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1.
D. P. Sleeman J. Davenport S. J. More T. A. Clegg J. D. Collins S. W. Martin D. H. Williams J. M. Griffin I. O’Boyle 《European Journal of Wildlife Research》2009,55(4):333-344
In Ireland, the badger Meles meles L is a reservoir species for Mycobacterium bovis and, as such, contributes to the maintenance of bovine tuberculosis in cattle. A previous estimate of the badger population
in the Republic was 200,000 badgers. In the current study, we obtained data on badger numbers from a large-scale badger removal
project (the Four-Area project). The removal areas of the Four-Area Project were surrounded by barriers (either water or buffer
areas where removals were also conducted) to prevent badger immigration. Within these areas, a grid of 0.25 km2 was created within which we knew the badger numbers and habitat types (based on Corine data). Associations between badger
numbers and habitat type were investigated using negative binomial modeling. Extrapolations from the model yielded an estimated
badger population in the Republic of approximately 84,000 badgers. The implications of these findings are discussed. 相似文献
2.
Bruyère F Melen-Lamalle L Blacher S Roland G Thiry M Moons L Frankenne F Carmeliet P Alitalo K Libert C Sleeman JP Foidart JM Noël A 《Nature methods》2008,5(5):431-437
A lack of appropriate in vitro models of three-dimensional lymph vessel growth hampers the study of lymphangiogenesis. We developed a lymphatic ring assay--a potent, reproducible and quantifiable three-dimensional culture system for lymphatic endothelial cells that reproduces spreading of endothelial cells from a pre-existing vessel, cell proliferation, migration and differentiation into capillaries. In the assay, mouse thoracic duct fragments are embedded in a collagen gel, leading to the formation of lumen-containing lymphatic capillaries, which we assessed by electron microscopy and immunostaining. We developed a computerized method to quantify the lymphatic network. By applying this model to gene-deficient mice, we found evidence for involvement of the matrix metalloproteinase, MMP-2, in lymphangiogenesis. The lymphatic ring assay bridges the gap between two-dimensional in vitro models and in vivo models of lymphangiogenesis, can be used to exploit the potential of existing transgenic mouse models, and rapidly identify regulators of lymphangiogenesis. 相似文献
3.
A retrospective study was conducted to identify causes of morbidity and mortality of free-living raptors in northeast Colorado and the surrounding areas of Nebraska and Wyoming. The study included 409 raptors, representing 23 species, admitted to the Colorado State University Veterinary Teaching Hospital, Fort Collins, Colorado, USA, from 1995 to 1998. Causes of morbidity and mortality were identified as trauma (66.3%), orphaned young (15.6%), unknown (9.0%), infectious disease (4.4%), metabolic and nutritional disease (2.2%), toxicosis (2.0%), and degenerative disease (0.5%). Trauma was the most frequent cause of morbidity and mortality for all species and during all seasons. 相似文献
4.
Background
In addition to known protein-coding genes, large amounts of apparently non-coding sequence are conserved between the human and mouse genomes. It seems reasonable to assume that these conserved regions are more likely to contain functional elements than less-conserved portions of the genome. 相似文献5.
D. P. Sleeman J. Davenport S. J. More T. A. Clegg J. M. Griffin I. O’Boyle 《European Journal of Wildlife Research》2009,55(3):267-278
This study’s objective was to estimate the permeability of barriers to badger immigration during the Irish Four Area project.
These barriers were at the boundaries of removal areas, where there was proactive culling of badgers. Data from the last 3 years
of the study were used. Each length of barrier was allocated a space within the removal area. These were further sub-divided
into spaces of 0–2, 2–5 km and sometimes of more than 5 km from the edge of the removal area. It is assumed that all, or some,
of the badgers caught within these spaces came across the barriers. The barriers were one of the following: external buffers,
sea, rivers and political boundaries. The total lengths of the barriers in all areas were: external buffer 128.5 km; sea 70.9 km;
river 78.6 km; political 32.2 km. We assume three scenarios: (1) all badgers caught in the final 3 years were immigrants,
(2) 75% were immigrants or (3) 50% were immigrants. We test these scenarios using chi-square tests, applying internal buffers
of 1 km to counter movements of badgers across zones. Using this approach and multivariate analysis, we found that the permeability
of barrier types varied, with sea and external buffers being the most effective barriers. The combined capture data are further
examined by the sex ratio in each range, and then the sex ratio in total. Equal numbers of males and females were found, but
the source populations were probably predominantly female. If badger management options are to achieve maximum benefits, then
the field effectiveness of such barriers needs to be understood. 相似文献
6.
Celine Scornavacca Vincent Berry Vincent Lefort Emmanuel JP Douzery Vincent Ranwez 《BMC bioinformatics》2008,9(1):413
Background
Supertree methods combine phylogenies with overlapping sets of taxa into a larger one. Topological conflicts frequently arise among source trees for methodological or biological reasons, such as long branch attraction, lateral gene transfers, gene duplication/loss or deep gene coalescence. When topological conflicts occur among source trees, liberal methods infer supertrees containing the most frequent alternative, while veto methods infer supertrees not contradicting any source tree, i.e. discard all conflicting resolutions. When the source trees host a significant number of topological conflicts or have a small taxon overlap, supertree methods of both kinds can propose poorly resolved, hence uninformative, supertrees. 相似文献7.
Epidemiologic determinants of 46 cases of aural abscessation in free-living eastern box turtles (Terrapene carolina) admitted to the Wildlife Center of Virginia (Virginia, USA) from 1991 to 2000 were evaluated. County human population density, year and season of admission, weight, and sex did not affect the risk for box turtles to develop aural abscessation. Counties with cases of aural abscessation were not randomly distributed, but rather were clustered into two multi-county regions. Geographic location was the only risk factor associated with aural abscessation in box turtles found in this study. Possible etiologies could include chronic infectious disease, malnutrition, or chronic exposure to environmental contamination with organochlorine compounds. 相似文献
8.
9.
Elizabeth Murdoch Titcomb Jessie Stevens Anne Sleeman Brandy Nelson Luke Yrastorza Adam M. Schaefer Gregory D. Bossart John S. Reif Marilyn Mazzoil 《Marine Mammal Science》2020,36(3):858-870
A previously undescribed skin abnormality, referred to as “linear skin markings” (LSM), has been identified in free-ranging common bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon, Florida (IRL). The lesions were identified during photo-identification surveys conducted from 2002 and 2015. LSM presented as distinct, parallel lines running dorso-ventrally on the torso and varied in length and width. The goals of this study were to determine (1) prevalence of the condition in IRL dolphins, (2) age and sex distribution of affected animals, (3) spatial and temporal distribution patterns, (4) duration of the condition, and (5) development of hypotheses regarding the etiology of the condition. Among 1,357 individual dolphins identified during the study period, 96 (7.0%) showed evidence of LSM. Nearly all (98.8%) cases with an established home range occurred in the northern and central regions of the IRL. The majority of cases of known sex were female (85%), of which 100% had given birth to one or more calves. The mean age of animals with LSM when first observed was 7.3 with a range of 1–20 years. The maximum observed duration of LSM was 15 years. Once observed, the condition persisted indefinitely. The etiology of LSM has not been established. 相似文献
10.
A Plonquet S Bastuji-Garin F Tahmasebi C Brisacier K Ledudal JP Farcet E Paillaud 《Immunity & ageing : I & A》2011,8(1):1-7