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1.
A leakiness index for assessing landscape function using remote sensing   总被引:2,自引:0,他引:2  
The cover, number, size, shape, spatial arrangement and orientation of vegetation patches are attributes that have been used to indicate how well landscapes function to retain, not ‘leak’, vital system resources such as rainwater and soil. We derived and tested a directional leakiness index (DLI) for this resource retention function. We used simulated landscape maps where resource flows over map surfaces were directional and where landscape patch attributes were known. Although DLI was most strongly related to patch cover, it also logically related to patch number, size, shape, arrangement and orientation. If the direction of resource flow is multi-directional, a variant of DLI, the multi-directional leakiness index (MDLI) can be used. The utility of DLI and MDLI was demonstrated by applying these indices to three Australian savanna landscapes differing in their remotely sensed vegetation patch attributes. These leakiness indices clearly positioned these three landscapes along a function-dysfunction continuum, where dysfunctional landscapes are leaky (poorly retain resources). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Detection of bovine Babesia spp. and Anaplasma marginale is based on the reading of Giemsa-stained blood or organ smears, which can have low sensitivity. Our aim was to improve the detection of bovine Babesia spp. and A. marginale by validating a multiplex PCR (mPCR). We used 466 samples of blood and/or organs of animals with signs and presumptive autopsy findings of babesiosis or anaplasmosis. The primers in our mPCR amplified the rap-1a gene region of Babesia bovis and B. bigemina, and the msp-5 region of A. marginale. We used a Bayesian model with a non-informative priori distribution for the prevalence estimate and informative priori distribution for estimation of sensitivity and specificity. The sensitivity and specificity for smear detection of Babesia spp. were 68.6% and 99.1%, and for A. marginale 85.6% and 98.8%, respectively. Sensitivity and specificity for mPCR detection for Babesia spp. were 94.2% and 97.1%, and for A. marginale 95.2% and 92.7%, respectively. Our mPCR had good accuracy in detecting Babesia spp. and A. marginale, and would be a reliable test for veterinarians to choose the correct treatment for each agent.  相似文献   
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A 14-year-old neutered male domestic shorthaired cat was presented to the University Veterinary Centre Sydney for evaluation and treatment of dental disease. This cat developed an unusual bradyarrhythmia under anaesthesia. The possible causes and treatment of the dysrythmia are discussed.  相似文献   
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Salinity and sodicity effects on respiration and microbial biomass of soil   总被引:2,自引:2,他引:2  
An understanding of the effects of salinity and sodicity on soil carbon (C) stocks and fluxes is critical in environmental management, as the areal extents of salinity and sodicity are predicted to increase. The effects of salinity and sodicity on the soil microbial biomass (SMB) and soil respiration were assessed over 12weeks under controlled conditions by subjecting disturbed soil samples from a vegetated soil profile to leaching with one of six salt solutions; a combination of low-salinity (0.5dSm−1), mid-salinity (10dSm−1), or high-salinity (30dSm−1), with either low-sodicity (sodium adsorption ratio, SAR, 1), or high-sodicity (SAR 30) to give six treatments: control (low-salinity low-sodicity); low-salinity high-sodicity; mid-salinity low-sodicity; mid-salinity high-sodicity; high-salinity low-sodicity; and high-salinity high-sodicity. Soil respiration rate was highest (56–80mg CO2-C kg−1 soil) in the low-salinity treatments and lowest (1–5mg CO2-C kg−1 soil) in the mid-salinity treatments, while the SMB was highest in the high-salinity treatments (459–565mg kg−1 soil) and lowest in the low-salinity treatments (158–172mg kg−1 soil). This was attributed to increased substrate availability with high salt concentrations through either increased dispersion of soil aggregates or dissolution or hydrolysis of soil organic matter, which may offset some of the stresses placed on the microbial population from high salt concentrations. The apparent disparity in trends in respiration and the SMB may be due to an induced shift in the microbial population, from one dominated by more active microorganisms to one dominated by less active microorganisms.  相似文献   
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Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta‐analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no‐take area. CPUE of both target species and the marketable catch increased gradually by 2–4% per year over a long time period (at least 30 years). The influence of the size of the no‐take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no‐take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no‐take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs.  相似文献   
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Phytomedicines are becoming more popular all over the world. Denture stomatitis (DS) presents as an inflammatory reaction in denture-bearing patients, under maxillary prosthesis with Candida albicans being the principal etiological agent. Many different methods of treatment for DS have been observed. The effects of the main medicinal plants claimed to be useful as antifungal agents in the treatment of DS are reviewed. Herbal remedies that have shown potential promise are mentioned, although much research is still required.  相似文献   
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The study of anatomy is important to accomplish any kind of surgical and medical procedure and to understand the physiology and diseases of animals. It is no different in veterinary dentistry. The study of oral anatomy helps the veterinarian to accomplish any kind of surgical procedure more quickly and with less damage to tissues, especially in cases of major oral surgery. In fact, under-standing the anatomy is easier when this knowledge is acquired directly, with surgical application. This article describes the essentials of the oral anatomy of the dog and cat, correlating this knowledge with the dental procedures to be used by veterinarians as a guide.  相似文献   
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