9,625 research outputs found

    Remote sensing observations of ocean physical and biological properties in the region of the Southern Ocean Iron Experiment (SOFeX)

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    Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 111 (2006): C06026, doi:10.1029/2005JC003289.Satellite remote sensing estimates of surface chlorophyll, temperature, wind speed, and sea ice cover are examined in the region of the Southern Ocean Iron Experiment (SOFeX). Our objectives are to place SOFeX into a regional context and highlight regional mesoscale spatial and monthly temporal variability. SOFeX fertilized two patches with iron, one south of the Antarctic Polar front (PF) and one north of the PF but south of the Subantarctic Front (SAF). Satellite observable phytoplankton blooms developed in both patches. The spring sea-ice retreat near the south patch site was delayed in the 2001-2002 season, in turn delaying the naturally occurring, modest spring bloom in this region. Ambient surface chlorophyll concentrations for the area surrounding the southern patch during January 2002 are low (mean 0.26 mg/m3) compared with climatological January values (0.42 mg/m3). Regions east and west at similar latitudes exhibited higher mean chlorophyll concentrations (0.79 and 0.74 mg/m3, respectively). These modest phytoplankton blooms were likely stimulated by melting sea-ice via changes in the light-mixing regime and release of iron, and were smaller in magnitude than the iron-induced bloom within the SOFeX southern patch (> 3 mg/m3). Iron inputs from melting ice may drive much of the natural spatial and temporal variability within the seasonal ice zone. Mean chlorophyll concentrations surrounding the SOFeX northern patch site were similar to climatological values during the SOFeX season. The northern patch was stretched into a long, thin filament along the southern boundary of the SAF, likely increasing the mixing/dilution rate with surrounding waters.S. Doney and K. Moore were supported by NASA grant NAG5-12520 from the NASA Ocean Biogeochemistry Program

    A practice-led approach to facial animation research

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    In facial expression research, it is well established that certain emotional expressions are universally recognized. Studies into the observer perception of dynamic expressions have built upon this research by highlighting the importance of particular facial regions, timings, and temporal configurations to perception and interpretation. In many studies, the stimuli for such studies have been generated through posing by non-experts or performances by trained actors. However, skilled character animators are capable of crafting recognizable, believable emotional facial expressions as a part of their professional practice. ‘Emotional Avatars’ was conceived as an interdisciplinary research project which would draw upon the knowledge of animation practice and emotional psychology. The aim of the project was to jointly investigate the artistic generation and observer perception of emotional expression animation to determine whether the nuances of emotional facial expression could be artistically choreographed to enhance audience interpretation

    Social support moderates D-dimer and self-rated successful aging within people with HIV and older adults.

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    Many factors can influence perceptions of successful aging (SA), including social isolation and poor physical health. We hypothesized that social support attenuates the negative effect of plasma D-dimer, a correlate of HIV and aging, on SA. Participants included 230 adults (134 people with HIV; PWH, 96 HIV-), ages 36-65, segregated into age cohorts with up to 5 yearly visits. Multilevel modeling examined longitudinal within-person associations between D-dimer, social support, and SA. Social support moderated the relationship between D-dimer and SA and was significant among PWH and older individuals (ages 56-65), but not HIV- or younger cohorts. This association was significant only at extreme levels of social support, with significant decreases in social support potentiating the negative impact of D-dimer on SA and significant increases in social support facilitating increased SA. Despite declining health, high social support may improve SA in PWH and older adults, and low support may be especially problematic for older adults

    Fabrication of Micropatterned Hydrogels for Neural Culture Systems using Dynamic Mask Projection Photolithography

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    Increasingly, patterned cell culture environments are becoming a relevant technique to study cellular characteristics, and many researchers believe in the need for 3D environments to represent in vitro experiments which better mimic in vivo qualities 1-3. Studies in fields such as cancer research 4, neural engineering 5, cardiac physiology 6, and cell-matrix interaction7,8have shown cell behavior differs substantially between traditional monolayer cultures and 3D constructs

    Quantum and classical chaos for a single trapped ion

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    In this paper we investigate the quantum and classical dynamics of a single trapped ion subject to nonlinear kicks derived from a periodic sequence of Guassian laser pulses. We show that the classical system exhibits diffusive growth in the energy, or 'heating', while quantum mechanics suppresses this heating. This system may be realized in current single trapped-ion experiments with the addition of near-field optics to introduce tightly focussed laser pulses into the trap.Comment: 8 pages, REVTEX, 8 figure

    Report of a workshop on large whale medical intervention : indications and technology development

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    Sponsors: Woods Hole Oceanographic Institution, Center for Coastal Studies, New England Aquarium. Location: Carriage House, Woods Hole Oceanographic Institution, Woods Hole MA 02543. Date: Monday February 7th 2000This one day interdisciplinary workshop, attended by 12 veterinarians 11 whale biologists, an engineer and the NMFS Regional Stranding Coordinator, was convened by Michael Moore, with financial support from the Woods Hole Oceanographic Institution Cecil and Ida Green Technology Innovation Fund. The goal was to examine ways in which veterinary medical techniques could assist in efforts to mitigate right whale mortality. In particular the indications and technology for the use of sedation during disentanglement efforts and antibiotic therapy for wounds after disentanglement were considered.Woods Hole Oceanographic Institution Cecil and Ida Green Technology Innovation Fun

    Lepidopteran Granivory Reduces Seed Counts in a Rare Species of Riparian Scour Prairies

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    In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Pennsylvania Baptisia australis var. australis is restricted to is also in decline and considered vulnerable. Because of these conservation concerns, insights into the natural history of the taxon in the state is valuable and will inform conservation efforts. Field surveys and fruit collections along the Allegheny River and herbarium collections were used to investigate and document granivory in Pennsylvania Baptisia australis var. australis, a phenomenon recorded in other parts of the species\u27 range, but not previously reported on in Pennsylvania. Using a model of best fit, the number of seeds found in fruit was found to be significantly impacted by the presence of granivores. We also report that visual surveys of fruits in the field are found to be accurate assessments of the presence and potential impact of granivores. In turn, our results will inform the conservation and management of Baptisia australis var. australis populations in Pennsylvania and highlight the importance of field surveys in protecting threatened taxa

    Quantitative Trait Locus Mapping of Winter Hardiness Metabolites in Autotetraploid Alfalfa (M. sativa)

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    In winter hardy alfalfa cultivars, cold acclimation occurs prior to the onset of freezing temperatures and normally is accompanied with a series of metabolic and morphological adjustments. We are studying the accumulation pattern of metabolites throughout the autumn previous to freezing and relating them to winter survival in an Fl segregating population between the cross of M. sativa subsp. sativa and subsp. falcata. Morphological components and soluble carbohydrates, protein, amino-N groups, and free fatty acids were measured in 2001 and 2002 in the field. Broad sense heritability was intermediate for shoot and root mass and height, and for metabolites, ranged from low (TNC=0.04) to high (starch=0.80). The genetic correlation between winter injury was not significant for most of the metabolites, except for soluble protein and amino-N group concentrations. The presence of allele al of MSAIC B, a cold-related gene, was positively associated with autumn plant height but negatively associated with root mass in the WISFAL-6 parent. Numerous QTL were detected for concentrations of metabolites. Our results suggest that winter injury and autumn biomass are controlled by different loci in this population
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