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This study was designed to determine the optimal intensity for verification phase testing (VP) in healthy, young adults. Thirty one young, active participants (16 females) completed a cycle ergometer graded exercise test (GXT) VO2max test and 4 VP tests at 80, 90, 100, and 105% of the maximum wattage achieved during the GXT. GXT and VP VO2max values showed a significant test x sex interaction (p = 0.02). The males elicited significantly higher VO2max values during the GXT, 80%, and 90% when compared to the 105%, (105 vs. GXT: p = 0.05, 105% vs. 80%: p &lt, 0.01, 105% vs. 90%: p = 0.02). There were no significant differences in VO2max across the tests in the females (p &gt, 0.05), 80% of the males achieved their highest VP VO2max during a submaximal VP test compared to only 37.5% of the females. A secondary study conducted showed excellent reliability (ICCs &gt, 0.90) and low variation (CVs &lt, 3%) for the 90% VP. Our findings show that a submaximal verification phase intensity is ideal for young healthy males to elicit the highest VO2max during cycle ergometer testing. For females, a range of intensities (80&ndash, 105%) produce similar VO2max values. However, the 80% VP yields an unnecessarily high time to exhaustion.

Self-transmissible and mobilizable plasmids contribute to the emergence and spread of multidrug-resistant bacteria by enabling the horizontal transfer of acquired antibiotic resistance. The objective of this study was to capture and characterize self-transmissible and mobilizable resistance plasmids from a coastal wetland impacted by urban stormwater runoff and human wastewater during the rainy season. Four plasmids were captured, two self-transmissible and two mobilizable, using both mating and enrichment approaches. Plasmid genomes, sequenced with either Illumina or PacBio platforms, revealed representatives of incompatibility groups IncP-6, IncR, IncN3, and IncF. The plasmids ranged in size from 36 to 144 kb and encoded known resistance genes for most of the major classes of antibiotics used to treat Gram-negative infections (tetracyclines, sulfonamides, β-lactams, fluoroquinolones, aminoglycosides, and amphenicols). The mobilizable IncP-6 plasmid pLNU-11 was discovered in a strain of Citrobacter freundii enriched from the wetland sediments with tetracycline and nalidixic acid, and encodes a novel AmpC-like β-lactamase (blaWDC-1), which shares less than 62% amino acid sequence identity with the PDC class of β-lactamases found in Pseudomonas aeruginosa. Although the IncR plasmid pTRE-1611 was captured by mating wetland bacteria with P. putida KT2440 as recipient, it was found to be mobilizable rather than self-transmissible. Two self-transmissible multidrug-resistance plasmids were also captured: the small (48 kb) IncN3 plasmid pTRE-131 was captured by mating wetland bacteria with Escherichia coli HY842 where it is seemed to be maintained at nearly 240 copies per cell, while the large (144 kb) IncF plasmid pTRE-2011, which was isolated from a cefotaxime-resistant environmental strain of E. coli ST744, exists at just a single copy per cell. Furthermore, pTRE-2011 bears the globally epidemic blaCTX-M-55 extended-spectrum β-lactamase downstream of ISEcp1. Our results indicate that urban coastal wetlands are reservoirs of diverse self-transmissible and mobilizable plasmids of relevance to human health.