708 research outputs found
Simulating the Anisotropic Clustering of Luminous Red Galaxies with Subhalos: A Direct Confrontation with Observation and Cosmological Implications
We model the apparent clustering anisotropy of Luminous Red Galaxies (LRGs)
in the Sloan Digital Sky Survey using subhalos identified in cosmological
-body simulations. We first conduct a Markov-chain Monte Carlo analysis on
the parameters characterizing subhalos hosting LRGs assuming a specific
CDM cosmology on which we run the simulations. We show that simple
models with central and satellite subhalos can explain the observed multipole
moments of the power spectrum up to hexadecapole on large scales
(). A satellite fraction of to per
cent is favored weakly depending on the detail of the model. The fraction is
shown to be robust when we adopt a more refined model based on the halo
occupation number from the literature. We then vary cosmological parameters
controlling the anisotropy in redshift-space effectively by deforming the
simulation box (the Alcock-Paczynski effect) and changing the amplitude of the
velocities (the redshift-space distortions). We demonstrate that we can
constrain the geometry of the universe, the structure growth rate, and the
parameters characterizing LRGs simultaneously. This is a step toward
cosmological analysis with realistic bias description beyond empirical bias
functions with nuisance parameters.Comment: 18 pages, 21 figures. HOD analysis added. Accepted for publication in
MNRA
Cosmology with anisotropic galaxy clustering from the combination of power spectrum and bispectrum
The apparent anisotropies of the galaxy clustering in observable redshift
space provide a unique opportunity to simultaneously probe cosmic expansion and
gravity on cosmological scales via the Alcock--Paczynski effect and
redshift-space distortions. While the improved theoretical models have been
proposed and developed to describe the apparent anisotropic clustering at
weakly non-linear scales, the applicability of these models is still limited in
the presence of the non--perturbative smearing effect caused by the randomness
of the relative velocities. Although the cosmological constraint from the
anisotropic clustering will be certainly improved with a more elaborate
theoretical model, we here consider an alternative way by using the statistical
power of both the power spectrum and bispectrum at large scales. Based on the
Fisher matrix analysis, we estimate the benefit of combining the power spectra
and bispectra, finding that the constraints on the cosmic expansion and growth
of structure will be improved by a factor of two. This compensates for the loss
of constraining power using the power spectrum alone due to the randomness of
the relative velocities.Comment: 11 pages, 8 figures, preprint number YITP-15-
Clinical evaluation of endolymphatic radiotherapy in malignant lymphoma
By endolymphatic injection of radioisotope 131I.Lipiodol, so.called endolymphatic radiotherapy, we treated 10 cases with malignant lymphoma and found a marked tumor reduction to normal size in all the 10 cases we tried. It seems that this method is one of the most effective therapeutic methods for malignant lymphoma, espe.
cially invading into the retroperitoneal lymph nodes.</p
Beyond consistency test of gravity with redshift-space distortions at quasi-linear scales
Redshift-space distortions (RSD) offer an attractive method to measure the
growth of cosmic structure on large scales, and combining with the measurement
of the cosmic expansion history, it can be used as cosmological tests of
gravity. With the advent of future galaxy redshift surveys aiming at precisely
measuring the RSD, an accurate modeling of RSD going beyond linear theory is a
critical issue in order to detect or disprove small deviations from general
relativity (GR). While several improved models of RSD have been recently
proposed based on the perturbation theory (PT), the framework of these models
heavily relies on GR. Here, we put forward a new PT prescription for RSD in
general modified gravity models. As a specific application, we present
theoretical predictions of the redshift-space power spectra in f(R) gravity
model, and compare them with N-body simulations. Using the PT template that
takes into account the effects of both modifications of gravity and RSD
properly, we successfully recover the fiducial model parameter in N-body
simulations in an unbiased way. On the other hand, we found it difficult to
detect the scale dependence of the growth rate in a model-independent way based
on GR templates.Comment: 17 pages, 9 figures, version accepted for publication in PR
Experimental studies of the endolymphatic radiotherapy
By injecting 131I-Lipiodol into lymphatics of the dorsum
of dog feet, the distribution of 13JI in the lymph nodes and other principal organs as well as its histological effect were studied periodically after the injection for the period of two months. The characteristic feature of J3JI distribution was the fact that J31I was accumulated into lymph nodes markedly higher than in any other
organs and it was retained there over a long period of time. Histological examinations of the lymph nodes revealed a marked lymphocytopenia, the loss of germinal center, practically complete loss of lymphoid elements already 5 days after injection, and marked fibrosis.
In the lung a considerable J3JI·distribution could be seen in early stage:, but with lapse of time it decreased rapidly. The distribution in other organs such as liver, spleen, bone marrow, kidney, ureter, bladder, thyroid gland, pancreas, testicles and small and large intestines
was negligible in amount, and any specific histologic effect of irradiation could not be recognized in these organs including the lung. From these results, the authors concluded that 131I-Lipiodol has a selective activity on lymph nodes by injecting it via lymphatics and it is a safe method in clinical application to treat the patients
bearing malignant lymphoma or metastatic lymph nodes.</p
Quantitative Inorganic Chromatograpy. III : Separation and Determination of Zinc in Cadmium
Chromatographic separation of zinc from cadmium and detection and determination of minute quantity 9f the former in the presence of the latter were studied. Zinc and cadmium could not be separated from each other by developing with water. When potassium iodide was added, however, cadmium, forming a complex, moved to the front of the solvent zone, while zinc remained at the original position, and they were completely separated. Thus 3 γ of zinc could be determined in the presence of 1, 000 times as much cadmium and 0.06 γ of the former could be detected in the presence of 100, 000 times as much the latter
Simultaneous constraints on the growth of structure and cosmic expansion from the multipole power spectra of the SDSS DR7 LRG sample
The anisotropic galaxy clustering on large scales provides us with a unique
opportunity to probe into the gravity theory through the redshift-space
distortions (RSDs) and the Alcock-Paczynski effect. Using the multipole power
spectra up to hexadecapole (ell=4), of the Luminous Red Galaxy (LRG) sample in
the data release 7 (DR7) of the Sloan Digital Sky Survey II (SDSS-II), we
obtain simultaneous constraints on the linear growth rate f, angular diameter
distance D_A, and Hubble parameter H at redshift z = 0.3. For this purpose, we
first extensively examine the validity of a theoretical model for the
non-linear RSDs using mock subhalo catalogues from N-body simulations, which
are constructed to match with the observed multipole power spectra. We show
that the input cosmological parameters of the simulations can be recovered well
within the error bars by comparing the multipole power spectra of our
theoretical model and those of the mock subhalo catalogues. We also carefully
examine systematic uncertainties in our analysis by testing the dependence on
prior assumption of the theoretical model and the range of wavenumbers to be
used in the fitting. These investigations validate that the theoretical model
can be safely applied to the real data. Thus, our results from the SDSS DR7 LRG
sample are robust including systematics of theoretical modeling; f(z = 0.3)
sigma_8(z = 0.3) =0.49+-0.08(stat.)+-0.04(sys.), D_A (z = 0.3)
=968+-42(stat.)+-17(sys.)[Mpc], H (z = 0.3)
=81.7+-5.0(stat.)+-3.7(sys.)[km/s/Mpc]. We believe that our method to constrain
the cosmological parameters using subhaloes catalogues will be useful for more
refined samples like CMASS and LOWZ catalogues in the Baryon Oscillation
Spectroscopic Survey in SDSS-III.Comment: accepted for publication in MNRA
Interaction between Solute Elements at Any Given Concentration in Homogeneous Multicomponent Solution
The general relationship between activities and activity coefficients based on Raoultian and Henrian reference states at any given concentration was derived from a somewhat different point of view. It was shown that Wagner type theoretical series expansion is valid at any concentrated solution, and that Taylor series expansion using the interaction parameters at constant concentration ratio is also possible. The conversion equations between several kinds of interaction parameters valid at any given concentration in a multicomponent solution were derived by the aid of Gibbs-Duhem equation and Maxwell cross differentials. In a ternary system 1-2-3, the following relations were obtained at any given concentration : where γ (or f) is the activity coefficient in mole fraction basis (or in weight percent basis), N (or X) is the mole fraction (or weight percent), M is the atomic weight and the underscript signified the component to be kept constant. It was also shown that βᵢ⁽j⁾=βj⁽i⁾ is valid at the condition Nᵢ=Nj, and consequently it follows that ∂1nγ₁/∂N₂=∂1nγ₂/∂N₁ at N₁=N₂=0.5 in a binary solution
The Anodic Oxidation of trans-Cinnamic Acid. I. The Formation of Ketone and Aldehyde Derivatives
The electrochemical oxidation of trans-cinnamic acid in a mixed aqueous solution of acetic acid and methanol containing potassium hydroxide was studied. The separation of ketones and aldehydes from the neutral materials using Girard reagent P gave benzaldehyde, tolualdehydes, acetophenone, methylacetophenones, propiophenone, phenacyl acetate, and phenacyl alcohol. The mechanism of the anodic reaction of trans-cinnamic acid has been discussed
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