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Fusobacterium necrophorum causes a range of mild to life threatening infections and there is uncertainty in terms of diagnosis and treatment due to the lack of knowledge on their pathogenic mechanisms. This study characterised genomes of F. necrophorum to compare their virulence factors and investigate potential infection markers. 27 isolates of F. necrophorum from patients with pharyngotonsillitis were subjected to whole genome sequencing and compared with 42 genomes published in the NCBI database. Phylogenomics, pangemome, pan-GWAS and virulome were analysed to study strain variations with reference to virulence factors. Core genome based phylogenomic tree exhibited three clades of which Clade A belonged to F. necrophorum subsp necrophorum, clades B and C were F. necrophorum subsp funduliforme. Pan-GWAS and Pan-Virulome suggest some marker genes associated with clinical sources of isolation that needs further validation. Our study highlights some interesting features of the pathogenesis of F. necrophorum infections. Although the animal isolate genomes had some marker genes, the genomes of human isolates did not exhibit clear correlation to their clinical sources of isolation. This prompts to think of other mechanisms such as co-infections or host factors that can be involved in the pathogenesis.

A comprehensive air quality modeling project was carried out to simulate size and composition resolved airborne particulate matter concentrations in northern and central California using the pollutant concentration and meteorological data collected during the California Regional PM10/PM2.5 Air Quality Study (CRPAQS) from December 15, 2000 to January 7, 2001. Measured 24-h average PM2.5 concentrations during this time period exceeded 180 μg m−3 at Bakersfield, making it the most severe PM2.5 air quality episode ever recorded in the United States with a rigorous measurement database to support modeling. In this paper, the UCD/CIT source-oriented air quality model is used to predict the concentrations of O3, NO, NO2, CO, elemental carbon (EC), organic compounds (OC), nitrate and PM2.5 mass concentration over a 24-day period using a horizontal resolution of 4 km × 4 km to cover all of central California. This is the first extensive evaluation of an air quality model in central California using the fine spatial resolution appropriate for the mountain–valley topography of the region combined with the relatively long multi-week time scales associated with winter stagnation events. Fractional bias (FB) values were calculated at all sites on each day of the study to quantify model performance. The CO (FB = −0.5 to +0.3), O3 (FB = −0.5 to +0.25), NO (FB = −0.9 to −0.1) and NO2 (FB = 0 to +0.4) concentrations predicted by the UCD/CIT model are in general agreement with observations at most monitoring stations throughout the Valley. The predicted PM2.5 concentrations (FB = −0.5 to +0.75) generally agree with observations at Bethel Island, Sacramento, Fresno and Bakersfield spanning the entire length of the model domain. PM2.5 concentrations are over-predicted at the remote monitoring site Angiola in the central portion of the domain. Part of the over-prediction is due to excess fugitive dust emissions. CO, NO, EC and OC were all under-predicted at Angiola, indicating possible missing combustion sources in the emission inventory. The regional nitrate (FB = −1.5 to +1.25) formation dynamics were correctly reproduced by the model simulation but imperfect wind fields cause differences between the predicted vs. measured spatial distribution of nitrate during the last several days of simulation leading to the broader range of fraction bias. Overall, the results of the current study confirm the ability of the air quality model to capture the major features of a severe particulate air pollution event in northern and central California providing a foundation for future studies on source apportionment and emissions control.

Some pinniped species display aggression as male-male vocal displays only. In highly-aggressive species, outright combat is waged between males, and in other cases aggression can occur between male...

The automotive market in the UK is extremely competitive, with car buyers having much more choice now then they did ten years ago. Thus manufacturers have to be more adaptable to the needs/demands of consumers and competitors.