Bayes Risk Transducer: Transducer with Controllable Alignment Prediction

Automatic speech recognition (ASR) based on transducers is widely used. In training, a transducer maximizes the summed posteriors of all paths. The path with the highest posterior is commonly defined as the predicted alignment between the speech and the transcription. While the vanilla transducer does not have a prior preference for any of the valid paths, this work intends to enforce the preferred paths and achieve controllable alignment prediction. Specifically, this work proposes Bayes Risk Transducer (BRT), which uses a Bayes risk function to set lower risk values to the preferred paths so that the predicted alignment is more likely to satisfy specific desired properties. We further demonstrate that these predicted alignments with intentionally designed properties can provide practical advantages over the vanilla transducer. Experimentally, the proposed BRT saves inference cost by up to 46% for non-streaming ASR and reduces overall system latency by 41% for streaming ASR

Reproducing Whisper-Style Training Using an Open-Source Toolkit and Publicly Available Data

Pre-training speech models on large volumes of data has achieved remarkable success. OpenAI Whisper is a multilingual multitask model trained on 680k hours of supervised speech data. It generalizes well to various speech recognition and translation benchmarks even in a zero-shot setup. However, the full pipeline for developing such models (from data collection to training) is not publicly accessible, which makes it difficult for researchers to further improve its performance and address training-related issues such as efficiency, robustness, fairness, and bias. This work presents an Open Whisper-style Speech Model (OWSM), which reproduces Whisper-style training using an open-source toolkit and publicly available data. OWSM even supports more translation directions and can be more efficient to train. We will publicly release all scripts used for data preparation, training, inference, and scoring as well as pre-trained models and training logs to promote open science.Comment: Accepted at ASRU 202

Draft genome sequence of the Tibetan antelope

The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission. Both the highland American pika, and the Tibetan antelope have signals of positive selection for genes involved in DNA repair and the production of ATPase. Genes associated with hypoxia seem to have experienced convergent evolution. Thus, our study suggests that common genetic mechanisms might have been utilized to enable high-altitude adaptation

OX40-OX40L interaction promotes proliferation and activation of lymphocytes via NFATc1 in ApoE-deficient mice.

BACKGROUND: Our previous studies have shown that OX40-OX40L interaction regulates the expression of nuclear factor of activated T cells c1(NFATc1) in ApoE(-/-) mice during atherogenesis. The aim of this study was to investigate whether OX40-OX40L interaction promotes Th cell activation via NFATc1 in ApoE(-/-) mice. METHODS AND RESULTS: The lymphocytes isolated from spleen of ApoE (-/-) mice were cultured with anti-CD3 mAb in the presence or absence of anti-OX40 or anti-OX40L antibodies. The expression of NFATc1 mRNA and protein in isolated lymphocytes were measured by real time PCR (RT-PCR) and flow cytometry (FCM), respectively. The proliferation of lymphocytes was analyzed by MTT method,and the expression of IL-2, IL-4 and IFN-γ in the cultured cells and supernatant were measured by RT-PCR and enzyme-linked immunosorbent assary (ELISA), respectively. After stimulating OX40-OX40L signal pathway, the expression of NFATc1 and the proliferation of leukocytes were significantly increased. Anti-OX40L suppressed the expression of NFATc1 in lymphocytes of ApoE-/- mice. Anti-OX40L or the NFATc1 inhibitor (CsA) markedly suppressed the cell proliferation induced by anti-OX40. Moreover, the expression of IL-2 and IFN-γ was increased in lymphocytes induced by OX40-OX40L interaction. Blocking OX40-OX40L interaction or NFATc1 down-regulated the expression of IL-2 and IFN-γ, but didn't alter the expression of IL-4 in supernatants. CONCLUSION: These results suggest that OX40-OX40L interaction promotes the proliferation and activation of lymphocytes through NFATc1

Clinical implications of elevated serum soluble CD137 levels in patients with acute coronary syndrome

OBJECTIVES: Atherosclerosis is a chronic inflammatory disease. Research has focused on identifying specific serum biomarkers to detect vulnerable plaques. These markers serve as diagnostic tools for acute coronary syndrome and assist in identifying high-risk patients. However, the existing data are limited and conflicting. This study tested the hypothesis that CD137 levels identify patients with acute coronary syndrome who are at a heightened risk for recurrent cardiac events. METHODS: The levels of soluble CD137 (sCD137) were measured using ELISA in 180 patients with acute coronary syndrome and 120 patients with acute chest pain. Platelet activation was assessed by flow cytometry. Receiver operating characteristic curve analysis was performed to evaluate the prognostic characteristics of sCD137. RESULTS: The levels of sCD137 were elevated in 75 patients with acute coronary syndromes and 20 patients with acute chest pain (>35.0 ng/ml). In patients with acute coronary syndrome, elevated sCD137 levels (>35.0 ng/ml) indicated an increased risk for major adverse cardiovascular events (OR =1.93, 95% CI: 1.39-2.54). Elevated serum levels of sCD137 and cTnT were correlated with a significantly increased risk of major adverse cardiovascular events in both groups after 30 days, six months and nine months of follow-up. The increased sCD137 levels were significantly correlated with the levels of troponin I (r = 0.4799, p<0.001). Importantly, 26 patients with normal cTnI levels had acute coronary syndrome. However, elevated sCD137 levels identified these patients as a being high-risk subgroup (OR = 2.14, 95% CI: 1.25-4.13). CONCLUSIONS: Elevated sCD137 levels indicate an increased risk of cardiovascular events in patients with acute coronary syndrome. Soluble CD137 may be a useful prognostic marker or indicator for adverse events in patients with acute coronary syndrome