The AKARI far-infrared all-sky survey maps Doi, Yasuo; Takita, Satoshi; Ootsubo, Takafumi ...
Publications of the Astronomical Society of Japan,
06/2015, Letnik:
67, Številka:
3
Journal Article
Recenzirano
Odprti dostop
We present a far-infrared all-sky atlas from a sensitive all-sky survey using the Japanese AKARI satellite. The survey covers > 99% of the sky in four photometric bands centred at 65 μm, 90 μm, 140 ...μm, and 160 μm, with spatial resolutions ranging from 1′ to 1
${^{\prime\prime}_{.}}$
5. These data provide crucial information on the investigation and characterisation of the properties of dusty material in the interstellar medium (ISM), since a significant portion of its energy is emitted between ∼ 50 and 200 μm. The large-scale distribution of interstellar clouds, their thermal dust temperatures, and their column densities can be investigated with the improved spatial resolution compared to earlier all-sky survey observations. In addition to the point source distribution, the large-scale distribution of ISM cirrus emission, and its filamentary structure, are well traced. We have made the first public release of the full-sky data to provide a legacy data set for use in the astronomical community.
Background
Endovascular therapy has been shown to be effective in patients with acute cerebral large‐vessel occlusion, but real‐world efficacies are unknown.
Methods and Results
We conducted a ...prospective registry at 46 centers between October 2014 and January 2017. Eligible patients were those who were aged 20 years or older, with acute cerebral large‐vessel occlusion, and who were hospitalized within 24 hours of the onset. We enrolled both consecutive patients who were treated with or without endovascular therapy. Endovascular therapy included thrombectomy, balloon angioplasty, stenting, local fibrinolysis, and piercing. The primary outcome was a favorable outcome as defined by a modified Rankin Scale of 0 to 2 at 90 days after onset. Secondary outcomes were modified Rankin Scale of 0 to 1 and mortality. Safety outcomes were intracerebral hemorrhage or a recurrence of ischemic stroke. We constructed the 2242 (1121 each) propensity score–matched patients cohort based on a propensity score for endovascular therapy and estimated the adjusted odds ratio, followed by sensitivity analyses on original 2399 (1278 in endovascular therapy versus 1121 in no endovascular therapy) patients. In the propensity score–matched cohort, favorable outcomes were observed in 35.3% and 30.7% of patients in the endovascular therapy and no endovascular therapy groups, respectively (P=0.02). The adjusted odds ratio for the favorable outcome was 1.44 (95% confidence interval, 1.10–1.86, P=0.007). The efficacy of endovascular therapy in achieving favorable outcomes did not differ between our subgroups and in the sensitivity analyses.
Conclusions
Endovascular therapy decreased disabilities at 90 days in real‐world patients with acute cerebral large‐vessel occlusion.
Clinical Trial Registration
URL: http://www.clinicaltrials.gov. Unique identifier: NCT02419794.
We present high spatial resolution super(12)CO (J = 1-0) images taken by the Nobeyama 45 m telescope toward a 48' x 48' area, including the L1641-N cluster. The effective spatial resolution of the ...maps is 21", corresponding to 0.04 pc at a distance of 400 pc. A recent 1.1 mm dust continuum map reveals that the dense gas is concentrated in several thin filaments. We find that a few dust filaments are located at the parts where super(12)CO (J = 1-0) emission drops sharply. Furthermore, the filaments have two components with different velocities. The velocity difference between the two components is about 3 km s super(-1), corresponding to a Mach number of 10, significantly larger than the local turbulent velocity in the cloud. These facts imply that the collision of the two components (hereafter, the cloud-cloud collision) possibly contributed to the formation of these filaments. Since the two components appear to overlap toward the filaments on the plane of the sky, the collision may have occurred almost along the line of sight. Star formation in the L1641-N cluster was probably triggered by such a collision. We also find several parsec-scale CO shells whose centers are close to either the L1641-N cluster or the V 380 Ori cluster. We propose that these shells were created by multiple winds and/or outflows from cluster young stellar objects, i.e., "protocluster winds." One exceptional dust filament located at the western cloud edge lies along a shell; it is presumably part of the expanding shell. Both the cloud-cloud collision and protocluster winds are likely to influence the cloud structure and kinematics in this region.
We present an initial analysis of the properties of an all-sky image obtained by the Far-Infrared Surveyor (FIS) onboard the AKARI satellite, at 65 μm (N60), 90 μm (WIDE-S), 140 μm (WIDE-L), and 160 ...μm (N160). An absolute flux calibration was determined by comparing the data with COBE/DIRBE data sets; the intensity range was as wide as from a few MJy sr−1 to > 1 GJy sr−1. The uncertainties are considered to be the standard deviations with respect to the DIRBE data, and are less than 10% for intensities above 10, 3, 25, and 26 MJy sr−1 at the N60, WIDE-S, WIDE-L, and N160 bands, respectively. The characteristics of point sources in the image were also determined by stacking maps centred on photometric standard stars. The full width at half maxima of the point spread functions (PSFs) were 63″, 78″, and 88″ at the N60, WIDE-S, and WIDE-L bands, respectively. The PSF at the N160 band was not obtained due to the sensitivity, but it is thought to be the same as that of the WIDE-L one.
We have developed a spectral line On-The-Fly (OTF) observing mode for the Nobeyama Radio Observatory 45-m and the Atacama Submillimeter Telescope Experiment 10-m telescopes. Sets of digital ...autocorrelation spectrometers are available for OTF with heterodyne receivers mounted on the telescopes, including the focal-plane 5
$\times$
5 array receiver, BEARS, on the 45-m. During OTF observations, the antenna is continuously driven to cover the mapped region rapidly, resulting in a high observing efficiency and accuracy. Pointing of the antenna and readouts from the spectrometer are recorded as fast as 0.1s. In this paper we report on improvements made to the software and instruments, requirements and optimization of observing parameters, the data-reduction process, and verification of the system. It is confirmed that, using optimal parameters, the OTF is about twice as efficient as the conventional position-switch observing method.
•Low grade glioma that shows hyper intense area on T2 weighted MRI or FLAIR imaging.•MET-PET reflects the extent of glioma cell invasion, but does not coincide with MRI.•The pathological ...heterogeneity may reflect the images discrepancy of MET-PET and MRI.•The understanding of this relevance is useful for correct diagnosis and surgical planning.
The objective of the study was to investigate the correlation between differences between imaging modalities and histological heterogeneity in minimally enhancing glioma.
A prospective study was performed in 11 patients with minimally enhancing glioma (<1 cm3 volume) in the T2 or FLAIR hyperintense (T2/FL+) area who simultaneously underwent 11C-methionine (MET)-PET, and had a volume-based discrepancy between the T2/FL+ area and MET accumulation (MET+) area (tumor to normal cortex (T/N) ratio ≥1.3) of >10%. The correlation between the imaging discrepancy and histological heterogeneity was investigated.
The average T/N ratio for the T2/FL+/MET+ area in grade II glioma (2.08 ± 0.4) was smaller than that in grade III (4.19 ± 2.4), whereas that for the T2/FL+/MET− area was similar in grade II (1.07 ± 0.2) and III (1.07 ± 0.1). The average T/N ratio for the T2/FL+/MET+ area in grade II and III was higher than that for the T2/FL+/MET− area (p < 0.0005 for grade II, p < 0.05 for grade III). In the T2/FL+/MET− area, 8 cases showed no neoplastic features, while the other 3 cases had neoplastic features with comparatively lower grade than the T2/FL+/MET+ area. The volumetric ratio of the MET+ area (16.8 ± 16.0 cm3) to the T2/FL+ area (41.5 ± 20.9 cm3) was 43.4%, and the volumetric difference in grade II cases (61.6%) tended to larger than that in grade III (50.6%). In immunohistochemical findings, the only MIB1 labeling index differed between grade II (5.5 ± 2.1) and III (23.2 ± 18.0) with significantly difference. In the T2/FL+/MET− area, 3 of 6 grade II gliomas had neoplastic features, whereas all 5 grade III gliomas had normal brain including one gliosis histologically.
The discrepancy between the T2/FL+ and MET+ areas could reflect spatial heterogeneity in histological findings. An understanding of the correlation between imaging and pathology based on spatial heterogeneity may assist with appropriate diagnosis and treatment for patients with glioma.
We present the results of C{sup 18}O(J = 1-0) mapping observations of a 20' x 18' area in the Lynds 1204 molecular cloud associated with the Sharpless 2-140 (S140) H II region. The C{sup 18}O cube ...({alpha}-{delta}-v{sub LSR}) data show that there are three clumps of sizes {approx}1 pc in the region. Two of these have peculiar redshifted velocity components at their edges, which can be interpreted as the results of the interaction between the cloud and the Cepheus Bubble. From the C{sup 18}O cube data, clumpfind identified 123 C{sup 18}O cores, which have mean radius, velocity width in FWHM, and LTE mass of 0.36 {+-} 0.07 pc, 0.37 {+-} 0.09 km s{sup -1}, and 41 {+-} 29 M{sub sun}, respectively. Considering the uncertainty in the C{sup 18}O abundance, all the cores in S140 are most likely to be gravitationally bound. We derived a C{sup 18}O core mass function (CMF), which shows a power-law-like behavior above a turnover at 30 M{sub sun}. The best-fit power-law index of -2.1 {+-} 0.2 is quite consistent with that of the initial mass function (IMF) and the C{sup 18}O CMF in the OMC-1 region as found by Ikeda and Kitamura. Kramer et al. estimated the power-law index of -1.65 in S140 from the C{sup 18}O(J = 2-1) data, which is inconsistent with this study. The C{sup 18}O(J = 2-1) data are spatially limited to the central part of the cloud and are likely to be biased toward high-mass cores, leading to the flatter CMF. Consequently, this study and our previous study strongly support that the power-law form of the IMF has already been determined at the density of {approx}< 10{sup 3}-10{sup 4} cm{sup -3}, traced by the C{sup 18}O(J = 1-0) line.
Endovascular therapy (EVT) is strongly recommended for acute cerebral large vessel occlusion with the Alberta Stroke Program Early CT Score (ASPECTS) ≥6 due to occlusion of the internal carotid ...artery or M1 segment of the middle cerebral artery. However, the effect of EVT for patients who have ischemic core with ASPECTS ≤5 (0–5) was not established. The purpose of this study was to elucidate the outcomes of EVT for patients with large ischemic core.
Based on the data of The Recovery by Endovascular Salvage for Cerebral Ultra-Acute Embolism Japan Registry 2, patients with internal carotid artery or M1 segment of the middle cerebral artery occlusion and pretreatment ASPECTS 0 to 5 on noncontrast CT or diffusion-weighted image were extracted, and the outcomes by EVT were analyzed. Primary end point was defined as a good functional outcome (modified Rankin Scale score of ≤2) after 90 days.
Among 2420 registered patients, 504 patients were with internal carotid artery or M1 segment of the middle cerebral artery occlusion and ASPECTS 0 to 5. Among these 504 patients, 172 (34.1 %) were treated with EVT (EVT group) and 332 (65.9 %) without (no-EVT group). In the no-EVT group, elderly patients, females, poor prestroke modified
Rankin Scale, high National Institutes of Health Stroke Scale, low ASPECTS, and late admission were significantly more observed. Good functional outcomes were significantly more observed in the EVT group than in the no-EVT group (19.8 % versus 4.2 %; P<0.0001; adjusted odds ratio, 2.33; 95% CI, 1.10–4.94). The incidences of symptomatic intracranial hemorrhage within 72 hours did not significantly different between the EVT group and the no-EVT group (3.7 % versus 4.9%; P=0.55; adjusted odds ratio, 0.50; 95% CI, 0.14–1.73).
Although outcomes in this group of patients were usually poor, the data suggested EVT may increase the likelihood of a good functional outcome.
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