922 resultados para An eddy-resolving ocean model simulation
An exploratory non-LTE model atmosphere analysis of B-type supergiants in the Small Magellanic Cloud
Resumo:
A preliminary differential non-LTE model atmosphere analysis of moderate resolution (R ~ 5 000) and signal-to-noise ratio spectra of 48 Small Magellanic Cloud B-type supergiants is presented. Standard techniques are adopted, viz. plane-parallel geometry and radiative and hydrostatic equilibrium. Spectroscopic atmospheric parameters (T_eff, log g and v_turb), luminosities and chemical abundances (He, C, N, O, Mg and Si) are estimated. These are compared with those deduced for a comparable sample of Galactic supergiants. The SMC targets appear to have similar atmospheric parameters, luminosities and helium abundances to the Galactic sample. Their magnesium and silicon underabundances are compatible with those found for main sequence SMC objects and there is no evidence for any large variation in their oxygen abundances. By contrast both their carbon and nitrogen lines strengths are inconsistent with single abundances, while their nitrogen to carbon abundance ratios appear to vary by at least as much and probably more than that found in the Galactic sample.
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This paper introduces the application of linear multivariate statistical techniques, including partial least squares (PLS), canonical correlation analysis (CCA) and reduced rank regression (RRR), into the area of Systems Biology. This new approach aims to extract the important proteins embedded in complex signal transduction pathway models.The analysis is performed on a model of intracellular signalling along the janus-associated kinases/signal transducers and transcription factors (JAK/STAT) and mitogen activated protein kinases (MAPK) signal transduction pathways in interleukin-6 (IL6) stimulated hepatocytes, which produce signal transducer and activator of transcription factor 3 (STAT3).A region of redundancy within the MAPK pathway that does not affect the STAT3 transcription was identified using CCA. This is the core finding of this analysis and cannot be obtained by inspecting the model by eye. In addition, RRR was found to isolate terms that do not significantly contribute to changes in protein concentrations, while the application of PLS does not provide such a detailed picture by virtue of its construction.This analysis has a similar objective to conventional model reduction techniques with the advantage of maintaining the meaning of the states prior to and after the reduction process. A significant model reduction is performed, with a marginal loss in accuracy, offering a more concise model while maintaining the main influencing factors on the STAT3 transcription.The findings offer a deeper understanding of the reaction terms involved, confirm the relevance of several proteins to the production of Acute Phase Proteins and complement existing findings regarding cross-talk between the two signalling pathways.
Resumo:
OBJECTIVES: To evaluate the cost-effectiveness of an adapted U.S. model of pharmaceutical care to improve psychoactive prescribing for nursing home residents in Northern Ireland (Fleetwood NI Study).
DESIGN: Economic evaluation alongside a cluster randomized controlled trial.
SETTING: Nursing homes in NI randomized to intervention (receipt of the adapted model of care; n511) or control (usual care continued; n511).
PARTICIPANTS: Residents aged 65 and older who provided informed consent (N5253; 128 intervention, 125 control) and who had full resource use data at 12 months.
INTERVENTION: Trained pharmacists reviewed intervention home residents’ clinical and prescribing information for 12 months, applied an algorithm that guided them in assessing the appropriateness of psychoactive medication, and worked with prescribers (general practitioners) to make changes. The control homes received usual care in which there was no pharmacist intervention.
MEASUREMENTS: The proportion of residents prescribed one or more inappropriate psychoactive medications (according to standardized protocols), costs, and a cost-effectiveness acceptability curve. The latter two outcomes are the focus for this article.
RESULTS: The proportions of residents receiving inappropriate psychoactive medication at 12 months in the intervention and control group were 19.5% and 50.4%, respectively. The mean cost of healthcare resources used per resident per year was $4,923 (95% con?dence interval.
Resumo:
OBJECTIVES: To test the effect of an adapted U.S. model of pharmaceutical care on prescribing of inappropriate psychoactive (anxiolytic, hypnotic, and antipsychotic) medications and falls in nursing homes for older people in Northern Ireland (NI).
DESIGN: Cluster randomized controlled trial.
SETTING: Nursing homes randomized to intervention (receipt of the adapted model of care; n=11) or control (usual care continued; n=11).
PARTICIPANTS: Residents aged 65 and older who provided informed consent (N=334; 173 intervention, 161 control).
INTERVENTION: Specially trained pharmacists visited intervention homes monthly for 12 months and reviewed residents' clinical and prescribing information, applied an algorithm that guided them in assessing the appropriateness of psychoactive medication, and worked with prescribers (general practitioners) to improve the prescribing of these drugs. The control homes received usual care.
MEASUREMENTS: The primary end point was the proportion of residents prescribed one or more inappropriate psychoactive medicine according to standardized protocols; falls were evaluated using routinely collected falls data mandated by the regulatory body for nursing homes in NI.
RESULTS: The proportion of residents taking inappropriate psychoactive medications at 12 months in the intervention homes (25/128, 19.5%) was much lower than in the control homes (62/124, 50.0%) (odds ratio=0.26, 95% confidence interval=0.14–0.49) after adjustment for clustering within homes. No differences were observed at 12 months in the falls rate between the intervention and control groups.
CONCLUSION: Marked reductions in inappropriate psychoactive medication prescribing in residents resulted from pharmacist review of targeted medications, but there was no effect on falls.
Resumo:
We study an energy-constrained sandpile model with random neighbors. The critical behavior of the model is in the same universality class as the mean-field self-organized criticality sandpile. The critical energy E-c depends on the number of neighbors n for each site, but the various exponents are independent of n. A self-similar structure with n-1 major peaks is developed for the energy distribution p(E) when the system approaches its stationary state. The avalanche dynamics contributes to the major peaks appearing at E-Pk = 2k/(2n - 1) with k = 1,2,...,n-1, while the fine self-similar structure is a natural result of the way the system is disturbed. [S1063-651X(99)10307-6].
Resumo:
Turbulence characteristics in the Indonesian seas on the horizontal scale of order of 100 km were calculated with a regional model of the Indonesian seas circulation in the area based on the Princeton Ocean Model (POM). As is well known, the POM incorporates the Mellor–Yamada turbulence closure scheme. The calculated characteristics are: twice the turbulence kinetic energy per unit mass, <i>q</i><sup>2</sup>; the turbulence master scale, ℓ; mixing coefficients of momentum, <i>K</i><sub>M</sub>; and temperature and salinity, <i>K</i><sub>H</sub>; etc. The analyzed turbulence has been generated essentially by the shear of large-scale ocean currents and by the large-scale wind turbulence. We focused on the analysis of turbulence around important topographic features, such as the Lifamatola Sill, the North Sangihe Ridge, the Dewakang Sill, and the North and South Halmahera Sea Sills. In general, the structure of turbulence characteristics in these regions turned out to be similar. For this reason, we have carried out a detailed analysis of the Lifamatola Sill region because dynamically this region is very important and some estimates of mixing coefficients in this area are available. <br><br> Briefly, the main results are as follows. The distribution of <i>q</i><sup>2</sup> is quite adequately reproduced by the model. To the north of the Lifamatola Sill (in the Maluku Sea) and to the south of the Sill (in the Seram Sea), large values of <i>q</i><sup>2</sup> occur in the deep layer extending several hundred meters above the bottom. The observed increase of <i>q</i><sup>2</sup> near the very bottom is probably due to the increase of velocity shear and the corresponding shear production of <i>q</i><sup>2</sup> very close to the bottom. The turbulence master scale, ℓ, was found to be constant in the main depth of the ocean, while ℓ rapidly decreases close to the bottom, as one would expect. However, in deep profiles away from the sill, the effect of topography results in the ℓ structure being unreasonably complicated as one moves towards the bottom. Values of 15 to 20 × 10<sup>−4</sup> m<sup>2</sup> s<sup>-1</sup> were obtained for <i>K</i><sub>M</sub> and <i>K</i><sub>H</sub> in deep water in the vicinity of the Lifamatola Sill. These estimates agree well with basin-scale averaged values of 13.3 × 10<sup>−4</sup> m<sup>2</sup> s<sup>-1</sup> found diagnostically for <i>K</i><sub>H</sub> in the deep Banda and Seram Seas (Gordon et al., 2003) and a value of 9.0 × 10<sup>−4</sup> m<sup>2</sup> s<sup>-1</sup> found diagnostically for <i>K</i><sub>H</sub> for the deep Banda Sea system (van Aken et al., 1988). The somewhat higher simulated values can be explained by the presence of steep topography around the sill.
Resumo:
This paper presents a detailed description of health care resource utilisation and costs of a pilot interdisciplinary health care model of palliative home care in Ontario, Canada. The descriptive evaluation entailed examining the use of services and costs of the pilot program: patient demographics, length of stay broken down by disposition (discharged, alive, death), access to services/resources, use of family physician and specialist services, and drug use. There were 434 patients included in the pilot program. Total costs were approximately CAN$2.4 million, and the cost per person amounted to approximately CAN$5586.33 with average length of stay equal to over 2 months (64.22 days). One may assume that length of stay would be influenced by the amount of service and support available. Future research might investigate whether in-home palliative home care is the most cost effective and suitable care setting for those patients requiring home care services for expected periods of time. © 2009 SAGE Publications.