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271.
Halstead Katherine E. Alexander John D. Hadley Adam S. Stephens Jaime L. Yang Zhiqiang Betts Matthew G. 《Landscape Ecology》2019,34(8):1919-1935
Landscape Ecology - The relative importance of habitat fragmentation versus loss on species richness has been much debated. However, recent findings that fragmentation effects are relatively weak... 相似文献
272.
The juxtaposition of oil and gas wells against the Rocky Mountains on Colorado's Front Range provides a picture of the complicated interaction between Colorado's natural resources above and below ground. As hydraulic fracturing has increased oil and gas development—bringing jobs and money to an already highly sought after amenity‐rich area—it has also increased concerns about the impact on natural amenities, such as water quality and mountain views. Using data on housing sales between 2006 and 2014, we estimate how shale development is capitalized into housing prices in a booming market when households are in close proximity to other natural amenities. We find that shale development negatively impacts house prices, more so for houses with private water and houses that are closer to the mountains, but that competition for land along the Front Range has driven up house prices overall in the region. Our results also suggest the policy responses to shale development may differ for growing, amenity‐rich regions. 相似文献
273.
CB O''SULLIVAN AJ DART N MALIKIDES RJ RAWLINSON DR HUTCHINS DR HODGSON 《Australian veterinary journal》1999,77(8):501-503
OBJECTIVE: To evaluate nonsurgical management of type II fractures of the distal phalanx in Standardbred horses. DESIGN: Retrospective study of 48 affected horses. RESULTS: Most fractures occurred on the lateral palmar process of the left forelimb or the medial palmar process of the right forelimb; 81% of horses were considered sound enough to return to training and 63% raced. Of those returning to racing, 41% competed in > 10 races, 37% in 2 to 10 races and 22% in only 1 race. There was no difference in performance before and after fracture. Twenty-four of 25 horses had a bar shoe fitted for > 50% of the treatment phase. Of those horses returning to training without a bar shoe, 89% refractured at the same site. Sixty percent of horses returning to training with a bar shoe raced successfully. The total convalescent time, the time rested in a box and the time spelled in a paddock were similar for horses returning to racing and those that did not. The age of the horse had no effect on the ability to return to racing. CONCLUSION: The prognosis for type II fractures of the distal phalanx is guarded. It is advisable to fit a bar shoe on the horse during convalescence. Horses returning to training and racing with a bar shoe appear less likely to refracture the distal phalanx. Those horses that return to racing can perform at a level similar to that prior to fracture. 相似文献
274.
NPH HUDSON DB CHURCH J TREVENA IL NIELSEN D MAJOR DR HODGSON 《Australian veterinary journal》1999,77(8):504-508
Two Thoroughbred horses were presented with various clinical signs which included sweating, agitation, muscle twitching and synchronous diaphragmatic flutter. These signs were associated with profound hypocalcaemia. A diagnosis of primary hypoparathyroidism was made on the basis of low serum ionised calcium concentration, hyperphosphataemia and markedly reduced serum immunoreactive parathyroid hormone concentrations in the presence of normal renal function. Treatment with a combination of intravenous calcium and subsequently oral calcium, magnesium and a vitamin D analogue (dihydrotachysterol) for up to 65 days resulted in complete remission of clinical signs. Horse 1 was euthanased 12 months after the initial recognition of signs. Results of necropsy were unremarkable apart from an absence of detectable parathyroid tissue. Horse 2 returned to athletic activities while receiving only maintenance doses of oral calcium carbonate. 相似文献
275.
276.
DK Keefer SD deFrance ME Moseley JB Richardson DR Satterlee A Day-Lewis 《Science (New York, N.Y.)》1998,281(5384):1833-1835
The archaeological site of Quebrada Tacahuay, Peru, dates to 12,700 to 12,500 calibrated years before the present (10,770 to 10,530 carbon-14 years before the present). It contains some of the oldest evidence of maritime-based economic activity in the New World. Recovered materials include a hearth, lithic cutting tools and flakes, and abundant processed marine fauna, primarily seabirds and fish. Sediments below and above the occupation layer were probably generated by El Nino events, indicating that El Nino was active during the Pleistocene as well as during the early and middle Holocene. 相似文献
277.
The role of climatic variation in regulating marine populations and communities is not well understood. To improve our knowledge, the sign, amplitude, and frequency of climatic and biotic variations should be compared as a necessary first step. It is shown that there have been large interannual and interdecadal sea-surface temperature changes off the West Coast of North America during the past 80 years. Interannual anomalies appear and disappear rather suddenly and synchronously along the entire coastline. The frequency of warm events has increased since 1977. Although extensive, serial, biological observations are often incomplete, it is clear that climate-ocean variations have disturbed and changed our coastal ecosystems. 相似文献
278.
Katharina M. Hittmair DR.MED.VET. Hanna D. Vielgrader DR.MED.VET. 《Veterinary radiology & ultrasound》2000,41(6):511-515
Lameness in captive elephants is most commonly caused by pododermatitis or degenerative joint disease. Hard surfaces such as concrete, which produce a damp and cold environment, wet and muddy conditions, as well as restricted movement are the major causes of these problems. Radiography was performed in two African elephants at the Schoenbrunn Zoo in Vienna to determine the cause and extent of lameness. Various radiographic techniques are described for use in trained elephants. Low time settings were used to avoid loss of detail through movement and to minimize exposure while observing radiation safety. A 37-year-old elephant had front limb lameness due to an interdigital abscess. In radiographs of the foot an inhomogenous soft-tissue swelling without involvement of the phalanges was seen. Ultrasonography was helpful in visualizing the fluid-filled abscess. In additional joint radiographs severe degenerative joint disease was identified. A 13-year-old elephant had lameness of the hind limb. Radiographs of the hind limb from the foot to the stifle were made. Open physes and early signs of degenerative joint disease were identified on the radiographs. 相似文献
279.
280.
The relative pathogenicity of selected paratyphoids for chicks 总被引:2,自引:0,他引:2