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Article ; Online: QOCT-Net: A Physics-Informed Neural Network for Intravascular Optical Coherence Tomography Attenuation Imaging.

Zheng, Sun / Shuyan, Wang / Yingsa, Hou / Meichen, Sun

IEEE journal of biomedical and health informatics

2023 Volume 27, Issue 8, Page(s) 3958–3969

Abstract: Intravascular optical coherence tomography (IVOCT) provides high-resolution, depth-resolved images of coronary arterial microstructure by acquiring backscattered light. Quantitative attenuation imaging is important for accurate characterization of tissue ...

Abstract	Intravascular optical coherence tomography (IVOCT) provides high-resolution, depth-resolved images of coronary arterial microstructure by acquiring backscattered light. Quantitative attenuation imaging is important for accurate characterization of tissue components and identification of vulnerable plaques. In this work, we proposed a deep learning method for IVOCT attenuation imaging based on the multiple scattering model of light transport. A physics-informed deep network named Quantitative OCT Network (QOCT-Net) was designed to recover pixel-level optical attenuation coefficients directly from standard IVOCT B-scan images. The network was trained and tested on simulation and in vivo datasets. Results showed superior attenuation coefficient estimates both visually and based on quantitative image metrics. The structural similarity, energy error depth and peak signal-to-noise ratio are improved by at least 7%, 5% and 12.4%, respectively, compared with the state-of-the-art non-learning methods. This method potentially enables high-precision quantitative imaging for tissue characterization and vulnerable plaque identification.
MeSH term(s)	Humans ; Tomography, Optical Coherence/methods ; Plaque, Atherosclerotic/diagnostic imaging ; Neural Networks, Computer ; Coronary Vessels ; Computer Simulation
Language	English
Publishing date	2023-08-07
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2695320-1
ISSN	2168-2208 ; 2168-2194
ISSN (online)	2168-2208
ISSN	2168-2194
DOI	10.1109/JBHI.2023.3276422
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Article ; Online: Application of high-resolution processing in seismic data based on an improved synchrosqueezing transform

Chen Yu / Shuyan Wang / Lifang Cheng

Frontiers in Earth Science, Vol

2022 Volume 10

Abstract: This study proposes a high-resolution processing technique for seismic data based on the improved synchrosqueezing transform (SST). The SST rearranges the complex spectrum of the wavelet transform along the frequency axis. However, the energy is not ... ...

Abstract	This study proposes a high-resolution processing technique for seismic data based on the improved synchrosqueezing transform (SST). The SST rearranges the complex spectrum of the wavelet transform along the frequency axis. However, the energy is not concentrated in the position with the faster frequency change rate. To overcome these problems, the proposed method first transformed the seismic signal into an analytical one via Hilbert transformation and then determined the phase correction value (x0(t)) before and after the transformation. This was achieved using the instantaneous frequency attribute (ω(t)) of the analytical signal and a specific frequency (ω0) selected as the dominant frequency of the input data to adjust the change rate of the signal frequency before the SST falls close to zero, which can improve the time–frequency resolution after compression transformation. The essence of this method only adjusts the phase of the signal before and after transformation, without affecting the inverse expression of the SST. The one- and two-dimensional model data results show that the proposed method can better identify the time–frequency distribution characteristics of seismic signals and improve their resolution and the focusing effect in the time–frequency domain. The proposed method shows good prospects for application in gas reservoir detection and identification.
Keywords	improved synchrosqueezing transform ; generalized Fourier transform ; time–frequency analysis ; seismic data ; high resolution ; Science ; Q
Language	English
Publishing date	2022-08-01T00:00:00Z
Publisher	Frontiers Media S.A.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Multi-Level Credit Assignment for Cooperative Multi-Agent Reinforcement Learning

Lei Feng / Yuxuan Xie / Bing Liu / Shuyan Wang

Applied Sciences, Vol 12, Iss 14, p

2022 Volume 6938

Abstract: Multi-agent reinforcement learning (MARL) has become more and more popular over recent decades, and the need for high-level cooperation is increasing every day because of the complexity of the real-world environment. However, the multi-agent credit ... ...

Abstract	Multi-agent reinforcement learning (MARL) has become more and more popular over recent decades, and the need for high-level cooperation is increasing every day because of the complexity of the real-world environment. However, the multi-agent credit assignment problem that serves as the main obstacle to high-level coordination is still not addressed properly. Though lots of methods have been proposed, none of them have thought to perform credit assignments across multi-levels. In this paper, we aim to propose an approach to learning a better credit assignment scheme by credit assignment across multi-levels. First, we propose a hierarchical model that consists of the manager level and the worker level. The manager level incorporates the dilated Gated Recurrent Unit (GRU) to focus on high-level plans and the worker level uses GRU to execute primitive actions conditioned on high-level plans. Then, one centralized critic is designed for each level to learn each level’s credit assignment scheme. To this end, we construct a novel hierarchical MARL algorithm, named MLCA, which can achieve multi-level credit assignment. We also conduct experiments on three classical and challenging tasks to demonstrate the performance of the proposed algorithm against three baseline methods. The results show that our method gains great performance improvement across all maps that require high-level cooperation.
Keywords	multi-agent reinforcement learning ; hierarchical MARL ; credit assignment ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	006
Language	English
Publishing date	2022-07-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Design and Analysis of Cam Wave Generator Based on Free Deformation in Non-Working Area of the Flexspline

Shuyan Wang / Dongliang Li / Shiteng Mao / Bingkui Chen

Applied Sciences, Vol 11, Iss 6049, p

2021 Volume 6049

Abstract: Deformation stress of a flexspline under the action of a wave generator directly affects the service life of the flexspline and meshing quality of meshing pair. This study proposed a new deformation model for a flexspline, which incorporates forced ... ...

Abstract	Deformation stress of a flexspline under the action of a wave generator directly affects the service life of the flexspline and meshing quality of meshing pair. This study proposed a new deformation model for a flexspline, which incorporates forced deformation in the working area and free deformation in the non-working area, keeping the deformation shape unchanged during rotating. Based on this assumption of a deformation model, the mathematical model is further established, and the design approach of a cam wave generator is developed with the deflection curve of the ring structure. Then, a sample design with a double eccentric arc cam wave generator based on this deformation model is developed and analyzed in FEM. The results show that the deformation stress of the flexspline can be improved by relaxing the forced deformation in the non-working area, and the selected deformation shape can also remain unchanged during rotating. Moreover, the stress distribution and the maximum stress value could be improved with the variation of the combination coefficient, especially for the wrap angle.
Keywords	harmonic drive ; flexspline ; deflection ; forced deformation ; cam wave generator ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	629
Language	English
Publishing date	2021-06-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Incidence and Prognostic Role of Pleural Effusion in Patients with Pulmonary Embolism

Ping Li / Jing An / Shuyan Wang / Xueru Hu / Tingting Zeng / Chun Wan / Yongchun Shen / Tao Wang

Journal of Clinical Medicine, Vol 12, Iss 2315, p

A Systematic Review and Meta-Analysis

2023 Volume 2315

Abstract: Background: Pleural effusion is a common pulmonary embolism (PE) complication, which has been documented to increase the risk of death in PE and relate to disease progression. However, the incidence of pleural effusion varies among studies and its ... ...

Abstract	Background: Pleural effusion is a common pulmonary embolism (PE) complication, which has been documented to increase the risk of death in PE and relate to disease progression. However, the incidence of pleural effusion varies among studies and its association with PE outcome is still unclear. This study sought to determine the pooled incidence and prognostic value of pleural effusion events in patients with PE. Methods: We systematically searched the PubMed, EMBASE, SCOPE, Web of Science, Cochrane, LILACS, CINAHL, EBSCO, AMED, and OVID databases from the inception of each database to 7 September 2022 with a restriction on human studies, to identify studies assessing the association between pleural effusion and PE including all prospective and retrospective clinical studies. An exploratory meta-analysis was performed using a random-effects model. We evaluated the heterogeneity and performed subgroup analyses. Results: The final meta-analysis included 29 studies involving 13,430 PE patients. The pooled incidence of pleural effusion in PE patients was 41.2% (95% CI: 35.7–46.6%), which tended to be unilateral (pooled incidence: 60.8%, 95% CI: 45.7–75.8%) and small (pooled incidence: 85.9%, 95% CI: 82.6–89.1%). Pooled analysis using a random-effects model (I 2 = 53.2%) showed that pleural effusion was associated with an increased risk of 30-day mortality (RR 2.19, 95% CI: 1.53–3.15, p < 0.001, I 2 = 67.1%) and in-hospital mortality (RR 2.39, 95% CI: 1.85–3.09, p < 0.001, I 2 = 37.1%) in patients with PE. Conclusions: Our meta-analysis found that PE patients had a high incidence of pleural effusion, which was usually unilateral and small. Pleural effusion generally increases 30-day and in-hospital mortality in patients with PE, and it is recommended that physicians be aware of the risk of death from PE, especially when patients have pleural effusion. Further investigations focusing on PE with pleural effusion are warranted.
Keywords	pulmonary embolism ; pleural effusion ; systematic review ; meta-analysis ; Medicine ; R
Subject code	610
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Linguistic Attitudes towards Putonghua

Shuyan WANG

Canadian Social Science, Vol 5, Iss 2, Pp 41-

the case of migrants from Hubei in Canton

2009 Volume 45

Abstract: This paper describes the linguistic attitudes of migrants from Hubei working in Caton towards Putonghua, which is a language of mass communication, open to the outside world and adorned by all the prestige of modernity and power. This explicit judgement ... ...

Abstract	This paper describes the linguistic attitudes of migrants from Hubei working in Caton towards Putonghua, which is a language of mass communication, open to the outside world and adorned by all the prestige of modernity and power. This explicit judgement indicates both their linguistic taste and their social identity. Key words: Linguistic attitudes; Putonghua; Migrants from Hubei; Canton
Keywords	Linguistic attitudes ; Putonghua ; Migrants from Hubei ; Canton ; Social sciences (General) ; H1-99 ; Social Sciences ; H ; DOAJ:Social Sciences
Language	English
Publishing date	2009-04-01T00:00:00Z
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Delta Opioid Peptide [d-Ala2, d-Leu5] Enkephalin (DADLE) Exerts a Cytoprotective Effect in Astrocytes Exposed to Oxygen-Glucose Deprivation by Inducing Autophagy

Shuyan Wang / Xiaoqiong Cao / Yale Duan / Guangming Zhang

Cell Transplantation, Vol

2019 Volume 28

Abstract: Astrocytes protection and functional regulation are important strategies to protect against neuronal damage caused by ischemia. Activation of the delta opioid receptor (DOR) could reduce astrocytes damage, although the mechanism remains unclear. The ... ...

Abstract	Astrocytes protection and functional regulation are important strategies to protect against neuronal damage caused by ischemia. Activation of the delta opioid receptor (DOR) could reduce astrocytes damage, although the mechanism remains unclear. The present study aimed to test the effect of DOR activation on autophagy in astrocytes exposed to oxygen-glucose deprivation (OGD), and to further investigate whether this effect has a protective effect on astrocytes. Primary cultured rat cortical astrocytes were treated with various doses of [ d -Ala2, d -Leu5]-Enkephalin (DADLE, a selective DOR agonist) followed by 6 h OGD. Cell viability was evaluated by CCK-8 assay and lactate dehydrogenase release. Autophagic vacuole was analyzed with LC3 immunofluorescent staining. The levels of autophagy and apoptosis-related proteins were analyzed by western blot. Results demonstrated that treatment with 10 nM DADLE was sufficient to increase cell viability and induced autophagy in astrocytes. The DADLE-induced autophagy displayed a cytoprotective effect on astrocytes. Inhibition of autophagy by 3-methyladenine (3-MA, an autophagy inhibitor) reversed the protective effect of DADLE. Naltrindole (a DOR antagonist) only partially antagonized the role of DADLE, which indicated that DADLE might have a cytoprotective mechanism independent of DOR. Further results showed that DADLE significantly enhanced the level of Bcl-2 protein and reduced the level of Bax protein in astrocytes exposed to OGD. Our results suggest a novel mechanism in which DADLE induces autophagy in astrocytes and exerts cytoprotective effects by inhibiting apoptosis.
Keywords	Medicine ; R
Subject code	610
Language	English
Publishing date	2019-06-01T00:00:00Z
Publisher	SAGE Publishing
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Comparison of Volatiles in Different Jasmine Tea Grade Samples Using Electronic Nose and Automatic Thermal Desorption-Gas Chromatography-Mass Spectrometry Followed by Multivariate Statistical Analysis

Shuyan Wang / Feng Zhao / Wenxi Wu / Pengjie Wang / Naixing Ye

Molecules, Vol 25, Iss 2, p

2020 Volume 380

Abstract: Chinese jasmine tea is a type of flower-scented tea, which is produced by mixing green tea with the Jasminum sambac flower repeatedly. Both the total amount and composition of volatiles absorbed from the Jasminum sambac flower are mostly responsible for ... ...

Abstract	Chinese jasmine tea is a type of flower-scented tea, which is produced by mixing green tea with the Jasminum sambac flower repeatedly. Both the total amount and composition of volatiles absorbed from the Jasminum sambac flower are mostly responsible for its sensory quality grade. This study aims to compare volatile organic compound (VOC) differences in authoritative jasmine tea grade samples. Automatic thermal desorption-gas-chromatography-mass spectrometry (ATD-GC-MS) and electronic nose (E-nose), followed by multivariate data analysis is conducted. Consequently, specific VOCs with a positive or negative correlation to the grades are screened out. Partial least squares-discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) show a satisfactory discriminant effect on rank. It is intriguing to find that the E-nose is good at distinguishing the grade difference caused by VOC concentrations but is deficient in identifying essential aromas that attribute to the unique characteristics of excellent grade jasmine tea.
Keywords	chinese jasmine tea ; tea grade ; volatile organic compounds ; electronic nose (e-nose) ; automatic thermal desorption-gas-chromatography- mass spectrometry (atd-gc-ms) ; multivariate statistical analysis ; Organic chemistry ; QD241-441
Subject code	540
Language	English
Publishing date	2020-01-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Trial of a prehospital intervention with traditional Chinese medicine for acute stroke (TRACE)

Yuanyuan Chen / Ziyu Tian / Shuyan Wang / Hongmei Liu / Yanfang Liu / Wei Peng / Xinxing Lai / Dahe Qi / Lingbo Kong / Ying Gao

Frontiers in Pharmacology, Vol

Protocol for a mixed-methods research study

2022 Volume 13

Abstract: Background: As the only traditional Chinese medicine injection approved by the China Food and Drug Administration for use as stroke first aid in ambulances, Xingnaojing Injection (XNJI) has been widely used in cases of both acute ischemic stroke (IS) and ...

Abstract	Background: As the only traditional Chinese medicine injection approved by the China Food and Drug Administration for use as stroke first aid in ambulances, Xingnaojing Injection (XNJI) has been widely used in cases of both acute ischemic stroke (IS) and intracerebral hemorrhage (ICH). However, there is no robust clinical evidence regarding the efficacy and safety of the early use of XNJI during stroke first aid. The main purpose of this trial is to observe whether XNJI, intravenously administered within 24 h of onset in the prehospital ambulance setting, protects against early neurological deterioration (END) on the third day of onset in patients with acute stroke.Methods: The Trial of a prehospital intervention with traditional Chinese medicine for acute stroke (TRACE) is a Mixed-Methods research (MMR) study that involves a combination of quantitative and qualitative research. The quantitative research part of this project is a prospective, multicenter, observational, clinical registry study, for which we aimed to recruit 1,000 patients with acute stroke (IS and ICH). Based on our observation of whether XNJI was intravenously administered within 24 h of onset in the prehospital ambulance setting, patients with acute stroke will be divided into two groups: the exposure group comprising patients who were intravenously administered XNJI and the nonexposure group comprising patients who were not. The primary outcome is early neurological deterioration (END) on the third day of onset defined as an increase of 2 or more points in the National Institute of Health Stroke Scale score between baseline and day 3. In addition, based on the aforementioned quantitative research, qualitative research will be conducted by interviewing emergency doctors about their knowledge and attitude regarding XNJI used for stroke first aid.Discussion: The results of the TRACE study will provide preliminary evidence for the relationship between XNJI used within 24 h of onset and the presence of END on the third day after stroke onset; it ...
Keywords	prehospital intervention ; traditional chinese medicine ; xingnaojing injection ; acute stroke ; study protocol ; mixed methods research ; Therapeutics. Pharmacology ; RM1-950
Subject code	150
Language	English
Publishing date	2022-08-01T00:00:00Z
Publisher	Frontiers Media S.A.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Granular restitution coefficient-based kinetic theory computations of bubbling fluidized beds

Xiaoxue, Jiang / Shuyan, Wang / Qinghong, Zhang / Baoli, Shao / Huilin, Lu

Powder technology. 2021 Dec., v. 394

2021

Abstract: The coefficient of restitution (CoR) is an empirical parameter in dense gas-particles computational fluid dynamics (CFD) by means of kinetic theory of granular flow (KTGF). A great sensitivity of CoR on predictions was found because of the existence of ... ...

Abstract	The coefficient of restitution (CoR) is an empirical parameter in dense gas-particles computational fluid dynamics (CFD) by means of kinetic theory of granular flow (KTGF). A great sensitivity of CoR on predictions was found because of the existence of multiple collisions of particles in fluidized beds. In present study, an empirical correlation of granular CoR is proposed using a coupled KTGF of Euler granular phase and the discrete element method (DEM) of Lagrange discrete particles. The CoR is calculated using statistical methodology according to relative velocity of two colliding discrete particles. The granular CoR is computed from granular volume fractions, indicating that the multiple collision effects on momentum conservation over collision at high granular volume fractions. The granular constitutive equations for the transport coefficients are solved according to granular CoR. The simulated bed expansions agreed with experimental measurements. The predicted granular pressure and viscosity are compared with measured data.
Keywords	fluid mechanics ; momentum ; technology ; viscosity
Language	English
Dates of publication	2021-12
Size	p. 825-837.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2021.09.018
Database	NAL-Catalogue (AGRICOLA)

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