663 research outputs found

    Rhythm-Flexible Voice Conversion without Parallel Data Using Cycle-GAN over Phoneme Posteriorgram Sequences

    Full text link
    Speaking rate refers to the average number of phonemes within some unit time, while the rhythmic patterns refer to duration distributions for realizations of different phonemes within different phonetic structures. Both are key components of prosody in speech, which is different for different speakers. Models like cycle-consistent adversarial network (Cycle-GAN) and variational auto-encoder (VAE) have been successfully applied to voice conversion tasks without parallel data. However, due to the neural network architectures and feature vectors chosen for these approaches, the length of the predicted utterance has to be fixed to that of the input utterance, which limits the flexibility in mimicking the speaking rates and rhythmic patterns for the target speaker. On the other hand, sequence-to-sequence learning model was used to remove the above length constraint, but parallel training data are needed. In this paper, we propose an approach utilizing sequence-to-sequence model trained with unsupervised Cycle-GAN to perform the transformation between the phoneme posteriorgram sequences for different speakers. In this way, the length constraint mentioned above is removed to offer rhythm-flexible voice conversion without requiring parallel data. Preliminary evaluation on two datasets showed very encouraging results.Comment: 8 pages, 6 figures, Submitted to SLT 201

    BIOADI: a machine learning approach to identifying abbreviations and definitions in biological literature

    Get PDF
    BACKGROUND: To automatically process large quantities of biological literature for knowledge discovery and information curation, text mining tools are becoming essential. Abbreviation recognition is related to NER and can be considered as a pair recognition task of a terminology and its corresponding abbreviation from free text. The successful identification of abbreviation and its corresponding definition is not only a prerequisite to index terms of text databases to produce articles of related interests, but also a building block to improve existing gene mention tagging and gene normalization tools. RESULTS: Our approach to abbreviation recognition (AR) is based on machine-learning, which exploits a novel set of rich features to learn rules from training data. Tested on the AB3P corpus, our system demonstrated a F-score of 89.90% with 95.86% precision at 84.64% recall, higher than the result achieved by the existing best AR performance system. We also annotated a new corpus of 1200 PubMed abstracts which was derived from BioCreative II gene normalization corpus. On our annotated corpus, our system achieved a F-score of 86.20% with 93.52% precision at 79.95% recall, which also outperforms all tested systems. CONCLUSION: By applying our system to extract all short form-long form pairs from all available PubMed abstracts, we have constructed BIOADI. Mining BIOADI reveals many interesting trends of bio-medical research. Besides, we also provide an off-line AR software in the download section on http://bioagent.iis.sinica.edu.tw/BIOADI/

    Soft tagging of overlapping high confidence gene mention variants for cross-species full-text gene normalization

    Get PDF
    Abstract Background Previously, gene normalization (GN) systems are mostly focused on disambiguation using contextual information. An effective gene mention tagger is deemed unnecessary because the subsequent steps will filter out false positives and high recall is sufficient. However, unlike similar tasks in the past BioCreative challenges, the BioCreative III GN task is particularly challenging because it is not species-specific. Required to process full-length articles, an ineffective gene mention tagger may produce a huge number of ambiguous false positives that overwhelm subsequent filtering steps while still missing many true positives. Results We present our GN system participated in the BioCreative III GN task. Our system applies a typical 2-stage approach to GN but features a soft tagging gene mention tagger that generates a set of overlapping gene mention variants with a nearly perfect recall. The overlapping gene mention variants increase the chance of precise match in the dictionary and alleviate the need of disambiguation. Our GN system achieved a precision of 0.9 (F-score 0.63) on the BioCreative III GN test corpus with the silver annotation of 507 articles. Its TAP-k scores are competitive to the best results among all participants. Conclusions We show that despite the lack of clever disambiguation in our gene normalization system, effective soft tagging of gene mention variants can indeed contribute to performance in cross-species and full-text gene normalization.</p

    Effects of human parvovirus B19 VP1 unique region protein on macrophage responses

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Activity of secreted phospholipase A (sPLA2) has been implicated in a wide range of cellular responses. However, little is known about the function of human parvovirus B19-VP1 unique region (VP1u) with sPLA2 activity on macrophage.</p> <p>Methods</p> <p>To investigate the roles of B19-VP1u in response to macrophage, phospholipase A2 activity, cell migration assay, phagocytosis activity, metalloproteinase assay, RT-PCR and immunoblotting were performed.</p> <p>Results</p> <p>In the present study, we report that migration, phagocytosis, IL-6, IL-1β mRNA, and MMP9 activity are significantly increased in RAW264.7 cells by B19-VP1u protein with sPLA2 activity, but not by B19-VP1uD175A protein that is mutated and lacks sPLA2 activity. Additionally, significant increases of phosphorylated ERK1/2 and JNK proteins were detected in macrophages that were treated with B19-VP1u protein, but not when they were treated with B19-VP1uD175A protein.</p> <p>Conclusion</p> <p>Taken together, our experimental results suggest that B19-VP1u with sPLA2 activity affects production of IL-6, IL-1β mRNA, and MMP9 activity, possibly through the involvement of ERK1/2 and JNK signaling pathways. These findings could provide clues in understanding the role of B19-VP1u and its sPLA2 enzymatic activity in B19 infection and B19-related diseases.</p

    Tetra­butyl­ammonium bis­[4,4′-dimethyl-2,2′-(3,7-dimethyl-1H-4,2,1-benzothiaza­siline-1,1-di­yl)dibenzene­thiol­ato]vanadium(III) acetonitrile tetra­solvate

    Get PDF
    In the title compound, [N(C4H9)4][V(C23H21NS3Si)2]·4CH3CN, the VIII atom (site symmetry ) is coordinated by two N,S,S′-tridentate 4,4′-dimethyl-2,2′-(3,7-dimethyl-1H-4,2,1-benzothiaza­siline-1,1-di­yl)dibenzene­thiol­ate ligands in a distorted trans-VN2S4 octa­hedral geometry. The complete cation is generated by crystallographic twofold symmetry, with the V atom lying on the rotation axis. The unusual ligand arose from nucleophilic attack on the coordinated nitrile by the thiol­ate precursor and reduction of nitrile to the imidate

    Structural and optical properties of ZnMgO nanostructures formed by Mg in-diffused ZnO nanowires

    Get PDF
    Abstract ZnMgO nanostructures with wurtzite phase were prepared by thermal diffusion of Mg into the ZnO nanowires. As ZnO light-emitting devices have been operated by using ZnMgO layers as energy barrier layers to confine the carriers, it is essential to realize the characterization of ZnMgO particularly. In this work, the Mg content in Zn 1Àx Mg x O alloy determined by X-ray diffraction (XRD) and photoluminescence (PL) shows a good coincidence. The variation of lattice constant and the blueshift of near-band-edge emission indicate that Zn 2+ ions are successfully substituted by Mg 2+ ions in the ZnO lattice. In Raman-scattering studies, the change of E 2 (high) phonon line shape in ZnO:Mg nanostructures reveals the microscopic substitutional disorder. In addition to the host phonons of ZnO, two additional bands around 383 and 510 cm À1 are presumably attributed to the Mg-related vibrational modes

    Bioequivalence Evaluation of Two Formulations of Celecoxib 200 mg Capsules in Healthy volunteers by using a validated LC/MS/MS method

    Get PDF
    The bioequivalence study to compare a new formulation of celecoxib to its reference formulation was designed as an open-label, randomized, single-dose, two-way crossover, comparative bioavailability study by using a validated LC/MS/MS method. In order to determine the plasma concentrations of celecoxib, a sensitive LC/MS/MS method was developed. The method was validated to possess adequate specificity, linearity, precision, accuracy and stability. The linearity of calibration curve was assessed between the concentration intervals (5–2000 ng/mL) with a correlation coefficient over 0.999. Regarding pharmacokinetic investigation, the mean celecoxib AUC0-t values from the test and reference drug formulations were 7360.44 ± 1714.14 h•ng/mL and 7267.48 ± 2077.68 h•ng/mL, respectively, and the corresponding AUC0-∞ values were 8197.45 ± 2040.31 h•ng/mL and 7905.54 ± 2286.12 h•ng/mL, respectively. The Cmax of the test and reference drugs was 705.30 ± 290.63 ng/mL and 703.86 ± 329.91 ng/mL, respectively, and the corresponding Tmax was 3.4 ± 1.6 h and 2.9 ± 1.4 h. Lastly, the T1/2 values of the test and reference drugs were 13.9 ± 7.9 h and 12.9 ± 7.7 h, respectively. The 90% confidence intervals for AUC0-t, AUC0-∞, and Cmax were 97.00-108.85, 98.01-112.09, and 93.20-116.13, respectively, satisfying the bioequivalence criteria of 80-125% range. In conclusion, these results demonstrated that the bioequivalence of two formulations of celecoxib was established successfully by utilizing present developed LC/MS/MS method

    Relationship between Obesity-related Hormone Peptides and Quality of Life in Obese Women among Different Traditional Chinese Medicine Syndrome Groups

    Get PDF
    AbstractThe aim of this study was to explore the relationship between obesity-related hormone peptides and quality of life in obese women among different traditional Chinese medicine (TCM) syndrome groups (證型 zhèng xíng). 260 obese women met with age between 20 and 65years old and body mass index (BMI) ≧ 27kg/m2, were recruited. The participants filled out a questionnaire on obese TCM syndrome groups, which was designed by professional TCM doctors, and two questionnaires on quality of life (QOL), WHOQOL-BREF Taiwan version and MOS Short Form-12 (SF-12). Data of biochemical characteristics and obesity-related hormone peptides were collected at the same time. According to the responses provided, the obese subjects were classified into spleen deficiency with dampness encumbrance syndrome (脾虛濕阻證 pí xū shī zǔ zhèng; SDD), stomach heat with dampness encumbrance syndrome (胃熱濕阻證 wèi rè shī zǔ zhèng; SHD), liver depression and qi stagnation syndrome (肝鬱氣滯證 gān yù qì zhì zhèng; LDQ), dual spleen-kidney deficiency syndrome (脾腎兩虛證 pí shèn liǎng xū zhèng; SKD), yin deficiency with internal heat syndrome (陰虛內熱證 yīn xū nèi rè zhèng; YDI) and a control group. For physical conditions, SDD group had significantly higher means in weight and BMI compared with the control group. The insulin and leptin levels in SHD group were significantly higher than those in the control group. The LDQ group showed marked decrease in mental condition scores compared with the control group. This study found that obese women in the SDD group were fatter than those in the control group. SHD group might have greater influence on the regulation of obesity-related hormone peptides. The LDQ group had poor QOL than the control group. Analysis of TCM syndrome groups among obese women merits further investigation
    corecore