511 research outputs found

    On patient-specific wall stress analysis in abdominal aortic aneurysms

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    Halo-Galaxy Lensing: A Full Sky Approach

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    The halo-galaxy lensing correlation function or the average tangential shear profile over sampled halos is a very powerful means of measuring the halo masses, the mass profile, and the halo-mass correlation function of very large separations in the linear regime. We reformulate the halo-galaxy lensing correlation in harmonic space. We find that, counter-intuitively, errors in the conventionally used flat-sky approximation remain at a % level even at very small angles. The errors increase at larger angles and for lensing halos at lower redshifts: the effect is at a few % level at the baryonic acoustic oscillation scales for lensing halos of z∼0.2z\sim 0.2, and comparable with the effect of primordial non-Gaussianity with fNL∼10f_{\rm NL}\sim 10 at large separations. Our results allow to readily estimate/correct for the full-sky effect on a high-precision measurement of the average shear profile available from upcoming wide-area lensing surveys.Comment: 12 pages, 4 figure

    Constraints on Cosmology from the Cosmic Microwave Background Power Spectrum of the 2500 deg^2 SPT-SZ Survey

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    We explore extensions to the ΛCDM cosmology using measurements of the cosmic microwave background (CMB) from the recent SPT-SZ survey, along with data from WMAP7 and measurements of H_0 and baryon acoustic oscillation (BAO). We check for consistency within ΛCDM between these data sets, and find some tension. The CMB alone gives weak support to physics beyond ΛCDM, due to a slight trend relative to ΛCDM of decreasing power toward smaller angular scales. While it may be due to statistical fluctuation, this trend could also be explained by several extensions. We consider running of the primordial spectral index (dn_s /d ln k), as well as two extensions that modify the damping tail power (the primordial helium abundance Y_p and the effective number of neutrino species N_(eff)) and one that modifies the large-scale power due to the integrated Sachs-Wolfe effect (the sum of neutrino masses ∑m_ν). These extensions have similar observational consequences and are partially degenerate when considered simultaneously. Of the six one-parameter extensions considered, we find CMB to have the largest preference for dn_s/d ln k with –0.046 0 from CMB+BAO+H_0 + SPT_(CL). The median value is (0.32 ± 0.11) eV, a factor of six above the lower bound set by neutrino oscillation observations. All data sets except H_0 show some preference for massive neutrinos; data combinations including H_0 favor nonzero masses only if BAO data are also included. We also constrain the two-parameter extensions N_(eff) + ∑m_ν and N_(eff) + Y_p to explore constraints on additional light species and big bang nucleosynthesis, respectively

    The common characteristics and outcomes of multidisciplinary collaboration in primary health care:A systematic literature review

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    <p><strong>Introduction: </strong>Research on collaboration in primary care focuses on specific diseases or types of collaboration. We investigate the effects of such collaboration by bringing together the results of scientific studies.</p><p><br /><strong>Theory and methods: </strong>We conducted a systematic literature review of PubMed, CINAHL, Cochrane and EMBASE. The review was restricted to publications that test outcomes of multidisciplinary collaboration in primary care in high-income countries. A conceptual model is used to structure the analysis.</p><p><br /><strong>Results: </strong>Fifty-one studies comply with the selection criteria about collaboration in primary care. Approximately half of the 139 outcomes in these studies is non-significant. Studies among older patients, in particular, report non-significant outcomes (<span class="italic">p</span> &lt; .05). By contrast, a higher proportion of significant results were found in studies that report on clinical outcomes.</p><p><br /><strong>Conclusions and discussion: </strong>This review shows a large diversity in the types of collaboration in primary care; and also thus a large proportion of outcomes do not seem to be positively affected by collaboration. Both the characteristics of the structure of the collaboration and the collaboration processes themselves affect the outcomes. More research is necessary to understand the mechanism behind the success of collaboration, especially on the exact nature of collaboration and the context in which collaboration takes place.</p><p> </p

    Solvable K-essence Cosmologies and Modified Chaplygin Gas Unified Models of Dark Energy and Dark Matter

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    This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable k-essence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the parameter nn. The graphical behavior of these equations are also discussed by using power law form of potential. The relationship between k-essence and modified Chaplygin gas model shows viable results in the dark energy scenario. We conclude that the universe behaves as a cosmological constant, quintessence phase or phantom phase depending upon nn.Comment: 14 pages, 6 figure

    Exploiting Cross Correlations and Joint Analyses

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    In this report, we present a wide variety of ways in which information from multiple probes of dark energy may be combined to obtain additional information not accessible when they are considered separately. Fundamentally, because all major probes are affected by the underlying distribution of matter in the regions studied, there exist covariances between them that can provide information on cosmology. Combining multiple probes allows for more accurate (less contaminated by systematics) and more precise (since there is cosmological information encoded in cross-correlation statistics) measurements of dark energy. The potential of cross-correlation methods is only beginning to be realized. By bringing in information from other wavelengths, the capabilities of the existing probes of dark energy can be enhanced and systematic effects can be mitigated further. We present a mixture of work in progress and suggestions for future scientific efforts. Given the scope of future dark energy experiments, the greatest gains may only be realized with more coordination and cooperation between multiple project teams; we recommend that this interchange should begin sooner, rather than later, to maximize scientific gains.Comment: Report from the "Dark Energy and CMB" working group for the American Physical Society's Division of Particles and Fields long-term planning exercise ("Snowmass"

    A multi-method assessment of attentional processes in chronic, treatment-resistant depression

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    Contains fulltext : 233751.pdf (Publisher’s version ) (Open Access)Attentional deficits as well as attentional biases towards negative material are related to major depression and might maintain chronicity. However, studies investigating attentional deficits and attentional biases in chronic, treatment-resistant depressed are lacking. The aim of the current study was to compare measures of attentional deficits and attentional bias between chronic, treatment-resistant depressed outpatients and never-depressed control participants. Attentional deficits were assessed with the attentional control scale (ACS) and the Stroop Color naming task. Attentional bias was measured with the exogenous cueing task (ECT) and an emotional Stroop task. Chronic, treatment-resistant depressed patients (n=80) showed significantly more attentional deficits than never-depressed controls (n=113) on the ACS and Stroop color-naming task. However, in contrast with hypotheses, no differences were found between chronic, treatment-resistant depressed patients and never-depressed individuals on the ECT or emotional Stroop task. The current findings indicate that chronic, treatment-resistant depressed patients present attentional deficits. The results however question whether this patient group shows attentional biases for negative material. Future research should include comparisons of chronic, treatment-resistant and non-chronically depressed patients. If replicated, these current results might indicate that focusing on improving attentional deficits could be a more promising target for treatment than addressing attentional biases.9 p

    Reducing Zero-point Systematics in Dark Energy Supernova Experiments

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    We study the effect of filter zero-point uncertainties on future supernova dark energy missions. Fitting for calibration parameters using simultaneous analysis of all Type Ia supernova standard candles achieves a significant improvement over more traditional fit methods. This conclusion is robust under diverse experimental configurations (number of observed supernovae, maximum survey redshift, inclusion of additional systematics). This approach to supernova fitting considerably eases otherwise stringent mission calibration requirements. As an example we simulate a space-based mission based on the proposed JDEM satellite; however the method and conclusions are general and valid for any future supernova dark energy mission, ground or space-based.Comment: 30 pages,8 figures, 5 table, one reference added, submitted to Astroparticle Physic

    Detailed examination of lymph nodes improves prognostication in colorectal cancer

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    Up to 30% of stage II patients with curatively resected colorectal cancer (CRC) will develop disease recurrence. We evaluated whether examination of lymph nodes by multilevel sectioning and immunohistochemical staining can improve prognostication. Lymph nodes (n = 780) from 36 CRC patients who had developed disease recurrence (cases) and 72 patients who showed no recurrence of disease for at least 5 years (controls) were analyzed. Sections of 4 levels at 200-mu m interval were immunohistochemically stained for cytokeratin expression. The first level was analyzed by conventional and automated microscopy, and the 3 following levels were analyzed by automated microscopy for the presence of tumor cells. Overall, cases showed more micrometastases (3 patients) than controls (1 patient). Analysis of a second level led to the additional detection of 1 patient with micrometastases (case) and 1 patient with macrometastasis (case). Examining more levels only led to additional isolated tumor cells, which were equally divided between cases and controls. Likewise, automated microscopy resulted only in detection of additional isolated tumor cells when compared with conventional microscopy. In multivariate analysis, micrometastases [odds ratio (OR) 26.3, 95% confidence interval (CI) 1.9-364.8, p = 0.015], T4 stage (OR 4.8, 95% CI 1.4-16.7, p = 0.013) and number of lymph nodes (OR 0.9, 95% CI 0.8-1.0, p = 0.028) were independent predictors for disease recurrence. Lymph node analysis of 2 levels and immunohistochemical staining add to the detection of macrometastases and micrometastases in CRC. Micrometastases were found to be an independent predictor of disease recurrence. Isolated tumor cells were of no prognostic significance.</p

    Constraints on early dark energy from CMB lensing and weak lensing tomography

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    Dark energy can be studied by its influence on the expansion of the Universe as well as on the growth history of the large-scale structure. In this paper, we follow the growth of the cosmic density field in early dark energy cosmologies by combining observations of the primary CMB temperature and polarisation power spectra at high redshift, of the CMB lensing deflection field at intermediate redshift and of weak cosmic shear at low redshifts for constraining the allowed amount of early dark energy. We present these forecasts using the Fisher-matrix formalism and consider the combination of Planck-data with the weak lensing survey of Euclid. We find that combining these data sets gives powerful constraints on early dark energy and is able to break degeneracies in the parameter set inherent to the various observational channels. The derived statistical 1-sigma-bound on the early dark energy density parameter is sigma(Omega_d^e)=0.0022 which suggests that early dark energy models can be well examined in our approach. In addition, we derive the dark energy figure of merit for the considered dark energy parameterisation and comment on the applicability of the growth index to early dark energy cosmologies.Comment: 25 pages, 14 figures, 3 tables; v2: very minor additions, updated to match version to be published in JCA
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