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ABSTRACT: The statistics of isothermal lines and loops of the Cosmic Microwave
Background (CMB) radiation on the sky map is studied and the fractal structure
is confirmed in the radiation temperature fluctuation. We estimate the fractal
exponents, such as the fractal dimension $D_{\mathrm{e}}$ of the entire pattern
of isothermal lines, the fractal dimension $D_{\mathrm{c}}$ of a single
isothermal line, the exponent $\zeta$ in Kor\v{c}ak's law for the size
distribution of isothermal loops, the two kind of Hurst exponents,
$H_{\mathrm{e}}$ for the profile of the CMB radiation temperature, and
$H_{\mathrm{c}}$ for a single isothermal line. We also perform fractal analysis
of two artificial sky maps simulated by a standard model in physical cosmology,
the WMAP best-fit $\Lambda$ Cold Dark Matter ($\Lambda$CDM) model, and by the
Gaussian free model of rough surfaces. The temperature fluctuations of the real
CMB radiation and in the simulation using the $\Lambda$CDM model are
non-Gaussian, in the sense that the displacement of isothermal lines and loops
has an antipersistent property indicated by $H_{\mathrm{e}} \simeq 0.23 < 1/2$.
12/2010;
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ABSTRACT: We study height distributions of Japanese schoolchildren based on the statictical data which are obtained from the school health survey by the ministry of education, culture, sports, science and technology, Japan . From our analysis, it has been clarified that the distribution of height changes from the lognormal distribution to the normal distribution in the periods of puberty. Comment: 2 pages, 2 figures, submitted to J. Phys. Soc. Jpn.; resubmitted to J. Phys. Soc. Jpn. after some revision
08/2009;
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ABSTRACT: A bacterial strain isolated from the oral cavity of a healthy dog revealed an unusual colony formation in nebular appearance on agar plates. The isolated bacterial strain was Gram-positive, spore-forming rod with peritrichous flagella, and grown under aerobic conditions, but unable to grow at 45 degrees C. The strain was tentatively classified as Paenibacillus alvei according to the biochemical properties and the 16S rRNA gene sequence. The isolate exhibits collective locomotion on solid agar plates. The bacterial motility was inhibited with EDTA and was restored by adding magnesium. We concluded that magnesium ion is essential for collective locomotion of P. alvei. This suggests that EDTA is useful for inhibition of biofilm formation.
Journal of Veterinary Medical Science 03/2009; 71(2):147-53. · 0.85 Impact Factor
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Complex Sciences, First International Conference, Complex 2009, Shanghai, China, February 23-25, 2009. Revised Papers, Part 1; 01/2009
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ABSTRACT: Polar flagellated Pseudomonas aeruginosa PAO1 demonstrated extensive spreading growth in 2 days on 1.5% agar medium. Such spreading growth of P. aeruginosa PAO1 strains was absent on Luria-Bertani 1.5% agar medium, but remarkable on Davis minimal synthetic agar medium (especially that containing 0.8% sodium citrate and 1.5% Eiken agar) under aerobic 37 degrees C conditions. Analyses using isogenic mutants and complementation transformants showed that bacterial flagella and rhamnolipid contributed to the surface-spreading behavior. On the other hand, a type IV pilus-deficient pilA mutant did not lose the spreading growth activity. Flagella staining of PAO1 T cells from the frontal edge of a spreading colony showed unipolar and normal-sized rods with one or two flagella. Thus, the polar flagellate P. aeruginosa PAO1 T appears to swarm on high-agar medium by producing biosurfactant rhamnolipid and without differentiation into an elongated peritrichous hyperflagellate.
FEMS Microbiology Letters 04/2008; 280(2):169-75. · 2.04 Impact Factor
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ABSTRACT: We study rank-size distribution of cities in Japan on the basis of data analysis. From the census data after World War II, we find that the rank-size distribution of cities is composed of two parts, each of which has independent power exponent. In addition, the power exponent of the head part of the distribution changes in time and Zipf's law holds only in a restricted period. We show that Zipf's law broke down due to both of Showa and Heisei great mergers and recovered due to population growth in middle-sized cities after the great Showa merger. Comment: 6 pages, 9 figures, resubmitted to J. Phys. Soc. Jpn
02/2008;
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ABSTRACT: Anaerobiosis of Pseudomonas aeruginosa in infected organs is now gaining attention as a unique physiological feature. After anaerobic cultivation of P. aeruginosa wild type strain PAO1 T, we noticed an unexpectedly expanding colony on a 1.5% agar medium. The basic factors involved in this spreading growth were investigated by growing the PAO1 T strain and its isogenic mutants on a Davis high-agar minimal synthetic medium under various experimental conditions. The most promotive environment for this spreading growth was an O(2)-depleted 8% CO(2) condition. From mutational analysis of this spreading growth, flagella and type IV pili were shown to be ancillary factors for this bacterial activity. On the other hand, a rhamnolipid-deficient rhlA mutant TR failed to exhibit spreading growth on a high-agar medium. Complementation of the gene defect of the mutant TR with a plasmid carrying the rhlAB operon resulted in the restoration of the spreading growth. In addition, an external supply of rhamnolipid or other surfactants (surfactin from Bacillus subtilis or artificial product Tween 80) also restored the spreading growth of the mutant TR. Such activity of surfactants on bacterial spreading on a hard-agar medium was unique to P. aeruginosa under CO(2)-rich anaerobic conditions.
Microbiology and Immunology 02/2007; 51(8):703-12. · 1.30 Impact Factor
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Molecular Microbiology 02/2002; 31(4):1278 - 1279. · 5.01 Impact Factor
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ABSTRACT: Density waves of granular material (sand) flowing through a vertical pipe have been investigated. Clear density waves emerge when the cock attached to bottom end of the pipe is closed. The FFT power spectra were found to show a stable power-law form $ P(f) \sim f^{-\alpha}. $ The value of the exponent was evaluated as $\alpha \cong 4/3$. We also introduce a simple one-dimensional model which reproduces $\alpha = 4/3$ from both simulation and theoretical analysis. (to be published in Phys.Rev.Lett.) Comment: 4 pages, 4 figures, a style file
02/1998;
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ABSTRACT: Population characterizes collective behaviors of human beings. In this paper we investigate cumulative population distribution of municipalities (cities, towns, and villages) of Japan to show that each of them can be represented by a characteristic distribution function. We also introduce a numerical model for population dynamics to explain the origin of the distributions. From our analysis it has become clear that each distribution originates from the lower and upper bounds of population in the definitions of cities and towns.
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ABSTRACT: A scaling hypothesis for the standard deviation of the height of growing interfaces is proposed by extending the Family–Vicsek (FV) scaling hypothesis. A data-collapsing method is adopted for estimating values of three exponents , , and z, which characterize, respectively, the roughness, growth, and dynamic properties of growing interfaces. The estimation is carried out through , which is a function of both the time and the width of the interfaces. The advantages of the present extended scaling hypothesis are as follows: (A) The value of can be obtained even if the data for in terms of t are few so that its value is not determined precisely from the slope of the ln vs ln t plot. (B) Different scaling relations can be obtained during the time evolution of interface growth. (C) By introducing a new exponent, which represents the time dependence of for a short width, a scaling argument is possible even for growing interfaces that do not satisfy the FV scaling relation. Successful applications are carried out to a few numerical models and a paper-wetting experiment.
