Surface hydrographic and biogeochemical properties were measured contemporaneously at high spatial density during a transit from Chesapeake Bay, across the Middle Atlantic Bight MAB and Gulf Stream ...to the Sargasso Sea near Bermuda from 28 September–2 October 1996. Discrete samples were collected for total organic carbon TOC, dissolved organic carbon DOC, total organic nitrogen TON, dissolved organic nitrogen DON, total carbon dioxide TCO
2 and alkalinity TA. Continuous measurements of temperature, salinity, fluorescence, seawater
pCO
2 and atmospheric
pCO
2 were also collected. Estuarine waters of Chesapeake Bay (salinity>20) had high
pCO
2 (>600 μatm) and high TOC (>200 μM), DOC (>190 μM) and TON (>20 μM) concentrations reflecting the riverine input of terrestrial organic matter. Low seawater
pCO
2 concentrations (∼350 μatm), compared to MAB waters (∼370–430 μatm), were observed in the offshore plume of the Chesapeake. High TOC, TON, TCO
2 and alkalinity concentrations were observed within a filament of low salinity shelf water abutting the western wall of the Gulf Stream. These filaments are apparently advected off the shelf near Cape Hatteras and subducted beneath the Gulf Stream. We estimate that this process will export shelf organic carbon into the North Atlantic basin at a rate ∼3–31×10
12 g C year
−1, depending on the amount of water advected off the shelf.
•MS3DATA predicts multiphase flow characteristics using simulation data.•Bubble statistics computed using novel detection and tracking algorithm.•Algorithm capabilities exemplified by application to ...bubbling fluidized bed case.•3D detection accurately captures small bubbles, slugs and their azimuthal velocity.•Algorithm is scalable and computes high-resolution statistics with insignificant cost.
Bubble dynamics play a critical role in the hydrodynamics of fluidized beds and significantly affect reactor performance. In this study, MS3DATA (Multiphase-flow Statistics using 3D Detection And Tracking Algorithm) is developed, validated and applied to numerical simulations of large-scale fluidized beds. Using this algorithm, bubbles are detected using void fraction data from simulations and are completely characterized by their size, shape and location while their velocities are computed by tracking bubbles across successive time frames. A detailed analysis of 2D (across vertical sections) and 3D bubble statistics using 3D simulations of lab-scale (diameter 14.5cm) and pilot-scale bed (diameter 30cm) is presented and it is shown that the former (a) under-predicts sizes of larger bubbles, (b) cannot detect a large fraction of small bubbles (<3cm) and (c) is unable to track the azimuthal motion of bubbles in the larger bed. The scalability of the algorithm is discussed by comparing the computational cost of computing bubble statistics on highly resolved grids. Even though 3D bubble detection is significantly more expensive than 2D detection, the cost is still negligible compared to the cost of accurate simulations. Besides application to fluidization simulation data of large fluidized beds, this algorithm can be easily extended to characterize bubbles, droplets and clusters in other areas of multiphase flows.
Mechanisms of nutrient supply in oligotrophic ocean systems remain inadequately understood and quantified. In the North Atlantic Subtropical Gyre, for example, the observed rates of new production ...are apparently not balanced by nutrient supply via vertical mixing. Mesoscale eddies have been hypothesized as a mechanism for vertical nutrient pumping into the euphotic zone, but the full range and magnitude of biogeochemical impacts by eddies remain uncertain. We evaluated a cyclonic eddy located near Bermuda for its effect on water column biogeochemistry. In the density range σθ 26.1 to 26.7, an eddy core with anomalous salinity, temperature, and biogeochemical properties was observed, suggesting that the eddy was not formed with local water (i.e., not formed of the waters surrounding the eddy at the time of observations), hence complicating efforts to quantify biogeochemical processes in the eddy. We combined conservative hydrographic tracers (density versus potential temperature and salinity) and quasi‐conservative biogeochemical tracers (density versus NO, PO, and total organic carbon) to propose the origin of the eddy core water to have been several hundred kilometers to the southeast of the eddy location at sampling. By comparing the observed eddy core's biogeochemical properties with those near the proposed origin, we estimate the net changes in biogeochemical properties that occurred. A conservative estimate of export was 0.5 ± 0.34 mol N m−2 via sinking particles, with export occurring prior to our period of direct observation. Our results suggest that biogeochemical signals induced by mesoscale eddies could survive to be transported over long distances, thus providing a mechanism for lateral fluxes of nutrients and AOU (apparent oxygen utilization). Given that the proposed source area of this eddy is relatively broad, and the eddy‐mixing history before our sampling is unknown, uncertainty remains in our assessment of the true biogeochemical impact of mesoscale eddies in the gyre.
•Indicators of the effectiveness of climate change adaptation are urgently required.•Conceptual, analytical and practical challenges exist in doing so.•A flexible framework for climate change ...adaptation indicators is proposed.•Further work required to support indicator development is identified.
Impacts of climate change on natural and human systems will become increasingly severe as the magnitude of climate change increases. Climate change adaptation interventions to address current and projected impacts are thus paramount. Yet, evidence on their effectiveness remains limited, highlighting the need for appropriate ecological indicators to measure progress of climate change adaptation for the natural environment. We outline conceptual, analytical, and practical challenges in developing such indicators, before proposing a framework with three process-based and two results-based indicator types to track progress in adapting to climate change. We emphasize the importance of dynamic assessment and modification over time, as new adaptation targets are set and/or as intervention actions are monitored and evaluated. Our framework and proposed indicators are flexible and widely applicable across species, habitats, and monitoring programmes, and could be accommodated within existing national or international frameworks to enable the evaluation of both large-scale policy instruments and local management interventions. We conclude by suggesting further work required to develop these indicators fully, and hope this will stimulate the use of ecological indicators to evaluate the effectiveness of policy interventions for the adaptation of the natural environment across the globe.
Although thrombolytic therapy for acute myocardial infarction (MI) is recommended without regard for infarct location, treatment results are less impressive for inferior than for anterior MI because ...the amount of myocardium at risk is smaller and less strategically located, and the mortality risk is lower. Whereas the risks associated with anterior MI are relatively constant, high risk subsets of patients with an inferior MI can be identified by simple electrocardiographic criteria, including left precordial ST segment depression, complete atrioventricular heart block and right precordial ST segment elevation. Unfortunately, none of the placebo-controlled, randomized trials have analyzed the benefit of thrombolytic therapy for inferior MI in high risk versus low risk subsets.
Thrombolytic therapy should be more successful in reducing infarct size and decreasing mortality in high risk patients with an inferior MI. Thrombolytic therapy may not decrease hospital mortality in low risk patients (baseline risk 2% to 4%) or those with symptom duration >6 h. Whereas it is arguable whether coronary angioplasty is superior to thrombolytic therapy in anterior MI, there are no mortality data to support using angioplasty as a primary or rescue reperfusion strategy instead of thrombolytic therapy in inferior MI, unless thrombolytic contraindications are present or the patient is in cardiogenic shock.
Seagrass systems are integral components of both local and global carbon cycles and can substantially modify seawater biogeochemistry, which has ecological ramifications. However, the influence of ...seagrass on porewater biogeochemistry has not been fully described, and the exact role of this marine macrophyte and associated microbial communities in the modification of porewater chemistry remains equivocal. In the present study, carbonate chemistry in the water column and porewater was investigated over diel timescales in contrasting, tidally influenced seagrass systems in Southern California and Bermuda, including vegetated (
Zostera marina
) and unvegetated biomes (0–16 cm) in Mission Bay, San Diego, USA and a vegetated system (
Thallasia testudinium
) in Mangrove Bay, Ferry Reach, Bermuda. In Mission Bay, dissolved inorganic carbon (DIC) and total alkalinity (TA) exhibited strong increasing gradients with sediment depth. Vertical porewater profiles differed between the sites, with almost twice as high concentrations of DIC and TA observed in the vegetated compared to the unvegetated sediments. In Mangrove Bay, both the range and vertical profiles of porewater carbonate parameters such as DIC and TA were much lower and, in contrast to Mission Bay where no distinct temporal signal was observed, biogeochemical parameters followed the semi-diurnal tidal signal in the water column. The observed differences between the study sites most likely reflect a differential influence of biological (biomass, detritus and infauna) and physical processes (e.g., sediment permeability, residence time and mixing) on porewater carbonate chemistry in the different settings.
Objective: Despite strong evidence supporting the efficacy of family-based behavioral treatment (FBBT) for pediatric obesity, programs rarely achieve optimal effectiveness for all youth. ...Understanding treatment response among racially/ethnically diverse youth and the role of psychological concerns in obesity treatment response will better inform pediatric psychologists' treatment recommendations in pediatric obesity populations. The current study aimed to evaluate (a) FBBT effectiveness in a racially/ethnically diverse population and (b) the rates, and possible impact, of psychological comorbidities at baseline on treatment outcomes. Method: Participants included 351 youth who had obesity and their families who participated in 12 weeks of group FBBT. Parent-reported psychological concerns were measured at baseline using the Pediatric Symptom Checklist-17, and anthropometric data were collected at baseline and treatment end. Paired-samples t-tests and mixed-effects repeated-measures analysis of covariance were utilized to examine psychological predictors of changes in body mass index percent of the 95th percentile (%95thpercentile) during treatment. Results: No differences in FBBT response based on race or ethnicity were identified. Findings indicated that a higher baseline %95thpercentile was associated with more internalizing, externalizing, and total psychological concerns. While youth in the intervention experienced a significant reduction in %95thpercentile from baseline to treatment end overall, youth with elevated baseline externalizing concerns did not exhibit significant decreases in %95thpercentile. Conclusions: FBBT was demonstrated to be equally effective across racial/ethnic groups, while significant differences were observed based on psychological concerns reported at baseline. This study highlights the utility of preliminary psychological screening to promote individualized care within pediatric obesity treatment.
Implications for Impact Statement
This study evaluated family based behavioral treatment (FBBT) response in a racially/ethnically diverse population and explored the impact of child psychological concerns on FBBT response. Psychological screening prior to pediatric weight management interventions may help identify youth at risk for suboptimal benefit of FBBT. Treatment recommendations based on psychological screening results are discussed.
This paper describes the medical therapy used in the COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial and its effect on risk factors.
Most cardiovascular ...clinical trials test a single intervention. The COURAGE trial tested multiple lifestyle and pharmacologic interventions (optimal medical therapy) with or without percutaneous coronary intervention in patients with stable coronary disease.
All patients, regardless of treatment assignment, received equivalent lifestyle and pharmacologic interventions for secondary prevention. Most medications were provided at no cost. Therapy was administered by nurse case managers according to protocols designed to achieve predefined lifestyle and risk factor goals.
The patients (n = 2,287) were followed for 4.6 years. There were no significant differences between treatment groups in proportion of patients achieving therapeutic goals. The proportion of smokers decreased from 23% to 19% (p = 0.025), those who reported <7% of calories from saturated fat increased from 46% to 80% (p < 0.001), and those who walked >or=150 min/week increased from 58% to 66% (p < 0.001). Body mass index increased from 28.8 +/- 0.13 kg/m(2) to 29.3 +/- 0.23 kg/m(2) (p < 0.001). Appropriate medication use increased from pre-randomization to 5 years as follows: antiplatelets 87% to 96%; beta-blockers 69% to 85%; renin-angiotensin-aldosterone system inhibitors 46% to 72%; and statins 64% to 93%. Systolic blood pressure decreased from a median of 131 +/- 0.49 mm Hg to 123 +/- 0.88 mm Hg. Low-density lipoprotein cholesterol decreased from a median of 101 +/- 0.83 mg/dl to 72 +/- 0.88 mg/dl.
Secondary prevention was applied equally and intensively to both treatment groups in the COURAGE trial by nurse case managers with treatment protocols and resulted in significant improvement in risk factors. Optimal medical therapy in the COURAGE trial provides an effective model for secondary prevention among patients with chronic coronary disease. (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation; NCT00007657).
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