56 research outputs found
Spectrogram Analysis of Blood Pressure on Neonates with Hypoxic Ischemic Encephalopathy (HIE)
This paper explores the correlation between blood pressure fluctuations and the severity of Hypoxic Ischemic Encephalopathy (HIE). Via isolating particular frequency bands of blood pressure signal and calculating their power, the researcher was able to discern patients with different HIE severity and verified the assumption that less fluctuation in blood pressure is correlated with more severe brain injury. Furthermore, the researcher attempted to construct a prediction algorithm based on power within certain frequency bands of the blood pressure signal
A Deep Learning Loss Function based on Auditory Power Compression for Speech Enhancement
Deep learning technology has been widely applied to speech enhancement. While
testing the effectiveness of various network structures, researchers are also
exploring the improvement of the loss function used in network training.
Although the existing methods have considered the auditory characteristics of
speech or the reasonable expression of signal-to-noise ratio, the correlation
with the auditory evaluation score and the applicability of the calculation for
gradient optimization still need to be improved. In this paper, a
signal-to-noise ratio loss function based on auditory power compression is
proposed. The experimental results show that the overall correlation between
the proposed function and the indexes of objective speech intelligibility,
which is better than other loss functions. For the same speech enhancement
model, the training effect of this method is also better than other comparison
methods.Comment: 7 pages, 4 figure
Research on Key Technologies of Infrastructure Digitalization based on Multimodal Spatial Data
Since NASA put forward the concept of the digital twin in 2010, many
industries have put forward the dynamic goal of digital development, and the
transportation industry is also among them. With more and more companies laying
out on this virgin land, the digital twin transportation industry has grown
rapidly and gradually formed a complete scientific research system. However,
under the largely mature framework, there are still many loophole problems that
need to be solved. In the process of constructing a road network with point
cloud information, we summarize several major features of the point cloud
collected by laser scanners and analyze the potential problems of constructing
the network, such as misjudging the feature points as ground points and grid
voids. On this basis, we reviewed relevant literature and proposed targeted
solutions, such as building a point cloud pyramid modeled after the image
pyramid, expanding the virtual grid, etc., applying CSF for ground-point cloud
extraction, and constructing a road network model using the PTD (progressive
density-based filter) algorithm. For the problem of road sign detection, we
optimize the remote sensing data in the ground point cloud by enhancing the
information density using edge detection, improving the data quality by
removing the low intensity points, and achieving 90% accuracy of road text
recognition using PaddleOCR and Densenet. As for the real-time digital twin
traffic, we design the P2PRN network using the backbone of MPR-GAN for 2D
feature generation and SuperGlue for 2D feature matching, rendering the
viewpoints according to the matching optimization points, completing the
multimodal matching task after several iterations, and successfully calculating
the road camera position with 10{\deg} and 15m accuracy.Comment: 20 pages, in Chinese language, 12 figure
On decoder-only architecture for speech-to-text and large language model integration
Large language models (LLMs) have achieved remarkable success in the field of
natural language processing, enabling better human-computer interaction using
natural language. However, the seamless integration of speech signals into LLMs
has not been explored well. The "decoder-only" architecture has also not been
well studied for speech processing tasks. In this research, we introduce
Speech-LLaMA, a novel approach that effectively incorporates acoustic
information into text-based large language models. Our method leverages
Connectionist Temporal Classification and a simple audio encoder to map the
compressed acoustic features to the continuous semantic space of the LLM. In
addition, we further probe the decoder-only architecture for speech-to-text
tasks by training a smaller scale randomly initialized speech-LLaMA model from
speech-text paired data alone. We conduct experiments on multilingual
speech-to-text translation tasks and demonstrate a significant improvement over
strong baselines, highlighting the potential advantages of decoder-only models
for speech-to-text conversion
Icariin Attenuates M1 Activation of Microglia and Aβ Plaque Accumulation in the Hippocampus and Prefrontal Cortex by Up-Regulating PPARγ in Restraint/Isolation-Stressed APP/PS1 Mice
BackgroundStudies have shown that psychosocial stress is involved in Alzheimer’s disease (AD) pathogenesis; it induces M1 microglia polarization and production of pro-inflammatory cytokines, leading to neurotoxic outcomes and decreased β-amyloid (Aβ) clearance. Icariin has been proven to be an effective anti-inflammatory agent and to activate peroxisome proliferator-activated receptors gamma (PPARγ) which induces the M2 phenotype in the microglia. However, whether restraint/isolation stress reduces the clearance ability of microglia by priming and polarizing microglia to the M1 phenotype, and the effects of icariin in attenuating the inflammatory response and relieving the pathological changes of AD are still unclear.MethodsAPP/PS1 mice (male, aged 3 months) were randomly divided into a control group, a restraint/isolation stress group, and a restraint/isolation stress + icariin group. The restraint/isolation stress group was subjected to a paradigm to build a depressive animal model. Sucrose preference, open field, elevated plus maze, and Y maze test were used to assess the stress paradigm. The Morris water maze test was performed to evaluate spatial reference learning and memory. Enzyme-linked immunosorbent assay and immunohistochemistry were used to identify the microglia phenotype and Aβ accumulation. Western blotting was used to detect the expression of PPARγ in the hippocampus and prefrontal cortex (PFC).ResultsRestraint/isolation stress induced significant depressive-like behaviors in APP/PS1 mice at 4 months of age and memory impairment at 10 months of age, while 6 months of icariin administration relieved the memory damage. Restraint/isolation stressed mice had elevated pro-inflammatory cytokines, decreased anti-inflammatory cytokines, increased Aβ plaque accumulation and more M1 phenotype microglia in the hippocampus and PFC at 10 months of age, while 6 months of icariin administration relieved these changes. Moreover, restraint/isolation stressed mice had down-regulated PPARγ expression in the hippocampus and PFC at 10 months of age, while 6 months of icariin administration reversed the alteration, especially in the hippocampus.ConclusionRestraint/isolation stress induced depressive-like behaviors and spatial memory damage, over-expression of M1 microglia markers and more severe Aβ accumulation by suppressing PPARγ in APP/PS1 mice. Icariin can be considered a new treatment option as it induces the switch of the microglia phenotype by activating PPARγ
Preparation of molecularly imprinted polymer for selective solid-phase extraction and simultaneous determination of five sulfonylurea herbicides in cereals
Molecular imprinting polymer (MIP) has been increasingly employed for sulfonylurea herbicides (SUHs) detection in different matrices. A novel MIP that was effective as a highly class-selective sorbent in molecularly imprinted solid-phase extraction (MISPE) was successfully prepared for isolation and purification of SUHs, namely, metsulfuron-methyl, chlorsulfuron, chlorimuron-ethyl, prosulfuron, and pyrazosulfuron-ethyl, in rice, corn and soybean samples. The MIP was synthesized by precipitation polymerization using metsulfuron-methyl as the template, 4-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, and MeCN as the porogen. The polymerization system of the MIP was optimized, and its adsorption performances were evaluated by comparing its adsorption isotherms and adsorption kinetics with those of a non-imprinted polymer (NIP). Following MISPE for extracting and enriching SUHs from rice, corn and soybean samples, high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was performed. Acceptable recoveries were observed at SUHs contaminant concentrations of 10, 20 and 40 μg/L: from 77.56 to 99.81%, with relative standard deviations of <13.8% (n = 5) for all samples. The limits of detection for the five SUHs were 0.21-0.26 μg/L. The results demonstrated that the proposed MISPE-HPLC-MS/MS method is an effective approach for the simultaneous and sensitive determination of the five SUHs in rice, corn and soybean samples
Sciences for The 2.5-meter Wide Field Survey Telescope (WFST)
The Wide Field Survey Telescope (WFST) is a dedicated photometric survey
facility under construction jointly by the University of Science and Technology
of China and Purple Mountain Observatory. It is equipped with a primary mirror
of 2.5m in diameter, an active optical system, and a mosaic CCD camera of 0.73
Gpix on the main focus plane to achieve high-quality imaging over a field of
view of 6.5 square degrees. The installation of WFST in the Lenghu observing
site is planned to happen in the summer of 2023, and the operation is scheduled
to commence within three months afterward. WFST will scan the northern sky in
four optical bands (u, g, r, and i) at cadences from hourly/daily to
semi-weekly in the deep high-cadence survey (DHS) and the wide field survey
(WFS) programs, respectively. WFS reaches a depth of 22.27, 23.32, 22.84, and
22.31 in AB magnitudes in a nominal 30-second exposure in the four bands during
a photometric night, respectively, enabling us to search tremendous amount of
transients in the low-z universe and systematically investigate the variability
of Galactic and extragalactic objects. Intranight 90s exposures as deep as 23
and 24 mag in u and g bands via DHS provide a unique opportunity to facilitate
explorations of energetic transients in demand for high sensitivity, including
the electromagnetic counterparts of gravitational-wave events detected by the
second/third-generation GW detectors, supernovae within a few hours of their
explosions, tidal disruption events and luminous fast optical transients even
beyond a redshift of 1. Meanwhile, the final 6-year co-added images,
anticipated to reach g about 25.5 mag in WFS or even deeper by 1.5 mag in DHS,
will be of significant value to general Galactic and extragalactic sciences.
The highly uniform legacy surveys of WFST will also serve as an indispensable
complement to those of LSST which monitors the southern sky.Comment: 46 pages, submitted to SCMP
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