2,211 research outputs found

    An Unsupervised Autoregressive Model for Speech Representation Learning

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    This paper proposes a novel unsupervised autoregressive neural model for learning generic speech representations. In contrast to other speech representation learning methods that aim to remove noise or speaker variabilities, ours is designed to preserve information for a wide range of downstream tasks. In addition, the proposed model does not require any phonetic or word boundary labels, allowing the model to benefit from large quantities of unlabeled data. Speech representations learned by our model significantly improve performance on both phone classification and speaker verification over the surface features and other supervised and unsupervised approaches. Further analysis shows that different levels of speech information are captured by our model at different layers. In particular, the lower layers tend to be more discriminative for speakers, while the upper layers provide more phonetic content.Comment: Accepted to Interspeech 2019. Code available at: https://github.com/iamyuanchung/Autoregressive-Predictive-Codin

    Occlusion of acute distal brachial, proximal radial and ulnar arteries in a young thrower

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    SummaryAcute arterial occlusion, a rare condition in throwers, requires early detection and treatment for avoiding further complications. Thus far, no study has mentioned the occurrence of distal brachial, proximal radial, and ulnar artery occlusion in baseball players. An adolescent baseball pitcher presented with acute occlusion of the distal brachial, proximal radial, or ulnar artery. The patient complained of a cold sensation in the hand, wrist, and distal forearm. On physical examination, decreased surface skin temperature, and no radial pulse in the wrist suggested arterial occlusion. Emergency angiography validated the clinical suspicion, and identified the arteries and sites of vascular occlusion. Surgery was performed to alleviate the occlusions, thereby resolving the preoperative complaints and abnormal findings. Furthermore, postoperative magnetic resonance imaging of the shoulder and elbow joint was conducted to determine the causes of arterial occlusion. The patient resumed pitching 4 months postoperatively, and has remained active and symptom free. Magnetic resonance imaging examination revealed no vascular abnormalities or bony or soft tissue in the shoulder or elbow region. With early detection and treatment, a favorable prognosis can be achieved in baseball pitchers with acute upper extremity arterial occlusion so that their pitching career is not jeopardized

    Majorana zero modes in a quantum Ising chain with longer-ranged interactions

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    A one-dimensional Ising model in a transverse field can be mapped onto a system of spinless fermions with p-wave superconductivity. In the weak-coupling BCS regime, it exhibits a zero energy Majorana mode at each end of the chain. Here, we consider a variation of the model, which represents a superconductor with longer ranged kinetic energy and pairing amplitudes, as is likely to occur in more realistic systems. It possesses a richer zero temperature phase diagram and has several quantum phase transitions. From an exact solution of the model these phases can be classified according to the number of Majorana zero modes of an open chain: 0, 1, or 2 at each end. The model posseses a multicritical point where phases with 0, 1, and 2 Majorana end modes meet. The number of Majorana modes at each end of the chain is identical to the topological winding number of the Anderson's pseudospin vector that describes the BCS Hamiltonian. The topological classification of the phases requires a unitary time-reversal symmetry to be present. When this symmetry is broken, only the number of Majorana end modes modulo 2 can be used to distinguish two phases. In one of the regimes, the wave functions of the two phase shifted Majorana zero modes decays exponentially in space but but in an oscillatory manner. The wavelength of oscillation is identical to the asymptotic connected spin-spin correlation of the XY-model in a transverse field to which our model is dual.Comment: 11 pages, 8 figures; brief clarifying comments added; few new references; this version is accepted in Phys. Rev.

    Prescription Patterns of Chinese Herbal Products for Osteoporosis in Taiwan: A Population-Based Study

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    Background. Traditional Chinese medicine (TCM) includes Chinese herbal products (CHPs), acupuncture, and traumatology manipulative therapies. TCM physicians often prescribe CHP to treat patients with osteoporosis; however, the drugs used and their patterns of prescriptions have yet to be characterized. This study, therefore, aimed to evaluate the CHP used for the treatment of osteoporosis in Taiwan and their prescription patterns. Methods. A cohort of one million randomly sampled cases from the National Health Insurance Research Database (NHIRD) was analyzed to evaluate the frequencies and percentages of herbal formula and single herb prescriptions for osteoporosis. Association rules were then applied to evaluate the CHP coprescription patterns and the prevalence of osteoporosis. Results. The osteoporosis cohort included 16 544 patients, of whom more than 70% had used TCM on one or more occasion. Of these patients, 4 292 (25.9%) had been hospitalized at least once because of fracture. Du-Huo-Ji-Sheng-Tang and Du Zhong (Cortex Eucommiae) were the most frequently prescribed herbal formula and single herb, respectively, for the treatment of osteoporosis. Conclusion. This study identified patterns of CHP use for the treatment of osteoporosis. However, further research is required to fully elucidate the efficacy and safety of these CHP

    Genome-Wide Sequence Variation among Mycobacterium avium Subspecies paratuberculosis Isolates: A Better Understanding of Johne’s Disease Transmission Dynamics

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    Mycobacterium avium subspecies paratuberculosis (M. ap), the causative agent of Johne’s disease, infects many farmed ruminants, wild-life animals, and recently isolated from humans. To better understand the molecular pathogenesis of these infections, we analyzed the whole-genome sequences of several M. ap and M. avium subspecies avium (M. avium) isolates to gain insights into genomic diversity associated with variable hosts and environments. Using Next-generation sequencing technology, all six M. ap isolates showed a high percentage of similarity (98%) to the reference genome sequence of M. ap K-10 isolated from cattle. However, two M. avium isolates (DT 78 and Env 77) showed significant sequence diversity (only 87 and 40% similarity, respectively) compared to the reference strain M. avium 104, a reflection of the wide environmental niches of this group of mycobacteria. Within the M. ap isolates, genomic rearrangements (insertions/deletions) were not detected, and only unique single nucleotide polymorphisms (SNPs) were observed among M. ap isolates. While more of the SNPs (~100) in M. ap genomes were non-synonymous, a total of ~6,000 SNPs were detected among M. avium genomes, most of them were synonymous suggesting a differential selective pressure between M. ap and M. avium isolates. In addition, SNPs-based phylo-genomics had a enough discriminatory power to differentiate between isolates from different hosts but yet suggesting a bovine source of infection to other animals examined in this study. Interestingly, the human isolate (M. ap 4B) was closely related to a M. ap isolate from a dairy facility, suggesting a common source of infection. Overall, the identified phylo-genomes further supported the idea of a common ancestor to both M. ap and M. avium isolates. Genome-wide analysis described here could provide a strong foundation for a population genetic structure that could be useful for the analysis of mycobacterial evolution and for the tracking of Johne’s disease transmission among animals

    Celecoxib extends C. elegans lifespan via inhibition of insulin‐like signaling but not cyclooxygenase‐2 activity

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86911/1/ACEL_688_sm_FigS1-S2-TableS1-S2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/86911/2/j.1474-9726.2011.00688.x.pd
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