Hannah L. Stewart

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This study documents the changes in nutrient fluxes associated with internal tidal bores arriving on Florida Keys coral reefs and points to biological use of subthermocline nitrate brought onshore by this mechanism. Internal bores on Conch Reef, Florida Keys, are associated with concentrations of 1.0–4.0 ␮mol L Ϫ1 nitrate (NO) and 0.1–0.3 Ϫ 3 ␮mol L Ϫ1(More)
To determine the relative importance of different sources of nitrate to the annual nitrogen needs of the giant kelp Macrocystis pyrifera, we measured ambient nitrate concentrations at a kelp forest for 13 months and characterized nitrate delivery using water column thermal structure and flow data collected in the forest and at its offshore edge. The(More)
This work was motivated by subtidal observations of red urchins (Strongylocentrotus franciscanus) moving their spines into streamlined positions as water current increased in the field. Trials in a flume across flow speeds from 0 to 65 cm s(-1) enabled us to observe the change in overall shape of the urchins and quantify the decrease in spine angle that(More)
Neurobiological models of obesity postulate that obese individuals have difficulty regulating food intake partly because they attribute excessive salience to stimuli signaling food availability. Typically, human studies that investigate the relationship between brain responses to food-related stimuli and obesity present food cues without subsequent delivery(More)
Like many reefs worldwide, reefs in French Polynesia are experiencing a shift from coral-dominated to algal-dominated systems. The macroalga Turbinaria ornata comprises the majority of the increasing algal biomass on the barrier reefs surrounding these islands, and its distribution is increasing throughout this region. Aspects of the ecomorphology of(More)
Although normative studies have traditionally found that blood pressure (BP) fluctuations are asymptomatic, recent research by Pennebaker et al. [(1982). Psychophysiology 19: 201-210] has suggested that systolic blood pressure (SBP) changes are, in fact, highly correlated with idiosyncratic patterns of symptoms within individuals. The present study was(More)
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