665 research outputs found
Man, Communication, Being
Power Symposium, 2008. NAPS '08. 40th North American, University of Calgary, Calgary, Canada, Sept 28th to 30th, 2008Hybrid system reachability is applied to verification of fault release control in a power system. Fault release control is one strategy in emergency control and aims to mitigate an electrical stress of power system caused by disturbances. We introduce practical data in a fault release control of double machine-infinite bus (DMIB) system. The data is obtained using the RTDS and describes that the control is effective for prevention of transient instability in the DMIB system. By modeling of swing dynamics of the DMIB system as a hybrid automaton and reachability analysis of the automaton, we show that the control is correct for the prevention of transient instability
Cartilage Regeneration from Bone Marrow Cells Using RWV Bioreactor and Its Automation System for Clinical Application
Regenerative Repair of Bone Defects with Osteoinductive Hydroxyapatite Fabricated to Match the Defect and Implanted with CAD, CAM, and Computer-Assisted Surgery Systems
Regenerative repair of large bone defects currently remains a challenging issue during surgery, owing to the limited regenerative ability of the bone. To address this issue, we attempted a precise repair of a bone defect using computer-aided procedures. Using pelvic computed tomography (CT) images of beagle dogs, virtual tumors were created in the pelvis using computer-aided design (CAD), and a bone resection following the margins of the bone tumor was performed on the CAD image. Hydroxyapatite (HA) implants to fill the bone defects and implants for shape evaluation of bone resection sites were designed and produced by computer-aided manufacturing and three-dimensional printing. Subsequently, using a computer navigation system, iliac bone defects were created in beagle dogs as preoperatively planned on CAD, filled with HA implants shaped to fit the bone defect sites, and coated with a recombinant human bone morphogenetic protein (rhBMP)-2-containing dough bone-forming material. Postoperative CT revealed that the new bone was formed around the implant over time. Anatomical healthy bone repair was confirmed to be completed 12 weeks after the surgery. These results demonstrate potential novel technology for efficacious and accurate repair of large bone defects without bone grafting
Bayesian Approach to Find a Long-Term Trend in Erratic Polarization Variations Observed in Blazars
We developed a method to separate a long-term trend from observed temporal
variations of polarization in blazars using a Bayesian approach. The temporal
variation of the polarization vector is apparently erratic in most blazars,
while several objects occasionally exhibited systematic variations, for
example, an increase of the polarization degree associated with a flare of the
total flux. We assume that the observed polarization vector is a superposition
of distinct two components, a long-term trend and a short-term variation
component responsible for short flares. Our Bayesian model estimates the
long-term trend which satisfies the condition that the total flux correlates
with the polarized flux of the short-term component. We demonstrate that
assumed long-term polarization components are successfully separated by the
Bayesian model for artificial data. We applied this method to photopolarimetric
data of OJ 287, S5 0716+714, and S2 0109+224. Simple and systematic long-term
trends were obtained in OJ 287 and S2 0109+224, while no such a trend was
identified in S5 0716+714. We propose that the apparently erratic variations of
polarization in OJ 287 and S2 0109+224 are due to the presence of the long-term
polarization component. The behavior of polarization in S5 0716+714 during our
observation period implies the presence of a number of polarization components
having a quite short time-scale of variations.Comment: 12 pages, 7 figures, accepted for publication in PAS
Two cases of gastrointestinal perforation after radiotherapy in patients receiving tyrosine kinase inhibitor for advanced renal cell carcinoma
Spectropolarimetric Study on Circumstellar Structure of Microquasar LS I +61deg 303
We present optical linear spectropolarimetry of the microquasar LS I
+61 303. The continuum emission is mildly polarized (up to 1.3 %) and
shows almost no temporal change. We find a distinct change of polarization
across the H emission line, indicating the existence of polarization
component intrinsic to the microquasar. We estimate the interstellar
polarization (ISP) component from polarization of the H line and derive
the intrinsic polarization component. The wavelength dependence of the
intrinsic component is well explained by Thomson scattering in equatorial disk
of the Be-type mass donor. The position angle (PA) of the intrinsic
polarization represents the rotational axis of the Be disk.
This PA is nearly perpendicular to the PA of the radio jet found during
quiescent phases. Assuming an orthogonal disk-jet geometry around the compact
star, the rotational axis of the accretion disk is almost perpendicular to that
of the Be disk. Moreover, according to the orbital parameters of the
microquasar, the compact star is likely to get across the Be disk around their
periastron passage. We discuss the peculiar circumstellar structure of this
microquasar inferred from our observation and possible connection with its
high-energy activities.Comment: 17pages, 7figures; accepted for Publications of the Astronomical
Society of Japa
Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization
We report on the correlation between the flux, color and polarization
variations on time scales of days--months in blazars, and discuss their
universal aspects. We performed monitoring of 42 blazars in the optical and
near-infrared bands from 2008 to 2010 using TRISPEC attached to the "Kanata"
1.5-m telescope. We found that 28 blazars exhibited "bluer-when-brighter"
trends in their whole or a part of time-series data sets. This corresponds to
88% of objects that were observed for >10 days. Thus, our observation
unambiguously confirmed that the "bluer-when-brighter" trend is common in the
emission from blazar jets. This trend was apparently generated by a variation
component with a constant and relatively blue color and an underlying red
component. Prominent short-term flares on time scales of days--weeks tended to
exhibit a spectral hysteresis; their rising phases were bluer than their decay
phases around the flare maxima. In contrast to the strong flux--color
correlation, the correlation of the flux and polarization degree was relatively
weak; only 10 objects showed significant positive correlations. Rotations of
polarization were detected only in three objects: PKS 1510-089, 3C 454.3, and
PKS 1749+096, and possibly in S5 0716+714. We also investigated the dependence
of the degree of variability on the luminosity and the synchrotron peak
frequency, \nu_peak. As a result, we found that lower luminosity and higher
\nu_peak objects had smaller variations in their amplitudes both in the flux,
color, and polarization degree. Our observation suggests the presence of
several distinct emitting sources, which have different variation time-scales,
colors, and polarizations. We propose that the energy injection by, for
example, internal shocks in relativistic shells is a major factor for blazar
variations on time scales of both days and months.Comment: 39 pages, accepted for publication in PAS
The E-box DNA binding protein Sgc1p suppresses the gcr2 mutation, which is involved in transcriptional activation of glycolytic genes in Saccharomyces cerevisiae
AbstractGlycolytic gene expression is mediated by the Gcr1p-Gcr2p transcriptional activation complex. A screen for multicopy suppressors of gcr2 yielded SGC1. SGC1’s suppression activity was specific to gcr2, it did not extend to gcr1. Disruption of SGC1 moderately affected glycolytic enzyme activities, although no growth defect was evident. Sgc1p exhibits a bHLH motif which is characteristic of E-box DNA-binding proteins. DNA footprinting experiments demonstrated Sgc1p’s ability to bind at an E-box. However, its binding specificity was less than 10-fold, which is also characteristic of E-box binding proteins. LexA fusion experiments demonstrated that Sgc1p has weak intrinsic activating activity independent of GCR1 and GCR2. We propose that Sgc1p binds at E-boxes of glycolytic genes and contributes to their activation
Spiral Tissue Microarrays as Next Evolutionary Step in the High-density Tissue Microarray Technology
Tissue microarray (TMA) is a well-established technique that connects basic research with clinical applications that allow the validation of many pathobiologic events from gene expression dysregulation to genomic aberrations. However, conventional TMAs have several limitations such as limited representation of tissue heterogeneity, destruction of donor tissue blocks due to coring and usage of particular specimens that have limited evaluable material (tissue from thin specimens or needle biopsies). We have developed a novel method, which we termed "Spiral TMA" that generates TMAs that allow for improved representation of the donor tissue while keeping the architectural details of the donor block intact. This technology is ideal for specimens with limited tissue without the need to punch holes into the original block and therefore preserving the tissue integrity. In this report, we describe the methodology of constructing Spiral TMA and demonstrate the validation of tumor representation and tissue heterogeneity by comparing Spiral TMA to conventional TMA using immunohistochemical staining to EGFR and CK7
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