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High Discriminatory Power (high + discriminatory_power)
Selected AbstractsUsing habitat distribution models to evaluate large-scale landscape priorities for spatially dynamic speciesJOURNAL OF APPLIED ECOLOGY, Issue 1 2008Regan Early Summary 1Large-scale conservation planning requires the identification of priority areas in which species have a high likelihood of long-term persistence. This typically requires high spatial resolution data on species and their habitat. Such data are rarely available at a large geographical scale, so distribution modelling is often required to identify the locations of priority areas. However, distribution modelling may be difficult when a species is either not recorded, or not present, at many of the locations that are actually suitable for it. This is an inherent problem for species that exhibit metapopulation dynamics. 2Rather than basing species distribution models on species locations, we investigated the consequences of predicting the distribution of suitable habitat, and thus inferring species presence/absence. We used habitat surveys to define a vegetation category which is suitable for a threatened species that has spatially dynamic populations (the butterfly Euphydryas aurinia), and used this as the response variable in distribution models. Thus, we developed a practical strategy to obtain high resolution (1 ha) large scale conservation solutions for E. aurinia in Wales, UK. 3Habitat-based distribution models had high discriminatory power. They could generalize over a large spatial extent and on average predicted 86% of the current distribution of E. aurinia in Wales. Models based on species locations had lower discriminatory power and were poorer at generalizing throughout Wales. 4Surfaces depicting the connectivity of each grid cell were calculated for the predicted distribution of E. aurinia habitat. Connectivity surfaces provided a distance-weighted measure of the concentration of habitat in the surrounding landscape, and helped identify areas where the persistence of E. aurinia populations is expected to be highest. These identified successfully known areas of high conservation priority for E. aurinia. These connectivity surfaces allow conservation planning to take into account long-term spatial population dynamics, which would be impossible without being able to predict the species' distribution over a large spatial extent. 5Synthesis and applications. Where species location data are unsuitable for building high resolution predictive habitat distribution models, habitat data of sufficient quality can be easier to collect. We show that they can perform as well as or better than species data as a response variable. When coupled with a technique to translate distribution model predictions into landscape priority (such as connectivity calculations), we believe this approach will be a powerful tool for large-scale conservation planning. [source] An optimized, multiplexed multi-locus variable-number tandem repeat analysis system for genotyping Francisella tularensisLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2009A.J. Vogler Abstract We present a truncated, optimized, multiplexed multiple-locus variable-number tandem repeat analysis system for the molecular subtyping of Francisella tularensis that reduces time and cost requirements while retaining high discriminatory power. [source] Streptococcus suis outbreak investigation using multiple-locus variable tandem repeat number analysisMICROBIOLOGY AND IMMUNOLOGY, Issue 7 2010Wei Li ABSTRACT Two outbreaks of Streptococcus suis ST7 occurred in humans in 1998 and 2005 in China. PFGE of chromosome restriction fragments found all ST7 isolates to be indistinguishable. Due to the genetic homogeneity of ST7 isolates, development of a rapid sub-typing method with high discriminatory power for ST7 isolates is required. In this study, a novel method, MLVA, was developed to type S. suis serotype 2 strains. Further, this method was used to analyze outbreak-associated ST7 strains in China. A total of 144 ST7 S. suis isolates were sub-typed into 34 MLVA types. Among these, eight isolates from the 1998 outbreak were sub-typed into five MLVA types, of which four MLVA types were also detected in Sichuan in 2005. These data indicate that the pathogens responsible for the two outbreaks had the same origin. In addition, some observations also provided molecular evidence for the transmission route, possibly indicating that the MLVA method has usefulness in epidemiology. The developed MLVA scheme for S. suis has greater discriminative power than PFGE. The method described here may be useful for identifying the source of S. suis infection and monitoring its spread. [source] Molecular typing of Aspergillus speciesMYCOSES, Issue 6 2008H. A. De Valk Summary Aspergillus species are widely distributed fungi that release large amounts of airborne conidia, which are dispersed in the environment. Several Aspergillus species have been described as human pathogens. Molecular techniques have been developed to investigate the epidemiological relation between environmental and clinical isolates. Several typing methods have been described for Aspergillus species, most of them with reference to Aspergillus fumigatus. Here, we summarise all the different available molecular typing techniques for Aspergillus. The performance of these techniques is evaluated with respect to their practical feasibility, and their interpretation and discriminatory power assessed. For A. fumigatus isolates, a large extent of genetic variability is demonstrated and therefore fingerprinting techniques with high discriminatory power and high reproducibility are required for this species. Afut1-restriction fragment length polymorphism and microsatellite typing showed the highest discriminatory power. In addition, the microsatellites show excellent reproducibility. Other typing techniques are still useful for smaller epidemiological problems and for less well-equipped laboratories. [source] | ||||||||||