Numerous large carbonate boulders up to 164 tonnes in mass were investigated on the reef flat and... more Numerous large carbonate boulders up to 164 tonnes in mass were investigated on the reef flat and beaches of Makemo Atoll in the Tuamotu Archipelago of French Polynesia to reveal the past occurrence and to anticipate the future potential threat of extreme wave events, possibly generated by tropical cyclones and tsunamis. The modern reef edge and emerged mid-Holocene coastal landforms were identified as sources of boulders mobilized during extreme wave events in the past. The minimum flow velocities produced by extreme wave events were estimated to exceed 5.4–15.7 m/s at the reef edge on different parts of the atoll. Comparison of uranium–thorium ages of boulder coral fabric with written historical records indicates that two large boulders (77 and 68 tonnes) were possibly emplaced on the reef flat by a powerful cyclone in February 1878. Although most boulder dates are older than the earliest historical cyclone and tsunami records in French Polynesia, their ages concur with the following: (a) periods of " storminess " (i.e. increased cyclone activity compared to today) in the central South Pacific over the last millennium; and (b) periods of high sea-surface temperature (SST) at the Great Barrier Reef, possibly associated with higher-than-normal SSTs Pacific-wide that facilitated the generation of cyclones affecting the central South Pacific Ocean. None of the boulders on Makemo were dated younger than CE1900, implying that the last century has not experienced extreme waves of similar magnitude in the past. Nevertheless, the findings suggest that waves of comparable magnitudes to those that have transported large boulders on Makemo may recur in the Tuamotus and threaten island coasts across the central South Pacific in the future.
Journal of the American Heart Association, Jan 13, 2016
Despite evidence suggesting that early metabolic dysfunction impacts cardiovascular disease risk,... more Despite evidence suggesting that early metabolic dysfunction impacts cardiovascular disease risk, current guidelines focus on risk assessments later in life, missing early transitions in metabolic risk that may represent opportunities for averting the development of cardiovascular disease. In 4420 young adults in the Coronary Artery Risk Development in Young Adults (CARDIA) study, we defined a "metabolic" risk score based on components of the Third Report of the Adult Treatment Panel's definition of metabolic syndrome. Using latent class trajectory analysis adjusted for sex, race, and time-dependent body mass index, we identified 6 distinct metabolic trajectories over time, specified by initial and final risk: low-stable, low-worsening, high-stable, intermediate-worsening, intermediate-stable, and high-worsening. Overall, individuals gained weight over time in CARDIA with statistically but not clinically different body mass index trend over time. Dysglycemia and dyslip...
A high throughput, f/# ˜3.1, transmission grating Doppler spectrometer for visible light (3500-67... more A high throughput, f/# ˜3.1, transmission grating Doppler spectrometer for visible light (3500-6700 å) is currently measuring ion or neutral velocities and temperatures at the Alcator C-Mod tokamak. The ion velocities are measured through the Doppler shift of impurities that are present in the plasma. A line width of as small as 0.4 å(velocity sensitivity of ˜10^5 cm/s) has been measured using calibration lamps. The spectrometer is fiber optically coupled and has access to toroidal and poloidal views. A spectral survey has been done with various views of the C-Mod plasma identifying various intrinsic impurities. The first Doppler measurements of B II were recorded with ˜15 ms per frame. Additional Doppler velocity and temperature measurements in both poloidal and toroidal directions for some of the brighter impurities (e.g. He II and N III), will be given. This work is supported was performed under the auspices of the DoE by UC LLNL under contract W-7405-ENG-48 and also under DoE Coop. Agreement DE-FC02-99ER54512.
ABSTRACT The velocity fields and scale structure of the edge and near SOL turbulence in the outbo... more ABSTRACT The velocity fields and scale structure of the edge and near SOL turbulence in the outboard midplane region of ohmic L-mode plasmas have been characterized using Gas-Puff-Imaging measurements. Poloidal resolution was provided by a vertical array of views and radial profiles were constructed from slow spatial scans of the magnetic separatrix across this vertical array. The observed dispersions show a clear radial structure [1] with turbulence propagating in the ion-diamagnetic direction (1.5-2 km/s) at and outside the separatrix, and in the electron-diamagnetic direction (3.5-4 km/s) at and inside the separatrix. We have investigated the crossover region around the separatrix where for observation durations 1 ms two counter-propagating velocities are observed. We find that for shorter observation durations rapid changes in the propagation direction are revealed, with the speed of propagation remaining largely invariant. We present data on the statistical behavior of both the propagation velocities and the temporal-spatial structure of the edge turbulence.
A conventional metal cap for collecting parotid fluid has been fused to an acrylic biteblock to p... more A conventional metal cap for collecting parotid fluid has been fused to an acrylic biteblock to provide a device that can be quickly positioned and removed by the subject. This not only prevents cap dislodgment during sampling but also makes self-sampling possible in subjects who ...
Numerous large carbonate boulders up to 164 tonnes in mass were investigated on the reef flat and... more Numerous large carbonate boulders up to 164 tonnes in mass were investigated on the reef flat and beaches of Makemo Atoll in the Tuamotu Archipelago of French Polynesia to reveal the past occurrence and to anticipate the future potential threat of extreme wave events, possibly generated by tropical cyclones and tsunamis. The modern reef edge and emerged mid-Holocene coastal landforms were identified as sources of boulders mobilized during extreme wave events in the past. The minimum flow velocities produced by extreme wave events were estimated to exceed 5.4–15.7 m/s at the reef edge on different parts of the atoll. Comparison of uranium–thorium ages of boulder coral fabric with written historical records indicates that two large boulders (77 and 68 tonnes) were possibly emplaced on the reef flat by a powerful cyclone in February 1878. Although most boulder dates are older than the earliest historical cyclone and tsunami records in French Polynesia, their ages concur with the following: (a) periods of " storminess " (i.e. increased cyclone activity compared to today) in the central South Pacific over the last millennium; and (b) periods of high sea-surface temperature (SST) at the Great Barrier Reef, possibly associated with higher-than-normal SSTs Pacific-wide that facilitated the generation of cyclones affecting the central South Pacific Ocean. None of the boulders on Makemo were dated younger than CE1900, implying that the last century has not experienced extreme waves of similar magnitude in the past. Nevertheless, the findings suggest that waves of comparable magnitudes to those that have transported large boulders on Makemo may recur in the Tuamotus and threaten island coasts across the central South Pacific in the future.
Journal of the American Heart Association, Jan 13, 2016
Despite evidence suggesting that early metabolic dysfunction impacts cardiovascular disease risk,... more Despite evidence suggesting that early metabolic dysfunction impacts cardiovascular disease risk, current guidelines focus on risk assessments later in life, missing early transitions in metabolic risk that may represent opportunities for averting the development of cardiovascular disease. In 4420 young adults in the Coronary Artery Risk Development in Young Adults (CARDIA) study, we defined a "metabolic" risk score based on components of the Third Report of the Adult Treatment Panel's definition of metabolic syndrome. Using latent class trajectory analysis adjusted for sex, race, and time-dependent body mass index, we identified 6 distinct metabolic trajectories over time, specified by initial and final risk: low-stable, low-worsening, high-stable, intermediate-worsening, intermediate-stable, and high-worsening. Overall, individuals gained weight over time in CARDIA with statistically but not clinically different body mass index trend over time. Dysglycemia and dyslip...
A high throughput, f/# ˜3.1, transmission grating Doppler spectrometer for visible light (3500-67... more A high throughput, f/# ˜3.1, transmission grating Doppler spectrometer for visible light (3500-6700 å) is currently measuring ion or neutral velocities and temperatures at the Alcator C-Mod tokamak. The ion velocities are measured through the Doppler shift of impurities that are present in the plasma. A line width of as small as 0.4 å(velocity sensitivity of ˜10^5 cm/s) has been measured using calibration lamps. The spectrometer is fiber optically coupled and has access to toroidal and poloidal views. A spectral survey has been done with various views of the C-Mod plasma identifying various intrinsic impurities. The first Doppler measurements of B II were recorded with ˜15 ms per frame. Additional Doppler velocity and temperature measurements in both poloidal and toroidal directions for some of the brighter impurities (e.g. He II and N III), will be given. This work is supported was performed under the auspices of the DoE by UC LLNL under contract W-7405-ENG-48 and also under DoE Coop. Agreement DE-FC02-99ER54512.
ABSTRACT The velocity fields and scale structure of the edge and near SOL turbulence in the outbo... more ABSTRACT The velocity fields and scale structure of the edge and near SOL turbulence in the outboard midplane region of ohmic L-mode plasmas have been characterized using Gas-Puff-Imaging measurements. Poloidal resolution was provided by a vertical array of views and radial profiles were constructed from slow spatial scans of the magnetic separatrix across this vertical array. The observed dispersions show a clear radial structure [1] with turbulence propagating in the ion-diamagnetic direction (1.5-2 km/s) at and outside the separatrix, and in the electron-diamagnetic direction (3.5-4 km/s) at and inside the separatrix. We have investigated the crossover region around the separatrix where for observation durations 1 ms two counter-propagating velocities are observed. We find that for shorter observation durations rapid changes in the propagation direction are revealed, with the speed of propagation remaining largely invariant. We present data on the statistical behavior of both the propagation velocities and the temporal-spatial structure of the edge turbulence.
A conventional metal cap for collecting parotid fluid has been fused to an acrylic biteblock to p... more A conventional metal cap for collecting parotid fluid has been fused to an acrylic biteblock to provide a device that can be quickly positioned and removed by the subject. This not only prevents cap dislodgment during sampling but also makes self-sampling possible in subjects who ...
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