of mobile invertebrates inhabiting an algal dominated rocky reef. Variation in the size of naturally occurring patches of the brown alga Sargassum linearifolium did not impact upon the abundance of any taxonomic groups, with the exception of polychaete worms, which were most abundant in small patches. When habitat patch size and isolation were manipulated, the abundance of colonising isopods increased with increasing isolation from contiguous habitat. Amphipods and ostracods colonised small patches to greater numbers than large patches. Sampling of the matrix was undertaken to examine the rarely tested assumption that the area between habitat patches is not a potential source of colonists to the habitat in question. The matrix was found to support a strikingly different community of invertebrates than did the algal habitats and thus was unlikely to be a source of colonists to isolated algal patches. The increased abundance on small and isolated patches for some taxa are inconsistent with traditional predictions of the effects of reduced habitat patch sizes and indicate that patchy landscapes should not necessarily be considered poor habitats. The variation in responses among taxonomic groups suggests that a range of patch sizes may be necessary to maintain species diversity. 相似文献
6.
Loader JI Wilkins AL Flåøyen A Ryste E Hove K 《Journal of agricultural and food chemistry》2003,51(9):2641-2645
The suitability of [2,2,4,4-(2)H(4)]sarsasapogenone (1b), [2,2,4,4-(2)H(4)]sarsasapogenin (2b), and [2,2,4,4-(2)H(4)]episarsasapogenin (3b) as isotopically labeled dosing substrates to determine the levels of free and conjugated sapogenins present in feces from sheep grazing saponin-containing plants implicated in the development of ovine heptagenous photosentization diseases was investigated. A 1:4 mixture of [2,2,4,4-(2)H(4)]sarsasapogenin (2b) and [2,2,4,4-(2)H(4)]episarsasapogenin (3b), obtained by reduction of [2,2,4,4-(2)H(4)]sarsasapogenone (1b), was found to retain 94% of incorporated deuterium, when dosed to one sheep. The recovery of the dosed mixture of genins 2b and 3b was calculated to be 85%. Considerable loss of deuterium and a lower recovery of genin material were observed when [2,2,4,4-(2)H(4)]sarsasapogenone (1b) was dosed. 相似文献
7.
Castillo UF Wilkins AL Lauren DR Smith BL Alonso-Amelot M 《Journal of agricultural and food chemistry》2003,51(9):2559-2564
Fractionation of an extract of Pteridium caudatum L. Maxon. (syn P. aquilinum L. Kuhn var. caudatum) which had earlier yielded the illudane-type sesquiterpene glucosides, ptaquiloside (1a), isoptaquiloside (1b), and caudatoside (1c) afforded a mixture containing 1a and two minor components. Preparative HPLC afforded ptaquiloside Z (1d) and a new pteroside glucoside (pteroside A2) (3e), which was identified using a combination of mass spectral and one- and two-dimensional NMR analyses. The (1)H and (13)C NMR and mass spectrometric characterization of caudatodienone (2b), an unstable dienone derived from the degradation of caudatoside (1c) in pyridine solution, and the GC-MS characterization of some pterosin-type degradation products produced by reacting this solution with cosolvents is also reported. 相似文献
8.
Dr Stephen Collier Dr Bob Bradley Faith Rosson Will Gartrell Dr Bob Bradley Alistair Webb Dr Graham Thompson Dr Elaine Cebuliak 《Australian veterinary journal》2001,79(5):320-322
Editor's note: The AVJ welcomes letters from members in all areas of the profession on matters of importance to you. Please keep them brief ‐ to meet our space constraints. Letters will be subject to minimal editing procedures. Subject to letters complying with the AVJ's legal responsibilities, they will not be censored. Nor will individuals or groups waging'‘campaigns’ be permitted to abuse these pages. If submitting a letter intended for publication, kindly identify it as such. Letters to the Editor can be sent by mail, fax or e‐mail at the contact points listed at the start of the News Section. Writers may use a pseudonym to protect their identities ‐ but must supply the Editor with verifiable names and points of contact. 相似文献
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