44 research outputs found

    Processed data from Particle Imaging Velocimetry (PIV) observations of Tritia trivittata and Tritia obsoleta behavior in various flow tanks

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    Dataset: Snail larvae in turbulence and wavesDispersing marine larvae can alter their physical transport by swimming vertically or sinking in response to environmental signals. However, it remains unknown whether any signals could enable larvae to navigate over large scales. We tested whether flow-induced larval behaviors vary with adults' physical environments using congeneric snail larvae from the wavy continental shelf (Tritia trivittata) and from turbulent inlets (Tritia obsoleta). This dataset includes observations of larvae in turbulence, in rotating flows dominated by vorticity or strain rates, and in rectilinear wave oscillations. Larval and water motion were observed using near-infrared particle image velocimetry (IR PIV), and analyses identified threshold signals causing larvae to change their direction or magnitude of propulsive force. The two species reacted similarly to turbulence but differently to waves, and their transport patterns would diverge in wavy, offshore regions. Wave-induced behaviors provide evidence that larvae may detect waves as both motions and sounds useful in navigation. For a complete list of measurements, refer to the supplemental document 'Field_names.pdf', and a full dataset description is included in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: http://www.bco-dmo.org/dataset/739790NSF Division of Ocean Sciences (NSF OCE) OCE-106062

    A Study on Bulk and Skin Temperature Difference using Observations from Atlantic and Pacific Coastal Regions of United States

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    The article of record as published may be found at  http://dx.doi.org/10.1117/12.2263533Analysis of bulk-skin sea surface temperature (SST) difference form the west and east coasts of United States is presented using the data collected from three field experiments. These experiments were conducted at offshore Duck, North Carolina and in the Monterey Bay of the California coastal region. Bulk SST measurements were made using conventional thermistors from a depth of one meter below the sea level. Infrared radiometers were used to measure the surface skin SST. Depending on measurement depth and prevailing conditions, the bulk SST can differ from skin SST by few tenths of a degree to O(1°C). Difference between bulk and skin SST arise from cools skin and warm layer effects. Bulk-skin SST difference (ΔSST) estimated from east coast observations varied from -0.46°C to 1.24°C. Here, the bulk SST was higher than skin SST most of the time during the observations. This indicates cool skin effect was the dominant factor determining the ΔSST in the east coast. For wind speeds less than 4 m s-1, we also noticed an increase in ΔSST. Additionally, for low winds (< 4 m s-1) ΔSST also varied diurnally with the occurrence of generally higher ΔSST in the nighttime in comparison with daytime. Moreover, increase in downwelling longwave radiation reduced the bulk-skin SST difference. ΔSST calculated from the observation in the Monterey bay varied between ~2.3° and ~-2.3°C. This was higher than the variability ΔSST observed at the east coast. Moreover, ΔSST variability observed at west coast was independent of wind speed.CASPER is funded by the Office of Naval Research (ONR) under its Multidisciplinary University Research Initiative (MURI) program, grant N0001416WX00469, under project managers Dr. Daniel Eleuterio and Steve Russell

    Warm Layer and Cool Skin Corrections for Bulk Water Temperature Measurements for Air-Sea Interaction Studies

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    Data used for this study are available at https://workspace.axiomdatascience.com/group/282520/projects.The article of record as published may be found at http://dx.doi.org/10.1002/2017JC012688The sea surface temperature (SST) relevant to air-sea interaction studies is the temperature immediately adjacent to the air, referred to as skin SST. Generally, SST measurements from ships and buoys are taken at depths varies from several centimeters to five meters below the surface. These measurements, known as bulk SST, can differ from skin SST up to O(1°C). Shipboard bulk and skin SST measurements were made during the Coupled Air- Sea Processes and Electromagnetic ducting Research east coast field campaign (CASPER-East). An Infrared SST Autonomous Radiometer (ISAR) recorded skin SST, while R/V Sharp’s Surface Mapping System (SMS) provided bulk SST from one-meter water depth. Since the ISAR is sensitive to sea spray and rain, missing skin SST data occurred in these conditions. However, SMS measurement is less affected by adverse weather and provided continuous bulk SST measurements. It is desirable to correct the bulk SST to obtain a good representation of the skin SST, which is the objective of this research.Bulk-skin SST difference has been examined with respect to meteorological factors associated with cool skin and diurnal warm layers. Strong influences of wind speed, diurnal effects and net longwave radiation flux on temperature difference are noticed. A three-step scheme is established to correct for wind effect, diurnal variability and then for dependency on net longwave radiation flux. Scheme is tested and compared to existing correction schemes. This method is able to effectively compensate for multiple factors acting to modify bulk SST measurements over the range of conditions experienced during CASPER-East

    Stimulation of adipogenesis of adult adipose-derived stem cells using substrates that mimic the stiffness of adipose tissue.

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    Biochemical and biomechanical extracellular matrix (ECM) cues have recently been shown to play a role in stimulating stem cell differentiation towards several lineages, though how they combine to induce adipogenesis has been less well studied. The objective of this study was to recapitulate both the ECM composition and mechanical properties of adipose tissue in&nbsp;vitro to stimulate adipogenesis of human adipose-derived stem cells (ASCs) in the absence of exogenous adipogenic growth factors and small molecules. Adipose specific ECM biochemical cues have been previously shown to influence adipogenic differentiation; however, the ability of biomechanical cues to promote adipogenesis has been less defined. Decellularized human lipoaspirate was used to functionalize polyacrylamide gels of varying stiffness to allow the cells to interact with adipose-specific ECM components. Culturing ASCs on gels that mimicked the native stiffness of adipose tissue (2&nbsp;kPa) significantly upregulated adipogenic markers, in the absence of exogenous adipogenic growth factors and small molecules. As substrate stiffness increased, the cells became more spread, lost their rounded morphology, and failed to upregulate adipogenic markers. Together these data imply that as with other lineages, mechanical cues are capable of regulating adipogenesis in ASCs

    Data from: Turbulence induces metabolically costly behaviors and inhibits food capture in oyster larvae, causing net energy loss

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    Planktotrophic invertebrate larvae require energy to develop, disperse, and settle successfully, and it is unknown how their energetics is impacted by turbulence. Ciliated larvae gain metabolic energy from their phytoplankton food to offset the energetic costs of growth, development, and ciliary activity for swimming and feeding. Turbulence may affect the energetic balance by inducing behaviors that alter the metabolic costs and efficiency of swimming, by raising the encounter rate with food particles, and by inhibiting food capture. We used experiments and an empirical model to quantify the net rate of energy gain, swimming efficiency, and food capture efficiency for eyed oyster larvae (Crassostrea virginica) in turbulence. At dissipation rates representative of coastal waters, larvae lost energy even when food concentrations were very high. Both feeding activity and turbulence-induced behaviors incurred high metabolic costs. Swimming efficiency was concave up versus dissipation rate, suggesting that ciliary activity for food handling became more costly while swimming became more efficient with turbulence intensity. Though counter-intuitive, swimming may have become more efficient in turbulence because vorticity-induced rotation caused larvae to swim more horizontally, which requires less effort than swimming vertically against the pull of gravity. Overall, however, larvae failed to offset high activity costs with food energy gains because turbulence reduced food capture efficiency more than it enhanced food encounter rates. Younger, smaller larvae may have some energetic advantages, but competent larvae would lose energy at turbulence intensities they experience frequently, suggesting that turbulence-induced starvation may account for much of oysters' high larval mortality

    A study on bulk and skin temperature difference using observations from Atlantic and Pacific Coastal regions of United States

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    The article of record as published may be found at  http://dx.doi.org/10.1117/12.2263533Analysis of bulk-skin sea surface temperature (SST) difference form the west and east coasts of United States is presented using the data collected from three field experiments. These experiments were conducted at offshore Duck, North Carolina and in the Monterey Bay of the California coastal region. Bulk SST measurements were made using conventional thermistors from a depth of one meter below the sea level. Infrared radiometers were used to measure the surface skin SST. Depending on measurement depth and prevailing conditions, the bulk SST can differ from skin SST by few tenths of a degree to O(1°C). Difference between bulk and skin SST arise from cools skin and warm layer effects. Bulk-skin SST difference (ΔSST) estimated from east coast observations varied from -0.46°C to 1.24°C. Here, the bulk SST was higher than skin SST most of the time during the observations. This indicates cool skin effect was the dominant factor determining the ΔSST in the east coast. For wind speeds less than 4 m s-1, we also noticed an increase in ΔSST. Additionally, for low winds (< 4 m s-1) ΔSST also varied diurnally with the occurrence of generally higher ΔSST in the nighttime in comparison with daytime. Moreover, increase in downwelling longwave radiation reduced the bulk-skin SST difference. ΔSST calculated from the observation in the Monterey bay varied between ~2.3° and ~-2.3°C. This was higher than the variability ΔSST observed at the east coast. Moreover, ΔSST variability observed at west coast was independent of wind speed.CASPER is funded by the Office of Naval Research (ONR) under its Multidisciplinary University Research Initiative (MURI) program, grant N0001416WX00469, under project managers Dr. Daniel Eleuterio and Steve Russell

    behavior_data

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    "behavior_data.dat" is a comma-separated file containing behavior data from PIV measurements

    Summary_Data

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    "Summary_Data.csv" is a comma-separated (.csv) file summarizing population-average (flask-level) measurements
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