83 research outputs found

    “Open-Loop” Tracking Interferometer Measurement Using Rotary Axes of a Five-Axis Machine Tool

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    The tracking interferometer, or the laser tracker, is a laser interferometer with a steering mechanism to change the laser beam direction to automatically follow a retroreflector. Many researchers have studied its application to the multilateration to measure the retroreflector's three-dimensional position. This paper shows that the multilateration measurement can be done by regulating the laser beam toward the command retroreflector position, assuming that the machine tool's positioning error is reasonably small. The machine's rotary axes are used to regulate the laser beam direction. The proposed scheme enables a user to perform the multilateration measurement by using a laser interferometer and the machine's rotary axes only, without requiring any specialized tracking mechanism. An experiment is presented to investigate its measurement performance. The paper's emphasis is on the assessment of its measurement uncertainty, introduced by the elimination of automated tracking mechanism

    Kinematic modeling and error sensitivity analysis for on-machine five-axis laser scanning measurement under machine geometric errors and workpiece setup errors

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    On-machine scanning measurement of workpiece geometry has a strong advantage in its efficiency, compared to conventional discrete measurement using a touch-trigger probe. When a workpiece is rotated and tilted, position and orientation errors of the workpiece with respect to the machine’s rotary axes can be a significant contributor to the measurement error. Rotary axis geometric errors also influence the measurement error. To establish the traceability of on-machine measurement with workpiece rotation, this paper kinematically formulates their contribution to measured profiles. As a practical application example, this paper presents the measurement error assessment for an axis-symmetric part. Based on the present kinematic model, this paper compares error contributors to the cases (1) where an axis-symmetric part is placed concentric to the rotary axis, and (2) where it is placed away from the rotary axis

    Two Cases of Nivolumab Re-Administration after Pneumonitis as Immune-Related Adverse Events

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    Nivolumab is a recently approved medication for the treatment of unresectable malignant melanoma. Many immune-related adverse events (irAEs) associated with nivolumab have been reported, such as pneumonitis, hepatitis, dermatitis, and thyroiditis. Prednisolone can effectively treat irAEs. However, it is unclear how or if nivolumab should be administered to patients after they have experienced an irAE. Herein, we show 2 patients who underwent pneumonitis as irAE. Case 1 demonstrated a cryptogenic organizing pneumonia pattern in the CT scan and case 2 had a diffuse alveolar damage (DAD) pattern. Oral corticosteroids improved chest shadow of CT scan in both cases. However, when nivolumab was re-administrated, case 1 demonstrated no symptoms, but case 2 demonstrated pneumonia again. From our cases, it is difficult to re-administrate nivolumab for the patients with pneumonitis which shows a DAD pattern in CT, even if oral corticosteroids improve their symptoms

    Annexin A2-STAT3-Oncostatin M receptor axis drives phenotypic and mesenchymal changes in glioblastoma

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    Glioblastoma (GBM) is characterized by extensive tumor cell invasion, angiogenesis, and proliferation. We previously established subclones of GBM cells with distinct invasive phenotypes and identified annexin A2 (ANXA2) as an activator of angiogenesis and perivascular invasion. Here, we further explored the role of ANXA2 in regulating phenotypic transition in GBM. We identified oncostatin M receptor (OSMR) as a key ANXA2 target gene in GBM utilizing microarray analysis and hierarchical clustering analysis of the Ivy Glioblastoma Atlas Project and The Cancer Genome Atlas datasets. Overexpression of ANXA2 in GBM cells increased the expression of OSMR and phosphorylated signal transducer and activator of transcription 3 (STAT3) and enhanced cell invasion, angiogenesis, proliferation, and mesenchymal transition. Silencing of OSMR reversed the ANXA2-induced phenotype, and STAT3 knockdown reduced OSMR protein expression. Exposure of GBM cells to hypoxic conditions activated the ANXA2-STAT3-OSMR signaling axis. Mice bearing ANXA2-overexpressing GBM exhibited shorter survival times compared with control tumor-bearing mice, whereas OSMR knockdown increased the survival time and diminished ANXA2-mediated tumor invasion, angiogenesis, and growth. Further, we uncovered a significant relationship between ANXA2 and OSMR expression in clinical GBM specimens, and demonstrated their correlation with tumor histopathology and patient prognosis. Our results indicate that the ANXA2-STAT3-OSMR axis regulates malignant phenotypic changes and mesenchymal transition in GBM, suggesting that this axis is a promising therapeutic target to treat GBM aggressiveness

    Preoperative Biliary Drainage in Cases of Borderline Resectable Pancreatic Cancer Treated with Neoadjuvant Chemotherapy and Surgery

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    Objective. To elucidate the optimum preoperative biliary drainage method for patients with pancreatic cancer treated with neoadjuvant chemotherapy (NAC). Material and Methods. From January 2010 through December 2014, 20 patients with borderline resectable pancreatic cancer underwent preoperative biliary drainage and NAC with a plastic or metallic stent and received NAC at Hiroshima University Hospital. We retrospectively analyzed delayed NAC and complication rates due to biliary drainage, effect of stent type on perioperative factors, and hospitalization costs from diagnosis to surgery. Results. There were 11 cases of preoperative biliary drainage with plastic stents and nine metallic stents. The median age was 64.5 years; delayed NAC occurred in 9 cases with plastic stent and 1 case with metallic stent (p=0.01). The complication rates due to biliary drainage were 0% (0/9) with metallic stents and 72.7% (8/11) with plastic stents (p=0.01). Cumulative rates of complications determined with the Kaplan-Meier method on day 90 were 60% with plastic stents and 0% with metallic stents (log-rank test, p=0.012). There were no significant differences between group in perioperative factors or hospitalization costs from diagnosis to surgery. Conclusions. Metallic stent implantation may be effective for preoperative biliary drainage for pancreatic cancer treated with NAC

    Transabdominal Ultrasound Real-time Tissue Elastography as a Screening Method for Early Chronic Pancreatitis

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    Background and Purpose: The concept of early chronic pancreatitis was proposed in Japan with the aim to improve the prognosis of patients with chronic pancreatitis. Endoscopic ultrasonography plays an important role in early diagnoses, but is limited by its invasiveness and poor objectivity. Hence, this study aimed to determine the usefulness of transabdominal ultrasound real-time tissue elastography as a screening method for early chronic pancreatitis. Methods: We retrospectively examined 73 patients who underwent simultaneous ultrasound real-time tissue elastography and endoscopic ultrasonography from 2011 to 2014. The correlation between feature values (MEAN, %AREA, COMP) calculated by real-time tissue elastography and the Rosemont classification of endoscopic ultrasonography diagnostic criteria for chronic pancreatitis, and the diagnostic ability of ultrasound real-time tissue elastography to recognize “indeterminate for chronic pancreatitis” findings, which correspond to early chronic pancreatitis, were evaluated. Main Results: Based on the Rosemont classification, 26 patients were “normal”, 16 were “indeterminate for chronic pancreatitis”, 13 were “suggestive of chronic pancreatitis”, and 18 were “consistent with chronic ancreatitis”. There were significant correlations between the feature values (MEAN, %AREA, COMP) and the Rosemont classification (p < 0.001; ρ = –0.788, 0.779, and 0.489, respectively). The area under the curve for the ability of MEAN to diagnose “indeterminate for chronic pancreatitis” was 0.889 (sensitivity, 93.8%; specificity, 76.9%). Conclusions: The feature values calculated by ultrasound real-time tissue elastography were correlated with the Rosemont classification. Ultrasound real-time tissue elastography may be a useful screening method for early chronic pancreatitis

    The ASTRO-H X-ray Observatory

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    The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the high-energy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-throughput spectrometer sensitive over 0.3-2 keV with high spectral resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5-80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40-600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray

    The Quiescent Intracluster Medium in the Core of the Perseus Cluster

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    Clusters of galaxies are the most massive gravitationally-bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and a host of astrophysical processes. Knowledge of the dynamics of the pervasive hot gas, which dominates in mass over stars in a cluster, is a crucial missing ingredient. It can enable new insights into mechanical energy injection by the central supermassive black hole and the use of hydrostatic equilibrium for the determination of cluster masses. X-rays from the core of the Perseus cluster are emitted by the 50 million K diffuse hot plasma filling its gravitational potential well. The Active Galactic Nucleus of the central galaxy NGC1275 is pumping jetted energy into the surrounding intracluster medium, creating buoyant bubbles filled with relativistic plasma. These likely induce motions in the intracluster medium and heat the inner gas preventing runaway radiative cooling; a process known as Active Galactic Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus cluster core, which reveal a remarkably quiescent atmosphere where the gas has a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s is found across the 60 kpc image of the cluster core. Turbulent pressure support in the gas is 4% or less of the thermodynamic pressure, with large scale shear at most doubling that estimate. We infer that total cluster masses determined from hydrostatic equilibrium in the central regions need little correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July
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