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11.
Johnson Chris J. Boyce Mark S. Mulders Robert Gunn Anne Gau Rob J. Cluff H. Dean Case Ray L. 《Landscape Ecology》2004,19(8):869-882
Multiscale analyses are widely employed for wildlife-habitat studies. In most cases, however, each scale is considered discrete and little emphasis is placed on incorporating or measuring the responses of wildlife to resources across multiple scales. We modeled the responses of three Arctic wildlife species to vegetative resources distributed at two spatial scales: patches and collections of patches aggregated across a regional area. We defined a patch as a single or homogeneous collection of pixels representing 1 of 10 unique vegetation types. We employed a spatial pattern technique, three-term local quadrat variance, to quantify the distribution of patches at a larger regional scale. We used the distance at which the variance for each of 10 vegetation types peaked to define a moving window for calculating the density of patches. When measures of vegetation patch and density were applied to resource selection functions, the most parsimonious models for wolves and grizzly bears included covariates recorded at both scales. Seasonal resource selection by caribou was best described using a model consisting of only regional scale covariates. Our results suggest that for some species and environments simple patch-scale models may not capture the full range of spatial variation in resources to which wildlife may respond. For mobile animals that range across heterogeneous areas we recommend selection models that integrate resources occurring at a number of spatial scales. Patch density is a simple technique for representing such higher-order spatial patterns. 相似文献
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Federica Morandi DVM MS Gregory B. Daniel DVM MS Rebecca E. Gompf DVM MS Anne Bahr DVM MS 《Veterinary radiology & ultrasound》2004,45(2):97-102
Diagnosing right-to-left congenital cardiac shunts can be difficult. Cardiac catheterization and angiocardiography represent the traditional gold standard for diagnosis, but they are invasive. Nuclear scintigraphy using 99mTc-macroaggregated albumin (MAA) has been employed in humans as an alternate method of diagnosis. This study reviews eight dogs presented for evaluation of a suspect right-to-left cardiac shunt that were examined using 99mTc-MAA. In all, 2-4 mCi (74-148 MBq) of reduced particle 99mTc-MAA were injected IV in a cephalic vein and static images of the whole body, including right and left lateral, dorsal, and ventral views, were acquired for 60 s and stored into a 256 x 256 x 16 matrix. Shunt fractions were calculated. One dog with radiopharmaceutical distribution limited to the lungs did not have a shunt. Seven dogs had distribution of the radiopharmaceutical outside the pulmonary capillary bed, indicating bypassing of the pulmonary capillary circulation due to a right-to-left shunt. Four dogs had 99mTc-MAA within the brain. Three dogs that did not have brain uptake, but instead had a sharp cutoff of radioactivity at the level of the front limbs and neck, were diagnosed with reverse patent ductus arteriosus (PDA). The asymmetric distribution of the radiopharmaceutical is due to the location of the shunt, distal to the brachiocephalic trunk and left subclavian artery. Shunt fractions of dogs with extrapulmonary radioactivity ranged from 40% to 59%. Nuclear scintigraphy with 99mTc-MAA is a quick alternative method of diagnosing right-to-left cardiac shunts that permits quantification of shunt fraction. Distinguishing between reverse PDA and other right-to-left shunts may be possible based on the radiopharmaceutical distribution. 相似文献
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Uses of game resources are under constant debate. One such debate focuses on hunting tourism and its contributions to rural economics. To prioritize future investment and inform policy decisions, it is necessary to identify the full economic consequences of the operation of hunting tourism companies in rural areas. However, the true economic significance of these typically small-scale companies is not apparent when examined on an industrial scale. These companies may nevertheless serve as a sustainable solution to local-scale rural challenges. In this article, the regional economic significance of hunting tourism is estimated for the East Lapland sub-region of northern Finland through the use of Computable General Equilibrium simulation models. Although these models are known to effectively evaluate short- and long-term regional economic effects of industries such as tourism, they have not previously been applied to evaluate hunting tourism. 相似文献
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Rita M. Hanel DVM DACVIM DACVECC Lee Palmer DVM MS DACVECC NREMT‐T WEMT CCRP Janice Baker DVM DACVPM Jo‐Anne Brenner BA EMT‐I EMT‐T David Dorman DVM PhD DABVT John C. Gicking DVM DACVECC Brian Gilger DVM MS DACVO DABT Cynthia M. Otto DVM PhD DACVECC DACVSMR Elizabeth Rozanski DVM DACVECC DACVIM Brian Trumpatori DVM 《Journal of Veterinary Emergency and Critical Care》2016,26(2):166-233
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