222 research outputs found
Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004
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
Analysis of risk factors of long-term complications in congenital diaphragmatic hernia: A single institution\u27s experience
ObjectiveTo establish better management practices to reduce morbidities in survivors with congenital diaphragmatic hernia (CDH).MethodsOf 60 patients treated for CDH at our institution between 1991 and 2011, 49 patients without severe anomalies were retrospectively reviewed.ResultsSince 2004, gentle ventilation (GV) has been the main treatment for CDH. Patients were divided into the following two groups: the non-GV group (n = 29) who were treated before GV treatment was implemented, and the GV group (n = 20). The overall survival rate was 62.1% (18/29) and 95% (19/20) in the non-GV and GV groups, respectively (p = 0.016). Despite the high survival rate, the incidence of long-term complications in survivors was still high (14/19, 73.7%) in the GV group. In the GV group, liver-up (p = 0.106) and the need for patch repair (p = 0.257) tended to be associated with the development of long-term complications, but did not reach statistical significance. The presence of perioperative complications was associated with the development of long-term complications (p = 0.045) in the GV group.ConclusionPatients who developed short-term complications seemed to be at risk of long-term complications. Therefore, to minimize long-term morbidities in CDH survivors, the prevention of short-term complications might be important
The Japanese space gravitational wave antenna; DECIGO
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
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
Tumor-containing CEA in Colon Cancers
Carcinoembryonic antigen (CEA) in serum and fresh cancer tissue taken at surgery was measured and analyzed in terms of the disease stage. The CEA level in serum (s-CEA ) has become higher with advance in the disease stage. However, in stage V it was lowered as well as CEA level in cancer mass (ca-CEA). It is suggested that S-CEA is influenced by cancer invasion into the vessel wall, tumor necrosis and/or degeneration which ca-CEA may well be migrated from the tumor cells
Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses
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
Current status of space gravitational wave antenna DECIGO and B-DECIGO
Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is the
future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO
aims at the detection of primordial gravitational waves, which could be
produced during the inflationary period right after the birth of the universe.
There are many other scientific objectives of DECIGO, including the direct
measurement of the acceleration of the expansion of the universe, and reliable
and accurate predictions of the timing and locations of neutron star/black hole
binary coalescences. DECIGO consists of four clusters of observatories placed
in the heliocentric orbit. Each cluster consists of three spacecraft, which
form three Fabry-Perot Michelson interferometers with an arm length of 1,000
km. Three clusters of DECIGO will be placed far from each other, and the fourth
cluster will be placed in the same position as one of the three clusters to
obtain the correlation signals for the detection of the primordial
gravitational waves. We plan to launch B-DECIGO, which is a scientific
pathfinder of DECIGO, before DECIGO in the 2030s to demonstrate the
technologies required for DECIGO, as well as to obtain fruitful scientific
results to further expand the multi-messenger astronomy.Comment: 10 pages, 3 figure
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