148 research outputs found
Analysis of miRNAs involved in mouse brain injury upon Coxsackievirus A6 infection
IntroductionCoxsackievirus A6 (CV-A6) has emerged as the predominant epidemic strain responsible for hand, foot and mouth disease (HFMD). CV-A6 infection can result in severe clinical manifestations, including encephalitis, meningitis, and potentially life-threatening central nervous system disorders. Our previous research findings demonstrated that neonatal mice infected with CV-A6 exhibited limb weakness, paralysis, and ultimately succumbed to death. However, the underlying mechanism of CV-A6-induced nervous system injury remains elusive. Numerous reports have highlighted the pivotal role of miRNAs in various viral infections.MethodsSeparately established infection and control groups of mice were used to create miRNA profiles of the brain tissues before and after CV-A6 transfection, followed by experimental verification, prediction, and analysis of the results.ResultsAt 2 days post-infection (dpi), 4 dpi, and 2dpi vs 4dpi, we identified 175, 198 and 78 significantly differentially expressed miRNAs respectively using qRT-PCR for validation purposes. Subsequently, we predicted target genes of these differentially expressed miRNAs and determined their potential targets through GO (Gene Ontology) enrichment analysis and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis. Finally, we verified the miRNA-mRNA pairing via double luciferase experiments while confirming functional enrichment of target genes through Western Blotting analyses.DiscussionThe results from this study suggest that transcriptional regulation, neuronal necrosis, pro-inflammatory cytokine release, and antiviral immunity are all implicated in the pathogenesis of central nervous system injury in mice infected with CV-A6. Brain injury resulting from CV-A6 infection may involve multiple pathways, including glial cell activation, neuronal necrosis, synaptic destruction, degenerative diseases of the nervous system. It can even encompass destruction of the blood-brain barrier, leading to central nervous system injury. The dysregulated miRNAs and signaling pathways discovered in this study provide valuable insights for further investigations into the pathogenesis of CV-A6
Modern Datalog on the GPU
Modern deductive database engines (e.g., LogicBlox and Souffl\'e) enable
their users to write declarative queries which compute recursive deductions
over extensional data, leaving their high-performance operationalization (query
planning, semi-na\"ive evaluation, and parallelization) to the engine. Such
engines form the backbone of modern high-throughput applications in static
analysis, security auditing, social-media mining, and business analytics.
State-of-the-art engines are built upon nested loop joins over explicit
representations (e.g., BTrees and tries) and ubiquitously employ range indexing
to accelerate iterated joins. In this work, we present GDlog: a GPU-based
deductive analytics engine (implemented as a CUDA library) which achieves
significant performance improvements (5--10x or more) versus prior systems.
GDlog is powered by a novel range-indexed SIMD datastructure: the hash-indexed
sorted array (HISA). We perform extensive evaluation on GDlog, comparing it
against both CPU and GPU-based hash tables and Datalog engines, and using it to
support a range of large-scale deductive queries including reachability, same
generation, and context-sensitive program analysis. Our experiments show that
GDlog achieves performance competitive with modern SIMD hash tables and beats
prior work by an order of magnitude in runtime while offering more favorable
memory footprint
Topological triply-degenerate point with double Fermi arcs
Unconventional chiral particles have recently been predicted to appear in
certain three dimensional (3D) crystal structures containing three- or
more-fold linear band degeneracy points (BDPs). These BDPs carry topological
charges, but are distinct from the standard twofold Weyl points or fourfold
Dirac points, and cannot be described in terms of an emergent relativistic
field theory. Here, we report on the experimental observation of a topological
threefold BDP in a 3D phononic crystal. Using direct acoustic field mapping, we
demonstrate the existence of the threefold BDP in the bulk bandstructure, as
well as doubled Fermi arcs of surface states consistent with a topological
charge of 2. Another novel BDP, similar to a Dirac point but carrying nonzero
topological charge, is connected to the threefold BDP via the doubled Fermi
arcs. These findings pave the way to using these unconventional particles for
exploring new emergent physical phenomena
Research Progress in the Regulation Mechanisms of White and Brown Adipose Tissue in the Body by Functionally Active Factors
Brown adipose tissue (BAT) improves the metabolic level of the body by promoting energy expenditure, which can contribute to the prevention and treatment of metabolic diseases such as obesity and diabetes, and BAT has become a new target for the treatment of metabolic diseases. BAT activity enhancement in the body is a hot topic but also a challenge for researchers, and research and analysis of functionally active factors in foods that regulate BAT can help to develop new nutritional activators. In this paper, we summarize the development and thermogenesis of BAT and thermogenesis-related factors, and review active ingredients in foods that regulate brown fat and their mechanisms of action, and briefly introduce the effects of white adipose tissue (WAT) and BAT on the body’s health. We also discuss recent developments in understanding the role of BAT in regulating energy metabolic balance and various diseases in the body. We hope that the present review will provide a theoretical basis for future development of brown adipose nutritional activators and improvement of individualized healthy dietary management programs in order to prevent and treat various diseases
Enhanced Quadratic Video Interpolation
With the prosperity of digital video industry, video frame interpolation has
arisen continuous attention in computer vision community and become a new
upsurge in industry. Many learning-based methods have been proposed and
achieved progressive results. Among them, a recent algorithm named quadratic
video interpolation (QVI) achieves appealing performance. It exploits
higher-order motion information (e.g. acceleration) and successfully models the
estimation of interpolated flow. However, its produced intermediate frames
still contain some unsatisfactory ghosting, artifacts and inaccurate motion,
especially when large and complex motion occurs. In this work, we further
improve the performance of QVI from three facets and propose an enhanced
quadratic video interpolation (EQVI) model. In particular, we adopt a rectified
quadratic flow prediction (RQFP) formulation with least squares method to
estimate the motion more accurately. Complementary with image pixel-level
blending, we introduce a residual contextual synthesis network (RCSN) to employ
contextual information in high-dimensional feature space, which could help the
model handle more complicated scenes and motion patterns. Moreover, to further
boost the performance, we devise a novel multi-scale fusion network (MS-Fusion)
which can be regarded as a learnable augmentation process. The proposed EQVI
model won the first place in the AIM2020 Video Temporal Super-Resolution
Challenge.Comment: Winning solution of AIM2020 VTSR Challenge (in conjunction with ECCV
2020
Towards Better Fairness-Utility Trade-off: A Comprehensive Measurement-Based Reinforcement Learning Framework
Machine learning is widely used to make decisions with societal impact such
as bank loan approving, criminal sentencing, and resume filtering. How to
ensure its fairness while maintaining utility is a challenging but crucial
issue. Fairness is a complex and context-dependent concept with over 70
different measurement metrics. Since existing regulations are often vague in
terms of which metric to use and different organizations may prefer different
fairness metrics, it is important to have means of improving fairness
comprehensively. Existing mitigation techniques often target at one specific
fairness metric and have limitations in improving multiple notions of fairness
simultaneously. In this work, we propose CFU (Comprehensive Fairness-Utility),
a reinforcement learning-based framework, to efficiently improve the
fairness-utility trade-off in machine learning classifiers. A comprehensive
measurement that can simultaneously consider multiple fairness notions as well
as utility is established, and new metrics are proposed based on an in-depth
analysis of the relationship between different fairness metrics. The reward
function of CFU is constructed with comprehensive measurement and new metrics.
We conduct extensive experiments to evaluate CFU on 6 tasks, 3 machine learning
models, and 15 fairness-utility measurements. The results demonstrate that CFU
can improve the classifier on multiple fairness metrics without sacrificing its
utility. It outperforms all state-of-the-art techniques and has witnessed a
37.5% improvement on average
ALA: Naturalness-aware Adversarial Lightness Attack
Most researchers have tried to enhance the robustness of DNNs by revealing
and repairing the vulnerability of DNNs with specialized adversarial examples.
Parts of the attack examples have imperceptible perturbations restricted by Lp
norm. However, due to their high-frequency property, the adversarial examples
can be defended by denoising methods and are hard to realize in the physical
world. To avoid the defects, some works have proposed unrestricted attacks to
gain better robustness and practicality. It is disappointing that these
examples usually look unnatural and can alert the guards. In this paper, we
propose Adversarial Lightness Attack (ALA), a white-box unrestricted
adversarial attack that focuses on modifying the lightness of the images. The
shape and color of the samples, which are crucial to human perception, are
barely influenced. To obtain adversarial examples with a high attack success
rate, we propose unconstrained enhancement in terms of the light and shade
relationship in images. To enhance the naturalness of images, we craft the
naturalness-aware regularization according to the range and distribution of
light. The effectiveness of ALA is verified on two popular datasets for
different tasks (i.e., ImageNet for image classification and Places-365 for
scene recognition).Comment: 9 page
Low-Quality Training Data Only? A Robust Framework for Detecting Encrypted Malicious Network Traffic
Machine learning (ML) is promising in accurately detecting malicious flows in
encrypted network traffic; however, it is challenging to collect a training
dataset that contains a sufficient amount of encrypted malicious data with
correct labels. When ML models are trained with low-quality training data, they
suffer degraded performance. In this paper, we aim at addressing a real-world
low-quality training dataset problem, namely, detecting encrypted malicious
traffic generated by continuously evolving malware. We develop RAPIER that
fully utilizes different distributions of normal and malicious traffic data in
the feature space, where normal data is tightly distributed in a certain area
and the malicious data is scattered over the entire feature space to augment
training data for model training. RAPIER includes two pre-processing modules to
convert traffic into feature vectors and correct label noises. We evaluate our
system on two public datasets and one combined dataset. With 1000 samples and
45% noises from each dataset, our system achieves the F1 scores of 0.770,
0.776, and 0.855, respectively, achieving average improvements of 352.6%,
284.3%, and 214.9% over the existing methods, respectively. Furthermore, We
evaluate RAPIER with a real-world dataset obtained from a security enterprise.
RAPIER effectively achieves encrypted malicious traffic detection with the best
F1 score of 0.773 and improves the F1 score of existing methods by an average
of 272.5%
Quantitative modeling of streamer discharge branching in air
Streamer discharges are the primary mode of electric breakdown of air in
lightning and high voltage technology. Streamer channels branch many times,
which determines the developing tree-like discharge structure. Understanding
these branched structures is for example important to describe streamer coronas
in lightning research. We simulate branching of positive streamers in air using
a 3D fluid model where photoionization is included as a discrete and stochastic
process. The probability and morphology of branching are in good agreement with
dedicated experiments. This demonstrates that photoionization indeed provides
the noise that triggers branching, and we show that branching is remarkably
sensitive to the amount of photoionization. Our comparison is therefore one of
the first sensitive tests for Zheleznyak's photoionization model, confirming
its validity
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