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

Morphometric human embryonic brain features according to developmental stage

Objectives: The present study investigated linear, area, and volume measurements of human brain samples according to Carnegie stages (CS) in an attempt to select suitable morphometric features that reflect embryonic development. Methods: Using magnetic resonance imaging, we measured seven linear segments, three separate areas, and three regional volumes in 101 samples between CS13 and 23. Brain volume was determined via manual segmentation of the magnetic resonance image, whereby a formula was generated to estimate the volume of each linear measurement. Results: All parameters correlated with crown-rump length. Bitemporal length and mesencephalic height increased linearly according to the CS, and a high correlation between bitemporal length and both whole-brain (r=0.98) and prosencephalon (r=0.99) volumes was found when brain cavity volume was excluded. Conclusion: Morphometric data related to human embryonic stages are valuable for correcting and comparing sonographic data. The present approach may contribute to improvements in prenatal diagnostics by enabling the selection of more suitable measurements during early embryonic stages

Two-dimensional beam emission spectroscopy for hydrogen isotope negative neutral beam in Large Helical Device

A new beam emission spectroscopy system that has improved lines of sight is installed in the Large Helical Device (LHD), and routine measurement has been started in the 21st LHD experiment campaign in 2019–2020. The new system is optimized for hydrogen isotope experiments by equipping a rotatable large-diameter interference filter to be compatible with either the hydrogen or the deuterium beam emission component. An avalanche photo diode detector array having 8 × 8 pixels is used for obtaining a radial–vertical image of electron density fluctuation covering the mid-radius to the plasma periphery. Spatial resolution and wavenumber cutoff are derived from equilibrium reconstruction and plasma kinetic profiles. Obtained fluctuation data is presented for a low field high beta discharge. The spatiotemporal structure of the fluctuations is clearly shown by Fourier correlation analyses

Bifurcation physics of magnetic islands and stochasticity explored by heat pulse propagation studies in toroidal plasmas

Bifurcation physics of a magnetic island was investigated using the heat pulse propagation technique produced by the modulation of electron cyclotron heating. There are two types of bifurcation phenomena observed in a large helical device (LHD) and DIII-D. One is a bifurcation of the magnetic topology between nested and stochastic fields. The nested state is characterized by the bi-directional (inward and outward) propagation of the heat pulse with slow propagation speed. The stochastic state is characterized by the fast propagation of the heat pulse with electron temperature flattening. The other bifurcation is between the magnetic island with larger thermal diffusivity and that with smaller thermal diffusivity. The damping of toroidal flow is observed at the O-point of the magnetic island both in helical plasmas and in tokamak plasmas during a mode locking phase with strong flow shears at the boundary of the magnetic island. Associated with the stochastization of the magnetic field, the abrupt damping of toroidal flow is observed in LHD. The toroidal flow shear shows a linear decay, while the ion temperature gradient shows an exponential decay. This observation suggests that this flow damping is due to the change in the non-diffusive term of momentum transport

Diagnostic Ureteroscopy for Cases Clinically Suspected of Carcinoma in Situ of the Upper Urinary Tract

　We elucidate the fate of cases clinically suspected of carcinoma in situ (Cis) of the upper tract with serial ureteroscopy. Of 143 patients who underwent ureteroscopy for suspected upper tract urothelial carcinoma (UTUC) between January 2008 and February 2016, 12 cases with consistently positive urine cytology and poorly detectable upper-tract malignancies by imaging were reviewed. In these 12 patients, 19 ureteroscopy procedures (25 renal units) were performed. Vesical random biopsy was performed before the 1st ureteroscopy to exclude malignancy of the bladder in all 12 cases. Median follow-up was 42 (13-67) months. Positive biopsy results at the 1st ureteroscopy were obtained in 3 (25%) patients and all were diagnosed wth Cis of the upper tract. Two (17%) of 9 patients who were negative or inconclusive at the 1st ureteroscopy were finally diagnosed as UTUC, but plural ureteroscopy procedures were needed for the diagnoses in both. Carcinoma of the bladder appeared in 5 (42%) patients during follow-up, despite the earlier ruling out of vesical malignancy. Four (33%) of those 5 patients never developed upper-tract urothelial carcinoma during follow-up. Caution is required before undertaking radical surgery for cases clinically suspected of Cis of the upper tract. In our experience, only 42% of such patients developed UTUC; another 33% eventually developed carcinoma of the bladder without UTUC

Color-taste correspondence tested by the Stroop task

People consistently associate colors with tastes (e.g., pink-sweet, yellow-sour). However, little has been known on the strength of those color-taste correspondences. The current study examined the congruency effect of color-taste correspondence using two Stroop word categorization tasks. The visual stimuli consisted of food names associated with sweet and sour tastes, presented in different shades of pink and yellow font colors. Participants were instructed to categorize the taste (sweet or sour) of the words in the Stroop word-taste categorization task and to discriminate the font color (pink or yellow) of the words in the Stroop word-color discrimination task. Results showed that participants responded faster in congruent conditions (sweet-pink and sour-yellow) than incongruent conditions (sweet-yellow and sour-pink) in both tasks. Specifically, yellow font colors facilitated the categorization of sour taste words compared to pink font colors, whereas sweet taste words facilitated the discrimination of pink font colors compared to sour taste words. These results provide further evidence for the congruency effect of color-taste correspondence in facilitating the processing of taste-related words and colors. Furthermore, the congruency effect was shown to operate bidirectionally, influencing both the conceptual meaning of tastes and perceptual color perception. This study highlights the significant interference effect of color-taste correspondence on cognitive processing as assessed by the Stroop task

Factors Predicting Adhesion between Renal Capsule and Perinephric Adipose Tissue in Partial Nephrectomy

In minimally invasive partial nephrectomy (MIPN), it is important to preoperatively predict the degree of difficulty of tumor resection. When severe adhesions occur between the renal capsule and perinephric adipose tissue, detachment can be difficult. Preoperative prediction of adhesion is thought to be useful in the selection of surgical procedure. Subjects were 63 patients of a single surgeon who had received MIPN between April 2008 and August 2013 at Okayama University Hospital. Of these patients, this study followed 47 in whom the presence or absence of adhesions between the renal capsule and perinephric adipose tissue was confirmed using intraoperative videos. Data collected included: sex, BMI, CT finding (presence of fibroids in perinephric adipose tissue), comorbidities and lifestyle. Adhesion was observed in 7 patients (14.9%). The mean operative time was 291.6min in the adhesion group, and 226.3min in the group without. The increased time in the adhesions group was significant (p＜0.05). Predictive factors were a positive CT finding for fibroid structure and comorbidity of hypertension (p＜0.05). In MIPN, difficulty of surgery can be affected by the presence of adhesion of the perinephric adipose tissue. Predicting such adhesion from preoperative CT is thus important