236 research outputs found
The X-Linked Inhibitor of Apoptosis Protein Inhibitor Embelin Suppresses Inflammation and Bone Erosion in Collagen Antibody Induced Arthritis Mice
Copyright © 2015 Anak A. S. S. K. Dharmapatni et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Objective. To investigate the effect of Embelin, an inhibitor of X-Linked Inhibitor of Apoptosis Protein (XIAP), on inflammation and bone erosion in a collagen antibody induced arthritis (CAIA) in mice. Methods. Four groups of mice ( per group) were allocated: CAIA untreated mice, CAIA treated with Prednisolone (10 mg/kg/day), CAIA treated with low dose Embelin (30 mg/kg/day), and CAIA treated with high dose Embelin (50 mg/kg/day). Joint inflammation was evaluated using clinical paw score and histological assessments. Bone erosion was assessed using micro-CT, tartrate resistant acid phosphatase (TRAP) staining, and serum carboxy-terminal collagen crosslinks (CTX-1) ELISA. Immunohistochemistry was used to detect XIAP protein. TUNEL was performed to identify apoptotic cells. Results. Low dose, but not high dose Embelin, suppressed inflammation as reflected by lower paw scores () and lower histological scores for inflammation. Low dose Embelin reduced serum CTX-1 () and demonstrated lower histological score and TRAP counting, and slightly higher bone volume as compared to CAIA untreated mice. XIAP expression was not reduced but TUNEL positive cells were more abundant in Embelin treated CAIA mice. Conclusion. Low dose Embelin suppressed inflammation and serum CTX-1 in CAIA mice, indicating a potential use for Embelin to treat pathological bone loss
The status of GEO 600
The GEO 600 laser interferometer with 600m armlength is part of a worldwide network of gravitational wave detectors. GEO 600 is unique in having advanced multiple pendulum suspensions with a monolithic last stage and in employing a signal recycled optical design. This paper describes the recent commissioning of the interferometer and its operation in signal recycled mode
Status of the GEO600 gravitational wave detector
The GEO600 laser interferometric gravitational wave detector is approaching the end of its commissioning phase which started in 1995.During a test run in January 2002 the detector was operated for 15 days in a power-recycled michelson configuration. The detector and environmental data which were acquired during this test run were used to test the data analysis code. This paper describes the subsystems of GEO600, the status of the detector by August 2002 and the plans towards the first science run
Setting upper limits on the strength of periodic gravitational waves from PSR J1939+2134 using the first science data from the GEO 600 and LIGO detectors
Data collected by the GEO 600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar's gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar's equatorial ellipticity
Upper limits on the strength of periodic gravitational waves from PSR J1939+2134
The first science run of the LIGO and GEO gravitational wave detectors
presented the opportunity to test methods of searching for gravitational waves
from known pulsars. Here we present new direct upper limits on the strength of
waves from the pulsar PSR J1939+2134 using two independent analysis methods,
one in the frequency domain using frequentist statistics and one in the time
domain using Bayesian inference. Both methods show that the strain amplitude at
Earth from this pulsar is less than a few times .Comment: 7 pages, 1 figure, to appear in the Proceedings of the 5th Edoardo
Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July
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Searching for gravitational waves from known pulsars
We present upper limits on the amplitude of gravitational waves from 28
isolated pulsars using data from the second science run of LIGO. The results
are also expressed as a constraint on the pulsars' equatorial ellipticities. We
discuss a new way of presenting such ellipticity upper limits that takes
account of the uncertainties of the pulsar moment of inertia. We also extend
our previous method to search for known pulsars in binary systems, of which
there are about 80 in the sensitive frequency range of LIGO and GEO 600.Comment: Accepted by CQG for the proceeding of GWDAW9, 7 pages, 2 figure
Improving the sensitivity to gravitational-wave sources by modifying the input-output optics of advanced interferometers
We study frequency dependent (FD) input-output schemes for signal-recycling
interferometers, the baseline design of Advanced LIGO and the current
configuration of GEO 600. Complementary to a recent proposal by Harms et al. to
use FD input squeezing and ordinary homodyne detection, we explore a scheme
which uses ordinary squeezed vacuum, but FD readout. Both schemes, which are
sub-optimal among all possible input-output schemes, provide a global noise
suppression by the power squeeze factor, while being realizable by using
detuned Fabry-Perot cavities as input/output filters. At high frequencies, the
two schemes are shown to be equivalent, while at low frequencies our scheme
gives better performance than that of Harms et al., and is nearly fully
optimal. We then study the sensitivity improvement achievable by these schemes
in Advanced LIGO era (with 30-m filter cavities and current estimates of
filter-mirror losses and thermal noise), for neutron star binary inspirals, and
for narrowband GW sources such as low-mass X-ray binaries and known radio
pulsars. Optical losses are shown to be a major obstacle for the actual
implementation of these techniques in Advanced LIGO. On time scales of
third-generation interferometers, like EURO/LIGO-III (~2012), with
kilometer-scale filter cavities, a signal-recycling interferometer with the FD
readout scheme explored in this paper can have performances comparable to
existing proposals. [abridged]Comment: Figs. 9 and 12 corrected; Appendix added for narrowband data analysi
First upper limits from LIGO on gravitational wave bursts
We report on a search for gravitational wave bursts using data from the first
science run of the LIGO detectors. Our search focuses on bursts with durations
ranging from 4 ms to 100 ms, and with significant power in the LIGO sensitivity
band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than
1.6 events per day at 90% confidence level. This result is interpreted in terms
of the detection efficiency for ad hoc waveforms (Gaussians and sine-Gaussians)
as a function of their root-sum-square strain h_{rss}; typical sensitivities
lie in the range h_{rss} ~ 10^{-19} - 10^{-17} strain/rtHz, depending on
waveform. We discuss improvements in the search method that will be applied to
future science data from LIGO and other gravitational wave detectors.Comment: 21 pages, 15 figures, accepted by Phys Rev D. Fixed a few small typos
and updated a few reference
Analysis of LIGO data for gravitational waves from binary neutron stars
We report on a search for gravitational waves from coalescing compact binary
systems in the Milky Way and the Magellanic Clouds. The analysis uses data
taken by two of the three LIGO interferometers during the first LIGO science
run and illustrates a method of setting upper limits on inspiral event rates
using interferometer data. The analysis pipeline is described with particular
attention to data selection and coincidence between the two interferometers. We
establish an observational upper limit of 1.7 \times 10^{2}M_\odot$.Comment: 17 pages, 9 figure
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