Characteristic Scales of Baryon Acoustic Oscillations from Perturbation Theory: Non-linearity and Redshift-Space Distortion Effects

An acoustic oscillation of the primeval photon-baryon fluid around the decoupling time imprints a characteristic scale in the galaxy distribution today, known as the baryon acoustic oscillation (BAO) scale. Several on-going and/or future galaxy surveys aim at detecting and precisely determining the BAO scale so as to trace the expansion history of the universe. We consider nonlinear and redshift-space distortion effects on the shifts of the BAO scale in $k$-space using perturbation theory. The resulting shifts are indeed sensitive to different choices of the definition of the BAO scale, which needs to be kept in mind in the data analysis. We present a toy model to explain the physical behavior of the shifts. We find that the BAO scale defined as in Percival et al. (2007) indeed shows very small shifts ($\lesssim$ 1%) relative to the prediction in {\it linear theory} in real space. The shifts can be predicted accurately for scales where the perturbation theory is reliable.Comment: 21 pages, 9 figures, references and supplementary sections added, accepted for publication in PAS

Galaxy clustering constraints on deviations from Newtonian gravity at cosmological scales II: Perturbative and numerical analyses of power spectrum and bispectrum

We explore observational constraints on possible deviations from Newtonian gravity by means of large-scale clustering of galaxies. We measure the power spectrum and the bispectrum of Sloan Digital Sky Survey galaxies and compare the result with predictions in an empirical model of modified gravity. Our model assumes an additional Yukawa-like term with two parameters that characterize the amplitude and the length scale of the modified gravity. The model predictions are calculated using two methods; the second-order perturbation theory and direct N-body simulations. These methods allow us to study non-linear evolution of large-scale structure. Using the simulation results, we find that perturbation theory provides reliable estimates for the power spectrum and the bispectrum in the modified Newtonian model. We also construct mock galaxy catalogues from the simulations, and derive constraints on the amplitude and the length scale of deviations from Newtonian gravity. The resulting constraints from power spectrum are consistent with those obtained in our earlier work, indicating the validity of the previous empirical modeling of gravitational nonlinearity in the modified Newtonian model. If linear biasing is adopted, the bispectrum of the SDSS galaxies yields constraints very similar to those from the power spectrum. If we allow for the nonlinear biasing instead, we find that the ratio of the quadratic to linear biasing coefficients, b_2/b_1, should satisfy -0.4 < b_2/b_1<0.3 in the modified Newtonian model.Comment: 12 pages, 7 figure

Jitteriness/anxiety syndrome caused by coadministration of celecoxib, a selective COX‐2 inhibitor, with escitalopram and trazodone in a patient with depression and spondylolisthesis

Abstract Antidepressant‐induced jitteriness/anxiety syndrome is characterized as anxiety, agitation, panic attacks, insomnia, irritability, hostility, aggressiveness, impulsivity, akathisia, and (hypo)mania, which appear immediately after initiation or increased dosage of an antidepressant. This report describes a case of the jitteriness/anxiety syndrome caused by the coadministration of celecoxib with escitalopram and trazodone in a patient with depression and spondylolisthesis. The depression of a patient, a woman in her 60 s, had been in remission at least for 5 years under treatment using escitalopram and trazodone. Immediately after coadministration of celecoxib because of her buttock and limb pain, she showed anxiety, agitation, akathisia, insomnia, irritability, aggressiveness, impulsivity, and hypomania. These symptoms disappeared after the discontinuation of celecoxib. The present case suggests that coadministration of celecoxib with escitalopram and trazodone can cause the jitteriness/anxiety syndrome, presumably via a pharmacokinetic interaction of celecoxib with these antidepressants and/or the effects of celecoxib on serotonergic neurotransmission

Relationship between interpersonal sensitivity and leukocyte telomere length

Abstract Background Telomeres are repetitive DNA sequences located at the ends of chromosomes, and telomere length represents a biological marker for cellular aging. Interpersonal sensitivity, excessive sensitivity to the behavior and feelings of others, is one of the vulnerable factors to depression. In the present study, we examined the effect of interpersonal sensitivity on telomere length in healthy subjects. Methods The subjects were 159 unrelated healthy Japanese volunteers. Mean age ± SD (range) of the subjects was 42.3 ± 7.8 (30–61) years. Interpersonal sensitivity was assessed by the Japanese version of the Interpersonal Sensitivity Measure (IPSM). Leukocyte telomere length was determined by a quantitative real-time PCR method. Results Higher scores of the total IPSM were significantly (β = −0.163, p = 0.038) related to shorter telomere length. In the sub-scale analysis, higher scores of timidity were significantly (β = −0.220, p = 0.044) associated with shorter telomere length. Conclusions The present study suggests that subjects with higher interpersonal sensitivity have shorter leukocyte telomere length, implying that interpersonal sensitivity has an impact on cellular aging

Modeling Nonlinear Evolution of Baryon Acoustic Oscillations: Convergence Regime of IV-Body Simulations and Analytic Models

We used a series of cosmological N-body simulations and various analytic models to study the evolution of the matter power spectrum in real space in a A cold dark matter universe. We compared the results of A 7-body simulations against three analytical model predictions; standard perturbation theory, renormalized perturbation theory, and a closure approximation. We included the effects from a finite simulation box size under comparison. We determined the values of the maximum wavenumbers, klim1% and klim3%, below which the analytic models and the simulation results agree with accuracy to within 1 and 3 percent. We then provided a simple empirical function that describes the convergence regime determined by comparisons between our simulations and the analytical models. We found that if we use the Fourier modes within the convergence regime alone, the characteristic scale of baryon acoustic oscillations can be determined with an accuracy of 1% from future surveys with a volume of a few h-3Gpc3 at z ~ 1 or z ~ 3 in the absence of any systematic distortion of the power spectrum