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81.
Corey T. Callaghan Michael Slater Richard E. Major Mark Morrison John M. Martin Richard T. Kingsford 《Human Dimensions of Wildlife》2018,23(1):71-82
Avitourism is one of the faster growing subsectors of ecotourism, recognized for its economic value. Much of our current understanding of the economic value of avitourism revolves around bird festivals, migration events, or well-known birdwatching sites. Birdwatchers are a diverse group, some of whom competitively seek vagrant birds (i.e., birds outside their normal geographic range). The economic value from these unpredictable and transient birdwatching events remains poorly known. Using the travel cost method in a readily-quantifiable environment, we estimated that a vagrant Black-backed Oriole in Pennsylvania, United States of America, stimulated travel activity valued at about $223,000 USD or about $3,000 per day over 67 days. Some birdwatchers value rare birds, contributing significant time and financial resources to their viewing. Identifying such significant real economic value from avitourism can help to evaluate competing costs in debate over human land-use scenarios. 相似文献
82.
A Russell Moore Kitty Brown Cecelia Chapman Corey Broeckling 《Veterinary and comparative oncology》2023,21(3):460-468
The ratio of κ light chains to λ light chains (κ:λ) in serum is used as a biomarker of immunoglobulin secreting neoplasia in humans but has not been evaluated in dogs. A mass-spectrometry based method for determining the canine serum κ:λ was developed and used to evaluate samples from control dogs, dogs with an infectious aetiology, dogs with secretory plasma cell tumours (sPCT) and dogs with non-secretory B cell neoplasia. A human-targeted immunoturbidometric κ:λ assay and immunofixation using antisera targeting human κ light chain or λ light chain was also performed on all samples. Using whole serum samples, the MS-based κ:λ method identified 5 sPCT as κ-predominant (mean κ:λ = 3.307) and 5 sPCT as λ-predominant (mean κ:λ = 0.023) and documented differences between these groups and all other groups (p < 0.05 for all). The infectious aetiology group had a lower mean κ:λ ratio (mean κ:λ = 0.069) than control samples (mean κ:λ = 0.103, p = 0.035). Similar results were obtained when samples were enriched for proteins between 10 and 50 kDa using size exclusion chromatography, except for the statistical difference between the control and infectious aetiology group. All λ-predominant cases had only anti-human λ light chain labelling by immunofixation. Three κ-predominant cases had only anti-human κ-light chain labelling and the remaining two cases did not label with either antisera by immunofixation. The immunoturbidometric method had high analytical CV% (λ light chain CV = 13%, κ light chain CV = 50%), was unable to measure light chains in 20.5% of samples and did not distinguish groups. The data suggests that the human-targeted immunoturbidometric method would not be diagnostically useful and that the MS-derived serum κ:λ may be a useful biomarker of canine immunoglobulin secretory neoplasia which may have the ability to distinguish neoplasia from infectious causes of immunoglobulin secretion. 相似文献
83.
Kevin L. Gunnell Thomas A. Monaco Christopher A. Call Corey V. Ransom 《Strength and Conditioning Journal》2010,63(4):443-449
Interference from crested wheatgrass (Agropyron cristatum [L.] Gaertn.) seedlings is considered a major obstacle to native species establishment in rangeland ecosystems; however, estimates of interference at variable seedling densities have not been defined fully. We conducted greenhouse experiments using an addition-series design to characterize interference between crested wheatgrass and four key native species. Crested wheatgrass strongly interfered with the aboveground growth of Wyoming big sagebrush (Artemisia tridentata Nutt. subsp. wyomingensis Beetle & Young), rubber rabbitbrush (Ericameria nauseosa [Pall. ex Pursh] G. L. Nesom & Baird subsp. consimilis [Greene] G. L. Nesom & Baird), and to a lesser extent with bluebunch wheatgrass (Pseudoroegneria spicata [Pursh] A. Löve). Alternatively, bottlebrush squirreltail (Elymus elymoides [Raf.] Swezey subsp. californicus [J. G. Sm.] Barkworth) and crested wheatgrass had similar effects on each other’s growth, and interference ratios were near 1.0. Results indicate that the native grasses more readily establish in synchrony with crested wheatgrass than these native shrubs, but that once established, the native shrubs are more likely to coexist and persist with crested wheatgrass because of high niche differentiation (e.g., not limited by the same resource). Results also suggest that developing strategies to minimize interference from crested wheatgrass seedlings emerging from seed banks will enhance the establishment of native species seeded into crested wheatgrass–dominated communities. 相似文献
84.
Carlos D. Robles Corey Garza Robert A. Desharnais Megan J. Donahue 《Landscape Ecology》2010,25(5):745-759
This work examines the proposition that positive interactions among neighboring individuals within a population may produce
landscape patterns in boundary intensity. The large scale patterns emerge because the interactions favor an aggregated distribution
in the face of a potential limiting factor, and the strength of that factor varies over the landscape. The consequences of
spatially varying neighborhood processes were explored using cellular automata simulating the structure of mussel beds in
2-dimensional intertidal landscapes, each characterized by a vertical gradient of tidal immersion and a horizontal gradient
of wave energy. Running the model with and without the neighborhood processes demonstrated that the facilitating neighborhood
processes elevate intensity above that caused by the gradients, and consequently abrupt (high intensity) boundaries emerged
in the midst of gradual environmental variation. Trends generated on the 2-D landscape by the model were compared with those
in photo-mosaics of intertidal mussel beds, Mytilus californianus on rocky shores of the British Columbia. The analysis involved interpolation of boundary locations using a spatially-constrained
cluster algorithm, and then estimation of the corresponding boundary intensities using a landscape index aggregation (CLUMPY).
The general similarity between predicted and real trends in intensity over the wave energy gradients suggests that spatially
varying neighborhood processes determine much of the landscape scale variation in boundary intensity, while certain discrepancies
(e.g. a more rapid rise of observed intensities with increasing wave exposure) suggest modifications of the theory and new
empirical work. 相似文献
85.
Carolina P Sansaloni César D Petroli Jason Carling Corey J Hudson Dorothy A Steane Alexander A Myburg Dario Grattapaglia René E Vaillancourt Andrzej Kilian 《Plant methods》2010,6(1):16
Background
A number of molecular marker technologies have allowed important advances in the understanding of the genetics and evolution of Eucalyptus, a genus that includes over 700 species, some of which are used worldwide in plantation forestry. Nevertheless, the average marker density achieved with current technologies remains at the level of a few hundred markers per population. Furthermore, the transferability of markers produced with most existing technology across species and pedigrees is usually very limited. High throughput, combined with wide genome coverage and high transferability are necessary to increase the resolution, speed and utility of molecular marker technology in eucalypts. We report the development of a high-density DArT genome profiling resource and demonstrate its potential for genome-wide diversity analysis and linkage mapping in several species of Eucalyptus. 相似文献86.
Kim Friedman Matias Braccini Matthew Bjerregaard‐Walsh Ramn Bonfil Corey J. A. Bradshaw Stephen Brouwer Ian Campbell Rui Coelho Enric Corts Wetjens Dimmlich Michael G. Frisk Irene Kingma Sophy R. McCully Phillips Colman O'Criodain Denham Parker Samuel Shephard Javier Tovar‐vila Kotaro Yokawa 《Fish and Fisheries》2020,21(1):13-31
International trade in vulnerable marine species is regulated once they are listed in CITES Appendices (the Convention on International Trade in Endangered Species of Wild Fauna and Flora). Parties to the Convention submit proposal(s) 150 days prior to the CITES Conference for voting on the inclusion of new species in Appendices I and II, making a case for why CITES listing criteria are met in each case. Before the vote, Parties receive advice from (a) the Food and Agriculture Organization of the United Nations, (b) the International Union for Conservation of Nature—TRAFFIC and (c) the CITES Secretariat, among others. This paper offers an expert review of listing processes, which are the subject of much debate in fishery and environment‐protection communities, looking at two specific cases: silky shark (Carcharhinus falciformis, Carcharhinidae) and bigeye thresher shark (Alopias superciliosus, Alopiidae). The reviewers determine that the evidence made available to voting Parties is substantial, but suffers from non‐standard presentation across assessments. The best available data are not always presented or described transparently in relation to CITES criteria. An extension of the assessment period, as well as the opportunity to refute evidence, has been suggested as ways to support more informed and effective decision‐making by CITES Parties, whose composition of delegations varies greatly in their experience of marine species management and trade. Experts welcomed a greater coherence of advice between fishery and non‐fishery sources in the long term, and proposed a range of suggested improvements for the delivery of information and advice to CITES Parties. 相似文献
87.
88.
A 9 yr old neutered male mixed-breed dog was presented for an anal sac apocrine gland adenocarcinoma with regional nodal metastases. At presentation, ionized calcium was 1.91 mmol/L (NOVA Stat reference range, 1.1-1.3 mmol/L). Surgical excision of the primary tumor and metastatic lymph nodes was performed. Following surgery, symptomatic hypocalcemia was noted. Repeated ionized calcium measurements confirmed hypocalcemia, and hypercalcemia of malignancy panels suggested parathyroid gland suppression as the cause. The calcium normalized with parenteral calcium administration, but calcium later became elevated with tumor recurrence and an increase in the parathormone-related peptide. Disrupted calcium homeostasis is a potential complication following the treatment of long-standing humoral hypercalcemia of malignancy. 相似文献
89.
90.
Navjot Sodhi is best known for his advancement of tropical ecology and conservation science; however, his research origins were in fact based in the boreal forest ecosystem of Canada. Ironically, the less-studied ecosystems of the tropics have recently received much more conservation attention than northern biomes, despite the boreal forest (i) representing about one third of all remaining forest on the planet (and about 50% of the world’s remaining tracts of large, intact forest), (ii) sequestering about 30% of the Earth’s stored terrestrial carbon, and (iii) becoming increasingly fragmented with ecologically contiguous patches constituting only 44% of its entire area. These heightened threats of fragmentation and increasing fire frequency associated with expanding human industry in the boreal zone, along with climate change, mean that more international focus on the plight of the boreal ecosystem is warranted. Prior to his death, Navjot Sodhi had accepted a position at the University of Toronto where he planned to apply his keen, transdisciplinary approaches to boreal conservation science in an attempt to prevent the future destruction of planet Earth’s second ‘lung’. Although he never realised this dream, here we provide an overview and examples of how appropriate boreal forest management can be achieved. 相似文献