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219 results on '"Yan, Jue"'

3. A generalized framework for direct discontinuous Galerkin methods for nonlinear diffusion equations

Author

Danis, Mustafa Engin and Yan, Jue

Subjects
Mathematics - Numerical Analysis, 65M12, 65M60
Abstract

In this study, we propose a unified, general framework for the direct discontinuous Galerkin methods. In the new framework, the antiderivative of the nonlinear diffusion matrix is not needed. This allows a simple definition of the numerical flux, which can be used for general diffusion equations with no further modification. We also present the nonlinear stability analyses of the new direct discontinuous Galerkin methods and perform several numerical experiments to evaluate their performance. The numerical tests show that the symmetric and the interface correction versions of the method achieve optimal convergence and are superior to the nonsymmetric version, which demonstrates optimal convergence only for problems with diagonal diffusion matrices but loses order for even degree polynomials with a non-diagonal diffusion matrix. Singular or blow-up solutions are also well captured with the new direct discontinuous Galerkin methods., Comment: 22 pages, 4 figures

Published
2022

4. Cell-average based neural network method for high dimensional parabolic differential equations

Author

Zhang, Hong, Huang, Hongying, and Yan, Jue

Subjects
Mathematics - Numerical Analysis
Abstract

In this paper, we introduce cell-average based neural network (CANN) method to solve high-dimensional parabolic partial differential equations. The method is based on the integral or weak formulation of partial differential equations. A feedforward network is considered to train the solution average of cells in neighboring time. Initial values and approximate solution at $t=\Delta t$ obtained by high order numerical method are taken as the inputs and outputs of network, respectively. We use supervised training combined with a simple backpropagation algorithm to train the network parameters. We find that the neural network has been trained to optimality for high-dimensional problems, the CFL condition is not strictly limited for CANN method and the trained network is used to solve the same problem with different initial values. For the high-dimensional parabolic equations, the convergence is observed and the errors are shown related to spatial mesh size but independent of time step size., Comment: 21 pages, 8 figures and 17 tables

Published
2022

6. Cell-average based neural network method for hyperbolic and parabolic partial differential equations

Author

Qiu, Changxin and Yan, Jue

Subjects
Mathematics - Numerical Analysis, Computer Science - Machine Learning
Abstract

Motivated by finite volume scheme, a cell-average based neural network method is proposed. The method is based on the integral or weak formulation of partial differential equations. A simple feed forward network is forced to learn the solution average evolution between two neighboring time steps. Offline supervised training is carried out to obtain the optimal network parameter set, which uniquely identifies one finite volume like neural network method. Once well trained, the network method is implemented as a finite volume scheme, thus is mesh dependent. Different to traditional numerical methods, our method can be relieved from the explicit scheme CFL restriction and can adapt to any time step size for solution evolution. For Heat equation, first order of convergence is observed and the errors are related to the spatial mesh size but are observed independent of the mesh size in time. The cell-average based neural network method can sharply evolve contact discontinuity with almost zero numerical diffusion introduced. Shock and rarefaction waves are well captured for nonlinear hyperbolic conservation laws.

Published
2021

7. A new direct discontinuous Galerkin method with interface correction for two-dimensional compressible Navier-Stokes equations

Author

Danis, Mustafa E. and Yan, Jue

Subjects
Mathematics - Numerical Analysis, 65M60, 76N20
Abstract

We propose a new formula for the nonlinear viscous numerical flux and extend the direct discontinuous Galerkin method with interface correction (DDGIC) of Liu and Yan (H. Liu, J. Yan, The direct discontinuous Galerkin (DDG) method for diffusion with interface corrections, Communications in Computational Physics 8 (3) (2010) 541) to compressible Navier-Stokes equations. The new DDGIC framework is based on the observation that the nonlinear diffusion can be represented as a sum of multiple individual diffusion processes corresponding to each conserved variable. A set of direction vectors corresponding to each individual diffusion process is defined and approximated by the average value of the numerical solution at the cell interfaces. The new framework only requires the computation of conserved variables' gradient, which is linear and approximated by the original direct DG numerical flux formula. The proposed method greatly simplifies the implementation, and thus, can be easily extended to general equations and turbulence models. Numerical experiments with $P_1$, $P_2$, $P_3$ and $P_4$ polynomial approximations are performed to verify the optimal $(k+1)^{th}$ high-order accuracy of the method. The new DDGIC method is shown to be able to accurately calculate physical quantities such as lift, drag, and friction coefficients as well as separation angle and Strouhal number., Comment: 26 pages, 7 figures

Published
2021
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8. Accuracy and Architecture Studies of Residual Neural Network solving Ordinary Differential Equations

Author

Qiu, Changxin, Bendickson, Aaron, Kalyanapu, Joshua, and Yan, Jue

Subjects
Mathematics - Numerical Analysis, Computer Science - Machine Learning, Mathematics - Dynamical Systems
Abstract

In this paper we consider utilizing a residual neural network (ResNet) to solve ordinary differential equations. Stochastic gradient descent method is applied to obtain the optimal parameter set of weights and biases of the network. We apply forward Euler, Runge-Kutta2 and Runge-Kutta4 finite difference methods to generate three sets of targets training the ResNet and carry out the target study. The well trained ResNet behaves just as its counterpart of the corresponding one-step finite difference method. In particular, we carry out (1) the architecture study in terms of number of hidden layers and neurons per layer to find the optimal ResNet structure; (2) the target study to verify the ResNet solver behaves as accurate as its finite difference method counterpart; (3) solution trajectory simulation. Even the ResNet solver looks like and is implemented in a way similar to forward Euler scheme, its accuracy can be as high as any one step method. A sequence of numerical examples are presented to demonstrate the performance of the ResNet solver.

Published
2021

12. Reliability and Validity of the Chinese Version of the People-Centered Primary Care Measure

Author

Wenxin YAN, Jue LIU

Subjects
primary health services, people-centered, health care quality, access, and evaluation, community health services, scale, reliability, validity, Medicine
Abstract

Background The People-Centered Primary Care Measure (PCPCM) scale has proven to be able to evaluate the quality of primary care measures in a accurate, all-round and rapid manner in foreign studies. And after being translated and revised, its Chinese version has been developed by Hong Kong scholars. However, there is not yet any report on the applicability and metrological performance concerning the Chinese version of the PCPCM (PCPCM-C) in the culture and healthcare settings in Chinese mainland. Objective To evaluate the reliability and validity of the PCPCM-C scale, providing evidence for its feasibility in evaluating primary care measures in Chinese mainland. Methods By use of convenience sampling, patients were consecutively selected from six primary care settings (community health center, community health station, township health center and village clinic) located in Henan Province, Shanghai, and Heilongjiang Province from December 8th to 20th, 2021. They received a survey using the General Information Questionnaire developed by us, and the PCPCM-C. Then the PCPCM-C was revised in accordance with the survey results, and the assessment results by 10 Chinese professionals (public health managers, general practice experts and administrators of primary care settings) invited nationwide. After that, the PCPCM-C was analyzed using item, reliability and validity analyses. Results Altogether, 683 cases who handed in responsive questionnaires were included for final analysis. The item-total correlation coefficients of the scale ranged from 0.843 to 0.923 (P1.000 was extracted, and the cumulative variance explained by which was 78.715%, with the load value of each item of 0.826-0.925. The results of confirmatory factor analysis (CFA) showed that the fitting indicators of the initial model were undesirable. After the establishment of a covariance correlation between error variables e1 and e2, e3 and e9, and e10 and e11 according to the indication, the fitting indicators of the model were modified to be acceptable (modified CMIN: χ2/df=2.983, GFI=0.934, AGFI=0.894, RMSEA=0.081, NFI=0.966, RFI=0.954, IFI=0.977, TLI=0.969, CFI=0.977, standardized regression coefficients ranged from 0.790 to 0.900) . The results of known-group validity analysis showed that the total score of PCPCM-C among patients varied significantly by age, rural or urban hukou, household monthly income per person, self-rated health, and chronic disease prevalence, and region (P

Published
2022
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18. Exosomal miR-27b-3p secreted by visceral adipocytes contributes to endothelial inflammation and atherogenesis

Author

Yan Tang, Li-Jie Yang, Hao Liu, Yan-Jue Song, Qi-Qi Yang, Yang Liu, Shu-Wen Qian, and Qi-Qun Tang

Subjects
CP: Metabolism, Biology (General), QH301-705.5
Abstract

Summary: Obesity, particularly increased visceral fat, positively correlates with various metabolic challenges, including atherosclerosis, but the mechanism is not fully understood. The aim of this study is to determine the role of visceral-fat-derived exosomes (Exo) in endothelial cells and atherosclerosis. We show that obesity changes the miRNA profile of visceral adipose exosomes in mice. Importantly, exosomal miR-27b-3p efficiently enters into the vascular endothelial cells and activates the NF-κB pathway by downregulating PPARα. Mechanistically, miR-27b-3p binds directly to the CDS region of PPARα mRNA, thereby promoting mRNA degradation and suppressing translation. In ApoE-deficient mice, administration of miR-27b-3p mimic increases inflammation and atherogenesis, while overexpression of PPARα protects against atherosclerosis. Thus, obesity-induced exosomal miR-27b-3p promotes endothelial inflammation and facilitates atherogenesis by PPARα suppression. We reveal an exosomal pathway by which obesity aggravates atherosclerosis and proposed therapeutic strategies for atherosclerosis in people with obesity.

Published
2023
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19. Bone morphogenetic protein 4 in perivascular adipose tissue ameliorates hypertension through regulation of angiotensinogen

Author

Wen-Juan Mu, Yan-Jue Song, Li-Jie Yang, Shu-Wen Qian, Qi-Qi Yang, Yang Liu, Qi-Qun Tang, and Yan Tang

Subjects
perivascular adipose tissue, metabolism, hypertension, renin-angiotensin-aldosterone system (RAAS), BMP4, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

BackgroundPerivascular adipose tissue (PVAT), an active endocrine organ, exerts direct effect on vascular tone through paracrine. Activation of PVAT metabolism plays an inhibitory role in atherosclerosis via secreting relaxing factors. The present studies were designed to investigate the role of PVAT metabolism in regulation of hypertension.Materials and methodsApolipoprotein E (ApoE) knockout mice with BMP4 knockout in adipose tissue or brown adipose tissue (aP2-DKO or UCP1-DKO, respectively) were used for exploring the role of impaired PVAT metabolism in hypertension. Vascular function was assessed using wire myography. The potential regulatory factor of vascular function was explored using qPCR and ELISA and further confirmed in perivascular fat cell line.ResultsKnockout of BMP4 either in adipose tissue or specifically in BAT aggravates high-fat diet (HFD, 40% fat)-induced hypertension and endothelial dysfunction in ApoE–/– mice. In the meanwhile, deficiency of BMP4 also aggravates Ang II (angiotensin II) -induced hypertension and vascular remodeling in ApoE–/– mice. Moreover, deficiency of BMP4 inhibits NO release and induces ROS production. In vitro system, aortic rings pretreated with PVAT extracts from BMP4-DKO mice showed increased vasoconstriction and reduced endothelial-dependent relaxation compared with the controls. We further demonstrated that PVAT of BMP4-DKO mice expressed higher level of angiotensinogen (AGT) and Ang II compared with the controls.ConclusionImpaired PVAT metabolism aggravates hypertension, and this effect is dependent on the activation of local renin-angiotensin-aldosterone system (RAAS). The results of this study first demonstrate the regulatory role of PVAT metabolism in hypertension.

Published
2022
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21. Third order Maximum-Principle-Satisfying Direct discontinuous Galerkin methods for time dependent convection diffusion equations on unstructured triangle mesh

Author

Chen, Zheng, Huang, Hongying, and Yan, Jue

Subjects
Mathematics - Numerical Analysis
Abstract

We develop 3rd order maximum-principle-satisfying direct discontinuous Galerkin methods [8, 9, 19, 21] for convection diffusion equations on unstructured triangular mesh. We carefully calculate the normal derivative numerical flux across element edges and prove that, with proper choice of parameter pair $(\beta_0,\beta_1)$ in the numerical flux, the quadratic polynomial solution satisfies strict maximum principle. The polynomial solution is bounded within the given range and third order accuracy is maintained. There is no geometric restriction on the meshes and obtuse triangles are allowed in the partition. A sequence of numerical examples are carried out to demonstrate the accuracy and capability of the maximum-principle-satisfying limiter.

Published
2015
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23. Proteotranscriptomic analyses of the midgut and Malpighian tubules after a sublethal concentration of Cry1Ab exposure on Spodoptera litura.

Author

Xu, Ya‐Jing, Zhang, Yu‐Ning, Xue‐Yang, Hao, Shao‐Peng, Wang, Yan‐Jue, Yang, Xiao‐Xue, Shen, Ya‐Qin, Su, Qing, Xiao, Ying Dan, Liu, Jian‐Qiu, Li, Wan‐Shun, He, Qi‐Hua, Chen, Yue, Wang, Li‐Ling, Guo, Hui‐Zhen, Xia, Qing‐You, and Mita, Kazuei

Subjects
SPODOPTERA littoralis, GENE expression, PROTEIN receptors, OXIDATIVE phosphorylation, RNA sequencing, RIBOSOMAL proteins, RIBOSOMES
Abstract

BACKGROUND: Cry1Ab has emerged as a bio‐insecticide to control Spodoptera litura (Lepidoptera: Noctuidae). However, the sublethal effects of Cry1Ab on the physiological changes and molecular level of S. litura have not been well documented. Our aims in this study were to assess the sublethal effect of Cry1Ab on S. litura, including midgut and Malpighian tubules as targets. RESULTS: After sublethal Cry1Ab exposure, distinct histological alterations were mainly observed in the midgut. Furthermore, the results of comparative RNA sequencing and tandem mass tag‐based proteomics showed that, in the midgut, most differential expression genes (DEGs) were up‐regulated and significantly enriched in the serine protease activity pathway, and up‐regulated differential expression proteins (DEPs) were mainly associated with the oxidative phosphorylation pathway, whereas the down‐regulated involved in the ribosome pathways. In the Malpighian tubules, DEGs and DEPs were significantly enriched in the ribosome pathway. We proposed that ribosome may act as a universal target in energy metabolism with other pathways via the results of protein–protein interaction analysis. Further, by verification of the mRNA expression of some Cry protein receptor and detoxification genes after Cry1Ab treatment, it was suggested that the ribosomal proteins (RPs) possibly participate in influencing the Bt‐resistance of S. litura larvae under sublethal Cry1Ab exposure. CONCLUSION: Under sublethal Cry1Ab exposure, the midgut of S. litura was damaged, and the proteotranscriptomic analysis elucidated that Cry1Ab disrupted the energy homeostasis of larvae. Furthermore, we emphasized the potential role of ribosomes in sublethal Cry1Ab exposure. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Published
2024
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34. Ginger-indirect moxibustion plus acupuncture versus acupuncture alone for chronic fatigue syndrome: a randomized controlled trial

Author

MA, Tingting, WU, Jie, YANG, Lijie, FENG, Fen, YANG, Huilin, ZHANG, Jinhua, ZHONG, Yanjin, NING, Qing, HUANG, Lirong, LIN, Youbing, YAN, Jue, CHEN, Guiquan, HOU, Tianshu, WANG, Li, REN, Yuanfang, and TAN, Jing

Subjects
Fatigue Syndrome, Chronic, Treatment Outcome, Moxibustion, Acupuncture Therapy, Humans, Ginger, Research Articles
Abstract

OBJECTIVE: To assess the efficacy and safety of ginger-indirect moxibustion for chronic fatigue syndrome (CFS). METHODS: In this central randomized, controlled trial, 290 CFS participants were recruited and randomly allocated to group A (ginger-indirect moxibustion plus acupuncture) or group B (acupuncture alone). The study consisted of a treatment period of 8 weeks with a total of 24 treatments (3 sessions per week, every other day), and a follow-up period of 12 weeks. The outcome was measured by Fatigue Severity Scale (FSS), Psychological Health Report (SPHERE), the Self-rating depression scale (SDS) and the Hamilton anxiety scale (HAMA) at baseline, 2, 4, 6, 8, 12 and 20 weeks. RESULTS: With the treatment undergoing, the changes of FSS, SPHERE, SDS and HAMA scores in both groups increased gradually, and the effect maintained at the 12th week. Between groups, significantly higher score changes were seen in group A in FSS after 4 weeks treatment (11.94 vs 9.12, 95%CI: 0.94, 4.7) and in SPHERE after 2 weeks treatment (3.7 vs 2.27, 95%CI: 0.56, 2.31). But for SDS and HAMA, the improvement did not differ significantly between groups. No severe adverse events were reported. CONCLUSION: Ginger-indirect moxibustion is a safe and effective intervention to relieve fatigue and accompanying physical symptoms of CFS.

Published
2021

37. The role of 99mTc-MIBI SPECT-CT in reoperation therapy of persistent hyperparathyroidism patients

Author

Yin Lijie, Guo Dandan, Liu Jie, and Yan Jue

Subjects
Secondary hyperparathyroidism, Parathyroidectomy with auto transplantation, 99mTc-MIBI, SPECT-CT, Persistent hyperparathyroidism, Medicine
Abstract

To compare the role of 99mTc-MIBI SPECT-CT image and US in reoperation of persistent secondary hyperparathyroidism patients. A total of 8 persistent secondary hyperparathyroidism patients underwent parathyroidectomy. The sensitivity and accuracy of US and 99mTc-MIBI images before operation were determined. 9 of 14 surgical resection tissues from 8 persistent secondary hyperparathyroidism patients were confirmed to parathyroid hyperplasia. The results showed that the sensitivities were 77.8% and 100%, respectively, for US and 99mTc-MIBI SPECT-CT images. And the accuracies of US and 99mTc-MIBI dual time planar image and SPECT-CT were 50%, 78.6%, respectively. There was significantly difference between two procedures (P=0.021). The superior and inferior localization of glands were both detected by the ultrasound and scintigraphy. Two ectopic parathyroidism nodules were found by 99mTc- MIBI SPECT-CT imaging, while US provided no consistent findings. There was no significantly difference between two procedures (P=0.3). Although two cases of them were not confirmed by pathology, the iPTH of them (800 and 1429 respectively) were much higher than other four cases (

Published
2015
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41. Superconvergence of Direct Discontinuous Galerkin Methods: Eigen-structure Analysis Based on Fourier Approach

Author

Liu, Xuechun, Wang, Haijin, Yan, Jue, and Zhong, Xinghui

Abstract

This paper investigates superconvergence properties of the direct discontinuous Galerkin (DDG) method with interface corrections and the symmetric DDG method for diffusion equations. We apply the Fourier analysis technique to symbolically compute eigenvalues and eigenvectors of the amplification matrices for both DDG methods with different coefficient settings in the numerical fluxes. Based on the eigen-structure analysis, we carry out error estimates of the DDG solutions, which can be decomposed into three parts: (i) dissipation errors of the physically relevant eigenvalue, which grow linearly with the time and are of order 2kfor Pk(k=2,3)approximations; (ii) projection error from a special projection of the exact solution, which is decreasing over the time and is related to the eigenvector corresponding to the physically relevant eigenvalue; (iii) dissipative errors of non-physically relevant eigenvalues, which decay exponentially with respect to the spatial mesh size Δx. We observe that the errors are sensitive to the choice of the numerical flux coefficient for even degree P2approximations, but are not for odd degree P3approximations. Numerical experiments are provided to verify the theoretical results.

Published
2023
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50. Research on the Variety Law of Time-Dependent Reliability Model of Picking Link Rod in Sewing Machine

Author

Yan Jue Gong, Yuan Zhang, Hui Yu Xiang, Fu Zhao, Hong Bing Xin, and Chun Ling Meng

Subjects
Engineering, Sewing machine, business.industry, Component (UML), Process (computing), General Medicine, business, Link (knot theory), Standard deviation, Simulation, Reliability model, Reliability (statistics), Reliability engineering
Abstract

The reliability of mechanical component is a time-varied process because the parameters such as operation condition, load, strength, are varied with time or the loading numbers. This paper builds the time-dependent reliability model when life is measured by the loading numbers. The variety-law of component’s reliability with the lifetime is derived from the built model and simulation of picking link rod used in sewing machine. It is shown that the time-dependent reliability model is effective and the reliability of component decreases obviously with the time and the increasing load standard deviation.

Published
2015

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