654 research outputs found
Salt Effects on Folding of a Helical Mini Protein Villin Headpiece Subdomain HP36 Studied by Generalized-Ensemble Simulations
Analysis of Speaker Adaptation Algorithms for HMM-based Speech Synthesis and a Constrained SMAPLR Adaptation Algorithm
In this paper we analyze the effects of several factors and configuration choices encountered during training and model construction when we want to obtain better and more stable adaptation in HMM-based speech synthesis. We then propose a new adaptation algorithm called constrained structural maximum a posteriori linear regression (CSMAPLR) whose derivation is based on the knowledge obtained in this analysis and on the results of comparing several conventional adaptation algorithms. Here we investigate six major aspects of the speaker adaptation: initial models transform functions, estimation criteria, and sensitivity of several linear regression adaptation algorithms algorithms. Analyzing the effect of the initial model, we compare speaker-dependent models, gender-independent models, and the simultaneous use of the gender-dependent models to single use of the gender-dependent models. Analyzing the effect of the transform functions, we compare the transform function for only mean vectors with that for mean vectors and covariance matrices. Analyzing the effect of the estimation criteria, we compare the ML criterion with a robust estimation criterion called structural MAP. We evaluate the sensitivity of several thresholds for the piecewise linear regression algorithms and take up methods combining MAP adaptation with the linear regression algorithms. We incorporate these adaptation algorithms into our speech synthesis system and present several subjective and objective evaluation results showing the utility and effectiveness of these algorithms in speaker adaptation for HMM-based speech synthesis
NMR studies of the incommensurate helical antiferromagnet EuCo2P2 : determination of the antiferromagnetic propagation vector
Recently Ding et al. [Phys. Rev. B 95, 184404 (2017)] reported that their
nuclear magnetic resonance (NMR) study on EuCoAs successfully
characterized the antiferromagnetic (AFM) propagation vector of the
incommensurate helix AFM state, showing that NMR is a unique tool for
determination of the spin structures in incommensurate helical AFMs. Motivated
by this work, we have carried out Eu, P and Co NMR
measurements on the helical antiferromagnet EuCoP with an AFM ordering
temperature = 66.5 K. An incommensurate helical AFM structure was
clearly confirmed by Eu and P NMR spectra on single crystalline
EuCoP in zero magnetic field at 1.6 K and its external magnetic field
dependence. Furthermore, based on Co NMR data in both the paramagnetic
and the incommensurate AFM states, we have determined the model-independent
value of the AFM propagation vector k = (0, 0, 0.73 0.09)2/ where
is the -axis lattice parameter. The temperature dependence of k is also
discussed.Comment: 8 pages, 10 figures, accepted for publication in Phys. Rev. B. arXiv
admin note: substantial text overlap with arXiv:1704.0629
Status of Acute Stroke Practice in Patients with a Cardiac Implantable Electronic Device
Although diagnostic and therapeutic strategies for acute stroke patients in Japan depend largely on magnetic resonance imaging (MRI), patients with cardiac implantable electronic devices (CIED) must still rely on com-puted tomography (CT). We retrospectively analyzed clinical and neuroimaging data of ischemic stroke patients with CIED treated at our hospital. Forty-five patients were enrolled in the study. Patients were divided into two groups according to whether corresponding lesions were detected (group A, n = 21) or not detected (group B, n = 24) by the first brain CT. We also evaluated in detail the clinical courses of patients who arrived at hospital within therapeutic time windows for recanalization therapy. Negative fresh infarct in the first CT was associated, though not significantly, with early onset-to-arrival time and subcortical white matter infarction. Five patients did not undergo recanalization therapy because their families did not agree to the procedure. The reasons for their lack of consent included inadequate information about the safety and efficacy of recanalization therapy because MRI could not be performed. Our study confirmed delayed detection of the corresponding lesion and undertreatment for acute stroke in patients with CIED
High-speed scanless entire bandwidth mid-infrared chemical imaging
Mid-infrared spectroscopy probes molecular vibrations to identify chemical
species and functional groups. Therefore, mid-infrared hyperspectral imaging is
one of the most powerful and promising candidates for chemical imaging using
optical methods. Yet high-speed and entire bandwidth mid-infrared hyperspectral
imaging has not been realized. Here we report a mid-infrared hyperspectral
chemical imaging technique that uses chirped pulse upconversion of sub-cycle
pulses at the image plane. This technique offers a lateral resolution of 15
m, and the field of view is adjustable between 800 m 600
m to 12 mm 9 mm. The hyperspectral imaging produces a 640
480 pixel image in 8 s, which covers a spectral range of 640-3015
cm, comprising 1069 wavelength points and offering a wavenumber
resolution of 2.6-3.7 cm. For discrete frequency mid-infrared imaging,
the measurement speed reaches a frame rate of 5 kHz, the repetition rate of the
laser. As a demonstration, we effectively identified and mapped different
components in a microfluidic device, plant cell, and mouse embryo section. The
great capacity and latent force of this technique in chemical imaging promise
to be applied to many fields such as chemical analysis, biology, and medicine.Comment: 22 pages, 10 figure
ALMA ACA detection of submillimeter emission associated with the west hot spot of the radio galaxy Pictor A
In order to investigate the far-infrared excess detected from the west hot
spot of the radio galaxy Pictor A with the Herschel observatory, a
submillimeter photometry is performed with the Atacama Compact Array (ACA) of
the Atacama Large Millimeter/submillimeter Array at Band 8 with the reference
frequency of 405 GHz. A submillimeter source is discovered at the radio peak of
the hot spot. Because the 405 GHz flux density of the source, mJy,
agrees with the extrapolation of the synchrotron radio spectrum, the
far-infrared excess is suggested to exhibit no major contribution at the ACA
band. In contrast, by subtracting the power-law spectrum tightly constrained by
the radio and ACA data, the significance of the excess in the Herschel band is
well confirmed. No diffuse submillimeter emission is detected within the ACA
field of view, and thus, the excess is ascribed to the west hot spot itself. In
comparison to the previous estimate based on the Herschel data, the relative
contribution of the far-infrared excess is reduced by a factor of .
The spectrum of the excess below the far-infrared band is determined to be
harder than that of the diffusive shock acceleration. This strengthens the
previous interpretation that the excess originates via the magnetic turbulence
in the substructures within the hot spot. The ACA data are utilized to evaluate
the magnetic field strength of the excess and of diffuse radio structure
associated to the hot spot.Comment: 10 pages,4 figures, 3 tables, accepted for Ap
Seasonal Fluctuation of Polycyclic Aromatic Hydrocarbons and Aerosol Genotoxicity in Long-Range Transported Air Mass Observed at the Western End of Japan
In order to clarify the level transboundary air pollution caused by polycyclic aromatic hydrocarbons (PAHs) and genotoxic substances, aerosols were collected from forest and suburban sites in Nagasaki, west Japan, for 6 years. The PAH concentration was measured, and the genotoxicity of the substances were evaluated using the umu test. The results showed no notable trends in the concentration or toxicity of either sites throughout the study period. The suburban and forest sites shared similar seasonal fluctuation patterns and quantitative values, suggesting that the western end of Japan might be affected by long-range transported pollutants, especially in winter. PAH concentration and genotoxicity showed the same seasonal patterns of increased levels in winter and lower levels in summer. This suggests that PAHs and genotoxic substances were correlated and share common sources. Back trajectory and source analyses were conducted using the diagnostic ratios of PAHs. It was predicted that air pollution by PAHs at the forest site arise predominantly as a result of biomass or coal combustion in continental regions, such as northern parts of China and the Korean Peninsula. This is particularly expected in winter. Therefore, genotoxic substances would also be strongly influenced by transboundary pollution from the continental region. In addition, it was estimated that the contribution of transboundary PAH pollution could reach 70% at the suburban site in winter
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