| 1071. |
- Nakajima, K., et al.
(författare)
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Diagnostic accuracy of an artificial neural network compared with statistical quantitation of myocardial perfusion images: a Japanese multicenter study
- 2017
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Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - : Springer Science and Business Media LLC. - 1619-7070 .- 1619-7089. ; 44:13, s. 2280-2289
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Artificial neural networks (ANN) might help to diagnose coronary artery disease. This study aimed to determine whether the diagnostic accuracy of an ANN-based diagnostic system and conventional quantitation are comparable. Methods The ANN was trained to classify potentially abnormal areas as true or false based on the nuclear cardiology expert interpretation of 1001 gated stress/rest Tc-99m-MIBI images at 12 hospitals. The diagnostic accuracy of the ANN was compared with 364 expert interpretations that served as the gold standard of abnormality for the validation study. Conventional summed stress/rest/difference scores (SSS/SRS/SDS) were calculated and compared with receiver operating characteristics (ROC) analysis. Results The ANN generated a better area under the ROC curves (AUC) than SSS (0.92 vs. 0.82, p < 0.0001), indicating better identification of stress defects. The ANN also generated a better AUC than SDS (0.90 vs. 0.75, p < 0.0001) for stress-induced ischemia. The AUC for patients with old myocardial infarction based on rest defects was 0.97 (0.91 for SRS, p = 0.0061), and that for patients with and without a history of revascularization based on stress defects was 0.94 and 0.90 (p = 0.0055 and p < 0.0001 vs. SSS, respectively). The SSS/SRS/SDS steeply increased when ANN values (probability of abnormality) were > 0.80. Conclusion The ANN was diagnostically accurate in various clinical settings, including that of patients with previous myocardial infarction and coronary revascularization. The ANN could help to diagnose coronary artery disease.
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| 1072. |
- Nguyen, T. S., et al.
(författare)
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Hydro-mechanical response of a fractured granitic rock mass to excavation of a test pit - the Kamaishi Mine experiment in Japan
- 2001
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Ingår i: International Journal of Rock Mechanics And Mining Sciences. - 1365-1609 .- 1873-4545. ; 38:1, s. 79-94
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Tidskriftsartikel (refereegranskat)abstract
- A thermo-hydro-mechanical experiment was conducted in a fractured granitic ruck mass at the Kamaishi Mine in Japan. The experiment consists of the excavation of a cylindrical test pit on the floor of an experimental drift. The test pit was then lilted with bentonite with an embedded heater. During the excavation of the test pit, the hydromechanical response of the surrounding rock was monitored. This paper presents the efforts of four research teams to numerically simulate the hydro-mechanical response of the rock mass during excavation. While the total inflow rate to the test pit, the flow distribution on the pit walls and the displacements in the rock mass away From the pit could be reasonably predicted, the pore pressure in individual boreholes, and the expansion behaviour of the pit were less successfully simulated. The reasons for these discrepancies are discussed in the paper.
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| 1073. |
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| 1074. |
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| 1075. |
- Noutsos, A., et al.
(författare)
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Radio and γ-ray constraints on the emission geometry and birthplace of PSR j2043+2740
- 2011
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 728:2, s. 77-
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Tidskriftsartikel (refereegranskat)abstract
- We report on the first year of Fermi γ-ray observations of pulsed high-energy emission from the old PSR J2043 + 2740. The study of the γ-ray efficiency of such old pulsars gives us an insight into the evolution of pulsars' ability to emit in γ rays as they age. The y-ray light curve of this pulsar above 0.1 GeV is clearly defined by two sharp peaks, 0.353 ± 0.035 periods apart. We have combined the γ-ray profile characteristics of PSR J2043 + 2740 with the geometrical properties of the pulsar's radio emission, derived from radio-polarization data, and constrained the pulsar-beam geometry in the framework of a two-pole caustic (TPC) and an outer gap (OG) model. The ranges of magnetic inclination and viewing angle were determined to be {α, ζ} ∼ {52°-57°, 61°-68°} for the TPC model, and {α, ζ} ∼ {62°-73°, 74°-81°} and {α, ζ,} ∼ {72°-83°, 60°-75°} for the OG model. Based on this geometry, we assess possible birth locations for this pulsar and derive a likely proper motion, sufficiently high to be measurable with VLBI. At a characteristic age of 1.2 Myr, PSR J2043 + 2740 is the third oldest of all discovered, non-recycled, γ-ray pulsars: it is twice as old as the next oldest, PSR J0357 + 32, and younger only than the recently discovered PSR J1836 + 5925 and PSR J2055 + 25, both of which are at least five and ten times less energetic, respectively.
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| 1076. |
- Okada, S, et al.
(författare)
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Crystal growth and some properties of LuB4, LuAlB4, and Lu2AlB6
- 1996
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Ingår i: JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS. - : JAPAN J APPLIED PHYSICS. ; 35:9A
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Crystals of LuB4, LuAlB4, and Lu2AlB6 were grown by the high-temperature aluminium solution method using lutetium oxide and crystalline boron powders as starting materials. The growth conditions for obtaining single crystals of relatively large size were
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| 1077. |
- Okada, S, et al.
(författare)
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Synthesis and investigation of large crystals of (Cr1-xTMx)(3)B-4 with TM = Ti, V, Nb, Ta, Mo, and W
- 2000
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Ingår i: JOURNAL OF SOLID STATE CHEMISTRY. - : ACADEMIC PRESS INC. - 0022-4596. ; 154:1, s. 45-48
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Tidskriftsartikel (refereegranskat)abstract
- Single crystals of the ternary borides (Cr1-xTMx)(3)B-4 (TM = Ti, V, Nh, Ta, Mo, W) were grown by the flux method using molten aluminum as a solvent, The substances were subjected to chemical analyses and measurements of the unit cell parameters. Crystals
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| 1078. |
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| 1079. |
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| 1080. |
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