37 research outputs found

    Morphologic change and the DNA contents of the testicular cell of rabbits treated with the fatty acid ex­tracted from the irradiated animals

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    1. The unsaturated fatty acid fraction (OX) from the liver of irradiated rabbits contains substance which has the same effects as X-ray irradiation on the testicular cells. 2. This substance introduced intravenously causes the degeneration of the germinal cells with the formation of giant cells or multi-nucleated cells and the mitotic abnormalities. 3. The DNA content of the cell also shows the changes exactly identical with that seen after X-ray irradiation. 4. From these results we conclude that the X-ray injury will be mainly due to the production of some toxic substance which is found in the unsaturated fatty acid fraction and severely affects the cells in mitosis and DNA metabolism.</p

    Morphologic change of Yoshida sarcoma cells and coelothelioma cells after exposing to the cell toxin from X-ray-irradiated animal

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    The unsaturated fatty acid fraction extracted from the liver of rabbit irradiated with X-rays exerts a strong cytotoxic effect on human coelothelioma cells and Yoshida sarcoma cells both in vitro and in vivo. The cell damage seems to initiate at the nucleus, finally leading to the complete cytolysis. The inhibiting effect of this substance on the mitosis of Yoshida sarcoma cells can be observed, especially marked from prophase up to metaphase giving almost the same results obtained after X-ray irradiation. From these results and the observations reported by several authors on the cell damage by X-ray irradiation, weshould call special attention to the fact that the essential mechanism of X-ray irradiation can be attributed to the cell toxin produced after the irradiation.</p

    Morphologic studies of bone marrow cells exposed to the phospholipid fraction from the liver of irradiated animal, an experiment in vitro

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    With the purpose of revealing the biological effects of the X-ray irradiation the authors extracted phospholipids from the liver of irradiated animals and proved that this substance has the action to inhibit the growth of the bone marrow cells, the motility of pseudo-eosinophilis and the erythropoiesis in tissue culture, suggesting that the injury will mainly be induced by the toxic substances produced by irradiation.</p

    Coincidence analysis to search for inspiraling compact binaries using TAMA300 and LISM data

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    Japanese laser interferometric gravitational wave detectors, TAMA300 and LISM, performed a coincident observation during 2001. We perform a coincidence analysis to search for inspiraling compact binaries. The length of data used for the coincidence analysis is 275 hours when both TAMA300 and LISM detectors are operated simultaneously. TAMA300 and LISM data are analyzed by matched filtering, and candidates for gravitational wave events are obtained. If there is a true gravitational wave signal, it should appear in both data of detectors with consistent waveforms characterized by masses of stars, amplitude of the signal, the coalescence time and so on. We introduce a set of coincidence conditions of the parameters, and search for coincident events. This procedure reduces the number of fake events considerably, by a factor 104\sim 10^{-4} compared with the number of fake events in single detector analysis. We find that the number of events after imposing the coincidence conditions is consistent with the number of accidental coincidences produced purely by noise. We thus find no evidence of gravitational wave signals. We obtain an upper limit of 0.046 /hours (CL =90= 90 %) to the Galactic event rate within 1kpc from the Earth. The method used in this paper can be applied straightforwardly to the case of coincidence observations with more than two detectors with arbitrary arm directions.Comment: 28 pages, 17 figures, Replaced with the version to be published in Physical Review

    Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004

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    We analyze the data of TAMA300 detector to search for gravitational waves from inspiraling compact star binaries with masses of the component stars in the range 1-3Msolar. In this analysis, 2705 hours of data, taken during the years 2000-2004, are used for the event search. We combine the results of different observation runs, and obtained a single upper limit on the rate of the coalescence of compact binaries in our Galaxy of 20 per year at a 90% confidence level. In this upper limit, the effect of various systematic errors such like the uncertainty of the background estimation and the calibration of the detector's sensitivity are included.Comment: 8 pages, 4 Postscript figures, uses revtex4.sty The author list was correcte

    The Japanese space gravitational wave antenna; DECIGO

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    DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. DECIGO is expected to open a new window of observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing various mysteries of the universe such as dark energy, formation mechanism of supermassive black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of three drag-free spacecraft, whose relative displacements are measured by a differential Fabry– Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre- DECIGO first and finally DECIGO in 2024

    DECIGO pathfinder

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    DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article

    Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses

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    We present data-analysis schemes and results of observations with the TAMA300 gravitational-wave detector, targeting burst signals from stellar-core collapse events. In analyses for burst gravitational waves, the detection and fake-reduction schemes are different from well-investigated ones for a chirp-wave analysis, because precise waveform templates are not available. We used an excess-power filter for the extraction of gravitational-wave candidates, and developed two methods for the reduction of fake events caused by non-stationary noises of the detector. These analysis schemes were applied to real data from the TAMA300 interferometric gravitational wave detector. As a result, fake events were reduced by a factor of about 1000 in the best cases. The resultant event candidates were interpreted from an astronomical viewpoint. We set an upper limit of 2.2x10^3 events/sec on the burst gravitational-wave event rate in our Galaxy with a confidence level of 90%. This work sets a milestone and prospects on the search for burst gravitational waves, by establishing an analysis scheme for the observation data from an interferometric gravitational wave detector
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