62 research outputs found
Considerations in hiPSC-derived cartilage for articular cartilage repair
Background: A lack of cell or tissue sources hampers regenerative medicine for articular cartilage damage.
Main text: We review and discuss the possible use of pluripotent stem cells as a new source for future clinical use. Human induced pluripotent stem cells (hiPSCs) have several advantages over human embryonic stem cells (hESCs). Methods for the generation of chondrocytes and cartilage from hiPSCs have been developed. To reduce the cost of this regenerative medicine, allogeneic transplantation is preferable. hiPSC-derived cartilage shows low immunogenicity like native cartilage, because the cartilage is avascular and chondrocytes are segregated by the extracellular matrix. In addition, we consider our experience with the aberrant deposition of lipofuscin or melanin on cartilage during the chondrogenic differentiation of hiPSCs.
Short conclusion: Cartilage generated from allogeneic hiPSC-derived cartilage can be used to repair articular cartilage damage
On-line Identification of Electro-Conductivity in Electrolytic Solutions
An on-line method is proposed to identify electro-conductivity in electrolytic solutions. The method uses a model of a cell of electrolytic solutions in a micro reactor modeled by an electronic circuit. The circuit consists of a cell part with a resister and a capacitor connected in series and a measurement part having a resister. Then the resistance and the capacitance of the cell part are identified to calculate the electro-conductivity. The identification scheme is the least-square method with a forgetting factor calculated on-line. To avoid the effect of differentiation of measured signals, a filter is added to the identification method. The effectiveness of the proposed control scheme is shown by numerical simulation.</p
Virtuoso: Massive Multilingual Speech-Text Joint Semi-Supervised Learning for Text-To-Speech
This paper proposes Virtuoso, a massively multilingual speech-text joint
semi-supervised learning framework for text-to-speech synthesis (TTS) models.
Existing multilingual TTS typically supports tens of languages, which are a
small fraction of the thousands of languages in the world. One difficulty to
scale multilingual TTS to hundreds of languages is collecting high-quality
speech-text paired data in low-resource languages. This study extends Maestro,
a speech-text joint pretraining framework for automatic speech recognition
(ASR), to speech generation tasks. To train a TTS model from various types of
speech and text data, different training schemes are designed to handle
supervised (paired TTS and ASR data) and unsupervised (untranscribed speech and
unspoken text) datasets. Experimental evaluation shows that 1) multilingual TTS
models trained on Virtuoso can achieve significantly better naturalness and
intelligibility than baseline ones in seen languages, and 2) they can
synthesize reasonably intelligible and naturally sounding speech for unseen
languages where no high-quality paired TTS data is available.Comment: Submitted to ICASSP 202
Miipher: A Robust Speech Restoration Model Integrating Self-Supervised Speech and Text Representations
Speech restoration (SR) is a task of converting degraded speech signals into
high-quality ones. In this study, we propose a robust SR model called Miipher,
and apply Miipher to a new SR application: increasing the amount of
high-quality training data for speech generation by converting speech samples
collected from the Web to studio-quality. To make our SR model robust against
various degradation, we use (i) a speech representation extracted from w2v-BERT
for the input feature, and (ii) a text representation extracted from
transcripts via PnG-BERT as a linguistic conditioning feature. Experiments show
that Miipher (i) is robust against various audio degradation and (ii) enable us
to train a high-quality text-to-speech (TTS) model from restored speech samples
collected from the Web. Audio samples are available at our demo page:
google.github.io/df-conformer/miipher/Comment: Accepted to WASPAA 202
LibriTTS-R: A Restored Multi-Speaker Text-to-Speech Corpus
This paper introduces a new speech dataset called ``LibriTTS-R'' designed for
text-to-speech (TTS) use. It is derived by applying speech restoration to the
LibriTTS corpus, which consists of 585 hours of speech data at 24 kHz sampling
rate from 2,456 speakers and the corresponding texts. The constituent samples
of LibriTTS-R are identical to those of LibriTTS, with only the sound quality
improved. Experimental results show that the LibriTTS-R ground-truth samples
showed significantly improved sound quality compared to those in LibriTTS. In
addition, neural end-to-end TTS trained with LibriTTS-R achieved speech
naturalness on par with that of the ground-truth samples. The corpus is freely
available for download from \url{http://www.openslr.org/141/}.Comment: Accepted to Interspeech 202
The Japanese space gravitational wave antenna; DECIGO
DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future
Japanese space gravitational wave antenna. DECIGO is expected to open a new window of
observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing
various mysteries of the universe such as dark energy, formation mechanism of supermassive
black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of
three drag-free spacecraft, whose relative displacements are measured by a differential Fabry–
Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre-
DECIGO first and finally DECIGO in 2024
DECIGO pathfinder
DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article
The status of DECIGO
DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consists of three drag-free spacecraft arranged in an equilateral triangle with 1000 km arm lengths whose relative displacements are measured by a differential Fabry-Perot interferometer, and four units of triangular Fabry-Perot interferometers are arranged on heliocentric orbit around the sun. DECIGO is vary ambitious mission, we plan to launch DECIGO in era of 2030s after precursor satellite mission, B-DECIGO. B-DECIGO is essentially smaller version of DECIGO: B-DECIGO consists of three spacecraft arranged in an triangle with 100 km arm lengths orbiting 2000 km above the surface of the earth. It is hoped that the launch date will be late 2020s for the present
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