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11.
In southwestern New Jersey during 1986 and 1987, common barn-owls and pigeons were captured on farmsteads and tested for Toxoplasma gondii antibodies by a modified direct agglutination test. In 1986, 3/28 (10.7%) adult and 0/124 nestling owls tested positive at titers of greater than or equal to 1:40. Additionally, 2/34 (5.9%) pigeons tested had T. gondii antibodies at titer of 1:320. In 1987, 9/38 (27.3%) adult and 18/80 (22.5%) nestling owls tested positive at titers of greater than or equal to 1:25; this includes 3/38 (7.9%) adult and 1/80 (1.3%) nestling owls that tested positive at a titer of 1:50. 相似文献
12.
Giardiasis in a cattery 总被引:1,自引:0,他引:1
C E Kirkpatrick J P Laczak 《Journal of the American Veterinary Medical Association》1985,187(2):161-162
Giardia sp infection was believed responsible for chronic, intermittent diarrhea in a group of 14 Persian cats. Seven of the cats were shedding Giardia sp cysts, and 6 of these cats had diarrhea at the time of fecal examination. Conversely, only 1 of 6 clinically normal cats in the group was shedding Giardia sp cysts. Cysts were not detected in feces of 2 cats with diarrhea. Cats less than or equal to 3 years old were more likely to be found shedding cysts. The parasite apparently was eradicated from the cattery by a combination of cage disinfection (1% sodium hypochlorite solution) and oral furazolidone treatment (4 mg/kg of body weight, BID for 5 consecutive days). During treatment, clinical signs resolved, and all cats remained clinically normal 2 months after treatment. 相似文献
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15.
J.B. Kirkpatrick 《Biological conservation》1983,25(2):127-134
Past work ascribing priorities for the selection of nature reserves has weighted attributes and applied formulae in a single stage process. This single application of a formula means that areas of differing priority may contain similar mixes of species, communities or habitats, and may thus lead to imbalance in representation when preservation takes place, with some previously unpreserved or poorly preserved species, communities or habitats being found in several of the new reserves, and others being absent. An iterative method that has been applied to assess priorities for the preservation of threatened species in the central east coast of Tasmania overcomes this difficulty. The area with the highest score in the initial stages of analysis is assumed to be preserved and the weightings of attributes are altered accordingly. These new weightings are applied to locate the area of next highest priority, and the process continues until predetermined preservation goals are met. 相似文献
16.
Kirkpatrick P 《Science (New York, N.Y.)》1943,97(2510):138-139
17.
Measurements of electrical conductivity at high pressure and temperature were taken on the lower mantle phase magnesiowustite with varying Fe3+ content. Although previous measurements at atmospheric pressure suggest Fe2+-Fe3+ hopping (small polaron) as the dominant conductivity mechanism, the present experiments show a change in charge transport mechanism with temperature. The lower temperature measurements are consistent with small polaron conduction, but at higher temperatures, which are more applicable to the lower mantle, a large polaron mechanism is suggested. Because these mechanisms have different temperature and compositional dependencies, this transition has important implications for extrapolation to mantle conditions. 相似文献
18.
Scherer SW Cheung J MacDonald JR Osborne LR Nakabayashi K Herbrick JA Carson AR Parker-Katiraee L Skaug J Khaja R Zhang J Hudek AK Li M Haddad M Duggan GE Fernandez BA Kanematsu E Gentles S Christopoulos CC Choufani S Kwasnicka D Zheng XH Lai Z Nusskern D Zhang Q Gu Z Lu F Zeesman S Nowaczyk MJ Teshima I Chitayat D Shuman C Weksberg R Zackai EH Grebe TA Cox SR Kirkpatrick SJ Rahman N Friedman JM Heng HH Pelicci PG Lo-Coco F Belloni E Shaffer LG Pober B Morton CC Gusella JF Bruns GA Korf BR 《Science (New York, N.Y.)》2003,300(5620):767-772
19.
Optimization by simulated annealing 总被引:29,自引:0,他引:29
There is a deep and useful connection between statistical mechanics (the behavior of systems with many degrees of freedom in thermal equilibrium at a finite temperature) and multivariate or combinatorial optimization (finding the minimum of a given function depending on many parameters). A detailed analogy with annealing in solids provides a framework for optimization of the properties of very large and complex systems. This connection to statistical mechanics exposes new information and provides an unfamiliar perspective on traditional optimization problems and methods. 相似文献
20.
T. R. Gordon S. C. Kirkpatrick B. J. Aegerter A. J. Fisher A. J. Storer D. L. Wood 《Forest Pathology》2011,41(3):227-232
Pitch canker, caused by Gibberella circinata, was discovered in California in 1986. Although initially quite damaging to Monterey pines (Pinus radiata), the severity of pitch canker has moderated in areas where the disease was first observed and some trees appear to have recovered completely. The absence of symptoms on trees that were once severely affected implies they have become more resistant to the disease. Experimental work has shown that P. radiata can manifest systemic induced resistance (SIR) in response to infection by the pitch canker pathogen and observations of disease remission may indicate that SIR is operative under natural conditions as well. As a test of this hypothesis, the susceptibility of trees in remission was assessed by inoculating them with G. circinata and recording the extent of lesion development. In addition, randomly selected trees in areas that differed in residence time of pitch canker were inoculated to determine if trees with a longer period of exposure to the pathogen were more resistant to the disease. The results of these tests showed that 89% of trees observed to be in remission sustained very limited lesion development, consistent with resistance to pitch canker. Furthermore, trees in areas where pitch canker was well established tended to be more resistant than trees in areas where the disease was of more recent occurrence. In sum, these findings support the view that SIR occurs in P. radiata and is contributing to a moderation of the impact of pitch canker under natural conditions. 相似文献