203 research outputs found
Performance praxis and oral tradition
Definitions of oral tradition among performance studies scholars in the National Communication Association are broad, as scholars use performance theory and practice to understand such oral traditions as personal, family, and folk narratives, and complex genres such as African American stepping, which involve oral narratives, songs, and synchronized percussive movement (Pollock 1999; Langellier and Petersen 2004; Fine 2003). While not all personal narratives have entered "tradition" by being transmitted through time from one generation to another, they usually enact cultural values and norms, and in that sense, could be called traditional. Using performance praxis to teach oral tradition provides a dynamic way to restore social contexts and aesthetic form to the incomplete printed records of oral traditions.Not
Microstructure mixing observations and finescale parameterizations in the Beaufort Sea
Author Posting. Β© American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 51(1), (2021): 19-35, https://doi.org/10.1175/JPO-D-19-0233.1.In the Beaufort Sea in September of 2015, concurrent mooring and microstructure observations were used to assess dissipation rates in the vicinity of 72Β°35β²N, 145Β°1β²W. Microstructure measurements from a free-falling profiler survey showed very low [O(10β10) W kgβ1] turbulent kinetic energy dissipation rates Ξ΅. A finescale parameterization based on both shear and strain measurements was applied to estimate the ratio of shear to strain RΟ and Ξ΅ at the mooring location, and a strain-based parameterization was applied to the microstructure survey (which occurred approximately 100 km away from the mooring site) for direct comparison with microstructure results. The finescale parameterization worked well, with discrepancies ranging from a factor of 1β2.5 depending on depth. The largest discrepancies occurred at depths with high shear. Mean RΟ was 17, and RΟ showed high variability with values ranging from 3 to 50 over 8 days. Observed Ξ΅ was slightly elevated (factor of 2β3 compared with a later survey of 11 profiles taken over 3 h) from 25 to 125 m following a wind event which occurred at the beginning of the mooring deployment, reaching a maximum of Ξ΅= 6 Γ 10β10 W kgβ1 at 30-m depth. Velocity signals associated with near-inertial waves (NIWs) were observed at depths greater than 200 m, where the Atlantic Water mass represents a reservoir of oceanic heat. However, no evidence of elevated Ξ΅ or heat fluxes was observed in association with NIWs at these depths in either the microstructure survey or the finescale parameterization estimates.This work was supported by NSF Grants PLR 14-56705 and PLR-1303791 and by NSF Graduate Research Fellowship Grant DGE-1650112
Chlamydia Prevalence Trends among Women and Men Entering the National Job Training Program from 1990 Through 2012
Background Evaluating chlamydia prevalence trends from sentinel surveillance is important for understanding population disease burden over time. However, prevalence trend estimates from surveillance data may be misleading if they do not account for changes in risk profiles of individuals who are screened (case mix) and changing performance of the screening tests used. Methods We analyzed chlamydia screening data from a sentinel surveillance population of 389,555 young women (1990-2012) and 303,699 young men (2003-2012) entering the US National Job Training Program. This period follows the introduction of national chlamydia screening programs designed to prevent transmission and reduce population disease burden. After ruling out bias due to case mix, we used an expectation-maximization-based maximum likelihood approach to account for measurement error from changing screening tests, and generated minimally biased long-term chlamydia prevalence trend estimates among youth and young adults in this sentinel surveillance population. Results Adjusted chlamydia prevalence among women was high throughout the study period, but fell from 20% in 1990 to 12% in 2003, and remained between 12% and 14% through 2012. Adjusted prevalence among men was steady throughout the study period at approximately 7%. For both women and men, adjusted prevalence was highest among Black and American Indian youth and young adults, and in the Southern and Midwestern regions of the United States throughout the study period. Conclusions Our minimally biased trend estimates provide support for an initial decrease in chlamydia prevalence among women soon after the introduction of national chlamydia screening programs. Constant chlamydia prevalence in more recent years suggests that screening may not be sufficient to further reduce chlamydia prevalence among high-risk youth and young adults
Double diffusion, shear instabilities, and heat impacts of a pacific summer water intrusion in the Beaufort Sea
Β© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Fine, E., MacKinnon, J., Alford, M., Middleton, L., Taylor, J., Mickett, J., Cole, S., Couto, N., Boyer, A., & Peacock, T. Double diffusion, shear instabilities, and heat impacts of a pacific summer water intrusion in the Beaufort Sea. Journal of Physical Oceanography, 52(2), (2022): 189β203, https://doi.org/10.1175/jpo-d-21-0074.1.Pacific Summer Water eddies and intrusions transport heat and salt from boundary regions into the western Arctic basin. Here we examine concurrent effects of lateral stirring and vertical mixing using microstructure data collected within a Pacific Summer Water intrusion with a length scale of βΌ20 km. This intrusion was characterized by complex thermohaline structure in which warm Pacific Summer Water interleaved in alternating layers of O(1) m thickness with cooler water, due to lateral stirring and intrusive processes. Along interfaces between warm/salty and cold/freshwater masses, the density ratio was favorable to double-diffusive processes. The rate of dissipation of turbulent kinetic energy (Ξ΅) was elevated along the interleaving surfaces, with values up to 3 Γ 10β8 W kgβ1 compared to background Ξ΅ of less than 10β9 W kgβ1. Based on the distribution of Ξ΅ as a function of density ratio RΟ, we conclude that double-diffusive convection is largely responsible for the elevated Ξ΅ observed over the survey. The lateral processes that created the layered thermohaline structure resulted in vertical thermohaline gradients susceptible to double-diffusive convection, resulting in upward vertical heat fluxes. Bulk vertical heat fluxes above the intrusion are estimated in the range of 0.2β1 W mβ2, with the localized flux above the uppermost warm layer elevated to 2β10 W mβ2. Lateral fluxes are much larger, estimated between 1000 and 5000 W mβ2, and set an overall decay rate for the intrusion of 1β5 years.This work was supported by ONR Grant N00014-16-1-2378 and NSF Grants PLR 14-56705 and PLR-1303791, NSF Graduate Research Fellowship Grant DGE-1650112, as well as by the Postdoctoral Scholar Program at Woods Hole Oceanographic Institution, with funding provided by the Weston Howland Jr. Postdoctoral Scholarship
Prospecting environmental mycobacteria: combined molecular approaches reveal unprecedented diversity
Background: Environmental mycobacteria (EM) include species commonly found in various terrestrial and aquatic environments, encompassing animal and human pathogens in addition to saprophytes. Approximately 150 EM species can be separated into fast and slow growers based on sequence and copy number differences of their 16S rRNA genes. Cultivation methods are not appropriate for diversity studies; few studies have investigated EM diversity in soil despite their importance as potential reservoirs of pathogens and their hypothesized role in masking or blocking M. bovis BCG vaccine.
Methods: We report here the development, optimization and validation of molecular assays targeting the 16S rRNA gene to assess diversity and prevalence of fast and slow growing EM in representative soils from semi tropical and temperate areas. New primer sets were designed also to target uniquely slow growing mycobacteria and used with PCR-DGGE, tag-encoded Titanium amplicon pyrosequencing and quantitative PCR.
Results: PCR-DGGE and pyrosequencing provided a consensus of EM diversity; for example, a high abundance of pyrosequencing reads and DGGE bands corresponded to M. moriokaense, M. colombiense and M. riyadhense. As expected pyrosequencing provided more comprehensive information; additional prevalent species included M. chlorophenolicum, M. neglectum, M. gordonae, M. aemonae. Prevalence of the total Mycobacterium genus in the soil samples ranged from 2.3Γ107 to 2.7Γ108 gene targets gβ1; slow growers prevalence from 2.9Γ105 to 1.2Γ107 cells gβ1.
Conclusions: This combined molecular approach enabled an unprecedented qualitative and quantitative assessment of EM across soil samples. Good concordance was found between methods and the bioinformatics analysis was validated by random resampling. Sequences from most pathogenic groups associated with slow growth were identified in extenso in all soils tested with a specific assay, allowing to unmask them from the Mycobacterium whole genus, in which, as minority members, they would have remained undetected
When to update COVID-19 vaccine composition
Vaccines against different SARS-CoV-2 variants have been approved, but continued surveillance is needed to determine when the antigen composition of vaccines should be updated, together with clinical studies to assess vaccine efficacy
Time to Osteoporosis and Major Fracture in Older Men
For older men who undergo bone mineral density (BMD) testing, the optimal osteoporosis screening schedule is unknown. Time-to-disease estimates are necessary to inform screening intervals
Time to Osteoporosis and Major Fracture in Older Men
For older men who undergo bone mineral density (BMD) testing, the optimal osteoporosis screening schedule is unknown. Time-to-disease estimates are necessary to inform screening intervals
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