1,820 research outputs found
Magnetic surface on nonmagnetic bulk of electride Hf2S
Recent experiment reported the self-passivated electride Hf2S with excellent
stability and continuous electrocatalytic ability [S. H. Kang et al., Sci. Adv.
6, eaba7416 (2020)]. Starting from its 2H-type layered structure, we have
studied the electronic, magnetic, and transport properties of the electride
Hf2S in the monolayer and multilayer forms by combining first-principles
electronic structure calculations and Kubo formula approach. Our calculations
indicate that these thin films of Hf2S electride are both dynamically and
thermodynamically stable. Astonishingly, the calculations further show that the
outmost Hf atoms and the surface electron gas of the Hf2S multilayers are spin
polarized, while the inner Hf atoms and the electron gas in the interlayer
regions remain nonmagnetic. Due to the magnetic surface, the multilayer Hf2S
exhibits many unusual transport properties such as the surface anomalous Hall
effect and the electric-field-induced layer Hall effect. Our theoretical
predictions on Hf2S call for future experimental verification.Comment: 5 pages, 5 figures, 34 reference
Soluble Epoxide Hydrolase in Atherosclerosis
Like many eicosanoids, epoxyeicosatrienoic acids (EETs) have multiple biological functions, including reduction of blood pressure, inflammation, and atherosclerosis in multiple species. Hydration of EETs by the soluble epoxide hydrolase (sEH) is the major route of their degradation to the less bioactive diols. Inhibition of the sEH stabilizes EETs, thus, enhancing the beneficial effects of EETs. Human data show an association of sEH (Ephx2) gene polymorphisms with increased risk of atherosclerosis and cardiovascular diseases. These data suggest a potential therapeutic effect of sEH inhibitors (sEHI) in the treatment of atherosclerosis. Indeed, two laboratories reported independently that using different sEHIs in apolipoprotein E–deficient mice significantly attenuated atherosclerosis development and aneurysm formation. The antiatherosclerotic effects of sEHI are correlated with elevation in EET levels and associated with reduction of low-density lipoprotein and elevation of high-density lipoprotein cholesterols, as well as attenuation of expression of proinflammatory genes and proteins. In addition, the antihypertensive effects and improvement of endothelial function also contribute to the mechanism of the antiatherosclerotic effects of sEHI. The broad spectrum of biological action of EETs and sEHIs with multiple biological beneficial actions provides a promising new class of therapeutics for atherosclerosis and other cardiovascular diseases
DNS: A multi-scale deconvolution semantic segmentation network for joint detection and segmentation
Real-time semantic segmentation has become crucial in many applications such as medical image analysis and autonomous driving. In this paper, we introduce a single semantic segmentation network, called DNS, for joint object detection and segmentation task. We take advantage of multi-scale deconvolution mechanism to perform real time computations. To this goal, down-scale and up-scale streams are utilized to combine the multi-scale features for the final detection and segmentation task. By using the proposed DNS, not only the tradeoff between accuracy and cost but also the balance of detection and segmentation performance are settled. Experimental results for PASCAL VOC datasets show competitive performance for joint object detection and segmentation task
miRBaseConverter: an R/Bioconductor package for converting and retrieving miRNA name, accession, sequence and family information in different versions of miRBase
Abstract
Background
miRBase is the primary repository for published miRNA sequence and annotation data, and serves as the “go-to” place for miRNA research. However, the definition and annotation of miRNAs have been changed significantly across different versions of miRBase. The changes cause inconsistency in miRNA related data between different databases and articles published at different times. Several tools have been developed for different purposes of querying and converting the information of miRNAs between different miRBase versions, but none of them individually can provide the comprehensive information about miRNAs in miRBase and users will need to use a number of different tools in their analyses.
Results
We introduce miRBaseConverter, an R package integrating the latest miRBase version 22 available in Bioconductor to provide a suite of functions for converting and retrieving miRNA name (ID), accession, sequence, species, version and family information in different versions of miRBase. The package is implemented in R and available under the GPL-2 license from the Bioconductor website (
http://bioconductor.org/packages/miRBaseConverter/
). A Shiny-based GUI suitable for non-R users is also available as a standalone application from the package and also as a web application at
http://nugget.unisa.edu.au:3838/miRBaseConverter
. miRBaseConverter has a built-in database for querying miRNA information in all species and for both pre-mature and mature miRNAs defined by miRBase. In addition, it is the first tool for batch querying the miRNA family information. The package aims to provide a comprehensive and easy-to-use tool for miRNA research community where researchers often utilize published miRNA data from different sources.
Conclusions
The Bioconductor package miRBaseConverter and the Shiny-based web application are presented to provide a suite of functions for converting and retrieving miRNA name, accession, sequence, species, version and family information in different versions of miRBase. The package will serve a wide range of applications in miRNA research and could provide a full view of the miRNAs of interest.https://deepblue.lib.umich.edu/bitstream/2027.42/146768/1/12859_2018_Article_2531.pd
Holographic Storage of Biphoton Entanglement
Coherent and reversible storage of multi-photon entanglement with a multimode
quantum memory is essential for scalable all-optical quantum information
processing. Although single photon has been successfully stored in different
quantum systems, storage of multi-photon entanglement remains challenging
because of the critical requirement for coherent control of photonic
entanglement source, multimode quantum memory, and quantum interface between
them. Here we demonstrate a coherent and reversible storage of biphoton
Bell-type entanglement with a holographic multimode atomic-ensemble-based
quantum memory. The retrieved biphoton entanglement violates Bell's inequality
for 1 microsecond storage time and a memory-process fidelity of 98% is
demonstrated by quantum state tomography.Comment: 5 pages, 4 figures, accepted by Phys. Rev. Let
Involvement of the TLR4/NF-κB Signaling Pathway in the Repair of Esophageal Mucosa Injury in Rats with Gastroesophageal Reflux Disease
Background/Aims: Numerous studies have highlighted the activation of NF-κB in the esophageal mucosa during the early stages of gastroesophageal reflux disease (GERD). The present study aimed to investigate the role of the TLR4/NF-κB signaling pathway in GERD rat models. Methods: Wistar rats (n = 60) were recruited to establish a GERD animal model. Distal esophageal pH was assessed, followed by determination of the contents of thiobarbituric acid-reactive species (TBARS) and reactive oxygen species (ROS) in esophageal mucosa homogenate. ELISA was employed to detect the levels of inflammatory factors (IL-6, IL-8, IL-10 and TNF-α) in esophageal mucosa. The expression of MMP-3, MPP-9, Cldn1 and Cldn4 was determined by immunohistochemistry. RT-qPCR and western blot analysis were applied to evaluate the protein expressions in TLR4/NF-κB signaling pathway, while TUNEL staining was utilized to examine the apoptosis rate in the esophageal mucosal tissues. Results: Distal esophageal pH of the rats was higher in the GERD + PDTC group than in other groups. Levels of inflammatory factors in esophageal mucosal tissues were downregulated with the inhibition of NF-κB, which was determined to be associated with the decreased contents of TBARS and ROS. Moreover, decreased MMP-3 and MPP-9 in addition to elevated Cldn1 and Cldn4 were detected in the esophageal mucosa as a result of the inactivation of NF-κB. The TLR4/NF-κB signaling pathway-related proteins (TLR4, NF-κB and IκBα); the rate of apoptosis was demonstrated to be suppressed in the GERD + PDTC group, while inactivating NF-κB was found to alleviate the tissue damage observed in the esophageal mucosa. Conclusion: The key findings of the current study demonstrate that the inactivation of the TLR4/NF-κB signaling pathway alleviates oxidative stress injury and promotes the repair of esophageal mucosal injury among rats with GERD, highlighting a potential novel GERD mechanism
Exploring Speech Enhancement for Low-resource Speech Synthesis
High-quality and intelligible speech is essential to text-to-speech (TTS)
model training, however, obtaining high-quality data for low-resource languages
is challenging and expensive. Applying speech enhancement on Automatic Speech
Recognition (ASR) corpus mitigates the issue by augmenting the training data,
while how the nonlinear speech distortion brought by speech enhancement models
affects TTS training still needs to be investigated. In this paper, we train a
TF-GridNet speech enhancement model and apply it to low-resource datasets that
were collected for the ASR task, then train a discrete unit based TTS model on
the enhanced speech. We use Arabic datasets as an example and show that the
proposed pipeline significantly improves the low-resource TTS system compared
with other baseline methods in terms of ASR WER metric. We also run empirical
analysis on the correlation between speech enhancement and TTS performances.Comment: Submitted to ICASSP 202
Gait analysis in a murine model of collagen-induced arthritis
Murine collagen-induced arthritis (CIA) has become a valuable animal model for elucidating pathogenic mechanisms and evaluating therapeutic effects for rheumatoid arthritis. Recent advances in digital imaging and computer technology have enabled gait analysis to develop into a powerful tool for objectively detecting functional deficits in human and animal models. The present study explored the use of non-invasive video-capture gait analysis in the evaluation of a murine CIA model. CIA was induced in 45 female DBA/1LacJ mice (8 to 10 weeks old) by immunization with lyophilized bovine articular type II collagen. Gait parameters were determined by ventral plane videography and were correlated to traditional arthritis clinical scores. Our results showed that increases in clinical scores that measure the severity of CIA corresponded to changes in multiple gait parameters that reflect both morphologic (increases in paw area) and functional (increase in stride frequency, decrease in stride length, hind-limb paw placement angle, as well as stride, stance, and braking times) deficits. Our work indicated that the non-invasive video-capture device may be used as a simple and objective data acquisition system for quantifying gait disturbances in CIA mice for the investigation of mechanisms and the evaluation of therapeutic agents
Anomalous Dome-like Superconductivity in RE2(Cu1-xNix)5As3O2(RE=La, Pr, Nd)
Significant manifestation of interplay of superconductivity and charge
density wave, spin density wave or magnetism is dome-like variation in
superconducting critical temperature (Tc) for cuprate, iron-based and heavy
Fermion superconductors. Overall behavior is that the ordered temperature is
gradually suppressed and the Tc is enhanced under external control parameters.
Many phenomena like pesudogap, quantum critical point and strange metal emerge
in the different doping range. Exploring dome-shaped Tc in new superconductors
is of importance to detect emergent effects. Here, we report that the
observation of superconductivity in new layered Cu-based compound RE2Cu5As3O2
(RE=La, Pr, Nd), in which the Tc exhibits dome-like variation with maximum Tc
of 2.5 K, 1.2 K and 1.0 K as substituting Cu by large amount of Ni ions. The
transitions of T* in former two compounds can be suppressed by either Ni doping
or rare earth replacement. Simultaneously, the structural parameters like As-As
bond length and c/a ratio exhibit unusual variations as Ni-doping level goes
through the optimal value. The robustness of superconductivity, up to 60% of Ni
doping, reveals the unexpected impurity effect on inducing and enhancing
superconductivity in this novel layered materialsComment: 16 pages, 5 figures. Comments are welcom
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