Pseudomonas aeruginosa is an opportunistic pathogen and is associated with nosocomial infections. Its ability to thrive in a broad range of environments is due to a large and diverse genome of which its accessory genome is part. The objective of this study was to characterize P. aeruginosa strains isolated from children who developed bacteremia, using pulse-field gel electrophoresis, and in terms of its genomic islands, virulence genes, multilocus sequence type, and antimicrobial susceptibility. Our results showed that P. aeruginosa strains presented the seven virulence genes: toxA, lasB, lecA, algR, plcH, phzA1, and toxR, a type IV pilin alleles (TFP) group I or II. Additionally, we detected a novel pilin and accessory gene, expanding the number of TFP alleles to group VI. All strains presented the PAPI-2 Island and the majority were exoU+ and exoS+ genotype. Ten percent of the strains were multi-drug resistant phenotype, 18% extensively drug-resistant, 68% moderately resistant and only 3% were susceptible to all the antimicrobial tested. The most prevalent acquired β-Lactamase was KPC. We identified a group of ST309 strains, as a potential high risk clone. Our finding also showed that the strains isolated from patients with bacteremia have important virulence factors involved in colonization and dissemination as: a TFP group I or II; the presence of the exoU gene within the PAPI-2 island and the presence of the exoS gene.

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Time-of-flight measurement is a critical step to per-2 form ultrasonic non-destructive testing of standing 3 trees, with direct influence on the precision of de-4 fect detection. Aiming to increase the accuracy on 5 the estimation, the characteristics of the ultrasonic 6 measurement chain should be adapted to the con-7 straints of wood testing in living condition. This 8 study focused on the excitation signal parameters, 9 such as shape, temporal duration, and frequency re-10 sponse, and then the selection of a suitable time-11 of-flight determination technique. A standing plane 12 tree was tested, placing ultrasonic receivers at four 13 different positions, with five different excitation sig-14 nals and three time-of-flight detection methods. The 15 proposed ultrasonic chain of measurement resulted in 16 high signal-to-noise ratios in received signals for all 17 configurations. A time-frequency analysis was used 18 to determine the power distribution in the frequency 19 domain, showing that only chirp signal could concen-20 trate the power around the resonant frequency of the 21 sensor. Threshold and Akaike information criterion 22 method performed similar for impulsive signals with 23 decreasing uncertainty as sensor position approached 24 to the radial direction. Those two methods failed to 25 accurate determine time-of-flight for Gaussian pulse 26 and chirp signals. Cross-correlation was only suitable 27 for the chirp signal, presenting the lower uncertainty 28 values among all configurations.

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