110 research outputs found
Cosmic Microwave Background-Weak Lensing Correlation: Analytical and Numerical Study of Nonlinearity and Implications for Dark Energy
Evolution of density fluctuations yields secondary anisotropies in the cosmic microwave background ( CMB), which are correlated with the same density fluctuations that can be measured by weak lensing (WL) surveys. We study the CMB-WL correlation induced by the integrated Sachs-Wolfe (ISW) effect and its nonlinear extension, the Rees-Sciama (RS) effect, using analytical models as well as N-body simulations. We show that an analytical model based on the time derivative of matter power spectrum agrees with simulations. All-sky cosmic-variance-limited CMB and WL surveys allow us to measure the correlation from the nonlinear RS effect with high significance (50 sigma) for l(max) = 10(4) whereas forthcoming missions such as Planck and LSST are expected to yield 4 l p 10 1.5 sigma detections, on the assumption of that the point-source contributions are negligible. We find that the CMB-WL correlation has a characteristic scale which is sensitive to the nature of dark energy.Alfred P. Sloan FellowshipAstronom
Increased Interleukin-8 in Epithelial Lining Fluid of Collapsed Lungs During One-Lung Ventilation for Thoracotomy
The present study was designed to evaluate inflammatory changes in collapsed lungs during one-lung ventilation using the assistance of a bronchoscopic microsampling probe. Serial albumin and interleukin (IL)-8 concentrations in epithelial lining fluid (ELF) were measured in seven patients undergoing resection of lung tumors. The samples were taken after induction of anesthesia (baseline), 30 min after one-lung ventilation was started (point 2), just before resuming two-lung ventilation (point 3), and 30 min after two-lung ventilation was restarted (point 4). The albumin and IL-8 concentrations in ELF were significantly increased at point 2 and point 3, respectively, and remained to be high, compared to the baseline. The increase in IL-8 at point 3 was correlated with the interval of one-lung ventilation; however, none developed specific acute lung injury. These findings suggest that inflammatory changes can occur on the epithelium of a collapsed lung even in patients who underwent successful and standard thoracic surgery.ArticleINFLAMMATION. 35(6):1844-1850 (2012)journal articl
Non-Gaussian Error Contribution to Likelihood Analysis of the Matter Power Spectrum
We study the sample variance of the matter power spectrum for the standard
Lambda Cold Dark Matter universe. We use a total of 5000 cosmological N-body
simulations to study in detail the distribution of best-fit cosmological
parameters and the baryon acoustic peak positions. The obtained distribution is
compared with the results from the Fisher matrix analysis with and without
including non-Gaussian errors. For the Fisher matrix analysis, we compute the
derivatives of the matter power spectrum with respect to cosmological
parameters using directly full nonlinear simulations. We show that the
non-Gaussian errors increase the unmarginalized errors by up to a factor 5 for
k_{max}=0.4h/Mpc if there is only one free parameter provided other parameters
are well determined by external information. On the other hand, for
multi-parameter fitting, the impact of the non-Gaussian errors is significantly
mitigated due to severe parameter degeneracies in the power spectrum. The
distribution of the acoustic peak positions is well described by a Gaussian
distribution, with its width being consistent with the statistical interval
predicted from the Fisher matrix. We also examine systematic bias in the
best-fit parameter due to the non-Gaussian errors. The bias is found to be
smaller than the 1 sigma statistical error for both the cosmological parameters
and the acoustic scale positions.Comment: 12 pages, 10 figures, accepted for publication in ApJ, minor change
High-precision predictions for the acoustic scale in the non-linear regime
We measure shifts of the acoustic scale due to nonlinear growth and redshift
distortions to a high precision using a very large volume of
high-force-resolution simulations. We compare results from various sets of
simulations that differ in their force, volume, and mass resolution. We find a
consistency within 1.5-sigma for shift values from different simulations and
derive shift alpha(z) -1 = (0.300\pm 0.015)% [D(z)/D(0)]^{2} using our fiducial
set. We find a strong correlation with a non-unity slope between shifts in real
space and in redshift space and a weak correlation between the initial redshift
and low redshift. Density-field reconstruction not only removes the mean shifts
and reduces errors on the mean, but also tightens the correlations: after
reconstruction, we recover a slope of near unity for the correlation between
the real and redshift space and restore a strong correlation between the low
and the initial redshifts. We derive propagators and mode-coupling terms from
our N-body simulations and compared with Zeldovich approximation and the shifts
measured from the chi^2 fitting, respectively. We interpret the propagator and
the mode-coupling term of a nonlinear density field in the context of an
average and a dispersion of its complex Fourier coefficients relative to those
of the linear density field; from these two terms, we derive a signal-to-noise
ratio of the acoustic peak measurement. We attempt to improve our
reconstruction method by implementing 2LPT and iterative operations: we obtain
little improvement. The Fisher matrix estimates of uncertainty in the acoustic
scale is tested using 5000 (Gpc/h)^3 of cosmological PM simulations from
Takahashi et al. (2009). (abridged)Comment: Revised to match the version in print: a new figure (figure 6) is
added and Section 5 (and figure 8) is revised to include more details. 19
emulated apj pages with 13 figures and 3 table
Scaling Up Towards International Targets for AIDS, Tuberculosis, and Malaria: Contribution of Global Fund-Supported Programs in 2011–2015
OBJECTIVE: The paper projects the contribution to 2011-2015 international targets of three major pandemics by programs in 140 countries funded by the Global Fund to Fight AIDS, Tuberculosis and Malaria, the largest external financier of tuberculosis and malaria programs and a major external funder of HIV programs in low and middle income countries. DESIGN: Estimates, using past trends, for the period 2011-2015 of the number of persons receiving antiretroviral (ARV) treatment, tuberculosis case detection using the internationally approved DOTS strategy, and insecticide-treated nets (ITNs) to be delivered by programs in low and middle income countries supported by the Global Fund compared to international targets established by UNAIDS, Stop TB Partnership, Roll Back Malaria Partnership and the World Health Organisation. RESULTS: Global Fund-supported programs are projected to provide ARV treatment to 5.5-5.8 million people, providing 30%-31% of the 2015 international target. Investments in tuberculosis and malaria control will enable reaching in 2015 60%-63% of the international target for tuberculosis case detection and 30%-35% of the ITN distribution target in sub-Saharan Africa. CONCLUSION: Global Fund investments will substantially contribute to the achievement by 2015 of international targets for HIV, TB and malaria. However, additional large scale international and domestic financing is needed if these targets are to be reached by 2015
RNA editing facilitates the enhanced production of neoantigens during the simultaneous administration of oxaliplatin and radiotherapy in colorectal cancer
Most cases of colorectal cancers (CRCs) are microsatellite stable (MSS), which frequently demonstrate lower response rates to immune checkpoint inhibitors (ICIs). RNA editing produces neoantigens by altering amino acid sequences. In this study, RNA editing was induced artificially by chemoradiation therapy (CRT) to generate neoantigens in MSS CRCs. Altogether, 543 CRC specimens were systematically analyzed, and the expression pattern of ADAR1 was investigated. In vitro and in vivo experiments were also performed. The RNA editing enzyme ADAR1 was upregulated in microsatellite instability-high CRCs, leading to their high affinity for ICIs. Although ADAR1 expression was low in MSS CRC, CRT including oxaliplatin (OX) treatment upregulated RNA editing levels by inducing ADAR1. Immunohistochemistry analyses showed the upregulation of ADAR1 in patients with CRC treated with CAPDX (capecitabine +OX) radiation therapy relative to ADAR1 expression in patients with CRC treated only by surgery (p <0.001). Compared with other regimens, CRT with OX effectively induced RNA editing in MSS CRC cell lines (HT29 and Caco2, p <0.001) via the induction of type 1 interferon-triggered ADAR1 expression. CRT with OX promoted the RNA editing of cyclin I, a neoantigen candidate. Neoantigens can be artificially induced by RNA editing via an OX-CRT regimen. CRT can promote proteomic diversity via RNA editing
Framework for evaluating the health impact of the scale-up of malaria control interventions on all-cause child mortality in Sub-Saharan Africa
Concerted efforts from national and international partners have scaled up malaria control interventions, including insecticide-treated nets, indoor residual spraying, diagnostics, prompt and effective treatment of malaria cases, and intermittent preventive treatment during pregnancy in sub-Saharan Africa (SSA). This scale-up warrants an assessment of its health impact to guide future efforts and investments; however, measuring malaria-specific mortality and the overall impact of malaria control interventions remains challenging. In 2007, Roll Back Malaria's Monitoring and Evaluation Reference Group proposed a theoretical framework for evaluating the impact of full-coverage malaria control interventions on morbidity and mortality in high-burden SSA countries. Recently, several evaluations have contributed new ideas and lessons to strengthen this plausibility design. This paper harnesses that new evaluation experience to expand the framework, with additional features, such as stratification, to examine subgroups most likely to experience improvement if control programs are working; the use of a national platform framework; and analysis of complete birth histories from national household surveys. The refined framework has shown that, despite persisting data challenges, combining multiple sources of data, considering potential contributions from both fundamental and proximate contextual factors, and conducting subnational analyses allows identification of the plausible contributions of malaria control interventions on malaria morbidity and mortality
Initial evidence of reduction of malaria cases and deaths in Rwanda and Ethiopia due to rapid scale-up of malaria prevention and treatment
<p>Abstract</p> <p>Background</p> <p>An increasing number of malaria-endemic African countries are rapidly scaling up malaria prevention and treatment. To have an initial estimate of the impact of these efforts, time trends in health facility records were evaluated in selected districts in Ethiopia and Rwanda, where long-lasting insecticidal nets (LLIN) and artemisinin-based combination therapy (ACT) had been distributed nationwide by 2007.</p> <p>Methods</p> <p>In Ethiopia, a stratified convenience sample covered four major regions where (moderately) endemic malaria occurs. In Rwanda, two districts were sampled in all five provinces, with one rural health centre and one rural hospital selected in each district. The main impact indicator was percentage change in number of in-patient malaria cases and deaths in children < 5 years old prior to (2001–2005/6) and after (2007) nationwide implementation of LLIN and ACT.</p> <p>Results</p> <p>In-patient malaria cases and deaths in children < 5 years old in Rwanda fell by 55% and 67%, respectively, and in Ethiopia by 73% and 62%. Over this same time period, non-malaria cases and deaths generally remained stable or increased.</p> <p>Conclusion</p> <p>Initial evidence indicated that the combination of mass distribution of LLIN to all children < 5 years or all households and nationwide distribution of ACT in the public sector was associated with substantial declines of in-patient malaria cases and deaths in Rwanda and Ethiopia. Clinic-based data was a useful tool for local monitoring of the impact of malaria programmes.</p
Probability Distribution Functions of Cosmological Lensing: Convergence, Shear, and Magnification
We perform high resolution ray-tracing simulations to investigate probability
distribution functions (PDFs) of lensing convergence, shear, and magnification
on distant sources up to the redshift of . We pay particular attention
to the shot noise effect in -body simulations by explicitly showing how it
affects the variance of the convergence. We show that the convergence and
magnification PDFs are closely related with each other via the approximate
relation , which can reproduce the behavior of PDFs
surprisingly well up to the high magnification tail. The mean convergence
measured in the source plane is found to be systematically negative, rather
than zero as often assumed, and is correlated with the convergence variance. We
provide simple analytical formulae for the PDFs, which reproduce simulated PDFs
reasonably well for a wide range of redshifts and smoothing sizes. As explicit
applications of our ray-tracing simulations, we examine the strong lensing
probability and the magnification effects on the luminosity functions of
distant galaxies and quasars.Comment: 15 pages, 19 figures, minor changes, references added, accepted for
publication in Ap
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