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31.
Comparison of the Sensitivity of Landscape-fire-succession Models to Variation in Terrain, Fuel Pattern, Climate and Weather 总被引:1,自引:0,他引:1
Geoffrey J. Cary Robert E. Keane Robert H. Gardner Sandra Lavorel Mike D. Flannigan Ian D. Davies Chao Li James M. Lenihan T. Scott Rupp Florent Mouillot 《Landscape Ecology》2006,21(1):121-137
The purpose of this study was to compare the sensitivity of modelled area burned to environmental factors across a range of
independently-developed landscape-fire-succession models. The sensitivity of area burned to variation in four factors, namely
terrain (flat, undulating and mountainous), fuel pattern (finely and coarsely clumped), climate (observed, warmer & wetter,
and warmer & drier) and weather (year-to-year variability) was determined for four existing landscape-fire-succession models
(EMBYR, FIRESCAPE, LANDSUM and SEM-LAND) and a new model implemented in the LAMOS modelling shell (LAMOS(DS)). Sensitivity
was measured as the variance in area burned explained by each of the four factors, and all of the interactions amongst them,
in a standard generalised linear modelling analysis. Modelled area burned was most sensitive to climate and variation in weather,
with four models sensitive to each of these factors and three models sensitive to their interaction. Models generally exhibited
a trend of increasing area burned from observed, through warmer and wetter, to warmer and drier climates with a 23-fold increase
in area burned, on average, from the observed to the warmer, drier climate. Area burned was sensitive to terrain for FIRESCAPE
and fuel pattern for EMBYR. These results demonstrate that the models are generally more sensitive to variation in climate
and weather as compared with terrain complexity and fuel pattern, although the sensitivity to these latter factors in a small
number of models demonstrates the importance of representing key processes. The models that represented fire ignition and
spread in a relatively complex fashion were more sensitive to changes in all four factors because they explicitly simulate
the processes that link these factors to area burned.
The US Government's and the Canadian Government's right to retain a non-exclusive, royalty-free license is acknowledged 相似文献
32.
Fabian H. Leendertz Georg Pauli Wayne Boardman Heinz Ellerbrok Sandra Junglen Boesch Christophe 《Biological conservation》2006,131(2):325-337
Until recently, the focus of great ape behavioural and ecological research has been distinct from the focus of scientists working in medical and veterinary sciences. More scientists are calling for a connection between medical and field research due to recent disease outbreaks in great apes, including Ebola, and indications of cross-transmission of Ebola and other viruses between primates and humans. A major limitation to progress is the lack of information on infectious diseases and their transmission in wild primates. Here, we present examples of successful pathogen detection in wild great apes and describe approaches and techniques that can be used in the field, focusing in particular on investigation of deaths and non-invasive sample collection. This interdisciplinary approach is providing new insights to infectious diseases of great apes and is helping to protect the health of great ape populations. This framework can also be applied to other mammals under threat from infectious diseases, including African wild dogs, seals and Tasmanian devils. In addition to providing benefits for great ape conservation, research that integrates infectious disease with primate ecology provides insights to emerging diseases in humans and the role of disease in primate evolution. 相似文献
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Sandra E. McConkey Susan Walker Cathy Adams 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(4):391-394
Two cases that involve drug compounding errors are described. One dog exhibited increased seizure activity due to a compounded, flavored phenobarbital solution that deteriorated before the expiration date provided by the compounder. The other dog developed clinical signs of hyperkalemia and bromine toxicity following a 5-fold compounding error in the concentration of potassium bromide (KBr). 相似文献
36.
Bandini LA Neto AF Pena HF Cavalcante GT Schares G Nishi SM Gennari SM 《Veterinary parasitology》2011,176(2-3):151-156
Neospora caninum is widely distributed in the world and this parasite is one of the major causes of abortion in cattle. Dogs and coyotes are definitive hosts of N. caninum and several species of domestic and wild animals are intermediate hosts. Dogs can become infected by the ingestion of tissues containing cysts and then excrete oocysts. It is not yet known whether sporulated oocysts are able to induce a patent infection in dogs, i.e. a shedding of N. caninum oocysts in feces. The objective of this study was to experimentally examine the infection of dogs by sporulated oocysts. The oocysts used in the experiment were obtained by feeding dogs with brain of buffaloes (Bubalus bubalis) positive for anti-N. caninum antibodies by indirect fluorescent antibody test (IFAT ≥200). Oocysts shed by these dogs were confirmed to be N. caninum by molecular methods and by bioassay in gerbils, and sporulated N. caninum oocysts were used for the oral infection of four dogs. The dogs were 8 weeks old and negative for antibodies to N. caninum and Toxoplasma gondii. Dogs 1 and 4 received an inoculum of 10,000 sporulated oocysts each; dog 2 an inoculum of 5000 sporulated oocysts and dog 3 received 1000 sporulated oocysts of N. caninum. The total feces excreted by these dogs were collected and examined daily for a period of 30 days. No oocysts were found in their feces. The dogs were monitored monthly for a 6-month period to observe a possible seroconversion and when this occurred the animals were eliminated from the experiment. Dogs 1 and 4 seroconverted 1 month after the infection with titer, in the IFAT, of 1600 and 800, respectively; the other two dogs presented no seroconvertion during the 6-month period. Dogs 1 and 2 were euthanized 180 days after infection and were examined for the detection of N. caninum in tissues (brain, muscle, lymph node, liver, lung, heart and bone marrow) by immunohistochemistry and PCR with negative results in both techniques. Bioassay in gerbils with brain of these dogs was also performed and again the results were negative. In conclusion, dogs infected with sporulated oocysts of N. caninum were not able to shed oocysts in feces. However, a higher dose of infection stimulated the production of antibodies against N. caninum in the dogs. 相似文献
37.
Poxviruses compromise a group of long known important pathogens including some zoonotic members affecting lifestock animals and humans. While whole genome sequence analysis started to shed light into the molecular mechanisms underlying host cell infection, viral replication as well as virulence, our understanding of poxvirus maintenance in nature and their transmission to humans is still poor. During the last two decades, reports on emerging human monkeypox outbreaks in Africa and North America, the increasing number of cowpox virus infections in cats, exotic animals and humans and cases of vaccinia virus infections in humans in South America and India reminded us that – beside the eradicated smallpox virus – there are other poxviruses that can cause harm to men. We start to learn that the host range of some poxviruses is way broader than initially thought and that mainly rodents seem to function as virus reservoir. The following review is aiming to provide an up-to-date overview on the epidemiology of zoonotic poxviruses, emphasizing orthopoxviruses. By outlining the current knowledge of poxvirus transmission, we hope to raise the awareness about modes of acquisition of infections and their proper diagnosis. 相似文献
38.
Blome S Aebischer A Lange E Hofmann M Leifer I Loeffen W Koenen F Beer M 《Veterinary microbiology》2012,158(1-2):42-59
Due to the tremendous socio-economic impact of classical swine fever (CSF) outbreaks, emergency vaccination scenarios are continuously under discussion. Unfortunately, all currently available vaccines show restrictions either in terms of marker capacities or immunogenicity. Recent research efforts were therefore directed at the design of new modified live marker vaccines. Among the most promising candidates the chimeric pestiviruses "CP7_E2alf" and "flc11" were identified. Within an international research project, these candidates were comparatively tested in challenge experiments after a single oral vaccination. Challenge infection was carried out with highly virulent CSF virus strain "Koslov", 14 or 21 days post vaccination (dpv), respectively. Safety, efficacy, and marker potential were addressed. All assessments were done in comparison with the conventional "gold standard" C-strain "Riems" vaccine. In addition to the challenge trials, multiple vaccinations with both candidates were performed to further assess their marker vaccine potential. All vaccines were safe and yielded full protection upon challenge 21 days post vaccination. Neither serological nor virological investigations showed major differences among the three vaccines. Whereas CP7_E2alf also provided clinical protection upon challenge at 14 days post vaccination, only 50% of animals vaccinated with flc11, and 83% vaccinated with C-strain "Riems" survived challenge at this time point. No marked differences were seen in protected animals. Despite the fact that all multiple-vaccinated animals stayed sero-negative in the accompanying marker test, the discriminatory assay remains a weak point due to delayed or inexistent detection of some of the vaccinated and subsequently infected animals. Nevertheless, the potential as live marker vaccines could be confirmed for both vaccine candidates. Future efforts will therefore be directed at the licensing of "Cp7_E2alf" as the first live marker vaccine for CSF. 相似文献
39.
John M David Sandra Duarte Vogel Kimberly Longo Daniel Sanchez Gregory Lawson 《Veterinary anaesthesia and analgesia》2014,41(6):654-659
ObjectiveTo investigate a topical local anesthesia technique as a means to prevent and/or diminish pain in mice in a laboratory setting associated with tail vein injections performed by personnel in training.Study designProspective, randomized experimental trial.AnimalsThirty six adult female, 23–28 g CD-1 mice from an in-house training colony. They were acclimated to routine training and handling classes.MethodsEutectic mixture of local anesthetics (EMLA) cream (2.5% lidocaine/2.5% prilocaine) or a bland ointment control (n = 18) was applied on the tail prior to intravenous injection. The injections were performed by novices, who had never attempted the procedure, and experienced personnel. All participants were blinded to treatment groups. Three injection attempts were allowed per animal. The mice were observed and scored by blinded evaluators for behavioral and physiological changes, including respiratory rate, vocalization, tail flick, and escape behaviors, during and after the injection.ResultsThis study demonstrates that aversive behaviors induced by lateral tail vein injection were not changed by the preemptive application of EMLA cream. The aversive behaviors associated with lateral tail vein injection were significantly affected by the number of injection attempts and the individual's experience level.Conclusions and clinical relevanceTopical EMLA cream did not reduce signs of aversive reaction to tail vein injection and thus we did not find support for its use in mouse training programs for tail vein injections. 相似文献
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