303 research outputs found
eBank UK: linking research data, scholarly communication and learning
This paper includes an overview of the changing landscape of scholarly communication and describes outcomes from the innovative eBank UK project, which seeks to build links from e-research through to e-learning. As introduction, the scholarly knowledge cycle is described and the role of digital repositories and aggregator services in linking data-sets from Grid-enabled projects to e-prints through to peer-reviewed articles as resources in portals and Learning Management Systems, are assessed. The development outcomes from the eBank UK project are presented including the distributed information architecture, requirements for common ontologies, data models, metadata schema, open linking technologies, provenance and workflows. Some emerging challenges for the future are presented in conclusion
Nonlinear Scattering of a Bose-Einstein Condensate on a Rectangular Barrier
We consider the nonlinear scattering and transmission of an atom laser, or
Bose-Einstein condensate (BEC) on a finite rectangular potential barrier. The
nonlinearity inherent in this problem leads to several new physical features
beyond the well-known picture from single-particle quantum mechanics. We find
numerical evidence for a denumerably infinite string of bifurcations in the
transmission resonances as a function of nonlinearity and chemical potential,
when the potential barrier is wide compared to the wavelength of oscillations
in the condensate. Near the bifurcations, we observe extended regions of
near-perfect resonance, in which the barrier is effectively invisible to the
BEC. Unlike in the linear case, it is mainly the barrier width, not the height,
that controls the transmission behavior. We show that the potential barrier can
be used to create and localize a dark soliton or dark soliton train from a
phonon-like standing wave.Comment: 15 pages, 15 figures, new version includes clarification of
definition of transmission coefficient in general nonlinear vs. linear cas
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Coronary Artery Calcification (CAC) and Post-Trial Cardiovascular Events and Mortality Within the Women's Health Initiative (WHI) Estrogen-Alone Trial.
BackgroundAmong women aged 50 to 59 years at baseline in the Women's Health Initiative (WHI) Estrogen-Alone (E-Alone) trial, randomization to conjugated equine estrogen-alone versus placebo was associated with lower risk of myocardial infarction and mortality, and, in an ancillary study, the WHI-CACS (WHI Coronary Artery Calcification Study) with lower CAC, measured by cardiac computed tomography ≈8.7 years after baseline randomization. We hypothesized that higher CAC would be related to post-trial coronary heart disease (CHD), cardiovascular disease (CVD), and total mortality, independent of baseline randomization or risk factors.Methods and resultsWHI-CACS participants (n=1020) were followed ≈8 years from computed tomography scan in 2005 (mean age=64.4) through 2013 for incident CHD (myocardial infarction and fatal CHD, n=17), CVD (n=69), and total mortality (n=55). Incident CHD and CVD analyses excluded women with CVD before scan (n=89). Women with CAC=0 (n=54%) had very low age-adjusted rates/1000 person-years of CHD (0.91), CVD (5.56), and mortality (3.45). In comparison, rates were ≈2-fold higher for women with any CAC (>0). Associations were not modified by baseline randomization to conjugated equine estrogen-alone versus placebo. Adjusted for baseline randomization and risk factors, the hazard ratio (95% confidence interval) for CAC >100 (19%) was 4.06 (2.11, 7.80) for CVD and 2.70 (1.26, 5.79) for mortality.ConclusionsAmong a subset of postmenopausal women aged 50 to 59 years at baseline in the WHI E-Alone Trial, CAC at mean age of 64 years was strongly related to incident CHD, CVD, and to total mortality over ≈8 years, independent of baseline randomization to conjugated equine estrogen-alone versus placebo or CVD risk factors.Clinical trial registrationURL: https://www.clinicaltrials.gov. Unique identifier: NCT00000611
Circulating Leptin and Branched Chain Amino Acids – Correlation with Intraductal Papillary Mucinous Neoplasm Dysplastic Grade
Background: The most common type of mucinous pancreatic cyst that may progress to pancreatic cancer is intraductal papillary mucinous neoplasm (IPMN). Low-risk IPMN with low-/moderate-grade dysplasia may be safely watched, whereas high-risk IPMN with high-grade dysplasia or invasive components should undergo resection. However, there is currently no reliable means of making this distinction. We hypothesize that blood concentrations of insulin resistance biomarkers may aid in the differentiation of low- and high-risk IPMN.
Methods: Plasma/serum was collected from consented patients undergoing pancreatic resection. IPMN diagnosis and dysplastic grade were confirmed by surgical pathology. The study included 235 IPMN (166 low/moderate grade, 39 high grade, 30 invasive). Circulating levels of leptin, branched chain amino acids (BCAA), and retinol-binding protein-4 (RBP-4) were measured by enzyme-linked immunoassay and correlated with surgical pathology.
Results: Circulating leptin levels (mean ± SE) were significantly higher in patients with low/moderate IPMN than in high-grade/invasive IPMN (15,803 ± 1686 vs. 10,275 ± 1228 pg/ml; p = 0.0086). Leptin levels were positively correlated with BMI (r = 0.65, p < 0.0001) and were higher in females (p < 0.0001). Stratified analysis showed that mean leptin levels were significantly different between low/moderate and high/invasive IPMNs only in females (24,383 ± 2748 vs. 16,295 ± 2040 pg/ml; p = 0.020). Conversely, circulating BCAA levels were lower in low/moderate IPMN than in high-grade/invasive IPMN (0.38 ± 0.007 vs. 0.42 ± 0.01 mM; p = 0.011). No significant differences in RBP-4 levels were observed.
Conclusions: Circulating leptin in females and BCAA correlates with IPMN dysplastic grade and, if combined with clinical characteristics, have the potential to improve clinical decision-making
Txikispora philomaios n. sp., n. g., a micro-eukaryotic pathogen of amphipods, reveals parasitism and hidden diversity in Class Filasterea
This study provides a morphological, ultrastructural, and phylogenetic characterization of a novel micro-eukaryotic parasite (2.3–2.6 µm) infecting amphipod genera Echinogammarus and Orchestia. Longitudinal studies across two years revealed that infection prevalence peaked in late April and May, reaching 64% in Echinogammarus sp. and 15% in Orchestia sp., but was seldom detected during the rest of the year. The parasite infected predominantly hemolymph, connective tissue, tegument, and gonad, although hepatopancreas and nervous tissue were affected in heavier infections, eliciting melanization and granuloma formation. Cell division occurred inside walled parasitic cysts, often within host hemocytes, resulting in hemolymph congestion. Small subunit (18S) rRNA gene phylogenies including related environmental sequences placed the novel parasite as a highly divergent lineage within Class Filasterea, which together with Choanoflagellatea represent the closest protistan relatives of Metazoa. We describe the new parasite as Txikispora philomaios n. sp. n. g., the first confirmed parasitic filasterean lineage, which otherwise comprises four free-living flagellates and a rarely observed endosymbiont of snails. Lineage-specific PCR probing of other hosts and surrounding environments only detected T. philomaios in the platyhelminth Procerodes sp. We expand the known diversity of Filasterea by targeted searches of metagenomic datasets, resulting in 13 previously unknown lineages from environmental samples.Ministerio de Economía y Competitividad, Grant/Award Number: BFU2017- 90114- P; Horizon 2020 Framework Programme, Grant/Award Number: 747789; Department for Environment, Food and Rural Affairs, UK Government, Grant/Award Number: FB002A and FC1214; Hezkuntza, Hizkuntza Politika Eta Kultura Saila, Eusko Jaurlaritza, Grant/Award Number: PRE_2016_2_0124; Agencia Estatal de Investigación (AEI); Fondo Europeo de Desarrollo Regional (FEDER); Ayuda Juan de la Cierva—Incorporación, Grant/Award Number: IJC2018- 036657-
Climate vulnerability assessment for Pacific salmon and steelhead in the California Current Large Marine Ecosystem.
Major ecological realignments are already occurring in response to climate change. To be successful, conservation strategies now need to account for geographical patterns in traits sensitive to climate change, as well as climate threats to species-level diversity. As part of an effort to provide such information, we conducted a climate vulnerability assessment that included all anadromous Pacific salmon and steelhead (Oncorhynchus spp.) population units listed under the U.S. Endangered Species Act. Using an expert-based scoring system, we ranked 20 attributes for the 28 listed units and 5 additional units. Attributes captured biological sensitivity, or the strength of linkages between each listing unit and the present climate; climate exposure, or the magnitude of projected change in local environmental conditions; and adaptive capacity, or the ability to modify phenotypes to cope with new climatic conditions. Each listing unit was then assigned one of four vulnerability categories. Units ranked most vulnerable overall were Chinook (O. tshawytscha) in the California Central Valley, coho (O. kisutch) in California and southern Oregon, sockeye (O. nerka) in the Snake River Basin, and spring-run Chinook in the interior Columbia and Willamette River Basins. We identified units with similar vulnerability profiles using a hierarchical cluster analysis. Life history characteristics, especially freshwater and estuary residence times, interplayed with gradations in exposure from south to north and from coastal to interior regions to generate landscape-level patterns within each species. Nearly all listing units faced high exposures to projected increases in stream temperature, sea surface temperature, and ocean acidification, but other aspects of exposure peaked in particular regions. Anthropogenic factors, especially migration barriers, habitat degradation, and hatchery influence, have reduced the adaptive capacity of most steelhead and salmon populations. Enhancing adaptive capacity is essential to mitigate for the increasing threat of climate change. Collectively, these results provide a framework to support recovery planning that considers climate impacts on the majority of West Coast anadromous salmonids
Postnatal ExErcise Partners Study (PEEPS): A Pilot Randomised Trial of a Dyadic Physical Activity Intervention for Postpartum Mothers and a Significant Other
Research suggests dyadic interventions can increase physical activity; such interventions are untested within postpartum parent couples. A three-armed pilot randomised trial addressed this gap and tested which type of dyadic intervention is most effective. Inactive postpartum mothers and a significant other were recruited in Australia (n = 143 assessed for eligibility) and randomised in a single-blinded fashion (i.e., participants were blinded) to 1 of 3 dyadic conditions involving a single face-to-face session with access to web-based group support: a minimal treatment control (n = 34), collaborative planning group (n = 38), or collaborative planning + need supportive communication group (n = 30). Participants were asked to wear their accelerometers for 8 days and completed self-report measures at baseline, end of intervention (week 4), and follow-up (week 12). We expected dyads in the collaborative planning + need supportive communication group would have the greatest increases in Physical Activity (PA), autonomous motivation, and partners’ need supportive behaviours; and decreases in controlled motivation and controlling partner behaviours. Results from 51 dyads using Bayesian actor-partner interdependence models provided some evidence for a small positive effect on total physical activity at follow-up for postpartum mothers in the collaborative planning group and for partners in the collaborative planning + need supportive communication group. Furthermore, partners in the collaborative planning + need supportive communication group were more likely to engage in some vigorous PA. At follow-up, postpartum mothers in the collaborative planning + need supportive communication group scored lower on personal autonomous reasons. The impact of prior specification mean intervention effects need to be interpreted with caution. Progression to a full trial is warranted. Keywords: Postpartum, Mothers, Dyads, Randomized controlled trial, Physical activity. This project was funded by a Curtin International Postgraduate Research Scholarship/ Health Sciences Faculty International Research Scholarship. Andreas Stenling was supported by an international postdoc grant from the Swedish Research Council (dnr: 2017-00273)
Coronary Artery Calcification (CAC) and Post-Trial Cardiovascular Events and Mortality Within the Women\u27s Health Initiative (WHI) Estrogen-Alone Trial
BACKGROUND: Among women aged 50 to 59 years at baseline in the Women\u27s Health Initiative (WHI) Estrogen-Alone (E-Alone) trial, randomization to conjugated equine estrogen-alone versus placebo was associated with lower risk of myocardial infarction and mortality, and, in an ancillary study, the WHI-CACS (WHI Coronary Artery Calcification Study) with lower CAC, measured by cardiac computed tomography approximately 8.7 years after baseline randomization. We hypothesized that higher CAC would be related to post-trial coronary heart disease (CHD), cardiovascular disease (CVD), and total mortality, independent of baseline randomization or risk factors.
METHODS AND RESULTS: WHI-CACS participants (n=1020) were followed approximately 8 years from computed tomography scan in 2005 (mean age=64.4) through 2013 for incident CHD (myocardial infarction and fatal CHD, n=17), CVD (n=69), and total mortality (n=55). Incident CHD and CVD analyses excluded women with CVD before scan (n=89). Women with CAC=0 (n=54%) had very low age-adjusted rates/1000 person-years of CHD (0.91), CVD (5.56), and mortality (3.45). In comparison, rates were approximately 2-fold higher for women with any CAC ( \u3e 0). Associations were not modified by baseline randomization to conjugated equine estrogen-alone versus placebo. Adjusted for baseline randomization and risk factors, the hazard ratio (95% confidence interval) for CAC \u3e 100 (19%) was 4.06 (2.11, 7.80) for CVD and 2.70 (1.26, 5.79) for mortality.
CONCLUSIONS: Among a subset of postmenopausal women aged 50 to 59 years at baseline in the WHI E-Alone Trial, CAC at mean age of 64 years was strongly related to incident CHD, CVD, and to total mortality over approximately 8 years, independent of baseline randomization to conjugated equine estrogen-alone versus placebo or CVD risk factors.
CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00000611
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