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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... 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.
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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... 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 (3500-6700 å) is currently measuring ion or neutral velocities and temperatures at the Alcator C-Mod tokamak. The ion velocities are measured through... 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 outboard midplane region of ohmic L-mode plasmas have been characterized using Gas-Puff-Imaging measurements. Poloidal resolution was provided by... 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 provide a device that can be quickly positioned and removed by the subject. This not only prevents cap dislodgment during sampling but also... 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 ...
Although cardiorespiratory fitness (CRF) is prognostic in older adults, the effect of CRF during early adulthood on long-term cardiovascular structure, function, and prognosis is less clear. To examine whether CRF in young adults is... more
Although cardiorespiratory fitness (CRF) is prognostic in older adults, the effect of CRF during early adulthood on long-term cardiovascular structure, function, and prognosis is less clear. To examine whether CRF in young adults is associated with long-term clinical outcome and subclinical cardiovascular disease (CVD). Prospective study of 4872 US adults aged 18 to 30 years who underwent treadmill exercise testing at a baseline study visit from March 25, 1985, to June 7, 1986, and 2472 individuals who underwent a second treadmill test 7 years later. Median follow-up was 26.9 years, with assessment of obesity, left ventricular mass and strain, coronary artery calcification (CAC), and vital status and incident CVD. Follow-up was complete on August 31, 2011, and data were analyzed from recruitment through the end of follow-up. The presence of CAC was assessed by computed tomography at years 15 (2000-2001), 20 (2005-2006), and 25 (2010-2011), and left ventricular mass was assessed at years 5 (1990-1991) and 25 (with global longitudinal strain). Incident CVD and all-cause mortality were adjudicated. Of the 4872 individuals, 273 (5.6%) died and 193 (4.0%) experienced CVD events during follow-up. After comprehensive adjustment, each additional minute of baseline exercise test duration was associated with a 15% lower hazard of death (hazard ratio [HR], 0.85; 95% CI, 0.80-0.91; P < .001) and a 12% lower hazard of CVD (HR, 0.88; 95% CI, 0.81-0.96; P = .002). Higher levels of baseline CRF were associated with significantly lower left ventricular mass index (β = -0.24; 95% CI, -0.45 to -0.03; P = .02) and significantly better lobal longitudinal strain (β = -0.09; 95% CI, -0.14 to -0.05; P < .001) at year 25. Fitness was not associated with CAC. A 1-minute reduction in fitness by year 7 was associated with 21% and 20% increased hazards of death (HR, 1.21; 95% CI, 1.07-1.37; P = .002) and CVD (HR, 1.20; 95% CI, 1.06-1.37; P = .006), respectively, along with a more impaired strain (β = 0.15; 95% CI, 0.08-0.23; P < .001). No association between change in fitness and CAC was found. Higher levels of fitness at baseline and improvement in fitness early in adulthood are favorably associated with lower risks for CVD and mortality. Fitness and changes in fitness are associated with myocardial hypertrophy and dysfunction but not CAC. Regular efforts to…
The role of coronary artery calcium (CAC) as a screening tool for cardiovascular disease (CVD) risk in African Americans (AAs) is unclear. We compared the diagnostic accuracy for CVD prevalence using the CAC score and the Framingham Risk... more
The role of coronary artery calcium (CAC) as a screening tool for cardiovascular disease (CVD) risk in African Americans (AAs) is unclear. We compared the diagnostic accuracy for CVD prevalence using the CAC score and the Framingham Risk Score (FRS) in an adult population of AAs. CAC was measured in 2944 participants AAs. Approximately 8% of this cohort had known CVD defined as prior myocardial infarction, stroke, percutaneous coronary intervention, coronary artery bypass grafting and peripheral artery disease. Logistic regression, receiver operating characteristic (ROC) and net reclassification index (NRI) analysis were used adjusting for age, gender, systolic blood pressure (SBP), total and high-density lipoprotein (HDL) cholesterol, smoking status, diabetes mellitus (DM), body mass index (BMI), blood pressure medication and statin use. Participants with prevalent clinical CVD and DM were classified as high FRS risk. The mean age of participants was 60 years, 65% were females, 26% had DM, 50% were obese and 30% were current or former smokers. Prevalent CVD was associated with older age, higher SBP, lower HDL and total cholesterol, and higher CAC. The prevalence of CAC was 83% in participants with prevalent CVD and 45% in those without CVD. CAC was independently associated with prevalent CVD in our multivariable model [OR (95% CI): 1.22 (1.12-1.32), p< 0.0001]. In ROC analysis, CAC improved the diagnostic accuracy (c statistic) of the FRS from 0.617 to 0.757 (p < 0.0001) for prevalent CVD. Addition of CAC to FRS resulted in net reclassification improvement of 4% for subjects with known CVD and 28.5% in those without CVD. In AAs, CAC is independently associated with prevalent CVD and improves the diagnostic accuracy of FRS for prevalent CVD by 14%. Addition of CAC improves the NRI of those with prevalent CVD by 4% and the NRI of individuals without CVD by 28.5%. Determination of CAC may be useful in CVD risk stratification in AAs.
ABSTRACT Over recent years a body of evidence has grown to suggest that East Asia is experiencing the effects of climate change. Allied to this is that coastal populations and economic assets are becoming more vulnerable to flood hazards.... more
ABSTRACT Over recent years a body of evidence has grown to suggest that East Asia is experiencing the effects of climate change. Allied to this is that coastal populations and economic assets are becoming more vulnerable to flood hazards. Flood vulnerability has increased owing to the combination of a number of human and physical variables: a) rapid coastal urban growth, b) anthropogenic changes to the environment, such as land subsidence through natural resource extraction or the removal of natural protective barriers, and c) increase in frequency and magnitude of coastal hazards associated with typhoons, storm surges, and sea-level rise. East Asia’s population is highly concentrated on low-lying coastal regions and deltaic cities are especially at risk. However, effective adaptation to climate impacts on many coasts is yet to develop. In this chapter, the drivers of coastal vulnerability are reviewed and examined in East Asia, exemplified by the Pearl River Delta (PRD), and its megacities of Guangzhou, Hong Kong and Shenzhen. The population of the PRD is expected to reach 120 million by 2050 and the delta is one of the most important economic centres in East Asia. Flood risk is substantial in the PRD, but flood-risk management appears to suffer from a lack of sufficient strategic planning to prepare for future climate extremes. Drawing on international experience of climate change adaptation and flood risk management, we suggest a path forward to develop adaptation strategies for deltaic and coastal cities in East Asia.
ABSTRACT
PURPOSE Left ventricular dysfunction is an important health concern in the African American communities. We tested the hypothesis that subclinical coronary atherosclerosis is associated with reduction in regional left ventricular function... more
PURPOSE Left ventricular dysfunction is an important health concern in the African American communities. We tested the hypothesis that subclinical coronary atherosclerosis is associated with reduction in regional left ventricular function by cardiac MRI with myocardial tagging. METHOD AND MATERIALS We used cardiac CT and MRI to measure coronary artery calcified (CAC) plaque by epicardial vessel and regional left ventricular (LV) function by myocardial tagging in 492 male and female participants of The Jackson Heart Study. Tagged images were analyzed using harmonic phase (HARP) processing for peak systolic circumferential shortening strains (ECC) at the level of the mid-ventricle and by region based on supplying coronary artery [left anterior descending (LAD), right coronary (RCA), left circumflex (LCX)]. Multivariable linear models were used to evaluate the association between peak ECC and CAC presence (CAC≥1) and absence (CAC=0) in models with other established risk factors. Expect...
Enormous distances across the vast South Pacific hinder student access to the main Fiji campus of the regional tertiary education provider, the University of the South Pacific (USP). Fortunately, USP has been a pioneer in distance... more
Enormous distances across the vast South Pacific hinder student access to the main Fiji campus of the regional tertiary education provider, the University of the South Pacific (USP). Fortunately, USP has been a pioneer in distance education (DE) and promotes multi-modal delivery of programmes. Geography has embraced DE, but doubts remain about comparability of various modes of study. This paper offers a diachronic examination of final grade performance of undergraduate physical geography students learning via three different modes. Data collected over 10 years on the pass rates of .1300 students are analysed. Various influences on student achievement are highlighted. KEY WORDS: Physical geography, higher education, South Pacific Islands, distance education
AMH is associated with menopausal timing in several studies. In contrast to prior studies that were restricted to women with regular cycles, our objective was to examine this association in women with either regular or irregular menstrual... more
AMH is associated with menopausal timing in several studies. In contrast to prior studies that were restricted to women with regular cycles, our objective was to examine this association in women with either regular or irregular menstrual cycles. CARDIA is a longitudinal, population-based study that recruited adults ages 18-30 when it began in 1985-1986. AMH was measured in serum stored in 2002-2003. Natural menopause was assessed by survey in 2005-2006 and 2010-2011. Among 716 premenopausal women, median [25th, 75th] AMH was 0.77 [0.22-2.02]ng/dL at a median age of 42 [39-45] years. Twenty-nine percent of the women (n=207) reported natural menopause during 9 years of follow up. In fully adjusted discrete-time hazard models, a 0.5ng/dL AMH decrement was associated with higher risk of menopause (p<0.001). Hazard ratios varied with time since AMH measurement. The HR (95% CI) for menopause was 8.1 (2.5-26.1) within 0-3 years and 2.3 (1.7-3.3) and 1.6 (1.3-2.1) for 3-6 and 6-9 years, respectively. When restricted to women with regular menses, results were similar (e.g., HR=6.1; 95% CI: 1.9-20.0 for 0-3 years). AMH is independently associated with natural menopause. AMH appears most useful in identifying women at risk of menopause in the near future (within 3 years of AMH measurement).
Intestinal cholesterol esterification by the enzyme acyl-CoA:cholesterol acyltransferase (ACAT) is a presumed prerequisite for cholesterol absorption. We evaluated the effect of a potent, poorly absorbed ACAT inhibitor (DuP 128:... more
Intestinal cholesterol esterification by the enzyme acyl-CoA:cholesterol acyltransferase (ACAT) is a presumed prerequisite for cholesterol absorption. We evaluated the effect of a potent, poorly absorbed ACAT inhibitor (DuP 128: N'-(2,4-difluorophenyl)-N-[5-(4,5-diphenyl-1H-imidazol-2-ylthio)pe ntyl]- N-heptylurea) on cholesterol absorption in a randomized trial. Thirty subjects received DuP 128 for 7 weeks, 10 each at 900 mg per day, 1800 mg per day, and 3600 mg per day; six subjects received placebo; and nine subjects received 1 gm neomycin twice a day. Cholesterol absorption determinations used a continuous dual isotope 14C-cholesterol and 3H-beta sitosterol method. DuP 128 (pooled doses) induced at 14.4% +/- 11.4% reduction in cholesterol absorption (p < 0.05 versus placebo): 17.6% +/- 8.4% at 900 mg, 9.1% +/- 11.4% at 1800 mg, and 17.1% +/- 12.9% at 3600 mg. Neomycin induced a 26.4% +/- 10.7% reduction (p < 0.01). After 6 weeks, neomycin reduced serum total and low-density lipoprotein cholesterol by 22.4% +/- 9.2% and 24.0% +/- 11.6%, respectively (p < 0.01 versus placebo). DuP 128 induced reductions of 3.9% +/- 11% (difference not significant) and 4.95% +/- 14.3% (p = 0.05). ACAT inhibitors limit cholesterol absorption in humans; however, the magnitude of the effect, as exemplified by DuP 128, is small.
The hypothesis that earlier menarche is associated with higher non alcoholic fatty liver disease (NAFLD) and ectopic adiposity, independent of young adult body mass index (BMI), was tested. The data from 1,214 black and white women in the... more
The hypothesis that earlier menarche is associated with higher non alcoholic fatty liver disease (NAFLD) and ectopic adiposity, independent of young adult body mass index (BMI), was tested. The data from 1,214 black and white women in the Coronary Artery Risk Development in Young Adults (CARDIA) study who reliably reported menarche age at exam years 0 and 2, who had multiple-slice abdominal computed tomography (CT) at exam year 25, and who had no known liver disease or secondary causes of steatosis were included. Women were aged 18-30 at year 0 and 43-55 at year 25. Liver attenuation, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and inter-muscular adipose tissue (IMAT) were derived from CT. NAFLD was defined as liver attenuation less than 51 Hounsfield units. One-year earlier menarche was associated with higher NAFLD (RR = 1.15; 95% CI: 1.07, 1.24), and VAT (6.7 cc; 95% CI: 4.3, 9.0 cc), IMAT (1.0 cc; 95% CI: 0.6, 1.4 cc), and SAT (19.6 cc; 95% CI: 13.2, 26.0 cc...
... Ami Chand, Pradeep Chand, Douglas Clark, Antoine DeBiran, Finiasi Faga, Sitaram Garimella, Robert Gouyet, Tetsushi Hidaka, Kei Kawai, Ray Kostaschuk, Ravind Kumar, Riteshni Lata, Simon McGree, Rajendra Prasad, Rishi Raj, Nick... more
... Ami Chand, Pradeep Chand, Douglas Clark, Antoine DeBiran, Finiasi Faga, Sitaram Garimella, Robert Gouyet, Tetsushi Hidaka, Kei Kawai, Ray Kostaschuk, Ravind Kumar, Riteshni Lata, Simon McGree, Rajendra Prasad, Rishi Raj, Nick Rollings, Roshni Singh, Randy Thaman ...

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