165 research outputs found
m6A modifications regulate intestinal immunity and rotavirus infection
N6-methyladenosine (m6A) is an abundant mRNA modification and affects many biological processes. However, how m6A levels are regulated during physiological or pathological processes such as virus infections, and the in vivo function of m6A in the intestinal immune defense against virus infections are largely unknown. Here, we uncover a novel antiviral function of m6A modification during rotavirus (RV) infection in small bowel intestinal epithelial cells (IECs). We found that rotavirus infection induced global m6A modifications on mRNA transcripts by down-regulating the m6a eraser ALKBH5. Mice lacking the m6A writer enzymes METTL3 in IECs
Abstraction-Based Verification of Approximate Pre-Opacity for Control Systems
In this paper, we consider the problem of verifying pre-opacity for
discrete-time control systems. Pre-opacity is an important information-flow
security property that secures the intention of a system to execute some secret
behaviors in the future. Existing works on pre-opacity only consider non-metric
discrete systems, where it is assumed that intruders can distinguish different
output behaviors precisely. However, for continuous-space control systems whose
output sets are equipped with metrics (which is the case for most real-world
applications), it is too restrictive to assume precise measurements from
outside observers. In this paper, we first introduce a concept of approximate
pre-opacity by capturing the security level of control systems with respect to
the measurement precision of the intruder. Based on this new notion of
pre-opacity, we propose a verification approach for continuous-space control
systems by leveraging abstraction-based techniques. In particular, a new
concept of approximate pre-opacity preserving simulation relation is introduced
to characterize the distance between two systems in terms of preserving
pre-opacity. This new system relation allows us to verify pre-opacity of
complex continuous-space control systems using their finite abstractions. We
also present a method to construct pre-opacity preserving finite abstractions
for a class of discrete-time control systems under certain stability
assumptions.Comment: Discrete Event Systems, Opacity, Formal Abstraction
Biochemical Variation Among Normal Equine Carpal and Tarsocrural Joint Fluids are Detected by Infrared Spectral Characteristics and A Modified Approach to Linear Discriminant Analysis
Research into osteoarthritis diagnostics has evolved from traditional methods that are only useful in more advanced clinical disease, towards the discovery of biomarkers that are predictive or reflective of preclinical joint disease. The potential of Fourier transform infrared spectroscopy (FTIR) coupled with chemometrics has been demonstrated as useful for the assessment of biomolecular responses to disease. Joint fluid was collected from 105 clinically normal antebrachiocarpal (AC), midcarpal (MC) and tarsocrural (TCRL) joints. Thin films were prepared and FTIR absorbance spectra in the mid-infrared region recorded. Interferograms were signal averaged and Fourier transformed to generate spectra with a nominal resolution of 4 cm-1. Comparisons among joints were made using a novel modified method similar to linear discriminant analysis, which maximized the difference of between-group variance minus within-group variance, followed by permutation testing. Differences within animal between contralateral pairs of joints were minimal. Significant differences among AC, MC and TCRL joint fluid spectra were found. The range of biomolecular differences among these normal joints as characterized by FTIR indicates that interarticular variation within the horse needs to be considered for ongoing research, especially when utilizing within-horse joints as controls
Rotavirus NSP1 contributes to intestinal viral replication, pathogenesis, and transmission
Rotavirus (RV)-encoded nonstructural protein 1 (NSP1), the product of gene segment 5, effectively antagonizes host interferon (IFN) signaling via multiple mechanisms. Recent studies with the newly established RV reverse genetics system indicate that NSP1 is not essential for the replication of the simian RV SA11 strain in cell culture. However, the role of NSP1 in RV infectio
Conditional GANs with Auxiliary Discriminative Classifier
Conditional generative models aim to learn the underlying joint distribution
of data and labels to achieve conditional data generation. Among them, the
auxiliary classifier generative adversarial network (AC-GAN) has been widely
used, but suffers from the problem of low intra-class diversity of the
generated samples. The fundamental reason pointed out in this paper is that the
classifier of AC-GAN is generator-agnostic, which therefore cannot provide
informative guidance for the generator to approach the joint distribution,
resulting in a minimization of the conditional entropy that decreases the
intra-class diversity. Motivated by this understanding, we propose a novel
conditional GAN with an auxiliary discriminative classifier (ADC-GAN) to
resolve the above problem. Specifically, the proposed auxiliary discriminative
classifier becomes generator-aware by recognizing the class-labels of the real
data and the generated data discriminatively. Our theoretical analysis reveals
that the generator can faithfully learn the joint distribution even without the
original discriminator, making the proposed ADC-GAN robust to the value of the
coefficient hyperparameter and the selection of the GAN loss, and stable during
training. Extensive experimental results on synthetic and real-world datasets
demonstrate the superiority of ADC-GAN in conditional generative modeling
compared to state-of-the-art classifier-based and projection-based conditional
GANs.Comment: ICML 202
Modeling and Characteristic Analysis of Wireless Ultrasonic Vibration Energy Transmission Channels through Planar and Curved Metal Barriers
Wireless ultrasonic vibration energy transmission systems through metal barriers based on piezoelectric transducers have drawn a lot of focus due to the advantage of nonpenetration of the barriers, thus maintaining the integrity of sealed structures. It is meaningful to investigate appropriate modeling methods and to characterize such wireless ultrasonic energy transmission channels with different geometric shapes. In this paper, equivalent circuit modeling and finite element modeling methods are applied to the planar metal barrier channel, and a 3-dimensional finite element modeling method is applied to the cylindrical metallic barrier channel. Meanwhile, the experimental setup is established and measurements are carried out to validate the effectiveness of the corresponding modeling methods. The results show that Leach’s equivalent circuit modeling method and finite element modeling method are nearly similarly effective in characterizing the planar metal barrier channel. But for a cylindrical metal barrier, only the three-dimensional finite element modeling method is effective. Furthermore, we found that, for the planar barrier, the effect of standing waves on the efficiency of wireless energy transmission is dominated. But for the curved barrier, only the resonant phenomenon of the piezoelectric transducer exists
A recombinant murine-like rotavirus with Nano-Luciferase expression reveals tissue tropism, replication dynamics, and virus transmission
Rotaviruses (RVs) are one of the main causes of severe gastroenteritis, diarrhea, and death in children and young animals. While suckling mice prove to be highly useful small animal models of RV infection and pathogenesis, direct visualization tools are lacking to track the temporal dynamics of RV replication and transmissibilit
NL2Formula: Generating Spreadsheet Formulas from Natural Language Queries
Writing formulas on spreadsheets, such as Microsoft Excel and Google Sheets,
is a widespread practice among users performing data analysis. However,
crafting formulas on spreadsheets remains a tedious and error-prone task for
many end-users, particularly when dealing with complex operations. To alleviate
the burden associated with writing spreadsheet formulas, this paper introduces
a novel benchmark task called NL2Formula, with the aim to generate executable
formulas that are grounded on a spreadsheet table, given a Natural Language
(NL) query as input. To accomplish this, we construct a comprehensive dataset
consisting of 70,799 paired NL queries and corresponding spreadsheet formulas,
covering 21,670 tables and 37 types of formula functions. We realize the
NL2Formula task by providing a sequence-to-sequence baseline implementation
called fCoder. Experimental results validate the effectiveness of fCoder,
demonstrating its superior performance compared to the baseline models.
Furthermore, we also compare fCoder with an initial GPT-3.5 model (i.e.,
text-davinci-003). Lastly, through in-depth error analysis, we identify
potential challenges in the NL2Formula task and advocate for further
investigation.Comment: To appear at EACL 202
A Mild Dyssynchronous Contraction Pattern Detected by SPECT Myocardial Perfusion Imaging Predicts Super-Response to Cardiac Resynchronization Therapy
Background: Using single photon emission computed tomography myocardial perfusion imaging (SPECT MPI) with phase analysis (PA), we aimed to identify the predictive value of a new contraction pattern in cardiac resynchronization therapy (CRT) response. Methods: Left ventricular mechanical dyssynchrony (LVMD) was evaluated using SPECT MPI with PA in non-ischemic dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB) indicated for CRT. CRT super-response was defined as LV ejection fraction (EF) ≥50% or an absolute increase of LVEF \u3e15%. The LV contraction was categorized as the mild dyssynchronous pattern when the phase standard deviation (PSD) ≤ 40.3° and phase histogram bandwidth (PBW) ≤ 111.9°, otherwise it was defined as severe dyssynchronous pattern which was further characterized as U-shaped, heterogeneous or homogenous pattern. Results: The final cohort comprised 74 patients, including 32 (43.2%) in mild dyssynchronous group, 17 (23%) in U-shaped group, 19 (25.7%) in heterogeneous group, and 6 (8.1%) in homogenous group. The mild dyssynchronous group had lower PSD and PBW than U-shaped, heterogeneous, and homogenous groups ( \u3c 0.0001). Compared to patients with the heterogeneous pattern, the odds ratios (ORs) with 95% confidence intervals (CIs) for CRT super-response were 10.182(2.43-42.663), 12.8(2.545-64.372), and 2.667(0.327-21.773) for patients with mild dyssynchronous, U-shaped, and homogenous pattern, respectively. After multivariable adjustment, mild dyssynchronous group remained associated with increased CRT super-response (adjusted OR 5.709, 95% CI 1.152-28.293). Kaplan-Meier curves showed that mild dyssynchronous group demonstrated a better long-term prognosis. Conclusions: The mild dyssynchronous pattern in patients with DCM is associated with an increased CRT super-response and better long-term prognosis
Laser processing of printed copper interconnects on polymer substrates
With the increasing demand for integration of electronics embedded within devices there has been a consequent increase in the requirement for the deposition of electrically conductive materials to form connecting tracks on or within non-traditional substrate materials, such as temperature sensitive polymers, that may also have non-planar surfaces. In this work, micron scale copper powder based materials were deposited onto acrylic and glass substrates and then selectively laser processed to form electrically conductive copper tracks. Before deposition, the copper powder was chemically treated to remove the surface oxide and subsequently protected with a self-assembled monolayer coating. The copper was then patterned onto the substrate either as a dry powder confined within pre-formed grooves, or was combined with a binder to be printed as a paste. A CO2 laser was then used to heat the copper powder in air, leading to tracks that showed good electrical conductivity. At low laser power levels, the tracks appeared largely unchanged from the original material, but showed measureable conductivity. With higher laser power levels the tracks showed evidence of partial melting of the surface layers and further reductions in resistivity, to values approximately 30 times those of bulk copper, were obtained
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