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Extreme precipitation during Hurricane Florence, which made landfall in North Carolina in September 2018, led to breaches of hog waste lagoons, coal ash pits, and wastewater facilities. In the weeks following the storm, freshwater discharge carried pollutants, sediment, organic matter, and debris to the coastal ocean, contributing to beach closures, algae blooms, hypoxia, and other ecosystem impacts. Here, the ocean pathways of land‐sourced contaminants following Hurricane Florence are investigated using the Regional Ocean Modeling System (ROMS) with a river point source with fixed water properties from a hydrologic model (WRF‐Hydro) of the Cape Fear River Basin, North Carolina's largest watershed. Patterns of contaminant transport in the coastal ocean are quantified with a finite duration tracer release based on observed flooding of agricultural and industrial facilities. A suite of synthetic events also was simulated to investigate the sensitivity of the river plume transport pathways to river discharge and wind direction. The simulated Hurricane Florence discharge event led to westward (downcoast) transport of contaminants in a coastal current, along with intermittent storage and release of material in an offshore (bulge) or eastward (upcoast) region near the river mouth, modulated by alternating upwelling and downwelling winds. The river plume patterns led to a delayed onset and long duration of contaminants affecting beaches 100 km to the west, days to weeks after the storm. Maps of the onset and duration of hypothetical water quality hazards for a range of weather conditions may provide guidance to managers on the timing of swimming/shellfishing advisories and water quality sampling. Plain Language Summary: Hurricane Florence hit the southeastern United States in September 2018, causing historic rainfall and flooding. Floodwaters carrying contaminants traveled down rivers to the ocean, causing harmful algal blooms, beach closures, and other impacts. In the Cape Fear River Basin, North Carolina's largest watershed, open‐air lagoons used to store waste from industrial hog farming were breached, causing sewage to flow into the ocean in a coherent feature called a 'river plume' that moved in different patterns. Flooding impacts are increasing, but the movement of contaminants in river plumes following extreme events is not well understood. We used a numerical ocean model to simulate the Cape Fear River plume carrying a dye representing contaminants following Hurricane Florence. The plume initially traveled west hugging the coast due to Earth's rotation, alternately spreading east or offshore due to changes in the direction of winds blowing on the ocean. The river plume patterns led to a delayed onset and long duration of contaminants affecting beaches far down the coast, days to weeks after the storm. We also simulated several scenarios with different river discharge and winds. This information could help guide managers on when to perform water quality sampling and issue swimming or shellfishing advisories. Key Points: Pathways of land‐sourced contaminants in the aftermath of Hurricane Florence are investigated with an ocean model with hydrology sourceThe Cape Fear River plume had a westward coastal current and intermittent offshore storage modulated by wind direction and river dischargeBeaches 100 km west saw river‐sourced water quality hazards with delayed onset and long duration, from days to weeks after the storm [ABSTRACT FROM AUTHOR]

Tongue bacteria from eight adults with halitosis and five control subjects were analyzed to determine the types of bacteria present only in people with halitosis. Thirty-two species, including 13 noncultivable species, were present only in subjects with halitosis, with Solobacterium moorei present in all eight subjects with halitosis.

Actinobacillus actinomycetemcomitans is an oral pathogen that causes aggressive periodontitis as well as sometimes life-threatening, extra-oral infections. Iron regulation is thought to be important in the pathogenesis of A. actinomycetemcomitans infections and, consistent with this hypothesis, the fur gene has recently been identified and characterized in A. actinomycetemcomitans. In this study, 14 putatively Fur-regulated genes were identified by Fur titration assay (Furta) in A. actinomycetemcomitans, including afuA, dgt, eno, hemA, tbpA, recO and yfe--some of which are known to be Fur regulated in other species. A fur mutant A. actinomycetemcomitans strain was created by selecting for manganese resistance in order to study the Fur regulon. Comparisons between the fur gene sequences revealed that nucleotide 66 changed from C in the wild-type to T in the mutant strain, changing leucine to isoleucine. The fur mutant strain expressed a nonfunctional Fur protein as determined by Escherichia coli-based ferric uptake assays and Western blotting. It was also more sensitive to acid stress and expressed higher levels of minC than the wild-type strain, minC, which inhibits cell division in other bacterial species and whose regulation by iron has not been previously described, was found to be Fur regulated in A. actinomycetemcomitans by Furta, by gel shift assays, and by RT-qPCR assays for gene expression.

Smokers may heal more slowly after periodontal therapy than non-smokers. Researchers gave detailed mouth examinations to 143 people with periodontal disease who were treated with scaling and root planing. These are mechanical techniques that remove all dental plaque below the gumline. Sixty of the patients were smokers and 55 were former smokers. Current smokers healed more slowly and had greater amounts of bacteria in the pocket between the teeth and gums. Former smokers had the same healing rates as non-smokers.

Objective: Dental implants and peri-implant tissue are susceptible to disease conditions that may lead to implant loss. The objective of the present study was to describe teeth and implant surroundings as well as clinical health indices and oral microbiologic parameters. Method and Materials: A group of 83 adults (42 men and 41 women) were enrolled in the study. Clinical assessments of dental implants and contralateral natural teeth included dental plaque, gingival inflammation, and bleeding on probing. Microbiologic assessments included bacterial culture, light and phase contrast microscopy, and DNA probe hybridization for a panel of 14 target microorganisms. Clinical and microbiologic data were compared by paired t test and ANOVA. P < .05 was considered statistically significant. Results: The Plaque Index for the implants was 1.85 ± 0.47, whereas the score for natural teeth was significantly higher, 2.15 ± 0.52. Compared to the samples obtained from the dental implants, the samples from natural teeth demonstrated significantly higher total bacterial cell numbers (P < .05). Consistent with the clinical measures of dental plaque, significantly higher numbers of oral bacteria, including aerobic and anaerobic bacteria, were found in dental plaque samples from teeth (aerobic 5.648 ± 0.512, anaerobic 6.243 ± 0.535, P < .0001) compared to implants (aerobic 5.430 ± 0.541, anaerobic 5.917 ± 0.523, P < .0001). In addition, there were significantly higher numbers of anaerobic (6.243 ± 0.535 and 5.917 ± 0.523, P < .0001) than aerobic (5.648 ± 0.512 and 5.430 ± 0.541, P < .008) bacteria for samples from teeth and implants, respectively. Conclusion: Clinical and microbiologic analyses provide consistent findings that suggest differences in quantity of plaque and bacterial species between teeth and dental implants. For long-term treatment success, the importance of plaque control and oral hygiene of both periodontal and dental implant therapy is emphasized. [ABSTRACT FROM AUTHOR]