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221.
The Alexander Archipelago of Southeast Alaska encompasses over 2000 named islands that extend along 600 km of the North Pacific Coast. This review summarizes recent research on mammals of this largely unexplored region. Field inventories followed by preliminary molecular genetic analyses of selected mammals demonstrate substantial spatial structure consistent with both the dynamic geologic history of this boreal region and the highly insular landscape. New views of taxonomic diversity, biogeographic history, and contemporary population connectivity lay a framework for managing and conserving this complex biome. First, repeated Pleistocene glacial advances along the coast fragmented species, leaving clear genetic signatures and a strongly diversified fauna. Organisms recolonized the coast following deglaciation from multiple northern (Beringia), southern (West Coast and Continental) or North Pacific Coastal refugia. Several species are composed of multiple, genetically distinctive lineages (in some cases, incipient or new species) due to independent colonization histories from distinct, divergent source populations. Second, the insular landscape of the Alexander Archipelago has produced highly endemic populations. These centers of endemism should be thoughtfully managed as hotspots of lineage diversity. Until a better understanding of connectivity among these divergent populations is developed, each island should be considered an independent biological unit. Finally, industrial logging, mining, human encroachment, tourism, wildlife consumption, and invasive species should be stringently monitored and regulated with respect to impact on island endemics and ecosystems. A new conservation paradigm for the Tongass National Forest should be developed that is built around the recognition of the complexity of this incomparable island archipelago of the North Pacific. In particular, recognition of high diversity and endemism should be central to management plans. 相似文献
222.
Angelstam Per Manton Michael Elbakidze Marine Sijtsma Frans Adamescu Mihai Cristian Avni Noa Beja Pedro Bezak Peter Zyablikova Iryna Cruz Fatima Bretagnolle Vincent Díaz-Delgado Ricardo Ens Bruno Fedoriak Mariia Flaim Giovanna Gingrich Simone Lavi-Neeman Miri Medinets Sergey Melecis Viesturs Muñoz-Rojas Jose Schäckermann Jessica Stocker-Kiss Andrea Setälä Heikki Stryamets Natalie Taka Maija Tallec Gaelle Tappeiner Ulrike Törnblom Johan Yamelynets Taras 《Landscape Ecology》2019,34(7):1461-1484
Landscape Ecology - Place-based transdisciplinary research involves multiple academic disciplines and non-academic actors. Long-Term Socio-Ecological Research (LTSER) platform is one concept with ~... 相似文献
223.
- 1. The intensity of marine activities in the exclusive economic zone (EEZ) of British Columbia, Canada, was quantified.
- 2. Humans use the ocean for a multitude of purposes, many of which have a direct impact on marine life and habitat. Yet such uses are seldom assessed in an integrated fashion.
- 3. Using a GIS approach, spatial information for 39 marine activities was mapped, including commercial and recreational fishing areas, transportation and infrastructure uses, and terrestrial activities along the coast of British Columbia.
- 4. A relative scale was used to rank both the impact of marine activities and the extent of stressors beyond the location of occurrence. Limited information on the latter led to the application of three ranges of buffer distances to the data (0–1 km, 0–5 km, and 0–25 km).
- 5. The most conservative estimate (?1 km buffers) indicates at least 83% of the continental shelf and slope of British Columbia is currently being used by humans. The largest buffer assumption shows 98% of the continental shelf and slope being affected by stressors from anthropogenic activities.
- 6. This analysis provides a baseline for assessing future changes in the state of British Columbia's marine environment, and could assist in identifying areas of conservation potential.
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Shell shape and meat condition in selectively bred Sydney rock oysters,Saccostrea glomerata (Gould, 1850): The influence of grow‐out methods
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Caleb Rankin Natalie Moltschaniwskyj Jason Morton Emma Wilkie 《Aquaculture Research》2018,49(3):1189-1199
The Australian edible oyster industry has been severely impacted by disease and declining yields since the 1970s. Selective breeding of Saccostrea glomerata is one measure addressing these problems by producing fast‐growing, disease‐resistant oysters. Farmers report that selected oysters have different growth characteristics than their wild counterparts using conventional grow‐out methods. This study investigated how different grow‐out methods influence commercially valuable oyster characteristics including shell length, shape, surface growth deformities and meat condition. In June 2015, selectively bred S. glomerata spat were deployed in two estuaries (Hawkesbury River and Georges River) in NSW, Australia, using three grow‐out methods (fixed trays, Stanway cylinders and floating baskets). In November 2015, oysters were transferred among grow‐out methods to test for the effects of changing grow‐out methods on oyster growth patterns. Oysters transferred from baskets to cylinders and from trays to cylinders had, on average, deeper and wider shells, a higher meat condition and fewer shell surface deformities than oysters in other grow‐out method combinations. However, these oysters were smaller than oysters not grown in cylinders. While there were some differences in growth patterns between the estuaries, overall it was the grow‐out methods that most influenced oyster characteristics. This was attributed to differences in the amount and magnitude of movement oysters experienced in the grow‐out methods, as recorded by motion sensors. This study demonstrates how grow‐out methods can be managed to achieve desired growth trajectories and therefore improve marketability among selective bred S. glomerata. 相似文献
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Altered Serum Thyrotropin Concentrations in Dogs with Primary Hypoadrenocorticism before and during Treatment
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C.E. Reusch F. Fracassi N.S. Sieber‐Ruckstuhl W.A. Burkhardt N. Hofer‐Inteeworn C. Schuppisser M. Stirn R. Hofmann‐Lehmann F.S. Boretti 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2017,31(6):1643-1648
Background
Thyrotropin (TSH) can be increased in humans with primary hypoadrenocorticism (HA) before glucocorticoid treatment. Increase in TSH is a typical finding of primary hypothyroidism and both diseases can occur concurrently (Schmidt's syndrome); therefore, care must be taken in assessing thyroid function in untreated human patients with HA.Objective
Evaluate whether alterations in cTSH can be observed in dogs with HA in absence of primary hypothyroidism.Animals
Thirty dogs with newly diagnosed HA, and 30 dogs in which HA was suspected but excluded based on a normal ACTH stimulation test (controls) were prospectively enrolled.Methods
cTSH and T4 concentrations were determined in all dogs and at selected time points during treatment (prednisolone, fludrocortisone, or DOCP) in dogs with HA.Results
cTSH concentrations ranged from 0.01 to 2.6 ng/mL (median 0.29) and were increased in 11/30 dogs with HA; values in controls were all within the reference interval (range: 0.01–0.2 ng/dL; median 0.06). There was no difference in T4 between dogs with increased cTSH (T4 range 1.0‐2.1; median 1.3 μg/dL) compared to those with normal cTSH (T4 range 0.5‐3.4, median 1.4 μg/dL; P=0.69) and controls (T4 range 0.3‐3.8, median 1.8 μg/dL; P=0.35). After starting treatment, cTSH normalized after 2–4 weeks in 9 dogs and after 3 and 4 months in 2 without thyroxine supplementation.Conclusions and Clinical Relevance
Evaluation of thyroid function in untreated dogs with HA can lead to misdiagnosis of hypothyroidism; treatment with glucocorticoids for up to 4 months can be necessary to normalize cTSH. 相似文献229.
Lillie BN Brooks AS Keirstead ND Hayes MA 《Veterinary immunology and immunopathology》2005,108(1-2):97-110
Collagenous lectins such as mannan-binding lectins (MBLs), ficolins (FCNs), surfactant proteins A and D (SP-A, SP-D), conglutinin (CG), and related ruminant lectins are multimeric proteins with carbohydrate-binding domains aligned in a manner that facilitates binding to microbial surface polysaccharides. MBLs and FCNs are structurally related to C1q, but activate the lectin complement pathway via interaction with MBL-associated serine proteases (MASPs). MBLs, FCNs, and other collagenous lectins also bind to some host macromolecules and contribute to their removal. While there is evidence that some lectins and the lectin complement pathway are conserved in vertebrates, many differences in collagenous lectins have been observed among humans, rodents, and other vertebrates. For example, humans have only one MBL but three FCNs, whereas most other species express two FCNs and two MBLs. Bovidae express CG and other SP-D-related collectins that are not found in monogastric species. Some dysfunctions of human MBL are due to single nucleotide polymorphisms (SNPs) that affect its expression or structure and thereby increase susceptibility to some infections. Collagenous lectins have well-established roles in innate immunity to various microorganisms, so it is possible that some lectin genotypes or induced phenotypes influence resistance to some infectious or inflammatory diseases in animals. 相似文献
230.